<Page>

                                                                 EXHIBIT 4(b)(1)

                                                                  EXECUTION COPY

            This Trust Supplement No. 2001-1A-1, dated as of June 1, 2001
(herein called the "TRUST SUPPLEMENT"), by and among Northwest Airlines
Corporation, a Delaware corporation (the "GUARANTOR"), Northwest Airlines, Inc.,
a Minnesota corporation (the "COMPANY"), and State Street Bank and Trust Company
of Connecticut, National Association (the "TRUSTEE"), to the Pass Through Trust
Agreement, dated as of June 3, 1999, by and among the Guarantor, the Company 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
principal amount of Certificates which may be issued thereunder, has heretofore
been executed and delivered;

            WHEREAS, unless otherwise specified herein, capitalized terms used
herein without definition having the respective meanings specified heretofore in
the Basic Agreement;

            WHEREAS, the Company intends to finance the acquisition of nine new
Airbus A319-100 aircraft, three new Boeing 757-300 aircraft and two new Boeing
747-400 aircraft (the "AIRCRAFT"), as selected by the Company out of the fifteen
Airbus A319-100 aircraft, six Boeing 757-300 aircraft and two Boeing 747-400
aircraft scheduled for delivery from February 2002 through December 2002 (the
"ELIGIBLE AIRCRAFT"), either (i) through separate leveraged lease transactions,
in which case the Company will lease such aircraft (collectively, the "LEASED
AIRCRAFT") or (ii) through separate secured loan transactions, in which case the
Company will own such aircraft (collectively, the "OWNED AIRCRAFT");

            WHEREAS, in the case of each Leased Aircraft, each Owner Trustee,
acting on behalf of its respective Owner Participant, will issue, on a
non-recourse basis, Equipment Notes, among other things, to finance a portion of
the purchase price of such Leased Aircraft purchased or to be purchased by such
Owner Trustee and leased or to be leased to the Company pursuant to the related
Lease;

            WHEREAS, in the case of an Owned Aircraft, the Company will issue
Equipment Notes to finance a portion of the purchase price of such Owned
Aircraft;

            WHEREAS, pursuant to the terms and conditions of the Basic Agreement
as supplemented by this Trust Supplement (the "AGREEMENT"), the Trustee shall
purchase such Equipment Notes issued by each Owner Trustee or the Company, as
the case may be, having the same interest rate as, and final maturity dates not
later than the final Regular Distribution Date of, the Certificates issued
hereunder and shall hold such Equipment Notes in trust for the benefit of the
Certificateholders;

            WHEREAS, the Trustee hereby declares the creation of this Trust (the
"2001-1A-1 TRUST" or the "APPLICABLE TRUST") for the benefit of the Applicable
Certificateholders, and the initial Applicable Certificateholders as the
grantors of the 2001-1A-1 Trust, by their respective acceptances of the
Applicable Certificates, join in the creation of this 2001-1A-1 Trust with the
Trustee;

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                                                                               2


            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
by and among the Guarantor, 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
"Pass Through Certificates, Series 2001-1A-1" (hereinafter defined as the
"SERIES 2001-1A-1 CERTIFICATES" or the "APPLICABLE CERTIFICATES"). Each Series
2001-1A-1 Certificate represents a Fractional Undivided Interest in the
2001-1A-1 Trust created hereby.

            The terms and conditions applicable to the Series 2001-1A-1
Certificates are as follows:

            (a) The aggregate principal amount of the Series 2001-1A-1
      Certificates that shall be authenticated under the Agreement (except for
      Series 2001-1A-1 Certificates authenticated and delivered pursuant to
      Sections 3.03, 3.04 and 3.05 of the Basic Agreement) upon their initial
      issuance is $201,112,000.

            (b) The Cut-off Date is the earlier of (a) March 31, 2003 and (b)
      the date on which a Triggering Event occurs.

            (c) The Regular Distribution Dates with respect to any payment of
      Scheduled Payments means each April 1 and October 1, commencing on October
      1, 2001, until payment of all of the Scheduled Payments to be made under
      the Equipment Notes has been made.

            (d) The Special Distribution Dates are as follows: (i) when used
      with respect to the redemption or purchase of any Equipment Notes, the day
      (which shall be a Business Day) on which such redemption or purchase is
      scheduled to occur pursuant to the terms of the applicable Indenture and
      (ii) when used with respect to a Special Payment other than as described
      in clause (i) above, 15 days after the last date on which the Trustee must
      give notice pursuant to Section 4.02(c) of the Basic Agreement (or the
      next Business Day after such 15th day if such date is not a Business Day).

            (e) (i) The Series 2001-1A-1 Certificates shall be in the form
      attached hereto as Exhibit A. Each purchaser of Series 2001-1A-1
      Certificates, by its acceptance of such

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      Certificate or its interest therein, will be deemed to represent and
      warrant to and for the benefit of each Owner Participant and the Company
      that either (x) the assets of an employee benefit plan subject to Title I
      of the Employee Retirement Income Security Act of 1974, as amended
      ("ERISA"), of a plan subject to Section 4975 of the Internal Revenue Code
      of 1986, as amended (the "CODE"), of entities which may be deemed to hold
      such plans' assets, or of another employee benefit plan not subject to
      ERISA or Section 4975 of the Code (such as a governmental, church or
      non-U.S. plan) have not been used to purchase Series 2001-1A-1
      Certificates or (y) one or more prohibited transaction statutory or
      administrative exemptions applies such that the use of such plan assets to
      purchase and hold such Certificate will not constitute a non-exempt
      prohibited transaction under ERISA or Section 4975 of the Code or a
      violation under any federal, state or local law that is substantially
      similar to the provisions of Title I of ERISA or Section 4975 of the Code.

            (i) The Series 2001-1A-1 Certificates shall be Book-Entry
      Certificates and shall be subject to the conditions set forth in the
      Letter of Representations among the Guarantor, the Company and the
      Clearing Agency (the "CLEARING AGENCY") attached hereto as Exhibit B.

            (f) The Scheduled Payments of principal shall be as set forth in
      Exhibit C hereto.

            (g) The proceeds of the Series 2001-1A-1 Certificates shall be
      deposited in the Deposit Accounts and will be used in accordance with the
      Escrow Agreement and the Deposit Agreement.

            (h) When each Aircraft is delivered, either the Owner Trustee (in
      the case of a Leased Aircraft), acting on behalf of its respective Owner
      Participant, will issue on a non-recourse basis, or the Company (in the
      case of an Owned Aircraft) will issue on a recourse basis, the Equipment
      Notes, the proceeds of which shall be used, among other things, to finance
      a portion of the purchase price to such Owner Trustee or the Company, as
      the case may be, of the following Aircraft (assuming that for purposes of
      the chart below that the first 14 Eligible Aircraft scheduled for delivery
      among the 23 Eligible Aircraft are financed):

<Table>
<Caption>

       Expected Registration Number      Aircraft Type        Engine Type
       ----------------------------      -------------        -----------
<S>                                     <C>                   <C>
      N338NB........................    Airbus A319-100        CFM56-5A4
      N340NB........................    Airbus A319-100        CFM56-5A4
      N343NB........................    Airbus A319-100        CFM56-5A4
      N344NB........................    Airbus A319-100        CFM56-5A4
      N345NB........................    Airbus A319-100        CFM56-5A4
      N346NB........................    Airbus A319-100        CFM56-5A4
      N347NB........................    Airbus A319-100        CFM56-5A4
      N348NB........................    Airbus A319-100        CFM56-5A4
      N349NB........................    Airbus A319-100        CFM56-5A4
      N580NW........................    Boeing 757-300          PW2040
      N581NW........................    Boeing 757-300          PW2040
</Table>

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                                                                               4

<Table>
<Caption>

       Expected Registration Number      Aircraft Type        Engine Type
       ----------------------------      -------------        -----------
<S>                                     <C>                   <C>
      N582NW........................    Boeing 757-300          PW2040
      N675NW........................    Boeing 747-400          PW4056
      N676NW........................    Boeing 747-400          PW4056
</Table>

            (i) At the Escrow Agent's request under the Escrow Agreement, the
      Trustee shall affix the corresponding Escrow Receipt to each Series
      2001-1A-1 Certificate. In any event, any transfer or exchange of any
      Series 2001-1A-1 Certificate shall also effect a transfer or exchange of
      the related Escrow Receipt. Prior to the Final Withdrawal Date, no
      transfer or exchange of any Series 2001-1A-1 Certificate shall be
      permitted unless the corresponding Escrow Receipt is attached thereto and
      also is so transferred or exchanged. By acceptance of any Series 2001-1A-1
      Certificate to which an Escrow Receipt is attached, each Certificateholder
      of such a Series 2001-1A-1 Certificate acknowledges and accepts the
      restrictions on transfer of the Escrow Receipt set forth herein and in the
      Escrow Agreement.

            Section 1.02. INTERCREDITOR AGREEMENT. The Series 2001-1A-1
Certificates are subject to the Intercreditor Agreement, the Deposit Agreement
and the Escrow Agreement.

            Section 1.03. RANKING OF SERIES 2001-1A-1 CERTIFICATES. The Series
2001-1A-1 Certificates will be subject to the ranking and priority as set forth
in the Intercreditor Agreement.

            Section 1.04. LIQUIDITY FACILITY. Payments of interest on the Series
2001-1A-1 Certificates will be supported by a Liquidity Facility to be provided
by the Liquidity Provider for the benefit of the Applicable Certificateholders.

            Section 1.05. NO CROSS-DEFAULT OR CROSS-COLLATERALIZATION OF
EQUIPMENT NOTES. As set forth in the related Indenture, there will not be any
cross-collateralization provisions or cross-default provisions in respect of the
Equipment Notes.

                                   ARTICLE II
                             PREDELIVERY FUNDING AND
                               STATEMENT OF INTENT

            Section 2.01. PREDELIVERY FUNDING. On the date hereof, the proceeds
from the issuance of the Applicable Certificates will be deposited in the
Deposit Accounts on behalf of the Escrow Agent. Pursuant to the terms of the
Deposit Agreement and the Note Purchase Agreement, a portion of the proceeds
from the issuance of the Applicable Certificates will be withdrawn from the
Deposit Account on any date on which an Owner Trustee (in the case of a Leased
Aircraft) or the Company (in the case of an Owned Aircraft) issues Equipment
Notes with respect to an Aircraft.

            Section 2.02. STATEMENT OF INTENT. 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 Code and not as a
trust or association taxable as a corporation or a partnership. Each of the
parties hereto and each Applicable Certificateholder, or beneficial owner of an
Applicable Certificate, by its acceptance of its Applicable Certificate or a
beneficial

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interest therein, agrees to treat for all U.S. federal, state and local income
tax purposes (i) the Applicable Trust as a grantor trust and (ii) Equipment
Notes to be issued (or assumed) by an Owner Trust (in the case of a Leased
Aircraft) as indebtedness of such Owner Trust, and Equipment Notes issued by the
Company (in the case of an Owned Aircraft) as indebtedness of the Company.

            Section 2.03. ACTIVITIES OF TRUST. (a) Other than in connection with
the transactions contemplated by this Agreement or the Note Documents, the
Trustee, on behalf of the Applicable Trust, shall not (i) borrow money or issue
debt or (ii) merge with another entity, reorganize, liquidate or sell its
assets.

            (b) The activities of the Trustee engaged in, on behalf of the
Applicable Trust, shall be limited to those activities authorized by this
Agreement or the Note Documents.

                                   ARTICLE III
                                   DEFINITIONS

            Section 3.01. DEFINITIONS. (a) For all purposes of the Basic
Agreement as supplemented by this Trust Supplement, the following capitalized
terms have the following meanings:

            AIRCRAFT: Has the meaning specified in the recitals hereto.

            APPLICABLE CERTIFICATEHOLDER: Means the holder of an Applicable
      Certificate.

            APPLICABLE CERTIFICATES: As defined in Section 1.01.

            CLASS D CERTIFICATEHOLDER: Means the holder of a Class D
      Certificate.

            CLASS D CERTIFICATES: Has the meaning assigned in the Intercreditor
      Agreement.

            CLEARING AGENCY: Has the meaning specified in Section 1.01(e)
      hereof.

            CLEARING AGENCY PARTICIPANT: Means any of the participants in the
      Clearing Agency.

            CLOSING NOTICE: Has the meaning specified in the Note Purchase
      Agreement.

            CUT-OFF DATE: Has the meaning specified in Section 1.01(b).

            DEPOSIT ACCOUNT: Means an account established under Section 1.2 of
      the Deposit Agreement.

            DEPOSIT AGREEMENT: Means the Deposit Agreement dated as of June 1,
      2001 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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                                                                               6


            DEPOSIT MAKE-WHOLE AMOUNT: Has the meaning specified in the Note
      Purchase Agreement.

            DEPOSITARY: Means ABN AMRO Bank N.V., doing business through a
      United States branch and any replacement or successor therefor.

            DEPOSITS: Has the meaning specified in the Note Purchase Agreement.

            DISTRIBUTION DATE: Means any Regular Distribution Date or Special
      Distribution Date.

            ELIGIBLE AIRCRAFT: Has the meaning specified in the recitals hereto.

            ESCROW AGENT: Means initially, Wells Fargo Bank Northwest, 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 June 1, 2001 relating to the Applicable Certificates, among the
      Escrow Agent, the 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 RECEIPT: Means the receipt substantially in the form annexed
      to the Escrow Agreement representing a fractional undivided interest in
      the funds held in the Paying Agent Account (as defined in the Escrow
      Agreement).

            FINAL WITHDRAWAL: With respect to the Escrow Agreement, has the
      meaning set forth in Section 1.2 thereof.

            FINAL WITHDRAWAL DATE: Means the date on which the Final Withdrawal
      occurs.

            INTERCREDITOR AGREEMENT: Means the Intercreditor Agreement, dated as
      of the date hereof, by and among the Trustee, the Other Trustee, the
      Liquidity Providers named therein and State Street Bank and Trust Company,
      as Subordination Agent.

            LEASED AIRCRAFT: Has the meaning specified in the recitals hereto.

            LIQUIDITY FACILITY: Has the meaning specified in the Note Purchase
      Agreement.

            NOTE DOCUMENTS: With respect to any Equipment Note, means the Note
      Purchase Agreement, the related Indenture, the related Participation
      Agreement, and, if the related Aircraft is leased to the Company, the
      related Lease.

            NOTE PURCHASE AGREEMENT: Means the Note Purchase Agreement, dated as
      of the date hereof, among the Company, the Trustee, the Other Trustee,
      State Street Bank and Trust Company, as Subordination Agent, the Escrow
      Agent and the Paying Agent.

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            NOTICE OF PURCHASE WITHDRAWAL: Has the meaning specified in the Note
      Purchase Agreement.

            NOTICE OF SERIES D NON-ISSUANCE WITHDRAWAL: Has the meaning
specified in the Deposit Agreement.

            OTHER AGREEMENT: Means the Basic Agreement as supplemented by Trust
      Supplement No. 2001-1A-2 (the "2001-1A-2 TRUST SUPPLEMENT") dated the date
      hereof relating to Northwest Airlines 2001-1A-2 Pass Through Trust, by
      Trust Supplement No. 2001-1B (the "2001-1B TRUST SUPPLEMENT") dated the
      date hereof relating to the Northwest Airlines 2001-1B Pass Through Trust,
      by Trust Supplement No. 2001-1C (the "2001-1C TRUST SUPPLEMENT") dated the
      date hereof relating to the Northwest Airlines 2001-1C Pass Through Trust
      and, upon execution thereof, by Trust Supplement No. 2001-1D (the "2001-1D
      TRUST SUPPLEMENT") relating to the Northwest Airlines 2001-1D Pass Through
      Trust.

            OTHER TRUSTEE: Means the trustee under the Other Agreement, and any
      successor or other trustee appointed as provided therein.

            OWNED AIRCRAFT: Has the meaning specified in the recitals hereto.

            PARTICIPATION AGREEMENT: Has the meaning specified in the Note
      Purchase Agreement.

            PAYING AGENT: Means State Street Bank and Trust Company.

            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 in respect of such Applicable Certificates or in respect
      of Deposits relating to the Applicable Trust other than payments made in
      respect of interest or premium thereon or reimbursement of any costs or
      expenses incurred in connection therewith. The Pool Balance as of any
      Distribution Date will 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 Prospectus Supplement dated May 22,
      2001, relating to the offering of the Class A-1 Certificates, the Class
      A-2 Certificates, the Class B Certificates and the Class C Certificates
      (each as defined in the Intercreditor Agreement).

            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 other
      Trust Property and the distribution thereof to be made on that date.

            RECEIPTHOLDER: Has the meaning specified in the Escrow Agreement.

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                                                                               8


            RECORD DATE: Means the fifteenth day preceding any Distribution Date
      on which the Applicable Certificateholders are determined for purposes of
      the distribution which will occur on such Distribution Date.

            SCHEDULED CLOSING DATE: Has the meaning specified in the Note
      Purchase Agreement.

            SCHEDULED PAYMENT: Has the meaning specified in the Intercreditor
      Agreement.

            SERIES D NON-ISSUANCE WITHDRAWAL: Has the meaning specified in the
      Note Purchase Agreement.

            SPECIAL PAYMENT: Means any payment (other than a Scheduled Payment)
      in respect of, or any proceeds of, any Equipment Note or Trust Indenture
      Estate (as defined in each Indenture) or Special Redemption Premium.

            SPECIAL REDEMPTION PREMIUM: Means the Deposit Make-Whole Amount
      payable by the Company in respect of the Final Withdrawal or Series D
      Non-Issuance Withdrawal pursuant to the Note Purchase Agreement.

            TRUST PROPERTY: Means (i) the Equipment Notes held as the property
      of the Applicable Trust and, subject to the Intercreditor Agreement, all
      monies at any time paid thereon and all monies due and to become due
      thereunder, (ii) the rights of the Applicable Trust under the Escrow
      Agreement to request the Escrow Agent to withdraw from the Deposit
      Accounts funds sufficient to enable the Applicable Trust to purchase
      Equipment Notes on the delivery of an Aircraft, (iii) funds from time to
      time deposited in the Certificate Account and the Special Payments
      Account, and (iv) all rights of the Applicable Trust and the Trustee, on
      behalf of the Applicable Trust, under the Intercreditor Agreement, the
      Note Purchase Agreement and the Liquidity Facility, including, without
      limitation, the rights of the Applicable Trust to acquire Equipment Notes
      under the Note Purchase Agreement, all rights to receive certain payments
      under such documents, and all monies paid to the Trustee on behalf of the
      Applicable Trust pursuant to the Intercreditor Agreement or the Liquidity
      Facility.

            TRUSTS: Means, collectively, the Northwest Airlines 2001-1 Pass
      Through Trusts to be formed pursuant to the Basic Agreement, as
      supplemented by this Trust Supplement and the Other Agreement.

            UNDERWRITERS: Means the several Underwriters named in and who are
      parties to the Underwriting Agreement.

            UNDERWRITING AGREEMENT: Means the Underwriting Agreement dated May
      22, 2001 by and among the Company, the Guarantor, Salomon Smith Barney
      Inc., J.P. Morgan Securities Inc., Credit Suisse First Boston Corporation,
      Deutsche Banc Alex. Brown Inc., Morgan Stanley & Co. Incorporated and U.S.
      Bancorp Piper Jaffray Inc.

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            Section 3.02. OTHER. (a) For purposes of the Applicable Trust, "PTC
Event of Default," as used in the Basic Agreement, shall have the meaning set
forth in the Intercreditor Agreement.

            (b) With respect to the Applicable Trust, the definition of the term
"Specified Investments" in the Basic Agreement is amended by adding the
following sentence at the end of such definition:

            "State Street Bank and Trust Company of Connecticut, National
Association, in acting as Pass Through Trustee is hereby authorized, in making
or disposing of any investment described herein, to deal with itself (in its
individual capacity) or with any one or more of its affiliates, whether it or
such affiliate is acting as an agent of the Pass Through Trustee or for any
third person or dealing as principal for its own account."

                                   ARTICLE IV
                                   THE TRUSTEE

            Section 4.01. DELIVERY OF DOCUMENTS; DELIVERY DATES. (a) The Trustee
is hereby directed (i) to execute and deliver the Intercreditor Agreement, the
Escrow Agreement and the Note Purchase Agreement, 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 Note
Purchase Agreement. Except as provided in Sections 3.03, 3.04, 3.05 and 3.09 of
the Basic Agreement, the Trustee shall not execute, authenticate or deliver
Applicable Certificates in excess of the aggregate amount specified in this
paragraph.

            (b) On or 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 two Business
Days prior to a Scheduled Closing Date as to which such Closing Notice relates
(the "APPLICABLE DELIVERY 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 all principal
amounts from one or more Deposit Accounts on the Applicable Delivery 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 the
amount withdrawn from such Deposit Account or Accounts in an amount equal in the
aggregate to the purchase price of such Equipment Notes to or on behalf of the
Owner Trustee or the Company, as the case may be, issuing such Equipment Notes,
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 3 of the Note Purchase Agreement, 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

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                                                                              10


Applicable Participation Agreement. If at any time prior to the Applicable
Delivery Date, the Trustee receives a notice of postponement pursuant to Section
2(e) or 2(f) of the Note Purchase Agreement, 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 Account or Accounts on
such Applicable Delivery Date. Upon satisfaction of the conditions specified in
the Note Purchase Agreement and the Applicable Participation Agreement, the
Trustee shall purchase the applicable Equipment Notes with the proceeds of the
withdrawals from one or more Deposit Accounts made on the Applicable Delivery
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 Account or
Accounts in excess of the purchase price of the Equipment Notes or to the extent
not applied on the Applicable Delivery Date to the purchase price of the
Equipment Notes, shall be re-deposited by the Trustee with the Depositary on the
Applicable Delivery Date in accordance with the terms of the Deposit Agreement.

            (c) Any Closing Notice delivered by the Company in respect of an
Airbus A319-100 Aircraft or a Boeing 757-300 Aircraft may specify therein that a
Series D Non-Issuance Withdrawal will be required under the Escrow Agreement, in
which case such Closing Notice shall comply with Section 2(b)(vii) of the Note
Purchase Agreement. Upon receipt of such a Closing Notice, the Trustee shall (as
and when specified in the Closing Notice) instruct the Escrow Agent to provide a
Notice of Series D Non-Issuance Withdrawal to the Depositary requesting (i) the
withdrawal of all principal amounts from one or more Deposit Accounts on the
date specified in such Closing Notice (together with accrued interest to such
specified date on the amounts so withdrawn and not redeposited pursuant to
Section 2.4 of the Deposit Agreement) in accordance with and to the extent
permitted by the terms of the Escrow Agreement and the Deposit Agreement and
(ii) the payment to the Paying Agent (for payment to the Receiptholders in
accordance with the Escrow Agreement) of all or a portion of the amounts
withdrawn from such Deposit Account or Accounts in an amount equal to the amount
described in such Closing Notice. If at any time prior to the Applicable
Delivery Date the Trustee receives a notice of postponement pursuant to Section
2(e) or 2(f) of the Note Purchase Agreement, then the Trustee shall give the
Depositary (with a copy to the Escrow Agent) a notice of cancellation of such
Notice of Series D Non-Issuance Withdrawal relating to such Deposit Account or
Accounts. Amounts withdrawn from such Deposit Account or Accounts in excess of
the amount specified in the Closing Notice for payment to Receiptholders or, to
the extent not distributed to the Receiptholders on the date specified in the
Closing Notice, shall be redeposited by the Trustee with the Depositary in
accordance with the terms of the Deposit Agreement. Upon receipt of a Closing
Notice specifying the requirement for a Series D Non-Issuance Withdrawal, the
Trustee shall also make a demand upon the Company for an amount equal to the
Special Redemption Premium, such payment to be made on the date specified in
such Closing Notice as the date for payment by the Depositary of funds pursuant
to the Series D Non-Issuance Withdrawal.

            Section 4.02. WITHDRAWAL OF DEPOSITS. If any Deposits remain
outstanding on the Business Day next succeeding the Cut-off Date, (i) the
Trustee shall give the Escrow Agent notice that the Trustee's obligation to
purchase Equipment Notes under the Note Purchase Agreement 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") and (ii) the Trustee will make a demand upon the
Company for an amount

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                                                                              11


equal to the Special Redemption Premium, such payment to be made on the Final
Withdrawal Date.

            Section 4.03. THE TRUSTEE. (a) Subject to Section 4.04 of this Trust
Supplement and Section 7.14 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 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.

            (b) Except as herein otherwise provided, 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 Basic
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 Basic
Agreement, upon the effectiveness thereof, as fully to all intents as if the
same were herein set forth at length.

            Section 4.04. 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 and the Note Documents to which it is a
      party (collectively, the "TRUSTEE AGREEMENTS") and has taken all necessary
      action to authorize the execution, delivery and performance by it of the
      Trustee Agreements;

            (b) the execution, delivery and performance by the Trustee of the
      Trustee Agreements (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 the
      Trustee Agreements 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

<Page>
                                                                              12


            (d) each Trustee Agreement has 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 agreement of the Trustee,
      enforceable against it in accordance with its 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 4.05. TRUSTEE LIENS. The Trustee in its individual capacity
agrees, in addition to the agreements contained in Section 7.16 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 Note Purchase Agreement.

                                   ARTICLE V
                             SUPPLEMENTAL AGREEMENT

            Section 5.01. SUPPLEMENTAL AGREEMENTS. (a) For purposes of this
Trust, Section 9.01 and 9.02 of the Basic Agreement shall be amended to read as
follows:

            "Section 9.01. SUPPLEMENTAL AGREEMENTS WITHOUT CONSENT OF APPLICABLE
      CERTIFICATEHOLDERS. Without the consent of the Applicable
      Certificateholders, the Guarantor and the Company may, and the Trustee
      (subject to Section 9.03) shall, at any time and from time to time, enter
      into one or more agreements supplemental hereto or, if applicable, to the
      Deposit Agreements, the Escrow Agreements, the Intercreditor Agreement,
      the Note Purchase Agreement or any Liquidity Facility, for any of the
      following purposes:

                  (1) to provide for the formation of a Trust, the issuance of a
            series of certificates and the other matters contemplated by Section
            2.01(b); or

                  (2) to evidence the succession of another corporation to the
            Company or the Guarantor and the assumption by any such successor of
            the covenants of the Company or the Guarantor herein contained or
            contained in the Note Purchase Agreement; or

                  (3) to add to the covenants of the Guarantor or the Company
            for the benefit of the Certificateholders of any series, or to
            surrender any right or power conferred upon the Guarantor or the
            Company in this Agreement, the Intercreditor Agreement, the Note
            Purchase Agreement or any Liquidity Facility; or

                  (4) except where Certificateholder consent is required by
            Sections 9.02(1) - 9.02(6) and as described below, to correct or
            supplement any provision in this Agreement, the Deposit Agreements,
            the Escrow Agreements, the Intercreditor Agreement, the Note
            Purchase Agreement or any Liquidity Facility which may be defective
            or inconsistent with any other provision herein or in any Trust
            Supplement or to make any other provisions with respect to matters
            or questions arising under this Agreement, the Deposit Agreements,
            the Escrow

<Page>
                                                                              13


            Agreements, the Intercreditor Agreement, the Note Purchase Agreement
            or any Liquidity Facility provided that any such action shall not
            adversely affect the interests of the Certificateholders of any
            series; or to cure any ambiguity or correct any mistake in this
            Agreement, the Deposit Agreements, the Escrow Agreements, the
            Intercreditor Agreement, the Note Purchase Agreement or any
            Liquidity Facility; or

                  (5) to comply with any requirement of the SEC, any applicable
            law, rules or regulations of any exchange or quotation system on
            which the Applicable Certificates are listed, or any regulatory
            body; or

                  (6) to modify, eliminate or add to the provisions of this
            Agreement, the Deposit Agreements, the Escrow Agreements, the
            Intercreditor Agreement, the Note Purchase Agreement or any
            Liquidity Facility to such extent as shall be necessary to continue
            the qualification of this Agreement (including any supplemental
            agreement) under the Trust Indenture Act, or under any similar
            Federal statute hereafter enacted, and to add to this Agreement, the
            Deposit Agreements, the Escrow Agreements, the Intercreditor
            Agreement, the Note Purchase Agreement or any Liquidity Facility
            such other provisions as may be expressly permitted by the Trust
            Indenture Act, excluding, however, the provisions referred to in
            Section 316(a)(2) of the Trust Indenture Act as in effect at the
            date as of which this instrument was executed or any corresponding
            provision in any similar Federal statute hereafter enacted; or

                  (7) to evidence and provide for the acceptance of appointment
            under this Agreement, the Deposit Agreements, the Escrow Agreements,
            the Intercreditor Agreement, the Note Purchase Agreement or any
            Liquidity Facility by a successor Trustee with respect to one or
            more Trusts and to add to or change any of the provisions of this
            Agreement, the Deposit Agreements, the Escrow Agreements, the
            Intercreditor Agreement, the Note Purchase Agreement or any
            Liquidity Facility as shall be necessary to provide for or
            facilitate the administration of the Trusts hereunder and thereunder
            by more than one Trustee, pursuant to the requirements of Section
            7.09; or

                  (8) to make any other amendments or modifications hereto,
            provided such amendments or modifications shall only apply to
            Certificates of one or more series to be thereafter issued."

            "Section 9.02. SUPPLEMENTAL AGREEMENTS WITH CONSENT OF
      CERTIFICATEHOLDERS. With respect to each separate Trust and the series of
      Certificates relating thereto, with the consent of the Certificateholders
      holding Certificates of any series evidencing Fractional Undivided
      Interests aggregating not less than a majority in interest in such Trust,
      by Act of said Certificateholders delivered to the Guarantor, the Company
      and the Trustee, the Guarantor and the Company may (with the consent of
      the Owner Trustee, if any, relating to such Certificates, which consent
      shall not be unreasonably withheld), and the Trustee (subject to Section
      9.03) shall, enter into an agreement or agreements supplemental hereto for
      the purpose of adding any provisions to or changing in any manner or

<Page>
                                                                              14


      eliminating any of the provisions of this Agreement, the Deposit
      Agreements, the Escrow Agreements, the Intercreditor Agreement, the Note
      Purchase Agreement or any Liquidity Facility to the extent applicable to
      such Certificateholders or of modifying in any manner the rights and
      obligations of such Certificateholders under this Agreement, the Deposit
      Agreements, the Escrow Agreements, the Intercreditor Agreement, the Note
      Purchase Agreement or any Liquidity Facility; PROVIDED, HOWEVER, that no
      such supplemental agreement shall, without the consent of the
      Certificateholder of each Outstanding Certificate affected thereby:

                  (1) reduce in any manner the amount of, or delay the timing
            of, any receipt by the Trustee of payments on the Equipment Notes or
            other Trust Property held in such Trust or distributions that are
            required to be made herein on any Certificate of such series, or
            change any date of payment of any Certificate of such series, or
            change the place of payment where, or the coin or currency in which,
            any Certificate of such series is payable, or impair the right to
            institute suit for the enforcement of any such payment or
            distribution on or after the Regular Distribution Date or Special
            Distribution Date applicable thereto; or

                  (2) permit the disposition of any Equipment Note in the Trust
            Property of such Trust except as permitted by this Agreement, or
            otherwise deprive such Certificateholder of the benefit of the
            ownership of the Equipment Notes in such Trust; or

                  (3) alter the priority of distributions specified in the
            Intercreditor Agreement; or

                  (4) reduce the percentage of the aggregate Fractional
            Undivided Interests of such Trust which is required for any such
            supplemental agreement, or reduce such percentage required for any
            waiver (of compliance with certain provisions of this Agreement or
            certain defaults hereunder and their consequences) provided for in
            this Agreement; or

                  (5) modify any of the provisions of this Section or Section
            6.05, except to increase any such percentage or to provide that
            certain other provisions of this Agreement cannot be modified or
            waived without the consent of the Certificateholder of each
            Certificate or such series affected thereby.

            It shall not be necessary for any Act of such Certificateholders
      under this Section to approve the particular form of any proposed
      supplemental agreement, but it shall be sufficient if such Act shall
      approve the substance thereof."

            (b) Any supplemental agreement may not adversely affect the status
of the Applicable Trust for U.S. federal income tax purposes, as either (i) a
grantor trust under Subpart E, Part I of Subchapter J of Chapter 1 of Subtitle A
of the Code or (ii) a partnership.

<Page>
                                                                              15


                                   ARTICLE VI
                 DISTRIBUTIONS; STATEMENT TO CERTIFICATEHOLDERS

            Section 6.01. ADDITIONS TO ARTICLE IV OF THE BASIC AGREEMENT. In
addition to the provisions of Article IV of the Basic Agreement, the following
provisions shall apply to the Applicable Trust:

            (a) Upon the payment of Special Redemption Premium to the Trustee
      under the Note Purchase Agreement, the Trustee, upon receipt thereof,
      shall immediately deposit the aggregate amount of such Special Redemption
      Premium in the Special Payments account;

            (b) The distribution of amounts of Special Redemption Premium as
      provided for in Section 4.02(b) of the Basic Agreement shall be on the
      Special Distribution Date with respect to such Special Payment or as soon
      thereafter as the Trustee has confirmed receipt of the related Special
      Redemption Premium;

            (c) In the event of the payment of a Special Redemption Premium by
      the Company to the Trustee under the Note Purchase Agreement, the notice
      provided for in Section 4.02(c) of the Basic Agreement shall be mailed,
      together with the notice by the Paying Agent under Section 2.6 of the
      Escrow Agreement, not less that 15 days prior to the Special Distribution
      Date for such amount, which Special Distribution Date shall be the Final
      Withdrawal Date or date of payment of the Series D Non-Issuance
      Withdrawal, as the case may be; and

            (d) The last sentence of the first paragraph of Section 4.02(c) of
      the Basic Agreement shall apply equally if the amount of Special
      Redemption Premium, if any, has not been calculated at the time the
      Trustee mails notice of a Special Payment.

            Section 6.02. STATEMENTS TO APPLICABLE CERTIFICATEHOLDERS; FEDERAL
INCOME TAX REPORTING. (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, including any
Special Redemption Premium, reflecting in part the information provided by the
Paying Agent under the Escrow Agreement). Such statement shall set forth (per
$1,000 face amount Applicable Certificate as to (i), (ii), (iii), (iv) and (v)
below) the following information:

            (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 the Special
      Redemption Premium), if any;

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

<Page>
                                                                              16


            (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 Deposits; and

            (vi) the Pool Balance and the Pool Factor.

            With respect to the Applicable Certificates registered in the name
of a Clearing Agency, on the Record Date prior to each Distribution 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 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) of this Section 6.02 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 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 6.02(a)
hereof.

            (c) Promptly following (i) the Cut-off Date, if there has been any
change in the information set forth in clauses (x) and (y) below from that set
forth in page S-34 of the Prospectus Supplement, and (ii) any early redemption
or purchase 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 Factors for
each subsequent Regular Distribution Date following the Cut-off Date and (y) the
expected principal distribution 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
Cut-off 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.

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                                                                              17


            (d) Unless and until required otherwise by applicable authority, the
Trustee shall treat the Applicable Trust as a "grantor trust" under Subpart E,
Part I, Subchapter J of Chapter 1 of the Code, and shall file annually with the
Internal Revenue Service Form 1041, indicating the name and address of the
Applicable Trust and otherwise completed in blank, with attached statements
identifying each Applicable Certificateholder and its pro rata share of the
income and expenses of the Applicable Trust for the applicable portion of the
preceding calendar year, on the cash or accrual method, as the case may be, and
shall furnish each Applicable Certificateholder with a copy of its statement at
the time and in the manner required by the Code.

            (e) This Section 6.02 supersedes and replaces Section 4.03 of the
Basic Agreement.

                                   ARTICLE VII
                                     DEFAULT

            Section 7.01. PURCHASE RIGHTS OF CERTIFICATEHOLDERS. By acceptance
of its Applicable Certificate, each Applicable Certificateholder agrees that,
after the occurrence and during the continuation of a Triggering Event,

            (a) if the Class A-2 Trustee is then the Controlling Party, each
      Applicable Certificateholder shall have the right to purchase, for the
      purchase price set forth in the Class A-2 Trust Agreement, all, but not
      less than all, of the Class A-2 Certificates upon ten days' prior written
      notice to the Class A-2 Trustee and each other Applicable
      Certificateholder, PROVIDED that (i) if prior to the end of such --------
      ten-day period any other Applicable Certificateholder notifies such
      purchasing Applicable Certificateholder that such other Applicable
      Certificateholder wants to participate in such purchase, then such other
      Applicable Certificateholder may join with the purchasing Applicable
      Certificateholder to purchase all, but not less than all, of the Class A-2
      Certificates PRO RATA based on the fractional undivided interest in the
      Applicable Trust held by each such Applicable Certificateholder and (ii)
      if prior to the end of such ten-day period any other Applicable
      Certificateholder fails to notify the purchasing Applicable
      Certificateholder of such other Applicable Certificateholder's desire to
      participate in such purchase, then such other Applicable Certificateholder
      shall lose its right to purchase the Class A-2 Certificates pursuant to
      this Section 7.01(a); and

            (b) if the Trustee is then the Controlling Party, each Class A-2
      Certificateholder shall have the right to purchase all, but not less than
      all, of the Applicable Certificates upon ten days' prior written notice to
      the Trustee and each other Class A-2 Certificateholder, PROVIDED that (i)
      if prior to the end of such ten-day period any other Class A-2
      Certificateholder notifies such purchasing Class A-2 Certificateholder
      that such other Class A-2 Certificateholder wants to participate in such
      purchase, then such other Class A-2 Certificateholder may join with the
      purchasing Class A-2 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-2 Trust held by each such Class A-2
      Certificateholder and (ii) if prior to the end of such ten-day period any
      other Class A-2 Certificateholder fails to notify the purchasing Class A-2
      Certificateholder of such other Class A-2 Certificateholder's desire to
      participate in such

<Page>
                                                                              18


      a purchase, then such other Class A-2 Certificateholder shall lose its
      right to purchase the Applicable Certificates pursuant to this Section
      7.01(b); and

            (c) each Class B Certificateholder shall have the right (which shall
      not expire upon any purchase of the Applicable Certificates or the Class
      A-2 Certificates pursuant to paragraph (a) or (b) above) to purchase all,
      but not less than all, of the Applicable Certificates and the Class A-2
      Certificates upon ten days' prior written notice to the Trustee, the Class
      A-2 Trustee and each other Class B Certificateholder, PROVIDED that (i) if
      prior to the end of such ten-day period any other Class B
      Certificateholder notifies such purchasing Class B Certificateholder that
      such other Class B Certificateholder wants to participate in such
      purchase, then such other Class B Certificateholder may join with the
      purchasing Class B Certificateholder to purchase all, but not less than
      all, of the Applicable Certificates and the Class A-2 Certificates PRO
      RATA based on the fractional undivided interest in the Class B Trust held
      by each such Class B Certificateholder and (ii) if prior to the end of
      such ten-day period any other Class B Certificateholder fails to notify
      the purchasing Class B Certificateholder of such other Class B
      Certificateholder's desire to participate in such a purchase, then such
      other Class B Certificateholder shall lose its right to purchase the
      Applicable Certificates and the Class A-2 Certificates pursuant to this
      Section 7.01(c); and

            (d) each Class C Certificateholder shall have the right (which shall
      not expire upon any purchase of the Applicable Certificates or the Class
      A-2 Certificates pursuant to paragraph (a), (b) or (c) above) to purchase
      all, but not less than all, of the Applicable Certificates, the Class A-2
      Certificates and the Class B Certificates upon ten days' prior written
      notice to the Trustee, the Class A-2 Trustee, the Class B Trustee and each
      other Class C Certificateholder, PROVIDED that (i) if prior to the end of
      such ten-day period any other Class C Certificateholder notifies such
      purchasing Class C Certificateholder that such other Class C
      Certificateholder wants to participate in such purchase, then such other
      Class C Certificateholder may join with the purchasing Class C
      Certificateholder to purchase all, but not less than all, of the
      Applicable Certificates, the Class A-2 Certificates and the Class B
      Certificates PRO RATA based on the fractional undivided interest in the
      Class C Trust held by each such Class C Certificateholder and (ii) if
      prior to the end of such ten-day period any other Class C
      Certificateholder fails to notify the purchasing Class C Certificateholder
      of such other Class C Certificateholder's desire to participate in such a
      purchase, then such other Class C Certificateholder shall lose its right
      to purchase the Applicable Certificates, the Class A-2 Certificates and
      the Class B Certificates pursuant to this Section 7.01(d); and

            (e) each Class D 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, the Class A-2 Certificates or the
      Class B Certificates pursuant to paragraph (a), (b), (c) or (d) above) to
      purchase all, but not less than all, of the Applicable Certificates, the
      Class A-2 Certificates, the Class B Certificates and the Class C
      Certificates upon ten days' prior written notice to the Trustee, the Class
      A-2 Trustee, the Class B Trustee, the Class C Trustee and each other Class
      D Certificateholder, PROVIDED that (i) if prior to the end of such ten-day
      period any other Class D Certificateholder (other than the Company or any
      of its Affiliates) notifies such purchasing Class D

<Page>
                                                                              19


      Certificateholder that such other Class D Certificateholder wants to
      participate in such purchase, then such other Class D Certificateholder
      may join with the purchasing Class D Certificateholder to purchase all,
      but not less than all, of the Applicable Certificates, the Class A-2
      Certificates, the Class B Certificates and the Class C Certificates PRO
      RATA based on the fractional undivided interest in the Class D Trust held
      by each such Class D Certificateholder and (ii) if prior to the end of
      such ten-day period any other Class D Certificateholder fails to notify
      the purchasing Class D Certificateholder of such other Class D
      Certificateholder's desire to participate in such a purchase, then such
      other Class D Certificateholder shall lose its right to purchase the
      Applicable Certificates, the Class A-2 Certificates, the Class B
      Certificates and the Class C Certificates pursuant to this Section
      7.01(e).

            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, but including any other amounts then due and payable to the Applicable
Certificateholders under this Agreement, the Intercreditor Agreement, the Escrow
Agreement or any Note Document or on or in respect of the Applicable
Certificates; PROVIDED, HOWEVER, that (i) if such purchase occurs after the
record date specified in Section 2.3(b) of the Escrow Agreement relating to the
distribution of unused Deposits and accrued and unpaid interest thereunder, such
purchase price shall be reduced by the aggregate amount of unused Deposits and
interest to be distributed under the Escrow Agreement (which deducted amounts
shall remain distributable to, and may be retained by, the Applicable
Certificateholder as of such record date) and (ii) if such purchase occurs after
a Record Date, such purchase price shall be reduced by the amount to be
distributed hereunder on the related Distribution Date (which deducted amounts
shall remain distributable to, and may be retained by, the Applicable
Certificateholder as of such Record Date); PROVIDED FURTHER 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 purchasing, pursuant to the terms of this Agreement and the
Other Agreements, the Applicable Certificates, the Class A-2 Certificates, the
Class B Certificates, and the Class C Certificates which are senior to the
securities held by such purchaser(s). Each payment of the purchase price of the
Applicable Certificates referred to in the first sentence of this paragraph
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 7.01. Each Applicable
Certificateholder agrees by its acceptance of its Applicable Certificate that it
will, subject to Section 3.04 of the Basic Agreement, upon payment from such
Class A-2 Certificateholder(s), Class B Certificateholder(s), Class C
Certificateholder(s) or Class D Certificateholder(s), as the case may be, of the
purchase price set forth in the first sentence of this paragraph, 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
this Agreement, the Escrow Agreement, the Deposit Agreement, the Intercreditor
Agreement, the Liquidity Facility, 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 this Agreement, the Escrow Agreement, the
Deposit Agreement, the Intercreditor Agreement, the Liquidity Facility, the Note

<Page>
                                                                              20


Documents and all such Applicable Certificates and Escrow Receipts. 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 7.01, the terms "Class A-2 Certificate",
"Class A-2 Certificateholder", "Class A-2 Trust", "Class A-2 Trust Agreement",
"Class A-2 Trustee", "Class B Certificate", "Class B Certificateholder", "Class
B Trust", "Class B Trustee", "Class C Certificate", "Class C Certificateholder",
"Class C Trust", "Class C Trustee", "Class D Certificate", "Class D
Certificateholder", "Class D Trust" and "Class D Trustee" shall have the
respective meanings assigned to such terms in the Intercreditor Agreement.

            (f) This Section 7.01 supersedes and replaces Section 6.01(b) of the
Basic Agreement.

                                  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.

            Section 8.02. GOVERNING LAW. THIS TRUST SUPPLEMENT AND THE SERIES
2001-1A-1 CERTIFICATES SHALL BE GOVERNED BY AND CONSTRUED IN ACCORDANCE WITH THE
LAW OF THE STATE OF NEW YORK.

            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.



<Page>
                                                                              21




            IN WITNESS WHEREOF, the Guarantor, 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.


                                    NORTHWEST AIRLINES, INC.


                                    By:   ____________________________________
                                          Name:
                                          Title:



                                    NORTHWEST AIRLINES CORPORATION,
                                      as Guarantor

                                    By:   ____________________________________
                                          Name:
                                          Title:



                                    STATE STREET BANK AND TRUST
                                    COMPANY OF CONNECTICUT, NATIONAL
                                    ASSOCIATION, as Trustee


                                    By:   ____________________________________
                                          Name:
                                          Title:


<Page>


                                    EXHIBIT A

                               FORM OF CERTIFICATE

            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.

            Any person acquiring this Certificate by its acceptance hereof or
its interest herein, will be deemed to represent and warrant to and for the
benefit of each Owner Participant and the Company that either (i) the assets of
an employee benefit plan subject to Title I of the Employee Retirement Income
Security Act of 1974, as amended ("ERISA"), of a plan subject to Section 4975 of
the Internal Revenue Code of 1986, as amended (the "CODE"), of entities which
may be deemed to hold such plans' assets, or of another employee benefit plan
not subject to ERISA or Section 4975 of the Code (such as a governmental, church
or non-U.S. plan) have not been used to purchase this Certificate or (ii) one or
more prohibited transaction statutory or administrative exemptions applies such
that the use of such plan assets to purchase and hold this Certificate will not
constitute a non-exempt prohibited transaction under ERISA or Section 4975 of
the Code or a violation under any federal, state or local law that is
substantially similar to the provisions of Title I of ERISA or Section 4975 of
the Code.

                 NORTHWEST AIRLINES 2001-1A-1 PASS THROUGH TRUST

                                  Pass Through
                          Certificate, Series 2001-1A-1

                           Issuance Date: June 1, 2001

                 Final Legal Distribution Date: October 1, 2023

      Evidencing A Fractional Undivided Interest In The Northwest Airlines
      2001-1A-1 Pass Through Trust, The Property Of Which Includes Certain
      Equipment Notes Each Secured By An Aircraft Leased To Or Owned By
      Northwest Airlines, Inc.

Certificate        $________ Fractional undivided interest representing 0.__%
No. _____          of the Trust per $1,000 of Reference Principal Amount

            THIS CERTIFIES THAT _______________, for value received, is the
registered owner of a Fractional Undivided Interest in the amount of $_______
(the "REFERENCE PRINCIPAL AMOUNT") in the Northwest Airlines 2001-1A-1 Pass
Through Trust (the "TRUST") created by State Street Bank and Trust Company of
Connecticut, National Association, as trustee (the "TRUSTEE"), pursuant to a
Pass Through Trust Agreement, dated as of June 3, 1999 (as amended or
supplemented, the "BASIC AGREEMENT"), by and among the Trustee, Northwest
Airlines

<Page>
                                                                               2


Corporation, a Delaware corporation (the "Guarantor"), and Northwest Airlines,
Inc., a Minnesota corporation (the "COMPANY"), as supplemented by Trust
Supplement No. 2001-1A-1 thereto, dated as of June 1, 2001 (collectively, the
"AGREEMENT"), by and among the Trustee, the Guarantor 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 "Pass Through Certificates, Series
2001-1A-1" (herein called the "CERTIFICATES"). This Certificate is issued under
and is subject to the terms, provisions and conditions of the Agreement and the
Intercreditor Agreement, to which Agreement the Certificateholder of this
Certificate by virtue of the acceptance hereof assents and by which such
Certificateholder is bound. 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 a security interest in the Aircraft leased to or
owned by the Company.

            Each of the Certificates represents a Fractional Undivided Interest
in the Trust and the Trust Property and has 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 each April 1 and October 1 (a "REGULAR DISTRIBUTION DATE"),
commencing October 1, 2001 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 the 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

<Page>

                                                                               3


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 an obligation of, or an obligation
guaranteed by, or an interest in, the Guarantor, the Company or the Trustee or
any affiliate thereof. The Certificates are limited in right or payment, all as
more specifically set forth herein 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, proceeds, 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
Guarantor or the Company and the rights of the Certificateholders under the
Agreement at any time by the Guarantor, 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, 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.

            The Certificates are issuable only as registered Certificates
without coupons in minimum denominations of $1,000 Fractional Undivided
Interests and integral multiples thereof. 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.

<Page>
                                                                               4


            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 or beneficial owner of a Certificate, 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.

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

            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.

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

                                    NORTHWEST AIRLINES 2001-1A-1
                                      PASS THROUGH TRUST

                                    By:   STATE STREET BANK AND TRUST
                                            COMPANY OF CONNECTICUT,
                                            NATIONAL ASSOCIATION, as Trustee

                                          By:   _____________________________
                                                Name:
                                                Title:



<Page>
                                                                               5





               FORM OF THE TRUSTEE'S CERTIFICATE OF AUTHENTICATION

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

STATE STREET BANK AND TRUST
  COMPANY OF CONNECTICUT,
  NATIONAL ASSOCIATION,
  as Trustee

By:   _____________________________
      Name:
      Title:



<Page>

                                    EXHIBIT B

                          DTC Letter of Representations


<Page>

                                    EXHIBIT C

                           REGULAR DISTRIBUTION DATES
                                       AND
                               SCHEDULED PAYMENTS


<Table>
<Caption>

Regular Distribution Date              Scheduled Payment
-------------------------              -----------------
<S>                                      <C>
April 1, 2003.....................       $10,112,983.20
October 1, 2003...................         6,331,821.02
April 1, 2004.....................         6,229,050.77
October 1, 2004...................         5,318,729.67
April 1, 2005.....................         6,309,498.41
October 1, 2005...................         5,480,824.30
April 1, 2006.....................         6,296,626.80
October 1, 2006...................         5,454,889.12
April 1, 2007.....................         6,289,686.23
October 1, 2007...................         5,459,038.79
April 1, 2008.....................         6,298,356.74
October 1, 2008...................         5,458,374.84
April 1, 2009.....................         6,298,409.48
October 1, 2009...................         5,458,481.07
April 1, 2010.....................         6,298,401.00
October 1, 2010...................         5,458,464.04
April 1, 2011.....................         2,051,686.93
October 1, 2011...................           506,545.68
April 1, 2012.....................         3,159,208.93
October 1, 2012...................           506,545.68
April 1, 2013.....................         3,840,760.93
October 1, 2013...................         5,312,591.65
April 1, 2014.....................         4,224,133.93
October 1, 2014...................           506,545.68
April 1, 2015.....................         2,453,335.29
October 1, 2015...................           506,545.68
April 1, 2016.....................         2,437,462.93
October 1, 2016...................           506,545.68
April 1, 2017.....................         1,442,065.60
October 1, 2017...................           506,545.68
April 1, 2018.....................         5,037,214.93
October 1, 2018...................           506,545.68
April 1, 2019.....................         5,037,214.93
October 1, 2019...................           506,545.68
April 1, 2020.....................         5,037,214.93
October 1, 2020...................           506,545.68
April 1, 2021.....................         5,037,214.93
October 1, 2021...................           506,545.68
April 1, 2022.....................        52,413,801.79
</Table>