UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d)

of the Securities Exchange Act of 1934

Date of Report (Date of earliest event reported): February 11, 2019

UNITED AIRLINES, INC.

(Exact name of registrant as specified in its charter)

(872) 825-4000

Registrant’s telephone number, including area code

(Former name or former address, if changed since last report.)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter).

Emerging growth company  ☐

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act.   ☐

On February 11, 2019, United Airlines, Inc. (the “Company”),Wilmington Trust, National Association, as subordination agent and pass through trustee (the “Trustee”) under certain pass through trusts newly formed by the Company, U.S. Bank National Association, as escrow agent under the Escrow Agreements (as defined below), and Wilmington Trust, National Association, as paying agent (the “Paying Agent”) under the Escrow Agreements, entered into the Note Purchase Agreement, dated as of February 11, 2019 (the “Note Purchase Agreement”). The Note Purchase Agreement provides for the future issuance by the Company of equipment notes (the “Equipment Notes”) in the aggregate principal amount of $1,013,070,000 to finance 15 new Boeing aircraft and 10 new Embraer aircraft scheduled for delivery between November 2018 and July 2019 (collectively, such new aircraft to be financed, the “Aircraft”). Pursuant to the Note Purchase Agreement, upon the financing of each Aircraft, the Trustee will purchase Equipment Notes issued under a trust indenture and mortgage (each, an “Indenture” and, collectively, the “Indentures”) with respect to such Aircraft to be entered into by the Company and Wilmington Trust, National Association, as mortgagee.

Each Indenture contemplates the issuance of Equipment Notes in two series: Series AA, bearing interest at the rate of 4.15% per annum, and Series A, bearing interest at the rate of 4.55% per annum, in aggregate principal amounts (once all the Equipment Notes have been issued) equal to $716,625,000 and $296,445,000, respectively. The Equipment Notes will be purchased by the Trustee, using the proceeds from the sale of Pass Through Certificates, Series 2019-1AA, and Pass Through Certificates, Series 2019-1A (collectively, the “Certificates” and each series of the Certificates, a “Class”), issued by two pass through trusts newly-formed by the Company to facilitate the financing of the Aircraft.

Pending the purchase of the Equipment Notes, the proceeds from the sale of the Certificates of each Class were placed in escrow by the Trustee pursuant to an Escrow and Paying Agent Agreement, dated as of February 11, 2019, among U.S. Bank National Association, as escrow agent, Citigroup Global Markets Inc. and Credit Suisse Securities (USA) LLC, for themselves and on behalf of the several underwriters of the Certificates, and Wilmington Trust, National Association, as Trustee and Paying Agent, corresponding to such Class (each, an “Escrow Agreement” and, collectively, the “Escrow Agreements”). The escrowed funds were deposited with Sumitomo Mitsui Banking Corporation, acting through its New York Branch, under a separate deposit agreement for each Class of Certificates, each dated as of February 11, 2019, between U.S. Bank National Association, as escrow agent, and Sumitomo Mitsui Banking Corporation, acting through its New York Branch, as depositary.

The interest on the Equipment Notes and the escrowed funds is payable semi-annually on each February 25 and August 25, beginning on August 25, 2019. The principal payments on the Equipment Notes are scheduled on February 25 and August 25 of each year, beginning on February 25, 2020. The final payments will be due on August 25, 2031. Maturity of the Equipment Notes may be accelerated upon the occurrence of certain events of default, including failure by the Company (in some cases after notice or the expiration of a grace period, or both) to make payments under the applicable Indenture when due or to comply with certain covenants, as well as certain bankruptcy events involving the Company. The Equipment Notes issued with

respect to each Aircraft will be secured by a lien on such Aircraft and will also be cross-collateralized by the other Aircraft financed pursuant to the Note Purchase Agreement.

The Certificates were registered for offer and sale pursuant to the Securities Act of 1933, as amended (the “Securities Act”), under the Company’s automatic shelf registration statement on Form S-3 (File No. 333-221865) (the “Registration Statement”).

The foregoing description of these agreements and instruments is qualified in its entirety by reference to these agreements and instruments, copies of which are filed herewith as exhibits and are incorporated by reference herein. For a more detailed description of the agreements and instruments entered into by the Company with respect to the Certificates, see the disclosure under the captions “Description of the Certificates”, “Description of the Deposit Agreements”, “Description of the Escrow Agreements”, “Description of the Liquidity Facilities”, “Description of the Intercreditor Agreement”, “Description of the Equipment Notes” and “Underwriting” contained in the Company’s final Prospectus Supplement, dated January 28, 2019 (the “Prospectus Supplement”), to the Prospectus, dated December 1, 2017, filed with the Securities and Exchange Commission on January 29, 2019 pursuant to Rule 424(b) under the Securities Act, which disclosure is hereby incorporated herein by reference.

The information set forth in Item 1.01 above is hereby incorporated by reference in this Item 2.03.

(d)    Exhibits. The documents listed as exhibits below are filed as exhibits with reference to the Registration Statement. The Registration Statement and the final Prospectus Supplement, dated January 28, 2019, to the Prospectus, dated December 1, 2017, relate to the offering of the Certificates.

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

Exhibit 1.1

EXECUTION VERSION

UNITED AIRLINES, INC.

$716,625,000

United Airlines Pass Through Certificates, Series 2019-1AA-O

$296,445,000

United Airlines Pass Through Certificates, Series 2019-1A-O

UNDERWRITING AGREEMENT

January 28, 2019

CITIGROUP GLOBAL MARKETS INC.

CREDIT SUISSE SECURITIES (USA) LLC

As representatives of the several underwriters

    named in Schedule II hereto

c/o Citigroup Global Markets Inc.

388 Greenwich Street

New York, New York 10013

c/o Credit Suisse Securities (USA) LLC

Eleven Madison Avenue

New York, New York 10010

Ladies and Gentlemen:

United Airlines, Inc., a Delaware corporation (the “Company”), proposes that Wilmington Trust, National Association, as trustee under each of the Original Trusts (as defined below) (each, a “Trustee”), issue and sell to the underwriters named in Schedule II hereto United Airlines Pass Through Certificates, Series 2019-1AA-O (the “Class AA Certificates”) and United Airlines Pass Through Certificates, Series 2019-1A-O (the “Class A Certificates” and, together with the Class AA Certificates, the “Certificates”), in the aggregate face amounts and with the interest rates and final expected distribution dates set forth on Schedule I hereto on the terms and conditions stated herein.

The Certificates will be issued pursuant to a Pass Through Trust Agreement, dated as of October 3, 2012 (the “Basic Agreement”), between the Company and the Trustee, as supplemented with respect to the issuance of each class of Certificates by a separate Pass Through Trust Supplement to be dated as of the Closing Date (as defined below) (individually, an “Original Trust Supplement”), between the Company and the Trustee (the Basic Agreement

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as supplemented by each such Original Trust Supplement being referred to herein individually as an “Original Pass Through Trust Agreement”). The Original Trust Supplements are related to the creation and administration of United Airlines Pass Through Trust 2019-1AA-O (the “Class AA Trust”) and United Airlines Pass Through Trust 2019-1A-O (the “Class A Trust” and, together with the Class AA Trust, the “Original Trusts”). As used herein, unless the context otherwise requires, the term “Underwriters” shall mean the firms named as Underwriters in Schedule II, and the term “Representatives” shall mean, collectively, Citigroup Global Markets Inc. (“Citigroup”) and Credit Suisse Securities (USA) LLC (“Credit Suisse”), on behalf of the Underwriters.

The cash proceeds of the offering of Certificates by each Original Trust will be paid to U.S. Bank National Association, as escrow agent (each, an “Escrow Agent”), under an Escrow and Paying Agent Agreement among the Escrow Agent, the Representatives of the Underwriters, the Trustee of such Original Trust and Wilmington Trust, National Association, as paying agent (the “Paying Agent”), for the benefit of the holders of Certificates issued by such Original Trust (each, an “Escrow Agreement”). The Escrow Agent will deposit such cash proceeds (each, a “Deposit”) with Sumitomo Mitsui Banking Corporation, acting through its New York Branch (the “Depositary”), in accordance with a Deposit Agreement relating to such Original Trust (each, a “Deposit Agreement”), and, subject to the fulfillment of certain conditions, will withdraw Deposits upon request to allow the Trustee to purchase Equipment Notes (as defined in the Note Purchase Agreement (as defined below)) from time to time pursuant to a Note Purchase Agreement to be dated as of the Closing Date (the “Note Purchase Agreement”), among the Company, Wilmington Trust, National Association, as Trustee of each of the Original Trusts, as Subordination Agent (as hereinafter defined) and as Paying Agent, and the Escrow Agent. Each Escrow Agent will issue receipts to be attached to each related Certificate (“Escrow Receipts”) representing each holder’s interest in amounts deposited with the Depositary by such Escrow Agent with respect to the related class of Certificates and will pay to such holders through the related Paying Agent interest accrued on the Deposits and received by such Paying Agent pursuant to the related Deposit Agreement at a rate per annum equal to the interest rate applicable to the corresponding Certificates.

On the earlier of (i) the first Business Day after November 30, 2019 or, if later, the fifth Business Day after the Delivery Period Termination Date (as defined in the applicable Original Trust Supplement) and (ii) the fifth Business Day following the occurrence of a Triggering Event (as defined in the Intercreditor Agreement) (such Business Day, the “Trust Transfer Date”), each of the Original Trusts will transfer and assign all of its assets and rights to a newly-created successor trust with substantially identical terms except as described in the Prospectus (as hereinafter defined) (each, a “Successor Trust” and, together with the Original Trusts, the “Trusts”) governed by the Basic Agreement, as supplemented with respect to each class of Certificates by a separate Pass Through Trust Supplement (individually, a “Successor Trust Supplement”), between the Company and the Trustee (the Basic Agreement, as supplemented by each such Successor Trust Supplement, being referred to herein individually as a “Successor Pass Through Trust Agreement” and, together with the Original Pass Through Trust Agreements, the “Designated Agreements”). Each Certificate outstanding on the Trust Transfer Date will represent the same interest in the Successor Trust as the Certificate represented in the

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Original Trust. Wilmington Trust, National Association initially will also act as trustee of the Successor Trusts.

Certain amounts of interest payable on the Certificates issued by the Class AA Trust and the Class A Trust will be entitled, in each case, to the benefits of a separate liquidity facility. National Australia Bank Limited, acting through its New York Branch (the “Liquidity Provider”), will enter into separate revolving credit agreements with respect to the Class AA Trust and the Class A Trust (collectively, the “Liquidity Facilities”) to be dated as of the Closing Date for the benefit of the holders of the Certificates issued by such Trusts. The Liquidity Provider and the holders of the Certificates will be entitled to the benefits of an Intercreditor Agreement to be dated as of the Closing Date (the “Intercreditor Agreement”) among the Trustees, Wilmington Trust, National Association, as subordination agent and trustee thereunder (the “Subordination Agent”), and the Liquidity Provider.

The Company has filed with the Securities and Exchange Commission (the “Commission”) an automatic shelf registration statement on Form S-3 (File No. 333-221865) relating to securities, including pass through certificates (the “Shelf Securities”), to be issued from time to time by the Company. The registration statement (including the respective exhibits thereto and the respective documents filed by the Company with the Commission pursuant to the Securities Exchange Act of 1934, as amended, and the rules and regulations of the Commission thereunder (collectively, the “Exchange Act”), that are incorporated by reference therein), as amended to and including the date of this Underwriting Agreement (the “Agreement”), including the information (if any) deemed to be part of the registration statement pursuant to Rule 430B under the Securities Act of 1933, as amended, and the rules and regulations of the Commission thereunder (collectively, the “Securities Act”) (and the Underwriters confirm that the first contract of sale of the Certificates by the Underwriters was made on the date of this Agreement), is hereinafter referred to as the “Registration Statement”, and the related prospectus covering the Shelf Securities dated December 1, 2017 filed as part of the Registration Statement, in the form in which it has most recently been filed with the Commission on or prior to the date of this Agreement, is hereinafter referred to as the “Basic Prospectus”. The Basic Prospectus, as supplemented by the final prospectus supplement specifically relating to the Certificates in the form as first filed with the Commission pursuant to Rule 424(b) under the Securities Act in accordance with Section 4(d) hereof is hereinafter referred to as the “Prospectus”, and the term “preliminary prospectus” means the preliminary form of the Prospectus filed with the Commission pursuant to Rule 424 under the Securities Act. For purposes of this Agreement, (i) “free writing prospectus” has the meaning set forth in Rule 405 under the Securities Act and (ii) “Time of Sale Prospectus” means the preliminary prospectus together with the free writing prospectus identified in Item 1 of Schedule IV hereto. As used herein, the terms “Registration Statement”, “Basic Prospectus”, “preliminary prospectus”, “Time of Sale Prospectus” and “Prospectus” shall include the documents, if any, incorporated by reference therein. The terms “supplement”, “amendment” and “amend” as used herein with respect to the Registration Statement, the Basic Prospectus, the Time of Sale Prospectus, the Prospectus, any preliminary prospectus or any free writing prospectus shall include all documents subsequently filed by the Company with the Commission pursuant to the Exchange Act and incorporated by reference therein.

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Capitalized terms used but not defined in this Agreement shall have the meanings specified therefor in the Original Pass Through Trust Agreements, the Note Purchase Agreement or the Intercreditor Agreement; provided that, as used in this Agreement, the term “Operative Agreements” shall mean the Deposit Agreements, the Escrow Agreements, the Intercreditor Agreement, the Liquidity Facilities, the Designated Agreements, the Assignment and Assumption Agreements and the Financing Agreements (as defined in the Note Purchase Agreement).

1.    Representations and Warranties. (a) The Company represents and warrants to, and agrees with each Underwriter that:

(i)    The Company meets the requirements for use of Form S-3 under the Securities Act; the Registration Statement has become effective; and, on the original effective date of the Registration Statement, the Registration Statement complied in all material respects with the requirements of the Securities Act; no stop order suspending the effectiveness of the Registration Statement is in effect, and no proceedings for such purpose are pending before or, to the knowledge of the Company, threatened by the Commission. The Registration Statement is an “automatic shelf registration statement” (as defined in Rule 405 under the Securities Act) and the Company is a “well-known seasoned issuer” (as defined in Rule 405 under the Securities Act) eligible to use the Registration Statement as an automatic shelf registration statement, and the Company has not received notice that the Commission objects to the use of the Registration Statement as an automatic shelf registration statement. The Registration Statement does not, as of the date hereof, include any untrue statement of a material fact or omit to state any material fact required to be stated therein or necessary to make the statements therein not misleading. As of its date and on the Closing Date, the Prospectus, as amended and supplemented, if the Company shall have made any amendment or supplement thereto, does not and will not include an untrue statement of a material fact and does not and will not omit to state a material fact necessary in order to make the statements therein, in the light of the circumstances under which they were made, not misleading. The Registration Statement, as of the date hereof, complies and the Prospectus complies, and as amended or supplemented, if applicable, will comply in all material respects with the Securities Act and the applicable rules and regulations of the Commission thereunder. The Time of Sale Prospectus did not, as of 4:30 P.M., Eastern Time, on the date of this Agreement (the “Applicable Time”), and the Time of Sale Prospectus, as then amended or supplemented by the Company, if applicable, will not as of the Closing Date, contain any untrue statement of a material fact or omit to state a material fact necessary to make the statements therein, in the light of the circumstances under which they were made, not misleading. Any information included in any “issuer free writing prospectus” (as defined in Rule 433(h) under the Securities Act) used in connection with the offering of the Certificates does not conflict with the information contained in the Registration Statement, including any prospectus or prospectus supplement that is part of the Registration Statement (including pursuant to Rule 430B under the Securities Act) and not superseded or modified and, when taken together with the Time of Sale Prospectus, as amended and supplemented, each such “issuer free writing prospectus”, as amended and supplemented, did not as of the Applicable Time, and will not as of the Closing Date,

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contain any untrue statement of a material fact or omit to state a material fact necessary to make the statements therein, in the light of the circumstances under which they were made, not misleading. The preceding sentences do not apply to statements in or omissions from the Registration Statement, the Time of Sale Prospectus or the Prospectus based upon (A) written information furnished to the Company by any Underwriter through the Representatives expressly for use therein, (B) statements or omissions in that part of each Registration Statement which shall constitute the Statement of Eligibility of the Trustee under the Trust Indenture Act of 1939, as amended (the “Trust Indenture Act”), on Form T-1, or (C) the Depositary Information (as hereinafter defined).

(ii)    The documents incorporated by reference in the Time of Sale Prospectus or the Prospectus pursuant to Item 12 of Form S-3 under the Securities Act, at the time they were filed with the Commission or hereafter, during the period mentioned in Section 4(a) hereof, are filed with the Commission, complied or will comply, as the case may be, in all material respects with the requirements of the Exchange Act.

(iii)    The Company is not an “ineligible issuer” in connection with the offering of the Certificates pursuant to Rules 164, 405 and 433 under the Securities Act. Any free writing prospectus that the Company is required to file pursuant to Rule 433(d) under the Securities Act has been, or will be, filed with the Commission in accordance with the requirements of the Securities Act and the applicable rules and regulations of the Commission thereunder. Each free writing prospectus that the Company has filed in connection with the offering of the Certificates, or is required to file in connection with the offering of the Certificates, pursuant to Rule 433(d) under the Securities Act complies or will comply in all material respects with the requirements of the Securities Act and the applicable rules and regulations of the Commission thereunder. Except for the free writing prospectuses, if any, identified in Schedule IV hereto, the Company has not prepared, used or referred to, any free writing prospectus in connection with the offering of the Certificates.

(iv)    The Company has been duly incorporated and is an existing corporation in good standing under the laws of the State of Delaware, with corporate power and authority to own, lease and operate its property and to conduct its business as described in the Time of Sale Prospectus; and the Company is duly qualified to do business as a foreign corporation in good standing in all other jurisdictions in which its ownership or lease of property or the conduct of its business requires such qualification, except where the failure to be so qualified would not have a material adverse effect on the condition (financial or otherwise), business, properties or results of operations of the Company and its consolidated subsidiaries taken as a whole (a “United Material Adverse Effect”).

(v)    Air Micronesia, LLC (the “Subsidiary”) has been duly formed and is a limited liability company in good standing under the laws of the jurisdiction of its formation, with limited liability company power and authority to own, lease and operate its properties and to conduct its business as described in the Time of Sale Prospectus; and the Subsidiary is duly qualified to do business as a foreign corporation in good standing in all other jurisdictions in which its ownership or lease of property or the conduct of its business requires such qualification, except where the failure to be so qualified would not

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have a United Material Adverse Effect; all of the membership interests of the Subsidiary have been duly authorized and validly issued and are fully paid and nonassessable; and, except as described in the Time of Sale Prospectus, the Subsidiary’s membership interests are owned by the Company, directly or through subsidiaries, free from liens, encumbrances and defects.

(vi)    Except as described in the Time of Sale Prospectus, the Company is not in default in the performance or observance of any obligation, agreement, covenant or condition contained in any contract, indenture, mortgage, loan agreement, note, lease or other instrument to which it is a party or by which it may be bound or to which any of its properties may be subject, except for such defaults that would not have a United Material Adverse Effect. The execution, delivery and performance of this Agreement and the Operative Agreements to which the Company is or will be a party and the consummation by the Company of the transactions contemplated herein and therein have been duly authorized by all necessary corporate action of the Company and will not result in any breach of any of the terms, conditions or provisions of, or constitute a default under, or result in the creation or imposition of any lien, charge or encumbrance (other than any lien, charge or encumbrance created under any Operative Agreement) upon any property or assets of the Company pursuant to any indenture, loan agreement, contract, mortgage, note, lease or other instrument to which the Company is a party or by which the Company may be bound or to which any of the property or assets of the Company is subject, which breach, default, lien, charge or encumbrance, individually or in the aggregate, would have a United Material Adverse Effect, nor will any such execution, delivery or performance result in any violation of the provisions of the charter or by-laws of the Company or any statute, any rule, regulation or order of any governmental agency or body or any court having jurisdiction over the Company.

(vii)    No consent, approval, authorization or order of, or filing with, any governmental agency or body or any court is required for the valid authorization, execution and delivery by the Company of this Agreement and the Operative Agreements to which it is or will be a party and for the consummation of the transactions contemplated herein and therein, except (x) such as may be required under the Securities Act, the Trust Indenture Act, the securities or “blue sky” or similar laws of the various states and of foreign jurisdictions or rules and regulations of the Financial Industry Regulatory Authority, Inc. (“FINRA”), and (y) filings or recordings with the Federal Aviation Administration (the “FAA”) and under the Uniform Commercial Code (the “UCC”) or other laws in effect in any applicable jurisdiction governing the perfection of security interests, which filings or recordings referred to in this clause (y), with respect to any particular set of Financing Agreements, shall have been made, or duly presented for filing or recordation, or shall be in the process of being duly filed or filed for recordation, on or prior to the applicable Funding Date (as defined in the Note Purchase Agreement) for each of the nine Boeing 737 MAX 9 aircraft, six Boeing 787-10 aircraft and ten Embraer ERJ 175 LL aircraft (collectively, the “Aircraft”) related to such Financing Agreements.

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(viii)    This Agreement has been duly authorized, executed and delivered by the Company and the Operative Agreements to which the Company will be a party have been duly authorized and will be duly executed and delivered by the Company on or prior to the Closing Date or the applicable Funding Date, as the case may be.

(ix)    The Operative Agreements to which the Company is or will be a party, when duly executed and delivered by the Company, assuming that such Operative Agreements have been duly authorized, executed and delivered by, and constitute legal, valid and binding obligations of, each other party thereto, will constitute valid and binding obligations of the Company enforceable in accordance with their terms, except (w) as enforcement thereof may be limited by bankruptcy, insolvency (including, without limitation, all laws relating to fraudulent transfers), reorganization, moratorium or other similar laws now or hereafter in effect relating to creditors’ rights generally, (x) as enforcement thereof is subject to general principles of equity (regardless of whether enforcement is considered in a proceeding in equity or at law), (y) that the enforceability of the Indentures may also be limited by applicable laws which may affect the remedies provided therein but which do not affect the validity of the Indentures or make such remedies inadequate for the practical realization of the benefits intended to be provided thereby and (z) with respect to indemnification and contribution provisions, as enforcement thereof may be limited by applicable law, and subject, in the case of the Successor Pass Through Trust Agreements, to the delayed effectiveness thereof as set forth therein. The Basic Agreement has been duly qualified under the Trust Indenture Act. The Certificates, the Escrow Receipts and the Designated Agreements to which the Company is, or is to be, a party, will, upon execution and delivery thereof, conform in all material respects to the descriptions thereof in the Time of Sale Prospectus.

(x)    The consolidated financial statements of the Company incorporated by reference in the Time of Sale Prospectus, together with the related notes thereto, present fairly in all material respects the financial position of the Company and its consolidated subsidiaries at the dates indicated and the consolidated results of operations and cash flows of the Company and its consolidated subsidiaries for the periods specified. Such financial statements have been prepared in conformity with generally accepted accounting principles applied on a consistent basis throughout the periods involved, except as otherwise stated therein and except that unaudited financial statements do not have all required footnotes. The financial statement schedules, if any, incorporated by reference in the Time of Sale Prospectus present the information required to be stated therein.

(xi)    The Company is a “citizen of the United States” within the meaning of Section 40102(a)(15) of Title 49 of the United States Code, as amended, and holds an air carrier operating certificate issued pursuant to Chapter 447 of Title 49 of the United States Code, as amended, for aircraft capable of carrying 10 or more individuals or 6,000 pounds or more of cargo. All of the outstanding shares of capital stock of the Company have been duly authorized and validly issued and are fully paid and non-assessable.

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(xii)    On or prior to the Closing Date, the issuance of the Certificates will be duly authorized by the Trustee. When duly executed, authenticated, issued and delivered in the manner provided for in the Original Pass Through Trust Agreements and sold and paid for as provided in this Agreement, the Certificates will be legally and validly issued and will be entitled to the benefits of the relevant Original Pass Through Trust Agreement; based on applicable law as in effect on the date hereof, upon the execution and delivery of the Assignment and Assumption Agreements in accordance with the Original Pass Through Trust Agreements, the Certificates will be legally and validly outstanding under the related Successor Pass Through Trust Agreements; and when executed, authenticated, issued and delivered in the manner provided for in the Escrow Agreements, the Escrow Receipts will be legally and validly issued and will be entitled to the benefits of the related Escrow Agreements.

(xiii)    Except as disclosed in the Time of Sale Prospectus, the Company and the Subsidiary have good and marketable title to all real properties and all other properties and assets owned by them, in each case free from liens, encumbrances and defects except where the failure to have such title would not have a United Material Adverse Effect; and except as disclosed in the Time of Sale Prospectus, the Company and the Subsidiary hold any leased real or personal property under valid and enforceable leases with no exceptions that would have a United Material Adverse Effect.

(xiv)    Except as disclosed in the Time of Sale Prospectus, there is no action, suit or proceeding before or by any governmental agency or body or court, domestic or foreign, now pending or, to the knowledge of the Company, threatened against the Company or any of its subsidiaries or any of their respective properties that individually (or in the aggregate in the case of any class of related lawsuits), could reasonably be expected to result in a United Material Adverse Effect or that could reasonably be expected to materially and adversely affect the consummation of the transactions contemplated by this Agreement or the Operative Agreements.

(xv)    Except as disclosed in the Time of Sale Prospectus, no labor dispute with the employees of the Company or any subsidiary exists or, to the knowledge of the Company, is imminent that could reasonably be expected to have a United Material Adverse Effect.

(xvi)    Each of the Company and the Subsidiary has all necessary consents, authorizations, approvals, orders, certificates and permits of and from, and has made all declarations and filings with, all federal, state, local and other governmental authorities, all self-regulatory organizations and all courts and other tribunals, to own, lease, license and use its properties and assets and to conduct its business in the manner described in the Prospectus, except to the extent that the failure to so obtain, declare or file would not have a United Material Adverse Effect.

(xvii)    Except as disclosed in the Time of Sale Prospectus, (x) neither the Company nor the Subsidiary is in violation of any statute, rule, regulation, decision or order of any governmental agency or body or any court, domestic or foreign, relating to

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the use, disposal or release of hazardous or toxic substances (collectively, “environmental laws”), owns or operates any real property contaminated with any substance that is subject to any environmental laws, or is subject to any claim relating to any environmental laws, which violation, contamination, liability or claim individually or in the aggregate is reasonably expected to have a United Material Adverse Effect, and (y) the Company is not aware of any pending investigation which might lead to such a claim that is reasonably expected to have a United Material Adverse Effect.

(xviii)    Ernst & Young LLP, who examined and issued an auditors’ report with respect to the consolidated financial statements of the Company and the financial statement schedules of the Company, if any, included or incorporated by reference in the Registration Statement, is an independent registered public accounting firm with respect to the Company and its subsidiaries within the meaning of the Securities Act.

(xix)    The preliminary prospectus filed pursuant to Rule 424 under the Securities Act and included in the Time of Sale Prospectus, complied when so filed in all material respects with the Securities Act and the applicable rules and regulations of the Commission thereunder.

(xx)    Neither the Company nor any of the Original Trusts is, nor (based on applicable law as in effect on the date hereof) will any of the Successor Trusts be, as of the execution and delivery of the Assignment and Assumption Agreements in accordance with the Original Pass Through Trust Agreements, an “investment company”, or an entity “controlled” by an “investment company”, within the meaning of the Investment Company Act of 1940, as amended (the “Investment Company Act”), in each case required to register under the Investment Company Act; and after giving effect to the offering and sale of the Certificates and the application of the proceeds thereof as described in the Prospectus, neither the Original Trusts will be, nor (based on applicable law as in effect on the date hereof) will any of the Successor Trusts be, as of the execution and delivery of the Assignment and Assumption Agreements in accordance with the Original Pass Through Trust Agreements, nor will the escrow arrangements contemplated by the Escrow Agreements result in the creation of, an “investment company”, or an entity “controlled” by an “investment company”, as defined in the Investment Company Act, in each case required to register under the Investment Company Act and in making the foregoing determinations as to the Trusts the Company and each of the Trusts is relying upon an analysis that the Trusts will not be deemed to be an “investment company” under Rule 3a-7 promulgated by the Commission, under the Investment Company Act, although other exemptions or exclusions may be available to the Trusts. Each of the Trusts is not a “covered fund” as defined in the final regulations issued December 10, 2013, implementing the “Volcker Rule” (Section 619 of the Dodd-Frank Wall Street Reform and Consumer Protection Act).

(xxi)    This Agreement and the other Operative Agreements to which the Company is or will be a party will, upon execution and delivery thereof, conform in all material respects to the descriptions thereof contained in the Time of Sale Prospectus

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(other than, in the case of the Financing Agreements to be executed and delivered after the Closing Date, as described in the Time of Sale Prospectus).

(xxii)    None of Aircraft Information Services, Inc., BK Associates, Inc. or Morten Beyer and Agnew, Inc. (each, an “Appraiser” and, collectively, the “Appraisers”) is an affiliate of the Company or, to the knowledge of the Company, has a substantial interest, direct or indirect, in the Company. To the knowledge of the Company, none of the officers and directors of any of such Appraisers is connected with the Company or any of its affiliates as an officer, employee, promoter, underwriter, trustee, partner, director or person performing similar functions.

(xxiii)    The Company (A) makes and keeps books, records and accounts, which, in reasonable detail, accurately and fairly reflect the transactions and dispositions of the material assets of the Company and its consolidated subsidiaries and (B) maintains a system of internal accounting controls sufficient to provide reasonable assurances that (1) transactions are executed in accordance with management’s general or specific authorization; (2) transactions are recorded as necessary: (x) to permit preparation of financial statements in conformity with generally accepted accounting principles or any other criteria applicable to such statements and (y) to maintain accountability for assets; (3) access to material assets is permitted only in accordance with management’s general or specific authorization; and (4) the recorded accountability for material assets is compared with the existing material assets at reasonable intervals and appropriate action is taken with respect to any differences.

(xxiv)    The interactive data in eXtensible Business Reporting Language included or incorporated by reference in the Registration Statement fairly presents the information called for in all material respects and has been prepared in accordance with the Commission’s rules and guidelines applicable thereto.

(xxv)    Except as set forth in the Time of Sale Prospectus, (A) the Company maintains required “disclosure controls and procedures” (as defined in Rule 15d-15(e) under the Exchange Act); and (B) the Company’s “disclosure controls and procedures” are designed to reasonably ensure that material information (both financial and non-financial) required to be disclosed by the Company in the reports that it files or furnishes under the Exchange Act is communicated to the Company’s management as appropriate to allow timely decisions regarding required disclosure and to make the certifications of the Chief Executive Officer and the Chief Financial Officer of the Company required under the Exchange Act with respect to such reports.

(xxvi)    The Company and its subsidiaries have instituted and maintained policies and procedures designed to promote and achieve compliance with the Foreign Corrupt Practices Act of 1977, as amended, and to the knowledge of the Company, the Company and its subsidiaries have conducted their businesses in compliance with such policies and procedures.

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(xxvii)     The operations of the Company and its subsidiaries are and have been conducted at all times in material compliance with all applicable financial recordkeeping and reporting requirements, including those of the Bank Secrecy Act, as amended by Title III of the Uniting and Strengthening America by Providing Appropriate Tools Required to Intercept and Obstruct Terrorism Act of 2001 (USA PATRIOT Act), the rules and regulations thereunder and any related or similar rules, regulations or guidelines, issued, administered or enforced by any U.S. governmental agency (collectively, the “Anti-Money Laundering Laws”), and no action, suit or proceeding by or before any court or governmental agency, authority or body or any arbitrator involving the Company or any of its subsidiaries with respect to the Anti-Money Laundering Laws is pending or, to the best knowledge of the Company, threatened.

(xxviii)     None of the Company nor any of its subsidiaries (collectively, the “Company Entity”) or, to the knowledge of the Company, any director, executive officer or affiliate of the Company Entity is an individual or entity (“Person”) that is itself, or is controlled by a Person that is currently the subject of any sanctions administered or enforced by the U.S. Department of Treasury’s Office of Foreign Assets Control (“OFAC”) (collectively, “Sanctions”); and the Company represents and covenants that the Company will not, directly or indirectly, use the proceeds of the offering of the Certificates, or lend, contribute or otherwise make available such proceeds to any subsidiary, joint venture partner or other Person (x) to fund or facilitate any activities or business of or with any Person or in any country or territory that, at the time of such funding or facilitation, is the subject of Sanctions, or (y) in any other manner that will result in a violation of Sanctions by any Person (including any Person participating in this offering, whether as underwriter, advisor, investor or otherwise).

(b)    The Depositary represents and warrants to, and agrees with, each Underwriter and the Company that:

(i)    The information pertaining to the Depositary set forth under the caption “Description of the Deposit Agreements—Depositary” (collectively, the “Depositary Information”) in the Time of Sale Prospectus, as amended and supplemented, if the Company shall have furnished any amendment or supplement thereto, does not, and will not as of the Closing Date, contain any untrue statement of a material fact.

(ii)    The Depositary has been duly organized and is validly existing under the laws of Japan and is duly licensed to conduct banking businesses in the State of New York through its New York Branch, with corporate power and authority to own, lease and operate its property, to conduct its business as described in the Depositary Information and to enter into and perform its obligations under this Agreement and the Deposit Agreements.

(iii)    No consent, approval, authorization, or order of, or filing with any governmental agency or body or any court is required for the valid authorization, execution and delivery by the Depositary of this Agreement and the Deposit Agreements and for the consummation of the transactions contemplated herein and therein, except such as may have been obtained.

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(iv)    The execution and delivery by the Depositary of this Agreement and the Deposit Agreements and the consummation of the transactions contemplated herein and therein have been duly authorized by the Depositary and will not violate any law, governmental rule or regulation or any of its organizational documents or any order, writ, injunction or decree of any court or governmental agency against it or the provisions of any indenture, loan agreement, contract or other instrument to which it is a party or is bound.

(v)    This Agreement has been duly authorized, executed and delivered by the Depositary, and the Deposit Agreements will be duly authorized, executed and delivered by the Depositary on or prior to the Closing Date.

(vi)    The Deposit Agreements, when duly authorized, executed and delivered by the Depositary, assuming that such Deposit Agreements have been duly authorized, executed and delivered by, and constitute the legal, valid and binding obligations of, the Escrow Agent, will constitute the legal, valid and binding obligations of the Depositary enforceable in accordance with their terms, except (x) as enforcement thereof may be limited by bankruptcy, insolvency (including, without limitation, all laws relating to fraudulent transfers), reorganization, moratorium or other similar laws now or hereinafter in effect relating to creditors’ rights generally and (y) as enforcement thereof is subject to general principles of equity (regardless of whether enforcement is considered in a proceeding in equity or at law).

(vii)    Payments of interest and principal in respect of the Deposits are not subject to any withholdings or similar charges or deductions which would not be covered by the Depositary’s gross up obligations under Section 4 of the Deposit Agreements.

(c)    The parties agree that any certificate signed by a duly authorized officer of the Company and delivered to an Underwriter, or to counsel for the Underwriters, on the Closing Date and in connection with this Agreement or the offering of the Certificates, shall be deemed a representation and warranty by (and only by) the Company to the Underwriters as to the matters covered thereby.

2.    Purchase, Sale and Delivery of Certificates. (a) On the basis of the representations, warranties and agreements herein contained, but subject to the terms and the conditions herein set forth, the Company agrees to cause the Trustees to sell to each Underwriter, and each Underwriter agrees, severally and not jointly, to purchase from the Trustees, at a purchase price of 100% of the face amount thereof, the aggregate face amount of Certificates of each Pass Through Certificate designation set forth opposite the name of such Underwriter in Schedule II. Concurrently with the issuance of the Certificates, the Escrow Agents shall issue and deliver to the Trustees the Escrow Receipts in accordance with the terms of the Escrow Agreements, which Escrow Receipts shall be attached to the related Certificates.

(b)    The Company is advised by the Representatives that the Underwriters propose to make a public offering of the Certificates as set forth in the Prospectus as soon after

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this Agreement has been entered into as in the judgment of the Representatives is advisable. The Company is further advised by the Representatives that the Certificates are to be offered to the public initially at 100% of their face amount plus accrued interest, if any, from the date of issuance and to certain dealers selected by the Underwriters at concessions not in excess of the concessions set forth in the Prospectus, and that the Underwriters may allow, and such dealers may reallow, concessions not in excess of the concessions set forth in the Prospectus to certain other dealers. The Company acknowledges and agrees that the Underwriters may offer and sell the Securities to or through any affiliate of an Underwriter.

(c)    As underwriting commission and other compensation to the Underwriters for their respective commitments and obligations hereunder in respect of the Certificates, including their respective undertakings to distribute the Certificates, the Company will pay to Citigroup for the accounts of the Underwriters the amount set forth in Schedule III hereto, which amount shall be allocated among the Underwriters in the manner determined by Citigroup and the Company. Such payment will be made by the Company on the Closing Date simultaneously with the issuance and sale of the Certificates (with attached Escrow Receipts) to the Underwriters. Payment of such compensation shall be made by wire transfer of immediately available funds.

(d)     Delivery of and payment for the Certificates (with attached Escrow Receipts) shall be made at the offices of Hughes Hubbard & Reed LLP at One Battery Park Plaza, New York, New York 10004 at 10:00 A.M. on February 11, 2019 or such other date, time and place as may be agreed upon by the Company and Citigroup (such date and time of delivery and payment for the Certificates (with attached Escrow Receipts) being herein called the “Closing Date”). Delivery of the Certificates (with attached Escrow Receipts) issued by each Original Trust shall be made to Citigroup’s account at The Depository Trust Company (“DTC”) for the respective accounts of the several Underwriters against payment by the Underwriters of the purchase price thereof. Payment of the purchase price for the Certificates issued by each Original Trust and the related Escrow Receipts attached thereto shall be made by the Underwriters by wire transfer of immediately available funds to the accounts and in the manner specified in the related Escrow Agreements. The Certificates (with attached Escrow Receipts) issued by each Original Trust shall be in the form of one or more fully registered global certificates, and shall be deposited with the related Trustee as custodian for DTC and registered in the name of Cede & Co.

(e)    The Company agrees to have the Certificates (with attached Escrow Receipts) available for inspection and checking by the Representatives in New York, New York not later than 1:00 P.M. on the business day prior to the Closing Date.

(f)    It is understood that each Underwriter has authorized Citigroup, on its behalf and for its account, to accept delivery of, receipt for, and make payment of the purchase price for, the Certificates (with attached Escrow Receipts) that it has agreed to purchase. Citigroup, individually and not as a Representative, may (but shall not be obligated to) make payment of the purchase price for the Certificates to be purchased by any Underwriter whose check or checks shall not have been received by the Closing Date.

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3.    Conditions of Underwriters’ Obligations. The several obligations of the Underwriters to purchase and pay for the Certificates pursuant to this Agreement are subject to the following conditions:

(a)    On the Closing Date, no stop order suspending the effectiveness of the Registration Statement shall have been issued under the Securities Act and no proceedings therefor shall have been instituted or threatened by the Commission.

(b)    On the Closing Date, the Underwriters shall have received an opinion and negative assurance letter of Hughes Hubbard & Reed LLP, counsel for the Company, dated the Closing Date, in form and substance reasonably satisfactory to the Representatives.

(c)    On the Closing Date, the Underwriters shall have received an opinion of the Senior Managing Counsel — Finance, Fleet & Loyalty of the Company, dated the Closing Date, in form and substance reasonably satisfactory to the Representatives.

(d)    On the Closing Date, the Underwriters shall have received an opinion of Morris James LLP, counsel for Wilmington Trust, National Association, individually and as Trustee, Subordination Agent and Paying Agent, dated the Closing Date, in form and substance reasonably satisfactory to the Representatives.

(e)    On the Closing Date, the Underwriters shall have received an opinion of Sullivan and Worcester LLP, counsel for the Escrow Agent, dated the Closing Date, in form and substance reasonably satisfactory to the Representatives.

(f)    On the Closing Date, the Underwriters shall have received an opinion of special counsel for the Liquidity Provider in the Commonwealth of Australia, dated the Closing Date, in form and substance reasonably satisfactory to the Representatives.

(g)    On the Closing Date, the Underwriters shall have received an opinion of Pillsbury Winthrop Shaw Pittman LLP, special New York counsel for the Liquidity Provider, dated the Closing Date, in form and substance reasonably satisfactory to the Representatives.

(h)    On the Closing Date, the Underwriters shall have received an opinion of Yumoto, Ota & Miyazaki, special Japanese counsel for the Depositary, dated the Closing Date, in form and substance reasonably satisfactory to the Representatives.

(i)    On the Closing Date, the Underwriters shall have received an opinion of Pillsbury Winthrop Shaw Pittman LLP, special New York counsel for the Depositary, dated the Closing Date, in form and substance reasonably satisfactory to the Representatives.

(j)    On the Closing Date, the Underwriters shall have received an opinion and negative assurance letter of Milbank, Tweed, Hadley & McCloy LLP, counsel for the Underwriters, dated the Closing Date, with respect to the issuance and sale of the Certificates, the Registration Statement, the Time of Sale Prospectus, the Prospectus and other related matters as the Underwriters may reasonably require.

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(k)    Subsequent to the execution and delivery of this Agreement, there shall not have occurred any change, or any development or event involving a prospective change, in the condition (financial or other), business, properties or results of operations of the Company and its subsidiaries considered as one enterprise that, in the judgment of the Representatives, is material and adverse and that makes it, in the judgment of the Representatives, impracticable to proceed with the completion of the public offering of the Certificates on the terms and in the manner contemplated by the Time of Sale Prospectus.

(l)    The Underwriters shall have received on the Closing Date a certificate, dated the Closing Date and signed by the President or any Vice President of the Company, to the effect that the representations and warranties of the Company contained in this Agreement are true and correct as of the Closing Date as if made on the Closing Date (except to the extent that they relate solely to an earlier date, in which case they shall be true and accurate as of such earlier date), that the Company has performed all its obligations to be performed hereunder on or prior to the Closing Date and that, subsequent to the execution and delivery of this Agreement, there shall not have occurred any material adverse change, or any development or event involving a prospective material adverse change, in the condition (financial or other), business, properties or results of operations of the Company and its subsidiaries considered as one enterprise, except as set forth in or contemplated by the Time of Sale Prospectus.

(m)    The Underwriters shall have received from Ernst & Young LLP (i) a letter, dated no earlier than the date hereof, in form and substance satisfactory to the Representatives, containing statements and information of the type ordinarily included in accountants’ “comfort letters” to underwriters with respect to the financial statements and certain financial information included or incorporated by reference in the Registration Statement, the preliminary prospectus and the Prospectus, and (ii) a letter, dated the Closing Date, which meets the above requirements, except that the specified date therein referring to certain procedures performed by Ernst & Young LLP will not be a date more than three business days prior to the Closing Date for purposes of this subsection.

(n)    Subsequent to the execution and delivery of this Agreement and prior to the Closing Date, there shall not have been any downgrading in the rating accorded any of the Company’s securities (except for any pass through certificates) by any “nationally recognized statistical rating organization”, as such term is defined in Section 3(a)(62) of the Exchange Act, or any public announcement that any such organization has under surveillance or review, in each case for possible change, its ratings of any such securities other than pass through certificates (other than an announcement with positive implications of a possible upgrading, and no implication of a possible downgrading, of such rating).

(o)    Each of the Appraisers shall have furnished to the Underwriters a letter from such Appraiser, addressed to the Company and dated the Closing Date, confirming that such Appraiser and each of its directors and officers (i) is not an affiliate of the Company or any of its affiliates, (ii) does not have any substantial interest, direct or indirect, in the Company or any of its affiliates and (iii) is not connected with the Company or any of its affiliates as an officer,

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employee, promoter, underwriter, trustee, partner, director or person performing similar functions.

(p)    At the Closing Date, each of the Operative Agreements (other than the Assignment and Assumption Agreements and the Financing Agreements) shall have been duly executed and delivered by each of the parties thereto; and the representations and warranties of the Company contained in each of such executed Operative Agreements shall be true and correct as of the Closing Date (except to the extent that they relate solely to an earlier date, in which case they shall be true and correct as of such earlier date) and the Underwriters shall have received a certificate of the President or a Vice President of the Company, dated as of the Closing Date, to such effect.

(q)    On the Closing Date, the Class AA Certificates and the Class A Certificates shall have received the ratings indicated in the free writing prospectus identified as Item 2 in Schedule IV hereto from the nationally recognized statistical rating organizations named therein.

(r)    On the Closing Date, the representations and warranties of the Company contained herein shall be true and correct as if made on the Closing Date (except to the extent that they relate solely to an earlier date, in which case they shall be true and correct as of such earlier date); and the statements of the Company and their respective officers made in any certificates delivered pursuant to this Agreement on the Closing Date shall be true and correct on and as of the Closing Date.

(s)    On the Closing Date, the representations and warranties of the Depositary contained in this Agreement shall be true and correct as if made on the Closing Date (except to the extent that they relate solely to an earlier date, in which case they shall be true and correct as of such earlier date).

The Company will furnish the Underwriters with such conformed copies of such opinions, certificates, letters and documents as the Underwriters may reasonably request.

4.    Certain Covenants of the Company. The Company covenants with each Underwriter as follows:

(a)    During the period described in the following sentence of this Section 4(a), the Company shall advise the Representatives promptly of any proposal to amend or supplement the Registration Statement, the Time of Sale Prospectus or the Prospectus (except by documents filed under the Exchange Act) and will not effect such amendment or supplement (except by documents filed under the Exchange Act) without the consent of the Representatives, which consent will not be unreasonably withheld. If, at any time after the public offering of the Certificates, the Prospectus (or in lieu thereof the notice referred to in Rule 173(a) under the Securities Act) is required by law to be delivered in connection with sales of the Certificates by an Underwriter or a dealer, any event shall occur as a result of which it is necessary to amend or supplement the Prospectus so that the statements therein will not, in the light of the circumstances when the Prospectus (or in lieu thereof the notice referred to in Rule 173(a) under the Securities Act) is delivered to a purchaser, contain a material misstatement or omission, or if

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it is necessary to amend the Registration Statement or amend or supplement the Prospectus to comply with law, the Company shall prepare and furnish at its expense to the Underwriters and to the dealers (whose names and addresses the Representatives will furnish to the Company) to which Certificates may have been sold by the Representatives on behalf of the Underwriters and to any other dealers upon request, either amendments or supplements to the Prospectus so that the statements in the Prospectus as so amended or supplemented will not, in the light of the circumstances when the Prospectus (or in lieu thereof the notice referred to in Rule 173(a) under the Securities Act) is delivered to a purchaser, contain a material misstatement or omission, or amendments or supplements to the Registration Statement or the Prospectus so that the Registration Statement or the Prospectus, as so amended or supplemented, will comply with law and cause such amendments or supplements to be filed promptly with the Commission.

(b)    During the period mentioned in paragraph (a) above, the Company shall notify each Underwriter immediately of (i) the effectiveness of any amendment to the Registration Statement, (ii) the transmittal to the Commission for filing of any supplement to the Prospectus or any document that would as a result thereof be incorporated by reference in the Prospectus, (iii) the receipt of any comments from the Commission with respect to the Registration Statement or the Prospectus, (iv) any request by the Commission to the Company for any amendment to the Registration Statement or any supplement to the Prospectus or for additional information relating thereto or to any document incorporated by reference in the Prospectus and (v) receipt by the Company of any notice of the issuance by the Commission of any stop order suspending the effectiveness of the Registration Statement, the suspension of the qualification of the Certificates for offering or sale in any jurisdiction, or the institution or threatening of any proceeding for any of such purposes; and the Company agrees to use every reasonable effort to prevent the issuance of any such stop order and, if any such order is issued, to obtain the lifting thereof at the earliest possible moment and the Company shall endeavor (subject to the proviso to Section 4(g)), in cooperation with the Underwriters, to prevent the issuance of any such stop order suspending such qualification and, if any such order is issued, to obtain the lifting thereof at the earliest possible moment.

(c)    During the period mentioned in paragraph (a) above, the Company will furnish to each Underwriter as many conformed copies of the Registration Statement (as originally filed), the Time of Sale Prospectus, the Prospectus, and all amendments and supplements to such documents (excluding all exhibits and documents filed therewith or incorporated by reference therein) and as many conformed copies of all consents and certificates of experts, in each case as soon as available and in such quantities as each Underwriter reasonably requests.

(d)    Promptly following the execution of this Agreement, the Company will prepare a Prospectus that complies with the Securities Act and that sets forth the face amount of the Certificates and their terms (including, without limitation, terms of the Escrow Receipts attached to the Certificates) not otherwise specified in the preliminary prospectus or the Basic Prospectus included in the Registration Statement, the name of each Underwriter and the face amount of the Certificates that each severally has agreed to purchase, the name of each Underwriter, if any, acting as a representative of the Underwriters in connection with the offering, the price at which the Certificates are to be purchased by the Underwriters from the

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Trustee, any initial public offering price, any selling concession and reallowance and any delayed delivery arrangements, and such other information as the Representatives and the Company deem appropriate in connection with the offering of the Certificates. The Company will timely transmit copies of the Prospectus to the Commission for filing pursuant to Rule 424 under the Securities Act.

(e)    The Company shall furnish to each Underwriter a copy of each free writing prospectus relating to the offering of the Certificates prepared by or on behalf of, used by, or referred to by the Company and shall not use or refer to any proposed free writing prospectus to which the Representatives reasonably object.

(f)    If the Time of Sale Prospectus or any “issuer free writing prospectus” is being used to solicit offers to buy the Certificates at a time when a Prospectus is not yet available to prospective purchasers and any event shall occur or condition exist as a result of which it is necessary to amend or supplement the Time of Sale Prospectus or any “issuer free writing prospectus” in order to make the statements therein, in the light of the circumstances when it is delivered to a prospective purchaser, not misleading in any material respect, or if any event shall occur or condition exist as a result of which the Time of Sale Prospectus or any “issuer free writing prospectus” conflicts with the information contained in the Registration Statement then on file, or if it is necessary to amend or supplement the Time of Sale Prospectus or any “issuer free writing prospectus” to comply with applicable law, the Company shall forthwith prepare, file promptly with the Commission and furnish, at the Company’s expense, to the Underwriters and to the dealers (whose names and addresses the Representatives will furnish to the Company) to which Certificates may have been sold by the Representatives on behalf of the Underwriters and to any other dealers upon request, either amendments or supplements to the Time of Sale Prospectus or such “issuer free writing prospectus” so that the statements in the Time of Sale Prospectus or such “issuer free writing prospectus” as so amended or supplemented will not, in the light of the circumstances when it is delivered to a prospective purchaser, be misleading in any material respect or so that the Time of Sale Prospectus or such “issuer free writing prospectus”, as so amended or supplemented, will no longer conflict with the Registration Statement, or so that the Time of Sale Prospectus or such “issuer free writing prospectus”, as amended or supplemented, will comply with applicable law.

(g)    The Company shall, in cooperation with the Underwriters, endeavor to arrange for the qualification of the Certificates for offer and sale under the applicable securities or “blue sky” laws of such jurisdictions in the United States as the Representatives reasonably designate and will endeavor to maintain such qualifications in effect so long as required for the distribution of such Certificates; provided that the Company shall not be required to (i) qualify as a foreign corporation or as a dealer in securities, (ii) file a general consent to service of process or (iii) subject itself to taxation in any such jurisdiction.

(h)    During the period of ten years after the Closing Date, the Company will promptly furnish to each Underwriter, upon request, copies of all Annual Reports on Form 10-K and any definitive proxy statement of the Company (including any successor by merger of the Company) filed with the Commission; provided that (a) filing such documents with the

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Commission or (b) providing a website address at which such Annual Reports and any such definitive proxy statements may be accessed will satisfy this clause (h).

(i)    If the third anniversary of the initial effective date of the Registration Statement occurs before all the Certificates have been sold by the Underwriters, then prior to the third anniversary, the Company shall file a new shelf registration statement and take any other action necessary to permit the public offering of the Certificates to continue without interruption, in which case references herein to the Registration Statement shall include the new registration statement as it shall become effective.

(j)    Between the date of this Agreement and the Closing Date, the Company shall not, without the prior written consent of the Representatives, offer, sell or enter into any agreement to sell (as public debt securities registered under the Securities Act (other than the Certificates or a class of pass through certificates junior to the Certificates and related equipment notes) or as debt securities which may be resold in a transaction exempt from the registration requirements of the Securities Act in reliance on Rule 144A thereunder and which are marketed through the use of a disclosure document containing substantially the same information as a prospectus for similar debt securities registered under the Securities Act), any equipment notes, pass through certificates, equipment trust certificates or equipment purchase certificates secured by aircraft owned by the Company (or rights relating thereto).

(k)    The Company shall prepare a final term sheet relating to the offering of the Certificates, containing only information that describes the final terms of the Certificates or the offering in a form consented to by the Representatives and shall file such final term sheet within the period required by Rule 433(d)(5)(ii) under the Securities Act following the date the final terms have been established for the offering of the Certificates.

5.    Certain Covenants of the Underwriters. Each Underwriter represents, warrants and covenants that it has not made and will not make any offer relating to the Certificates that would constitute an issuer free writing prospectus; provided that this Section 5 shall not prevent any Underwriter from transmitting or otherwise making use of one or more customary “Bloomberg Screens” to offer the Certificates or convey final pricing terms thereof that contain only information contained in the Time of Sale Prospectus.

6.    Indemnification and Contribution. (a) The Company agrees to indemnify and hold harmless each Underwriter and the affiliates of each Underwriter who have, or are alleged to have, participated in the distribution of the Certificates as underwriters, and each Person, if any, who controls such Underwriter, within the meaning of either Section 15 of the Securities Act or Section 20 of the Exchange Act, from and against any and all losses, claims, damages and liabilities (including, without limitation, any legal or other expenses reasonably incurred by any Underwriter or any such controlling person in connection with defending or investigating any such action or claim) caused by any untrue statement or alleged untrue statement of a material fact contained in the Registration Statement, any preliminary prospectus, the Time of Sale Prospectus, any “issuer free writing prospectus” as defined in Rule 433(h) under the Securities Act, any “issuer information” that the Company has filed, or is required to file, pursuant to Rule 433(d) under the Securities Act or the Prospectus, or any amendment or

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supplement thereto, or caused by any omission or alleged omission to state therein a material fact required to be stated therein or necessary to make the statements therein not misleading, except insofar as any of the aforementioned losses, claims, damages or liabilities are caused by any such untrue statement or omission or alleged untrue statement or omission based upon information furnished to the Company in writing by any Underwriter through the Representatives expressly for use in the Registration Statement, any preliminary prospectus, the Time of Sale Prospectus, any issuer free writing prospectus or the Prospectus, or any amendment or supplement thereto (the “Underwriter Information”) or the Depositary Information.

(b)    Each Underwriter agrees, severally and not jointly, to indemnify and hold harmless the Company, its directors, each of its officers who signed the Registration Statement and each person, if any, who controls the Company, within the meaning of either Section 15 of the Securities Act or Section 20 of the Exchange Act, to the same extent as the foregoing indemnity from the Company to such Underwriter but only with reference to the Underwriter Information provided by such Underwriter.

(c)    In case any proceeding (including any governmental investigation) shall be instituted involving any person in respect of which indemnity may be sought pursuant to either paragraph (a) or (b) above, such person (the “indemnified party”) shall promptly notify the person against whom such indemnity may be sought (the “indemnifying party”) in writing; but the omission so to notify the indemnifying party shall not relieve it from any liability which it may have to any indemnified party otherwise than under such paragraph. The indemnifying party, upon request of the indemnified party, shall, and the indemnifying party may elect to, retain counsel reasonably satisfactory to the indemnified party to represent the indemnified party and any others the indemnifying party may designate in such proceeding and the indemnifying party shall pay the fees and disbursements of such counsel related to such proceeding. In any such proceeding, any indemnified party shall have the right to retain its own counsel, but the fees and expenses of such counsel shall be at the expense of such indemnified party unless (i) the indemnifying party and the indemnified party shall have mutually agreed to the retention of such counsel, (ii) the named parties to any such proceeding (including any impleaded parties) include both the indemnifying party and the indemnified party and representation of both parties by the same counsel would be inappropriate due to actual or potential differing interests between them, or (iii) the indemnifying party shall have failed to retain counsel as required by the prior sentence to represent the indemnified party within a reasonable amount of time. It is understood that the indemnifying party shall not, in connection with any proceeding or related proceedings in the same jurisdiction, be liable for the fees and expenses of more than one separate firm (in addition to any local counsel) for all such indemnified parties and that all such fees and expenses shall be reimbursed as they are incurred. Such firm shall be designated in writing by the Representatives in the case of parties indemnified pursuant to paragraph (a) above and by the Company in the case of parties indemnified pursuant to paragraph (b) above. The indemnifying party shall not be liable for any settlement of any proceeding effected without its written consent, but if settled with such consent or if there be a final judgment for the plaintiff, the indemnifying party agrees to indemnify the indemnified party from and against any loss or liability by reason of such settlement or judgment. Notwithstanding the foregoing sentence, if at any time an indemnified party shall have requested in writing an indemnifying party to reimburse the indemnified party for fees and expenses of counsel as contemplated by the second and third sentences of this

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paragraph (c), the indemnifying party agrees that it shall be liable for any settlement of any proceeding effected without its written consent if (i) such settlement is entered into more than 90 days after receipt by such indemnifying party of the aforesaid request and (ii) such indemnifying party shall not have reimbursed the indemnified party in accordance with such request prior to the date of such settlement, unless such fees and expenses are being disputed in good faith. The indemnifying party at any time may, subject to the last sentence of this paragraph (c), settle or compromise any proceeding described in this paragraph (c), at the expense of the indemnifying party. No indemnifying party shall, without the prior written consent of the indemnified party, effect any settlement of any pending or threatened proceeding in respect of which any indemnified party is or could have been a party and indemnity could have been sought hereunder by such indemnified party, unless such settlement (i) includes an unconditional release of such indemnified party from all liability on claims that are the subject matter of such proceeding and (ii) does not include a statement as to, or an admission of, fault, culpability or a failure to act by or on behalf of an indemnified party.

(d)    To the extent the indemnification provided for in paragraph (a) or (b) of this Section 6 is required to be made but is unavailable to an indemnified party or insufficient in respect of any losses, claims, damages or liabilities referred to therein, then the applicable indemnifying party under such paragraph, in lieu of indemnifying such indemnified party thereunder, shall contribute to the amount paid or payable by such indemnified party as a result of such losses, claims, damages or liabilities (i) in such proportion as is appropriate to reflect the relative benefits received by the Company, on the one hand, and the Underwriters, on the other hand, from the offering of the Certificates or (ii) if the allocation provided by clause (i) above is not permitted by applicable law, in such proportion as is appropriate to reflect not only the relative benefits referred to in clause (i) above but also the relative fault of the Company, on the one hand, and the Underwriters, on the other hand, in connection with the statements or omissions that resulted in such losses, claims, damages or liabilities, as well as any other relevant equitable considerations. The relative benefits received by the Company, on the one hand, and the Underwriters, on the other hand, in connection with the offering of such Certificates shall be deemed to be in the same respective proportions as the proceeds from the offering of such Certificates received by the Original Trusts (before deducting expenses), less total underwriting discounts and commissions received by the Underwriters, and the total underwriting discounts and commissions received by the Underwriters, in each case as set forth on the cover of the Prospectus, bear to the aggregate initial public offering price of such Certificates. The relative fault of the Company, on the one hand, and of the Underwriters, on the other hand, shall be determined by reference to, among other things, whether the untrue or alleged untrue statement of a material fact or the omission or alleged omission to state a material fact relates to information supplied by the Company or information supplied by any Underwriters, and the parties’ relative intent, knowledge, access to information and opportunity to correct or prevent such statement or omission. The Underwriters’ respective obligations to contribute pursuant to this Section 6 are several in proportion to the respective face amount of Certificates they have purchased hereunder, and not joint.

(e)    The Company and the Underwriters agree that it would not be just or equitable if contribution pursuant to this Section 6 were determined by pro rata allocation (even if the Underwriters were treated as one entity for such purpose) or by any other method of

21

allocation that does not take account of the equitable considerations referred to in paragraph (d) above. The amount paid or payable by an indemnified party as a result of the losses, claims, damages and liabilities referred to in paragraph (d) above shall be deemed to include, subject to the limitations set forth above, any legal or other expenses reasonably incurred by such indemnified party in connection with investigating or defending any such action or claim. Notwithstanding the provisions of this Section 6, no Underwriter shall be required to contribute any amount in excess of the amount by which the total price at which the Certificates underwritten by it and distributed to the public were offered to the public exceeds the amount of any damages that such Underwriter has otherwise been required to pay by reason of such untrue or alleged untrue statement or omission or alleged omission. No person guilty of fraudulent misrepresentation (within the meaning of Section 11(f) of the Securities Act) shall be entitled to contribution from any person who was not guilty of such fraudulent misrepresentation.

(f)     The indemnity and contribution provisions contained in this Section 6 and the representations and warranties of the Company contained in this Agreement shall remain operative and in full force and effect regardless of (i) any termination of this Agreement, (ii) any investigation made by or on behalf of any Underwriter or any person controlling any Underwriter or by or on behalf of the Company, its officers or directors or any person controlling the Company, and (iii) acceptance of and payment for any of the Certificates. The remedies provided for in this Section 6 are not exclusive and shall not limit any rights or remedies which may otherwise be available to any indemnified party at law or in equity.

7.    Default of Underwriters. If any Underwriter or Underwriters default in their obligations to purchase Certificates hereunder and the aggregate face amount of the Certificates that such defaulting Underwriter or Underwriters agreed but failed to purchase does not exceed 10% of the total face amount of the Certificates, the Representatives may make arrangements satisfactory to the Company for the purchase of such Certificates by other persons, including any of the non-defaulting Underwriters, but if no such arrangements are made by the Closing Date, the non-defaulting Underwriters shall be obligated severally, in proportion to their respective commitments hereunder, to purchase the Certificates that such defaulting Underwriter or Underwriters agreed but failed to purchase. If any Underwriter or Underwriters so default and the aggregate face amount of the Certificates with respect to which such default or defaults occurs exceeds 10% of the total face amount of the Certificates and arrangements satisfactory to the Representatives and the Company for purchase of such Certificates by other persons are not made within 36 hours after such default, this Agreement will terminate without liability on the part of any non-defaulting Underwriter or the Company, except as provided in Section 6. As used in this Agreement, the term “Underwriter” includes any person substituted for an Underwriter under this Section. Nothing herein will relieve a defaulting Underwriter from liability for its default.

8.    Survival of Certain Representations and Obligations. The respective indemnities, agreements, representations, warranties and other statements of the Company or its officers and of the Underwriters set forth in or made pursuant to this Agreement will remain in full force and effect, regardless of any termination of this Agreement, any investigation, or statement as to the results thereof, made by or on behalf of any Underwriter, the Company or any of their respective representatives, officers or directors or any controlling person and will survive

22

delivery of and payment for the Certificates. If for any reason the purchase of the Certificates by the Underwriters is not consummated, the Company shall remain responsible for the expenses to be paid or reimbursed by it pursuant to Section 10 hereof and the respective obligations of the Company and the Underwriters pursuant to Section 6 hereof shall remain in effect. If the purchase of the Certificates by the Underwriters is not consummated for any reason other than solely because of the occurrence of the termination of the Agreement pursuant to Section 7 or 9 hereof, the Company will reimburse the Underwriters for all out-of-pocket expenses (including reasonable fees and disbursements of counsel) reasonably incurred by the Underwriters in connection with the offering of such Certificates and comply with its obligations under Sections 6 and 10 hereof.

9.    Termination. This Agreement shall be subject to termination by notice given by the Representatives to the Company, if (a) after the execution and delivery of this Agreement and prior to the Closing Date (i) trading generally shall have been materially suspended or materially limited on or by, as the case may be, either of the New York Stock Exchange or the NASDAQ Global Market, (ii) trading of any securities of the Company or United Continental Holdings, Inc. shall have been suspended on any exchange or in any over-the-counter market, (iii) a general moratorium on commercial banking activities in New York shall have been declared by either Federal or New York State authorities, (iv) there shall have occurred any attack on, or outbreak or escalation of hostilities or act of terrorism involving, the United States, or any change in financial markets or any calamity or crisis that, in each case, in the judgment of the Representatives, is material and adverse or (v) there shall have occurred any major disruption of settlements of securities or clearance services in the United States that would materially impair settlement and clearance with respect to the Certificates and (b) in the case of any of the events specified in clauses (a)(i) through (v), such event singly or together with any other such event makes it, in the judgment of the Representatives, impracticable to market the Certificates on the terms and in the manner contemplated in the Time of Sale Prospectus.

10.    Payment of Expenses. As between the Company and the Underwriters, the Company shall pay all expenses incidental to the performance of the Company’s obligations under this Agreement, including the following:

(i)    expenses incurred in connection with (A) qualifying the Certificates for offer and sale under the applicable securities or “blue sky” laws of such jurisdictions in the United States as the Representatives reasonably designate (including filing fees and fees and disbursements of counsel for the Underwriters in connection therewith), (B) endeavoring to maintain such qualifications in effect so long as required for the distribution of such Certificates, (C) the review (if any) of the offering of the Certificates by FINRA, (D) the determination of the eligibility of the Certificates for investment under the laws of such jurisdictions as the Underwriters may designate and (E) the preparation and distribution of any blue sky or legal investment memorandum by Underwriters’ counsel;

(ii)    expenses incurred in connection with the preparation and distribution to the Underwriters and the dealers (whose names and addresses the Underwriters will furnish to the Company) to which Certificates may have been sold by the Underwriters on their behalf and to any other dealers upon request, either of (A) amendments to the

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Registration Statement or amendments or supplements to the Time of Sale Prospectus in order to make the statements therein, in the light of the circumstances when the Prospectus is delivered to a purchaser, not materially misleading or (B) amendments or supplements to the Registration Statement, the Time of Sale Prospectus, or the Prospectus so that the Registration Statement, the Time of Sale Prospectus or the Prospectus, as so amended or supplemented, will comply with law and the expenses incurred in connection with causing such amendments or supplements to be filed promptly with the Commission, all as set forth in Section 4(a) hereof;

(iii)    the expenses incurred in connection with the preparation, printing and filing of the Registration Statement (including financial statements and exhibits), as originally filed and as amended, any preliminary prospectus, the Time of Sale Prospectus, the Prospectus, any issuer free writing prospectus and any amendments and supplements to any of the foregoing, including the filing fees payable to the Commission relating to the Certificates (within the time period required by Rule 456(b)(1), if applicable), and the cost of furnishing copies thereof to the Underwriters and dealers;

(iv)    expenses incurred in connection with the preparation, printing and distribution of this Agreement, the Certificates and the Operative Agreements;

(v)    expenses incurred in connection with the delivery of the Certificates to the Underwriters;

(vi)    reasonable fees and disbursements of the counsel and accountants for the Company;

(vii)    to the extent the Company is so required under any Operative Agreement to which it is a party, the fees and expenses of the Mortgagee, the Subordination Agent, the Paying Agents, the Trustees, the Escrow Agents, the Depositary and the Liquidity Provider and the reasonable fees and disbursements of their respective counsel;

(viii)    fees charged by rating agencies for rating the Certificates (including annual surveillance fees related to the Certificates as long as they are outstanding);

(ix)    all fees and expenses relating to appraisals of the Aircraft;

(x)    all other reasonable out-of-pocket expenses incurred by the Underwriters in connection with the transactions contemplated by this Agreement (excluding the fees and disbursements of Milbank, Tweed, Hadley & McCloy LLP as counsel for the Underwriters); and

(xi)    except as otherwise provided in the foregoing clauses (i) through (x), all other expenses incidental to the performance of the Company’s obligations under this Agreement, other than pursuant to Section 6.

11.    Notices. All communications hereunder shall be in writing and effective only upon receipt and, if sent to the Underwriters, shall be mailed, delivered or sent by facsimile

24

transmission and confirmed to the Underwriters c/o Citigroup Global Markets Inc., 388 Greenwich Street, New York, New York 10013, Attention: Global Structured Transportation Finance, Facsimile: (212) 723-6171 and c/o Credit Suisse Securities (USA) LLC, Eleven Madison Avenue, New York, New York 10010, Facsimile: (212) 325-4296 Attention: LCD-IBCM; and, if sent to the Company, shall be mailed, delivered or sent by facsimile transmission and confirmed to it at 233 S. Wacker Drive, Chicago, Illinois 60606, Attention: Chief Financial Officer and General Counsel, facsimile number (872) 825-0316; and, if sent to the Depositary, shall be mailed, delivered or sent by facsimile transmission and confirmed to it at Sumitomo Mitsui Banking Corporation, 277 Park Avenue, New York, NY 10172, Attention: BCDAD-Agency & Special Product Services, Telephone: (212) 224-4501, Facsimile: AgencyServices@smbcgroup.com; provided, however, that any notice to an Underwriter pursuant to Section 6 shall be sent by facsimile transmission or delivered and confirmed to such Underwriter.

12.    Certain Matters Relating to Certain Underwriters. Notwithstanding anything to the contrary in this Agreement or in any other agreement, arrangement or understanding between the Company and Standard Chartered Bank (“Standard Chartered”), each of the Company and Standard Chartered acknowledges that any liability of any EEA Financial Institution (as defined below) arising under this Agreement, to the extent such liability is unsecured, may be subject to the write-down and conversion powers of an EEA Resolution Authority (as defined below) and agrees and consents to, and acknowledges and agrees to be bound by:

(i)    the application of any write-down or conversion powers by an EEA Resolution Authority to any such liabilities arising hereunder which may be payable by such EFA Financial Institution; and

(ii)    the effects of any Bail-in Action (as defined below) on any such liability, including, if applicable:

“Bail-in Action” means the application of any write-down or conversion powers by an EEA Resolution Authority in respect of any liability of an EEA Financial Institution.

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“EEA Financial Institution” means (1) any credit institution or investment firm established in any EEA Member Country which is subject to the supervision of an EEA Resolution Authority, including Standard Chartered, (2) any entity established in an EEA Member Country which is a parent of an institution described in clause (1) of this definition, or (3) any financial institution established in an EEA Member Country which is a subsidiary of an institution described in clauses (1) or (2) of this definition and is subject to consolidated supervision with its parent.

“EEA Member Country” means any of the member states of the European Union, Iceland, Liechtenstein, and Norway.

“EEA Resolution Authority” means any public administrative authority or any person entrusted with public administrative authority of any EEA Member Country (including any delegee) having responsibility for the resolution of any EEA Financial Institution.

13.    Recognition of the U.S. Special Resolution Regimes. In the event that any Underwriter that is a Covered Entity becomes subject to a proceeding under a U.S. Special Resolution Regime, the transfer from such Underwriter of this Agreement and any interest and obligation in or under this Agreement will be effective to the same extent as the transfer would be effective under the U.S. Special Resolution Regime if this Agreement, and any such interest and obligation, were governed by the laws of the United States or a state of the United States.

In the event that any Underwriter that is a Covered Entity or any BHC Act Affiliate of such Underwriter becomes subject to a proceeding under a U.S. Special Resolution Regime, Default Rights under this Agreement that may be exercised against such Underwriter are permitted to be exercised to no greater extent than such Default Rights could be exercised under the U.S. Special Resolution Regime if this Agreement were governed by the laws of the United States or a state of the United States.

As used in this Section 13:

“BHC Act Affiliate” has the meaning assigned to the term “affiliate” in, and shall be interpreted in accordance with, 12 U.S.C. 1841(k);

“Covered Entity” means any of the following: (i) a “covered entity” as that term is defined in, and interpreted in accordance with, 12 C.F.R. § 252.82(b); (ii) a “covered bank” as that term is defined in, and interpreted in accordance with, 12 C.F.R. § 47.3(b); or (iii) a “covered FSI” as that term is defined in, and interpreted in accordance with, 12 C.F.R. § 382.2(b);

“Default Right” has the meaning assigned to that term in, and shall be interpreted in accordance with, 12 C.F.R. §§ 252.81, 47.2 or 382.1 as applicable;

“U.S. Special Resolution Regime” means each of (i) the Federal Deposit Insurance Act and the regulations promulgated thereunder and (ii) Title II of the Dodd-Frank Wall Street Reform and Consumer Protection Act and the regulations promulgated thereunder.

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14.    Successors. This Agreement will inure to the benefit of and be binding upon the parties hereto and their respective successors and the controlling persons referred to in Section 6, and no other person will have any right or obligation hereunder.

15.    Authority of the Representatives. The Representatives are authorized to act for the several Underwriters in connection with this purchase, and any action under this Agreement taken by the Representatives will be binding upon all the Underwriters.

16.    Patriot Act. In accordance with the requirements of the USA Patriot Act (Title III of Pub. L. 107-56 (signed into law October 26, 2001)), the Underwriters are required to obtain, verify and record information that identifies their respective clients, including the Company, which information may include the name and address of their respective clients, as well as other information that will allow the Underwriters to properly identify their respective clients.

17.    Counterparts. This Agreement may be executed in any number of counterparts, each of which will be deemed to be an original, but all such counterparts shall together constitute one and the same Agreement. Delivery of an executed counterpart of a signature page to this Agreement by telecopier, facsimile or other electronic transmission (i.e., a “.pdf” or “.tif”) shall be effective as delivery of a manually executed counterpart thereof.

18.    APPLICABLE LAW. THIS AGREEMENT SHALL BE GOVERNED BY AND CONSTRUED IN ACCORDANCE WITH THE LAWS OF THE STATE OF NEW YORK.

19.    Submission to Jurisdiction; Venue; Waiver of Jury Trial.

(a)    Each party hereto hereby irrevocably agrees, accepts and submits itself to the exclusive jurisdiction of the courts of the State of New York in the City and County of New York and of the United States District Court for the Southern District of New York, in connection with any legal action, suit or proceeding with respect to any matter relating to or arising out of or in connection with this Agreement. Each of the parties to this Agreement agrees that a final action in any such suit or proceeding shall be conclusive and may be enforced in other jurisdictions by suit on the judgment or in any other lawful manner.

(b)    Each party hereto hereby irrevocably waives, to the fullest extent permitted by applicable law, and agrees not to assert, by stay of motion, as a defense, or otherwise, in any legal action or proceeding brought hereunder in any of the above-named courts, that such action or proceeding is brought in an inconvenient forum, or that venue for the action or proceeding is improper.

(c)    Each party hereto hereby irrevocably waives, to the fullest extent permitted by applicable law, any and all right to trial by jury in any legal proceeding arising out of or relating to this Agreement.

20.    No Fiduciary Duty. The Company hereby acknowledges that in connection with the offering of the Certificates: (a) the Underwriters have acted at arm’s length

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and are not agents of and owe no fiduciary duties to the Company or any other person, (b) the Underwriters owe the Company only those duties and obligations set forth in this Agreement and prior written agreements (to the extent not superseded by this Agreement), if any, and (c) the Underwriters may have interests that differ from those of the Company. The Company acknowledges that the Underwriters and their affiliates may provide financing or other services to parties whose interests may conflict with those of the Company and may enter into transactions in the Company’s common stock or other securities, including the Certificates, for their accounts and their customers’ accounts. The Company acknowledges that it is not relying on the advice of the Underwriters for tax, legal or accounting matters, that it is seeking and will rely on the advice of its own professionals and advisors for such matters and that it will make an independent analysis and decision regarding the offering of the Certificates based upon such advice. The Company agrees that it will determine, without reliance upon the Underwriters or their affiliates, the economic risks and merits, as well as the legal, regulatory, tax and accounting characterizations and consequences, of the transactions herein, and that it is capable of assuming the risks of entering into the transactions described herein. The Company acknowledges that the Underwriters are not in the business of providing tax advice and that it has received tax advice from its own tax advisors with appropriate expertise to assess any tax risks. The Company waives to the full extent permitted by applicable law any claims it may have against the Underwriters arising from an alleged breach of fiduciary duty in connection with the offering of the Certificates.

21.    Headings. The headings of the sections of this Agreement have been inserted for convenience of reference only and shall not be deemed a part of this Agreement.

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If the foregoing is in accordance with the Underwriters’ understanding of our agreement, kindly sign and return to the Company one of the counterparts hereof, whereupon it will become a binding agreement among the Company, the Underwriters and the Depositary in accordance with its terms.

[Signature Page to Underwriting Agreement 2019-1AA/A]

The foregoing Underwriting Agreement

is hereby confirmed and accepted

as of the date first above written

CITIGROUP GLOBAL MARKETS INC.

CREDIT SUISSE SECURITIES (USA) LLC

For themselves and on behalf of the several Underwriters listed in Schedule II hereto.

[Signature Page to Underwriting Agreement 2019-1AA/A]

[Signature Page to Underwriting Agreement 2019-1AA/A]

SCHEDULE I

United Airlines Pass Through Certificates, Series 2019-1

SCHEDULE II

SCHEDULE III

SCHEDULE IV

Free Writing Prospectuses

ANNEX A

Pricing Supplement

Dated January 28, 2019

United Airlines, Inc.

$1,013,070,000

2019-1 Pass Through Trust

Class AA and Class A Pass Through Certificates, Series 2019-1

Pricing Supplement dated January 28, 2019 to the preliminary prospectus supplement dated January 28, 2019 relating to the Class AA Certificates and Class A Certificates referred to below (as supplemented, the “Preliminary Prospectus Supplement”) of United Airlines, Inc. (“United”).

The information in this Pricing Supplement supplements the Preliminary Prospectus Supplement and supersedes the information in the Preliminary Prospectus Supplement to the extent inconsistent with the information in the Preliminary Prospectus Supplement.

Unless otherwise indicated, terms used but not defined herein have the meanings assigned to such terms in the Preliminary Prospectus Supplement.

The issuer has filed a registration statement (including a prospectus) with the SEC for the offering to which this communication relates. Before you invest, you should read the prospectus in that registration statement and other documents the issuer has filed with the SEC for more complete information about the issuer and this offering. You may get these documents for free by visiting EDGAR on the SEC Web site at www.sec.gov. Alternatively, the issuer, any underwriter or any dealer participating in the offering will arrange to send you the prospectus if you request it by calling Citigroup at 1-877-858-5407 or Credit Suisse toll-free at 1-800-221-1037.

Exhibit 4.1

EXECUTION VERSION

TRUST SUPPLEMENT No. 2019-1AA-O

Dated as of February 11, 2019

between

WILMINGTON TRUST, NATIONAL ASSOCIATION

as Trustee,

and

UNITED AIRLINES, INC.

to

PASS THROUGH TRUST AGREEMENT

Dated as of October 3, 2012

$716,625,000

United Airlines Pass Through Trust 2019-1AA-O

4.15% United Airlines Pass Through Certificates, Series 2019-1AA-O

i

TABLE OF CONTENTS

Page

Exhibit A     –     Form of Certificate

Exhibit B     –     DTC Letter of Representations

Exhibit C     –     Form of Assignment and Assumption Agreement

1

This Trust Supplement No. 2019-1AA-O, dated as of February 11, 2019 (herein called the “Trust Supplement”), between United Airlines, Inc., a Delaware corporation (the “Company”), and Wilmington Trust, National Association (the “Trustee”), to the Pass Through Trust Agreement, dated as of October 3, 2012, between the Company (formerly known as Continental Airlines, Inc.) and the Trustee (the “Basic Agreement”).

W I T N E S S E T H:

WHEREAS, the Basic Agreement, unlimited as to the aggregate face amount of Certificates (unless otherwise specified herein, capitalized terms used herein without definition having the respective meanings specified in the Basic Agreement) which may be issued thereunder, has heretofore been executed and delivered;

WHEREAS, the Company is the owner of or has obtained commitments from Boeing for the delivery of nine Boeing 737 MAX 9 aircraft, six Boeing 787-10 aircraft and ten Embraer ERJ 175 LL aircraft (collectively, the “Applicable Aircraft”);

WHEREAS, the Company intends to finance each of the Applicable Aircraft;

WHEREAS, with respect to each Applicable Aircraft, the Company will issue pursuant to an Indenture, on a recourse basis, Equipment Notes to finance a portion of the purchase price of such Applicable Aircraft;

WHEREAS, the Trustee hereby declares the creation of the United Airlines Pass Through Trust 2019-1AA-O (the “Applicable Trust”) for the benefit of the Applicable Certificateholders, and the initial Applicable Certificateholders as the grantors of the Applicable Trust, by their respective acceptances of the Applicable Certificates (as defined below), join in the creation of the Applicable Trust with the Trustee;

WHEREAS, all Certificates to be issued by the Applicable Trust will evidence Fractional Undivided Interests in the Applicable Trust and will convey no rights, benefits or interests in respect of any property other than the Trust Property except for those Certificates to which an Escrow Receipt (as defined below) has been affixed;

WHEREAS, the Escrow Agent and the Underwriters have contemporaneously herewith entered into an Escrow Agreement with the Escrow Paying Agent pursuant to which the Underwriters have delivered to the Escrow Agent the proceeds from the sale of the Applicable Certificates, and have irrevocably instructed the Escrow Agent to withdraw and pay funds from such proceeds upon request and proper certification by the Trustee to purchase Equipment Notes as the conditions set forth in the NPA for such purchase are satisfied from time to time prior to the Delivery Period Termination Date;

WHEREAS, the Escrow Agent on behalf of the Applicable Certificateholders has contemporaneously herewith entered into a Deposit Agreement with the Depositary under which the Deposits referred to therein will be made and from which it will withdraw funds to allow the Trustee to purchase Equipment Notes from time to time prior to the Delivery Period Termination Date;

2

WHEREAS, pursuant to the terms and conditions of the Basic Agreement as supplemented by this Trust Supplement (the “Agreement”) and the NPA, upon the financing of an Applicable Aircraft under the NPA, the Trustee on behalf of the Applicable Trust, using funds withdrawn under the Escrow Agreement, shall purchase one or more Equipment Notes having the same interest rate as, and final maturity date not later than the final Regular Distribution Date of, the Applicable Certificates issued hereunder and shall hold such Equipment Notes in trust for the benefit of the Applicable Certificateholders;

WHEREAS, all of the conditions and requirements necessary to make this Trust Supplement, when duly executed and delivered, a valid, binding and legal instrument in accordance with its terms and for the purposes herein expressed, have been done, performed and fulfilled, and the execution and delivery of this Trust Supplement in the form and with the terms hereof have been in all respects duly authorized; and

WHEREAS, this Trust Supplement is subject to the provisions of the Trust Indenture Act of 1939, as amended, and shall, to the extent applicable, be governed by such provisions.

NOW THEREFORE, in consideration of the premises herein, it is agreed between the Company and the Trustee as follows:

ARTICLE I

THE CERTIFICATES

Section 1.01. The Certificates. There is hereby created a series of Certificates to be issued under the Agreement to be distinguished and known as “United Airlines Pass Through Certificates, Series 2019-1AA-O” (hereinafter defined as the “Applicable Certificates”). Each Applicable Certificate represents a Fractional Undivided Interest in the Applicable Trust created hereby. The Applicable Certificates shall be the only instruments evidencing a Fractional Undivided Interest in the Applicable Trust.

The terms and conditions applicable to the Applicable Certificates are as follows:

(a)    The aggregate face amount of the Applicable Certificates that shall be authenticated under the Agreement (except for Applicable Certificates authenticated and delivered under Sections 3.03, 3.04, 3.05 and 3.06 of the Basic Agreement) is $716,625,000.

(b)    The Regular Distribution Dates with respect to any distribution of Scheduled Payments means February 25 and August 25 of each year, commencing on August 25, 2019 until distribution of all of the Scheduled Payments to be made under the Equipment Notes has been made.

3

(c)    The Special Distribution Dates with respect to the Applicable Certificates means any Business Day on which a Special Payment is to be distributed pursuant to the Agreement.

(d)    At the Escrow Agent’s request under the Escrow Agreement, the Trustee shall affix the corresponding Escrow Receipt to each Applicable Certificate. In any event, any transfer or exchange of any Applicable Certificate shall also effect a transfer or exchange of the related Escrow Receipt. Prior to the Final Distribution, no transfer or exchange of any Applicable Certificate shall be permitted unless the corresponding Escrow Receipt is attached thereto and also is so transferred or exchanged. By acceptance of any Applicable Certificate to which an Escrow Receipt is attached, each Holder of such an Applicable Certificate acknowledges and accepts the restrictions on transfer of the Escrow Receipt set forth herein and in the Escrow Agreement.

(e)    (i)    The Applicable Certificates shall be in the form attached hereto as Exhibit A. Any Person acquiring or accepting an Applicable Certificate or an interest therein will, by such acquisition or acceptance, be deemed to have represented and warranted to and for the benefit of the Company that either (x) no assets of an employee benefit plan subject to Title I of the Employee Retirement Income Security Act of 1974, as amended (“ERISA”), a plan subject to Section 4975 of the Internal Revenue Code of 1986, as amended (the “Code”), or a governmental, church or foreign plan subject to a law that is similar to Title I of ERISA or Section 4975 of the Code (a “Similar Law Plan”) have been used to purchase or hold such Applicable Certificate or an interest therein or (y) the purchase and holding of such Applicable Certificate or an interest therein either (A) in the case of assets of an employee benefit plan subject to Title I of ERISA or a plan subject to Section 4975 of the Code, are exempt from the prohibited transaction restrictions of ERISA and the Code pursuant to one or more prohibited transaction statutory or administrative exemptions or (B) in the case of assets of a Similar Law Plan, will not violate any similar state, local or foreign law.

(ii)    The Applicable Certificates shall be Book-Entry Certificates and shall be subject to the conditions set forth in the Letter of Representations between the Applicable Trust and the Clearing Agency attached as Exhibit B.

(f)    If the purchaser or transferee of an Applicable Certificate or an interest therein is an employee benefit plan subject to Title I of ERISA or a plan subject to Section 4975 of the Code, it will be deemed to represent, warrant and agree that (i) none of United Continental Holdings, Inc., the Company, or the Underwriters, nor any of their affiliates, has provided any investment recommendation or investment advice on which it, or any fiduciary or other person investing the assets of such plan (“Plan Fiduciary”), has relied in connection with its decision to invest in the Applicable Certificates, and they are not otherwise acting as a fiduciary, as defined in Section 3(21) of ERISA or Section 4975(e)(3) of the Code, to such plan or the Plan Fiduciary in connection with such plan’s acquisition of the Applicable Certificates; and (ii) the Plan Fiduciary is exercising its own independent judgment in evaluating the transaction.

4

(g)    The “Participation Agreements” as defined in this Trust Supplement are the “Note Purchase Agreements” referred to in the Basic Agreement.

(h)    The Applicable Certificates are subject to the Intercreditor Agreement, the Deposit Agreement and the Escrow Agreement.

(i)    The Applicable Certificates are entitled to the benefits of the Liquidity Facility.

(j)    The Responsible Party is the Company.

(k)    The date referred to in clause (i) of the definition of the term “PTC Event of Default” in the Basic Agreement is the Final Maturity Date.

(l)    The “particular sections of the Note Purchase Agreement”, for purposes of clause (3) of Section 7.07 of the Basic Agreement, are Section 8.1 of each Participation Agreement.

(m)    The Equipment Notes to be acquired and held in the Applicable Trust, and the related Aircraft and Note Documents, are described in the NPA.

ARTICLE II

DEFINITIONS

Section 2.01. Definitions. For all purposes of the Basic Agreement as supplemented by this Trust Supplement, the following capitalized terms have the following meanings (any term used herein which is defined in both this Trust Supplement and the Basic Agreement shall have the meaning assigned thereto in this Trust Supplement for purposes of the Basic Agreement as supplemented by this Trust Supplement):

Agreement: Has the meaning specified in the recitals hereto.

Aircraft: Means each of the Applicable Aircraft (or Substitute Aircraft) in respect of which a Participation Agreement is to be or is, as the case may be, entered into in accordance with the NPA (or any Substitute Aircraft, including engines therefor, owned by the Company and securing one or more Equipment Notes).

Aircraft Purchase Agreement: Has the meaning specified in the NPA.

Applicable Aircraft: Has the meaning specified in the recitals hereto.

Applicable Certificate: Has the meaning specified in Section 1.01 of this Trust Supplement.

Applicable Certificateholder: Means the Person in whose name an Applicable Certificate is registered on the Register for the Applicable Certificates.

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Applicable Closing Date: Has the meaning specified in Section 5.01(b) of this Trust Supplement.

Applicable Participation Agreement: Has the meaning specified in Section 5.01(b) of this Trust Supplement.

Applicable Trust: Has the meaning specified in the recitals hereto.

Assignment and Assumption Agreement: Means the assignment and assumption agreement substantially in the form of Exhibit C hereto executed and delivered in accordance with Section 7.01 of this Trust Supplement.

Basic Agreement: Has the meaning specified in the first paragraph of this Trust Supplement.

Boeing: Means The Boeing Company.

Business Day: Means any day other than a Saturday, a Sunday or a day on which commercial banks are required or authorized to close in New York, New York, Chicago, Illinois, or, so long as any Applicable Certificate is Outstanding, the city and state in which the Trustee, the Subordination Agent or any Loan Trustee maintains its Corporate Trust Office or receives and disburses funds.

Certificate: Has the meaning specified in the Intercreditor Agreement.

Certificate Buyout Event: Means that a United Bankruptcy Event has occurred and is continuing and either of the following events has occurred: (A) both (i) the 60-day period specified in Section 1110(a)(2)(A) of the U.S. Bankruptcy Code (the “60-Day Period”) has expired and (ii) the Company has not entered into one or more agreements under Section 1110(a)(2)(A) of the U.S. Bankruptcy Code to perform all of its obligations under all of the Indentures or, if it has entered into such agreements, has at any time thereafter failed to cure any default under any of the Indentures in accordance with Section 1110(a)(2)(B) of the U.S. Bankruptcy Code; or (B) prior to the expiry of the 60-Day Period, the Company shall have abandoned any Aircraft.

Class: Has the meaning specified in the Intercreditor Agreement.

Closing Notice: Has the meaning specified in the NPA.

Company: Has the meaning specified in the first paragraph of this Trust Supplement.

Controlling Party: Has the meaning specified in the Intercreditor Agreement.

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Cut-off Date: Means the earlier of (a) the Delivery Period Termination Date and (b) the date on which a Triggering Event occurs.

Delivery Period Termination Date: Means the earlier of (a) November 30, 2019 (provided that, if a labor strike occurs or continues at Boeing or Embraer after the Issuance Date and on or prior to such date referred to in this clause (a), such date shall be extended by adding thereto the number of days that such strike continued in effect after the Issuance Date, but not more than 60 days (such extended number of days, the “Strike Period”)) (provided that the Strike Period shall not include any day of a labor strike (1) at Boeing after the Applicable Trust and the United Airlines Pass Through Trust 2019-1A-O shall have purchased, in accordance with the NPA, Equipment Notes issued to finance the Applicable Aircraft manufactured by Boeing or (2) at Embraer after the Applicable Trust and the United Airlines Pass Through Trust 2019-1A-O shall have purchased, in accordance with the NPA, Equipment Notes issued to finance the Applicable Aircraft manufactured by Embraer), and (b) the date on which Equipment Notes issued with respect to all of the Applicable Aircraft (including any Substitute Aircraft in lieu of any New Applicable Aircraft) have been purchased by the Applicable Trust and the United Airlines Pass Through Trust 2019-1A-O in accordance with the NPA.

Deposit Agreement: Means the Deposit Agreement dated as of February 11, 2019 relating to the Applicable Certificates between the Depositary and the Escrow Agent, as the same may be amended, supplemented or otherwise modified from time to time in accordance with its terms.

Depositary: Means Sumitomo Mitsui Banking Corporation, acting through its New York Branch.

Deposits: Has the meaning specified in the Deposit Agreement.

Distribution Date: Means any Regular Distribution Date or Special Distribution Date as the context requires.

Embraer: Means Embraer S.A.

ERISA: Has the meaning specified in Section 1.01(e) of this Trust Supplement.

Escrow Agent: Means, initially, U.S. Bank National Association and any replacement or successor therefor appointed in accordance with the Escrow Agreement.

Escrow Agreement: Means the Escrow and Paying Agent Agreement dated as of February 11, 2019 relating to the Applicable Certificates, among the Escrow Agent, the Escrow Paying Agent, the Trustee and the Underwriters, as the same may be amended, supplemented or otherwise modified from time to time in accordance with its terms.

Escrow Paying Agent: Means the Person acting as paying agent under the Escrow Agreement.

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Escrow Receipt: Means the receipt substantially in the form annexed to the Escrow Agreement representing a Fractional Undivided Interest in the funds held in escrow thereunder.

Final Distribution: Has the meaning specified in the Escrow Agreement.

Final Maturity Date: Means February 25, 2033.

Final Withdrawal: Has the meaning specified in the Escrow Agreement.

Final Withdrawal Date: Has the meaning specified in the Escrow Agreement.

Final Withdrawal Notice: Has the meaning specified in Section 5.02 of this Trust Supplement.

Indenture: Means each of the separate trust indentures and mortgages relating to the Aircraft, each as specified or described in a Closing Notice delivered pursuant to the NPA or the related Participation Agreement, in each case as the same may be amended, supplemented or otherwise modified from time to time in accordance with its terms.

Intercreditor Agreement: Means the Intercreditor Agreement dated as of February 11, 2019 among the Trustee, the Other Trustees party thereto, the Liquidity Provider, the liquidity provider relating to the Class A Certificates and Wilmington Trust, National Association, as Subordination Agent and as trustee thereunder, as amended, supplemented or otherwise modified from time to time in accordance with its terms.

Investors: Means the Underwriters, together with all subsequent beneficial owners of the Applicable Certificates.

Issuance Date: Has the meaning specified in the NPA.

Liquidity Facility: Means, initially, the Revolving Credit Agreement dated as of February 11, 2019 relating to the Applicable Certificates, between the Liquidity Provider and Wilmington Trust, National Association, as Subordination Agent, as agent and trustee for the Applicable Trust, and, from and after the replacement of such agreement pursuant to the Intercreditor Agreement, the replacement liquidity facility therefor, in each case as amended, supplemented or otherwise modified from time to time in accordance with their respective terms.

Liquidity Provider: Means, initially, National Australia Bank Limited, acting through its New York Branch, and any replacements or successors therefor appointed in accordance with the Intercreditor Agreement.

Make-Whole Amount: Has the meaning specified in any Indenture.

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Note Documents: Means the Equipment Notes with respect to the Applicable Certificates and, with respect to any such Equipment Note, the Indenture and the Participation Agreement relating to such Equipment Note.

Notice of Purchase Withdrawal: Has the meaning specified in the Deposit Agreement.

NPA: Means the Note Purchase Agreement, dated as of the date hereof among the Trustee, the Other Trustees party thereto, the Company, the Escrow Agent, the Escrow Paying Agent and the Subordination Agent, providing for, among other things, the purchase of Equipment Notes by the Trustee on behalf of the Applicable Trust, as the same may be amended, supplemented or otherwise modified from time to time, in accordance with its terms.

Other Agreements: Means (i) the Basic Agreement, as supplemented by Trust Supplement No. 2019-1A-O, dated as of the date hereof relating to United Airlines Pass Through Trust 2019-1A-O, (ii) the Basic Agreement, as supplemented by a Trust Supplement relating to any Additional Trust and (iii) the Basic Agreement, as supplemented by a Trust Supplement relating to any Refinancing Trust.

Other Trustees: Means the trustees under the Other Agreements, and any successor or other trustee appointed as provided therein.

Other Trusts: Means the United Airlines Pass Through Trust 2019-1A-O, an Additional Trust or Trusts, if any, and a Refinancing Trust or Trusts, if any, created by the Other Agreements.

Participation Agreement: Means each Participation Agreement entered into by the Trustee pursuant to the NPA, as the same may be amended, supplemented or otherwise modified in accordance with its terms.

Pool Balance: Means, as of any date, (i) the original aggregate face amount of the Applicable Certificates less (ii) the aggregate amount of all payments made as of such date in respect of such Applicable Certificates or in respect of Deposits other than payments made in respect of interest or premium (including Make-Whole Amount) thereon or reimbursement of any costs or expenses incurred in connection therewith. The Pool Balance as of any date shall be computed after giving effect to any special distribution with respect to unused Deposits, payment of principal of the Equipment Notes or payment with respect to other Trust Property and the distribution thereof to be made on that date.

Pool Factor: Means, as of any Distribution Date, the quotient (rounded to the seventh decimal place) computed by dividing (i) the Pool Balance by (ii) the original aggregate face amount of the Applicable Certificates. The Pool Factor as of any Distribution Date shall be computed after giving effect to any special distribution with respect to unused Deposits, payment of principal of the Equipment Notes or payment with respect to other Trust Property and the distribution thereof to be made on that date.

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Prospectus Supplement: Means the final Prospectus Supplement dated January 28, 2019 relating to the offering of the Applicable Certificates and the Class A Certificates.

Ratings Confirmation: Has the meaning specified in the Intercreditor Agreement.

Related Pass Through Trust Agreement: Means the Basic Agreement, as supplemented by the Trust Supplement No. 2019-1AA-S, dated as of the date hereof relating to the United Airlines Pass Through Trust 2019-1AA-S and entered into by the Company and the Related Trustee, which agreement becomes effective upon the execution and delivery of the Assignment and Assumption Agreement pursuant to Section 7.01 of this Trust Supplement.

Related Trust: Means the United Airlines Pass Through Trust 2019-1AA-S, to be formed under the Related Pass Through Trust Agreement.

Related Trustee: Means the trustee under the Related Pass Through Trust Agreement.

Scheduled Closing Date: Has the meaning specified in the NPA.

Scheduled Payment: Means, with respect to any Equipment Note, (i) any payment of principal or interest on such Equipment Note (other than any such payment which is not in fact received by the Trustee or the Subordination Agent within five days of the date on which such payment is scheduled to be made) or (ii) any payment of interest on the Applicable Certificates with funds drawn under the Liquidity Facility, which payment in any such case represents the installment of principal on such Equipment Note at the stated maturity of such installment, the payment of regularly scheduled interest accrued on the unpaid principal amount of such Equipment Note, or both; provided, however, that any payment of principal, premium (including Make-Whole Amount), if any, or interest resulting from the redemption or purchase of any Equipment Note shall not constitute a Scheduled Payment.

Special Payment: Means any payment (other than a Scheduled Payment) in respect of, or any proceeds of, any Equipment Note or Collateral (as defined in each Indenture).

Substitute Aircraft: Has the meaning specified in the NPA.

Transfer Date: Has the meaning specified in Section 7.01 of this Trust Supplement.

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Triggering Event: Has the meaning assigned to such term in the Intercreditor Agreement.

Trust Property: Means (i) subject to the Intercreditor Agreement, the Equipment Notes held as the property of the Applicable Trust, all monies at any time paid thereon or in respect thereof and all monies due and to become due thereunder, (ii) funds from time to time deposited in the Certificate Account and the Special Payments Account and, subject to the Intercreditor Agreement, any proceeds from the sale by the Trustee pursuant to Article VI of the Basic Agreement of any Equipment Note and (iii) all rights of the Applicable Trust and the Trustee, on behalf of the Applicable Trust, under the Intercreditor Agreement, the Escrow Agreement, the NPA and the Liquidity Facility, including, without limitation, all rights to receive certain payments thereunder, and all monies paid to the Trustee on behalf of the Applicable Trust pursuant to the Intercreditor Agreement or the Liquidity Facility, provided that rights with respect to the Deposits or under the Escrow Agreement, except for the right to direct withdrawals for the purchase of Equipment Notes to be held herein, will not constitute Trust Property.

Trust Supplement: Has the meaning specified in the first paragraph of this trust supplement.

Trustee: Has the meaning specified in the first paragraph of this Trust Supplement.

Underwriters: Means, collectively, Citigroup Global Markets Inc., Credit Suisse Securities (USA) LLC, Goldman Sachs & Co. LLC, Deutsche Bank Securities Inc., Morgan Stanley & Co. LLC, J.P. Morgan Securities LLC, Barclays Capital Inc., Merrill Lynch, Pierce, Fenner & Smith Incorporated, BBVA Securities Inc., BNP Paribas Securities Corp., Credit Agricole Securities (USA) Inc., Standard Chartered Bank and Wells Fargo Securities, LLC.

Underwriting Agreement: Means the Underwriting Agreement related to the Applicable Certificates dated January 28, 2019 among Citigroup Global Markets Inc. and Credit Suisse Securities (USA) LLC, as representatives of the several Underwriters, the Company and the Depositary, as the same may be amended, supplemented or otherwise modified from time to time in accordance with its terms.

United Bankruptcy Event: Has the meaning specified in the Intercreditor Agreement.

ARTICLE III

DISTRIBUTIONS; STATEMENTS TO CERTIFICATEHOLDERS

Section 3.01. Statements to Applicable Certificateholders. (a) On each Distribution Date, the Trustee will include with each distribution to Applicable Certificateholders of a Scheduled Payment or Special Payment, as the case may be, a statement setting forth the information provided below (in the case of a Special Payment, reflecting in part the information

provided by the Escrow Paying Agent under the Escrow Agreement). Such statement shall set forth (per $1,000 face amount Applicable Certificate as to (ii), (iii), (iv) and (v) below) the following information:

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(i)    The aggregate amount of funds distributed on such Distribution Date under the Agreement and under the Escrow Agreement, indicating the amount allocable to each source, including any portion thereof paid by the Liquidity Provider;

(ii)    The amount of such distribution under the Agreement allocable to principal and the amount allocable to premium (including Make-Whole Amount), if any;

(iii)    The amount of such distribution under the Agreement allocable to interest;

(iv)    The amount of such distribution under the Escrow Agreement allocable to interest;

(v)    The amount of such distribution under the Escrow Agreement allocable to unused Deposits, if any; and

(vi)    The Pool Balance and the Pool Factor.

With respect to the Applicable Certificates registered in the name of a Clearing Agency or its nominee, on the Record Date prior to each Distribution Date, the Trustee will request that such Clearing Agency post on its Internet bulletin board a securities position listing setting forth the names of all Clearing Agency Participants reflected on such Clearing Agency’s books as holding interests in the Applicable Certificates on such Record Date. On each Distribution Date, the Trustee will mail to each such Clearing Agency Participant the statement described above and will make available additional copies as requested by such Clearing Agency Participant for forwarding to holders of interests in the Applicable Certificates.

(b)    Within a reasonable period of time after the end of each calendar year but not later than the latest date permitted by law, the Trustee shall furnish to each Person who at any time during such calendar year was an Applicable Certificateholder of record a statement containing the sum of the amounts determined pursuant to clauses (a)(i), (a)(ii), (a)(iii), (a)(iv) and (a)(v) above for such calendar year or, in the event such Person was an Applicable Certificateholder of record during a portion of such calendar year, for such portion of such year, and such other items as are readily available to the Trustee and which an Applicable Certificateholder shall reasonably request as necessary for the purpose of such Applicable Certificateholder’s preparation of its U.S. federal income tax returns. Such statement and such other items shall be prepared on the basis of information supplied to the Trustee by the Clearing Agency Participants and shall be delivered by the Trustee to such Clearing Agency Participants to be available for forwarding by such Clearing Agency Participants to the holders of interests in the Applicable Certificates in the manner described in Section 3.01(a) of this Trust Supplement.

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(c)    If the aggregate principal payments scheduled for a Regular Distribution Date prior to the Delivery Period Termination Date differ from the amount thereof set forth for the Applicable Certificates on page S-39 of the Prospectus Supplement, by no later than the 15th day prior to such Regular Distribution Date, the Trustee shall mail written notice of the actual amount of such scheduled payments to the Applicable Certificateholders of record as of a date within 15 Business Days prior to the date of mailing. If the Trustee has given such notice, the Company shall not give a “Closing Notice” (as defined in the NPA) under the NPA providing for a “Funding Date” (as defined in the NPA) on or after the date the Trustee gives such notice and on or prior to such Regular Distribution Date and shall revoke any Closing Notice previously given that provides for such a Funding Date.

(d)    Promptly following (i) the Delivery Period Termination Date, if there has been any change in the information set forth in clauses (y) and (z) below from that set forth on page S-39 of the Prospectus Supplement, and (ii) the date of any early redemption of, or any default in the payment of principal or interest in respect of, any of the Equipment Notes held in the Applicable Trust, or any Final Withdrawal, the Trustee shall furnish to Applicable Certificateholders of record on such date a statement setting forth (x) the expected Pool Balances for each subsequent Regular Distribution Date following the Delivery Period Termination Date, (y) the related Pool Factors for such Regular Distribution Dates and (z) the expected principal payment schedule of the Equipment Notes, in the aggregate, held as Trust Property at the date of such notice. With respect to the Applicable Certificates registered in the name of a Clearing Agency, on the Delivery Period Termination Date, the Trustee will request from such Clearing Agency a securities position listing setting forth the names of all Clearing Agency Participants reflected on such Clearing Agency’s books as holding interests in the Applicable Certificates on such date. The Trustee will mail to each such Clearing Agency Participant the statement described above and will make available additional copies as requested by such Clearing Agency Participant for forwarding to holders of interests in the Applicable Certificates.

(e)    The Trustee shall provide promptly to the Applicable Certificateholders all material non-confidential information received by the Trustee from the Company.

(f)     This Section 3.01 supersedes and replaces Section 4.03 of the Basic Agreement, with respect to the Applicable Trust.

Section 3.02. Special Payments Account. (a) The Trustee shall establish and maintain on behalf of the Applicable Certificateholders a Special Payments Account as one or more accounts, which shall be non-interest bearing except as provided in Section 4.04 of the Basic Agreement. The Trustee shall hold the Special Payments Account in trust for the benefit of the Applicable Certificateholders and shall make or permit withdrawals therefrom only as provided in the Agreement. On each day when one or more Special Payments are made to the Trustee under the Intercreditor Agreement, the Trustee, upon receipt thereof, shall immediately deposit the aggregate amount of such Special Payments in the Special Payments Account.

(b)     This Section 3.02 supersedes and replaces Section 4.01(b) of the Basic Agreement in its entirety, with respect to the Applicable Trust.

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Section 3.03. Distributions from Special Payments Account. (a) On each Special Distribution Date with respect to any Special Payment or as soon thereafter as the Trustee has confirmed receipt of any Special Payments due on the Equipment Notes held (subject to the Intercreditor Agreement) in the Applicable Trust or realized upon the sale of such Equipment Notes, the Trustee shall distribute out of the Special Payments Account the entire amount of such Special Payment deposited therein pursuant to Section 3.02(a) of this Trust Supplement. There shall be so distributed to each Applicable Certificateholder of record on the Record Date with respect to such Special Distribution Date (other than as provided in Section 7.01 of this Trust Supplement concerning the final distribution) by check mailed to such Applicable Certificateholder, at the address appearing in the Register, such Applicable Certificateholder’s pro rata share (based on the Fractional Undivided Interest in the Applicable Trust held by such Applicable Certificateholder) of the total amount in the Special Payments Account on account of such Special Payment, except that, with respect to Applicable Certificates registered on the Record Date in the name of a Clearing Agency (or its nominee), such distribution shall be made by wire transfer in immediately available funds to the account designated by such Clearing Agency (or such nominee).

(b)    The Trustee shall, at the expense of the Company, cause notice of each Special Payment to be mailed to each Applicable Certificateholder at his address as it appears in the Register. In the event of redemption or purchase of Equipment Notes held in the Applicable Trust, such notice shall be mailed not less than 15 days prior to the Special Distribution Date for the Special Payment resulting from such redemption or purchase, which Special Distribution Date shall be the date of such redemption or purchase. In the case of any other Special Payments, such notice shall be mailed as soon as practicable after the Trustee has confirmed that it has received funds for such Special Payment, stating the Special Distribution Date for such Special Payment which shall occur not less than 15 days after the date of such notice and as soon as practicable thereafter. Notices with respect to a Special Payment mailed by the Trustee shall set forth:

(i)    The Special Distribution Date and the Record Date therefor (except as otherwise provided in Section 7.01 of this Trust Supplement),

(ii)    The amount of the Special Payment for each $1,000 face amount Applicable Certificate and the amount thereof constituting principal, premium (including Make-Whole Amount), if any, and interest,

(iii)    The reason for the Special Payment, and

(iv)    If the Special Distribution Date is the same date as a Regular Distribution Date, the total amount to be received on such date for each $1,000 face amount Applicable Certificate.

If the amount of premium (including Make-Whole Amount), if any, payable upon the redemption or purchase of an Equipment Note has not been calculated at the time that the Trustee mails notice of a Special Payment, it shall be sufficient if the notice sets forth the other amounts to be distributed and states that any premium (including Make-Whole Amount) received will also be distributed.

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If any redemption of the Equipment Notes held in the Applicable Trust is canceled, the Trustee, as soon as possible after learning thereof, shall cause notice thereof to be mailed to each Applicable Certificateholder at its address as it appears on the Register.

(c)     This Section 3.03 supersedes and replaces Section 4.02(b) and Section 4.02(c) of the Basic Agreement in their entirety, with respect to the Applicable Trust.

Section 3.04. Limitation of Liability for Payments. Section 3.09 of the Basic Agreement shall be amended, with respect to the Applicable Trust, by deleting the phrase “the Owner Trustees or the Owner Participants” in the second sentence thereof and adding in lieu thereof “the Liquidity Provider”.

ARTICLE IV

DEFAULT

Section 4.01. Purchase Rights of Certificateholders. (a) By acceptance of its Applicable Certificate, each Applicable Certificateholder agrees that at any time after the occurrence and during the continuation of a Certificate Buyout Event:

(i)     So long as no Additional Certificateholder has elected to exercise its rights to purchase Certificates pursuant to, and given notice of such election in accordance with, this Section 4.01(a) (upon such election and notification thereof, the right specified in this Section 4.01(a)(i) shall be suspended and (x) upon consummation of such purchase pursuant to such election, be terminated with respect to such Certificate Buyout Event, or (y) upon failure to consummate such purchase on the proposed purchase date, such right shall be reinstated), each Class A Certificateholder (other than the Company or any of its Affiliates) shall have the right to purchase, for the purchase price set forth in the Class A Trust Agreement, all, but not less than all, of the Applicable Certificates upon 15 days’ written notice to the Trustee and each other Class A Certificateholder, on the third Business Day next following the expiry of such 15-day notice period, provided that (A) if prior to the end of such 15-day period any other Class A Certificateholder (other than the Company or any of its Affiliates) notifies such purchasing Class A Certificateholder that such other Class A Certificateholder wants to participate in such purchase, then such other Class A Certificateholder (other than the Company or any of its Affiliates) may join with the purchasing Class A Certificateholder to purchase all, but not less than all, of the Applicable Certificates pro rata based on the Fractional Undivided Interest in the Class A Trust held by each such Class A Certificateholder and (B) if prior to the end of such 15-day period any other Class A Certificateholder fails to notify the purchasing Class A Certificateholder of such other Class A Certificateholder’s desire to participate in such a purchase, then such other Class A Certificateholder shall lose its right to purchase the Applicable Certificates pursuant to this Section 4.01(a)(i);

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(ii)    If any Additional Certificates are issued pursuant to one or more Additional Trusts, each Additional Certificateholder (other than the Company or any of its Affiliates) shall have the right (which shall not expire upon any purchase of the Applicable Certificates pursuant to clause (i) above) to purchase all, but not less than all, of the Applicable Certificates, the Class A Certificates and any Additional Certificates ranked senior to the Additional Certificates held by the purchasing Additional Certificateholders upon 15 days’ written notice to the Trustee, the Class A Trustee, any Additional Trustee with respect to Additional Certificates that rank senior to the Additional Certificates held by the purchasing Additional Certificateholders and each other Additional Certificateholder of the same class, on the third Business Day next following the expiry of such 15-day notice period, provided that (A) if prior to the end of such 15-day period any other Additional Certificateholder of such class (other than the Company or any of its Affiliates) notifies such purchasing Additional Certificateholder that such other Additional Certificateholder wants to participate in such purchase, then such other Additional Certificateholder (other than the Company or any of its Affiliates) may join with the purchasing Additional Certificateholder to purchase all, but not less than all, of the Applicable Certificates, the Class A Certificates and such senior Additional Certificates pro rata based on the Fractional Undivided Interest in the applicable Additional Trust held by each such Additional Certificateholder and (B) if prior to the end of such 15-day period any other Additional Certificateholder of such class fails to notify the purchasing Additional Certificateholder of such other Additional Certificateholder’s desire to participate in such a purchase, then such other Additional Certificateholder shall lose its right to purchase the Applicable Certificates, the Class A Certificates and such senior Additional Certificates pursuant to this Section 4.01(a)(ii); and

(iii)    If any Refinancing Certificates are issued, each Refinancing Certificateholder shall have the same right (subject to the same terms and conditions) to purchase Certificates pursuant to this Section 4.01(a) (and to receive notice in connection therewith) as the Certificateholders of the Class that such Refinancing Certificates refinanced.

The purchase price with respect to the Applicable Certificates shall be equal to the Pool Balance of the Applicable Certificates, together with accrued and unpaid interest thereon to the date of such purchase, without premium (including Make-Whole Amount), but including any other amounts then due and payable to the Applicable Certificateholders under the Agreement, the Intercreditor Agreement, the Escrow Agreement or any Note Document or on or in respect of the Applicable Certificates; provided, however, that no such purchase of Applicable Certificates shall be effective unless the purchaser(s) shall certify to the Trustee that contemporaneously with such purchase, such purchaser(s) is (are) purchasing, pursuant to the terms of the Agreement and the Other Agreements, all of the Applicable Certificates, the Class A Certificates (unless such purchaser is a Class A Certificateholder) and, if applicable, the Additional Certificates that rank senior to the Additional Certificates held by the purchasing Additional Certificateholder(s). Each payment of the purchase price of the Applicable Certificates referred to in the first sentence hereof shall be made to an account or accounts designated by the Trustee and each such purchase shall be subject to the terms of this Section 4.01. Each Applicable Certificateholder agrees by its acceptance of its Applicable Certificate that (at any time after the occurrence of a Certificate Buyout Event) it will, upon payment from such Class A Certificateholder(s), Additional Certificateholder(s) or Refinancing Certificateholder(s), as the case may be, of the purchase price set forth in the first sentence of this paragraph, (i) forthwith sell, assign, transfer and convey to

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the purchaser(s) thereof (without recourse, representation or warranty of any kind except for its own acts), all of the right, title, interest and obligation of such Applicable Certificateholder in the Agreement, the Escrow Agreement, the Deposit Agreement, the Intercreditor Agreement, the Liquidity Facility, the NPA, the Note Documents and all Applicable Certificates and Escrow Receipts held by such Applicable Certificateholder (excluding all right, title and interest under any of the foregoing to the extent such right, title or interest is with respect to an obligation not then due and payable as respects any action or inaction or state of affairs occurring prior to such sale) (and the purchaser shall assume all of such Applicable Certificateholder’s obligations under the Agreement, the Escrow Agreement, the Deposit Agreement, the Intercreditor Agreement, the Liquidity Facility, the NPA, the Note Documents and all such Applicable Certificates and Escrow Receipts), (ii) if such purchase occurs after a record date specified in Section 2.03 of the Escrow Agreement relating to the distribution of unused Deposits and/or accrued and unpaid interest on Deposits and prior to or on the related distribution date thereunder, forthwith turn over to the purchaser(s) of its Applicable Certificate all amounts, if any, received by it on account of such distribution, and (iii) if such purchase occurs after a Record Date relating to any distribution and prior to or on the related Distribution Date, forthwith turn over to the purchaser(s) of its Applicable Certificate all amounts, if any, received by it on account of such distribution. The Applicable Certificates will be deemed to be purchased on the date payment of the purchase price is made notwithstanding the failure of the Applicable Certificateholders to deliver any Applicable Certificates and, upon such a purchase, (I) the only rights of the Applicable Certificateholders will be to deliver the Applicable Certificates to the purchaser(s) and receive the purchase price for such Applicable Certificates and (II) if the purchaser(s) shall so request, such Applicable Certificateholder will comply with all the provisions of Section 3.04 of the Basic Agreement to enable new Applicable Certificates to be issued to the purchaser in such denominations as it shall request. All charges and expenses in connection with the issuance of any such new Applicable Certificates shall be borne by the purchaser thereof.

As used in this Section 4.01 and elsewhere in this Trust Supplement, the terms “Additional Certificate”, “Additional Certificateholder”, “Additional Equipment Notes”, “Additional Trust”, “Class A Certificate”, “Class A Certificateholder”, “Class A Trust”, “Class A Trust Agreement”, “Class A Trustee”, “Refinancing Certificates”, “Refinancing Certificateholder”, “Refinancing Equipment Notes” and “Refinancing Trust” shall have the respective meanings assigned to such terms in the Intercreditor Agreement.

(b)    This Section 4.01 supersedes and replaces Section 6.01(b) of the Basic Agreement, with respect to the Applicable Trust.

Section 4.02. Amendment of Section 6.05 of the Basic Agreement. Section 6.05 of the Basic Agreement shall be amended, with respect to the Applicable Trust, by deleting the phrase “and thereby annul any Direction given by such Certificateholders or the Trustee to such Loan Trustee with respect thereto,” set forth in the first sentence thereof.

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ARTICLE V

THE TRUSTEE

Section 5.01. Delivery of Documents; Delivery Dates. (a) The Trustee is hereby directed (i) to execute and deliver the Intercreditor Agreement, the Escrow Agreement and the NPA on or prior to the Issuance Date, each in the form delivered to the Trustee by the Company, and (ii) subject to the respective terms thereof, to perform its obligations thereunder. Upon request of the Company and the satisfaction or waiver of the closing conditions specified in the Underwriting Agreement, the Trustee shall execute, deliver, authenticate, issue and sell Applicable Certificates in authorized denominations equaling in the aggregate the amount set forth, with respect to the Applicable Trust, in Schedule I to the Underwriting Agreement evidencing the entire ownership interest in the Applicable Trust, which amount equals the maximum aggregate principal amount of Equipment Notes which may be purchased by the Trustee pursuant to the NPA. Except as provided in Sections 3.03, 3.04, 3.05 and 3.06 of the Basic Agreement, the Trustee shall not execute, authenticate or deliver Applicable Certificates in excess of the aggregate amount specified in this paragraph. The provisions of this Section 5.01(a) supersede and replace the first sentence of Section 3.02(a) of the Basic Agreement, with respect to the Applicable Trust.

(b)    After the Issuance Date, the Company may deliver from time to time to the Trustee a Closing Notice relating to one or more Equipment Notes. After receipt of a Closing Notice and in any case no later than one Business Day prior to a Scheduled Closing Date as to which such Closing Notice relates (the “Applicable Closing Date”), the Trustee shall (as and when specified in the Closing Notice) instruct the Escrow Agent to provide a Notice of Purchase Withdrawal to the Depositary requesting (i) the withdrawal of one or more Deposits on the Applicable Closing Date in accordance with and to the extent permitted by the terms of the Escrow Agreement and the Deposit Agreement and (ii) the payment of all, or a portion, of such Deposit or Deposits in an amount equal in the aggregate to the purchase price of such Equipment Notes to or on behalf of the Company, all as shall be described in the Closing Notice. The Trustee shall (as and when specified in such Closing Notice), subject to the conditions set forth in Section 2 of the NPA, enter into and perform its obligations under the Participation Agreement specified in such Closing Notice (the “Applicable Participation Agreement”) and cause such certificates, documents and legal opinions relating to the Trustee to be duly delivered as required by the Applicable Participation Agreement. If at any time prior to the Applicable Closing Date, the Trustee receives a notice of postponement pursuant to Section 1(e) or 1(f) of the NPA, then the Trustee shall give the Depositary (with a copy to the Escrow Agent) a notice of cancellation of such Notice of Purchase Withdrawal relating to such Deposit or Deposits on such Applicable Closing Date. Upon satisfaction of the conditions specified in the NPA and the Applicable Participation Agreement, the Trustee shall purchase the applicable Equipment Notes with the proceeds of the withdrawals of one or more Deposits made on the Applicable Closing Date in accordance with the terms of the Deposit Agreement and the Escrow Agreement. The purchase price of such Equipment Notes shall equal the principal amount of such Equipment Notes. Amounts withdrawn from such Deposit or Deposits in excess of the purchase price of the Equipment Notes or to the extent not applied on the Applicable Closing Date to the purchase price of the Equipment Notes, shall be re-deposited by the Trustee with the Depositary on the Applicable Closing Date in accordance with the terms of the Deposit Agreement. The provisions of this Section 5.01(b) supersede and replace the provisions of Section 2.02 of the Basic Agreement with respect to the Applicable Trust, and all provisions of the Basic Agreement relating to Postponed Notes and Section 2.02 of the Basic Agreement shall not apply to the Applicable Trust.

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(c)     The Trustee acknowledges its acceptance of all right, title and interest in and to the Trust Property to be acquired pursuant to Section 5.01(b) of this Trust Supplement, the NPA and each Applicable Participation Agreement, and declares that it holds and will hold such right, title and interest for the benefit of all present and future Applicable Certificateholders, upon the trusts set forth in the Agreement. By its acceptance of an Applicable Certificate, each initial Applicable Certificateholder, as a grantor of the Applicable Trust, joins with the Trustee in the creation of the Applicable Trust. The provisions of this Section 5.01(c) supersede and replace the provisions of Section 2.03 of the Basic Agreement, with respect to the Applicable Trust.

Section 5.02. Withdrawal of Deposits. If any Deposits remain outstanding on the Business Day next succeeding the Cut-off Date, the Trustee shall promptly give the Escrow Agent notice that the Trustee’s obligation to purchase Equipment Notes under the NPA has terminated and instruct the Escrow Agent to provide a notice of Final Withdrawal to the Depositary substantially in the form of Exhibit B to the Deposit Agreement (the “Final Withdrawal Notice”).

Section 5.03. The Trustee. (a) Subject to Section 5.04 of this Trust Supplement and Section 7.15 of the Basic Agreement, the Trustee shall not be responsible in any manner whatsoever for or in respect of the validity or sufficiency of this Trust Supplement, the Deposit Agreement, the NPA or the Escrow Agreement or the due execution hereof or thereof by the Company or the other parties thereto (other than the Trustee), or for or in respect of the recitals and statements contained herein or therein, all of which recitals and statements are made solely by the Company, except that the Trustee hereby represents and warrants that each of this Trust Supplement, the Basic Agreement, each Applicable Certificate, the Intercreditor Agreement, the NPA and the Escrow Agreement has been executed and delivered by one of its officers who is duly authorized to execute and deliver such document on its behalf.

(b)    Except as herein otherwise provided and except during the continuation of an Event of Default in respect of the Applicable Trust created hereby, no duties, responsibilities or liabilities are assumed, or shall be construed to be assumed, by the Trustee by reason of this Trust Supplement other than as set forth in the Agreement, and this Trust Supplement is executed and accepted on behalf of the Trustee, subject to all the terms and conditions set forth in the Agreement, as fully to all intents as if the same were herein set forth at length.

Section 5.04. Representations and Warranties of the Trustee. The Trustee hereby represents and warrants that:

(a)    The Trustee has full power, authority and legal right to execute, deliver and perform this Trust Supplement, the Intercreditor Agreement, the Escrow Agreement, the NPA and the Note Documents to which it is or is to become a party and has taken all necessary action to authorize the execution, delivery and performance by it of this Trust Supplement, the Intercreditor Agreement, the Escrow Agreement, the NPA and the Note Documents to which it is or is to become a party;

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(b)    The execution, delivery and performance by the Trustee of this Trust Supplement, the Intercreditor Agreement, the Escrow Agreement, the NPA and the Note Documents to which it is or is to become a party (i) will not violate any provision of any United States federal law or the law of the state of the United States where it is located governing the banking and trust powers of the Trustee or any order, writ, judgment, or decree of any court, arbitrator or governmental authority applicable to the Trustee or any of its assets, (ii) will not violate any provision of the articles of association or by-laws of the Trustee, and (iii) will not violate any provision of, or constitute, with or without notice or lapse of time, a default under, or result in the creation or imposition of any lien on any properties included in the Trust Property pursuant to the provisions of any mortgage, indenture, contract, agreement or other undertaking to which it is a party, which violation, default or lien could reasonably be expected to have an adverse effect on the Trustee’s performance or ability to perform its duties hereunder or thereunder or on the transactions contemplated herein or therein;

(c)    The execution, delivery and performance by the Trustee of this Trust Supplement, the Intercreditor Agreement, the Escrow Agreement, the NPA and the Note Documents to which it is or is to become a party will not require the authorization, consent, or approval of, the giving of notice to, the filing or registration with, or the taking of any other action in respect of, any governmental authority or agency of the United States or the state of the United States where it is located regulating the banking and corporate trust activities of the Trustee; and

(d)    This Trust Supplement, the Intercreditor Agreement, the Escrow Agreement, the NPA and the Note Documents to which it is or is to become a party have been, or will be, as applicable, duly executed and delivered by the Trustee and constitute, or will constitute, as applicable, the legal, valid and binding agreements of the Trustee, enforceable against it in accordance with their respective terms; provided, however, that enforceability may be limited by (i) applicable bankruptcy, insolvency, reorganization, moratorium or similar laws affecting the rights of creditors generally and (ii) general principles of equity.

Section 5.05. Trustee Liens. The Trustee in its individual capacity agrees, in addition to the agreements contained in Section 7.17 of the Basic Agreement, that it will at its own cost and expense promptly take any action as may be necessary to duly discharge and satisfy in full any Trustee’s Liens on or with respect to the Trust Property which is attributable to the Trustee in its individual capacity and which is unrelated to the transactions contemplated by the Intercreditor Agreement or the NPA.

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ARTICLE VI

ADDITIONAL AMENDMENT; SUPPLEMENTAL AGREEMENTS

Section 6.01. Amendment of Section 5.02 of the Basic Agreement. Section 5.02 of the Basic Agreement shall be amended, with respect to the Applicable Trust, by (i) replacing the phrase “of the Note Documents and of this Agreement” set forth in paragraph (b) thereof with the phrase “of the Note Documents, of the NPA and of this Agreement” and (ii) replacing the phrase “of this Agreement and any Note Document” set forth in the last paragraph of Section 5.02 with the phrase “of this Agreement, the NPA and any Note Document”.

Section 6.02. Supplemental Agreements without Consent of Applicable Certificateholders. Without limitation of Section 9.01 of the Basic Agreement, under the terms of, and subject to the limitations contained in, Section 9.01 of the Basic Agreement, the Company may (but will not be required to), and the Trustee (subject to Section 9.03 of the Basic Agreement) shall, at the Company’s request, at any time and from time to time:

(i)     Enter into one or more agreements supplemental to the Escrow Agreement, the NPA or the Deposit Agreement for any of the purposes set forth in clauses (1) through (9) of such Section 9.01, and (without limitation of the foregoing or Section 9.01 of the Basic Agreement) (a) clauses (2) and (3) of such Section 9.01 shall also be deemed to include the Company’s obligations under (in the case of clause (2)), and the Company’s rights and powers conferred by (in the case of clause (3)), the NPA, and (b) references in clauses (4), (6) and (7) of such Section 9.01 to “any Intercreditor Agreement or any Liquidity Facility” shall also be deemed to refer to “the Intercreditor Agreement, the Liquidity Facility, the Escrow Agreement, the NPA or the Deposit Agreement”,

(ii)    Enter into one or more agreements supplemental to the Agreement, the Intercreditor Agreement or the NPA to provide for the formation of one or more Additional Trusts, the issuance of Additional Certificates, the purchase by an Additional Trust (if any) of applicable Additional Equipment Notes and other matters incidental thereto or otherwise contemplated by Section 2.01(b) of the Basic Agreement, subject to the provisions of Section 4(a)(vi) of the NPA and Section 9.1(d) of the Intercreditor Agreement, and

(iii)     Enter into one or more agreements supplemental to the Agreement to provide for the formation of one or more Refinancing Trusts, the issuance of Refinancing Certificates, the purchase by any Refinancing Trust of applicable Refinancing Equipment Notes and other matters incidental thereto or as otherwise contemplated by Section 2.01(b) of the Basic Agreement, subject to the provisions of Section 4(a)(vi) of the NPA and Section 9.1(c) of the Intercreditor Agreement.

Section 6.03. Supplemental Agreements with Consent of Applicable Certificateholders. Without limitation of Section 9.02 of the Basic Agreement, the provisions of Section 9.02 of the Basic Agreement shall apply to agreements or amendments for the purpose of adding any provisions to or changing in any manner or eliminating any of the provisions of the Escrow Agreement, the Deposit Agreement, the Liquidity Facility or the NPA or modifying in any manner the rights and obligations of the Applicable Certificateholders under the Escrow Agreement, the Deposit Agreement, the Liquidity Facility or the NPA; provided that the provisions of Section 9.02(1) of the Basic Agreement shall be deemed to include reductions in any manner of, or delay in the timing of, any receipt by the Applicable Certificateholders of payments upon the Deposits.

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Section 6.04. Consent of Holders of Certificates Issued under Other Trusts. Notwithstanding any provision in Section 6.02 or Section 6.03 of this Trust Supplement to the contrary, no amendment or modification of Section 4.01 of this Trust Supplement shall be effective unless the trustee for each Class of Certificates affected by such amendment or modification shall have consented thereto.

ARTICLE VII

TERMINATION OF TRUST

Section 7.01. Termination of the Applicable Trust. (a) The respective obligations and responsibilities of the Company and the Trustee with respect to the Applicable Trust shall terminate upon the earlier of (i) the completion of the assignment, transfer and discharge described in the first sentence of the immediately following paragraph and (ii) distribution to all Applicable Certificateholders and the Trustee of all amounts required to be distributed to them pursuant to the Agreement and the disposition of all property held as part of the Trust Property; provided, however, that in no event shall the Applicable Trust continue beyond one hundred ten (110) years following the date of the execution of this Trust Supplement.

Upon the earlier of (i) the first Business Day following November 30, 2019 or, if later, the fifth Business Day following the Delivery Period Termination Date and (ii) the fifth Business Day following the date on which a Triggering Event occurs (such date, the “Transfer Date”), or, if later, the date on which all of the conditions set forth in the immediately following sentence have been satisfied, the Trustee is hereby directed (subject only to the immediately following sentence) to, and the Company shall direct the institution that will serve as the Related Trustee under the Related Pass Through Trust Agreement to, execute and deliver the Assignment and Assumption Agreement, pursuant to which the Trustee shall assign, transfer and deliver all of the Trustee’s right, title and interest to the Trust Property to the Related Trustee under the Related Pass Through Trust Agreement. The Trustee and the Related Trustee shall execute and deliver the Assignment and Assumption Agreement upon the satisfaction of the following conditions:

(i)    The Trustee, the Related Trustee and each of the Rating Agencies then rating the Applicable Certificates shall have received an Officer’s Certificate and an Opinion of Counsel dated the date of the Assignment and Assumption Agreement and each satisfying the requirements of Section 1.02 of the Basic Agreement, which Opinion of Counsel shall be substantially to the effect set forth below and may be relied upon by the Beneficiaries (as defined in the Assignment and Assumption Agreement):

(I)    Upon the execution and delivery thereof by the parties thereto in accordance with the terms of the Agreement and the Related Pass Through Trust Agreement, the Assignment and Assumption Agreement will constitute the valid and binding obligation of each of the parties thereto enforceable against each such party in accordance with its terms;

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(II)    Upon the execution and delivery of the Assignment and Assumption Agreement in accordance with the terms of the Agreement and the Related Pass Through Trust Agreement, each of the Applicable Certificates then Outstanding will be entitled to the benefits of the Related Pass Through Trust Agreement;

(III)    The Related Trust is not required to be registered as an investment company under the Investment Company Act of 1940, as amended;

(IV)    The Related Pass Through Trust Agreement constitutes the valid and binding obligation of the Company enforceable against the Company in accordance with its terms; and

(V)    Neither the execution and delivery of the Assignment and Assumption Agreement in accordance with the terms of the Agreement and the Related Pass Through Trust Agreement, nor the consummation by the parties thereto of the transactions contemplated to be consummated thereunder on the date thereof, will violate any law or governmental rule or regulation of the State of New York or the United States of America known to such counsel to be applicable to the transactions contemplated by the Assignment and Assumption Agreement.

(ii)    The Trustee and the Company shall have received (x) a copy of the articles of incorporation and bylaws of the Related Trustee certified as of the Transfer Date by the Secretary or Assistant Secretary of such institution and (y) a copy of the filing (including all attachments thereto) made by the institution serving as the Related Trustee with the Office of the Superintendent, State of New York Banking Department for the qualification of the Related Trustee under Section 131(3) of the New York Banking Law, if applicable to such Related Trustee.

Upon the execution of the Assignment and Assumption Agreement by the parties thereto, the Applicable Trust shall be terminated, the Applicable Certificateholders shall receive beneficial interests in the Related Trust in exchange for their interests in the Applicable Trust equal to their respective beneficial interests in the Applicable Trust, and the Outstanding Applicable Certificates representing Fractional Undivided Interests in the Applicable Trust shall be deemed for all purposes of the Agreement and the Related Pass Through Trust Agreement, without further signature or action of any party or Applicable Certificateholder, to be certificates representing the same Fractional Undivided Interests in the Related Trust and its trust property. By acceptance of its Applicable Certificate, each Applicable Certificateholder consents to such assignment, transfer and delivery of the Trust Property to the trustee of the Related Trust upon the execution and delivery of the Assignment and Assumption Agreement.

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In connection with the occurrence of the event set forth in clause (ii) above of the first paragraph of this Section 7.01(a), notice of such termination, specifying the Distribution Date upon which the Applicable Certificateholders may surrender their Applicable Certificates to the Trustee for payment of the final distribution and cancellation, shall be mailed promptly by the Trustee to Applicable Certificateholders not earlier than the 60th day and not later than the 15th day next preceding such final Distribution Date specifying (A) the Distribution Date upon which the proposed final payment of the Applicable Certificates will be made upon presentation and surrender of Applicable Certificates at the office or agency of the Trustee therein specified, (B) the amount of any such proposed final payment, and (C) that the Record Date otherwise applicable to such Distribution Date is not applicable, payments being made only upon presentation and surrender of the Applicable Certificates at the office or agency of the Trustee therein specified. The Trustee shall give such notice to the Registrar at the time such notice is given to Applicable Certificateholders. Upon presentation and surrender of the Applicable Certificates in accordance with such notice, the Trustee shall cause to be distributed to Applicable Certificateholders such final payments.

In the event that all of the Applicable Certificateholders shall not surrender their Applicable Certificates for cancellation within six months after the date specified in the above-mentioned written notice, the Trustee shall give a second written notice to the remaining Applicable Certificateholders to surrender their Applicable Certificates for cancellation and receive the final distribution with respect thereto. No additional interest shall accrue on the Applicable Certificates after the Distribution Date specified in the first written notice. In the event that any money held by the Trustee for the payment of distributions on the Applicable Certificates shall remain unclaimed for two years (or such lesser time as the Trustee shall be satisfied, after sixty days’ notice from the Company, is one month prior to the escheat period provided under applicable law) after the final distribution date with respect thereto, the Trustee shall pay to each Loan Trustee the appropriate amount of money relating to such Loan Trustee and shall give written notice thereof to the Company.

(b)     The provisions of this Section 7.01 supersede and replace the provisions of Section 11.01 of the Basic Agreement in its entirety, with respect to the Applicable Trust.

ARTICLE VIII

MISCELLANEOUS PROVISIONS

Section 8.01. Basic Agreement Ratified. Except and so far as herein expressly provided, all of the provisions, terms and conditions of the Basic Agreement are in all respects ratified and confirmed; and the Basic Agreement and this Trust Supplement shall be taken, read and construed as one and the same instrument. All replacements of provisions of, and other modifications of the Basic Agreement set forth in this Trust Supplement are solely with respect to the Applicable Trust.

Section 8.02. GOVERNING LAW. THE AGREEMENT AND, UNTIL THE TRANSFER DATE, THE APPLICABLE CERTIFICATES SHALL BE GOVERNED BY AND CONSTRUED IN ACCORDANCE WITH THE LAWS OF THE STATE OF DELAWARE. THIS SECTION 8.02 SUPERSEDES AND REPLACES SECTION 12.05 OF THE BASIC AGREEMENT, WITH RESPECT TO THE APPLICABLE TRUST.

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Section 8.03. Execution in Counterparts. This Trust Supplement may be executed in any number of counterparts, each of which shall be an original, but such counterparts shall together constitute but one and the same instrument.

Section 8.04. Intention of Parties. The parties hereto intend that the Applicable Trust be classified for U.S. federal income tax purposes as a grantor trust under Subpart E, Part I of Subchapter J of the Internal Revenue Code of 1986, as amended, and not as a trust or association taxable as a corporation or as a partnership. Each Applicable Certificateholder and Investor, by its acceptance of its Applicable Certificate or a beneficial interest therein, agrees to treat the Applicable Trust as a grantor trust for all U.S. federal, state and local income tax purposes. The powers granted and obligations undertaken pursuant to the Agreement shall be so construed so as to further such intent.

IN WITNESS WHEREOF, the Company and the Trustee have caused this Trust Supplement to be duly executed by their respective officers thereto duly authorized, as of the day and year first written above.

Signature Page to Class AA-O Trust Supplement 19-1

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EXHIBIT A

FORM OF CERTIFICATE

Certificate

No.                 

[Unless this certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to Issuer or its agent for registration of transfer, exchange or payment, and any certificate issued is registered in the name of Cede & Co. or in such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch the registered owner hereof, Cede & Co., has an interest herein.]^*

UNITED AIRLINES PASS THROUGH TRUST 2019-1AA-O

United Airlines Pass Through Certificate, Series 2019-1AA-O

Issuance Date:    February 11, 2019

Final Maturity Date: February 25, 2033

Evidencing A Fractional Undivided Interest In The United Airlines Pass Through Trust 2019-1AA-O, The Property Of Which Shall Include Certain Equipment Notes Each Secured By An Aircraft Owned By United Airlines, Inc.

$[_____________] Fractional Undivided Interest

representing 0.000139543% of the Trust per $1,000 face amount

THIS CERTIFIES THAT __________, for value received, is the registered owner of a $___________ (___________________________________________________ DOLLARS) Fractional Undivided Interest in the United Airlines Pass Through Trust 2019-1AA-O (the “Trust”) created by Wilmington Trust, National Association, as trustee (the “Trustee”), pursuant to a Pass Through Trust Agreement, dated as of October 3, 2012 (the “Basic Agreement”), between the Trustee and United Airlines, Inc. (formerly known as Continental Airlines, Inc.), a Delaware corporation (the “Company”), as supplemented by Trust Supplement No. 2019-1AA-O thereto, dated as of February 11, 2019 (the “Trust Supplement” and, together

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with the Basic Agreement, the “Agreement”), between the Trustee and the Company, a summary of certain of the pertinent provisions of which is set forth below. To the extent not otherwise defined herein, the capitalized terms used herein have the meanings assigned to them in the Agreement. This Certificate is one of the duly authorized Certificates designated as “United Airlines Pass Through Certificates, Series 2019-1AA-O” (herein called the “Certificates”). This Certificate is issued under and is subject to the terms, provisions and conditions of the Agreement. By virtue of its acceptance hereof, the holder of this Certificate (the “Certificateholder” and, together with all other holders of Certificates issued by the Trust, the “Certificateholders”) assents to and agrees to be bound by the provisions of the Agreement and the Intercreditor Agreement. The property of the Trust includes certain Equipment Notes and all rights of the Trust to receive payments under the Intercreditor Agreement and the Liquidity Facility (the “Trust Property”). Each issue of the Equipment Notes is secured by, among other things, a security interest in an Aircraft owned by the Company.

The Certificates represent Fractional Undivided Interests in the Trust and the Trust Property and have no rights, benefits or interest in respect of any other separate trust established pursuant to the terms of the Basic Agreement for any other series of certificates issued pursuant thereto.

Subject to and in accordance with the terms of the Agreement and the Intercreditor Agreement, from funds then available to the Trustee, there will be distributed on February 25 and August 25 of each year (a “Regular Distribution Date”) commencing August 25, 2019, to the Person in whose name this Certificate is registered at the close of business on the 15th day preceding the Regular Distribution Date, an amount in respect of the Scheduled Payments on the Equipment Notes due on such Regular Distribution Date, the receipt of which has been confirmed by the Trustee, equal to the product of the percentage interest in the Trust evidenced by this Certificate and an amount equal to the sum of such Scheduled Payments. Subject to and in accordance with the terms of the Agreement and the Intercreditor Agreement, in the event that Special Payments on the Equipment Notes are received by the Trustee, from funds then available to the Trustee, there shall be distributed on the applicable Special Distribution Date, to the Person in whose name this Certificate is registered at the close of business on the 15th day preceding the Special Distribution Date, an amount in respect of such Special Payments on the Equipment Notes, the receipt of which has been confirmed by the Trustee, equal to the product of the percentage interest in the Trust evidenced by this Certificate and an amount equal to the sum of such Special Payments so received. If a Regular Distribution Date or Special Distribution Date is not a Business Day, distribution shall be made on the immediately following Business Day with the same force and effect as if made on such Regular Distribution Date or Special Distribution Date and no interest shall accrue during the intervening period. The Trustee shall mail notice of each Special Payment and the Special Distribution Date therefor to the Certificateholder of this Certificate.

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Distributions on this Certificate will be made by the Trustee by check mailed to the Person entitled thereto, without presentation or surrender of this Certificate or the making of any notation hereon, except that with respect to Certificates registered on the Record Date in the name of a Clearing Agency (or its nominee) such distribution shall be made by wire transfer. Except as otherwise provided in the Agreement and notwithstanding the above, the final distribution on this Certificate will be made after notice mailed by the Trustee of the pendency of such distribution and only upon presentation and surrender of this Certificate at the office or agency of the Trustee specified in such notice.

The Certificates do not represent a direct obligation of, or an obligation guaranteed by, or an interest in, the Company or the Trustee or any affiliate thereof. The Certificates are limited in right of payment, all as more specifically set forth on the face hereof and in the Agreement. All payments or distributions made to Certificateholders under the Agreement shall be made only from the Trust Property and only to the extent that the Trustee shall have sufficient income or proceeds from the Trust Property to make such payments in accordance with the terms of the Agreement. Each Certificateholder of this Certificate, by its acceptance hereof, agrees that it will look solely to the income and proceeds from the Trust Property to the extent available for distribution to such Certificateholder as provided in the Agreement. This Certificate does not purport to summarize the Agreement and reference is made to the Agreement for information with respect to the interests, rights, benefits, obligations, privileges, and duties evidenced hereby. A copy of the Agreement may be examined during normal business hours at the principal office of the Trustee, and at such other places, if any, designated by the Trustee, by any Certificateholder upon request.

The Agreement permits, with certain exceptions therein provided, the amendment thereof and the modification of the rights and obligations of the Company and the rights of the Certificateholders under the Agreement at any time by the Company and the Trustee with the consent of the Certificateholders holding Certificates evidencing Fractional Undivided Interests aggregating not less than a majority in interest in the Trust. Any such consent by the Certificateholder of this Certificate shall be conclusive and binding on such Certificateholder and upon all future Certificateholders of this Certificate and of any Certificate issued upon the transfer hereof or in exchange hereof or in lieu hereof whether or not notation of such consent is made upon this Certificate. The Agreement also permits the amendment thereof, in certain limited circumstances, without the consent of the Certificateholders of any of the Certificates.

As provided in the Agreement and subject to certain limitations set forth therein, the transfer of this Certificate is registrable in the Register upon surrender of this Certificate for registration of transfer at the offices or agencies maintained by the Trustee in its capacity as Registrar, or by any successor Registrar, duly endorsed or accompanied by a written instrument of transfer in form satisfactory to the Trustee and the Registrar, duly executed by the Certificateholder hereof or such Certificateholder’s attorney duly authorized in writing, and thereupon one or more new Certificates of authorized denominations evidencing the same aggregate Fractional Undivided Interest in the Trust will be issued to the designated transferee or transferees.

Under certain circumstances set forth in Section 7.01 of the Trust Supplement, all of the Trustee’s right, title and interest to the Trust Property may be assigned, transferred and delivered to the Related Trustee of the Related Trust pursuant to the Assignment and Assumption Agreement. Upon the effectiveness of such Assignment and Assumption Agreement (the “Transfer”), the Trust shall be terminated, the Certificateholders shall receive beneficial interests in the Related Trust in exchange for their interests in the Trust equal to their respective beneficial

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interests in the Trust, the Certificates representing Fractional Undivided Interests in the Trust shall be deemed for all purposes of the Agreement and the Related Pass Through Trust Agreement to be certificates representing the same Fractional Undivided Interests in the Related Trust and its trust property. Each Certificateholder, by its acceptance of this Certificate or a beneficial interest herein, agrees to be bound by the Assignment and Assumption Agreement and subject to the terms of the Related Pass Through Trust Agreement as a Certificateholder thereunder. From and after the Transfer, unless and to the extent the context otherwise requires, references herein to the Trust, the Agreement and the Trustee shall constitute references to the Related Trust, the Related Pass Through Trust Agreement and trustee of the Related Trust, respectively.

The Certificates are issuable only as registered Certificates without coupons in minimum denominations of $1,000 Fractional Undivided Interest and integral multiples thereof, except that one Certificate may be issued in a different denomination. As provided in the Agreement and subject to certain limitations therein set forth, the Certificates are exchangeable for new Certificates of authorized denominations evidencing the same aggregate Fractional Undivided Interest in the Trust, as requested by the Certificateholder surrendering the same.

No service charge will be made for any such registration of transfer or exchange, but the Trustee shall require payment of a sum sufficient to cover any tax or governmental charge payable in connection therewith.

Each Certificateholder and Investor, by its acceptance of this Certificate or a beneficial interest herein, agrees to treat the Trust as a grantor trust for all U.S. federal, state and local income tax purposes.

The Trustee, the Registrar, and any agent of the Trustee or the Registrar may treat the person in whose name this Certificate is registered as the owner hereof for all purposes, and neither the Trustee, the Registrar, nor any such agent shall be affected by any notice to the contrary.

The obligations and responsibilities created by the Agreement and the Trust created thereby shall terminate upon the distribution to Certificateholders of all amounts required to be distributed to them pursuant to the Agreement and the disposition of all property held as part of the Trust Property.

Any Person acquiring or accepting this Certificate or an interest herein will, by such acquisition or acceptance, be deemed to have represented and warranted to and for the benefit of the Company that either: (i) no assets of an employee benefit plan subject to Title I of the Employee Retirement Income Security Act of 1974, as amended (“ERISA”), a plan subject to Section 4975 of the Internal Revenue Code of 1986, as amended (the “Code”), or a governmental, church or foreign plan subject to a law that is similar to Title I of ERISA or Section 4975 of the Code (a “Similar Law Plan”) have been used to purchase or hold this Certificate or an interest herein or (ii) the purchase and holding of this Certificate or an interest herein either (a) in the case of assets of an employee benefit plan subject to Title I of ERISA or a plan subject to Section 4975 of the Code, are exempt from the prohibited transaction restrictions

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of ERISA and the Code pursuant to one or more prohibited transaction statutory or administrative exemptions or (b) in the case of assets of a Similar Law Plan, will not violate any similar state, local or foreign law.

If the purchaser or transferee of this Certificate or an interest herein is an employee benefit plan subject to Title I of ERISA or a plan subject to Section 4975 of the Code, it will be deemed to represent, warrant and agree that (i) none of United Continental Holdings, Inc., the Company, or the Underwriters, nor any of their affiliates, has provided any investment recommendation or investment advice on which it, or any fiduciary or other person investing the assets of such plan (“Plan Fiduciary”), has relied in connection with its decision to invest in this Certificate, and they are not otherwise acting as a fiduciary, as defined in Section 3(21) of ERISA or Section 4975(e)(3) of the Code, to such plan or the Plan Fiduciary in connection with such plan’s acquisition of this Certificate; and (ii) the Plan Fiduciary is exercising its own independent judgment in evaluating the transaction.

THE AGREEMENT AND, UNTIL THE TRANSFER, THIS CERTIFICATE SHALL BE GOVERNED BY AND CONSTRUED IN ACCORDANCE WITH THE LAWS OF THE STATE OF DELAWARE AND THE OBLIGATIONS, RIGHTS AND REMEDIES OF THE PARTIES HEREUNDER SHALL BE DETERMINED IN ACCORDANCE WITH SUCH LAWS. THE RELATED PASS THROUGH TRUST AGREEMENT AND, FROM AND AFTER THE TRANSFER, THIS CERTIFICATE SHALL BE GOVERNED AND CONSTRUED IN ACCORDANCE WITH THE LAWS OF THE STATE OF NEW YORK AND THE OBLIGATIONS, RIGHTS AND REMEDIES OF THE PARTIES HEREUNDER SHALL BE DETERMINED IN ACCORDANCE WITH SUCH LAWS.

Unless the certificate of authentication hereon has been executed by the Trustee, by manual signature, this Certificate shall not be entitled to any benefit under the Agreement or be valid for any purpose.

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IN WITNESS WHEREOF, the Trustee has caused this Certificate to be duly executed.

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FORM OF THE TRUSTEE’S CERTIFICATE OF AUTHENTICATION

This is one of the Certificates referred to in the within-mentioned Agreement.

EXHIBIT B

[DTC Letter of Representations]

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EXHIBIT C

FORM OF ASSIGNMENT AND ASSUMPTION AGREEMENT

United Airlines Pass Through Trust 2019-1AA-O

ASSIGNMENT AND ASSUMPTION AGREEMENT (2019-1AA-O), dated ________ __, ____ (the “Assignment Agreement”), between Wilmington Trust, National Association, a national banking association (“WTNA”), not in its individual capacity except as expressly provided herein, but solely as trustee under the Pass Through Trust Agreement dated as of October 3, 2012 (as amended or modified from time to time, the “Basic Agreement”), as supplemented by the Trust Supplement No. 2019-1AA-O, dated as of February 11, 2019 (the “Trust Supplement” and together with the Basic Agreement, the “Agreement”) in respect of the United Airlines Pass Through Trust 2019-1AA-O (the “Assignor”), and Wilmington Trust, National Association, a national banking association, not in its individual capacity except as expressly provided herein, but solely as trustee under the Basic Agreement, as supplemented by the Trust Supplement No. 2019-1AA-S, dated as of February 11, 2019 (the “New Supplement”, and, together with the Basic Agreement, the “New Agreement”) in respect of the United Airlines Pass Through Trust 2019-1AA-S (the “Assignee”).

W I T N E S S E T H:

WHEREAS, the parties hereto desire to effect on the date hereof (the “Transfer Date”) (a) the transfer by the Assignor to the Assignee of all of the right, title and interest of the Assignor in, under and with respect to, among other things, the Trust Property and each of the documents listed in Schedule I hereto (the “Scheduled Documents”) and (b) the assumption by the Assignee of the obligations of the Assignor (i) under the Scheduled Documents and (ii) in respect of the Applicable Certificates issued under the Agreement; and

WHEREAS, the Scheduled Documents permit such transfer upon satisfaction of certain conditions heretofore or concurrently herewith being complied with;

NOW, THEREFORE, in consideration of the premises and of the mutual covenants and agreements herein contained, the parties hereto do hereby agree as follows (capitalized terms used herein without definition having the meaning ascribed thereto in the Agreement):

1.    Assignment. The Assignor does hereby sell, assign, convey, transfer and set over unto the Assignee as of the Transfer Date all of its present and future right, title and interest in, under and with respect to the Trust Property and the Scheduled Documents and each other contract, agreement, document or instrument relating to the Trust Property or the Scheduled Documents (such other contracts, agreements, documents or instruments, together with the Scheduled Documents, to be referred to as the “Assigned Documents”), and any proceeds therefrom, together with all documents and instruments evidencing any of such right, title and interest.

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2.    Assumption. The Assignee hereby assumes for the benefit of the Assignor and each of the parties listed in Schedule II hereto (collectively, the “Beneficiaries”) all of the duties and obligations of the Assignor, whenever accrued, pursuant to the Assigned Documents and hereby confirms that it shall be deemed a party to each of the Assigned Documents to which the Assignor is a party and shall be bound by all the terms thereof (including the agreements and obligations of the Assignor set forth therein) as if therein named as the Assignor. Further, the Assignee hereby assumes for the benefit of the Assignor and the Beneficiaries all of the duties and obligations of the Assignor under the Outstanding Applicable Certificates and hereby confirms that the Applicable Certificates representing Fractional Undivided Interests under the Agreement shall be deemed for all purposes of the Agreement and the New Agreement to be certificates representing the same Fractional Undivided Interests under the New Agreement equal to their respective beneficial interests in the trust created under the Agreement.

3.    Effectiveness. This Assignment Agreement shall be effective upon the execution and delivery hereof by the parties hereto, and each Applicable Certificateholder, by its acceptance of its Applicable Certificate or a beneficial interest therein, agrees to be bound by the terms of this Assignment Agreement.

4.    Payments. The Assignor hereby covenants and agrees to pay over to the Assignee, if and when received following the Transfer Date, any amounts (including any sums payable as interest in respect thereof) paid to or for the benefit of the Assignor that, under Section 1 hereof, belong to the Assignee.

5.    Further Assurances. The Assignor shall, at any time and from time to time, upon the request of the Assignee, promptly and duly execute and deliver any and all such further instruments and documents and take such further action as the Assignee may reasonably request to obtain the full benefits of this Assignment Agreement and of the rights and powers herein granted. The Assignor agrees to deliver any Applicable Certificates, and all Trust Property, if any, then in the physical possession of the Assignor, to the Assignee.

6.    Representations and Warranties. (a) The Assignee represents and warrants to the Assignor and each of the Beneficiaries that:

(i)    it has all requisite power and authority and legal right to enter into and carry out the transactions contemplated hereby and to carry out and perform the obligations of the “Pass Through Trustee” under the Assigned Documents;

(ii)    on and as of the date hereof, the representations and warranties of the Assignee set forth in Section 7.15 of the Basic Agreement and Section 5.04 of the New Supplement are true and correct.

(b)    The Assignor represents and warrants to the Assignee that:

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(i)    it is duly incorporated, validly existing and in good standing under the laws of the United States and has the full trust power, authority and legal right under the laws of the United States and of the state of the United States in which it is located pertaining to its trust and fiduciary powers to execute and deliver this Assignment Agreement;

(ii)    the execution and delivery by it of this Assignment Agreement and the performance by it of its obligations hereunder have been duly authorized by it and will not violate its articles of association or by-laws or the provisions of any indenture, mortgage, contract or other agreement to which it is a party or by which it is bound; and

(iii)    this Assignment Agreement constitutes the legal, valid and binding obligations of it enforceable against it in accordance with its terms, except as the same may be limited by applicable bankruptcy, insolvency, reorganization, moratorium or similar laws affecting the rights of creditors generally and by general principles of equity, whether considered in a proceeding at law or in equity.

7.    GOVERNING LAW. THIS ASSIGNMENT AGREEMENT SHALL BE GOVERNED BY AND CONSTRUED IN ACCORDANCE WITH THE LAWS OF THE STATE OF NEW YORK INCLUDING MATTERS OF CONSTRUCTION, VALIDITY AND PERFORMANCE.

8.    Counterparts. This Assignment Agreement may be executed in any number of counterparts, all of which together shall constitute a single instrument. It shall not be necessary that any counterpart be signed by both parties so long as each party shall sign at least one counterpart.

9.    Third Party Beneficiaries. The Assignee hereby agrees, for the benefit of the Beneficiaries, that its representations, warranties and covenants contained herein are also intended to be for the benefit of each Beneficiary, and each Beneficiary shall be deemed to be an express third party beneficiary with respect thereto, entitled to enforce directly and in its own name any rights or claims it may have against such party as such beneficiary.

10.     Notice.    Promptly following the Transfer Date, the Assignee shall notify the Depositary of the occurrence of the assignment hereunder and the name and contact information of the Assignee.

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IN WITNESS WHEREOF, the parties hereto, through their respective officers thereunto duly authorized, have duly executed this Assignment Agreement as of the day and year first above written.

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Schedule I

Schedule of Assigned Documents

(1) Intercreditor Agreement dated as of February 11, 2019 among the Trustee, the Other Trustees party thereto, the Liquidity Provider and the Subordination Agent.

(2) Escrow and Paying Agent Agreement (Class AA) dated as of February 11, 2019 among the Escrow Agent, the Underwriters, the Trustee and the Escrow Paying Agent.

(3) Note Purchase Agreement dated as of February 11, 2019 among the Company, the Trustee, the Other Trustees party thereto, the Subordination Agent, the Escrow Agent and the Escrow Paying Agent.

(4) Deposit Agreement (Class AA) dated as of February 11, 2019 between the Escrow Agent and the Depositary.

(5) Each of the Operative Agreements (as defined in the Participation Agreement for each Aircraft) in effect as of the Transfer Date.

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Schedule II

Schedule of Beneficiaries

Wilmington Trust, National Association, not in its individual capacity but solely as Subordination Agent

Wilmington Trust, National Association, not in its individual capacity but solely as Paying Agent

National Australia Bank Limited, acting through its New York Branch, as Liquidity Provider

Sumitomo Mitsui Banking Corporation, acting through its New York Branch, as Depositary

United Airlines, Inc.

Citigroup Global Markets Inc., as Underwriter

Credit Suisse Securities (USA) LLC, as Underwriter

Goldman Sachs & Co. LLC, as Underwriter

Deutsche Bank Securities Inc., as Underwriter

Morgan Stanley & Co. LLC, as Underwriter

J.P. Morgan Securities LLC, as Underwriter

Barclays Capital Inc., as Underwriter

Merrill Lynch, Pierce, Fenner & Smith Incorporated, as Underwriter

BBVA Securities Inc., as Underwriter

BNP Paribas Securities Corp., as Underwriter

Credit Agricole Securities (USA) Inc., as Underwriter

Standard Chartered Bank, as Underwriter

Wells Fargo Securities, LLC., as Underwriter

U.S. Bank National Association, as Escrow Agent

Each of the other parties to the Assigned Documents

EXHIBIT 4.2

EXECUTION VERSION

TRUST SUPPLEMENT No. 2019-1AA-S

Dated as of February 11, 2019

between

WILMINGTON TRUST, NATIONAL ASSOCIATION

as Trustee,

and

UNITED AIRLINES, INC.

to

PASS THROUGH TRUST AGREEMENT

Dated as of October 3, 2012

$716,625,000

United Airlines Pass Through Trust 2019-1AA-S

4.15% United Airlines Pass Through Certificates, Series 2019-1AA-S

TABLE OF CONTENTS

Page

This Trust Supplement No. 2019-1AA-S, dated as of February 11, 2019 (herein called the “Trust Supplement”), between United Airlines, Inc., a Delaware corporation (the “Company”), and Wilmington Trust, National Association (the “Trustee”), to the Pass Through Trust Agreement, dated as of October 3, 2012, between the Company (formerly known as Continental Airlines, Inc.) and the Trustee (the “Basic Agreement”).

W I T N E S S E T H:

WHEREAS, the Basic Agreement, unlimited as to the aggregate face amount of Certificates (unless otherwise specified herein, capitalized terms used herein without definition having the respective meanings specified in the Basic Agreement) which may be issued thereunder, has heretofore been executed and delivered;

WHEREAS, the Company is the owner of or has obtained commitments from Boeing for the delivery of nine Boeing 737 MAX 9 aircraft, six Boeing 787-10 aircraft and ten Embraer ERJ 175 LL aircraft (collectively, the “Applicable Aircraft”);

WHEREAS, as of the Transfer Date, the Company will have financed the Applicable Aircraft;

WHEREAS, as of the Transfer Date, with respect to each Applicable Aircraft, the Company will have issued pursuant to an Indenture, on a recourse basis, Equipment Notes to finance a portion of the purchase price of such Applicable Aircraft;

WHEREAS, as of the Transfer Date, the Related Trustee will assign, transfer and deliver all of such trustee’s right, title and interest to the trust property held by the Related Trustee to the Trustee pursuant to the Assignment and Assumption Agreement;

WHEREAS, the Trustee, effective only, but automatically, upon execution and delivery of the Assignment and Assumption Agreement, will be deemed to have declared the creation of the United Airlines Pass Through Trust 2019-1AA-S (the “Applicable Trust”) for the benefit of the Applicable Certificateholders, and each Holder of Applicable Certificates “Outstanding” as of the Transfer Date, as the grantors of the Applicable Trust, by their respective acceptances of such Applicable Certificates (as defined below), will join in the creation of the Applicable Trust with the Trustee;

WHEREAS, all Applicable Certificates to be deemed issued by the Applicable Trust will evidence Fractional Undivided Interests in the Applicable Trust and will convey no rights, benefits or interests in respect of any property other than the Trust Property except for those Applicable Certificates to which an Escrow Receipt (as defined below) has been affixed;

WHEREAS, upon the execution and delivery of the Assignment and Assumption Agreement, all of the conditions and requirements necessary to make this Trust Supplement, when duly executed and delivered, a valid, binding and legal instrument in accordance with its terms and for the purposes herein expressed, have been done, performed and fulfilled, and the execution and delivery of this Trust Supplement in the form and with the terms hereof have been in all respects duly authorized; and

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WHEREAS, this Trust Supplement is subject to the provisions of the Trust Indenture Act of 1939, as amended, and shall, to the extent applicable, be governed by such provisions.

NOW THEREFORE, in consideration of the premises herein, it is agreed between the Company and the Trustee as follows:

ARTICLE I

THE CERTIFICATES

Section 1.01. The Certificates. The “Applicable Certificates” shall be known as “United Airlines Pass Through Certificates, Series 2019-1AA-S”. Each Applicable Certificate represents a Fractional Undivided Interest in the Applicable Trust created hereby. The Applicable Certificates shall be the only instruments evidencing a Fractional Undivided Interest in the Applicable Trust.

The terms and conditions applicable to the Applicable Certificates are as follows:

(a)    The aggregate face amount of the Applicable Certificates that shall be initially deemed issued under the Agreement shall be equal to the aggregate principal amount of “Outstanding” pass through certificates representing Fractional Undivided Interests in the Related Trust on the Transfer Date. Subject to the preceding sentence and Section 5.01 of this Trust Supplement and except for Applicable Certificates authenticated and delivered under Sections 3.03, 3.04, 3.05 and 3.06 of the Basic Agreement, no Applicable Certificates shall be authenticated under the Agreement.

(b)    The Regular Distribution Dates with respect to any distribution of Scheduled Payments means February 25 and August 25 of each year, commencing on August 25, 2019 until distribution of all of the Scheduled Payments to be made under the Equipment Notes has been made.

(c)    The Special Distribution Dates with respect to the Applicable Certificates means any Business Day on which a Special Payment is to be distributed pursuant to the Agreement.

(d)    At the Escrow Agent’s request under the Escrow Agreement, the Trustee shall affix the corresponding Escrow Receipt to each Applicable Certificate. In any event, any transfer or exchange of any Applicable Certificate shall also effect a transfer or exchange of the related Escrow Receipt. Prior to the Final Distribution, no transfer or exchange of any Applicable Certificate shall be permitted unless the corresponding Escrow Receipt is attached thereto and also is so transferred or exchanged. By acceptance of any Applicable Certificate to which an Escrow Receipt is attached, each Holder of such an Applicable Certificate acknowledges and accepts the restrictions on transfer of the Escrow Receipt set forth herein and in the Escrow Agreement.

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(e)    (i)    The Applicable Certificates shall be in the form attached as Exhibit A to the Related Pass Through Trust Supplement, with such appropriate insertions, omissions, substitutions and other variations as are required or permitted by the Related Pass Through Trust Agreement or the Agreement, as the case may be, or as the Trustee may deem appropriate, to reflect the fact that the Applicable Certificates are being issued under the Agreement as opposed to under the Related Pass Through Trust Agreement. Any Person acquiring or accepting an Applicable Certificate or an interest therein will, by such acquisition or acceptance, be deemed to have represented and warranted to and for the benefit of the Company that either (x) no assets of an employee benefit plan subject to Title I of the Employee Retirement Income Security Act of 1974, as amended (“ERISA”), a plan subject to Section 4975 of the Internal Revenue Code of 1986, as amended (the “Code”), or a governmental, church or foreign plan subject to a law that is similar to Title I of ERISA or Section 4975 of the Code (a “Similar Law Plan”) have been used to purchase or hold such Applicable Certificate or an interest therein or (y) the purchase and holding of such Applicable Certificate or an interest therein either (A) in the case of assets of an employee benefit plan subject to Title I of ERISA or a plan subject to Section 4975 of the Code, are exempt from the prohibited transaction restrictions of ERISA and the Code pursuant to one or more prohibited transaction statutory or administrative exemptions or (B ) in the case of assets of a Similar Law Plan, will not violate any similar state, local or foreign law.

(ii)    The Applicable Certificates shall be Book-Entry Certificates and shall be subject to the conditions set forth in the Letter of Representations between the Applicable Trust and the Clearing Agency attached as Exhibit B to the Related Pass Through Trust Supplement.

(f)    If the purchaser or transferee of an Applicable Certificate or an interest therein is an employee benefit plan subject to Title I of ERISA or a plan subject to Section 4975 of the Code, it will be deemed to represent, warrant and agree that (i) none of United Continental Holdings, Inc., the Company, or the Underwriters, nor any of their affiliates, has provided any investment recommendation or investment advice on which it, or any fiduciary or other person investing the assets of such plan (“Plan Fiduciary”), has relied in connection with its decision to invest in the Applicable Certificates, and they are not otherwise acting as a fiduciary, as defined in Section 3(21) of ERISA or Section 4975(e)(3) of the Code, to such plan or the Plan Fiduciary in connection with such plan’s acquisition of the Applicable Certificates; and (ii) the Plan Fiduciary is exercising its own independent judgment in evaluating the transaction.

(g)    The “Participation Agreements” as defined in this Trust Supplement are the “Note Purchase Agreements” referred to in the Basic Agreement.

(h)    The Applicable Certificates are subject to the Intercreditor Agreement, the Deposit Agreement and the Escrow Agreement.

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(i)    The Applicable Certificates are entitled to the benefits of the Liquidity Facility.

(j)    The Responsible Party is the Company.

(k)    The date referred to in clause (i) of the definition of the term “PTC Event of Default” in the Basic Agreement is the Final Maturity Date.

(l)    The “particular sections of the Note Purchase Agreement”, for purposes of clause (3) of Section 7.07 of the Basic Agreement, are Section 8.1 of each Participation Agreement.

(m)    The Equipment Notes to be acquired and held in the Applicable Trust, and the related Aircraft and Note Documents, are described in the NPA.

ARTICLE II

DEFINITIONS

Section 2.01. Definitions. For all purposes of the Basic Agreement as supplemented by this Trust Supplement, the following capitalized terms have the following meanings (any term used herein which is defined in both this Trust Supplement and the Basic Agreement shall have the meaning assigned thereto in this Trust Supplement for purposes of the Basic Agreement as supplemented by this Trust Supplement):

Agreement: Means the Basic Agreement, as supplemented by this Trust Supplement.

Aircraft: Means each of the Applicable Aircraft (or Substitute Aircraft) in respect of which a Participation Agreement is to be or is entered into in accordance with the NPA (or any Substitute Aircraft, including engines therefor, owned by the Company and securing one or more Equipment Notes).

Aircraft Purchase Agreement: Has the meaning specified in the NPA.

Applicable Aircraft: Has the meaning specified in the recitals hereto.

Applicable Certificate: Means any of the “Applicable Certificates” issued by the Related Trust and that are “Outstanding” (as defined in the Related Pass Through Trust Agreement) as of the Transfer Date (the “Transfer Date Certificates”) and any Certificate issued in exchange therefor or replacement thereof pursuant to the Agreement.

Applicable Certificateholder: Means the Person in whose name an Applicable Certificate is registered on the Register for the Applicable Certificates.

Applicable Trust: Has the meaning specified in the recitals hereto.

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Assignment and Assumption Agreement: Means the assignment and assumption agreement substantially in the form of Exhibit C to the Related Pass Through Trust Supplement executed and delivered in accordance with Section 7.01 of the Related Pass Through Trust Supplement.

Basic Agreement: Has the meaning specified in the first paragraph of this Trust Supplement.

Boeing: Means The Boeing Company.

Business Day: Means any day other than a Saturday, a Sunday or a day on which commercial banks are required or authorized to close in New York, New York, Chicago, Illinois, or, so long as any Applicable Certificate is Outstanding, the city and state in which the Trustee, the Subordination Agent or any Loan Trustee maintains its Corporate Trust Office or receives and disburses funds.

Certificate: Has the meaning specified in the Intercreditor Agreement.

Certificate Buyout Event: Means that a United Bankruptcy Event has occurred and is continuing and either of the following events has occurred: (A) both (i) the 60-day period specified in Section 1110(a)(2)(A) of the U.S. Bankruptcy Code (the “60-Day Period”) has expired and (ii) the Company has not entered into one or more agreements under Section 1110(a)(2)(A) of the U.S. Bankruptcy Code to perform all of its obligations under all of the Indentures or, if it has entered into such agreements, has at any time thereafter failed to cure any default under any of the Indentures in accordance with Section 1110(a)(2)(B) of the U.S. Bankruptcy Code; or (B) prior to the expiry of the 60-Day Period, the Company shall have abandoned any Aircraft.

Class: Has the meaning specified in the Intercreditor Agreement.

Closing Notice: Has the meaning specified in the NPA.

Company: Has the meaning specified in the first paragraph of this Trust Supplement.

Controlling Party: Has the meaning specified in the Intercreditor Agreement.

Cut-off Date: Means the earlier of (a) the Delivery Period Termination Date and (b) the date on which a Triggering Event occurs.

Delivery Period Termination Date: Has the meaning specified in the Related Pass Through Trust Supplement.

Deposit Agreement: Means the Deposit Agreement dated as of February 11, 2019 relating to the Applicable Certificates between the Depositary and the Escrow Agent, as the same may be amended, supplemented or otherwise modified from time to time in accordance with its terms.

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Depositary: Means Sumitomo Mitsui Banking Corporation, acting through its New York Branch.

Deposits: Has the meaning specified in the Deposit Agreement.

Distribution Date: Means any Regular Distribution Date or Special Distribution Date as the context requires.

ERISA: Has the meaning specified in Section 1.01(e) of this Trust Supplement.

Escrow Agent: Means, initially, U.S. Bank National Association and any replacement or successor therefor appointed in accordance with the Escrow Agreement.

Escrow Agreement: Means the Escrow and Paying Agent Agreement dated as of February 11, 2019 relating to the Applicable Certificates, among the Escrow Agent, the Escrow Paying Agent, the Related Trustee (and after the Transfer Date, the Trustee) and the Underwriters, as the same may be amended, supplemented or otherwise modified from time to time in accordance with its terms.

Escrow Paying Agent: Means the Person acting as paying agent under the Escrow Agreement.

Escrow Receipt: Means the receipt substantially in the form annexed to the Escrow Agreement representing a Fractional Undivided Interest in the funds held in escrow thereunder.

Final Distribution: Has the meaning specified in the Escrow Agreement.

Final Maturity Date: Means February 25, 2033.

Final Withdrawal: Has the meaning specified in the Escrow Agreement.

Final Withdrawal Date: Has the meaning specified in the Escrow Agreement.

Indenture: Means each of the separate trust indentures and mortgages relating to the Aircraft, each as specified or described in a Closing Notice delivered pursuant to the NPA or the related Participation Agreement, in each case as the same may be amended, supplemented or otherwise modified from time to time in accordance with its terms.

Intercreditor Agreement: Means the Intercreditor Agreement dated as of February 11, 2019 among the Related Trustee (and after the Transfer Date, the Trustee), the Related Other Trustees (and after the Transfer Date, the Other Trustees) party thereto, the Liquidity Provider, the liquidity provider relating to the Class A Certificates and Wilmington Trust, National Association, as Subordination Agent and as trustee thereunder, as amended, supplemented or otherwise modified from time to time in accordance with its terms.

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Investors: Means the Underwriters, together with all subsequent beneficial owners of the Applicable Certificates.

Liquidity Facility: Means, initially, the Revolving Credit Agreement dated as of February 11, 2019 relating to the Applicable Certificates, between the Liquidity Provider and Wilmington Trust, National Association, as Subordination Agent, as agent and trustee for the Applicable Trust, and, from and after the replacement of such agreement pursuant to the Intercreditor Agreement, the replacement liquidity facility therefor, in each case as amended, supplemented or otherwise modified from time to time in accordance with their respective terms.

Liquidity Provider: Means, initially, National Australia Bank Limited, acting through its New York Branch, and any replacements or successors therefor appointed in accordance with the Intercreditor Agreement.

Make-Whole Amount: Has the meaning specified in any Indenture.

Note Documents: Means the Equipment Notes with respect to the Applicable Certificates and, with respect to any such Equipment Note, the Indenture and the Participation Agreement relating to such Equipment Note.

NPA: Means the Note Purchase Agreement, dated as of the date hereof among the Related Trustee (and after the Transfer Date, the Trustee), the Related Other Trustees (and after the Transfer Date, the Other Trustees) party thereto, the Company, the Escrow Agent, the Escrow Paying Agent and the Subordination Agent, providing for, among other things, the purchase of Equipment Notes by the Trustee on behalf of the Applicable Trust, as the same may be amended, supplemented or otherwise modified from time to time, in accordance with its terms.

Other Agreements: Means (i) the Basic Agreement, as supplemented by Trust Supplement No. 2019-1A-S dated as of the date hereof relating to United Airlines Pass Through Trust 2019-1A-S, (ii) the Basic Agreement as supplemented by a Trust Supplement relating to any Additional Trust and (iii) the Basic Agreement as supplemented by a Trust Supplement relating to any Refinancing Trust.

Other Trustees: Means the trustees under the Other Agreements, and any successor or other trustee appointed as provided therein.

Other Trusts: Means the United Airlines Pass Through Trust 2019-1A-S, an Additional Trust or Trusts, if any, and a Refinancing Trust or Trusts, if any, created by the Other Agreements.

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Outstanding: When used with respect to Applicable Certificates, means, as of the date of determination, all Transfer Date Certificates, and all other Applicable Certificates theretofore authenticated and delivered under the Agreement, in each case except:

(i)    Applicable Certificates theretofore canceled by the Registrar or delivered to the Trustee or the Registrar for cancellation;

(ii)    Applicable Certificates for which money in the full amount required to make the final distribution with respect to such Applicable Certificates pursuant to Section 11.01 of the Basic Agreement has been theretofore deposited with the Trustee in trust for the Applicable Certificateholders as provided in Section 4.01 of the Basic Agreement pending distribution of such money to such Applicable Certificateholders pursuant to payment of such final distribution; and

(iii)    Applicable Certificates in exchange for or in lieu of which other Applicable Certificates have been authenticated and delivered pursuant to the Agreement.

Participation Agreement: Means each Participation Agreement entered into by the Related Trustee pursuant to the NPA, as the same may be amended, supplemented or otherwise modified in accordance with its terms.

Pool Balance: Means, as of any date, (i) the original aggregate face amount of the Applicable Certificates, less (ii) the aggregate amount of all payments made as of such date in respect of such Certificates, the Applicable Certificates or the Deposits, other than payments made in respect of interest or premium (including Make-Whole Amount) thereon or reimbursement of any costs or expenses incurred in connection therewith. The Pool Balance as of any date shall be computed after giving effect to any special distribution with respect to unused Deposits, payment of principal of the Equipment Notes, or payment with respect to other Trust Property and the distribution thereof to be made on that date.

Pool Factor: Means, as of any Distribution Date, the quotient (rounded to the seventh decimal place) computed by dividing (i) the Pool Balance by (ii) the original aggregate face amount of the Applicable Certificates. The Pool Factor as of any Distribution Date shall be computed after giving effect to any special distribution with respect to unused Deposits, payment of principal of the Equipment Notes, or payment with respect to other Trust Property and the distribution thereof to be made on that date.

Prospectus Supplement: Means the final Prospectus Supplement dated January 28, 2019 relating to the offering of the Applicable Certificates and the Class A Certificates.

Ratings Confirmation: Has the meaning specified in the Intercreditor Agreement.

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Related Other Pass Through Trust Agreements: Means the “Other Agreements” as defined in the Related Pass Through Trust Agreement.

Related Other Trustees: Means the “Other Trustees” as defined in the Related Pass Through Trust Agreement.

Related Other Trusts: Means the “Other Trusts” as defined in the Related Pass Through Trust Agreement.

Related Pass Through Trust Agreement: Means the Basic Agreement as supplemented by the Related Pass Through Trust Supplement.

Related Pass Through Trust Supplement: Means the Trust Supplement No. 2019-1AA-O dated as of the date hereof, relating to the United Airlines Pass Through Trust 2019-1AA-O and entered into by the Company and the Related Trustee, as amended, supplemented or otherwise modified from time to time in accordance with its terms.

Related Trust: Means the United Airlines Pass Through Trust 2019-1AA-O, formed under the Related Pass Through Trust Agreement.

Related Trustee: Means the trustee under the Related Pass Through Trust Agreement.

Scheduled Payment: Means, with respect to any Equipment Note, (i) any payment of principal or interest on such Equipment Note (other than any such payment which is not in fact received by the Trustee or the Subordination Agent within five days of the date on which such payment is scheduled to be made) or (ii) any payment of interest on the Applicable Certificates with funds drawn under the Liquidity Facility, which payment in any such case represents the installment of principal on such Equipment Note at the stated maturity of such installment, the payment of regularly scheduled interest accrued on the unpaid principal amount of such Equipment Note, or both; provided, however, that any payment of principal, premium (including Make-Whole Amount), if any, or interest resulting from the redemption or purchase of any Equipment Note shall not constitute a Scheduled Payment.

Special Payment: Means any payment (other than a Scheduled Payment) in respect of, or any proceeds of, any Equipment Note or Collateral (as defined in each Indenture).

Substitute Aircraft: Has the meaning specified in the NPA.

Transfer Date: Means the moment of execution and delivery of the Assignment and Assumption Agreement by each of the parties thereto.

Transfer Date Certificates: Has the meaning specified in the definition of Applicable Certificates.

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Triggering Event: Has the meaning assigned to such term in the Intercreditor Agreement.

Trust Property: Means (i) subject to the Intercreditor Agreement, the Equipment Notes held as the property of the Applicable Trust, all monies at any time paid thereon or in respect thereof and all monies due and to become due thereunder, (ii) funds from time to time deposited in the Certificate Account and the Special Payments Account and, subject to the Intercreditor Agreement, any proceeds from the sale by the Trustee pursuant to Article VI of the Basic Agreement of any Equipment Note and (iii) all rights of the Applicable Trust and the Trustee, on behalf of the Applicable Trust, under the Intercreditor Agreement, the Escrow Agreement, the NPA and the Liquidity Facility, including, without limitation, all rights to receive certain payments thereunder, and all monies paid to the Trustee on behalf of the Applicable Trust pursuant to the Intercreditor Agreement or the Liquidity Facility, provided that rights with respect to the Deposits or under the Escrow Agreement will not constitute Trust Property.

Trust Supplement: Has the meaning specified in the first paragraph of this trust supplement.

Trustee: Has the meaning specified in the first paragraph of this Trust Supplement.

Underwriters: Means, collectively, Citigroup Global Markets Inc., Credit Suisse Securities (USA) LLC, Goldman Sachs & Co. LLC, Deutsche Bank Securities Inc., Morgan Stanley & Co. LLC, J.P. Morgan Securities LLC, Barclays Capital Inc., Merrill Lynch, Pierce, Fenner & Smith Incorporated, BBVA Securities Inc., BNP Paribas Securities Corp., Credit Agricole Securities (USA) Inc., Standard Chartered Bank and Wells Fargo Securities, LLC.

Underwriting Agreement: Means the Underwriting Agreement related to the Applicable Certificates dated January 28, 2019 among Citigroup Global Markets Inc. and Credit Suisse Securities (USA) LLC, as representatives of the several Underwriters, the Company and the Depositary, as the same may be amended, supplemented or otherwise modified from time to time in accordance with its terms.

United Bankruptcy Event: Has the meaning specified in the Intercreditor Agreement.

ARTICLE III

DISTRIBUTIONS; STATEMENTS TO CERTIFICATEHOLDERS

Section 3.01. Statements to Applicable Certificateholders. (a) On each Distribution Date, the Trustee will include with each distribution to Applicable Certificateholders of a Scheduled Payment or Special Payment, as the case may be, a statement setting forth the information provided below (in the case of a Special Payment, reflecting in part the information provided by the Escrow Paying Agent under the Escrow Agreement). Such statement shall set forth (per $1,000 face amount Applicable Certificate as to (ii), (iii), (iv) and (v) below) the following information:

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(i)    The aggregate amount of funds distributed on such Distribution Date under the Agreement and under the Escrow Agreement, indicating the amount allocable to each source, including any portion thereof paid by the Liquidity Provider;

(ii)    The amount of such distribution under the Agreement allocable to principal and the amount allocable to premium (including Make-Whole Amount), if any;

(iii)    The amount of such distribution under the Agreement allocable to interest;

(iv)    The amount of such distribution under the Escrow Agreement allocable to interest;

(v)    The amount of such distribution under the Escrow Agreement allocable to unused Deposits, if any; and

(vi)    The Pool Balance and the Pool Factor.

With respect to the Applicable Certificates registered in the name of a Clearing Agency or its nominee, on the Record Date prior to each Distribution Date, the Trustee will request that such Clearing Agency post on its Internet bulletin board a securities position listing setting forth the names of all Clearing Agency Participants reflected on such Clearing Agency’s books as holding interests in the Applicable Certificates on such Record Date. On each Distribution Date, the Trustee will mail to each such Clearing Agency Participant the statement described above and will make available additional copies as requested by such Clearing Agency Participant for forwarding to holders of interests in the Applicable Certificates.

(b)    Within a reasonable period of time after the end of each calendar year but not later than the latest date permitted by law, the Trustee shall furnish to each Person who at any time during such calendar year was an Applicable Certificateholder of record a statement containing the sum of the amounts determined pursuant to clauses (a)(i), (a)(ii), (a)(iii), (a)(iv) and (a)(v) above for such calendar year or, in the event such Person was an Applicable Certificateholder of record during a portion of such calendar year, for such portion of such year, and such other items as are readily available to the Trustee and which an Applicable Certificateholder shall reasonably request as necessary for the purpose of such Applicable Certificateholder’s preparation of its U.S. federal income tax returns. Such statement and such other items shall be prepared on the basis of information supplied to the Trustee by the Clearing Agency Participants and shall be delivered by the Trustee to such Clearing Agency Participants to be available for forwarding by such Clearing Agency Participants to the holders of interests in the Applicable Certificates in the manner described in Section 3.01(a) of this Trust Supplement.

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(c)    If the aggregate principal payments scheduled for a Regular Distribution Date prior to the Delivery Period Termination Date differ from the amount thereof set forth for the Applicable Certificates on page S-39 of the Prospectus Supplement, by no later than the 15th day prior to such Regular Distribution Date, the Trustee (if the Related Trustee has not already done so) shall mail written notice of the actual amount of such scheduled payments to the Applicable Certificateholders of record as of a date within 15 Business Days prior to the date of mailing. If the Trustee has given such notice, the Company shall not give a “Closing Notice” (as defined in the NPA) under the NPA providing for a “Funding Date” (as defined in the NPA) on or after the date the Trustee gives such notice and on or prior to such Regular Distribution Date and shall revoke any Closing Notice previously given that provides for such a Funding Date.

(d)    Promptly following (i) the Delivery Period Termination Date, if there has been any change in the information set forth in clauses (y) and (z) below from that set forth on page S-39 of the Prospectus Supplement, and (ii) the date of any early redemption of, or any default in the payment of principal or interest in respect of, any of the Equipment Notes held in the Applicable Trust, or any Final Withdrawal, the Trustee (if the Related Trustee has not already done so) shall furnish to Applicable Certificateholders of record on such date a statement setting forth (x) the expected Pool Balances for each subsequent Regular Distribution Date following the Delivery Period Termination Date, (y) the related Pool Factors for such Regular Distribution Dates and (z) the expected principal payment schedule of the Equipment Notes, in the aggregate, held as Trust Property at the date of such notice. With respect to the Applicable Certificates registered in the name of a Clearing Agency, on the Transfer Date, the Trustee (if the Related Trustee has not already done so) will request from such Clearing Agency a securities position listing setting forth the names of all Clearing Agency Participants reflected on such Clearing Agency’s books as holding interests in the Applicable Certificates on the Delivery Period Termination Date. The Trustee (if the Related Trustee has not already done so) will mail to each such Clearing Agency Participant the statement described above and will make available additional copies as requested by such Clearing Agency Participant for forwarding to holders of interests in the Applicable Certificates.

(e)    The Trustee shall provide promptly to the Applicable Certificateholders all material non-confidential information received by the Trustee from the Company.

(f)     This Section 3.01 supersedes and replaces Section 4.03 of the Basic Agreement, with respect to the Applicable Trust.

Section 3.02. Special Payments Account. (a) The Trustee shall establish and maintain on behalf of the Applicable Certificateholders a Special Payments Account as one or more accounts, which shall be non-interest bearing except as provided in Section 4.04 of the Basic Agreement. The Trustee shall hold the Special Payments Account in trust for the benefit of the Applicable Certificateholders and shall make or permit withdrawals therefrom only as provided in the Agreement. On each day when one or more Special Payments are made to the Trustee under the Intercreditor Agreement, the Trustee, upon receipt thereof, shall immediately deposit the aggregate amount of such Special Payments in the Special Payments Account.

(b)    This Section 3.02 supersedes and replaces Section 4.01(b) of the Basic Agreement in its entirety, with respect to the Applicable Trust.

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Section 3.03. Distributions from Special Payments Account. (a) On each Special Distribution Date with respect to any Special Payment or as soon thereafter as the Trustee has confirmed receipt of any Special Payments due on the Equipment Notes held (subject to the Intercreditor Agreement) in the Applicable Trust or realized upon the sale of such Equipment Notes, the Trustee shall distribute out of the Special Payments Account the entire amount of such Special Payment deposited therein pursuant to Section 3.02(a) of this Trust Supplement. There shall be so distributed to each Applicable Certificateholder of record on the Record Date with respect to such Special Distribution Date (other than as provided in Section 7.01 of this Trust Supplement concerning the final distribution) by check mailed to such Applicable Certificateholder, at the address appearing in the Register, such Applicable Certificateholder’s pro rata share (based on the Fractional Undivided Interest in the Applicable Trust held by such Applicable Certificateholder) of the total amount in the Special Payments Account on account of such Special Payment, except that, with respect to Applicable Certificates registered on the Record Date in the name of a Clearing Agency (or its nominee), such distribution shall be made by wire transfer in immediately available funds to the account designated by such Clearing Agency (or such nominee).

(b)    The Trustee shall, at the expense of the Company, cause notice of each Special Payment to be mailed to each Applicable Certificateholder at his address as it appears in the Register. In the event of redemption or purchase of Equipment Notes held in the Applicable Trust, such notice shall be mailed not less than 15 days prior to the Special Distribution Date for the Special Payment resulting from such redemption or purchase, which Special Distribution Date shall be the date of such redemption or purchase. In the case of any other Special Payments, such notice shall be mailed as soon as practicable after the Trustee has confirmed that it has received funds for such Special Payment, stating the Special Distribution Date for such Special Payment which shall occur not less than 15 days after the date of such notice and as soon as practicable thereafter. Notices with respect to a Special Payment mailed by the Trustee shall set forth:

(i)    The Special Distribution Date and the Record Date therefor (except as otherwise provided in Section 7.01 of this Trust Supplement),

(ii)    The amount of the Special Payment for each $1,000 face amount Applicable Certificate and the amount thereof constituting principal, premium (including Make-Whole Amount), if any, and interest,

(iii)    The reason for the Special Payment, and

(iv)    If the Special Distribution Date is the same date as a Regular Distribution Date, the total amount to be received on such date for each $1,000 face amount Applicable Certificate.

If the amount of premium (including Make-Whole Amount), if any, payable upon the redemption or purchase of an Equipment Note has not been calculated at the time that the Trustee mails notice of a Special Payment, it shall be sufficient if the notice sets forth the other amounts to be distributed and states that any premium (including Make-Whole Amount) received will also be distributed.

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If any redemption of the Equipment Notes held in the Applicable Trust is canceled, the Trustee, as soon as possible after learning thereof, shall cause notice thereof to be mailed to each Applicable Certificateholder at its address as it appears on the Register.

(c)     This Section 3.03 supersedes and replaces Section 4.02(b) and Section 4.02(c) of the Basic Agreement in their entirety, with respect to the Applicable Trust.

Section 3.04. Limitation of Liability for Payments. Section 3.09 of the Basic Agreement shall be amended, with respect to the Applicable Trust, by deleting the phrase “the Owner Trustees or the Owner Participants” in the second sentence thereof and adding in lieu thereof “the Liquidity Provider”.

ARTICLE IV

DEFAULT

Section 4.01. Purchase Rights of Certificateholders. (a) By acceptance of its Applicable Certificate, each Applicable Certificateholder agrees that at any time after the occurrence and during the continuation of a Certificate Buyout Event:

(i)    So long as no Additional Certificateholder has elected to exercise its rights to purchase Certificates pursuant to, and given notice of such election in accordance with, this Section 4.01(a) (upon such election and notification thereof, the right specified in this Section 4.01(a)(i) shall be suspended and (x) upon consummation of such purchase pursuant to such election, be terminated with respect to such Certificate Buyout Event, or (y) upon failure to consummate such purchase on the proposed purchase date, such right shall be reinstated), each Class A Certificateholder (other than the Company or any of its Affiliates) shall have the right to purchase, for the purchase price set forth in the Class A Trust Agreement, all, but not less than all, of the Applicable Certificates upon 15 days’ written notice to the Trustee and each other Class A Certificateholder, on the third Business Day next following the expiry of such 15-day notice period, provided that (A) if prior to the end of such 15-day period any other Class A Certificateholder (other than the Company or any of its Affiliates) notifies such purchasing Class A Certificateholder that such other Class A Certificateholder wants to participate in such purchase, then such other Class A Certificateholder (other than the Company or any of its Affiliates) may join with the purchasing Class A Certificateholder to purchase all, but not less than all, of the Applicable Certificates pro rata based on the Fractional Undivided Interest in the Class A Trust held by each such Class A Certificateholder and (B) if prior to the end of such 15-day period any other Class A Certificateholder fails to notify the purchasing Class A Certificateholder of such other Class A Certificateholder’s desire to participate in such a purchase, then such other Class A Certificateholder shall lose its right to purchase the Applicable Certificates pursuant to this Section 4.01(a)(i);

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(ii)    If any Additional Certificates are issued pursuant to one or more Additional Trusts, each Additional Certificateholder (other than the Company or any of its Affiliates) shall have the right (which shall not expire upon any purchase of the Applicable Certificates pursuant to clause (i) above) to purchase all, but not less than all, of the Applicable Certificates, the Class A Certificates and any Additional Certificates ranked senior to the Additional Certificates held by the purchasing Additional Certificateholders upon 15 days’ written notice to the Trustee, the Class A Trustee, any Additional Trustee with respect to Additional Certificates that rank senior to the Additional Certificates held by the purchasing Additional Certificateholders and each other Additional Certificateholder of the same class, on the third Business Day next following the expiry of such 15-day notice period, provided that (A) if prior to the end of such 15-day period any other Additional Certificateholder of such class (other than the Company or any of its Affiliates) notifies such purchasing Additional Certificateholder that such other Additional Certificateholder wants to participate in such purchase, then such other Additional Certificateholder (other than the Company or any of its Affiliates) may join with the purchasing Additional Certificateholder to purchase all, but not less than all, of the Applicable Certificates, the Class A Certificates and such senior Additional Certificates pro rata based on the Fractional Undivided Interest in the applicable Additional Trust held by each such Additional Certificateholder and (B) if prior to the end of such 15-day period any other Additional Certificateholder of such class fails to notify the purchasing Additional Certificateholder of such other Additional Certificateholder’s desire to participate in such a purchase, then such other Additional Certificateholder shall lose its right to purchase the Applicable Certificates, the Class A Certificates and such senior Additional Certificates pursuant to this Section 4.01(a)(ii); and

(iii)    If any Refinancing Certificates are issued, each Refinancing Certificateholder shall have the same right (subject to the same terms and conditions) to purchase Certificates pursuant to this Section 4.01(a) (and to receive notice in connection therewith) as the Certificateholders of the Class that such Refinancing Certificates refinanced.

The purchase price with respect to the Applicable Certificates shall be equal to the Pool Balance of the Applicable Certificates, together with accrued and unpaid interest thereon to the date of such purchase, without premium (including Make-Whole Amount), but including any other amounts then due and payable to the Applicable Certificateholders under the Agreement, the Intercreditor Agreement, the Escrow Agreement or any Note Document or on or in respect of the Applicable Certificates; provided, however, that no such purchase of Applicable Certificates shall be effective unless the purchaser(s) shall certify to the Trustee that contemporaneously with such purchase, such purchaser(s) is (are) purchasing, pursuant to the terms of the Agreement and the Other Agreements, all of the Applicable Certificates, the Class A Certificates (unless such purchaser is a Class A Certificateholder) and, if applicable, the Additional Certificates that rank senior to the Additional Certificates held by the purchasing Additional Certificateholder(s). Each payment of the purchase price of the Applicable Certificates referred to in the first sentence hereof shall be made to an account or accounts designated by the Trustee and each such purchase shall be subject to the terms of this Section 4.01. Each Applicable Certificateholder agrees by its acceptance of its Applicable Certificate that (at any time after the occurrence of a Certificate Buyout Event) it will, upon payment from such Class A Certificateholder(s), Additional Certificateholder(s) or Refinancing Certificateholder(s), as the case may be, of the purchase price set forth in the first sentence of this paragraph, (i) forthwith sell, assign, transfer and convey to

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the purchaser(s) thereof (without recourse, representation or warranty of any kind except for its own acts), all of the right, title, interest and obligation of such Applicable Certificateholder in the Agreement, the Escrow Agreement, the Deposit Agreement, the Intercreditor Agreement, the Liquidity Facility, the NPA, the Note Documents and all Applicable Certificates and Escrow Receipts held by such Applicable Certificateholder (excluding all right, title and interest under any of the foregoing to the extent such right, title or interest is with respect to an obligation not then due and payable as respects any action or inaction or state of affairs occurring prior to such sale) (and the purchaser shall assume all of such Applicable Certificateholder’s obligations under the Agreement, the Escrow Agreement, the Deposit Agreement, the Intercreditor Agreement, the Liquidity Facility, the NPA, the Note Documents and all such Applicable Certificates and Escrow Receipts), (ii) if such purchase occurs after a record date specified in Section 2.03 of the Escrow Agreement relating to the distribution of unused Deposits and/or accrued and unpaid interest on Deposits and prior to or on the related distribution date thereunder, forthwith turn over to the purchaser(s) of its Applicable Certificate all amounts, if any, received by it on account of such distribution, and (iii) if such purchase occurs after a Record Date relating to any distribution and prior to or on the related Distribution Date, forthwith turn over to the purchaser(s) of its Applicable Certificate all amounts, if any, received by it on account of such distribution. The Applicable Certificates will be deemed to be purchased on the date payment of the purchase price is made notwithstanding the failure of the Applicable Certificateholders to deliver any Applicable Certificates and, upon such a purchase, (I) the only rights of the Applicable Certificateholders will be to deliver the Applicable Certificates to the purchaser(s) and receive the purchase price for such Applicable Certificates and (II) if the purchaser(s) shall so request, such Applicable Certificateholder will comply with all the provisions of Section 3.04 of the Basic Agreement to enable new Applicable Certificates to be issued to the purchaser in such denominations as it shall request. All charges and expenses in connection with the issuance of any such new Applicable Certificates shall be borne by the purchaser thereof.

As used in this Section 4.01 and elsewhere in this Trust Supplement, the terms “Additional Certificate”, “Additional Certificateholder”, “Additional Equipment Notes”, “Additional Trust”, “Class A Certificate”, “Class A Certificateholder”, “Class A Trust”, “Class A Trust Agreement”, “Class A Trustee”, “Refinancing Certificates”, “Refinancing Certificateholder”, “Refinancing Equipment Notes” and “Refinancing Trust” shall have the respective meanings assigned to such terms in the Intercreditor Agreement.

(b)    This Section 4.01 supersedes and replaces Section 6.01(b) of the Basic Agreement, with respect to the Applicable Trust.

Section 4.02. Amendment of Section 6.05 of the Basic Agreement. Section 6.05 of the Basic Agreement shall be amended, with respect to the Applicable Trust, by deleting the phrase “and thereby annul any Direction given by such Certificateholders or the Trustee to such Loan Trustee with respect thereto,” set forth in the first sentence thereof.

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ARTICLE V

THE TRUSTEE

Section 5.01. Acquisition of Trust Property. (a) The Trustee is hereby irrevocably authorized and directed to execute and deliver the Assignment and Assumption Agreement on the date specified in Section 7.01 of the Related Pass Through Trust Supplement, subject only to the satisfaction of the conditions set forth in said Section 7.01. The Agreement (except only for this sentence and the immediately preceding sentence hereof, which are effective upon execution and delivery hereof) shall become effective upon the execution and delivery of the Assignment and Assumption Agreement by the Trustee and the Related Trustee, automatically and without any further signature or action on the part of the Company and the Trustee, and shall thereupon constitute the legal, valid and binding obligation of the parties hereto enforceable against each of the parties hereto in accordance with its terms. Upon such execution and delivery of the Assignment and Assumption Agreement, the Related Trust shall be terminated, the Applicable Certificateholders shall receive beneficial interests in the Applicable Trust in exchange for their interests in the Related Trust equal to their respective beneficial interests in the Related Trust and the “Outstanding” (as defined in the Related Pass Through Trust Agreement) pass through certificates representing Fractional Undivided Interests in the Related Trust shall be deemed for all purposes of the Agreement, without further signature or action of any party or Certificateholder, to be Certificates representing the same Fractional Undivided Interests in the Applicable Trust and Trust Property. By acceptance of its Applicable Certificate, each Applicable Certificateholder consents to and ratifies such assignment, transfer and delivery of the trust property of the Related Trust to the Trustee upon the execution and delivery of the Assignment and Assumption Agreement. The provisions of this Section 5.01(a) supersede and replace the provisions of Section 2.02 of the Basic Agreement with respect to the Applicable Trust, and all provisions of the Basic Agreement relating to Postponed Notes or Section 2.02 of the Basic Agreement shall not apply to the Applicable Trust.

(b)    The Trustee, upon the execution and delivery of the Assignment and Assumption Agreement, acknowledges its acceptance of all right, title and interest in and to the Trust Property and declares that the Trustee holds and will hold such right, title and interest for the benefit of all then present and future Applicable Certificateholders, upon the trusts herein and in the Basic Agreement set forth. By the acceptance of each Applicable Certificate issued to it under the Related Pass Through Trust Agreement and deemed issued under the Agreement, each Holder of any such Applicable Certificate as grantor of the Applicable Trust thereby joins in the creation and declaration of the Applicable Trust. The provisions of this Section 5.01(b) supersede and replace the provisions of Section 2.03 of the Basic Agreement, with respect to the Applicable Trust.

Section 5.02. [Intentionally Omitted].

Section 5.03. The Trustee. (a) Subject to Section 5.04 of this Trust Supplement and Section 7.15 of the Basic Agreement, the Trustee shall not be responsible in any manner whatsoever for or in respect of the validity or sufficiency of this Trust Supplement, the Deposit Agreement, the NPA or the Escrow Agreement or the due execution hereof or thereof by the Company or the other parties thereto (other than the Trustee), or for or in respect of the recitals and statements contained herein or therein, all of which recitals and statements are made solely by the Company, except that the Trustee hereby represents and warrants that each of this Trust Supplement, the Basic Agreement, each Applicable Certificate, the Intercreditor Agreement, the NPA and the Escrow Agreement has been executed and delivered by one of its officers who is duly authorized to execute and deliver such document on its behalf.

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(b)    Except as herein otherwise provided and except during the continuation of an Event of Default in respect of the Applicable Trust created hereby, no duties, responsibilities or liabilities are assumed, or shall be construed to be assumed, by the Trustee by reason of this Trust Supplement other than as set forth in the Agreement, and this Trust Supplement is executed and accepted on behalf of the Trustee, subject to all the terms and conditions set forth in the Agreement, as fully to all intents as if the same were herein set forth at length.

Section 5.04. Representations and Warranties of the Trustee. The Trustee hereby represents and warrants that, on the Transfer Date:

(a)    The Trustee has full power, authority and legal right to receive the Trust Property assigned by the Related Trustee, assume the obligations under, and perform, the Assignment and Assumption Agreement, this Trust Supplement, the Intercreditor Agreement, the Escrow Agreement, the NPA and the Note Documents to which it is a party and has taken all necessary action to authorize such receipt, assumption and performance by it of this Trust Supplement, the Intercreditor Agreement, the Escrow Agreement, the NPA and the Note Documents to which it is or is to become a party;

(b)    The receipt of the Trust Property under the Assignment and Assumption Agreement and the performance by the Trustee of the Assignment and Assumption Agreement, this Trust Supplement, the Intercreditor Agreement, the Escrow Agreement, the NPA and the Note Documents to which it is or is to become a party (i) will not violate any provision of any United States federal law or the law of the state of the United States where it is located governing the banking and trust powers of the Trustee or any order, writ, judgment, or decree of any court, arbitrator or governmental authority applicable to the Trustee or any of its assets, (ii) will not violate any provision of the articles of association or by-laws of the Trustee, and (iii) will not violate any provision of, or constitute, with or without notice or lapse of time, a default under, or result in the creation or imposition of any lien on any properties included in the Trust Property pursuant to the provisions of any mortgage, indenture, contract, agreement or other undertaking to which it is a party, which violation, default or lien could reasonably be expected to have an adverse effect on the Trustee’s performance or ability to perform its duties hereunder or thereunder or on the transactions contemplated herein or therein;

(c)    The receipt of the Trust Property under the Assignment and Assumption Agreement and the performance by the Trustee of the Assignment and Assumption Agreement, this Trust Supplement, the Intercreditor Agreement, the Escrow Agreement, the NPA and the Note Documents to which it is or is to become a party will not require the authorization, consent, or approval of, the giving of notice to, the filing or registration with, or the taking of any other action in respect of, any governmental authority or agency of the United States or the state of the United States where it is located regulating the banking and corporate trust activities of the Trustee; and

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(d)    The Assignment and Assumption Agreement has been duly executed and delivered by the Trustee and this Trust Supplement, the Intercreditor Agreement, the Escrow Agreement, the NPA and the Note Documents to which it is or is to become a party have been, or will be, as applicable, duly executed and delivered by the Trustee and constitute, or will constitute, as applicable, the legal, valid and binding agreements of the Trustee, enforceable against it in accordance with their respective terms; provided, however, that enforceability may be limited by (i) applicable bankruptcy, insolvency, reorganization, moratorium or similar laws affecting the rights of creditors generally and (ii) general principles of equity.

Section 5.05. Trustee Liens. The Trustee in its individual capacity agrees, in addition to the agreements contained in Section 7.17 of the Basic Agreement, that it will at its own cost and expense promptly take any action as may be necessary to duly discharge and satisfy in full any Trustee’s Liens on or with respect to the Trust Property which is attributable to the Trustee in its individual capacity and which is unrelated to the transactions contemplated by the Intercreditor Agreement or the NPA.

ARTICLE VI

ADDITIONAL AMENDMENT; SUPPLEMENTAL AGREEMENTS

Section 6.01. Amendment of Section 5.02 of the Basic Agreement. Section 5.02 of the Basic Agreement shall be amended, with respect to the Applicable Trust, by (i) replacing the phrase “of the Note Documents and of this Agreement” set forth in paragraph (b) thereof with the phrase “of the Note Documents, of the NPA and of this Agreement” and (ii) replacing the phrase “of this Agreement and any Note Document” set forth in the last paragraph of Section 5.02 with the phrase “of this Agreement, the NPA and any Note Document”.

Section 6.02. Supplemental Agreements without Consent of Applicable Certificateholders. Without limitation of Section 9.01 of the Basic Agreement, under the terms of, and subject to the limitations contained in, Section 9.01 of the Basic Agreement, the Company may (but will not be required to), and the Trustee (subject to Section 9.03 of the Basic Agreement) shall, at the Company’s request, at any time and from time to time:

(i)    Enter into one or more agreements supplemental to the Escrow Agreement, the NPA or the Deposit Agreement for any of the purposes set forth in clauses (1) through (9) of such Section 9.01, and (without limitation of the foregoing or Section 9.01 of the Basic Agreement) (a) clauses (2) and (3) of such Section 9.01 shall also be deemed to include the Company’s obligations under (in the case of clause (2)), and the Company’s rights and powers conferred by (in the case of clause (3)), the NPA, and (b) references in clauses (4), (6) and (7) of such Section 9.01 to “any Intercreditor Agreement or any Liquidity Facility” shall also be deemed to refer to “the Intercreditor Agreement, the Liquidity Facility, the Escrow Agreement, the NPA or the Deposit Agreement”,

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(ii)    Enter into one or more agreements supplemental to the Agreement, the Intercreditor Agreement or the NPA to provide for the formation of one or more Additional Trusts, the issuance of Additional Certificates, the purchase by an Additional Trust (if any) of applicable Additional Equipment Notes and other matters incidental thereto or otherwise contemplated by Section 2.01(b) of the Basic Agreement, subject to the provisions of Section 4(a)(vi) of the NPA and Section 9.1(d) of the Intercreditor Agreement, and

(iii)     Enter into one or more agreements supplemental to the Agreement to provide for the formation of one or more Refinancing Trusts, the issuance of Refinancing Certificates, the purchase by any Refinancing Trust of applicable Refinancing Equipment Notes and other matters incidental thereto or as otherwise contemplated by Section 2.01(b) of the Basic Agreement, subject to the provisions of Section 4(a)(vi) of the NPA and Section 9.1(c) of the Intercreditor Agreement.

Section 6.03. Supplemental Agreements with Consent of Applicable Certificateholders. Without limitation of Section 9.02 of the Basic Agreement, the provisions of Section 9.02 of the Basic Agreement shall apply to agreements or amendments for the purpose of adding any provisions to or changing in any manner or eliminating any of the provisions of the Escrow Agreement, the Deposit Agreement, the Liquidity Facility or the NPA or modifying in any manner the rights and obligations of the Applicable Certificateholders under the Escrow Agreement, the Deposit Agreement, the Liquidity Facility or the NPA; provided that the provisions of Section 9.02(1) of the Basic Agreement shall be deemed to include reductions in any manner of, or delay in the timing of, any receipt by the Applicable Certificateholders of payments upon the Deposits.

Section 6.04. Consent of Holders of Certificates Issued under Other Trusts. Notwithstanding any provision in Section 6.02 or Section 6.03 of this Trust Supplement to the contrary, no amendment or modification of Section 4.01 of this Trust Supplement shall be effective unless the trustee for each Class of Certificates affected by such amendment or modification shall have consented thereto.

ARTICLE VII

TERMINATION OF TRUST

Section 7.01. Termination of the Applicable Trust. (a) The respective obligations and responsibilities of the Company and the Trustee with respect to the Applicable Trust shall terminate upon the distribution to all Applicable Certificateholders and the Trustee of all amounts required to be distributed to them pursuant to the Agreement and the disposition of all property held as part of the Trust Property; provided, however, that in no event shall the Applicable Trust continue beyond one hundred ten (110) years following the date of the execution of this Trust Supplement.

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Notice of any termination, specifying the Distribution Date upon which the Applicable Certificateholders may surrender their Applicable Certificates to the Trustee for payment of the final distribution and cancellation, shall be mailed promptly by the Trustee to Applicable Certificateholders not earlier than the 60th day and not later than the 15th day next preceding such final Distribution Date specifying (A) the Distribution Date upon which the proposed final payment of the Applicable Certificates will be made upon presentation and surrender of Applicable Certificates at the office or agency of the Trustee therein specified, (B) the amount of any such proposed final payment, and (C) that the Record Date otherwise applicable to such Distribution Date is not applicable, payments being made only upon presentation and surrender of the Applicable Certificates at the office or agency of the Trustee therein specified. The Trustee shall give such notice to the Registrar at the time such notice is given to Applicable Certificateholders. Upon presentation and surrender of the Applicable Certificates in accordance with such notice, the Trustee shall cause to be distributed to Applicable Certificateholders such final payments.

In the event that all of the Applicable Certificateholders shall not surrender their Applicable Certificates for cancellation within six months after the date specified in the above-mentioned written notice, the Trustee shall give a second written notice to the remaining Applicable Certificateholders to surrender their Applicable Certificates for cancellation and receive the final distribution with respect thereto. No additional interest shall accrue on the Applicable Certificates after the Distribution Date specified in the first written notice. In the event that any money held by the Trustee for the payment of distributions on the Applicable Certificates shall remain unclaimed for two years (or such lesser time as the Trustee shall be satisfied, after sixty days’ notice from the Company, is one month prior to the escheat period provided under applicable law) after the final distribution date with respect thereto, the Trustee shall pay to each Loan Trustee the appropriate amount of money relating to such Loan Trustee and shall give written notice thereof to the Company.

(b)     The provisions of this Section 7.01 supersede and replace the provisions of Section 11.01 of the Basic Agreement in its entirety, with respect to the Applicable Trust.

ARTICLE VIII

MISCELLANEOUS PROVISIONS

Section 8.01. Basic Agreement Ratified. Except and so far as herein expressly provided, all of the provisions, terms and conditions of the Basic Agreement are in all respects ratified and confirmed; and the Basic Agreement and this Trust Supplement shall be taken, read and construed as one and the same instrument. All replacements of provisions of, and other modifications of the Basic Agreement set forth in this Trust Supplement are solely with respect to the Applicable Trust.

Section 8.02. GOVERNING LAW. THE AGREEMENT AND THE APPLICABLE CERTIFICATES SHALL BE GOVERNED BY AND CONSTRUED IN ACCORDANCE WITH THE LAWS OF THE STATE OF NEW YORK. THIS SECTION 8.02 SUPERSEDES AND REPLACES SECTION 12.05 OF THE BASIC AGREEMENT, WITH RESPECT TO THE APPLICABLE TRUST.

Section 8.03. Execution in Counterparts. This Trust Supplement may be executed in any number of counterparts, each of which shall be an original, but such counterparts shall together constitute but one and the same instrument.

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Section 8.04. Intention of Parties. The parties hereto intend that the Applicable Trust be classified for U.S. federal income tax purposes as a grantor trust under Subpart E, Part I of Subchapter J of the Internal Revenue Code of 1986, as amended, and not as a trust or association taxable as a corporation or as a partnership. Each Applicable Certificateholder and Investor, by its acceptance of its Applicable Certificate or a beneficial interest therein, agrees to treat the Applicable Trust as a grantor trust for all U.S. federal, state and local income tax purposes. The powers granted and obligations undertaken pursuant to the Agreement shall be so construed so as to further such intent.

IN WITNESS WHEREOF, the Company and the Trustee have caused this Trust Supplement to be duly executed by their respective officers thereto duly authorized, as of the day and year first written above.

Signature Page to Class AA-S Trust Supplement 19-1

Exhibit 4.3

EXECUTION VERSION

TRUST SUPPLEMENT No. 2019-1A-O

Dated as of February 11, 2019

between

WILMINGTON TRUST, NATIONAL ASSOCIATION

as Trustee,

and

UNITED AIRLINES, INC.

to

PASS THROUGH TRUST AGREEMENT

Dated as of October 3, 2012

$296,445,000

United Airlines Pass Through Trust 2019-1A-O

4.55% United Airlines Pass Through Certificates, Series 2019-1A-O

TABLE OF CONTENTS

Page

Exhibit A    -    Form of Certificate

Exhibit B    -    DTC Letter of Representations

Exhibit C    -    Form of Assignment and Assumption Agreement

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This Trust Supplement No. 2019-1A-O, dated as of February 11, 2019 (herein called the “Trust Supplement”), between United Airlines, Inc., a Delaware corporation (the “Company”), and Wilmington Trust, National Association (the “Trustee”), to the Pass Through Trust Agreement, dated as of October 3, 2012, between the Company (formerly known as Continental Airlines, Inc.) and the Trustee (the “Basic Agreement”).

W I T N E S S E T H:

WHEREAS, the Basic Agreement, unlimited as to the aggregate face amount of Certificates (unless otherwise specified herein, capitalized terms used herein without definition having the respective meanings specified in the Basic Agreement) which may be issued thereunder, has heretofore been executed and delivered;

WHEREAS, the Company is the owner of or has obtained commitments from Boeing for the delivery of nine Boeing 737 MAX 9 aircraft, six Boeing 787-10 aircraft and ten Embraer ERJ 175 LL aircraft (collectively, the “Applicable Aircraft”);

WHEREAS, the Company intends to finance each of the Applicable Aircraft;

WHEREAS, with respect to each Applicable Aircraft, the Company will issue pursuant to an Indenture, on a recourse basis, Equipment Notes to finance a portion of the purchase price of such Applicable Aircraft;

WHEREAS, the Trustee hereby declares the creation of the United Airlines Pass Through Trust 2019-1A-O (the “Applicable Trust”) for the benefit of the Applicable Certificateholders, and the initial Applicable Certificateholders as the grantors of the Applicable Trust, by their respective acceptances of the Applicable Certificates (as defined below), join in the creation of the Applicable Trust with the Trustee;

WHEREAS, all Certificates to be issued by the Applicable Trust will evidence Fractional Undivided Interests in the Applicable Trust and will convey no rights, benefits or interests in respect of any property other than the Trust Property except for those Certificates to which an Escrow Receipt (as defined below) has been affixed;

WHEREAS, the Escrow Agent and the Underwriters have contemporaneously herewith entered into an Escrow Agreement with the Escrow Paying Agent pursuant to which the Underwriters have delivered to the Escrow Agent the proceeds from the sale of the Applicable Certificates, and have irrevocably instructed the Escrow Agent to withdraw and pay funds from such proceeds upon request and proper certification by the Trustee to purchase Equipment Notes as the conditions set forth in the NPA for such purchase are satisfied from time to time prior to the Delivery Period Termination Date;

WHEREAS, the Escrow Agent on behalf of the Applicable Certificateholders has contemporaneously herewith entered into a Deposit Agreement with the Depositary under which the Deposits referred to therein will be made and from which it will withdraw funds to allow the Trustee to purchase Equipment Notes from time to time prior to the Delivery Period Termination Date;

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WHEREAS, pursuant to the terms and conditions of the Basic Agreement as supplemented by this Trust Supplement (the “Agreement”) and the NPA, upon the financing of an Applicable Aircraft under the NPA, the Trustee on behalf of the Applicable Trust, using funds withdrawn under the Escrow Agreement, shall purchase one or more Equipment Notes having the same interest rate as, and final maturity date not later than the final Regular Distribution Date of, the Applicable Certificates issued hereunder and shall hold such Equipment Notes in trust for the benefit of the Applicable Certificateholders;

WHEREAS, all of the conditions and requirements necessary to make this Trust Supplement, when duly executed and delivered, a valid, binding and legal instrument in accordance with its terms and for the purposes herein expressed, have been done, performed and fulfilled, and the execution and delivery of this Trust Supplement in the form and with the terms hereof have been in all respects duly authorized; and

WHEREAS, this Trust Supplement is subject to the provisions of the Trust Indenture Act of 1939, as amended, and shall, to the extent applicable, be governed by such provisions.

NOW THEREFORE, in consideration of the premises herein, it is agreed between the Company and the Trustee as follows:

ARTICLE I

THE CERTIFICATES

Section 1.01. The Certificates. There is hereby created a series of Certificates to be issued under the Agreement to be distinguished and known as “United Airlines Pass Through Certificates, Series 2019-1A-O” (hereinafter defined as the “Applicable Certificates”). Each Applicable Certificate represents a Fractional Undivided Interest in the Applicable Trust created hereby. The Applicable Certificates shall be the only instruments evidencing a Fractional Undivided Interest in the Applicable Trust.

The terms and conditions applicable to the Applicable Certificates are as follows:

(a)    The aggregate face amount of the Applicable Certificates that shall be authenticated under the Agreement (except for Applicable Certificates authenticated and delivered under Sections 3.03, 3.04, 3.05 and 3.06 of the Basic Agreement) is $296,445,000.

(b)    The Regular Distribution Dates with respect to any distribution of Scheduled Payments means February 25 and August 25 of each year, commencing on August 25, 2019 until distribution of all of the Scheduled Payments to be made under the Equipment Notes has been made.

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(c)    The Special Distribution Dates with respect to the Applicable Certificates means any Business Day on which a Special Payment is to be distributed pursuant to the Agreement.

(d)    At the Escrow Agent’s request under the Escrow Agreement, the Trustee shall affix the corresponding Escrow Receipt to each Applicable Certificate. In any event, any transfer or exchange of any Applicable Certificate shall also effect a transfer or exchange of the related Escrow Receipt. Prior to the Final Distribution, no transfer or exchange of any Applicable Certificate shall be permitted unless the corresponding Escrow Receipt is attached thereto and also is so transferred or exchanged. By acceptance of any Applicable Certificate to which an Escrow Receipt is attached, each Holder of such an Applicable Certificate acknowledges and accepts the restrictions on transfer of the Escrow Receipt set forth herein and in the Escrow Agreement.

(e)    (i) The Applicable Certificates shall be in the form attached hereto as Exhibit A. Any Person acquiring or accepting an Applicable Certificate or an interest therein will, by such acquisition or acceptance, be deemed to have represented and warranted to and for the benefit of the Company that either (x) no assets of an employee benefit plan subject to Title I of the Employee Retirement Income Security Act of 1974, as amended (“ERISA”), a plan subject to Section 4975 of the Internal Revenue Code of 1986, as amended (the “Code”), or a governmental, church or foreign plan subject to a law that is similar to Title I of ERISA or Section 4975 of the Code (a “Similar Law Plan”) have been used to purchase or hold such Applicable Certificate or an interest therein or (y) the purchase and holding of such Applicable Certificate or an interest therein either (A) in the case of assets of an employee benefit plan subject to Title I of ERISA or a plan subject to Section 4975 of the Code, are exempt from the prohibited transaction restrictions of ERISA and the Code pursuant to one or more prohibited transaction statutory or administrative exemptions or (B) in the case of assets of a Similar Law Plan, will not violate any similar state, local or foreign law.

(ii)    The Applicable Certificates shall be Book-Entry Certificates and shall be subject to the conditions set forth in the Letter of Representations between the Applicable Trust and the Clearing Agency attached as Exhibit B.

(f)    If the purchaser or transferee of an Applicable Certificate or an interest therein is an employee benefit plan subject to Title I of ERISA or a plan subject to Section 4975 of the Code, it will be deemed to represent, warrant and agree that (i) none of United Continental Holdings, Inc., the Company, or the Underwriters, nor any of their affiliates, has provided any investment recommendation or investment advice on which it, or any fiduciary or other person investing the assets of such plan (“Plan Fiduciary”), has relied in connection with its decision to invest in the Applicable Certificates, and they are not otherwise acting as a fiduciary, as defined in Section 3(21) of ERISA or Section 4975(e)(3) of the Code, to such plan or the Plan Fiduciary in connection with such plan’s acquisition of the Applicable Certificates; and (ii) the Plan Fiduciary is exercising its own independent judgment in evaluating the transaction.

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(g)    The “Participation Agreements” as defined in this Trust Supplement are the “Note Purchase Agreements” referred to in the Basic Agreement.

(h)    The Applicable Certificates are subject to the Intercreditor Agreement, the Deposit Agreement and the Escrow Agreement.

(i)    The Applicable Certificates are entitled to the benefits of the Liquidity Facility.

(j)    The Responsible Party is the Company.

(k)    The date referred to in clause (i) of the definition of the term “PTC Event of Default” in the Basic Agreement is the Final Maturity Date.

(l)    The “particular sections of the Note Purchase Agreement”, for purposes of clause (3) of Section 7.07 of the Basic Agreement, are Section 8.1 of each Participation Agreement.

(m)    The Equipment Notes to be acquired and held in the Applicable Trust, and the related Aircraft and Note Documents, are described in the NPA.

ARTICLE II

DEFINITIONS

Section 2.01. Definitions. For all purposes of the Basic Agreement as supplemented by this Trust Supplement, the following capitalized terms have the following meanings (any term used herein which is defined in both this Trust Supplement and the Basic Agreement shall have the meaning assigned thereto in this Trust Supplement for purposes of the Basic Agreement as supplemented by this Trust Supplement):

Agreement: Has the meaning specified in the recitals hereto.

Aircraft: Means each of the Applicable Aircraft (or Substitute Aircraft) in respect of which a Participation Agreement is to be or is, as the case may be, entered into in accordance with the NPA (or any Substitute Aircraft, including engines therefor, owned by the Company and securing one or more Equipment Notes).

Aircraft Purchase Agreement: Has the meaning specified in the NPA.

Applicable Aircraft: Has the meaning specified in the recitals hereto.

Applicable Certificate: Has the meaning specified in Section 1.01 of this Trust Supplement.

Applicable Certificateholder: Means the Person in whose name an Applicable Certificate is registered on the Register for the Applicable Certificates.

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Applicable Closing Date: Has the meaning specified in Section 5.01(b) of this Trust Supplement.

Applicable Participation Agreement: Has the meaning specified in Section 5.01(b) of this Trust Supplement.

Applicable Trust: Has the meaning specified in the recitals hereto.

Assignment and Assumption Agreement: Means the assignment and assumption agreement substantially in the form of Exhibit C hereto executed and delivered in accordance with Section 7.01 of this Trust Supplement.

Basic Agreement: Has the meaning specified in the first paragraph of this Trust Supplement.

Boeing: Means The Boeing Company.

Business Day: Means any day other than a Saturday, a Sunday or a day on which commercial banks are required or authorized to close in New York, New York, Chicago, Illinois, or, so long as any Applicable Certificate is Outstanding, the city and state in which the Trustee, the Subordination Agent or any Loan Trustee maintains its Corporate Trust Office or receives and disburses funds.

Certificate: Has the meaning specified in the Intercreditor Agreement.

Certificate Buyout Event: Means that a United Bankruptcy Event has occurred and is continuing and either of the following events has occurred: (A) both (i) the 60-day period specified in Section 1110(a)(2)(A) of the U.S. Bankruptcy Code (the “60-Day Period”) has expired and (ii) the Company has not entered into one or more agreements under Section 1110(a)(2)(A) of the U.S. Bankruptcy Code to perform all of its obligations under all of the Indentures or, if it has entered into such agreements, has at any time thereafter failed to cure any default under any of the Indentures in accordance with Section 1110(a)(2)(B) of the U.S. Bankruptcy Code; or (B) prior to the expiry of the 60-Day Period, the Company shall have abandoned any Aircraft.

Class: Has the meaning specified in the Intercreditor Agreement.

Closing Notice: Has the meaning specified in the NPA.

Company: Has the meaning specified in the first paragraph of this Trust Supplement.

Controlling Party: Has the meaning specified in the Intercreditor Agreement.

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Cut-off Date: Means the earlier of (a) the Delivery Period Termination Date and (b) the date on which a Triggering Event occurs.

Delivery Period Termination Date: Means the earlier of (a) November 30, 2019 (provided that, if a labor strike occurs or continues at Boeing or Embraer after the Issuance Date and on or prior to such date referred to in this clause (a), such date shall be extended by adding thereto the number of days that such strike continued in effect after the Issuance Date, but not more than 60 days (such extended number of days, the “Strike Period”)) (provided that the Strike Period shall not include any day of a labor strike (1) at Boeing after the Applicable Trust and the United Airlines Pass Through Trust 2019-1AA-O shall have purchased, in accordance with the NPA, Equipment Notes issued to finance the Applicable Aircraft manufactured by Boeing or (2) at Embraer after the Applicable Trust and the United Airlines Pass Through Trust 2019-1AA-O shall have purchased, in accordance with the NPA, Equipment Notes issued to finance the Applicable Aircraft manufactured by Embraer), and (b) the date on which Equipment Notes issued with respect to all of the Applicable Aircraft (including any Substitute Aircraft in lieu of any New Applicable Aircraft) have been purchased by the Applicable Trust and the United Airlines Pass Through Trust 2019-1AA-O in accordance with the NPA.

Deposit Agreement: Means the Deposit Agreement dated as of February 11, 2019 relating to the Applicable Certificates between the Depositary and the Escrow Agent, as the same may be amended, supplemented or otherwise modified from time to time in accordance with its terms.

Depositary: Means Sumitomo Mitsui Banking Corporation, acting through its New York Branch.

Deposits: Has the meaning specified in the Deposit Agreement.

Distribution Date: Means any Regular Distribution Date or Special Distribution Date as the context requires.

Embraer: Means Embraer S.A.

ERISA: Has the meaning specified in Section 1.01(e) of this Trust Supplement.

Escrow Agent: Means, initially, U.S. Bank National Association and any replacement or successor therefor appointed in accordance with the Escrow Agreement.

Escrow Agreement: Means the Escrow and Paying Agent Agreement dated as of February 11, 2019 relating to the Applicable Certificates, among the Escrow Agent, the Escrow Paying Agent, the Trustee and the Underwriters, as the same may be amended, supplemented or otherwise modified from time to time in accordance with its terms.

Escrow Paying Agent: Means the Person acting as paying agent under the Escrow Agreement.

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Escrow Receipt: Means the receipt substantially in the form annexed to the Escrow Agreement representing a Fractional Undivided Interest in the funds held in escrow thereunder.

Final Distribution: Has the meaning specified in the Escrow Agreement.

Final Maturity Date: Means February 25, 2033.

Final Withdrawal: Has the meaning specified in the Escrow Agreement.

Final Withdrawal Date: Has the meaning specified in the Escrow Agreement.

Final Withdrawal Notice: Has the meaning specified in Section 5.02 of this Trust Supplement.

Indenture: Means each of the separate trust indentures and mortgages relating to the Aircraft, each as specified or described in a Closing Notice delivered pursuant to the NPA or the related Participation Agreement, in each case as the same may be amended, supplemented or otherwise modified from time to time in accordance with its terms.

Intercreditor Agreement: Means the Intercreditor Agreement dated as of February 11, 2019 among the Trustee, the Other Trustees party thereto, the Liquidity Provider, the liquidity provider relating to the Class AA Certificates and Wilmington Trust, National Association, as Subordination Agent and as trustee thereunder, as amended, supplemented or otherwise modified from time to time in accordance with its terms.

Investors: Means the Underwriters, together with all subsequent beneficial owners of the Applicable Certificates.

Issuance Date: Has the meaning specified in the NPA.

Liquidity Facility: Means, initially, the Revolving Credit Agreement dated as of February 11, 2019 relating to the Applicable Certificates, between the Liquidity Provider and Wilmington Trust, National Association, as Subordination Agent, as agent and trustee for the Applicable Trust, and, from and after the replacement of such agreement pursuant to the Intercreditor Agreement, the replacement liquidity facility therefor, in each case as amended, supplemented or otherwise modified from time to time in accordance with their respective terms.

Liquidity Provider: Means, initially, National Australia Bank Limited, acting through its New York Branch, and any replacements or successors therefor appointed in accordance with the Intercreditor Agreement.

Make-Whole Amount: Has the meaning specified in any Indenture.

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Note Documents: Means the Equipment Notes with respect to the Applicable Certificates and, with respect to any such Equipment Note, the Indenture and the Participation Agreement relating to such Equipment Note.

Notice of Purchase Withdrawal: Has the meaning specified in the Deposit Agreement.

NPA: Means the Note Purchase Agreement, dated as of the date hereof among the Trustee, the Other Trustees party thereto, the Company, the Escrow Agent, the Escrow Paying Agent and the Subordination Agent, providing for, among other things, the purchase of Equipment Notes by the Trustee on behalf of the Applicable Trust, as the same may be amended, supplemented or otherwise modified from time to time, in accordance with its terms.

Other Agreements: Means (i) the Basic Agreement, as supplemented by Trust Supplement No. 2019-1AA-O dated as of the date hereof relating to United Airlines Pass Through Trust 2019-1AA-O, (ii) the Basic Agreement, as supplemented by a Trust Supplement relating to any Additional Trust and (iii) the Basic Agreement, as supplemented by a Trust Supplement relating to any Refinancing Trust.

Other Trustees: Means the trustees under the Other Agreements, and any successor or other trustee appointed as provided therein.

Other Trusts: Means the United Airlines Pass Through Trust 2019-1AA-O, an Additional Trust or Trusts, if any, and a Refinancing Trust or Trusts, if any, created by the Other Agreements.

Participation Agreement: Means each Participation Agreement entered into by the Trustee pursuant to the NPA, as the same may be amended, supplemented or otherwise modified in accordance with its terms.

Pool Balance: Means, as of any date, (i) the original aggregate face amount of the Applicable Certificates, less (ii) the aggregate amount of all payments made as of such date in respect of such Applicable Certificates or in respect of Deposits, other than payments made in respect of interest or premium (including Make-Whole Amount) thereon or reimbursement of any costs or expenses incurred in connection therewith. The Pool Balance as of any date shall be computed after giving effect to any special distribution with respect to unused Deposits, payment of principal of the Equipment Notes or payment with respect to other Trust Property and the distribution thereof to be made on that date.

Pool Factor: Means, as of any Distribution Date, the quotient (rounded to the seventh decimal place) computed by dividing (i) the Pool Balance by (ii) the original aggregate face amount of the Applicable Certificates. The Pool Factor as of any Distribution Date shall be computed after giving effect to any special distribution with respect to unused Deposits, payment of principal of the Equipment Notes or payment with respect to other Trust Property and the distribution thereof to be made on that date.

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Prospectus Supplement: Means the final Prospectus Supplement dated January 28, 2019 relating to the offering of the Applicable Certificates and the Class AA Certificates.

Ratings Confirmation: Has the meaning specified in the Intercreditor Agreement.

Related Pass Through Trust Agreement: Means the Basic Agreement, as supplemented by the Trust Supplement No. 2019-1A-S dated as of the date hereof relating to the United Airlines Pass Through Trust 2019-1A-S and entered into by the Company and the Related Trustee, which agreement becomes effective upon the execution and delivery of the Assignment and Assumption Agreement pursuant to Section 7.01 of this Trust Supplement.

Related Trust: Means the United Airlines Pass Through Trust 2019-1A-S, to be formed under the Related Pass Through Trust Agreement.

Related Trustee: Means the trustee under the Related Pass Through Trust Agreement.

Scheduled Closing Date: Has the meaning specified in the NPA.

Scheduled Payment: Means, with respect to any Equipment Note, (i) any payment of principal or interest on such Equipment Note (other than any such payment which is not in fact received by the Trustee or the Subordination Agent within five days of the date on which such payment is scheduled to be made) or (ii) any payment of interest on the Applicable Certificates with funds drawn under the Liquidity Facility, which payment in any such case represents the installment of principal on such Equipment Note at the stated maturity of such installment, the payment of regularly scheduled interest accrued on the unpaid principal amount of such Equipment Note, or both; provided, however, that any payment of principal, premium (including Make-Whole Amount), if any, or interest resulting from the redemption or purchase of any Equipment Note shall not constitute a Scheduled Payment.

Special Payment: Means any payment (other than a Scheduled Payment) in respect of, or any proceeds of, any Equipment Note or Collateral (as defined in each Indenture).

Substitute Aircraft: Has the meaning specified in the NPA.

Transfer Date: Has the meaning specified in Section 7.01 of this Trust Supplement.

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Triggering Event: Has the meaning assigned to such term in the Intercreditor Agreement.

Trust Property: Means (i) subject to the Intercreditor Agreement, the Equipment Notes held as the property of the Applicable Trust, all monies at any time paid thereon or in respect thereof and all monies due and to become due thereunder, (ii) funds from time to time deposited in the Certificate Account and the Special Payments Account and, subject to the Intercreditor Agreement, any proceeds from the sale by the Trustee pursuant to Article VI of the Basic Agreement of any Equipment Note and (iii) all rights of the Applicable Trust and the Trustee, on behalf of the Applicable Trust, under the Intercreditor Agreement, the Escrow Agreement, the NPA and the Liquidity Facility, including, without limitation, all rights to receive certain payments thereunder, and all monies paid to the Trustee on behalf of the Applicable Trust pursuant to the Intercreditor Agreement or the Liquidity Facility, provided that rights with respect to the Deposits or under the Escrow Agreement, except for the right to direct withdrawals for the purchase of Equipment Notes to be held herein, will not constitute Trust Property.

Trust Supplement: Has the meaning specified in the first paragraph of this trust supplement.

Trustee: Has the meaning specified in the first paragraph of this Trust Supplement.

Underwriters: Means, collectively, Citigroup Global Markets Inc., Credit Suisse Securities (USA) LLC, Goldman Sachs & Co. LLC, Deutsche Bank Securities Inc., Morgan Stanley & Co. LLC, J.P. Morgan Securities LLC, Barclays Capital Inc., Merrill Lynch, Pierce, Fenner & Smith Incorporated, BBVA Securities Inc., BNP Paribas Securities Corp., Credit Agricole Securities (USA) Inc., Standard Chartered Bank and Wells Fargo Securities, LLC.

Underwriting Agreement: Means the Underwriting Agreement related to the Applicable Certificates dated January 28, 2019 among Citigroup Global Markets Inc. and Credit Suisse Securities (USA) LLC, as representatives of the several Underwriters, the Company and the Depositary, as the same may be amended, supplemented or otherwise modified from time to time in accordance with its terms.

United Bankruptcy Event: Has the meaning specified in the Intercreditor Agreement.

ARTICLE III

DISTRIBUTIONS; STATEMENTS TO CERTIFICATEHOLDERS

Section 3.01. Statements to Applicable Certificateholders. (a) On each Distribution Date, the Trustee will include with each distribution to Applicable Certificateholders of a Scheduled Payment or Special Payment, as the case may be, a statement setting forth the information provided below (in the case of a Special Payment, reflecting in part the information provided by the Escrow Paying Agent under the Escrow Agreement). Such statement shall set forth (per $1,000 face amount Applicable Certificate as to (ii), (iii), (iv) and (v) below) the following information:

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(i)    The aggregate amount of funds distributed on such Distribution Date under the Agreement and under the Escrow Agreement, indicating the amount allocable to each source, including any portion thereof paid by the Liquidity Provider;

(ii)    The amount of such distribution under the Agreement allocable to principal and the amount allocable to premium (including Make-Whole Amount), if any;

(iii)    The amount of such distribution under the Agreement allocable to interest;

(iv)    The amount of such distribution under the Escrow Agreement allocable to interest;

(v)    The amount of such distribution under the Escrow Agreement allocable to unused Deposits, if any; and

(vi)    The Pool Balance and the Pool Factor.

With respect to the Applicable Certificates registered in the name of a Clearing Agency or its nominee, on the Record Date prior to each Distribution Date, the Trustee will request that such Clearing Agency post on its Internet bulletin board a securities position listing setting forth the names of all Clearing Agency Participants reflected on such Clearing Agency’s books as holding interests in the Applicable Certificates on such Record Date. On each Distribution Date, the Trustee will mail to each such Clearing Agency Participant the statement described above and will make available additional copies as requested by such Clearing Agency Participant for forwarding to holders of interests in the Applicable Certificates.

(b)    Within a reasonable period of time after the end of each calendar year but not later than the latest date permitted by law, the Trustee shall furnish to each Person who at any time during such calendar year was an Applicable Certificateholder of record a statement containing the sum of the amounts determined pursuant to clauses (a)(i), (a)(ii), (a)(iii), (a)(iv) and (a)(v) above for such calendar year or, in the event such Person was an Applicable Certificateholder of record during a portion of such calendar year, for such portion of such year, and such other items as are readily available to the Trustee and which an Applicable Certificateholder shall reasonably request as necessary for the purpose of such Applicable Certificateholder’s preparation of its U.S. federal income tax returns. Such statement and such other items shall be prepared on the basis of information supplied to the Trustee by the Clearing Agency Participants and shall be delivered by the Trustee to such Clearing Agency Participants to be available for forwarding by such Clearing Agency Participants to the holders of interests in the Applicable Certificates in the manner described in Section 3.01(a) of this Trust Supplement.

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(c)    If the aggregate principal payments scheduled for a Regular Distribution Date prior to the Delivery Period Termination Date differ from the amount thereof set forth for the Applicable Certificates on page S-39 of the Prospectus Supplement, by no later than the 15th day prior to such Regular Distribution Date, the Trustee shall mail written notice of the actual amount of such scheduled payments to the Applicable Certificateholders of record as of a date within 15 Business Days prior to the date of mailing. If the Trustee has given such notice, the Company shall not give a “Closing Notice” (as defined in the NPA) under the NPA providing for a “Funding Date” (as defined in the NPA) on or after the date the Trustee gives such notice and on or prior to such Regular Distribution Date and shall revoke any Closing Notice previously given that provides for such a Funding Date.

(d)    Promptly following (i) the Delivery Period Termination Date, if there has been any change in the information set forth in clauses (y) and (z) below from that set forth on page S-39 of the Prospectus Supplement, and (ii) the date of any early redemption of, or any default in the payment of principal or interest in respect of, any of the Equipment Notes held in the Applicable Trust, or any Final Withdrawal, the Trustee shall furnish to Applicable Certificateholders of record on such date a statement setting forth (x) the expected Pool Balances for each subsequent Regular Distribution Date following the Delivery Period Termination Date, (y) the related Pool Factors for such Regular Distribution Dates and (z) the expected principal payment schedule of the Equipment Notes, in the aggregate, held as Trust Property at the date of such notice. With respect to the Applicable Certificates registered in the name of a Clearing Agency, on the Delivery Period Termination Date, the Trustee will request from such Clearing Agency a securities position listing setting forth the names of all Clearing Agency Participants reflected on such Clearing Agency’s books as holding interests in the Applicable Certificates on such date. The Trustee will mail to each such Clearing Agency Participant the statement described above and will make available additional copies as requested by such Clearing Agency Participant for forwarding to holders of interests in the Applicable Certificates.

(e)    The Trustee shall provide promptly to the Applicable Certificateholders all material non-confidential information received by the Trustee from the Company.

(f)     This Section 3.01 supersedes and replaces Section 4.03 of the Basic Agreement, with respect to the Applicable Trust.

Section 3.02. Special Payments Account. (a) The Trustee shall establish and maintain on behalf of the Applicable Certificateholders a Special Payments Account as one or more accounts, which shall be non-interest bearing except as provided in Section 4.04 of the Basic Agreement. The Trustee shall hold the Special Payments Account in trust for the benefit of the Applicable Certificateholders and shall make or permit withdrawals therefrom only as provided in the Agreement. On each day when one or more Special Payments are made to the Trustee under the Intercreditor Agreement, the Trustee, upon receipt thereof, shall immediately deposit the aggregate amount of such Special Payments in the Special Payments Account.

(b)     This Section 3.02 supersedes and replaces Section 4.01(b) of the Basic Agreement in its entirety, with respect to the Applicable Trust.

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Section 3.03. Distributions from Special Payments Account. (a) On each Special Distribution Date with respect to any Special Payment or as soon thereafter as the Trustee has confirmed receipt of any Special Payments due on the Equipment Notes held (subject to the Intercreditor Agreement) in the Applicable Trust or realized upon the sale of such Equipment Notes, the Trustee shall distribute out of the Special Payments Account the entire amount of such Special Payment deposited therein pursuant to Section 3.02(a) of this Trust Supplement. There shall be so distributed to each Applicable Certificateholder of record on the Record Date with respect to such Special Distribution Date (other than as provided in Section 7.01 of this Trust Supplement concerning the final distribution) by check mailed to such Applicable Certificateholder, at the address appearing in the Register, such Applicable Certificateholder’s pro rata share (based on the Fractional Undivided Interest in the Applicable Trust held by such Applicable Certificateholder) of the total amount in the Special Payments Account on account of such Special Payment, except that, with respect to Applicable Certificates registered on the Record Date in the name of a Clearing Agency (or its nominee), such distribution shall be made by wire transfer in immediately available funds to the account designated by such Clearing Agency (or such nominee).

(b)    The Trustee shall, at the expense of the Company, cause notice of each Special Payment to be mailed to each Applicable Certificateholder at his address as it appears in the Register. In the event of redemption or purchase of Equipment Notes held in the Applicable Trust, such notice shall be mailed not less than 15 days prior to the Special Distribution Date for the Special Payment resulting from such redemption or purchase, which Special Distribution Date shall be the date of such redemption or purchase. In the case of any other Special Payments, such notice shall be mailed as soon as practicable after the Trustee has confirmed that it has received funds for such Special Payment, stating the Special Distribution Date for such Special Payment which shall occur not less than 15 days after the date of such notice and as soon as practicable thereafter. Notices with respect to a Special Payment mailed by the Trustee shall set forth:

(i)    The Special Distribution Date and the Record Date therefor (except as otherwise provided in Section 7.01 of this Trust Supplement),

(ii)    The amount of the Special Payment for each $1,000 face amount Applicable Certificate and the amount thereof constituting principal, premium (including Make-Whole Amount), if any, and interest,

(iii)    The reason for the Special Payment, and

(iv)    If the Special Distribution Date is the same date as a Regular Distribution Date, the total amount to be received on such date for each $1,000 face amount Applicable Certificate.

If the amount of premium (including Make-Whole Amount), if any, payable upon the redemption or purchase of an Equipment Note has not been calculated at the time that the Trustee mails notice of a Special Payment, it shall be sufficient if the notice sets forth the other amounts to be distributed and states that any premium (including Make-Whole Amount) received will also be distributed.

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If any redemption of the Equipment Notes held in the Applicable Trust is canceled, the Trustee, as soon as possible after learning thereof, shall cause notice thereof to be mailed to each Applicable Certificateholder at its address as it appears on the Register.

(c)     This Section 3.03 supersedes and replaces Section 4.02(b) and Section 4.02(c) of the Basic Agreement in their entirety, with respect to the Applicable Trust.

Section 3.04. Limitation of Liability for Payments. Section 3.09 of the Basic Agreement shall be amended, with respect to the Applicable Trust, by deleting the phrase “the Owner Trustees or the Owner Participants” in the second sentence thereof and adding in lieu thereof “the Liquidity Provider”.

ARTICLE IV

DEFAULT

Section 4.01. Purchase Rights of Certificateholders. (a) By acceptance of its Applicable Certificate, each Applicable Certificateholder agrees that at any time after the occurrence and during the continuation of a Certificate Buyout Event:

(i)     So long as no Additional Certificateholder has elected to exercise its rights to purchase Certificates pursuant to, and given notice of such election in accordance with, this Section 4.01(a) (upon such election and notification thereof, the right specified in this Section 4.01(a)(i) shall be suspended and (x) upon consummation of such purchase pursuant to such election, be terminated with respect to such Certificate Buyout Event, or (y) upon failure to consummate such purchase on the proposed purchase date, such right shall be reinstated), each Applicable Certificateholder (other than the Company or any of its Affiliates) shall have the right to purchase, for the purchase price set forth in the Class AA Trust Agreement, all, but not less than all, of the Class AA Certificates upon 15 days’ written notice to the Class AA Trustee and each other Applicable Certificateholder, on the third Business Day next following the expiry of such 15-day notice period, provided that (A) if prior to the end of such 15-day period any other Applicable Certificateholder (other than the Company or any of its Affiliates) notifies such purchasing Applicable Certificateholder that such other Applicable Certificateholder wants to participate in such purchase, then such other Applicable Certificateholder (other than the Company or any of its Affiliates) may join with the purchasing Applicable Certificateholder to purchase all, but not less than all, of the Class AA Certificates pro rata based on the Fractional Undivided Interest in the Applicable Trust held by each such Applicable Certificateholder and (B) if prior to the end of such 15-day period any other Applicable Certificateholder fails to notify the purchasing Applicable Certificateholder of such other Applicable Certificateholder’s desire to participate in such a purchase, then such other Applicable Certificateholder shall lose its right to purchase the Class AA Certificates pursuant to this Section 4.01(a)(i);

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(ii)    If any Additional Certificates are issued pursuant to one or more Additional Trusts, each Additional Certificateholder (other than the Company or any of its Affiliates) shall have the right (which shall not expire upon any purchase of the Class AA Certificates pursuant to clause (i) above) to purchase all, but not less than all, of the Class AA Certificates, the Applicable Certificates, and any Additional Certificates ranked senior to the Additional Certificates held by the purchasing Additional Certificateholders upon 15 days’ written notice to the Trustee, the Class AA Trustee, any Additional Trustee with respect to Additional Certificates that rank senior to the Additional Certificates held by the purchasing Additional Certificateholders and each other Additional Certificateholder of the same class, on the third Business Day next following the expiry of such 15-day notice period, provided that (A) if prior to the end of such 15-day period any other Additional Certificateholder of such class (other than the Company or any of its Affiliates) notifies such purchasing Additional Certificateholder that such other Additional Certificateholder wants to participate in such purchase, then such other Additional Certificateholder (other than the Company or any of its Affiliates) may join with the purchasing Additional Certificateholder to purchase all, but not less than all, of the Class AA Certificates, the Applicable Certificates and such senior Additional Certificates pro rata based on the Fractional Undivided Interest in the applicable Additional Trust held by each such Additional Certificateholder and (B) if prior to the end of such 15-day period any other Additional Certificateholder of such class fails to notify the purchasing Additional Certificateholder of such other Additional Certificateholder’s desire to participate in such a purchase, then such other Additional Certificateholder shall lose its right to purchase the Class AA Certificates, the Applicable Certificates and such senior Additional Certificates pursuant to this Section 4.01(a)(ii); and

(iii)     If any Refinancing Certificates are issued, each Refinancing Certificateholder shall have the same right (subject to the same terms and conditions) to purchase Certificates pursuant to this Section 4.01(a) (and to receive notice in connection therewith) as the Certificateholders of the Class that such Refinancing Certificates refinanced.

The purchase price with respect to the Applicable Certificates shall be equal to the Pool Balance of the Applicable Certificates, together with accrued and unpaid interest thereon to the date of such purchase, without premium (including Make-Whole Amount), but including any other amounts then due and payable to the Applicable Certificateholders under the Agreement, the Intercreditor Agreement, the Escrow Agreement or any Note Document or on or in respect of the Applicable Certificates; provided, however, that no such purchase of Applicable Certificates shall be effective unless the purchaser(s) shall certify to the Trustee that contemporaneously with such purchase, such purchaser(s) is (are) purchasing, pursuant to the terms of the Agreement and the Other Agreements, all of the Applicable Certificates, the Class AA Certificates and, if applicable, the Additional Certificates that rank senior to the Additional Certificates held by the purchasing Additional Certificateholder(s). Each payment of the purchase price of the Applicable Certificates referred to in the first sentence hereof shall be made to an account or accounts designated by the Trustee and each such purchase shall be subject to the terms of this Section 4.01. Each Applicable Certificateholder agrees by its acceptance of its Applicable Certificate that (at any time after the occurrence of a Certificate Buyout Event) it will, upon payment from such Class AA Certificateholder(s), Additional Certificateholder(s) or Refinancing Certificateholder(s), as the case may be, of the purchase price set forth in the first sentence of

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this paragraph, (i) forthwith sell, assign, transfer and convey to the purchaser(s) thereof (without recourse, representation or warranty of any kind except for its own acts), all of the right, title, interest and obligation of such Applicable Certificateholder in the Agreement, the Escrow Agreement, the Deposit Agreement, the Intercreditor Agreement, the Liquidity Facility, the NPA, the Note Documents and all Applicable Certificates and Escrow Receipts held by such Applicable Certificateholder (excluding all right, title and interest under any of the foregoing to the extent such right, title or interest is with respect to an obligation not then due and payable as respects any action or inaction or state of affairs occurring prior to such sale) (and the purchaser shall assume all of such Applicable Certificateholder’s obligations under the Agreement, the Escrow Agreement, the Deposit Agreement, the Intercreditor Agreement, the Liquidity Facility, the NPA, the Note Documents and all such Applicable Certificates and Escrow Receipts), (ii) if such purchase occurs after a record date specified in Section 2.03 of the Escrow Agreement relating to the distribution of unused Deposits and/or accrued and unpaid interest on Deposits and prior to or on the related distribution date thereunder, forthwith turn over to the purchaser(s) of its Applicable Certificate all amounts, if any, received by it on account of such distribution, and (iii) if such purchase occurs after a Record Date relating to any distribution and prior to or on the related Distribution Date, forthwith turn over to the purchaser(s) of its Applicable Certificate all amounts, if any, received by it on account of such distribution. The Applicable Certificates will be deemed to be purchased on the date payment of the purchase price is made notwithstanding the failure of the Applicable Certificateholders to deliver any Applicable Certificates and, upon such a purchase, (I) the only rights of the Applicable Certificateholders will be to deliver the Applicable Certificates to the purchaser(s) and receive the purchase price for such Applicable Certificates and (II) if the purchaser(s) shall so request, such Applicable Certificateholder will comply with all the provisions of Section 3.04 of the Basic Agreement to enable new Applicable Certificates to be issued to the purchaser in such denominations as it shall request. All charges and expenses in connection with the issuance of any such new Applicable Certificates shall be borne by the purchaser thereof.

As used in this Section 4.01 and elsewhere in this Trust Supplement, the terms “Additional Certificate”, “Additional Certificateholder”, “Additional Equipment Notes”, “Additional Trust”, “Class AA Certificate”, “Class AA Certificateholder”, “Class AA Trust”, “Class AA Trust Agreement”, “Class AA Trustee”, “Refinancing Certificates”, “Refinancing Certificateholder”, “Refinancing Equipment Notes” and “Refinancing Trust” shall have the respective meanings assigned to such terms in the Intercreditor Agreement.

(b)    This Section 4.01 supersedes and replaces Section 6.01(b) of the Basic Agreement, with respect to the Applicable Trust.

Section 4.02. Amendment of Section 6.05 of the Basic Agreement. Section 6.05 of the Basic Agreement shall be amended, with respect to the Applicable Trust, by deleting the phrase “and thereby annul any Direction given by such Certificateholders or the Trustee to such Loan Trustee with respect thereto,” set forth in the first sentence thereof.

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ARTICLE V

THE TRUSTEE

Section 5.01. Delivery of Documents; Delivery Dates. (a) The Trustee is hereby directed (i) to execute and deliver the Intercreditor Agreement, the Escrow Agreement and the NPA on or prior to the Issuance Date, each in the form delivered to the Trustee by the Company, and (ii) subject to the respective terms thereof, to perform its obligations thereunder. Upon request of the Company and the satisfaction or waiver of the closing conditions specified in the Underwriting Agreement, the Trustee shall execute, deliver, authenticate, issue and sell Applicable Certificates in authorized denominations equaling in the aggregate the amount set forth, with respect to the Applicable Trust, in Schedule I to the Underwriting Agreement evidencing the entire ownership interest in the Applicable Trust, which amount equals the maximum aggregate principal amount of Equipment Notes which may be purchased by the Trustee pursuant to the NPA. Except as provided in Sections 3.03, 3.04, 3.05 and 3.06 of the Basic Agreement, the Trustee shall not execute, authenticate or deliver Applicable Certificates in excess of the aggregate amount specified in this paragraph. The provisions of this Section 5.01(a) supersede and replace the first sentence of Section 3.02(a) of the Basic Agreement, with respect to the Applicable Trust.

(b)    After the Issuance Date, the Company may deliver from time to time to the Trustee a Closing Notice relating to one or more Equipment Notes. After receipt of a Closing Notice and in any case no later than one Business Day prior to a Scheduled Closing Date as to which such Closing Notice relates (the “Applicable Closing Date”), the Trustee shall (as and when specified in the Closing Notice) instruct the Escrow Agent to provide a Notice of Purchase Withdrawal to the Depositary requesting (i) the withdrawal of one or more Deposits on the Applicable Closing Date in accordance with and to the extent permitted by the terms of the Escrow Agreement and the Deposit Agreement and (ii) the payment of all, or a portion, of such Deposit or Deposits in an amount equal in the aggregate to the purchase price of such Equipment Notes to or on behalf of the Company, all as shall be described in the Closing Notice. The Trustee shall (as and when specified in such Closing Notice), subject to the conditions set forth in Section 2 of the NPA, enter into and perform its obligations under the Participation Agreement specified in such Closing Notice (the “Applicable Participation Agreement”) and cause such certificates, documents and legal opinions relating to the Trustee to be duly delivered as required by the Applicable Participation Agreement. If at any time prior to the Applicable Closing Date, the Trustee receives a notice of postponement pursuant to Section 1(e) or 1(f) of the NPA, then the Trustee shall give the Depositary (with a copy to the Escrow Agent) a notice of cancellation of such Notice of Purchase Withdrawal relating to such Deposit or Deposits on such Applicable Closing Date. Upon satisfaction of the conditions specified in the NPA and the Applicable Participation Agreement, the Trustee shall purchase the applicable Equipment Notes with the proceeds of the withdrawals of one or more Deposits made on the Applicable Closing Date in accordance with the terms of the Deposit Agreement and the Escrow Agreement. The purchase price of such Equipment Notes shall equal the principal amount of such Equipment Notes. Amounts withdrawn from such Deposit or Deposits in excess of the purchase price of the Equipment Notes or to the extent not applied on the Applicable Closing Date to the purchase price of the Equipment Notes, shall be re-deposited by the Trustee with the Depositary on the Applicable Closing Date in accordance with the terms of the Deposit Agreement. The provisions of this Section 5.01(b) supersede and replace the provisions of Section 2.02 of the Basic Agreement with respect to the Applicable Trust, and all provisions of the Basic Agreement relating to Postponed Notes and Section 2.02 of the Basic Agreement shall not apply to the Applicable Trust.

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(c)     The Trustee acknowledges its acceptance of all right, title and interest in and to the Trust Property to be acquired pursuant to Section 5.01(b) of this Trust Supplement, the NPA and each Applicable Participation Agreement, and declares that it holds and will hold such right, title and interest for the benefit of all present and future Applicable Certificateholders, upon the trusts set forth in the Agreement. By its acceptance of an Applicable Certificate, each initial Applicable Certificateholder, as a grantor of the Applicable Trust, joins with the Trustee in the creation of the Applicable Trust. The provisions of this Section 5.01(c) supersede and replace the provisions of Section 2.03 of the Basic Agreement, with respect to the Applicable Trust.

Section 5.02. Withdrawal of Deposits. If any Deposits remain outstanding on the Business Day next succeeding the Cut-off Date, the Trustee shall promptly give the Escrow Agent notice that the Trustee’s obligation to purchase Equipment Notes under the NPA has terminated and instruct the Escrow Agent to provide a notice of Final Withdrawal to the Depositary substantially in the form of Exhibit B to the Deposit Agreement (the “Final Withdrawal Notice”).

Section 5.03. The Trustee. (a) Subject to Section 5.04 of this Trust Supplement and Section 7.15 of the Basic Agreement, the Trustee shall not be responsible in any manner whatsoever for or in respect of the validity or sufficiency of this Trust Supplement, the Deposit Agreement, the NPA or the Escrow Agreement or the due execution hereof or thereof by the Company or the other parties thereto (other than the Trustee), or for or in respect of the recitals and statements contained herein or therein, all of which recitals and statements are made solely by the Company, except that the Trustee hereby represents and warrants that each of this Trust Supplement, the Basic Agreement, each Applicable Certificate, the Intercreditor Agreement, the NPA and the Escrow Agreement has been executed and delivered by one of its officers who is duly authorized to execute and deliver such document on its behalf.

(b)    Except as herein otherwise provided and except during the continuation of an Event of Default in respect of the Applicable Trust created hereby, no duties, responsibilities or liabilities are assumed, or shall be construed to be assumed, by the Trustee by reason of this Trust Supplement other than as set forth in the Agreement, and this Trust Supplement is executed and accepted on behalf of the Trustee, subject to all the terms and conditions set forth in the Agreement, as fully to all intents as if the same were herein set forth at length.

Section 5.04. Representations and Warranties of the Trustee. The Trustee hereby represents and warrants that:

(a)    The Trustee has full power, authority and legal right to execute, deliver and perform this Trust Supplement, the Intercreditor Agreement, the Escrow Agreement, the NPA and the Note Documents to which it is or is to become a party and has taken all necessary action to authorize the execution, delivery and performance by it of this Trust Supplement, the Intercreditor Agreement, the Escrow Agreement, the NPA and the Note Documents to which it is or is to become a party;

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(b)    The execution, delivery and performance by the Trustee of this Trust Supplement, the Intercreditor Agreement, the Escrow Agreement, the NPA and the Note Documents to which it is or is to become a party (i) will not violate any provision of any United States federal law or the law of the state of the United States where it is located governing the banking and trust powers of the Trustee or any order, writ, judgment, or decree of any court, arbitrator or governmental authority applicable to the Trustee or any of its assets, (ii) will not violate any provision of the articles of association or by-laws of the Trustee, and (iii) will not violate any provision of, or constitute, with or without notice or lapse of time, a default under, or result in the creation or imposition of any lien on any properties included in the Trust Property pursuant to the provisions of any mortgage, indenture, contract, agreement or other undertaking to which it is a party, which violation, default or lien could reasonably be expected to have an adverse effect on the Trustee’s performance or ability to perform its duties hereunder or thereunder or on the transactions contemplated herein or therein;

(c)    The execution, delivery and performance by the Trustee of this Trust Supplement, the Intercreditor Agreement, the Escrow Agreement, the NPA and the Note Documents to which it is or is to become a party will not require the authorization, consent, or approval of, the giving of notice to, the filing or registration with, or the taking of any other action in respect of, any governmental authority or agency of the United States or the state of the United States where it is located regulating the banking and corporate trust activities of the Trustee; and

(d)    This Trust Supplement, the Intercreditor Agreement, the Escrow Agreement, the NPA and the Note Documents to which it is or is to become a party have been, or will be, as applicable, duly executed and delivered by the Trustee and constitute, or will constitute, as applicable, the legal, valid and binding agreements of the Trustee, enforceable against it in accordance with their respective terms; provided, however, that enforceability may be limited by (i) applicable bankruptcy, insolvency, reorganization, moratorium or similar laws affecting the rights of creditors generally and (ii) general principles of equity.

Section 5.05. Trustee Liens. The Trustee in its individual capacity agrees, in addition to the agreements contained in Section 7.17 of the Basic Agreement, that it will at its own cost and expense promptly take any action as may be necessary to duly discharge and satisfy in full any Trustee’s Liens on or with respect to the Trust Property which is attributable to the Trustee in its individual capacity and which is unrelated to the transactions contemplated by the Intercreditor Agreement or the NPA.

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ARTICLE VI

ADDITIONAL AMENDMENT; SUPPLEMENTAL AGREEMENTS

Section 6.01. Amendment of Section 5.02 of the Basic Agreement. Section 5.02 of the Basic Agreement shall be amended, with respect to the Applicable Trust, by (i) replacing the phrase “of the Note Documents and of this Agreement” set forth in paragraph (b) thereof with the phrase “of the Note Documents, of the NPA and of this Agreement” and (ii) replacing the phrase “of this Agreement and any Note Document” set forth in the last paragraph of Section 5.02 with the phrase “of this Agreement, the NPA and any Note Document”.

Section 6.02. Supplemental Agreements without Consent of Applicable Certificateholders. Without limitation of Section 9.01 of the Basic Agreement, under the terms of, and subject to the limitations contained in, Section 9.01 of the Basic Agreement, the Company may (but will not be required to), and the Trustee (subject to Section 9.03 of the Basic Agreement) shall, at the Company’s request, at any time and from time to time:

(i)     Enter into one or more agreements supplemental to the Escrow Agreement, the NPA or the Deposit Agreement for any of the purposes set forth in clauses (1) through (9) of such Section 9.01, and (without limitation of the foregoing or Section 9.01 of the Basic Agreement) (a) clauses (2) and (3) of such Section 9.01 shall also be deemed to include the Company’s obligations under (in the case of clause (2)), and the Company’s rights and powers conferred by (in the case of clause (3)), the NPA, and (b) references in clauses (4), (6) and (7) of such Section 9.01 to “any Intercreditor Agreement or any Liquidity Facility” shall also be deemed to refer to “the Intercreditor Agreement, the Liquidity Facility, the Escrow Agreement, the NPA or the Deposit Agreement”,

(ii)    Enter into one or more agreements supplemental to the Agreement, the Intercreditor Agreement or the NPA to provide for the formation of one or more Additional Trusts, the issuance of Additional Certificates, the purchase by an Additional Trust (if any) of applicable Additional Equipment Notes and other matters incidental thereto or otherwise contemplated by Section 2.01(b) of the Basic Agreement, subject to the provisions of Section 4(a)(vi) of the NPA and Section 9.1(d) of the Intercreditor Agreement, and

(iii)     Enter into one or more agreements supplemental to the Agreement to provide for the formation of one or more Refinancing Trusts, the issuance of Refinancing Certificates, the purchase by any Refinancing Trust of applicable Refinancing Equipment Notes and other matters incidental thereto or as otherwise contemplated by Section 2.01(b) of the Basic Agreement, subject to the provisions of Section 4(a)(vi) of the NPA and Section 9.1(c) of the Intercreditor Agreement.

Section 6.03. Supplemental Agreements with Consent of Applicable Certificateholders. Without limitation of Section 9.02 of the Basic Agreement, the provisions of Section 9.02 of the Basic Agreement shall apply to agreements or amendments for the purpose of adding any provisions to or changing in any manner or eliminating any of the provisions of the Escrow Agreement, the Deposit Agreement, the Liquidity Facility or the NPA or modifying in any manner the rights and obligations of the Applicable Certificateholders under the Escrow Agreement, the Deposit Agreement, the Liquidity Facility or the NPA; provided that the provisions of Section 9.02(1) of the Basic Agreement shall be deemed to include reductions in any manner of, or delay in the timing of, any receipt by the Applicable Certificateholders of payments upon the Deposits.

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Section 6.04. Consent of Holders of Certificates Issued under Other Trusts. Notwithstanding any provision in Section 6.02 or Section 6.03 of this Trust Supplement to the contrary, no amendment or modification of Section 4.01 of this Trust Supplement shall be effective unless the trustee for each Class of Certificates affected by such amendment or modification shall have consented thereto.

ARTICLE VII

TERMINATION OF TRUST

Section 7.01. Termination of the Applicable Trust. (a) The respective obligations and responsibilities of the Company and the Trustee with respect to the Applicable Trust shall terminate upon the earlier of (i) the completion of the assignment, transfer and discharge described in the first sentence of the immediately following paragraph and (ii) distribution to all Applicable Certificateholders and the Trustee of all amounts required to be distributed to them pursuant to the Agreement and the disposition of all property held as part of the Trust Property; provided, however, that in no event shall the Applicable Trust continue beyond one hundred ten (110) years following the date of the execution of this Trust Supplement.

Upon the earlier of (i) the first Business Day following November 30, 2019 or, if later, the fifth Business Day following the Delivery Period Termination Date and (ii) the fifth Business Day following the date on which a Triggering Event occurs (such date, the “Transfer Date”), or, if later, the date on which all of the conditions set forth in the immediately following sentence have been satisfied, the Trustee is hereby directed (subject only to the immediately following sentence) to, and the Company shall direct the institution that will serve as the Related Trustee under the Related Pass Through Trust Agreement to, execute and deliver the Assignment and Assumption Agreement, pursuant to which the Trustee shall assign, transfer and deliver all of the Trustee’s right, title and interest to the Trust Property to the Related Trustee under the Related Pass Through Trust Agreement. The Trustee and the Related Trustee shall execute and deliver the Assignment and Assumption Agreement upon the satisfaction of the following conditions:

(i)    The Trustee, the Related Trustee and each of the Rating Agencies then rating the Applicable Certificates shall have received an Officer’s Certificate and an Opinion of Counsel dated the date of the Assignment and Assumption Agreement and each satisfying the requirements of Section 1.02 of the Basic Agreement, which Opinion of Counsel shall be substantially to the effect set forth below and may be relied upon by the Beneficiaries (as defined in the Assignment and Assumption Agreement):

(I)    Upon the execution and delivery thereof by the parties thereto in accordance with the terms of the Agreement and the Related Pass Through Trust Agreement, the Assignment and Assumption Agreement will constitute the valid and binding obligation of each of the parties thereto enforceable against each such party in accordance with its terms;

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(II)    Upon the execution and delivery of the Assignment and Assumption Agreement in accordance with the terms of the Agreement and the Related Pass Through Trust Agreement, each of the Applicable Certificates then Outstanding will be entitled to the benefits of the Related Pass Through Trust Agreement;

(III)    The Related Trust is not required to be registered as an investment company under the Investment Company Act of 1940, as amended;

(IV)    The Related Pass Through Trust Agreement constitutes the valid and binding obligation of the Company enforceable against the Company in accordance with its terms; and

(V)    Neither the execution and delivery of the Assignment and Assumption Agreement in accordance with the terms of the Agreement and the Related Pass Through Trust Agreement, nor the consummation by the parties thereto of the transactions contemplated to be consummated thereunder on the date thereof, will violate any law or governmental rule or regulation of the State of New York or the United States of America known to such counsel to be applicable to the transactions contemplated by the Assignment and Assumption Agreement.

(ii)    The Trustee and the Company shall have received (x) a copy of the articles of incorporation and bylaws of the Related Trustee certified as of the Transfer Date by the Secretary or Assistant Secretary of such institution and (y) a copy of the filing (including all attachments thereto) made by the institution serving as the Related Trustee with the Office of the Superintendent, State of New York Banking Department for the qualification of the Related Trustee under Section 131(3) of the New York Banking Law, if applicable to such Related Trustee.

Upon the execution of the Assignment and Assumption Agreement by the parties thereto, the Applicable Trust shall be terminated, the Applicable Certificateholders shall receive beneficial interests in the Related Trust in exchange for their interests in the Applicable Trust equal to their respective beneficial interests in the Applicable Trust, and the Outstanding Applicable Certificates representing Fractional Undivided Interests in the Applicable Trust shall be deemed for all purposes of the Agreement and the Related Pass Through Trust Agreement, without further signature or action of any party or Applicable Certificateholder, to be certificates representing the same Fractional Undivided Interests in the Related Trust and its trust property. By acceptance of its Applicable Certificate, each Applicable Certificateholder consents to such assignment, transfer and delivery of the Trust Property to the trustee of the Related Trust upon the execution and delivery of the Assignment and Assumption Agreement.

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In connection with the occurrence of the event set forth in clause (ii) above of the first paragraph of this Section 7.01(a), notice of such termination, specifying the Distribution Date upon which the Applicable Certificateholders may surrender their Applicable Certificates to the Trustee for payment of the final distribution and cancellation, shall be mailed promptly by the Trustee to Applicable Certificateholders not earlier than the 60th day and not later than the 15th day next preceding such final Distribution Date specifying (A) the Distribution Date upon which the proposed final payment of the Applicable Certificates will be made upon presentation and surrender of Applicable Certificates at the office or agency of the Trustee therein specified, (B) the amount of any such proposed final payment, and (C) that the Record Date otherwise applicable to such Distribution Date is not applicable, payments being made only upon presentation and surrender of the Applicable Certificates at the office or agency of the Trustee therein specified. The Trustee shall give such notice to the Registrar at the time such notice is given to Applicable Certificateholders. Upon presentation and surrender of the Applicable Certificates in accordance with such notice, the Trustee shall cause to be distributed to Applicable Certificateholders such final payments.

In the event that all of the Applicable Certificateholders shall not surrender their Applicable Certificates for cancellation within six months after the date specified in the above-mentioned written notice, the Trustee shall give a second written notice to the remaining Applicable Certificateholders to surrender their Applicable Certificates for cancellation and receive the final distribution with respect thereto. No additional interest shall accrue on the Applicable Certificates after the Distribution Date specified in the first written notice. In the event that any money held by the Trustee for the payment of distributions on the Applicable Certificates shall remain unclaimed for two years (or such lesser time as the Trustee shall be satisfied, after sixty days’ notice from the Company, is one month prior to the escheat period provided under applicable law) after the final distribution date with respect thereto, the Trustee shall pay to each Loan Trustee the appropriate amount of money relating to such Loan Trustee and shall give written notice thereof to the Company.

(b)     The provisions of this Section 7.01 supersede and replace the provisions of Section 11.01 of the Basic Agreement in its entirety, with respect to the Applicable Trust.

ARTICLE VIII

MISCELLANEOUS PROVISIONS

Section 8.01. Basic Agreement Ratified. Except and so far as herein expressly provided, all of the provisions, terms and conditions of the Basic Agreement are in all respects ratified and confirmed; and the Basic Agreement and this Trust Supplement shall be taken, read and construed as one and the same instrument. All replacements of provisions of, and other modifications of the Basic Agreement set forth in this Trust Supplement are solely with respect to the Applicable Trust.

Section 8.02. GOVERNING LAW. THE AGREEMENT AND, UNTIL THE TRANSFER DATE, THE APPLICABLE CERTIFICATES SHALL BE GOVERNED BY AND CONSTRUED IN ACCORDANCE WITH THE LAWS OF THE STATE OF DELAWARE. THIS SECTION 8.02 SUPERSEDES AND REPLACES SECTION 12.05 OF THE BASIC AGREEMENT, WITH RESPECT TO THE APPLICABLE TRUST.

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Section 8.03. Execution in Counterparts. This Trust Supplement may be executed in any number of counterparts, each of which shall be an original, but such counterparts shall together constitute but one and the same instrument.

Section 8.04. Intention of Parties. The parties hereto intend that the Applicable Trust be classified for U.S. federal income tax purposes as a grantor trust under Subpart E, Part I of Subchapter J of the Internal Revenue Code of 1986, as amended, and not as a trust or association taxable as a corporation or as a partnership. Each Applicable Certificateholder and Investor, by its acceptance of its Applicable Certificate or a beneficial interest therein, agrees to treat the Applicable Trust as a grantor trust for all U.S. federal, state and local income tax purposes. The powers granted and obligations undertaken pursuant to the Agreement shall be so construed so as to further such intent.

IN WITNESS WHEREOF, the Company and the Trustee have caused this Trust Supplement to be duly executed by their respective officers thereto duly authorized, as of the day and year first written above.

Signature Page to Class A-O Trust Supplement 19-1

A-1

EXHIBIT A

FORM OF CERTIFICATE

Certificate

No.             

[Unless this certificate is presented by an authorized representative of The Depository Trust Company, a New York corporation (“DTC”), to Issuer or its agent for registration of transfer, exchange or payment, and any certificate issued is registered in the name of Cede & Co. or in such other name as is requested by an authorized representative of DTC (and any payment is made to Cede & Co. or to such other entity as is requested by an authorized representative of DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL inasmuch the registered owner hereof, Cede & Co., has an interest herein.]^*

UNITED AIRLINES PASS THROUGH TRUST 2019-1A-O

United Airlines Pass Through Certificate, Series 2019-1A-O

Issuance Date: February 11, 2019

Final Maturity Date: February 25, 2033

Evidencing A Fractional Undivided Interest In The United Airlines Pass Through Trust 2019-1A-O The Property Of Which Shall Include Certain Equipment Notes Each Secured By An Aircraft Owned By United Airlines, Inc.

$[                                 ] Fractional Undivided Interest

representing 0.000337331% of the Trust per $1,000 face amount

THIS CERTIFIES THAT                         , for value received, is the registered owner of a $                         (                                                                                                       DOLLARS) Fractional Undivided Interest in the United Airlines Pass Through Trust 2019-1A-O (the “Trust”) created by Wilmington Trust, National Association, as trustee (the “Trustee”), pursuant to a Pass Through Trust Agreement, dated as of October 3, 2012 (the “Basic Agreement”), between the Trustee and United Airlines, Inc. (formerly known as Continental Airlines, Inc.), a Delaware corporation (the “Company”), as supplemented by Trust Supplement No. 2019-1A-O thereto, dated as of February 11, 2019 (the “Trust Supplement” and, together

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with the Basic Agreement, the “Agreement”), between the Trustee and the Company, a summary of certain of the pertinent provisions of which is set forth below. To the extent not otherwise defined herein, the capitalized terms used herein have the meanings assigned to them in the Agreement. This Certificate is one of the duly authorized Certificates designated as “United Airlines Pass Through Certificates, Series 2019-1A-O” (herein called the “Certificates”). This Certificate is issued under and is subject to the terms, provisions and conditions of the Agreement. By virtue of its acceptance hereof, the holder of this Certificate (the “Certificateholder” and, together with all other holders of Certificates issued by the Trust, the “Certificateholders”) assents to and agrees to be bound by the provisions of the Agreement and the Intercreditor Agreement. The property of the Trust includes certain Equipment Notes and all rights of the Trust to receive payments under the Intercreditor Agreement and the Liquidity Facility (the “Trust Property”). Each issue of the Equipment Notes is secured by, among other things, a security interest in an Aircraft owned by the Company.

The Certificates represent Fractional Undivided Interests in the Trust and the Trust Property and have no rights, benefits or interest in respect of any other separate trust established pursuant to the terms of the Basic Agreement for any other series of certificates issued pursuant thereto.

Subject to and in accordance with the terms of the Agreement and the Intercreditor Agreement, from funds then available to the Trustee, there will be distributed on February 25 and August 25 of each year (a “Regular Distribution Date”) commencing August 25, 2019, to the Person in whose name this Certificate is registered at the close of business on the 15th day preceding the Regular Distribution Date, an amount in respect of the Scheduled Payments on the Equipment Notes due on such Regular Distribution Date, the receipt of which has been confirmed by the Trustee, equal to the product of the percentage interest in the Trust evidenced by this Certificate and an amount equal to the sum of such Scheduled Payments. Subject to and in accordance with the terms of the Agreement and the Intercreditor Agreement, in the event that Special Payments on the Equipment Notes are received by the Trustee, from funds then available to the Trustee, there shall be distributed on the applicable Special Distribution Date, to the Person in whose name this Certificate is registered at the close of business on the 15th day preceding the Special Distribution Date, an amount in respect of such Special Payments on the Equipment Notes, the receipt of which has been confirmed by the Trustee, equal to the product of the percentage interest in the Trust evidenced by this Certificate and an amount equal to the sum of such Special Payments so received. If a Regular Distribution Date or Special Distribution Date is not a Business Day, distribution shall be made on the immediately following Business Day with the same force and effect as if made on such Regular Distribution Date or Special Distribution Date and no interest shall accrue during the intervening period. The Trustee shall mail notice of each Special Payment and the Special Distribution Date therefor to the Certificateholder of this Certificate.

Distributions on this Certificate will be made by the Trustee by check mailed to the Person entitled thereto, without presentation or surrender of this Certificate or the making of any notation hereon, except that with respect to Certificates registered on the Record Date in the name of a Clearing Agency (or its nominee) such distribution shall be made by wire transfer. Except as otherwise provided in the Agreement and notwithstanding the above, the final distribution on this Certificate will be made after notice mailed by the Trustee of the pendency of such distribution and only upon presentation and surrender of this Certificate at the office or agency of the Trustee specified in such notice.

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The Certificates do not represent a direct obligation of, or an obligation guaranteed by, or an interest in, the Company or the Trustee or any affiliate thereof. The Certificates are limited in right of payment, all as more specifically set forth on the face hereof and in the Agreement. All payments or distributions made to Certificateholders under the Agreement shall be made only from the Trust Property and only to the extent that the Trustee shall have sufficient income or proceeds from the Trust Property to make such payments in accordance with the terms of the Agreement. Each Certificateholder of this Certificate, by its acceptance hereof, agrees that it will look solely to the income and proceeds from the Trust Property to the extent available for distribution to such Certificateholder as provided in the Agreement. This Certificate does not purport to summarize the Agreement and reference is made to the Agreement for information with respect to the interests, rights, benefits, obligations, privileges, and duties evidenced hereby. A copy of the Agreement may be examined during normal business hours at the principal office of the Trustee, and at such other places, if any, designated by the Trustee, by any Certificateholder upon request.

The Agreement permits, with certain exceptions therein provided, the amendment thereof and the modification of the rights and obligations of the Company and the rights of the Certificateholders under the Agreement at any time by the Company and the Trustee with the consent of the Certificateholders holding Certificates evidencing Fractional Undivided Interests aggregating not less than a majority in interest in the Trust. Any such consent by the Certificateholder of this Certificate shall be conclusive and binding on such Certificateholder and upon all future Certificateholders of this Certificate and of any Certificate issued upon the transfer hereof or in exchange hereof or in lieu hereof whether or not notation of such consent is made upon this Certificate. The Agreement also permits the amendment thereof, in certain limited circumstances, without the consent of the Certificateholders of any of the Certificates.

As provided in the Agreement and subject to certain limitations set forth therein, the transfer of this Certificate is registrable in the Register upon surrender of this Certificate for registration of transfer at the offices or agencies maintained by the Trustee in its capacity as Registrar, or by any successor Registrar, duly endorsed or accompanied by a written instrument of transfer in form satisfactory to the Trustee and the Registrar, duly executed by the Certificateholder hereof or such Certificateholder’s attorney duly authorized in writing, and thereupon one or more new Certificates of authorized denominations evidencing the same aggregate Fractional Undivided Interest in the Trust will be issued to the designated transferee or transferees.

Under certain circumstances set forth in Section 7.01 of the Trust Supplement, all of the Trustee’s right, title and interest to the Trust Property may be assigned, transferred and delivered to the Related Trustee of the Related Trust pursuant to the Assignment and Assumption Agreement. Upon the effectiveness of such Assignment and Assumption Agreement (the “Transfer”), the Trust shall be terminated, the Certificateholders shall receive beneficial interests in the Related Trust in exchange for their interests in the Trust equal to their respective beneficial

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interests in the Trust, the Certificates representing Fractional Undivided Interests in the Trust shall be deemed for all purposes of the Agreement and the Related Pass Through Trust Agreement to be certificates representing the same Fractional Undivided Interests in the Related Trust and its trust property. Each Certificateholder, by its acceptance of this Certificate or a beneficial interest herein, agrees to be bound by the Assignment and Assumption Agreement and subject to the terms of the Related Pass Through Trust Agreement as a Certificateholder thereunder. From and after the Transfer, unless and to the extent the context otherwise requires, references herein to the Trust, the Agreement and the Trustee shall constitute references to the Related Trust, the Related Pass Through Trust Agreement and trustee of the Related Trust, respectively.

The Certificates are issuable only as registered Certificates without coupons in minimum denominations of $1,000 Fractional Undivided Interest and integral multiples thereof, except that one Certificate may be issued in a different denomination. As provided in the Agreement and subject to certain limitations therein set forth, the Certificates are exchangeable for new Certificates of authorized denominations evidencing the same aggregate Fractional Undivided Interest in the Trust, as requested by the Certificateholder surrendering the same.

No service charge will be made for any such registration of transfer or exchange, but the Trustee shall require payment of a sum sufficient to cover any tax or governmental charge payable in connection therewith.

Each Certificateholder and Investor, by its acceptance of this Certificate or a beneficial interest herein, agrees to treat the Trust as a grantor trust for all U.S. federal, state and local income tax purposes.

The Trustee, the Registrar, and any agent of the Trustee or the Registrar may treat the person in whose name this Certificate is registered as the owner hereof for all purposes, and neither the Trustee, the Registrar, nor any such agent shall be affected by any notice to the contrary.

The obligations and responsibilities created by the Agreement and the Trust created thereby shall terminate upon the distribution to Certificateholders of all amounts required to be distributed to them pursuant to the Agreement and the disposition of all property held as part of the Trust Property.

Any Person acquiring or accepting this Certificate or an interest herein will, by such acquisition or acceptance, be deemed to have represented and warranted to and for the benefit of the Company that either: (i) no assets of an employee benefit plan subject to Title I of the Employee Retirement Income Security Act of 1974, as amended (“ERISA”), a plan subject to Section 4975 of the Internal Revenue Code of 1986, as amended (the “Code”), or a governmental, church or foreign plan subject to a law that is similar to Title I of ERISA or Section 4975 of the Code (a “Similar Law Plan”) have been used to purchase or hold this Certificate or an interest herein or (ii) the purchase and holding of this Certificate or an interest herein either (a) in the case of assets of an employee benefit plan subject to Title I of ERISA or a plan subject to Section 4975 of the Code, are exempt from the prohibited transaction restrictions of ERISA and the Code pursuant to one or more prohibited transaction statutory or administrative exemptions or (b) in the case of assets of a Similar Law Plan, will not violate any similar state, local or foreign law.

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If the purchaser or transferee of this Certificate or an interest herein is an employee benefit plan subject to Title I of ERISA or a plan subject to Section 4975 of the Code, it will be deemed to represent, warrant and agree that (i) none of United Continental Holdings, Inc., the Company, or the Underwriters, nor any of their affiliates, has provided any investment recommendation or investment advice on which it, or any fiduciary or other person investing the assets of such plan (“Plan Fiduciary”), has relied in connection with its decision to invest in this Certificate, and they are not otherwise acting as a fiduciary, as defined in Section 3(21) of ERISA or Section 4975(e)(3) of the Code, to such plan or the Plan Fiduciary in connection with such plan’s acquisition of this Certificate; and (ii) the Plan Fiduciary is exercising its own independent judgment in evaluating the transaction.

THE AGREEMENT AND, UNTIL THE TRANSFER, THIS CERTIFICATE SHALL BE GOVERNED BY AND CONSTRUED IN ACCORDANCE WITH THE LAWS OF THE STATE OF DELAWARE AND THE OBLIGATIONS, RIGHTS AND REMEDIES OF THE PARTIES HEREUNDER SHALL BE DETERMINED IN ACCORDANCE WITH SUCH LAWS. THE RELATED PASS THROUGH TRUST AGREEMENT AND, FROM AND AFTER THE TRANSFER, THIS CERTIFICATE SHALL BE GOVERNED AND CONSTRUED IN ACCORDANCE WITH THE LAWS OF THE STATE OF NEW YORK AND THE OBLIGATIONS, RIGHTS AND REMEDIES OF THE PARTIES HEREUNDER SHALL BE DETERMINED IN ACCORDANCE WITH SUCH LAWS.

Unless the certificate of authentication hereon has been executed by the Trustee, by manual signature, this Certificate shall not be entitled to any benefit under the Agreement or be valid for any purpose.

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IN WITNESS WHEREOF, the Trustee has caused this Certificate to be duly executed.

FORM OF THE TRUSTEE’S CERTIFICATE OF AUTHENTICATION

This is one of the Certificates referred to in the within-mentioned Agreement.

EXHIBIT B

[DTC Letter of Representations]

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EXHIBIT C

FORM OF ASSIGNMENT AND ASSUMPTION AGREEMENT

United Airlines Pass Through Trust 2019-1A-O

ASSIGNMENT AND ASSUMPTION AGREEMENT (2019-1A-O), dated                            ,          (the “Assignment Agreement”), between Wilmington Trust, National Association, a national banking association (“WTNA”), not in its individual capacity except as expressly provided herein, but solely as trustee under the Pass Through Trust Agreement dated as of October 3, 2012 (as amended or modified from time to time, the “Basic Agreement”), as supplemented by the Trust Supplement No. 2019-1A-O dated as of February 11, 2019 (the “Trust Supplement” and together with the Basic Agreement, the “Agreement”) in respect of the United Airlines Pass Through Trust 2019-1A-O (the “Assignor”), and Wilmington Trust, National Association, a national banking association, not in its individual capacity except as expressly provided herein, but solely as trustee under the Basic Agreement as supplemented by the Trust Supplement No. 2019-1A-S dated as of February 11, 2019 (the “New Supplement”, and, together with the Basic Agreement, the “New Agreement”) in respect of the United Airlines Pass Through Trust 2019-1A-S (the “Assignee”).

W I T N E S S E T H:

WHEREAS, the parties hereto desire to effect on the date hereof (the “Transfer Date”) (a) the transfer by the Assignor to the Assignee of all of the right, title and interest of the Assignor in, under and with respect to, among other things, the Trust Property and each of the documents listed in Schedule I hereto (the “Scheduled Documents”) and (b) the assumption by the Assignee of the obligations of the Assignor (i) under the Scheduled Documents and (ii) in respect of the Applicable Certificates issued under the Agreement; and

WHEREAS, the Scheduled Documents permit such transfer upon satisfaction of certain conditions heretofore or concurrently herewith being complied with;

NOW, THEREFORE, in consideration of the premises and of the mutual covenants and agreements herein contained, the parties hereto do hereby agree as follows (capitalized terms used herein without definition having the meaning ascribed thereto in the Agreement):

1.    Assignment. The Assignor does hereby sell, assign, convey, transfer and set over unto the Assignee as of the Transfer Date all of its present and future right, title and interest in, under and with respect to the Trust Property and the Scheduled Documents and each other contract, agreement, document or instrument relating to the Trust Property or the Scheduled Documents (such other contracts, agreements, documents or instruments, together with the Scheduled Documents, to be referred to as the “Assigned Documents”), and any proceeds therefrom, together with all documents and instruments evidencing any of such right, title and interest.

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2.    Assumption. The Assignee hereby assumes for the benefit of the Assignor and each of the parties listed in Schedule II hereto (collectively, the “Beneficiaries”) all of the duties and obligations of the Assignor, whenever accrued, pursuant to the Assigned Documents and hereby confirms that it shall be deemed a party to each of the Assigned Documents to which the Assignor is a party and shall be bound by all the terms thereof (including the agreements and obligations of the Assignor set forth therein) as if therein named as the Assignor. Further, the Assignee hereby assumes for the benefit of the Assignor and the Beneficiaries all of the duties and obligations of the Assignor under the Outstanding Applicable Certificates and hereby confirms that the Applicable Certificates representing Fractional Undivided Interests under the Agreement shall be deemed for all purposes of the Agreement and the New Agreement to be certificates representing the same Fractional Undivided Interests under the New Agreement equal to their respective beneficial interests in the trust created under the Agreement.

3.    Effectiveness. This Assignment Agreement shall be effective upon the execution and delivery hereof by the parties hereto, and each Applicable Certificateholder, by its acceptance of its Applicable Certificate or a beneficial interest therein, agrees to be bound by the terms of this Assignment Agreement.

4.    Payments. The Assignor hereby covenants and agrees to pay over to the Assignee, if and when received following the Transfer Date, any amounts (including any sums payable as interest in respect thereof) paid to or for the benefit of the Assignor that, under Section 1 hereof, belong to the Assignee.

5.    Further Assurances. The Assignor shall, at any time and from time to time, upon the request of the Assignee, promptly and duly execute and deliver any and all such further instruments and documents and take such further action as the Assignee may reasonably request to obtain the full benefits of this Assignment Agreement and of the rights and powers herein granted. The Assignor agrees to deliver any Applicable Certificates, and all Trust Property, if any, then in the physical possession of the Assignor, to the Assignee.

6.    Representations and Warranties. (a) The Assignee represents and warrants to the Assignor and each of the Beneficiaries that:

(i)    it has all requisite power and authority and legal right to enter into and carry out the transactions contemplated hereby and to carry out and perform the obligations of the “Pass Through Trustee” under the Assigned Documents;

(ii)    on and as of the date hereof, the representations and warranties of the Assignee set forth in Section 7.15 of the Basic Agreement and Section 5.04 of the New Supplement are true and correct.

(b)    The Assignor represents and warrants to the Assignee that:

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(i)    it is duly incorporated, validly existing and in good standing under the laws of the United States and has the full trust power, authority and legal right under the laws of the United States and of the state of the United States in which it is located pertaining to its trust and fiduciary powers to execute and deliver this Assignment Agreement;

(ii)    the execution and delivery by it of this Assignment Agreement and the performance by it of its obligations hereunder have been duly authorized by it and will not violate its articles of association or by-laws or the provisions of any indenture, mortgage, contract or other agreement to which it is a party or by which it is bound; and

(iii)    this Assignment Agreement constitutes the legal, valid and binding obligations of it enforceable against it in accordance with its terms, except as the same may be limited by applicable bankruptcy, insolvency, reorganization, moratorium or similar laws affecting the rights of creditors generally and by general principles of equity, whether considered in a proceeding at law or in equity.

7.    GOVERNING LAW. THIS ASSIGNMENT AGREEMENT SHALL BE GOVERNED BY AND CONSTRUED IN ACCORDANCE WITH THE LAWS OF THE STATE OF NEW YORK INCLUDING MATTERS OF CONSTRUCTION, VALIDITY AND PERFORMANCE.

8.    Counterparts. This Assignment Agreement may be executed in any number of counterparts, all of which together shall constitute a single instrument. It shall not be necessary that any counterpart be signed by both parties so long as each party shall sign at least one counterpart.

9.    Third Party Beneficiaries. The Assignee hereby agrees, for the benefit of the Beneficiaries, that its representations, warranties and covenants contained herein are also intended to be for the benefit of each Beneficiary, and each Beneficiary shall be deemed to be an express third party beneficiary with respect thereto, entitled to enforce directly and in its own name any rights or claims it may have against such party as such beneficiary.

10.     Notice. Promptly following the Transfer Date, the Assignee shall notify the Depositary of the occurrence of the assignment hereunder and the name and contact information of the Assignee.

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IN WITNESS WHEREOF, the parties hereto, through their respective officers thereunto duly authorized, have duly executed this Assignment Agreement as of the day and year first above written.

Schedule I

Schedule of Assigned Documents

(1) Intercreditor Agreement dated as of February 11, 2019 among the Trustee, the Other Trustees party thereto, the Liquidity Provider and the Subordination Agent.

(2) Escrow and Paying Agent Agreement (Class A) dated as of February 11, 2019 among the Escrow Agent, the Underwriters, the Trustee and the Escrow Paying Agent.

(3) Note Purchase Agreement dated as of February 11, 2019 among the Company, the Trustee, the Other Trustees party thereto, the Subordination Agent, the Escrow Agent and the Escrow Paying Agent.

(4) Deposit Agreement (Class A) dated as of February 11, 2019 between the Escrow Agent and the Depositary.

(5) Each of the Operative Agreements (as defined in the Participation Agreement for each Aircraft) in effect as of the Transfer Date.

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Schedule II

Schedule of Beneficiaries

Wilmington Trust, National Association, not in its individual capacity but solely as Subordination Agent

Wilmington Trust, National Association, not in its individual capacity but solely as Paying Agent

National Australia Bank Limited, acting through its New York Branch, as Liquidity Provider

Sumitomo Mitsui Banking Corporation, acting through its New York Branch, as Depositary

United Airlines, Inc.

Citigroup Global Markets Inc., as Underwriter

Credit Suisse Securities (USA) LLC, as Underwriter

Goldman Sachs & Co. LLC, as Underwriter

Deutsche Bank Securities Inc., as Underwriter

Morgan Stanley & Co. LLC, as Underwriter

J.P. Morgan Securities LLC, as Underwriter

Barclays Capital Inc., as Underwriter

Merrill Lynch, Pierce, Fenner & Smith Incorporated, as Underwriter

BBVA Securities Inc., as Underwriter

BNP Paribas Securities Corp., as Underwriter

Credit Agricole Securities (USA) Inc., as Underwriter

Standard Chartered Bank, as Underwriter

Wells Fargo Securities, LLC., as Underwriter

U.S. Bank National Association, as Escrow Agent

Each of the other parties to the Assigned Documents

Exhibit 4.4

EXECUTION VERSION

TRUST SUPPLEMENT No. 2019-1A-S

Dated as of February 11, 2019

between

WILMINGTON TRUST, NATIONAL ASSOCIATION

as Trustee,

and

UNITED AIRLINES, INC.

to

PASS THROUGH TRUST AGREEMENT

Dated as of October 3, 2012

$296,445,000

United Airlines Pass Through Trust 2019-1A-S

4.55% United Airlines Pass Through Certificates, Series 2019-1A-S

TABLE OF CONTENTS

Page

This Trust Supplement No. 2019-1A-S, dated as of February 11, 2019 (herein called the “Trust Supplement”), between United Airlines, Inc., a Delaware corporation (the “Company”), and Wilmington Trust, National Association (the “Trustee”), to the Pass Through Trust Agreement, dated as of October 3, 2012, between the Company (formerly known as Continental Airlines, Inc.) and the Trustee (the “Basic Agreement”).

W I T N E S S E T H:

WHEREAS, the Basic Agreement, unlimited as to the aggregate face amount of Certificates (unless otherwise specified herein, capitalized terms used herein without definition having the respective meanings specified in the Basic Agreement) which may be issued thereunder, has heretofore been executed and delivered;

WHEREAS, the Company is the owner of or has obtained commitments from Boeing for the delivery of nine Boeing 737 MAX 9 aircraft, six Boeing 787-10 aircraft and ten Embraer ERJ 175 LL aircraft (collectively, the “Applicable Aircraft”);

WHEREAS, as of the Transfer Date, the Company will have financed the Applicable Aircraft;

WHEREAS, as of the Transfer Date, with respect to each Applicable Aircraft, the Company will have issued pursuant to an Indenture, on a recourse basis, Equipment Notes to finance a portion of the purchase price of such Applicable Aircraft;

WHEREAS, as of the Transfer Date, the Related Trustee will assign, transfer and deliver all of such trustee’s right, title and interest to the trust property held by the Related Trustee to the Trustee pursuant to the Assignment and Assumption Agreement;

WHEREAS, the Trustee, effective only, but automatically, upon execution and delivery of the Assignment and Assumption Agreement, will be deemed to have declared the creation of the United Airlines Pass Through Trust 2019-1A-S (the “Applicable Trust”) for the benefit of the Applicable Certificateholders, and each Holder of Applicable Certificates “Outstanding” as of the Transfer Date, as the grantors of the Applicable Trust, by their respective acceptances of such Applicable Certificates (as defined below), will join in the creation of the Applicable Trust with the Trustee;

WHEREAS, all Applicable Certificates to be deemed issued by the Applicable Trust will evidence Fractional Undivided Interests in the Applicable Trust and will convey no rights, benefits or interests in respect of any property other than the Trust Property except for those Applicable Certificates to which an Escrow Receipt (as defined below) has been affixed;

WHEREAS, upon the execution and delivery of the Assignment and Assumption Agreement, all of the conditions and requirements necessary to make this Trust Supplement, when duly executed and delivered, a valid, binding and legal instrument in accordance with its terms and for the purposes herein expressed, have been done, performed and fulfilled, and the execution and delivery of this Trust Supplement in the form and with the terms hereof have been in all respects duly authorized; and

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WHEREAS, this Trust Supplement is subject to the provisions of the Trust Indenture Act of 1939, as amended, and shall, to the extent applicable, be governed by such provisions.

NOW THEREFORE, in consideration of the premises herein, it is agreed between the Company and the Trustee as follows:

ARTICLE I

THE CERTIFICATES

Section 1.01. The Certificates. The Applicable Certificates shall be known as “United Airlines Pass Through Certificates, Series 2019-1A-S”. Each Applicable Certificate represents a Fractional Undivided Interest in the Applicable Trust created hereby. The Applicable Certificates shall be the only instruments evidencing a Fractional Undivided Interest in the Applicable Trust.

The terms and conditions applicable to the Applicable Certificates are as follows:

(a)    The aggregate face amount of the Applicable Certificates that shall be initially deemed issued under the Agreement shall be equal to the aggregate principal amount of “Outstanding” pass through certificates representing Fractional Undivided Interests in the Related Trust on the Transfer Date. Subject to the preceding sentence and Section 5.01 of this Trust Supplement and except for Applicable Certificates authenticated and delivered under Sections 3.03, 3.04, 3.05 and 3.06 of the Basic Agreement, no Applicable Certificates shall be authenticated under the Agreement.

(b)    The Regular Distribution Dates with respect to any distribution of Scheduled Payments means February 25 and August 25 of each year, commencing on August 25, 2019 until distribution of all of the Scheduled Payments to be made under the Equipment Notes has been made.

(c)    The Special Distribution Dates with respect to the Applicable Certificates means any Business Day on which a Special Payment is to be distributed pursuant to the Agreement.

(d)    At the Escrow Agent’s request under the Escrow Agreement, the Trustee shall affix the corresponding Escrow Receipt to each Applicable Certificate. In any event, any transfer or exchange of any Applicable Certificate shall also effect a transfer or exchange of the related Escrow Receipt. Prior to the Final Distribution, no transfer or exchange of any Applicable Certificate shall be permitted unless the corresponding Escrow Receipt is attached thereto and also is so transferred or exchanged. By acceptance of any Applicable Certificate to which an Escrow Receipt is attached, each Holder of such an Applicable Certificate acknowledges and accepts the restrictions on transfer of the Escrow Receipt set forth herein and in the Escrow Agreement.

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(e)    (i)     The Applicable Certificates shall be in the form attached as Exhibit A to the Related Pass Through Trust Supplement, with such appropriate insertions, omissions, substitutions and other variations as are required or permitted by the Related Pass Through Trust Agreement or the Agreement, as the case may be, or as the Trustee may deem appropriate, to reflect the fact that the Applicable Certificates are being issued under the Agreement as opposed to under the Related Pass Through Trust Agreement. Any Person acquiring or accepting an Applicable Certificate or an interest therein will, by such acquisition or acceptance, be deemed to have represented and warranted to and for the benefit of the Company that either (x) no assets of an employee benefit plan subject to Title I of the Employee Retirement Income Security Act of 1974, as amended (“ERISA”), a plan subject to Section 4975 of the Internal Revenue Code of 1986, as amended (the “Code”), or a governmental, church or foreign plan subject to a law that is similar to Title I of ERISA or Section 4975 of the Code (a “Similar Law Plan”) have been used to purchase or hold such Applicable Certificate or an interest therein or (y) the purchase and holding of such Applicable Certificate or an interest therein either (A) in the case of assets of an employee benefit plan subject to Title I of ERISA or a plan subject to Section 4975 of the Code, are exempt from the prohibited transaction restrictions of ERISA and the Code pursuant to one or more prohibited transaction statutory or administrative exemptions or (B) in the case of assets of a Similar Law Plan, will not violate any similar state, local or foreign law.

(ii)    The Applicable Certificates shall be Book-Entry Certificates and shall be subject to the conditions set forth in the Letter of Representations between the Applicable Trust and the Clearing Agency attached as Exhibit B to the Related Pass Through Trust Supplement.

(f)    If the purchaser or transferee of an Applicable Certificate or an interest therein is an employee benefit plan subject to Title I of ERISA or a plan subject to Section 4975 of the Code, it will be deemed to represent, warrant and agree that (i) none of United Continental Holdings, Inc., the Company, or the Underwriters, nor any of their affiliates, has provided any investment recommendation or investment advice on which it, or any fiduciary or other person investing the assets of such plan (“Plan Fiduciary”), has relied in connection with its decision to invest in the Applicable Certificates, and they are not otherwise acting as a fiduciary, as defined in Section 3(21) of ERISA or Section 4975(e)(3) of the Code, to such plan or the Plan Fiduciary in connection with such plan’s acquisition of the Applicable Certificates; and (ii) the Plan Fiduciary is exercising its own independent judgment in evaluating the transaction.

(g)    The “Participation Agreements” as defined in this Trust Supplement are the “Note Purchase Agreements” referred to in the Basic Agreement.

(h)    The Applicable Certificates are subject to the Intercreditor Agreement, the Deposit Agreement and the Escrow Agreement.

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(i)    The Applicable Certificates are entitled to the benefits of the Liquidity Facility.

(j)    The Responsible Party is the Company.

(k)    The date referred to in clause (i) of the definition of the term “PTC Event of Default” in the Basic Agreement is the Final Maturity Date.

(l)    The “particular sections of the Note Purchase Agreement”, for purposes of clause (3) of Section 7.07 of the Basic Agreement, are Section 8.1 of each Participation Agreement.

(m)    The Equipment Notes to be acquired and held in the Applicable Trust, and the related Aircraft and Note Documents, are described in the NPA.

ARTICLE II

DEFINITIONS

Section 2.01. Definitions. For all purposes of the Basic Agreement as supplemented by this Trust Supplement, the following capitalized terms have the following meanings (any term used herein which is defined in both this Trust Supplement and the Basic Agreement shall have the meaning assigned thereto in this Trust Supplement for purposes of the Basic Agreement as supplemented by this Trust Supplement):

Agreement: Means the Basic Agreement, as supplemented by this Trust Supplement.

Aircraft: Means each of the Applicable Aircraft (or Substitute Aircraft) in respect of which a Participation Agreement is to be or is entered into in accordance with the NPA (or any Substitute Aircraft, including engines therefor, owned by the Company and securing one or more Equipment Notes).

Aircraft Purchase Agreement: Has the meaning specified in the NPA.

Applicable Aircraft: Has the meaning specified in the recitals hereto.

Applicable Certificate: Means any of the “Applicable Certificates” issued by the Related Trust and that are “Outstanding” (as defined in the Related Pass Through Trust Agreement) as of the Transfer Date (the “Transfer Date Certificates”) and any Certificate issued in exchange therefor or replacement thereof pursuant to the Agreement.

Applicable Certificateholder: Means the Person in whose name an Applicable Certificate is registered on the Register for the Applicable Certificates.

Applicable Trust: Has the meaning specified in the recitals hereto.

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Assignment and Assumption Agreement: Means the assignment and assumption agreement substantially in the form of Exhibit C to the Related Pass Through Trust Supplement executed and delivered in accordance with Section 7.01 of the Related Pass Through Trust Supplement.

Basic Agreement: Has the meaning specified in the first paragraph of this Trust Supplement.

Boeing: Means The Boeing Company.

Business Day: Means any day other than a Saturday, a Sunday or a day on which commercial banks are required or authorized to close in New York, New York, Chicago, Illinois, or, so long as any Applicable Certificate is Outstanding, the city and state in which the Trustee, the Subordination Agent or any Loan Trustee maintains its Corporate Trust Office or receives and disburses funds.

Certificate: Has the meaning specified in the Intercreditor Agreement.

Certificate Buyout Event: Means that a United Bankruptcy Event has occurred and is continuing and either of the following events has occurred: (A) both (i) the 60-day period specified in Section 1110(a)(2)(A) of the U.S. Bankruptcy Code (the “60-Day Period”) has expired and (ii) the Company has not entered into one or more agreements under Section 1110(a)(2)(A) of the U.S. Bankruptcy Code to perform all of its obligations under all of the Indentures or, if it has entered into such agreements, has at any time thereafter failed to cure any default under any of the Indentures in accordance with Section 1110(a)(2)(B) of the U.S. Bankruptcy Code; or (B) prior to the expiry of the 60-Day Period, the Company shall have abandoned any Aircraft.

Class: Has the meaning specified in the Intercreditor Agreement.

Closing Notice: Has the meaning specified in the NPA.

Company: Has the meaning specified in the first paragraph of this Trust Supplement.

Controlling Party: Has the meaning specified in the Intercreditor Agreement.

Cut-off Date: Means the earlier of (a) the Delivery Period Termination Date and (b) the date on which a Triggering Event occurs.

Delivery Period Termination Date: Has the meaning specified in the Related Pass Through Trust Supplement.

Deposit Agreement: Means the Deposit Agreement dated as of February 11, 2019 relating to the Applicable Certificates between the Depositary and the Escrow Agent, as the same may be amended, supplemented or otherwise modified from time to time in accordance with its terms.

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Depositary: Means Sumitomo Mitsui Banking Corporation, acting through its New York Branch.

Deposits: Has the meaning specified in the Deposit Agreement.

Distribution Date: Means any Regular Distribution Date or Special Distribution Date as the context requires.

ERISA: Has the meaning specified in Section 1.01(e) of this Trust Supplement.

Escrow Agent: Means, initially, U.S. Bank National Association and any replacement or successor therefor appointed in accordance with the Escrow Agreement.

Escrow Agreement: Means the Escrow and Paying Agent Agreement dated as of February 11, 2019 relating to the Applicable Certificates, among the Escrow Agent, the Escrow Paying Agent, the Related Trustee (and after the Transfer Date, the Trustee) and the Underwriters, as the same may be amended, supplemented or otherwise modified from time to time in accordance with its terms.

Escrow Paying Agent: Means the Person acting as paying agent under the Escrow Agreement.

Escrow Receipt: Means the receipt substantially in the form annexed to the Escrow Agreement representing a Fractional Undivided Interest in the funds held in escrow thereunder.

Final Distribution: Has the meaning specified in the Escrow Agreement.

Final Maturity Date: Means February 25, 2033.

Final Withdrawal: Has the meaning specified in the Escrow Agreement.

Final Withdrawal Date: Has the meaning specified in the Escrow Agreement.

Indenture: Means each of the separate trust indentures and mortgages relating to the Aircraft, each as specified or described in a Closing Notice delivered pursuant to the NPA or the related Participation Agreement, in each case as the same may be amended, supplemented or otherwise modified from time to time in accordance with its terms.

Intercreditor Agreement: Means the Intercreditor Agreement dated as of February 11, 2019 among the Related Trustee (and after the Transfer Date, the Trustee), the Related Other Trustees (and after the Transfer Date, the Other Trustees) party thereto, the Liquidity Provider, the liquidity provider relating to the Class A Certificates and Wilmington Trust, National Association, as Subordination Agent and as trustee thereunder, as amended, supplemented or otherwise modified from time to time in accordance with its terms.

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Investors: Means the Underwriters, together with all subsequent beneficial owners of the Applicable Certificates.

Liquidity Facility: Means, initially, the Revolving Credit Agreement dated as of February 11, 2019 relating to the Applicable Certificates, between the Liquidity Provider and Wilmington Trust, National Association, as Subordination Agent, as agent and trustee for the Applicable Trust, and, from and after the replacement of such agreement pursuant to the Intercreditor Agreement, the replacement liquidity facility therefor, in each case as amended, supplemented or otherwise modified from time to time in accordance with their respective terms.

Liquidity Provider: Means, initially, National Australia Bank Limited, acting through its New York Branch, and any replacements or successors therefor appointed in accordance with the Intercreditor Agreement.

Make-Whole Amount: Has the meaning specified in any Indenture.

Note Documents: Means the Equipment Notes with respect to the Applicable Certificates and, with respect to any such Equipment Note, the Indenture and the Participation Agreement relating to such Equipment Note.

NPA: Means the Note Purchase Agreement, dated as of the date hereof among the Related Trustee (and after the Transfer Date, the Trustee), the Related Other Trustees (and after the Transfer Date, the Other Trustees) party thereto, the Company, the Escrow Agent, the Escrow Paying Agent and the Subordination Agent, providing for, among other things, the purchase of Equipment Notes by the Trustee on behalf of the Applicable Trust, as the same may be amended, supplemented or otherwise modified from time to time, in accordance with its terms.

Other Agreements: Means (i) the Basic Agreement, as supplemented by Trust Supplement No. 2019-1AA-S dated as of the date hereof relating to United Airlines Pass Through Trust 2019-1AA-S, (ii) the Basic Agreement as supplemented by a Trust Supplement relating to any Additional Trust and (iii) the Basic Agreement as supplemented by a Trust Supplement relating to any Refinancing Trust.

Other Trustees: Means the trustees under the Other Agreements, and any successor or other trustee appointed as provided therein.

Other Trusts: Means the United Airlines Pass Through Trust 2019-1AA-S, an Additional Trust or Trusts, if any, and a Refinancing Trust or Trusts, if any, created by the Other Agreements.

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Outstanding: When used with respect to Applicable Certificates, means, as of the date of determination, all Transfer Date Certificates, and all other Applicable Certificates theretofore authenticated and delivered under the Agreement, in each case except:

(i)    Applicable Certificates theretofore canceled by the Registrar or delivered to the Trustee or the Registrar for cancellation;

(ii)    Applicable Certificates for which money in the full amount required to make the final distribution with respect to such Applicable Certificates pursuant to Section 11.01 of the Basic Agreement has been theretofore deposited with the Trustee in trust for the Applicable Certificateholders as provided in Section 4.01 of the Basic Agreement pending distribution of such money to such Applicable Certificateholders pursuant to payment of such final distribution; and

(iii)    Applicable Certificates in exchange for or in lieu of which other Applicable Certificates have been authenticated and delivered pursuant to the Agreement.

Participation Agreement: Means each Participation Agreement entered into by the Related Trustee pursuant to the NPA, as the same may be amended, supplemented or otherwise modified in accordance with its terms.

Pool Balance: Means, as of any date, (i) the original aggregate face amount of the Applicable Certificates, less (ii) the aggregate amount of all payments made as of such date in respect of such Certificates, the Applicable Certificates or the Deposits, other than payments made in respect of interest or premium (including Make-Whole Amount) thereon or reimbursement of any costs or expenses incurred in connection therewith. The Pool Balance as of any date shall be computed after giving effect to any special distribution with respect to unused Deposits, payment of principal of the Equipment Notes, or payment with respect to other Trust Property and the distribution thereof to be made on that date.

Pool Factor: Means, as of any Distribution Date, the quotient (rounded to the seventh decimal place) computed by dividing (i) the Pool Balance by (ii) the original aggregate face amount of the Applicable Certificates. The Pool Factor as of any Distribution Date shall be computed after giving effect to any special distribution with respect to unused Deposits, payment of principal of the Equipment Notes, or payment with respect to other Trust Property and the distribution thereof to be made on that date.

Prospectus Supplement: Means the final Prospectus Supplement dated January 28, 2019 relating to the offering of the Applicable Certificates and the Class AA Certificates.

Ratings Confirmation: Has the meaning specified in the Intercreditor Agreement.

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Related Other Pass Through Trust Agreements: Means the “Other Agreements” as defined in the Related Pass Through Trust Agreement.

Related Other Trustees: Means the “Other Trustees” as defined in the Related Pass Through Trust Agreement.

Related Other Trusts: Means the “Other Trusts” as defined in the Related Pass Through Trust Agreement.

Related Pass Through Trust Agreement: Means the Basic Agreement as supplemented by the Related Pass Through Trust Supplement.

Related Pass Through Trust Supplement: Means the Trust Supplement No. 2019-1A-O dated as of the date hereof, relating to the United Airlines Pass Through Trust 2019-1A-O and entered into by the Company and the Related Trustee, as amended, supplemented or otherwise modified from time to time in accordance with its terms.

Related Trust: Means the United Airlines Pass Through Trust 2019-1A-O, formed under the Related Pass Through Trust Agreement.

Related Trustee: Means the trustee under the Related Pass Through Trust Agreement.

Scheduled Payment: Means, with respect to any Equipment Note, (i) any payment of principal or interest on such Equipment Note (other than any such payment which is not in fact received by the Trustee or the Subordination Agent within five days of the date on which such payment is scheduled to be made) or (ii) any payment of interest on the Applicable Certificates with funds drawn under the Liquidity Facility, which payment in any such case represents the installment of principal on such Equipment Note at the stated maturity of such installment, the payment of regularly scheduled interest accrued on the unpaid principal amount of such Equipment Note, or both; provided, however, that any payment of principal, premium (including Make-Whole Amount), if any, or interest resulting from the redemption or purchase of any Equipment Note shall not constitute a Scheduled Payment.

Special Payment: Means any payment (other than a Scheduled Payment) in respect of, or any proceeds of, any Equipment Note or Collateral (as defined in each Indenture).

Substitute Aircraft: Has the meaning specified in the NPA.

Transfer Date: Means the moment of execution and delivery of the Assignment and Assumption Agreement by each of the parties thereto.

Transfer Date Certificates: Has the meaning specified in the definition of “Applicable Certificates”.

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Triggering Event: Has the meaning assigned to such term in the Intercreditor Agreement.

Trust Property: Means (i) subject to the Intercreditor Agreement, the Equipment Notes held as the property of the Applicable Trust, all monies at any time paid thereon or in respect thereof and all monies due and to become due thereunder, (ii) funds from time to time deposited in the Certificate Account and the Special Payments Account and, subject to the Intercreditor Agreement, any proceeds from the sale by the Trustee pursuant to Article VI of the Basic Agreement of any Equipment Note and (iii) all rights of the Applicable Trust and the Trustee, on behalf of the Applicable Trust, under the Intercreditor Agreement, the Escrow Agreement, the NPA and the Liquidity Facility, including, without limitation, all rights to receive certain payments thereunder, and all monies paid to the Trustee on behalf of the Applicable Trust pursuant to the Intercreditor Agreement or the Liquidity Facility, provided that rights with respect to the Deposits or under the Escrow Agreement will not constitute Trust Property.

Trust Supplement: Has the meaning specified in the first paragraph of this trust supplement.

Trustee: Has the meaning specified in the first paragraph of this Trust Supplement.

Underwriters: Means, collectively, Citigroup Global Markets Inc., Credit Suisse Securities (USA) LLC, Goldman Sachs & Co. LLC, Deutsche Bank Securities Inc., Morgan Stanley & Co. LLC, J.P. Morgan Securities LLC, Barclays Capital Inc., Merrill Lynch, Pierce, Fenner & Smith Incorporated, BBVA Securities Inc., BNP Paribas Securities Corp., Credit Agricole Securities (USA) Inc., Standard Chartered Bank and Wells Fargo Securities, LLC.

Underwriting Agreement: Means the Underwriting Agreement related to the Applicable Certificates dated January 28, 2019 among Citigroup Global Markets Inc. and Credit Suisse Securities (USA) LLC, as representatives of the several Underwriters, the Company and the Depositary, as the same may be amended, supplemented or otherwise modified from time to time in accordance with its terms.

United Bankruptcy Event: Has the meaning specified in the Intercreditor Agreement.

ARTICLE III

DISTRIBUTIONS; STATEMENTS TO CERTIFICATEHOLDERS

Section 3.01. Statements to Applicable Certificateholders. (a) On each Distribution Date, the Trustee will include with each distribution to Applicable Certificateholders of a Scheduled Payment or Special Payment, as the case may be, a statement setting forth the information provided below (in the case of a Special Payment, reflecting in part the information provided by the Escrow Paying Agent under the Escrow Agreement). Such statement shall set forth (per $1,000 face amount Applicable Certificate as to (ii), (iii), (iv) and (v) below) the following information:

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(i)    The aggregate amount of funds distributed on such Distribution Date under the Agreement and under the Escrow Agreement, indicating the amount allocable to each source, including any portion thereof paid by the Liquidity Provider;

(ii)    The amount of such distribution under the Agreement allocable to principal and the amount allocable to premium (including Make-Whole Amount), if any;

(iii)    The amount of such distribution under the Agreement allocable to interest;

(iv)    The amount of such distribution under the Escrow Agreement allocable to interest;

(v)    The amount of such distribution under the Escrow Agreement allocable to unused Deposits, if any; and

(vi)    The Pool Balance and the Pool Factor.

With respect to the Applicable Certificates registered in the name of a Clearing Agency or its nominee, on the Record Date prior to each Distribution Date, the Trustee will request that such Clearing Agency post on its Internet bulletin board a securities position listing setting forth the names of all Clearing Agency Participants reflected on such Clearing Agency’s books as holding interests in the Applicable Certificates on such Record Date. On each Distribution Date, the Trustee will mail to each such Clearing Agency Participant the statement described above and will make available additional copies as requested by such Clearing Agency Participant for forwarding to holders of interests in the Applicable Certificates.

(b)    Within a reasonable period of time after the end of each calendar year but not later than the latest date permitted by law, the Trustee shall furnish to each Person who at any time during such calendar year was an Applicable Certificateholder of record a statement containing the sum of the amounts determined pursuant to clauses (a)(i), (a)(ii), (a)(iii), (a)(iv) and (a)(v) above for such calendar year or, in the event such Person was an Applicable Certificateholder of record during a portion of such calendar year, for such portion of such year, and such other items as are readily available to the Trustee and which an Applicable Certificateholder shall reasonably request as necessary for the purpose of such Applicable Certificateholder’s preparation of its U.S. federal income tax returns. Such statement and such other items shall be prepared on the basis of information supplied to the Trustee by the Clearing Agency Participants and shall be delivered by the Trustee to such Clearing Agency Participants to be available for forwarding by such Clearing Agency Participants to the holders of interests in the Applicable Certificates in the manner described in Section 3.01(a) of this Trust Supplement.

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(c)    If the aggregate principal payments scheduled for a Regular Distribution Date prior to the Delivery Period Termination Date differ from the amount thereof set forth for the Applicable Certificates on page S-39 of the Prospectus Supplement, by no later than the 15th day prior to such Regular Distribution Date, the Trustee (if the Related Trustee has not already done so) shall mail written notice of the actual amount of such scheduled payments to the Applicable Certificateholders of record as of a date within 15 Business Days prior to the date of mailing. If the Trustee has given such notice, the Company shall not give a “Closing Notice” (as defined in the NPA) under the NPA providing for a “Funding Date” (as defined in the NPA) on or after the date the Trustee gives such notice and on or prior to such Regular Distribution Date and shall revoke any Closing Notice previously given that provides for such a Funding Date.

(d)    Promptly following (i) the Delivery Period Termination Date, if there has been any change in the information set forth in clauses (y) and (z) below from that set forth on page S-39 of the Prospectus Supplement, and (ii) the date of any early redemption of, or any default in the payment of principal or interest in respect of, any of the Equipment Notes held in the Applicable Trust, or any Final Withdrawal, the Trustee (if the Related Trustee has not already done so) shall furnish to Applicable Certificateholders of record on such date a statement setting forth (x) the expected Pool Balances for each subsequent Regular Distribution Date following the Delivery Period Termination Date, (y) the related Pool Factors for such Regular Distribution Dates and (z) the expected principal payment schedule of the Equipment Notes, in the aggregate, held as Trust Property at the date of such notice. With respect to the Applicable Certificates registered in the name of a Clearing Agency, on the Transfer Date, the Trustee (if the Related Trustee has not already done so) will request from such Clearing Agency a securities position listing setting forth the names of all Clearing Agency Participants reflected on such Clearing Agency’s books as holding interests in the Applicable Certificates on the Delivery Period Termination Date. The Trustee (if the Related Trustee has not already done so) will mail to each such Clearing Agency Participant the statement described above and will make available additional copies as requested by such Clearing Agency Participant for forwarding to holders of interests in the Applicable Certificates.

(e)    The Trustee shall provide promptly to the Applicable Certificateholders all material non-confidential information received by the Trustee from the Company.

(f)     This Section 3.01 supersedes and replaces Section 4.03 of the Basic Agreement, with respect to the Applicable Trust.

Section 3.02. Special Payments Account. (a) The Trustee shall establish and maintain on behalf of the Applicable Certificateholders a Special Payments Account as one or more accounts, which shall be non-interest bearing except as provided in Section 4.04 of the Basic Agreement. The Trustee shall hold the Special Payments Account in trust for the benefit of the Applicable Certificateholders and shall make or permit withdrawals therefrom only as provided in the Agreement. On each day when one or more Special Payments are made to the Trustee under the Intercreditor Agreement, the Trustee, upon receipt thereof, shall immediately deposit the aggregate amount of such Special Payments in the Special Payments Account.

(b)     This Section 3.02 supersedes and replaces Section 4.01(b) of the Basic Agreement in its entirety, with respect to the Applicable Trust.

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Section 3.03. Distributions from Special Payments Account. (a) On each Special Distribution Date with respect to any Special Payment or as soon thereafter as the Trustee has confirmed receipt of any Special Payments due on the Equipment Notes held (subject to the Intercreditor Agreement) in the Applicable Trust or realized upon the sale of such Equipment Notes, the Trustee shall distribute out of the Special Payments Account the entire amount of such Special Payment deposited therein pursuant to Section 3.02(a) of this Trust Supplement. There shall be so distributed to each Applicable Certificateholder of record on the Record Date with respect to such Special Distribution Date (other than as provided in Section 7.01 of this Trust Supplement concerning the final distribution) by check mailed to such Applicable Certificateholder, at the address appearing in the Register, such Applicable Certificateholder’s pro rata share (based on the Fractional Undivided Interest in the Applicable Trust held by such Applicable Certificateholder) of the total amount in the Special Payments Account on account of such Special Payment, except that, with respect to Applicable Certificates registered on the Record Date in the name of a Clearing Agency (or its nominee), such distribution shall be made by wire transfer in immediately available funds to the account designated by such Clearing Agency (or such nominee).

(b)    The Trustee shall, at the expense of the Company, cause notice of each Special Payment to be mailed to each Applicable Certificateholder at his address as it appears in the Register. In the event of redemption or purchase of Equipment Notes held in the Applicable Trust, such notice shall be mailed not less than 15 days prior to the Special Distribution Date for the Special Payment resulting from such redemption or purchase, which Special Distribution Date shall be the date of such redemption or purchase. In the case of any other Special Payments, such notice shall be mailed as soon as practicable after the Trustee has confirmed that it has received funds for such Special Payment, stating the Special Distribution Date for such Special Payment which shall occur not less than 15 days after the date of such notice and as soon as practicable thereafter. Notices with respect to a Special Payment mailed by the Trustee shall set forth:

(i)    The Special Distribution Date and the Record Date therefor (except as otherwise provided in Section 7.01 of this Trust Supplement),

(ii)    The amount of the Special Payment for each $1,000 face amount Applicable Certificate and the amount thereof constituting principal, premium (including Make-Whole Amount), if any, and interest,

(iii)    The reason for the Special Payment, and

(iv)    If the Special Distribution Date is the same date as a Regular Distribution Date, the total amount to be received on such date for each $1,000 face amount Applicable Certificate.

If the amount of premium (including Make-Whole Amount), if any, payable upon the redemption or purchase of an Equipment Note has not been calculated at the time that the Trustee mails notice of a Special Payment, it shall be sufficient if the notice sets forth the other amounts to be distributed and states that any premium (including Make-Whole Amount) received will also be distributed.

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If any redemption of the Equipment Notes held in the Applicable Trust is canceled, the Trustee, as soon as possible after learning thereof, shall cause notice thereof to be mailed to each Applicable Certificateholder at its address as it appears on the Register.

(c)    This Section 3.03 supersedes and replaces Section 4.02(b) and Section 4.02(c) of the Basic Agreement in their entirety, with respect to the Applicable Trust.

Section 3.04. Limitation of Liability for Payments. Section 3.09 of the Basic Agreement shall be amended, with respect to the Applicable Trust, by deleting the phrase “the Owner Trustees or the Owner Participants” in the second sentence thereof and adding in lieu thereof “the Liquidity Provider”.

ARTICLE IV

DEFAULT

Section 4.01. Purchase Rights of Certificateholders. (a) By acceptance of its Applicable Certificate, each Applicable Certificateholder agrees that at any time after the occurrence and during the continuation of a Certificate Buyout Event:

(i)    So long as no Additional Certificateholder has elected to exercise its rights to purchase Certificates pursuant to, and given notice of such election in accordance with, this Section 4.01(a) (upon such election and notification thereof, the right specified in this Section 4.01(a)(i) shall be suspended and (x) upon consummation of such purchase pursuant to such election, be terminated with respect to such Certificate Buyout Event, or (y) upon failure to consummate such purchase on the proposed purchase date, such right shall be reinstated), each Applicable Certificateholder (other than the Company or any of its Affiliates) shall have the right to purchase, for the purchase price set forth in the Class AA Trust Agreement, all, but not less than all, of the Class AA Certificates upon 15 days’ written notice to the Class AA Trustee and each other Applicable Certificateholder, on the third Business Day next following the expiry of such 15-day notice period, provided that (A) if prior to the end of such 15-day period any other Applicable Certificateholder (other than the Company or any of its Affiliates) notifies such purchasing Applicable Certificateholder that such other Applicable Certificateholder wants to participate in such purchase, then such other Applicable Certificateholder (other than the Company or any of its Affiliates) may join with the purchasing Applicable Certificateholder to purchase all, but not less than all, of the Class AA Certificates pro rata based on the Fractional Undivided Interest in the Applicable Trust held by each such Applicable Certificateholder and (B) if prior to the end of such 15-day period any other Applicable Certificateholder fails to notify the purchasing Applicable Certificateholder of such other Applicable Certificateholder’s desire to participate in such a purchase, then such other Applicable Certificateholder shall lose its right to purchase the Class AA Certificates pursuant to this Section 4.01(a)(i);

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(ii)    If any Additional Certificates are issued pursuant to one or more Additional Trusts, each Additional Certificateholder (other than the Company or any of its Affiliates) shall have the right (which shall not expire upon any purchase of the Class AA Certificates pursuant to clause (i) above) to purchase all, but not less than all, of the Class AA Certificates, the Applicable Certificates, and any Additional Certificates ranked senior to the Additional Certificates held by the purchasing Additional Certificateholders upon 15 days’ written notice to the Trustee, the Class AA Trustee, any Additional Trustee with respect to Additional Certificates that rank senior to the Additional Certificates held by the purchasing Additional Certificateholders and each other Additional Certificateholder of the same class, on the third Business Day next following the expiry of such 15-day notice period, provided that (A) if prior to the end of such 15-day period any other Additional Certificateholder of such class (other than the Company or any of its Affiliates) notifies such purchasing Additional Certificateholder that such other Additional Certificateholder wants to participate in such purchase, then such other Additional Certificateholder (other than the Company or any of its Affiliates) may join with the purchasing Additional Certificateholder to purchase all, but not less than all, of the Class AA Certificates, the Applicable Certificates and such senior Additional Certificates pro rata based on the Fractional Undivided Interest in the applicable Additional Trust held by each such Additional Certificateholder and (B) if prior to the end of such 15-day period any other Additional Certificateholder of such class fails to notify the purchasing Additional Certificateholder of such other Additional Certificateholder’s desire to participate in such a purchase, then such other Additional Certificateholder shall lose its right to purchase the Class AA Certificates, the Applicable Certificates and such senior Additional Certificates pursuant to this Section 4.01(a)(ii); and

(iii)     If any Refinancing Certificates are issued, each Refinancing Certificateholder shall have the same right (subject to the same terms and conditions) to purchase Certificates pursuant to this Section 4.01(a) (and to receive notice in connection therewith) as the Certificateholders of the Class that such Refinancing Certificates refinanced.

The purchase price with respect to the Applicable Certificates shall be equal to the Pool Balance of the Applicable Certificates, together with accrued and unpaid interest thereon to the date of such purchase, without premium (including Make-Whole Amount), but including any other amounts then due and payable to the Applicable Certificateholders under the Agreement, the Intercreditor Agreement, the Escrow Agreement or any Note Document or on or in respect of the Applicable Certificates; provided, however, that no such purchase of Applicable Certificates shall be effective unless the purchaser(s) shall certify to the Trustee that contemporaneously with such purchase, such purchaser(s) is (are) purchasing, pursuant to the terms of the Agreement and the Other Agreements, all of the Applicable Certificates, the Class AA Certificates and, if applicable, the Additional Certificates that rank senior to the Additional Certificates held by the purchasing Additional Certificateholder(s). Each payment of the purchase price of the Applicable Certificates referred to in the first sentence hereof shall be made to an account or accounts designated by the Trustee and each such purchase shall be subject to the terms of this Section 4.01. Each Applicable Certificateholder agrees by its acceptance of its Applicable Certificate that (at any time after the occurrence of a Certificate Buyout Event) it will, upon payment from such Class AA Certificateholder(s), Additional Certificateholder(s) or Refinancing Certificateholder(s), as the case may be, of the purchase price set forth in the first sentence of

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this paragraph, (i) forthwith sell, assign, transfer and convey to the purchaser(s) thereof (without recourse, representation or warranty of any kind except for its own acts), all of the right, title, interest and obligation of such Applicable Certificateholder in the Agreement, the Escrow Agreement, the Deposit Agreement, the Intercreditor Agreement, the Liquidity Facility, the NPA, the Note Documents and all Applicable Certificates and Escrow Receipts held by such Applicable Certificateholder (excluding all right, title and interest under any of the foregoing to the extent such right, title or interest is with respect to an obligation not then due and payable as respects any action or inaction or state of affairs occurring prior to such sale) (and the purchaser shall assume all of such Applicable Certificateholder’s obligations under the Agreement, the Escrow Agreement, the Deposit Agreement, the Intercreditor Agreement, the Liquidity Facility, the NPA, the Note Documents and all such Applicable Certificates and Escrow Receipts), (ii) if such purchase occurs after a record date specified in Section 2.03 of the Escrow Agreement relating to the distribution of unused Deposits and/or accrued and unpaid interest on Deposits and prior to or on the related distribution date thereunder, forthwith turn over to the purchaser(s) of its Applicable Certificate all amounts, if any, received by it on account of such distribution, and (iii) if such purchase occurs after a Record Date relating to any distribution and prior to or on the related Distribution Date, forthwith turn over to the purchaser(s) of its Applicable Certificate all amounts, if any, received by it on account of such distribution. The Applicable Certificates will be deemed to be purchased on the date payment of the purchase price is made notwithstanding the failure of the Applicable Certificateholders to deliver any Applicable Certificates and, upon such a purchase, (I) the only rights of the Applicable Certificateholders will be to deliver the Applicable Certificates to the purchaser(s) and receive the purchase price for such Applicable Certificates and (II) if the purchaser(s) shall so request, such Applicable Certificateholder will comply with all the provisions of Section 3.04 of the Basic Agreement to enable new Applicable Certificates to be issued to the purchaser in such denominations as it shall request. All charges and expenses in connection with the issuance of any such new Applicable Certificates shall be borne by the purchaser thereof.

As used in this Section 4.01 and elsewhere in this Trust Supplement, the terms “Additional Certificate”, “Additional Certificateholder”, “Additional Equipment Notes”, “Additional Trust”, “Class AA Certificate”, “Class AA Certificateholder”, “Class AA Trust”, “Class AA Trust Agreement”, “Class AA Trustee”, “Refinancing Certificates”, “Refinancing Certificateholder”, “Refinancing Equipment Notes” and “Refinancing Trust” shall have the respective meanings assigned to such terms in the Intercreditor Agreement.

(b)    This Section 4.01 supersedes and replaces Section 6.01(b) of the Basic Agreement, with respect to the Applicable Trust.

Section 4.02. Amendment of Section 6.05 of the Basic Agreement. Section 6.05 of the Basic Agreement shall be amended, with respect to the Applicable Trust, by deleting the phrase “and thereby annul any Direction given by such Certificateholders or the Trustee to such Loan Trustee with respect thereto,” set forth in the first sentence thereof.

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ARTICLE V

THE TRUSTEE

Section 5.01. Acquisition of Trust Property. (a) The Trustee is hereby irrevocably authorized and directed to execute and deliver the Assignment and Assumption Agreement on the date specified in Section 7.01 of the Related Pass Through Trust Supplement, subject only to the satisfaction of the conditions set forth in said Section 7.01. The Agreement (except only for this sentence and the immediately preceding sentence hereof, which are effective upon execution and delivery hereof) shall become effective upon the execution and delivery of the Assignment and Assumption Agreement by the Trustee and the Related Trustee, automatically and without any further signature or action on the part of the Company and the Trustee, and shall thereupon constitute the legal, valid and binding obligation of the parties hereto enforceable against each of the parties hereto in accordance with its terms. Upon such execution and delivery of the Assignment and Assumption Agreement, the Related Trust shall be terminated, the Applicable Certificateholders shall receive beneficial interests in the Applicable Trust in exchange for their interests in the Related Trust equal to their respective beneficial interests in the Related Trust and the “Outstanding” (as defined in the Related Pass Through Trust Agreement) pass through certificates representing Fractional Undivided Interests in the Related Trust shall be deemed for all purposes of the Agreement, without further signature or action of any party or Certificateholder, to be Certificates representing the same Fractional Undivided Interests in the Applicable Trust and Trust Property. By acceptance of its Applicable Certificate, each Applicable Certificateholder consents to and ratifies such assignment, transfer and delivery of the trust property of the Related Trust to the Trustee upon the execution and delivery of the Assignment and Assumption Agreement. The provisions of this Section 5.01(a) supersede and replace the provisions of Section 2.02 of the Basic Agreement with respect to the Applicable Trust, and all provisions of the Basic Agreement relating to Postponed Notes or Section 2.02 of the Basic Agreement shall not apply to the Applicable Trust.

(b)     The Trustee, upon the execution and delivery of the Assignment and Assumption Agreement, acknowledges its acceptance of all right, title and interest in and to the Trust Property and declares that the Trustee holds and will hold such right, title and interest for the benefit of all then present and future Applicable Certificateholders, upon the trusts herein and in the Basic Agreement set forth. By the acceptance of each Applicable Certificate issued to it under the Related Pass Through Trust Agreement and deemed issued under the Agreement, each Holder of any such Applicable Certificate as grantor of the Applicable Trust thereby joins in the creation and declaration of the Applicable Trust. The provisions of this Section 5.01(b) supersede and replace the provisions of Section 2.03 of the Basic Agreement, with respect to the Applicable Trust.

Section 5.02. [Intentionally Omitted].

Section 5.03. The Trustee. (a) Subject to Section 5.04 of this Trust Supplement and Section 7.15 of the Basic Agreement, the Trustee shall not be responsible in any manner whatsoever for or in respect of the validity or sufficiency of this Trust Supplement, the Deposit Agreement, the NPA or the Escrow Agreement or the due execution hereof or thereof by the Company or the other parties thereto (other than the Trustee), or for or in respect of the recitals and statements contained herein or therein, all of which recitals and statements are made solely by the Company, except that the Trustee hereby represents and warrants that each of this Trust Supplement, the Basic Agreement, each Applicable Certificate, the Intercreditor Agreement, the NPA and the Escrow Agreement has been executed and delivered by one of its officers who is duly authorized to execute and deliver such document on its behalf.

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(b)    Except as herein otherwise provided and except during the continuation of an Event of Default in respect of the Applicable Trust created hereby, no duties, responsibilities or liabilities are assumed, or shall be construed to be assumed, by the Trustee by reason of this Trust Supplement other than as set forth in the Agreement, and this Trust Supplement is executed and accepted on behalf of the Trustee, subject to all the terms and conditions set forth in the Agreement, as fully to all intents as if the same were herein set forth at length.

Section 5.04. Representations and Warranties of the Trustee. The Trustee hereby represents and warrants that, on the Transfer Date:

(a)    The Trustee has full power, authority and legal right to receive the Trust Property assigned by the Related Trustee, assume the obligations under, and perform, the Assignment and Assumption Agreement, this Trust Supplement, the Intercreditor Agreement, the Escrow Agreement, the NPA and the Note Documents to which it is a party and has taken all necessary action to authorize such receipt, assumption and performance by it of this Trust Supplement, the Intercreditor Agreement, the Escrow Agreement, the NPA and the Note Documents to which it is or is to become a party;

(b)    The receipt of the Trust Property under the Assignment and Assumption Agreement and the performance by the Trustee of the Assignment and Assumption Agreement, this Trust Supplement, the Intercreditor Agreement, the Escrow Agreement, the NPA and the Note Documents to which it is or is to become a party (i) will not violate any provision of any United States federal law or the law of the state of the United States where it is located governing the banking and trust powers of the Trustee or any order, writ, judgment, or decree of any court, arbitrator or governmental authority applicable to the Trustee or any of its assets, (ii) will not violate any provision of the articles of association or by-laws of the Trustee, and (iii) will not violate any provision of, or constitute, with or without notice or lapse of time, a default under, or result in the creation or imposition of any lien on any properties included in the Trust Property pursuant to the provisions of any mortgage, indenture, contract, agreement or other undertaking to which it is a party, which violation, default or lien could reasonably be expected to have an adverse effect on the Trustee’s performance or ability to perform its duties hereunder or thereunder or on the transactions contemplated herein or therein;

(c)    The receipt of the Trust Property under the Assignment and Assumption Agreement and the performance by the Trustee of the Assignment and Assumption Agreement, this Trust Supplement, the Intercreditor Agreement, the Escrow Agreement, the NPA and the Note Documents to which it is or is to become a party will not require the authorization, consent, or approval of, the giving of notice to, the filing or registration with, or the taking of any other action in respect of, any governmental authority or agency of the United States or the state of the United States where it is located regulating the banking and corporate trust activities of the Trustee; and

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(d)    The Assignment and Assumption Agreement has been duly executed and delivered by the Trustee and this Trust Supplement, the Intercreditor Agreement, the Escrow Agreement, the NPA and the Note Documents to which it is or is to become a party have been, or will be, as applicable, duly executed and delivered by the Trustee and constitute, or will constitute, as applicable, the legal, valid and binding agreements of the Trustee, enforceable against it in accordance with their respective terms; provided, however, that enforceability may be limited by (i) applicable bankruptcy, insolvency, reorganization, moratorium or similar laws affecting the rights of creditors generally and (ii) general principles of equity.

Section 5.05. Trustee Liens. The Trustee in its individual capacity agrees, in addition to the agreements contained in Section 7.17 of the Basic Agreement, that it will at its own cost and expense promptly take any action as may be necessary to duly discharge and satisfy in full any Trustee’s Liens on or with respect to the Trust Property which is attributable to the Trustee in its individual capacity and which is unrelated to the transactions contemplated by the Intercreditor Agreement or the NPA.

ARTICLE VI

ADDITIONAL AMENDMENT; SUPPLEMENTAL AGREEMENTS

Section 6.01. Amendment of Section 5.02 of the Basic Agreement. Section 5.02 of the Basic Agreement shall be amended, with respect to the Applicable Trust, by (i) replacing the phrase “of the Note Documents and of this Agreement” set forth in paragraph (b) thereof with the phrase “of the Note Documents, of the NPA and of this Agreement” and (ii) replacing the phrase “of this Agreement and any Note Document” set forth in the last paragraph of Section 5.02 with the phrase “of this Agreement, the NPA and any Note Document”.

Section 6.02. Supplemental Agreements without Consent of Applicable Certificateholders. Without limitation of Section 9.01 of the Basic Agreement, under the terms of, and subject to the limitations contained in, Section 9.01 of the Basic Agreement, the Company may (but will not be required to), and the Trustee (subject to Section 9.03 of the Basic Agreement) shall, at the Company’s request, at any time and from time to time:

(i)     Enter into one or more agreements supplemental to the Escrow Agreement, the NPA or the Deposit Agreement for any of the purposes set forth in clauses (1) through (9) of such Section 9.01, and (without limitation of the foregoing or Section 9.01 of the Basic Agreement) (a) clauses (2) and (3) of such Section 9.01 shall also be deemed to include the Company’s obligations under (in the case of clause (2)), and the Company’s rights and powers conferred by (in the case of clause (3)), the NPA, and (b) references in clauses (4), (6) and (7) of such Section 9.01 to “any Intercreditor Agreement or any Liquidity Facility” shall also be deemed to refer to “the Intercreditor Agreement, the Liquidity Facility, the Escrow Agreement, the NPA or the Deposit Agreement”,

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(ii)    Enter into one or more agreements supplemental to the Agreement, the Intercreditor Agreement or the NPA to provide for the formation of one or more Additional Trusts, the issuance of Additional Certificates, the purchase by an Additional Trust (if any) of applicable Additional Equipment Notes and other matters incidental thereto or otherwise contemplated by Section 2.01(b) of the Basic Agreement, subject to the provisions of Section 4(a)(vi) of the NPA and Section 9.1(d) of the Intercreditor Agreement, and

(iii)     Enter into one or more agreements supplemental to the Agreement to provide for the formation of one or more Refinancing Trusts, the issuance of Refinancing Certificates, the purchase by any Refinancing Trust of applicable Refinancing Equipment Notes and other matters incidental thereto or as otherwise contemplated by Section 2.01(b) of the Basic Agreement, subject to the provisions of Section 4(a)(vi) of the NPA and Section 9.1(c) of the Intercreditor Agreement.

Section 6.03. Supplemental Agreements with Consent of Applicable Certificateholders. Without limitation of Section 9.02 of the Basic Agreement, the provisions of Section 9.02 of the Basic Agreement shall apply to agreements or amendments for the purpose of adding any provisions to or changing in any manner or eliminating any of the provisions of the Escrow Agreement, the Deposit Agreement, the Liquidity Facility or the NPA or modifying in any manner the rights and obligations of the Applicable Certificateholders under the Escrow Agreement, the Deposit Agreement, the Liquidity Facility or the NPA; provided that the provisions of Section 9.02(1) of the Basic Agreement shall be deemed to include reductions in any manner of, or delay in the timing of, any receipt by the Applicable Certificateholders of payments upon the Deposits.

Section 6.04. Consent of Holders of Certificates Issued under Other Trusts. Notwithstanding any provision in Section 6.02 or Section 6.03 of this Trust Supplement to the contrary, no amendment or modification of Section 4.01 of this Trust Supplement shall be effective unless the trustee for each Class of Certificates affected by such amendment or modification shall have consented thereto.

ARTICLE VII

TERMINATION OF TRUST

Section 7.01. Termination of the Applicable Trust. (a) The respective obligations and responsibilities of the Company and the Trustee with respect to the Applicable Trust shall terminate upon the distribution to all Applicable Certificateholders and the Trustee of all amounts required to be distributed to them pursuant to the Agreement and the disposition of all property held as part of the Trust Property; provided, however, that in no event shall the Applicable Trust continue beyond one hundred ten (110) years following the date of the execution of this Trust Supplement.

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Notice of any termination, specifying the Distribution Date upon which the Applicable Certificateholders may surrender their Applicable Certificates to the Trustee for payment of the final distribution and cancellation, shall be mailed promptly by the Trustee to Applicable Certificateholders not earlier than the 60th day and not later than the 15th day next preceding such final Distribution Date specifying (A) the Distribution Date upon which the proposed final payment of the Applicable Certificates will be made upon presentation and surrender of Applicable Certificates at the office or agency of the Trustee therein specified, (B) the amount of any such proposed final payment, and (C) that the Record Date otherwise applicable to such Distribution Date is not applicable, payments being made only upon presentation and surrender of the Applicable Certificates at the office or agency of the Trustee therein specified. The Trustee shall give such notice to the Registrar at the time such notice is given to Applicable Certificateholders. Upon presentation and surrender of the Applicable Certificates in accordance with such notice, the Trustee shall cause to be distributed to Applicable Certificateholders such final payments.

In the event that all of the Applicable Certificateholders shall not surrender their Applicable Certificates for cancellation within six months after the date specified in the above-mentioned written notice, the Trustee shall give a second written notice to the remaining Applicable Certificateholders to surrender their Applicable Certificates for cancellation and receive the final distribution with respect thereto. No additional interest shall accrue on the Applicable Certificates after the Distribution Date specified in the first written notice. In the event that any money held by the Trustee for the payment of distributions on the Applicable Certificates shall remain unclaimed for two years (or such lesser time as the Trustee shall be satisfied, after sixty days’ notice from the Company, is one month prior to the escheat period provided under applicable law) after the final distribution date with respect thereto, the Trustee shall pay to each Loan Trustee the appropriate amount of money relating to such Loan Trustee and shall give written notice thereof to the Company.

(b)    The provisions of this Section 7.01 supersede and replace the provisions of Section 11.01 of the Basic Agreement in its entirety, with respect to the Applicable Trust.

ARTICLE VIII

MISCELLANEOUS PROVISIONS

Section 8.01. Basic Agreement Ratified. Except and so far as herein expressly provided, all of the provisions, terms and conditions of the Basic Agreement are in all respects ratified and confirmed; and the Basic Agreement and this Trust Supplement shall be taken, read and construed as one and the same instrument. All replacements of provisions of, and other modifications of the Basic Agreement set forth in this Trust Supplement are solely with respect to the Applicable Trust.

Section 8.02. GOVERNING LAW. THE AGREEMENT AND THE APPLICABLE CERTIFICATES SHALL BE GOVERNED BY AND CONSTRUED IN ACCORDANCE WITH THE LAWS OF THE STATE OF NEW YORK. THIS SECTION 8.02 SUPERSEDES AND REPLACES SECTION 12.05 OF THE BASIC AGREEMENT, WITH RESPECT TO THE APPLICABLE TRUST.

Section 8.03. Execution in Counterparts. This Trust Supplement may be executed in any number of counterparts, each of which shall be an original, but such counterparts shall together constitute but one and the same instrument.

22

Section 8.04. Intention of Parties. The parties hereto intend that the Applicable Trust be classified for U.S. federal income tax purposes as a grantor trust under Subpart E, Part I of Subchapter J of the Internal Revenue Code of 1986, as amended, and not as a trust or association taxable as a corporation or as a partnership. Each Applicable Certificateholder and Investor, by its acceptance of its Applicable Certificate or a beneficial interest therein, agrees to treat the Applicable Trust as a grantor trust for all U.S. federal, state and local income tax purposes. The powers granted and obligations undertaken pursuant to the Agreement shall be so construed so as to further such intent.

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IN WITNESS WHEREOF, the Company and the Trustee have caused this Trust Supplement to be duly executed by their respective officers thereto duly authorized, as of the day and year first written above.

Signature Page to Class A-S Trust Supplement 19-1

Exhibit 4.5

EXECUTION VERSION

REVOLVING CREDIT AGREEMENT

(2019-1AA)

dated as of February 11, 2019

between

WILMINGTON TRUST, NATIONAL ASSOCIATION,

as Subordination Agent,

as Agent and Trustee for the

United Airlines Pass Through Trust 2019-1AA,

as Borrower

and

NATIONAL AUSTRALIA BANK LIMITED,

ACTING THROUGH ITS NEW YORK BRANCH

as Liquidity Provider

Relating to United Airlines

Pass Through Trust 2019-1AA 4.15% United Airlines

Pass Through Certificates, Series 2019-1AA

TABLE OF CONTENTS

i

TABLE OF CONTENTS

(continued)

ii

REVOLVING CREDIT AGREEMENT (2019-1AA)

THIS REVOLVING CREDIT AGREEMENT (2019-1AA) dated as of February 11, 2019 (the “Agreement”), between WILMINGTON TRUST, NATIONAL ASSOCIATION, a national banking association, not in its individual capacity but solely as Subordination Agent under the Intercreditor Agreement (each as defined below), as agent and trustee for the Class AA Trust (as defined below) (the “Borrower”), and NATIONAL AUSTRALIA BANK LIMITED, an Australian corporation, acting through its New York branch (the “Liquidity Provider”).

W I T N E S S E T H:

WHEREAS, pursuant to the Class AA Trust Agreement (such term and all other capitalized terms used in these recitals having the meanings set forth or referred to in Section 1.01), the Class AA Trust is issuing the Class AA Certificates; and

WHEREAS, the Borrower, in order to support the timely payment of a portion of the interest on the Class AA Certificates in accordance with their terms, has requested the Liquidity Provider to enter into this Agreement, providing in part for the Borrower to request in specified circumstances that Advances be made hereunder.

NOW, THEREFORE, in consideration of the premises, the parties hereto agree as follows:

ARTICLE I

DEFINITIONS

Section 1.01 Certain Defined Terms. (a) Definitions. As used in this Agreement and unless otherwise expressly indicated, or unless the context clearly requires otherwise, the following capitalized terms shall have the following respective meanings for all purposes of this Agreement:

“Additional Costs” has the meaning assigned to such term in Section 3.01.

“Advance” means an Interest Advance, a Final Advance, a Provider Advance, a Special Termination Advance, an Applied Special Termination Advance, or an Applied Provider Advance, as the case may be.

“Applicable Liquidity Rate” has the meaning assigned to such term in Section 3.07(h).

“Applicable Margin” means (x) with respect to any Unpaid Advance (including, without limitation, any Applied Special Termination Advance but excluding any Unapplied Special Termination Advance) or Applied Provider Advance, the margin per annum specified in item 1 of Schedule A, or (y) with respect to any Unapplied Provider Advance or any Unapplied Special Termination Advance, the margin per annum specified in the Fee Letter applicable to this Agreement.

[Revolving Credit Agreement (2019-1AA)]

“Applied Downgrade Advance” has the meaning assigned to such term in Section 2.06(a).

“Applied Non-Extension Advance” has the meaning assigned to such term in Section 2.06(a).

“Applied Provider Advance” has the meaning assigned to such term in Section 2.06(a).

“Applied Special Termination Advance” has the meaning assigned to such term in Section 2.05.

“Assignment and Assumption Agreement” means the Assignment and Assumption Agreement to be entered into between the Borrower and the trustee of the Successor Trust, substantially in the form of Exhibit C to the Trust Supplement No. 2019-1AA-O, dated as of the date hereof, relating to the Class AA Trust.

“Bail-in Action” means the application of any write-down or conversion powers by an EEA Resolution Authority in respect of any liability of an EEA Financial Institution.

“Base Rate” means, for any given day, a fluctuating interest rate per annum in effect from time to time, which rate per annum shall at all times be equal to (a) the weighted average of the rates on overnight Federal funds transactions with members of the Federal Reserve System arranged by Federal funds brokers, as published for such day (or, if such day is not a Business Day, for the next preceding Business Day) by the Federal Reserve Bank of New York, or if such rate is not so published for any day that is a Business Day, the average of the quotations for such day for such transactions received by the Liquidity Provider from three Federal funds brokers of recognized standing selected by it, plus (b) one-quarter of one percent (¹⁄₄ of 1%).

“Base Rate Advance” means an Advance that bears interest at a rate based upon the Base Rate.

“Basel III” has the meaning assigned to such term in Section 3.01.

“Borrower” has the meaning assigned to such term in the recital of parties to this Agreement.

“Borrowing” means the making of Advances requested by delivery of a Notice of Borrowing.

“Business Day” means any day other than a Saturday or Sunday or a day on which commercial banks are required or authorized to close in Chicago, Illinois, New York, New York or, so long as any Class AA Certificate is outstanding, the city and state in which the Class AA Trustee, the Borrower or any Loan Trustee maintains its Corporate Trust Office or receives or disburses funds, and, if the applicable Business Day relates to any Advance or other amount bearing interest based on the LIBOR Rate, on which dealings in dollars are carried on in the London interbank market.

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[Revolving Credit Agreement (2019-1AA)]

“Deposit Agreement” means the Deposit Agreement dated as of the date hereof between U.S. Bank National Association, as Escrow Agent, and Sumitomo Mitsui Banking Corporation, acting through its New York Branch, as Depositary, pertaining to the Class AA Certificates, as the same may be amended, modified or supplemented from time to time in accordance with the terms thereof.

“Depositary” has the meaning assigned to such term in the Deposit Agreement.

“Deposits” has the meaning assigned to such term in the Deposit Agreement.

“Downgrade Advance” means an Advance made pursuant to Section 2.02(c).

“EEA Financial Institution” means (a) any credit institution or investment firm established in any EEA Member Country which is subject to the supervision of an EEA Resolution Authority, (b) any entity established in an EEA Member Country which is a parent of an institution described in clause (a) of this definition, or (c) any financial institution established in an EEA Member Country which is a subsidiary of an institution described in clauses (a) or (b) of this definition and is subject to consolidated supervision with its parent.

“EEA Member Country” means any of the member states of the European Union, Iceland, Liechtenstein, and Norway.

“EEA Resolution Authority” means any public administrative authority or any person entrusted with public administrative authority of any EEA Member Country (including any delegee) having responsibility for the resolution of any EEA Financial Institution.

“Effective Date” has the meaning assigned to such term in Section 4.01. The delivery of the certificate of the Liquidity Provider contemplated by Section 4.01(e) shall be conclusive evidence that the Effective Date has occurred.

“Excluded Taxes” means (i) taxes imposed on the overall net income of the Liquidity Provider or of its Facility Office by the jurisdiction where such Liquidity Provider’s principal office or such Facility Office is located, and (ii) Excluded Withholding Taxes.

“Excluded Withholding Taxes” means (i) withholding Taxes imposed by the United States except to the extent that such United States withholding Taxes are imposed or increased as a result of any change in applicable law (excluding from change in applicable law for this purpose a change in an applicable treaty or other change in law affecting the applicability of a treaty) after the date hereof, or in the case of a successor Liquidity Provider (including a transferee of an Advance) or Facility Office, after the date on which such successor Liquidity Provider obtains its interest or on which the Facility Office is changed, (ii) any withholding Taxes imposed by the United States which are imposed or increased as a result of the Liquidity Provider failing to deliver to the Borrower any certificate or document (which certificate or document in the good faith judgment of the Liquidity Provider it is legally entitled to provide) which is reasonably requested by the Borrower to establish that payments under this Agreement are exempt from (or entitled to a reduced rate of) withholding Tax and (iii) Taxes imposed under Sections 1471 through 1474 of the Internal Revenue Code of 1986, as amended.

3

[Revolving Credit Agreement (2019-1AA)]

“Expenses” means liabilities, obligations, damages, settlements, penalties, claims, actions, suits, costs, expenses, and disbursements (including, without limitation, reasonable fees and disbursements of legal counsel and costs of investigation), provided that Expenses shall not include any Taxes.

“Expiry Date” means the “Initial Expiry Date” specified in item 2 of Schedule A, initially, or any subsequent anniversary date of the Closing Date to which the Expiry Date is automatically extended pursuant to Section 2.10 if the Liquidity Provider has not provided notice in accordance with Section 2.10 that its obligation to make Advances shall not be extended beyond such anniversary date.

“Facility Office” means the office of the Liquidity Provider presently located in New York, New York or such other office as the Liquidity Provider from time to time shall notify the Borrower as its Facility Office hereunder; provided that the Liquidity Provider shall not change its Facility Office to another Facility Office outside the United States of America except in accordance with Section 3.01, 3.02 or 3.03 hereof or with the prior consent of United Airlines, Inc.

“Final Advance” means an Advance made pursuant to Section 2.02(d).

“GAAP” means generally accepted accounting principles as set forth in the statements of financial accounting standards issued by the Financial Accounting Standards Board of the American Institute of Certified Public Accountants, as such principles may at any time or from time to time be varied by any applicable financial accounting rules or regulations issued by the Securities and Exchange Commission and, with respect to any person, shall mean such principles applied on a basis consistent with prior periods except as may be disclosed in such person’s financial statements.

“Head Office” has the meaning assigned to such term in Section 7.18.

“Intercreditor Agreement” means the Intercreditor Agreement dated as of the date hereof among the Trustees, the Liquidity Provider, the liquidity provider under the other Liquidity Facility and the Subordination Agent, as the same may be amended, supplemented or otherwise modified from time to time in accordance with its terms.

“Interest Advance” means an Advance made pursuant to Section 2.02(a).

“Interest Period” means, with respect to any LIBOR Advance, each of the following periods:

(i) the period beginning on the third LIBOR Business Day following either (x) the date of the Liquidity Provider’s receipt of the Notice of Borrowing for such LIBOR Advance or (y) the date of the withdrawal of funds from the Class AA Cash Collateral Account for the purpose of paying interest on the Class AA Certificates as contemplated by Section 2.06(a) hereof and, in either case, ending on the next Regular Distribution Date (or, if such day is not a Business Day, the next succeeding Business Day); and

(ii) each subsequent period commencing on the last day of the immediately preceding Interest Period and ending on the next Regular Distribution Date (or, if such day is not a Business Day, the next succeeding Business Day);

4

[Revolving Credit Agreement (2019-1AA)]

provided, however, that if (x) the Final Advance shall have been made, or (y) other outstanding Advances shall have been converted into the Final Advance, then the Interest Periods shall be successive periods of one month beginning on the third LIBOR Business Day following the Liquidity Provider’s receipt of the Notice of Borrowing for such Final Advance (in the case of clause (x) above) or the Regular Distribution Date (or, if such day is not a Business Day, the next succeeding Business Day) following such conversion (in the case of clause (y) above).

“LIBOR Advance” means an Advance bearing interest at a rate based upon the LIBOR Rate.

“LIBOR Business Day” means any day on which dealings in dollars are carried on in the London interbank market.

“LIBOR Rate” means, with respect to any Interest Period,

(i) the rate per annum appearing on display page Reuters Screen LIBOR01 Page (or any successor or substitute therefor) at approximately 11:00 a.m. (London time) two LIBOR Business Days before the first day of such Interest Period, as the rate for dollar deposits with a maturity comparable to such Interest Period, or

(ii) if the rate calculated pursuant to clause (i) above is not available, the average (rounded upwards, if necessary, to the next 1/16 of 1%) of the rates per annum at which deposits in dollars are offered for the relevant Interest Period by three banks of recognized standing selected by the Liquidity Provider in the London interbank market at approximately 11:00 a.m. (London time) two LIBOR Business Days before the first day of such Interest Period in an amount approximately equal to the principal amount of the LIBOR Advance to which such Interest Period is to apply and for a period comparable to such Interest Period;

provided that if the LIBOR Rate determined as provided above with respect to any Interest Period would be less than 0% per annum, then the LIBOR Rate for such Interest Period shall be deemed to be 0%.

“Liquidity Event of Default” means the occurrence of either (a) the Acceleration of all of the Equipment Notes (provided that, with respect to the period prior to the Delivery Period Expiry Date, such Equipment Notes have an aggregate outstanding principal balance in excess of the amount specified in item 3 on Schedule A) or (b) a United Bankruptcy Event.

“Liquidity Indemnitee” means (i) the Liquidity Provider, (ii) the directors, officers, employees and agents of the Liquidity Provider, and (iii) the successors and permitted assigns of the persons described in clauses (i) and (ii) inclusive.

“Liquidity Provider” has the meaning assigned to such term in the recital of parties to this Agreement.

5

[Revolving Credit Agreement (2019-1AA)]

“Maximum Available Commitment” means, subject to the proviso contained in the third sentence of Section 2.02(a), at any time of determination, (a) the Maximum Commitment at such time less (b) the aggregate amount of each Interest Advance outstanding at such time; provided that following a Downgrade Advance (subject to any reinstatement of the obligations of the Liquidity Provider pursuant to Section 2.06(d)), a Non-Extension Advance, a Special Termination Advance or a Final Advance, the Maximum Available Commitment shall be zero.

“Maximum Commitment” means initially the amount specified in item 4 on Schedule A, as such amount may be reduced from time to time in accordance with Section 2.04(a).

“Non-Excluded Tax” has the meaning assigned to such term in Section 3.03(a).

“Non-Extension Advance” means an Advance made pursuant to Section 2.02(b).

“Notice Date” has the meaning assigned to such term in Section 2.10.

“Notice of Borrowing” has the meaning assigned to such term in Section 2.02(e).

“Notice of Replacement Subordination Agent” has the meaning assigned to such term in Section 3.08.

“Performing Note Deficiency” means any time that less than 65% of the then aggregate outstanding principal amount of all Equipment Notes (other than any Additional Equipment Notes issued under any Indenture) are Performing Equipment Notes.

“Prospectus Supplement” means the final Prospectus Supplement dated the date specified in item 5 on Schedule A relating to the Certificates, as such Prospectus Supplement may be amended or supplemented.

“Provider Advance” means a Downgrade Advance or a Non-Extension Advance.

“Rate Determination Notice” has the meaning assigned to such term in Section 3.07(g).

“Regulatory Change” has the meaning assigned to such term in Section 3.01.

“Replenishment Amount” has the meaning assigned to such term in Section 2.06(b).

“Required Amount” means, for any day, the sum of the aggregate amount of interest, calculated at the rate per annum equal to the Stated Interest Rate for the Class AA Certificates, that would be payable on the Class AA Certificates on each of the three successive semi-annual Regular Distribution Dates immediately following such day or, if such day is a Regular Distribution Date, on such day and the succeeding two semi-annual Regular Distribution Dates, in each case calculated on the basis of the Pool Balance of the Class AA Certificates on such day and without regard to expected future distributions of principal on the Class AA Certificates.

“Special Termination Advance” means an Advance made pursuant to Section 2.02(g).

6

[Revolving Credit Agreement (2019-1AA)]

“Special Termination Notice” means the Notice of Termination substantially in the form of Annex VIII to this Agreement.

“Successor Trust” means United Airlines Pass Through Trust 2019-1AA-S.

“Termination Date” means the earliest to occur of the following: (i) the Expiry Date; (ii) the date on which the Borrower delivers to the Liquidity Provider a certificate, signed by a Responsible Officer of the Borrower, certifying that all of the Class AA Certificates have been paid in full (or provision has been made for such payment in accordance with the Intercreditor Agreement and the Class AA Trust Agreement) or are otherwise no longer entitled to the benefits of this Agreement; (iii) the date on which the Borrower delivers to the Liquidity Provider a certificate, signed by a Responsible Officer of the Borrower, certifying that a Replacement Liquidity Facility has been substituted for this Agreement in full pursuant to Section 3.5(e) of the Intercreditor Agreement; (iv) the fifth Business Day following the receipt by the Borrower of a Termination Notice or Special Termination Notice from the Liquidity Provider pursuant to Section 6.01 or 6.02 hereof, respectively; and (v) the date on which no Advance is or may (including by reason of reinstatement as herein provided) become available for a Borrowing hereunder.

“Termination Notice” means the Notice of Termination substantially in the form of Annex V to this Agreement.

“Transferee” has the meaning assigned to such term in Section 7.08(b).

“Unapplied Downgrade Advance” means any Downgrade Advance other than an Applied Downgrade Advance.

“Unapplied Non-Extension Advance” means any Non-Extension Advance other than an Applied Non-Extension Advance.

“Unapplied Provider Advance” means any Provider Advance other than an Applied Provider Advance.

“Unapplied Special Termination Advance” means any Special Termination Advance other than an Applied Special Termination Advance.

“Unpaid Advance” has the meaning assigned to such term in Section 2.05.

(b) Terms Defined in the Intercreditor Agreement. For all purposes of this Agreement, the following terms shall have the respective meanings assigned to such terms in the Intercreditor Agreement:

“Acceleration”, “Additional Certificates”, “Additional Equipment Notes”, “Aircraft”, “Bankruptcy Code”, “Certificate”, “Class”, “Class A Certificates”, “Class AA Certificates”, “Class AA Cash Collateral Account”, “Class AA Trust”, “Class AA Trust Agreement”, “Class AA Trustee”, “Closing Date”, “Controlling Party”, “Corporate Trust Office”, “Delivery Period Expiry Date”, “Downgraded Facility”, “Downgrade Event”, “Equipment Notes”, “Fee Letter”, “Final Legal

7

[Revolving Credit Agreement (2019-1AA)]

Distribution Date”, “Financing Agreement”, “Investment Earnings”, “Liquidity Facility”, “Liquidity Obligations”, “Loan Trustee”, “Non-Extended Facility”, “Note Purchase Agreement”, “Operative Agreements”, “Participation Agreement”, “Performing Equipment Note”, “Person”, “Pool Balance”, “Rating Agencies”, “Regular Distribution Date”, “Replacement Liquidity Facility”, “Responsible Officer”, “Scheduled Payment”, “Series AA Equipment Notes”, “Special Payment”, “Stated Interest Rate”, “Subordination Agent”, “Taxes”, “Threshold Rating”, “Transfer”, “Trust Agreement”, “Trustee”, “Underwriters”, “Underwriting Agreement”, “United”, and “United Bankruptcy Event”.

ARTICLE II

AMOUNT AND TERMS OF THE COMMITMENT

Section 2.01 The Advances. The Liquidity Provider hereby irrevocably agrees, on the terms and conditions hereinafter set forth, to make Advances to the Borrower from time to time on any Business Day during the period from the Effective Date until 1:00 p.m. (New York City time) on the Expiry Date (unless the obligations of the Liquidity Provider shall be earlier terminated in accordance with the terms of Section 2.04(b)) in an aggregate amount at any time outstanding not to exceed the Maximum Commitment.

Section 2.02 Making the Advances. (a) Interest Advances shall be made in one or more Borrowings by delivery to the Liquidity Provider of one or more written and completed Notices of Borrowing in substantially the form of Annex I attached hereto, signed by a Responsible Officer of the Borrower, in an amount not exceeding the Maximum Available Commitment at such time and shall be used solely for the payment when due of interest on the Class AA Certificates at the Stated Interest Rate therefor in accordance with Section 3.5(a) of the Intercreditor Agreement. Each Interest Advance made hereunder shall automatically reduce the Maximum Available Commitment and the amount available to be borrowed hereunder by subsequent Advances by the amount of such Interest Advance (subject to reinstatement as provided in the next sentence). Upon repayment to the Liquidity Provider in full or in part of the amount of any Interest Advance made pursuant to this Section 2.02(a), together with accrued interest thereon (as provided herein), the Maximum Available Commitment shall be reinstated by the amount of such repaid Interest Advance but not to exceed the Maximum Commitment; provided, however, that, subject to Section 2.06(d), the Maximum Available Commitment shall not be so reinstated at any time if (x) (i) a Liquidity Event of Default shall have occurred and be continuing and (ii) there is a Performing Note Deficiency or (y) a Final Advance, a Special Termination Advance, a Downgrade Advance or a Non-Extension Advance shall have been made or an Interest Advance shall have been converted into a Final Advance.

(b) A Non-Extension Advance shall be made in a single Borrowing if this Agreement is not extended in accordance with Section 3.5(d) of the Intercreditor Agreement (unless a Replacement Liquidity Facility to replace this Agreement shall have been delivered to the Borrower as contemplated by said Section 3.5(d) within the time period specified in such Section) by delivery to the Liquidity Provider of a written and completed Notice of Borrowing in substantially the form of Annex II attached hereto, signed by a Responsible Officer of the Borrower, in an amount equal to the Maximum Available Commitment at such time, and shall be used to fund the Class AA Cash Collateral Account in accordance with said Section 3.5(d) and Section 3.5(f) of the Intercreditor Agreement.

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[Revolving Credit Agreement (2019-1AA)]

(c) A Downgrade Advance shall be made in a single Borrowing upon the occurrence of a Downgrade Event (as provided for in Section 3.5(c) of the Intercreditor Agreement), unless (i) a Replacement Liquidity Facility to replace this Agreement shall have been previously delivered to the Borrower within thirty-five (35) days after the Downgrade Event or (ii) the relevant Rating Agency shall have provided confirmation within thirty (30) days after the Downgrade Event that such Downgrade Event will not result in a downgrading, withdrawal or suspension by such Rating Agency of the rating then in effect for the related Class of Certificates, in each case of clause (i) and (ii), in accordance with said Section 3.5(c), by delivery to the Liquidity Provider of a written and completed Notice of Borrowing in substantially the form of Annex III attached hereto, signed by a Responsible Officer of the Borrower, in an amount equal to the Maximum Available Commitment at such time, and shall be used to fund the Class AA Cash Collateral Account in accordance with said Section 3.5(c) and Section 3.5(f) of the Intercreditor Agreement. Upon the occurrence of a Downgrade Event, the Liquidity Provider shall promptly deliver notice thereof to the Borrower, the Class AA Trustee and United.

(d) A Final Advance shall be made in a single Borrowing upon the receipt by the Borrower of a Termination Notice from the Liquidity Provider pursuant to Section 6.01 hereof by delivery to the Liquidity Provider of a written and completed Notice of Borrowing in substantially the form of Annex IV attached hereto, signed by a Responsible Officer of the Borrower, in an amount equal to the Maximum Available Commitment at such time, and shall be used to fund the Class AA Cash Collateral Account (in accordance with Sections 3.5(f) and 3.5(i) of the Intercreditor Agreement).

(e) Each Borrowing shall be made on notice in writing (a “Notice of Borrowing”) in substantially the form required by Section 2.02(a), 2.02(b), 2.02(c), 2.02(d) or 2.02(g), as the case may be, given by the Borrower to the Liquidity Provider. If a Notice of Borrowing is delivered by the Borrower in respect of any Borrowing no later than 1:00 p.m. (New York City time) on a Business Day, upon satisfaction of the conditions precedent set forth in Section 4.02 with respect to a requested Borrowing, the Liquidity Provider shall make available to the Borrower, in accordance with its payment instructions, the amount of such Borrowing in U.S. dollars and immediately available funds, before 4:00 p.m. (New York City time) on such Business Day. If a Notice of Borrowing is delivered by the Borrower in respect of any Borrowing on a day that is not a Business Day or after 1:00 p.m. (New York City time) on a Business Day, upon satisfaction of the conditions precedent set forth in Section 4.02 with respect to a requested Borrowing, the Liquidity Provider shall make available to the Borrower, in accordance with its payment instructions, the amount of such Borrowing in U.S. dollars and in immediately available funds, before 12:00 Noon (New York City time) on the first Business Day next following the day of receipt of such Notice of Borrowing. Payments of proceeds of a Borrowing shall be made by wire transfer of immediately available funds to the Borrower in accordance with such wire transfer instructions as the Borrower shall furnish from time to time to the Liquidity Provider for such purpose. Each Notice of Borrowing shall be irrevocable and binding on the Borrower. Each Notice of Borrowing shall be effective upon receipt of a copy thereof by the Liquidity Provider at the address specified pursuant to Section 7.02.

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[Revolving Credit Agreement (2019-1AA)]

(f) Upon the making of any Advance requested pursuant to a Notice of Borrowing, in accordance with the Borrower’s payment instructions, the Liquidity Provider shall be fully discharged of its obligation hereunder with respect to such Notice of Borrowing, and the Liquidity Provider shall not thereafter be obligated to make any further Advances hereunder in respect of such Notice of Borrowing to the Borrower or to any other Person. If the Liquidity Provider makes an Advance requested pursuant to a Notice of Borrowing before 12:00 Noon (New York City time) on the second Business Day after the date of payment specified in Section 2.02(e), the Liquidity Provider shall have fully discharged its obligations hereunder with respect to such Advance and an event of default shall not have occurred hereunder. Following the making of any Advance pursuant to Section 2.02(b), (c), (d) or (g) hereof to fund the Class AA Cash Collateral Account, the Liquidity Provider shall have no interest in or rights to the Class AA Cash Collateral Account, the funds constituting such Advance or any other amounts from time to time on deposit in the Class AA Cash Collateral Account; provided that the foregoing shall not affect or impair the obligations of the Subordination Agent to make the distributions contemplated by Section 3.5(e) or (f) of the Intercreditor Agreement, and provided, further, that the foregoing shall not affect or impair the rights of the Liquidity Provider to provide written instructions with respect to the investment and reinvestment of amounts in the Class AA Cash Collateral Account to the extent provided in Section 2.2(b) of the Intercreditor Agreement. By paying to the Borrower proceeds of Advances requested by the Borrower in accordance with the provisions of this Agreement, the Liquidity Provider makes no representation as to, and assumes no responsibility for, the correctness or sufficiency for any purpose of the amount of the Advances so made and requested.

(g) A Special Termination Advance shall be made in a single Borrowing upon the receipt by the Borrower of a Special Termination Notice from the Liquidity Provider pursuant to Section 6.02, by delivery to the Liquidity Provider of a written and completed Notice of Borrowing in substantially the form of Annex VII, signed by a Responsible Officer of the Borrower, in an amount equal to the Maximum Available Commitment at such time, and shall be used to fund the Class AA Cash Collateral Account (in accordance with Section 3.5(f) and Section 3.5(m) of the Intercreditor Agreement).

Section 2.03 Fees. The Borrower agrees to pay to the Liquidity Provider the fees set forth in the Fee Letter applicable to this Agreement.

Section 2.04 Reductions or Termination of the Maximum Commitment.

(a) Automatic Reduction. Promptly following each date on which the Required Amount is reduced as a result of a reduction in the Pool Balance of the Class AA Certificates or otherwise, the Maximum Commitment shall automatically be reduced to an amount equal to such reduced Required Amount (as calculated by the Borrower); provided that on (or, as applicable, immediately following) the first Regular Distribution Date, the Maximum Commitment shall automatically be reduced to the then Required Amount. The Borrower shall give notice of any such automatic reduction of the Maximum Commitment to the Liquidity Provider within two Business Days thereof. The failure by the Borrower to furnish any such notice shall not affect such automatic reduction of the Maximum Commitment.

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[Revolving Credit Agreement (2019-1AA)]

(b) Termination. Upon the making of any Provider Advance or Special Termination Advance or the making of or conversion to a Final Advance hereunder or the occurrence of the Termination Date, the obligation of the Liquidity Provider to make further Advances hereunder shall automatically and irrevocably terminate, and the Borrower shall not be entitled to request any further Borrowing hereunder, except in the case of a Downgrade Advance, as provided in Section 2.06(d).

Section 2.05 Repayments of Interest Advances, the Special Termination Advance or the Final Advance. Subject to Sections 2.06, 2.07 and 2.09 hereof, the Borrower hereby agrees, without notice of an Advance or demand for repayment from the Liquidity Provider (which notice and demand are hereby waived by the Borrower), to pay, or to cause to be paid, to the Liquidity Provider on each date on which the Liquidity Provider shall make an Interest Advance, the Special Termination Advance or the Final Advance, an amount equal to (a) the amount of such Advance (any such Advance, until repaid, is referred to herein as an “Unpaid Advance”) (if multiple Interest Advances are outstanding any such repayment to be applied in the order in which such Interest Advances have been made, starting with the earliest), plus (b) interest on the amount of each such Unpaid Advance as provided in Section 3.07 hereof; provided that if (i) the Liquidity Provider shall make a Provider Advance at any time after making one or more Interest Advances which shall not have been repaid in accordance with this Section 2.05 or (ii) this Liquidity Facility shall become a Downgraded Facility or Non-Extended Facility at any time when unreimbursed Interest Advances have reduced the Maximum Available Commitment to zero, then such Interest Advances shall cease to constitute Unpaid Advances and shall be deemed to have been changed into an Applied Downgrade Advance or an Applied Non-Extension Advance, as the case may be, for all purposes of this Agreement (including, without limitation, for the purpose of determining when such Interest Advance is required to be repaid to the Liquidity Provider in accordance with Section 2.06 and for the purposes of Section 2.06(b)); provided, further, that amounts in respect of a Special Termination Advance withdrawn from the Class AA Cash Collateral Account for the purpose of paying interest on the Class AA Certificates in accordance with Section 3.5(f) of the Intercreditor Agreement (the amount of any such withdrawal being an “Applied Special Termination Advance”) shall thereafter (subject to Section 2.06(b)) be treated as an Interest Advance under this Agreement for purposes of determining the Applicable Liquidity Rate for interest payable thereon; provided, further, that if, following the making of a Special Termination Advance, the Liquidity Provider delivers a Termination Notice to the Borrower pursuant to Section 6.01, such Special Termination Advance shall thereafter be converted to and treated as a Final Advance under this Agreement for purposes of determining the Applicable Liquidity Rate for interest payable thereon and the obligation for repayment thereof and treated as an Applied Special Termination Advance for purposes of Section 2.6(c) of the Intercreditor Agreement, and, provided, further, that if, after making a Provider Advance, the Liquidity Provider delivers a Special Termination Notice to the Borrower pursuant to Section 6.02, any Unapplied Provider Advance shall be converted to and treated as a Special Termination Advance under this Agreement for purposes of determining the Applicable Liquidity Rate for interest payable thereon and the obligation for repayment thereof under the Intercreditor Agreement. The Borrower and the Liquidity Provider agree that the repayment in full of each Interest Advance, the Special Termination Advance and Final Advance on the date such Advance is made is intended to be a contemporaneous exchange for new value given to the Borrower by the Liquidity Provider.

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[Revolving Credit Agreement (2019-1AA)]

Section 2.06 Repayments of Provider Advances. (a) Amounts advanced hereunder in respect of a Provider Advance shall be deposited in the Class AA Cash Collateral Account, invested and withdrawn from the Class AA Cash Collateral Account as set forth in Sections 3.5(c), (d), (e) and (f) of the Intercreditor Agreement. Subject to Sections 2.07 and 2.09, the Borrower agrees to pay to the Liquidity Provider, on each Regular Distribution Date, commencing on the first Regular Distribution Date after the making of a Provider Advance, interest on the principal amount of any such Provider Advance as provided in Section 3.07; provided, however, that amounts in respect of a Provider Advance withdrawn from the Class AA Cash Collateral Account for the purpose of paying interest on the Class AA Certificates in accordance with Section 3.5(f) of the Intercreditor Agreement (the amount of any such withdrawal being (y) in the case of a Downgrade Advance, an “Applied Downgrade Advance” and (z) in the case of a Non-Extension Advance, an “Applied Non-Extension Advance” and, together with an Applied Downgrade Advance, an “Applied Provider Advance”) shall thereafter (subject to Section 2.06(b)) be treated as an Interest Advance under this Agreement for purposes of determining the Applicable Liquidity Rate for interest payable thereon and the dates on which such interest is payable; provided, further, however, that if, following the making of a Provider Advance, the Liquidity Provider delivers a Termination Notice to the Borrower pursuant to Section 6.01 hereof, such Provider Advance shall thereafter be converted to and treated as a Final Advance under this Agreement for purposes of determining the Applicable Liquidity Rate for interest payable thereon and the obligation for repayment thereof and treated as an Applied Downgrade Advance or Applied Non-Extension Advance, as the case may be, for the purposes of Section 2.6(c) of the Intercreditor Agreement. Subject to Sections 2.07 and 2.09 hereof, immediately upon the withdrawal of any amounts from the Class AA Cash Collateral Account on account of a reduction in the Required Amount, the Borrower shall repay to the Liquidity Provider a portion of the Provider Advances in a principal amount equal to the amount of such reduction, plus interest on the principal amount prepaid as provided in Section 3.07 hereof.

(b) At any time when an Applied Provider Advance or an Applied Special Termination Advance (or any portion thereof) is outstanding, upon the deposit in the Class AA Cash Collateral Account of any amount pursuant to clause “fourth” of Section 3.2 of the Intercreditor Agreement (any such amount being a “Replenishment Amount”) for the purpose of replenishing or increasing the balance thereof up to the amount of the Required Amount at such time, (i) the aggregate outstanding principal amount of all Applied Provider Advances or the Applied Special Termination Advance (and of Provider Advances treated as an Interest Advance for purposes of determining the Applicable Liquidity Rate for interest payable thereon) shall be automatically reduced by the amount of such Replenishment Amount (if multiple Applied Provider Advances are outstanding, such Replenishment Amount to be applied in the order in which such Applied Provider Advances have been made, starting with the earliest) and (ii) the aggregate outstanding principal amount of all Unapplied Provider Advances or of the Unapplied Special Termination Advance shall be automatically increased by the amount of such Replenishment Amount.

(c) Upon the provision of a Replacement Liquidity Facility in replacement of this Agreement in accordance with Section 3.5(e) of the Intercreditor Agreement, amounts remaining on deposit in the Class AA Cash Collateral Account after giving effect to any Applied Provider Advance or Applied Special Termination Advance on the date of such replacement shall be reimbursed to the replaced Liquidity Provider, but only to the extent such amounts are necessary to repay in full to the replaced Liquidity Provider all amounts owing to it hereunder.

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[Revolving Credit Agreement (2019-1AA)]

(d) If, at any time after making a Downgrade Advance, the Liquidity Provider satisfies the Threshold Rating and delivers a written notice to that effect to the Borrower and United, as of the second Business Day following receipt of such notice, (i) the Unapplied Downgrade Advance shall be withdrawn from the Class AA Cash Collateral Account and reimbursed to the Liquidity Provider, (ii) the Maximum Commitment shall be reinstated by an amount equal to the amount of such Unapplied Downgrade Advance so reimbursed, but not to exceed the Maximum Commitment and the obligation of the Liquidity Provider to make Advances shall be reinstated in an equal amount, and (iii) the proviso in the definition of Maximum Available Commitment shall no longer apply to such Downgrade Advance.

Section 2.07 Payments to the Liquidity Provider Under the Intercreditor Agreement. In order to provide for payment or repayment to the Liquidity Provider of any amounts hereunder, the Intercreditor Agreement provides that amounts available and referred to in Articles II and III of the Intercreditor Agreement, to the extent payable to the Liquidity Provider pursuant to the terms of the Intercreditor Agreement (including, without limitation, Section 3.5(f) of the Intercreditor Agreement), shall be paid to the Liquidity Provider in accordance with the terms thereof. Amounts so paid to, and not required to be returned by, the Liquidity Provider shall be applied by the Liquidity Provider to Liquidity Obligations then due and payable in accordance with the Intercreditor Agreement and shall discharge in full the corresponding obligations of the Borrower hereunder (or, if not provided for in the Intercreditor Agreement, then in such manner as the Liquidity Provider shall deem appropriate).

Section 2.08 Book Entries. The Liquidity Provider shall maintain in accordance with its usual practice an account or accounts evidencing the indebtedness of the Borrower resulting from Advances made from time to time and the amounts of principal and interest payable hereunder and paid from time to time in respect thereof; provided, however, that the failure by the Liquidity Provider to maintain such account or accounts shall not affect the obligations of the Borrower in respect of Advances.

Section 2.09 Payments from Available Funds Only. All payments to be made by the Borrower under this Agreement, including, without limitation, Sections 7.05 and 7.07, shall be made only from the amounts that constitute Scheduled Payments, Special Payments or payments under Section 8.1 of the Participation Agreements and payments under the Fee Letter applicable to this Agreement and Section 6 of the Note Purchase Agreement and only to the extent that the Borrower shall have sufficient income or proceeds therefrom to enable the Borrower to make payments in accordance with the terms hereof after giving effect to the priority of payments provisions set forth in the Intercreditor Agreement. The Liquidity Provider agrees that it will look solely to such amounts in respect of payments to be made by the Borrower hereunder to the extent available for distribution to it as provided in the Intercreditor Agreement and this Agreement and that the Borrower, in its individual capacity, is not personally liable to it for any amounts payable or liability under this Agreement except as expressly provided in this Agreement, the Intercreditor Agreement or any Participation Agreement. Amounts on deposit in the Class AA Cash Collateral Account shall be available to the Borrower to make payments under this Agreement only to the extent and for the purposes expressly contemplated in Section 3.5(f) of the Intercreditor Agreement.

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[Revolving Credit Agreement (2019-1AA)]

Section 2.10 Non-Extension of the Expiry Date; Non-Extension Advance. If in any calendar year the Liquidity Provider advises the Borrower before the 25^th day prior to the anniversary date of the Closing Date in such calendar year (such 25^th day, the “Notice Date”) that the Expiry Date shall not be extended beyond such anniversary date (and if this Agreement shall not have been replaced in accordance with Section 3.5(e) of the Intercreditor Agreement), the Borrower shall be entitled on and after such Notice Date (but prior to the then effective Expiry Date) to request a Non-Extension Advance in accordance with Section 2.02(b) hereof and Section 3.5(d) of the Intercreditor Agreement; provided, however, that if in any calendar year the Liquidity Provider does not so advise the Borrower before the Notice Date in such calendar year, the Expiry Date shall be automatically extended to the anniversary date of the Closing Date in the next calendar year.

ARTICLE III

OBLIGATIONS OF THE BORROWER

Section 3.01 Increased Costs. The Borrower shall pay to the Liquidity Provider from time to time such amounts as may be necessary to compensate the Liquidity Provider for any increased costs incurred by the Liquidity Provider which are attributable to its making or maintaining any Advances hereunder or its obligation to make any such Advances hereunder, or any reduction in any amount receivable by the Liquidity Provider under this Agreement or the Intercreditor Agreement in respect of any such Advances or such obligation (such increases in costs and reductions in amounts receivable being herein called “Additional Costs”), resulting from any change after the date of this Agreement in U.S. federal, state, municipal, or foreign laws or regulations (including Regulation D of the Board of Governors of the Federal Reserve System), or the adoption or making after the date of this Agreement of any interpretations, directives, or requirements applying to a class of banks including the Liquidity Provider under any U.S. federal, state, municipal, or any foreign laws or regulations (whether or not having the force of law) by any court, central bank or monetary authority charged with the interpretation or administration thereof (a “Regulatory Change”), which: (1) changes the basis of taxation of any amounts payable to the Liquidity Provider under this Agreement in respect of any such Advances or such obligation (other than Excluded Taxes); or (2) imposes or modifies any reserve, special deposit, compulsory loan or similar requirements relating to any extensions of credit or other assets of, or any deposits with other liabilities of, the Liquidity Provider (including any such Advances or such obligation or any deposits referred to in the definition of LIBOR Rate or related definitions). For the avoidance of doubt, any Regulatory Changes based on the consultative papers of The Basel Committee on Banking Supervision of December 2009 entitled “Strengthening the resilience of the banking sector” and “International framework for liquidity risk measurement, standards and monitoring”, in each case together with any amendments thereto (collectively, “Basel III”), will not be treated, for purposes of determining whether the Liquidity Provider is entitled to compensation under this Section 3.01, as having been adopted or having come into effect before the date hereof, and any such Regulatory Changes based on Basel III shall be determined to be adopted only when the national banking supervisory authorities, or other relevant administrative or legislative bodies having primary

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jurisdiction or regulatory authority over the Liquidity Provider, adopt any such Regulatory Changes based on Basel III in the primary jurisdiction of the Liquidity Provider. The Liquidity Provider agrees to use reasonable efforts (consistent with applicable legal and regulatory restrictions) to change the jurisdiction of its Facility Office if making such change would avoid the need for, or reduce the amount of, any amount payable under this Section that may thereafter accrue and would not, in the reasonable judgment of the Liquidity Provider, be otherwise disadvantageous to the Liquidity Provider.

The Liquidity Provider will notify the Borrower of any event occurring after the date of this Agreement that will entitle the Liquidity Provider to compensation pursuant to this Section 3.01 as promptly as practicable after it obtains knowledge thereof and determines to request such compensation, which notice shall describe in reasonable detail the calculation of the amounts owed under this Section. Determinations by the Liquidity Provider for purposes of this Section 3.01 of the effect of any Regulatory Change on its costs of making or maintaining Advances or on amounts receivable by it in respect of Advances, and of the additional amounts required to compensate the Liquidity Provider in respect of any Additional Costs, shall be prima facie evidence of the amount owed under this Section.

Notwithstanding the preceding two paragraphs, the Liquidity Provider and the Subordination Agent agree that any permitted assignee or participant of the initial Liquidity Provider which is not a bank shall not be entitled to the benefits of the preceding two paragraphs (but without limiting the provisions of Section 7.08 hereof).

Section 3.02 Capital Adequacy and Liquidity Coverage. If (1) the adoption, after the date hereof, of any applicable governmental law, rule or regulation regarding capital adequacy or liquidity coverage, (2) any change, after the date hereof, in the interpretation or administration of any such law, rule or regulation by any central bank or other governmental authority charged with the interpretation or administration thereof or (3) compliance by the Liquidity Provider or any corporation or bank controlling the Liquidity Provider with any applicable guideline or request of general applicability, issued after the date hereof, by any central bank or other governmental authority (whether or not having the force of law) that constitutes a change of the nature described in clause (2), has the effect of (x) requiring an increase in the amount of capital or liquid assets required to be maintained by the Liquidity Provider or any corporation or bank controlling the Liquidity Provider, or (y) reducing the rate of return on assets or capital of the Liquidity Provider (or such corporation or bank) and such adoption, change or compliance, as the case may be, relates to a category of claims or assets that includes the Liquidity Provider’s obligations hereunder (including funded obligations) and other similar obligations, the Borrower shall, subject to the provisions of the next paragraph, pay to the Liquidity Provider from time to time such additional amount or amounts as are necessary to compensate the Liquidity Provider for such portion of such increase or reduction as shall be reasonably allocable to the Liquidity Provider’s obligations to the Borrower hereunder. For the avoidance of doubt, the adoption of any law, rule or regulation described in clause (1) of the first sentence of this Section 3.02, and the taking of any action described in clauses (2) and (3) of such sentence, that in each case is based on Basel III, will not be treated, for purposes of determining whether the Liquidity Provider (or any corporation or bank controlling the Liquidity Provider) is entitled to compensation under this Section 3.02, as having been adopted, come into effect, been issued or been taken before the date hereof, and any such law, rule or regulation and any of the actions

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described in clauses (2) and (3) of such sentence that is based on Basel III shall be determined to have been adopted, come into effect, been issued or been taken only when the central bank or other legislative or administrative governmental authorities in the primary jurisdiction of the Liquidity Provider (or any corporation or bank controlling the Liquidity Provider) adopt any such law, rule or regulation or take any such actions. The Liquidity Provider agrees to use reasonable efforts (consistent with applicable legal and regulatory restrictions) to change the jurisdiction of its Facility Office if making such change would avoid the need for, or reduce the amount of, any amount payable under this Section that may thereafter accrue and would not, in the reasonable judgment of the Liquidity Provider, be otherwise materially disadvantageous to the Liquidity Provider.

The Liquidity Provider will notify the Borrower of any event occurring after the date of this Agreement that will entitle the Liquidity Provider to compensation pursuant to this Section 3.02 as promptly as practicable after it obtains knowledge thereof and determines to request such compensation, which notice shall describe in reasonable detail the calculation of the amounts owed under this Section. Determinations by the Liquidity Provider for purposes of this Section 3.02 of the effect of any increase in the amount of capital or liquid assets required to be maintained by the Liquidity Provider and of the amount allocable to the Liquidity Provider’s obligations to the Borrower hereunder shall be conclusive evidence of the amounts owed under this Section, absent manifest error.

Notwithstanding the preceding two paragraphs, the Liquidity Provider and the Subordination Agent agree that any permitted assignee or participant of the initial Liquidity Provider which is not a bank shall not be entitled to the benefits of the preceding two paragraphs (but without limiting the provisions of Section 7.08 hereof).

Section 3.03 Payments Free of Deductions. (a) Unless required by applicable law, all payments made by the Borrower under this Agreement shall be made free and clear of, and without reduction for or on account of, any present or future stamp or other taxes, levies, imposts, duties, charges, fees, deductions, withholdings, restrictions or conditions of any nature whatsoever now or hereafter imposed on, levied, collected, withheld or assessed, excluding Excluded Taxes (such non-excluded taxes being referred to herein, collectively, as “Non-Excluded Taxes” and each, individually, as a “Non-Excluded Tax”). If any Non-Excluded Taxes are required to be withheld from any amounts payable to the Liquidity Provider under this Agreement, (i) the Borrower shall within the time prescribed therefor by applicable law pay to the appropriate governmental or taxing authority the full amount of any such Non-Excluded Taxes (and any additional Non-Excluded Taxes in respect of the additional amounts payable under clause (ii) hereof) and make such reports or returns in connection therewith at the time or times and in the manner prescribed by applicable law, and (ii) the amounts so payable to the Liquidity Provider shall be increased to the extent necessary to yield to the Liquidity Provider (after payment of all Non-Excluded Taxes) interest or any other such amounts payable under this Agreement at the rates or in the amounts specified in this Agreement. The Liquidity Provider agrees to use reasonable efforts (consistent with its internal policy and legal and regulatory restrictions) to change the jurisdiction of its Facility Office if making such change would avoid the need for, or reduce the amount of, any such additional amounts that may thereafter accrue and would not, in the reasonable judgment of the Liquidity Provider, be otherwise disadvantageous to the Liquidity Provider. From time to time upon the reasonable request of the

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Borrower, the Liquidity Provider agrees to provide to the Borrower two original Internal Revenue Service Forms W-8BEN-E, W-8ECI or W-9, as appropriate, or any successor or other form prescribed by the Internal Revenue Service, certifying that the Liquidity Provider is exempt from or entitled to a reduced rate of United States withholding tax on payments pursuant to this Agreement. Within 30 days after the date of each payment hereunder, the Borrower shall furnish to the Liquidity Provider the original or a certified copy of (or other documentary evidence of) the payment of the Non-Excluded Taxes applicable to such payment.

(b) Unless required by applicable law, all payments (including, without limitation, Advances) made by the Liquidity Provider under this Agreement shall be made free and clear of, and without reduction for or on account of, any Taxes. If any Taxes are required to be withheld or deducted from any amounts payable to the Borrower under this Agreement, the Liquidity Provider shall (i) within the time prescribed therefor by applicable law pay to the appropriate governmental or taxing authority the full amount of any such Taxes (and any additional Taxes in respect of the additional amounts payable under clause (ii) hereof) and make such reports or returns in connection therewith at the time or times and in the manner prescribed by applicable law, and (ii) pay to the Borrower an additional amount which (after deduction of all such Taxes) will be sufficient to yield to the Borrower the full amount which would have been received by it had no such withholding or deduction been made. Within 30 days after the date of each payment hereunder, the Liquidity Provider shall furnish to the Borrower the original or a certified copy of (or other documentary evidence of) the payment of the Taxes applicable to such payment.

(c) On or before the Closing Date, the Borrower shall provide the Liquidity Provider with a fully executed Internal Revenue Service Form W-9, showing a complete exemption from U.S federal backup withholding tax. If any other exemption from, or reduction in the rate of, any Taxes required to be borne by the Liquidity Provider under Section 3.03(b) is reasonably available to the Borrower without providing any information regarding the holders or beneficial owners of the Certificates, the Borrower shall deliver the Liquidity Provider such form or forms and such other evidence of the eligibility of the Borrower for such exemption or reductions (but without any requirement to provide any information regarding the holders or beneficial owners of the Certificates) as the Liquidity Provider may reasonably identify to the Borrower as being required as a condition to exemption from, or reduction in the rate of, such Taxes.

(d) If a payment made to the Liquidity Provider or Borrower hereunder would be subject to U.S. federal withholding Tax imposed by FATCA if the Borrower or Liquidity Provider, as applicable, were to fail to comply with the applicable reporting requirements of FATCA (including those contained in Section 1471 (b) or 1472 (b) of the U.S. Internal Revenue Code, as applicable), it shall deliver to the Borrower or the Liquidity Provider, as applicable, at the time or times prescribed by law and at such time or times reasonably requested by the Borrower or Liquidity Provider, as applicable, such documentation prescribed by applicable law (including as prescribed by Section 1471 (b)(3)(C)(i) of the U.S. Internal Revenue Code) and such additional documentation reasonably requested by the Borrower or Liquidity Provider, as applicable, as may be necessary for the Borrower or Liquidity Provider, as applicable, to comply with its obligations under FATCA and to determine that the Liquidity Provider or Borrower has complied with the Liquidity Provider’s or Borrower’s obligations under FATCA or to determine the amount to deduct and withhold from such payment. Solely for purposes of this paragraph, “FATCA” shall include any amendments made to FATCA after the date of this Agreement.

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Section 3.04 Payments. The Borrower shall make or cause to be made each payment to the Liquidity Provider under this Agreement so as to cause the same to be received by the Liquidity Provider not later than 1:00 P.M. (New York City time) on the day when due. The Borrower shall make all such payments in lawful money of the United States of America, to the Liquidity Provider in immediately available funds, by wire transfer to the account specified for the Liquidity Provider in Schedule B or to such other U.S. bank account as the Liquidity Provider may from time to time direct the Borrower in writing.

Section 3.05 Computations. All computations of interest based on the Base Rate shall be made on the basis of a year of 365 or 366 days, as the case may be, and all computations of interest based on the LIBOR Rate shall be made on the basis of a year of 360 days, in each case for the actual number of days (including the first day but excluding the last day) occurring in the period for which such interest is payable.

Section 3.06 Payment on Non-Business Days. Whenever any payment to be made hereunder to the Liquidity Provider shall be stated to be due on a day other than a Business Day, such payment shall be made on the next succeeding Business Day and no additional interest shall be due as a result. If any payment in respect of interest on an Advance is so deferred to the next succeeding Business Day, such deferral shall not delay the commencement of the next Interest Period for such Advance (if such Advance is a LIBOR Advance) or reduce the number of days for which interest will be payable on such Advance on the next interest payment date for such Advance.

Section 3.07 Interest. (a) Subject to Section 2.09, the Borrower shall pay, or shall cause to be paid, without duplication, interest on (i) the unpaid principal amount of each Advance from and including the date of such Advance (or, in the case of an Applied Provider Advance or Applied Special Termination Advance, from and including the date on which the amount thereof was withdrawn from the Class AA Cash Collateral Account to pay interest on the Class AA Certificates) to but excluding the date such principal amount shall be paid in full (or, in the case of an Applied Provider Advance or Applied Special Termination Advance, the date on which the Class AA Cash Collateral Account is fully replenished in respect of such Advance) and (ii) any other amount due hereunder (whether fees, commissions, expenses or other amounts or, to the extent permitted by law, installments of interest on Advances or any such other amount) which is not paid when due (whether at stated maturity, by acceleration or otherwise) from and including the due date thereof to but excluding the date such amount is paid in full, in each such case, at a fluctuating interest rate per annum for each day equal to the Applicable Liquidity Rate (as defined below) for such Advance or such other amount, as the case may be, as in effect for such day, but in no event at a rate per annum greater than the maximum rate permitted by applicable law; provided, however, that, if at any time the otherwise applicable interest rate as set forth in this Section 3.07 shall exceed the maximum rate permitted by applicable law, then any subsequent reduction in such interest rate will not reduce the rate of interest payable pursuant to this Section 3.07 below the maximum rate permitted by applicable law until the total amount of interest accrued equals the amount of interest that would have accrued if such otherwise applicable interest rate as set forth in this Section 3.07 had at all times been in effect.

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(b) Except as provided in clause (e) below, each Advance will be either a Base Rate Advance or a LIBOR Advance as provided in this Section. Each such Advance will be a Base Rate Advance for the period from the date of its Borrowing to (but excluding) the third LIBOR Business Day following the Liquidity Provider’s receipt of the Notice of Borrowing for such Advance. Thereafter, such Advance shall be a LIBOR Advance.

(c) Each LIBOR Advance shall bear interest during each Interest Period at a rate per annum equal to the LIBOR Rate for such Interest Period plus the Applicable Margin for such LIBOR Advance, payable in arrears on the last day of such Interest Period and, in the event of the payment of principal of such LIBOR Advance on a day other than such last day, on the date of such payment (to the extent of interest accrued on the amount of principal repaid).

(d) Each Base Rate Advance shall bear interest at a rate per annum equal to the Base Rate plus the Applicable Margin for such Base Rate Advance, payable in arrears on each Regular Distribution Date and, in the event of the payment of principal of such Base Rate Advance on a day other than a Regular Distribution Date, on the date of such payment (to the extent of interest accrued on the amount of principal repaid).

(e) Each outstanding Unapplied Non-Extension Advance, Unapplied Downgrade Advance and Unapplied Special Termination Advance shall bear interest in an amount equal to the Investment Earnings on amounts on deposit in the Class AA Cash Collateral Account plus the Applicable Margin for such Unapplied Non-Extension Advance, Unapplied Downgrade Advance or Unapplied Special Termination Advance, as applicable, on the amount of such Unapplied Non-Extension Advance, Unapplied Downgrade Advance or Unapplied Special Termination Advance, as applicable, from time to time, payable in arrears on each Regular Distribution Date.

(f) Each amount not paid when due hereunder (whether fees, commissions, expenses or other amounts or, to the extent permitted by applicable law, installments of interest on Advances but excluding Advances) shall bear interest at a rate per annum equal to the Base Rate plus 2.00% per annum until paid.

(g) If at any time, the Liquidity Provider shall have determined (which determination shall be conclusive and binding upon the Borrower, absent manifest error) that, by reason of circumstances affecting the relevant interbank lending market generally, the LIBOR Rate determined or to be determined for the current or the immediately succeeding Interest Period will not adequately and fairly reflect the cost to the Liquidity Provider (as conclusively certified by the Liquidity Provider, absent manifest error) of making or maintaining LIBOR Advances, the Liquidity Provider shall give facsimile or telephonic notice thereof (a “Rate Determination Notice”) to the Borrower (any such telephonic notice to be promptly confirmed in writing and transmitted by telecopier to the Borrower in accordance with Section 7.02). If such notice is given, then the outstanding principal amount of the LIBOR Advances shall be converted to Base Rate Advances effective from the date of the Rate Determination Notice; provided that the Applicable Liquidity Rate in respect of such Base Rate Advances shall be increased by one percent (1.00%). The Liquidity Provider shall withdraw a Rate Determination Notice given hereunder when the Liquidity Provider determines that the circumstances giving rise to such Rate Determination Notice no longer apply to the Liquidity Provider, and the Base Rate Advances shall be converted to LIBOR Advances effective as of the first day of the next succeeding Interest Period after the date of such withdrawal.

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(h) Each change in the Base Rate shall become effective immediately. The rates of interest specified in this Section 3.07 with respect to any Advance or other amount shall be referred to as the “Applicable Liquidity Rate”.

Section 3.08 Replacement of Borrower. From time to time and subject to the successor Borrower’s meeting the eligibility requirements set forth in Section 6.9 of the Intercreditor Agreement applicable to the Subordination Agent, upon the effective date and time specified in a written and completed Notice of Replacement Subordination Agent in substantially the form of Annex VI attached hereto (a “Notice of Replacement Subordination Agent”) delivered to the Liquidity Provider by the then Borrower, the successor Borrower designated therein shall be substituted for the Borrower for all purposes hereunder.

Section 3.09 Funding Loss Indemnification. The Borrower shall pay to the Liquidity Provider, upon the request of the Liquidity Provider, such amount or amounts as shall be sufficient (in the reasonable opinion of the Liquidity Provider) to compensate it for any loss, cost, or expense incurred by reason of the liquidation or redeployment of deposits or other funds acquired by the Liquidity Provider to fund or maintain any LIBOR Advance (but excluding loss of anticipated profits) incurred as a result of:

(1) Any repayment of a LIBOR Advance on a date other than the last day of the Interest Period for such Advance; or

(2) Any failure by the Borrower to borrow a LIBOR Advance on the date for borrowing specified in the relevant notice under Section 2.02.

Calculation of all amounts payable to the Liquidity Provider under this Section 3.09 shall be made as though the Liquidity Provider had actually funded the related LIBOR Advance through the purchase of a LIBOR deposit bearing interest at the LIBOR Rate in an amount equal to its LIBOR Advance and having a maturity comparable to the relevant Interest Period; provided, however, that the Liquidity Provider may fund any LIBOR Advance in any manner it sees fit and the foregoing assumptions shall be utilized only for the purposes of calculating amounts payable under this Section 3.09.

Section 3.10 Illegality. Notwithstanding any other provision in this Agreement, if any change in any applicable law, rule or regulation, or any change in the interpretation or administration thereof by any governmental authority, central bank or comparable agency charged with the interpretation or administration thereof, or compliance by the Liquidity Provider (or its Facility Office) with any request or directive (whether or not having the force of law) of any such authority, central bank or comparable agency shall make it unlawful or impossible for the Liquidity Provider (or its Facility Office) to maintain or fund its LIBOR Advances, then upon notice to the Borrower by the Liquidity Provider, the outstanding principal amount of the LIBOR Advances shall be converted to Base Rate Advances (a) immediately upon demand of the Liquidity Provider, if such change or compliance with such request, in the judgment of the Liquidity Provider, requires immediate repayment; or (b) at the expiration of the

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last Interest Period to expire before the effective date of any such change or request. The Liquidity Provider agrees to use reasonable efforts (consistent with applicable legal and regulatory restrictions) to change the jurisdiction of its Facility Office if making such change would avoid or cure the aforesaid illegality and would not, in the reasonable judgment of the Liquidity Provider, be otherwise disadvantageous to the Liquidity Provider.

ARTICLE IV

CONDITIONS PRECEDENT

Section 4.01 Conditions Precedent to Effectiveness of Section 2.01. Section 2.01 of this Agreement shall become effective on and as of the first date (the “Effective Date”) on which the following conditions precedent have been satisfied or waived:

(a) The Liquidity Provider shall have received each of the following, and in the case of each document delivered pursuant to paragraphs (i), (ii) and (iii), each in form and substance satisfactory to the Liquidity Provider:

(i) This Agreement duly executed on behalf of the Borrower and the Fee Letter applicable to this Agreement duly executed on behalf of the Borrower and United;

(ii) The Intercreditor Agreement duly executed on behalf of each of the parties thereto (other than the Liquidity Provider);

(iii) Fully executed copies of each of the Operative Agreements executed and delivered on or before the Closing Date (other than this Agreement, the Fee Letter and the Intercreditor Agreement);

(iv) A copy of the Prospectus Supplement and specimen copies of the Class AA Certificates;

(v) An executed copy of each document, instrument, certificate and opinion delivered on or before the Closing Date pursuant to the Class AA Trust Agreement, the Note Purchase Agreement, the Intercreditor Agreement and the other Operative Agreements (in the case of each such opinion delivered in connection with the issuance and sale of the Class AA Certificates, other than the opinion of counsel for the Underwriters, either addressed to the Liquidity Provider or accompanied by a letter from the counsel rendering such opinion to the effect that the Liquidity Provider is entitled to rely on such opinion as of its date as if it were addressed to the Liquidity Provider);

(vi) Evidence that there shall have been made and shall be in full force and effect, all filings, recordings and/or registrations, and there shall have been given or taken any notice or other similar action as may be reasonably necessary or, to the extent reasonably requested by the Liquidity Provider, reasonably advisable, in order to establish, perfect, protect and preserve the right, title and interest, remedies, powers, privileges, liens and security interests of, or for the benefit of, the Trustees, the Borrower and the Liquidity Provider created by the Operative Agreements executed and delivered on or before the Closing Date;

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(vii) An agreement from United, pursuant to which (i) United agrees to provide to the Liquidity Provider (A) within 90 days after the end of each of the first three fiscal quarters in each fiscal year of United, a consolidated balance sheet of United as of the end of such quarter and related statements of income and cash flows for the period commencing at the end of the previous fiscal year and ending with the end of such quarter, setting forth in each case in comparative form the corresponding figures for the corresponding period in the preceding fiscal year, prepared in accordance with GAAP; provided, that so long as United is subject to the reporting requirements of the Securities Exchange Act of 1934, as amended, a copy of United’s report on Form 10-Q for such fiscal quarter (excluding exhibits) or a written notice of United that such report has been filed with the Securities and Exchange Commission, providing a website address at which such report may be accessed and confirming that the report accessible at such website address conforms to the original report filed with the Securities and Exchange Commission will satisfy this subclause (A), and (B) within 120 days after the end of each fiscal year of United, a consolidated balance sheet of United as of the end of such fiscal year and related statements of income and cash flows of United for such fiscal year, in comparative form with the preceding fiscal year, prepared in accordance with GAAP, together with a report of United’s independent certified public accountants with respect to their audit of such financial statements; provided, that so long as United is subject to the reporting requirements of the Securities Exchange Act of 1934, as amended, a copy of United’s report on Form 10-K for such fiscal year (excluding exhibits) or a written notice of United that such report has been filed with the Securities and Exchange Commission, providing a website address at which such report may be accessed and confirming that the report accessible at such website address conforms to the original report filed with the Securities and Exchange Commission will satisfy this subclause (B), and (ii) United agrees to allow the Liquidity Provider to inspect United’s books and records regarding such transactions, and to discuss such transactions with officers and employees of United;

(viii) Legal opinions from (a) Morris James LLP, special counsel to the Borrower, and (b) Hughes Hubbard & Reed LLP, special counsel to United, each in form and substance reasonably satisfactory to the Liquidity Provider; and

(ix) Such other documents, instruments, opinions and approvals pertaining to the transactions contemplated hereby or by the other Operative Agreements as the Liquidity Provider shall have reasonably requested, including, without limitation, such documentation as the Liquidity Provider may require to satisfy its “know your customer” policies.

(b) The following statement shall be true on and as of the Effective Date: no event has occurred and is continuing, or would result from the entering into of this Agreement or the making of any Advance, which constitutes a Liquidity Event of Default.

(c) The Liquidity Provider shall have received payment in full of all fees and other sums required to be paid to or for the account of the Liquidity Provider on or prior to the Effective Date.

(d) All conditions precedent to the issuance of the Certificates under the applicable Trust Agreements shall have been satisfied or waived, all conditions precedent to the effectiveness of the Liquidity Facility in respect of the Class A Certificates shall have been concurrently satisfied or waived, and all conditions precedent to the purchase of the Class AA Certificates and the Class A Certificates by the Underwriters under the Underwriting Agreement shall have been satisfied or waived.

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(e) The Borrower shall have received a certificate, dated the date hereof, signed by a duly authorized representative of the Liquidity Provider, certifying that all conditions precedent to the effectiveness of Section 2.01 have been satisfied or waived.

Section 4.02 Conditions Precedent to Borrowing. The obligation of the Liquidity Provider to make an Advance on the occasion of each Borrowing shall be subject to the conditions precedent that the Effective Date shall have occurred and, on or prior to the date of such Borrowing, the Borrower shall have delivered a Notice of Borrowing which conforms to the terms and conditions of this Agreement and has been completed as may be required by the relevant form of the Notice of Borrowing for the type of Advance requested.

Section 4.03 Representations and Warranties. The representations and warranties of the Borrower as Subordination Agent in Section 5.2 of the Participation Agreements shall be deemed to be incorporated into this Agreement as if set out in full herein and as if such representations and warranties were made by the Borrower to the Liquidity Provider.

ARTICLE V

COVENANTS

Section 5.01 Affirmative Covenants of the Borrower. So long as any Advance shall remain unpaid or the Liquidity Provider shall have any Maximum Commitment hereunder or the Borrower shall have any obligation to pay any amount to the Liquidity Provider hereunder, the Borrower will, unless the Liquidity Provider shall otherwise consent in writing:

(a) Performance of this and Other Agreements. Punctually pay or cause to be paid all amounts payable by it under this Agreement and the other Operative Agreements and observe and perform in all material respects the conditions, covenants and requirements applicable to it contained in this Agreement and the other Operative Agreements.

(b) Reporting Requirements. Furnish to the Liquidity Provider with reasonable promptness, such information and data with respect to the transactions contemplated by the Operative Agreements as from time to time may be reasonably requested by the Liquidity Provider; and permit the Liquidity Provider, upon reasonable notice, to inspect the Borrower’s books and records with respect to such transactions and to meet with officers and employees of the Borrower to discuss such transactions.

(c) Certain Operative Agreements. Furnish to the Liquidity Provider with reasonable promptness, such Operative Agreements entered into after the date hereof as from time to time may be reasonably requested by the Liquidity Provider.

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Section 5.02 Negative Covenants of the Borrower. So long as any Advance shall remain unpaid or the Liquidity Provider shall have any Maximum Commitment hereunder or the Borrower shall have any obligation to pay any amount to the Liquidity Provider hereunder, the Borrower will not appoint or permit or suffer to be appointed any successor Borrower without the prior written consent of the Liquidity Provider, which consent shall not be unreasonably withheld or delayed.

ARTICLE VI

LIQUIDITY EVENTS OF DEFAULT AND SPECIAL TERMINATION

Section 6.01 Liquidity Events of Default. If (a) any Liquidity Event of Default has occurred and is continuing and (b) there is a Performing Note Deficiency, the Liquidity Provider may, in its discretion, deliver to the Borrower a Termination Notice, the effect of which shall be to cause (i) the obligation of the Liquidity Provider to make Advances hereunder to expire on the fifth Business Day after the date on which such Termination Notice is received by the Borrower, (ii) the Borrower to promptly request, and the Liquidity Provider to promptly make, a Final Advance in accordance with Section 2.02(d) hereof and Section 3.5(i) of the Intercreditor Agreement, (iii) all other outstanding Advances to be automatically converted into Final Advances for purposes of determining the Applicable Liquidity Rate for interest payable thereon, and (iv) subject to Sections 2.07 and 2.09 hereof, all Advances (including, without limitation, any Provider Advance and Applied Provider Advance), any accrued interest thereon and any other amounts outstanding hereunder to become immediately due and payable to the Liquidity Provider.

Section 6.02 Special Termination. If the aggregate Pool Balance of the Class AA Certificates is greater than the aggregate outstanding principal amount of the Series AA Equipment Notes (other than any Series AA Equipment Notes previously sold or with respect to which the collateral securing such Series AA Equipment Notes has been disposed of) at any time during the 18 month period prior to August 25, 2031, the Liquidity Provider may, in its discretion, deliver to the Borrower a Special Termination Notice, the effect of which shall be to cause (i) the obligation of the Liquidity Provider to make Advances hereunder to expire on the fifth Business Day after the date on which such Special Termination Notice is received by the Borrower, (ii) the Borrower to promptly request, and the Liquidity Provider to promptly make, a Special Termination Advance in accordance with Section 2.02(g) and Section 3.5(m) of the Intercreditor Agreement, and (iii) subject to Sections 2.07 and 2.09, all Advances (including, without limitation, any Provider Advance and Applied Provider Advance), any accrued interest thereon and any other amounts outstanding hereunder to become immediately due and payable to the Liquidity Provider.

ARTICLE VII

MISCELLANEOUS

Section 7.01 Amendments, Etc. No amendment or waiver of any provision of this Agreement, nor consent to any departure by the Borrower therefrom, shall in any event be effective unless the same shall be in writing and signed by the Liquidity Provider, and, in the case of an amendment or of a waiver by the Borrower, the Borrower, and then such waiver or consent shall be effective only in the specific instance and for the specific purpose for which given.

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Section 7.02 Notices, Etc. Except as otherwise expressly provided herein, all notices and other communications provided for hereunder shall be in writing (including telecopier and mailed or delivered or sent by telecopier) addressed to the applicable party at its address specified on Schedule B or to such other address as shall be designated by such Person in a written notice to the others. The Borrower shall give all Notices of Borrowing via telecopier; provided, that, in the event of a transmission failure, the Borrower shall use reasonable efforts to deliver the applicable Notice of Borrowing to the Liquidity Provider on the same Business Day using such other means as may be reasonably deemed necessary by the Borrower. All such notices and communications shall be effective (i) if given by telecopier, when transmitted to the telecopier number specified above, (ii) if given by mail, five Business Days after being deposited in the mails addressed as specified above, and (iii) if given by other means, when delivered at the address specified above, except that written notices to the Liquidity Provider pursuant to the provisions of Article II and Article III hereof shall not be effective until received by the Liquidity Provider. A copy of all notices delivered hereunder to either party shall in addition be delivered to each of the parties to the Participation Agreements at their respective addresses set forth therein.

Section 7.03 No Waiver; Remedies. No failure on the part of the Liquidity Provider to exercise, and no delay in exercising, any right under this Agreement shall operate as a waiver thereof; nor shall any single or partial exercise of any right under this Agreement preclude any other or further exercise thereof or the exercise of any other right. The remedies herein provided are cumulative and not exclusive of any remedies provided by law.

Section 7.04 Further Assurances. The Borrower agrees to do such further acts and things and to execute and deliver to the Liquidity Provider such additional assignments, agreements, powers and instruments as the Liquidity Provider may reasonably require or deem advisable to carry into effect the purposes of this Agreement and the other Operative Agreements or to better assure and confirm unto the Liquidity Provider its rights, powers and remedies hereunder and under the other Operative Agreements.

Section 7.05 Indemnification; Survival of Certain Provisions. The Liquidity Provider shall be indemnified hereunder to the extent and in the manner described in Section 8.1 of the Participation Agreements. In addition, the Borrower agrees to indemnify, protect, defend and hold harmless the Liquidity Provider from, against and in respect of, and shall pay on demand, all Expenses of any kind or nature whatsoever (other than any Expenses of the nature described in Section 3.01, 3.02 or 7.07 hereof or in the Fee Letter applicable to this Agreement (regardless of whether indemnified against pursuant to said Sections or in such Fee Letter)), that may be imposed, incurred by or asserted against any Liquidity Indemnitee, in any way relating to, resulting from, or arising out of or in connection with any action, suit or proceeding by any third party against such Liquidity Indemnitee and relating to this Agreement, the Fee Letter applicable to this Agreement, the Intercreditor Agreement or any Financing Agreement; provided, however, that the Borrower shall not be required to indemnify, protect, defend and hold harmless any Liquidity Indemnitee in respect of any Expense of such Liquidity Indemnitee to the extent such Expense is (i) attributable to the gross negligence or willful misconduct of such Liquidity

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Indemnitee or any other Liquidity Indemnitee, (ii) ordinary and usual operating overhead expense, or (iii) attributable to the failure by such Liquidity Indemnitee or any other Liquidity Indemnitee to perform or observe any agreement, covenant or condition on its part to be performed or observed in this Agreement, the Intercreditor Agreement, the Fee Letter applicable to this Agreement or any other Operative Agreement to which it is a party. The indemnities contained in Section 8.1 of the Participation Agreements, and the provisions of Sections 3.01, 3.02, 3.03, 3.09, 7.05 and 7.07 hereof, shall survive the termination of this Agreement.

Section 7.06 Liability of the Liquidity Provider. (a) Neither the Liquidity Provider nor any of its officers, employees, directors or Affiliates shall be liable or responsible for: (i) the use which may be made of the Advances or any acts or omissions of the Borrower or any beneficiary or transferee in connection therewith; (ii) the validity, sufficiency or genuineness of documents, or of any endorsement thereon, even if such documents should prove to be in any or all respects invalid, insufficient, fraudulent or forged; or (iii) the making of Advances by the Liquidity Provider against delivery of a Notice of Borrowing and other documents which do not comply with the terms hereof; provided, however, that the Borrower shall have a claim against the Liquidity Provider, and the Liquidity Provider shall be liable to the Borrower, to the extent of any damages suffered by the Borrower which were the result of (A) the Liquidity Provider’s willful misconduct or negligence in determining whether documents presented hereunder comply with the terms hereof, or (B) any breach by the Liquidity Provider of any of the terms of this Agreement, including, but not limited to, the Liquidity Provider’s failure to make lawful payment hereunder after the delivery to it by the Borrower of a Notice of Borrowing strictly complying with the terms and conditions hereof. In no event, however, shall the Liquidity Provider be liable on any theory of liability for any special, indirect, consequential or punitive damages (including, without limitation, any loss of profits, business or anticipated savings).

(b) Neither the Liquidity Provider nor any of its officers, employees, directors or Affiliates shall be liable or responsible in any respect for (i) any error, omission, interruption or delay in transmission, dispatch or delivery of any message or advice, however transmitted, in connection with this Agreement or any Notice of Borrowing delivered hereunder, or (ii) any action, inaction or omission which may be taken by it in good faith, absent willful misconduct or gross negligence (in which event the extent of the Liquidity Provider’s potential liability to the Borrower shall be limited as set forth in the immediately preceding paragraph), in connection with this Agreement or any Notice of Borrowing.

Section 7.07 Costs, Expenses and Taxes. The Borrower agrees to pay, or cause to be paid (A) on the Effective Date and on such later date or dates on which the Liquidity Provider shall make demand, all reasonable out-of-pocket costs and expenses (including, without limitation, the reasonable fees and expenses of outside counsel for the Liquidity Provider) of the Liquidity Provider in connection with the preparation, negotiation, execution, delivery, filing and recording of this Agreement, any other Operative Agreement and any other documents which may be delivered in connection with this Agreement and (B) on demand, all reasonable costs and expenses (including reasonable counsel fees and expenses) of the Liquidity Provider in connection with (i) the enforcement of this Agreement or any other Operative Agreement, (ii) the modification or amendment of, or supplement to, this Agreement or any other Operative Agreement or such other documents which may be delivered in connection herewith or therewith (whether or not the same shall become effective) or any waiver or consent thereunder (whether

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or not the same shall be effective), (iii) the replacement of this Agreement by a Replacement Liquidity Facility pursuant to Section 3.5(e)(i) of the Intercreditor Agreement or (iv) any action or proceeding relating to any order, injunction, or other process or decree restraining or seeking to restrain the Liquidity Provider from paying any amount under this Agreement, the Intercreditor Agreement or any other Operative Agreement or otherwise affecting the application of funds in the Class AA Cash Collateral Account. In addition, the Borrower shall pay any and all recording, stamp and other similar taxes and fees payable or determined to be payable in connection with the execution, delivery, filing and recording of this Agreement, any other Operative Agreement and such other documents, and agrees to hold the Liquidity Provider harmless from and against any and all liabilities with respect to or resulting from any delay in paying or omission to pay such taxes or fees.

Section 7.08 Binding Effect; Participations. (a) This Agreement shall be binding upon and inure to the benefit of the Borrower and the Liquidity Provider and their respective successors and assigns, except that neither the Liquidity Provider (except as otherwise provided in this Section 7.08 and in Section 3.5(l) of the Intercreditor Agreement) nor (except as contemplated by Section 3.08) the Borrower shall have the right to assign its rights or obligations hereunder or any interest herein without the prior written consent of the other party, subject to the requirements of Section 7.08(b). The Liquidity Provider may grant participations herein or in any of its rights hereunder (including, without limitation, funded participations and participations in rights to receive interest payments hereunder) and under the other Operative Agreements to such Persons (other than United and its Affiliates) as the Liquidity Provider may in its sole discretion select, subject to the requirements of Section 7.08(b). No such granting of participations by the Liquidity Provider, however, will relieve the Liquidity Provider of its obligations hereunder. In connection with any participation or any proposed participation, the Liquidity Provider may disclose to the participant or the proposed participant any information that the Borrower is required to deliver or to disclose to the Liquidity Provider pursuant to this Agreement. The Borrower acknowledges and agrees that the Liquidity Provider’s source of funds may derive in part from its participants. Accordingly, references in this Agreement and the other Operative Agreements to determinations, reserve, capital adequacy and liquidity coverage requirements, increased costs, reduced receipts, additional amounts due pursuant to Section 3.03 and the like as they pertain to the Liquidity Provider shall be deemed also to include those of each of its participants that are banks (subject, in each case, to the maximum amount that would have been incurred by or attributable to the Liquidity Provider directly if the Liquidity Provider, rather than the participant, had held the interest participated).

(b) If, pursuant to subsection (a) above, the Liquidity Provider sells any participation in this Agreement to any bank or other entity (each, a “Transferee”), then, concurrently with the effectiveness of such participation, the Transferee shall (i) represent to the Liquidity Provider (for the benefit of the Liquidity Provider and the Borrower) either (A) that it is incorporated under the laws of the United States or a state thereof or (B) that under applicable law and treaties, no taxes will be required to be withheld with respect to any payments to be made to such Transferee in respect of this Agreement, (ii) furnish to the Liquidity Provider and the Borrower either (x) a statement that it is incorporated under the laws of the United States or a state thereof or (y) if it is not so incorporated, two copies of a properly completed United States Internal Revenue Service Form W-8ECI, Form W-8BEN-E or Form W-9, as appropriate, or other applicable form, certificate or document prescribed by the Internal Revenue Service certifying, in

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each case, such Transferee’s entitlement to a complete exemption from United States federal withholding tax in respect to any and all payments to be made hereunder, and (iii) agree (for the benefit of the Liquidity Provider and the Borrower) to provide the Liquidity Provider and the Borrower a new Form W-8ECI, Form W-8BEN-E or Form W-9, as appropriate, (A) on or before the date that any such form expires or becomes obsolete or (B) after the occurrence of any event requiring a change in the most recent form previously delivered by it and prior to the immediately following due date of any payment by the Borrower hereunder, certifying in the case of a Form W-8ECI, Form W-8BEN-E or Form W-9 that such Transferee is entitled to a complete exemption from United States federal withholding tax on payments under this Agreement. Unless the Borrower has received forms or other documents reasonably satisfactory to it (and required by applicable law) indicating that payments hereunder are not subject to United States federal withholding tax, the Borrower will withhold taxes as required by law from such payments at the applicable statutory rate.

(c) Notwithstanding the other provisions of this Section 7.08, the Liquidity Provider may assign and pledge all or any portion of the Advances owing to it to any Federal Reserve Bank or the United States Treasury as collateral security pursuant to Regulation A of the Board of Governors of the Federal Reserve System and any Operating Circular issued by such Federal Reserve Bank, provided that any payment in respect of such assigned Advances made by the Borrower to the Liquidity Provider in accordance with the terms of this Agreement shall satisfy the Borrower’s obligations hereunder in respect of such assigned Advance to the extent of such payment. No such assignment shall release the Liquidity Provider from its obligations hereunder.

Section 7.09 Severability. Any provision of this Agreement which is prohibited, unenforceable or not authorized in any jurisdiction shall, as to such jurisdiction, be ineffective to the extent of such prohibition, unenforceability or non-authorization without invalidating the remaining provisions hereof or affecting the validity, enforceability or legality of such provision in any other jurisdiction.

Section 7.10 GOVERNING LAW. THIS AGREEMENT SHALL BE GOVERNED BY, AND CONSTRUED IN ACCORDANCE WITH, THE LAW OF THE STATE OF NEW YORK.

Section 7.11 Submission to Jurisdiction; Waiver of Jury Trial; Waiver of Immunity. (a) Each of the parties hereto hereby irrevocably and unconditionally:

(i) submits for itself and its property in any legal action or proceeding relating to this Agreement or any other Operative Agreement, or for recognition and enforcement of any judgment in respect hereof or thereof, to the nonexclusive general jurisdiction of the courts of the State of New York, the courts of the United States of America for the Southern District of New York, and the appellate courts from any thereof;

(ii) consents that any such action or proceeding may be brought in such courts, and waives any objection that it may now or hereafter have to the venue of any such action or proceeding in any such court or that such action or proceeding was brought in an inconvenient court and agrees not to plead or claim the same;

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(iii) agrees that service of process in any such action or proceeding may be effected by mailing a copy thereof by registered or certified mail (or any substantially similar form of mail), postage prepaid, to each party hereto at its address set forth in Section 7.02 hereof, or at such other address of which the Liquidity Provider shall have been notified pursuant thereto; and

(iv) agrees that nothing herein shall affect the right to effect service of process in any other manner permitted by law or shall limit the right to sue in any other jurisdiction.

(b) THE BORROWER AND THE LIQUIDITY PROVIDER EACH HEREBY AGREE TO WAIVE THEIR RESPECTIVE RIGHTS TO A JURY TRIAL OF ANY CLAIM OR CAUSE OF ACTION BASED UPON OR ARISING OUT OF THIS AGREEMENT OR ANY DEALINGS BETWEEN THEM RELATING TO THE SUBJECT MATTER OF THIS AGREEMENT AND THE RELATIONSHIP THAT IS BEING ESTABLISHED, including, without limitation, contract claims, tort claims, breach of duty claims and all other common law and statutory claims. The Borrower and the Liquidity Provider each warrant and represent that it has reviewed this waiver with its legal counsel, and that it knowingly and voluntarily waives its jury trial rights following consultation with such legal counsel. THIS WAIVER IS IRREVOCABLE, AND CANNOT BE MODIFIED EITHER ORALLY OR IN WRITING, AND THIS WAIVER SHALL APPLY TO ANY SUBSEQUENT AMENDMENTS, RENEWALS, SUPPLEMENTS OR MODIFICATIONS TO THIS AGREEMENT.

(c) To the extent that the Liquidity Provider or any of its properties has or may hereafter acquire any right of immunity, whether characterized as sovereign immunity or otherwise, and whether under the United States Foreign Sovereign Immunities Act of 1976 (or any successor legislation) or otherwise, from any legal proceedings, whether in the United States or elsewhere, to enforce or collect upon this Agreement, including, without limitation, immunity from suit or service of process, immunity from jurisdiction or judgment of any court or tribunal or execution of a judgment, or immunity of any of its property from attachment prior to any entry of judgment, or from attachment in aid of execution upon a judgment, the Liquidity Provider hereby irrevocably and expressly waives any such immunity, and agrees not to assert any such right or claim in any such proceeding, whether in the United States or elsewhere.

Section 7.12 Execution in Counterparts. This Agreement may be executed in any number of counterparts and by different parties hereto on separate counterparts, each of which counterparts, when so executed and delivered, shall be deemed to be an original and all of which counterparts, taken together, shall constitute but one and the same Agreement.

Section 7.13 Entirety. This Agreement, the Intercreditor Agreement and the other Operative Agreements to which the Liquidity Provider is a party constitute the entire agreement of the parties hereto with respect to the subject matter hereof and supersedes all prior understandings and agreements of such parties.

Section 7.14 Headings. Section headings in this Agreement are included herein for convenience of reference only and shall not constitute a part of this Agreement for any other purpose.

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Section 7.15 Transfer. The Liquidity Provider hereby acknowledges and consents to the Transfer contemplated by the Assignment and Assumption Agreement. Upon the occurrence of the Transfer contemplated by the Assignment and Assumption Agreement, the Class AA Trustee shall (without any further act) be deemed to have transferred all of its rights, title, interest and obligations in, to and under this Agreement to the trustee of the Successor Trust and the trustee of the Successor Trust shall (without any further act) be deemed to have assumed all of the Class AA Trustee’s rights, title, interest and obligations in, to and under this Agreement, and, thereafter, each reference to the Borrower herein and in the other Operative Agreements shall be deemed a reference to the trustee of the Successor Trust.

Section 7.16 LIQUIDITY PROVIDER’S OBLIGATION TO MAKE ADVANCES. EXCEPT AS EXPRESSLY SET FORTH IN THIS AGREEMENT, THE OBLIGATIONS OF THE LIQUIDITY PROVIDER TO MAKE ADVANCES HEREUNDER, AND THE BORROWER’S RIGHTS TO DELIVER NOTICES OF BORROWING REQUESTING THE MAKING OF ADVANCES HEREUNDER, SHALL BE UNCONDITIONAL AND IRREVOCABLE, AND SHALL BE PAID OR PERFORMED, IN EACH CASE STRICTLY IN ACCORDANCE WITH THE TERMS OF THIS AGREEMENT.

Section 7.17 Patriot Act. In compliance with the USA Patriot Act and 31 CFR Part 103.121 and, in the case of a non-U.S. entity, any other similar requirements of the relevant foreign jurisdiction, when requested the Borrower shall provide to the Liquidity Provider certain information relating to the Borrower that the Liquidity Provider may be required to obtain and keep on file, including the Borrower’s name, address and various identifying documents.

Section 7.18 Head Office Obligations. The Liquidity Provider is National Australia Bank Limited, acting through its New York branch. The Liquidity Provider hereby agrees that, notwithstanding the place of booking or its jurisdiction of incorporation or organization, the obligations of the Liquidity Provider hereunder are also the obligations of the head office of National Australia Bank Limited in Melbourne, Australia (the “Head Office”). Accordingly, any beneficiary of this Agreement will be able to proceed directly against the Head Office, if the Liquidity Provider defaults in its obligations to such beneficiary under this Agreement.

Section 7.19 Acknowledgement and Consent to Bail-In of EEA Financial Institutions. Notwithstanding anything to the contrary in this Agreement or in any other agreement, arrangement or understanding among any such parties, each party hereto acknowledges that any liability of any EEA Financial Institution arising under this Agreement, to the extent such liability is unsecured, may be subject to the write-down and conversion powers of an EEA Resolution Authority and agrees and consents to, and acknowledges and agrees to be bound by:

(a) the application of any write-down or conversion powers by an EEA Resolution Authority to any such liabilities arising hereunder which may be payable to it by any party hereto that is an EEA Financial Institution; and

(b) the effects of any Bail-in Action on any such liability, including, if applicable:

(i) a reduction, in full or in part, of any such liability;

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[Revolving Credit Agreement (2019-1AA)]

(ii) a conversion of all, or a portion of, such liability into shares or other instruments of ownership in such EEA Financial Institution, its parent undertaking, or a bridge institution and that such shares or other instruments of ownership will be accepted by it in lieu of any rights with respect to any such liability under this Agreement; or

(iii) the variation of the terms of such liability in connection with the exercise of the write-down and conversion powers of any EEA Resolution Authority.

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IN WITNESS WHEREOF, the parties have caused this Agreement to be duly executed and delivered by their respective officers thereunto duly authorized as of the date first set forth above.

Signature Page to Class AA Revolving Credit Agreement

[Revolving Credit Agreement (2019-1AA)]

SCHEDULE A

TO

REVOLVING CREDIT AGREEMENT

CERTAIN ECONOMIC TERMS

1. Applicable Margin (Unpaid Advance (including, without limitation, any Applied Special Termination Advance but excluding any Unapplied Special Termination Advance)/Applied Provider Advance): 3.25% per annum.

2. Initial Expiry Date: February 11, 2020.

3. Liquidity Event of Default Delivery Period threshold: $400,000,000.

4. Initial Maximum Commitment: $45,766,460.

5. Prospectus Supplement date: January 28, 2019.

SCHEDULE A

Page 1

[Revolving Credit Agreement (2019-1AA)]

SCHEDULE B

TO

REVOLVING CREDIT AGREEMENT

ADMINISTRATION DETAILS

Account Details:

SCHEDULE B

Page 1

[Revolving Credit Agreement (2019-1AA)]

ANNEX I

TO

REVOLVING CREDIT AGREEMENT

INTEREST ADVANCE NOTICE OF BORROWING

The undersigned, a duly authorized signatory of the undersigned borrower (the “Borrower”), hereby certifies to National Australia Bank Limited, acting through its New York branch (the “Liquidity Provider”), with reference to the Revolving Credit Agreement (2019-1AA) dated as of February 11, 2019, between the Borrower and the Liquidity Provider (the “Liquidity Agreement”; the terms defined therein and not otherwise defined herein being used herein as therein defined or referenced), that:

(1) The Borrower is the Subordination Agent under the Intercreditor Agreement.

(2) The Borrower is delivering this Notice of Borrowing for the making of an Interest Advance by the Liquidity Provider to be used, subject to clause (3)(v) below, for the payment of interest on the Class AA Certificates which was payable on                     ,              (the “Distribution Date”) in accordance with the terms and provisions of the Class AA Trust Agreement and the Class AA Certificates, which Advance is requested to be made on [                    ,             ]¹. The Interest Advance should be transferred to [name of bank/wire instructions/ABA number] in favor of account number [        ], reference [        ].

(3) The amount of the Interest Advance requested hereby (i) is $[                    ], to be applied in respect of the payment of the interest which was due and payable on the Class AA Certificates on the Distribution Date, (ii) does not include any amount with respect to the payment of principal of, or premium on, the Class AA Certificates, or principal of, or interest or premium on, the Class A Certificates or any Additional Certificates, (iii) was computed in accordance with the provisions of the Class AA Certificates, the Liquidity Agreement, the Class AA Trust Agreement and the Intercreditor Agreement (a copy of which computation is attached hereto as Schedule I), (iv) does not exceed the Maximum Available Commitment on the date hereof, (v) does not include any amount of interest which was due and payable on the Class AA Certificates on such Distribution Date but which remains unpaid due to the failure of the Depositary to pay any amount of accrued interest on the Deposits on such Distribution Date and (vi) has not been and is not the subject of a prior or contemporaneous Notice of Borrowing.

ANNEX I

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[Revolving Credit Agreement (2019-1AA)]

(4) Upon receipt by or on behalf of the Borrower of the amount requested hereby, (a) the Borrower will apply the same in accordance with the terms of Section 3.5(b) of the Intercreditor Agreement, (b) no portion of such amount shall be applied by the Borrower for any other purpose and (c) no portion of such amount until so applied shall be commingled with other funds held by the Borrower.

The Borrower hereby acknowledges that, pursuant to the Liquidity Agreement, the making of the Interest Advance as requested by this Notice of Borrowing shall automatically reduce, subject to reinstatement in accordance with the terms of the Liquidity Agreement, the Maximum Available Commitment by an amount equal to the amount of the Interest Advance requested to be made hereby as set forth in clause (i) of paragraph (3) of this Notice of Borrowing and such reduction shall automatically result in corresponding reductions in the amounts available to be borrowed pursuant to a subsequent Advance.

ANNEX I

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IN WITNESS WHEREOF, the Borrower has executed and delivered this Notice of Borrowing as of the              day of                      ,            .