<PAGE>
                                                                 Exhibit 4(b)(2)

                                                                  EXECUTION COPY

         This Trust Supplement No. 1999-3B, dated as of December 9, 1999 (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 or refinance the acquisition of
fourteen new British Aerospace Avro RJ85 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 Owned 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
"1999-3B TRUST" or the "APPLICABLE TRUST") for the benefit of the
Certificateholders, and the initial Certificateholders as the grantors of the
1999-3B Trust, by their respective acceptances of the Certificates, join in the
creation of this 1999-3B Trust with the Trustee;

         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

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                                                                               2


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
APass Through Certificates, Series 1999-3B" (hereinafter defined as the ASERIES
1999-3B CERTIFICATES" or the "APPLICABLE CERTIFICATES"). Each Series 1999-3B
Certificate represents a Fractional Undivided Interest in the 1999-3B Trust
created hereby.

         The terms and conditions applicable to the Series 1999-3B Certificates
are as follows:

                  (a) The aggregate principal amount of the Series 1999-3B
         Certificates that shall be authenticated under the Agreement (except
         for Series 1999-3B Certificates authenticated and delivered pursuant to
         Sections 3.03, 3.04 and 3.05 of the Basic Agreement) upon their initial
         issuance is $58,013,000.

                  (b) The Cut-off Date is July 31, 2000.

                  (c) The Regular Distribution Dates with respect to any payment
         of Scheduled Payments means each April 1 and October 1, commencing on
         April 1, 2000, 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 1999-3B Certificates shall be in the form
         attached hereto as Exhibit A. Each purchaser of Series 1999-3B
         Certificates, by its acceptance of such

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                                                                               3


         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 (AERISA"), or of a plan subject to Section 4975 of the Internal
         Revenue Code of 1986, as amended (the ACODE") or of entities which may
         be deemed to hold such plans, have not been used to purchase Series
         1999-3B 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.

                  (ii) The Series 1999-3B 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 ACLEARING 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 1999-3B 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:

           Registration Number         Aircraft Type           Engine Type
           -------------------         -------------           -----------

        N523XJ..................         Avro RJ85              LF507-1F

        N524XJ..................         Avro RJ85              LF507-1F

        N525XJ..................         Avro RJ85              LF507-1F

        N526XJ..................         Avro RJ85              LF507-1F

        N527XJ..................         Avro RJ85              LF507-1F

        N528 XJ.................         Avro RJ85              LF507-1F

        N529XJ..................         Avro RJ85              LF507-1F

        N530XJ..................         Avro RJ85              LF507-1F

        N531XJ..................         Avro RJ85              LF507-1F

        N532XJ..................         Avro RJ85              LF507-1F

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                                                                               4


           Registration Number         Aircraft Type           Engine Type
           -------------------         -------------           -----------

        N533XJ..................         Avro RJ85              LF507-1F

        N534XJ..................         Avro RJ85              LF507-1F

        N535XJ..................         Avro RJ85              LF507-1F

        N536XJ..................         Avro RJ85              LF507-1F

                  (i) At the Escrow Agent's request under the Escrow Agreement,
         the Trustee shall affix the corresponding Escrow Receipt to each Series
         1999-3B Certificate. In any event, any transfer or exchange of any
         Series 1999-3B 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 1999-3B Certificate shall be
         permitted unless the corresponding Escrow Receipt is attached thereto
         and also is so transferred or exchanged. By acceptance of any Series
         1999-3B Certificate to which an Escrow Receipt is attached, each
         Certificateholder of such a Series 1999-3B 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, DEPOSIT AGREEMENT AND ESCROW
AGREEMENT. The Series 1999-3B Certificates are subject to the Intercreditor
Agreement, the Deposit Agreement and the Escrow Agreement.

         Section 1.03. RANKING OF SERIES 1999-3B CERTIFICATES. The Series
1999-3B 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
1999-3B Certificates will be supported by a Liquidity Facility to be provided by
the Liquidity Provider for the benefit of the Certificateholders.

         Section 1.05. [Reserved]

         Section 1.06. RANKING OF EQUIPMENT NOTES. The Equipment Notes will be
subject to the ranking and priority as set forth in the related Indenture.

         Section 1.07. 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.

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                                                                               5
                                   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 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.

                                   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: Means the 14 new British Aerospace Avro RJ85 which
         were sold or are expected to be sold to the Owner Trustee or the
         Company during the period from April 1999 through May 2000.

                  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.

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                                                                               6


                  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
         December 9, 1999 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.

                  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.

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

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

                  ESCROW AGENT: Means initially, First Security 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 December 9, 1999 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
         Trustees, the Liquidity Providers named

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                                                                               7


         therein, the Policy Provider 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
         Trustees, State Street Bank and Trust Company, as Subordination Agent,
         the Escrow Agent and the Paying Agent.

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

                  OTHER AGREEMENTS: Means the Basic Agreement as supplemented by
         Trust Supplement No. 1999-3G (the A1999-3G TRUST SUPPLEMENT") dated the
         date hereof relating to Northwest Airlines 1999-3G Pass Through Trust
         and by Trust Supplement No. 1999-3C (the A1999-3C TRUST SUPPLEMENT")
         dated the date hereof relating to the Northwest Airlines 1999-3C Pass
         Through Trust.

                  OTHER TRUSTEES: Means the trustee under the Other Agreements,
         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.

                  POLICY: Has the meaning specified in the Intercreditor
         Agreement.

                  POLICY PROVIDER: Means, initially, MBIA Insurance Corporation,
         and any replacement or successor thereof appointed in accordance with
         the Policy Provider Agreement.

                  POLICY PROVIDER AGREEMENT: Has the meaning specified in the
         Intercreditor Agreement.

                  POLICY PROVIDER DEFAULT: Has the meaning specified in the
         Intercreditor Agreement.

<PAGE>
                                                                               8


                  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.

                  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.

                  PROSPECTUS SUPPLEMENT: Means the Prospectus Supplement dated
         December 2, 1999, relating to the offering of the Class G Certificates,
         the Class B Certificates and the Class C Certificates (each as defined
         in the Intercreditor Agreement).

                  RECORD DATE: Means the date 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.

                  SPECIAL PAYMENT: Means any payment (other than a Scheduled
         Payment) in respect of, or any proceeds of, any Equipment Note.

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

                  TRUST PROPERTY: Means (i) the Equipment Notes held as the
         property of the 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

<PAGE>
                                                                               9


         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
         Trust pursuant to the Intercreditor Agreement or the Liquidity
         Facility.

                  TRUSTS: Means, collectively, the Northwest Airlines 1999-3
         Pass Through Trusts to be formed pursuant to the Basic Agreement, as
         supplemented by this Trust Supplement and the Other Agreements.

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

                  UNDERWRITING AGREEMENT: Means the Underwriting Agreement dated
         as of December 2, 1999 by and among the Company, the Guarantor, Morgan
         Stanley & Co. Incorporated, Chase Securities Inc., Salomon Smith Barney
         Inc. and U.S. Bancorp Piper Jaffray Inc.

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


                                   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 (A) the withdrawal of one or more
Deposits on the Applicable Delivery Date in accordance with and to the extent
permitted by the terms of

<PAGE>
                                                                              10


the Escrow Agreement and the Deposit Agreement and (B) 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 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
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 or Deposits 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 of one or more Deposits 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 or Deposits 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.

         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 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.

<PAGE>
                                                                              11


         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 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 and the Note Documents to
         which it is a party;

                  (b) the execution, delivery and performance by the Trustee of
         this Trust Supplement, the Intercreditor Agreement, the Escrow
         Agreement and the Note Documents to which it is 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 and the Note Documents to which it is 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 and the Note Documents to which it is 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 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

<PAGE>
                                                                              12


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 purpose 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
         CERTIFICATEHOLDERS. Without the consent of the 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, any Liquidity Facility, the Policy or the
         Policy Provider Agreement, 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 the Policy Provider 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, any Liquidity
                  Facility, the Policy or the Policy Provider Agreement; 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, any Liquidity
                  Facility, the Policy or the Policy Provider Agreement 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 Agreements,
                  the Intercreditor Agreement, the Note Purchase Agreement, any
                  Liquidity Facility, the Policy or the Policy Provider
                  Agreement, 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,

<PAGE>
                                                                              13


                  the Intercreditor Agreement, the Note Purchase Agreement, any
                  Liquidity Facility, the Policy or the Policy Provider
                  Agreement; 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 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 Policy, the Policy Provider
                  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 Policy, the Policy Provider
                  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 Policy,
                  the Policy Provider 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 Policy,
                  the Policy Provider 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 eliminating any of the
         provisions of this Agreement, the Deposit Agreements, the Escrow
         Agreements, the Intercreditor Agreement, the Note Purchase Agreement,
         any Liquidity Facility, the Policy or the Policy Provider Agreement 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,

<PAGE>
                                                                              14


         the Intercreditor Agreement, the Note Purchase Agreement, any Liquidity
         Facility, the Policy or the Policy Provider Agreement; 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; or

                           (6) terminate the Policy or modify the Policy other
                  than amendments already contemplated or required by Section
                  3.06 of the Policy Provider Agreement and/or Section 2.6(c) or
                  3.7(c) of the Intercreditor Agreement.

                  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."

<PAGE>
                                                                              15


         (b) If Class D Certificates are issued, the Company, the Guarantor and
the Trustee, without the consent of the Applicable Certificateholders, may enter
into an agreement supplemental to this Trust Supplement whereby Class D
Certificateholders shall be granted purchase rights similar to those set forth
in Section 7.01 hereof.

         (c) 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.

                                   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: and

<PAGE>
                                       16


                  (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 (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;

                  (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) 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,

<PAGE>
                                                                              17


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-42 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.

         (d) Unless and until required otherwise by applicable authority, the
Trustee shall treat the Applicable Trust as a Agrantor 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 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 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. (a) At any time
after the occurrence and during the continuance of a Triggering Event, each
Applicable Certificateholder shall have the right to purchase, for the purchase
price set forth in Section 7.01 of the Other Agreement relating to the Class G
Certificates, all, but not less than all, of the Class G Certificates upon ten
days' written notice to the Class G Trustee and each other Applicable
Certificateholder, provided that (i) if prior to the end of such ten-day period
any other Applicable

<PAGE>
                                                                              18


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 G 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 a purchase, then
such other Applicable Certificateholder shall lose its right to purchase the
Class G Certificates pursuant to this Section 7.01(a).

         (b) By acceptance of its Applicable Certificate, each Applicable
Certificateholder agrees that at any time after the occurrence and during the
continuation of a Triggering Event, each Class C Certificateholder shall have
the right to purchase all, but not less than all, of the Class G Certificates
and the Applicable Certificates upon ten days' written notice to the Class G
Trustee, the Trustee and each other Class C Certificateholder, PROVIDED that (A)
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 Class G Certificates and the
Applicable Certificates pro rata based on the fractional undivided interest in
the Class C Trust held by each such Class C Certificateholder and (B) 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 pursuant to this Section 7.01(b).

         (c) Whether or not any Applicable Certificateholder or Class C
Certificateholder has exercised its rights pursuant to paragraph (a) or (b)
above, the Policy Provider (except in the event of a Policy Provider Default),
if it is then the Controlling Party, shall have the right to purchase all, but
not less than all, of the Class G Certificates upon ten days' written notice to
the Trustee and the holders of the Applicable Certificates.

         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

<PAGE>
                                                                              19


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 Class G Certificates and the Applicable 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 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 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 C
Certificateholder(s) 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 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.

         (d) As used in this Section 7.01, the terms "Class G
Certificateholder", "Class G Certificate", "Class G Trustee", "Class C
Certificateholder", "Class C Trust", "Class C Certificate" and "Class C Trustee"
shall have the respective meanings assigned to such terms in the Intercreditor
Agreement.

         (e) 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.

<PAGE>
                                                                              20


         Section 8.02. GOVERNING LAW. THIS TRUST SUPPLEMENT AND THE SERIES
1999-3G CERTIFICATES SHALL BE GOVERNED BY AND CONSTRUED IN ACCORDANCE WITH THE
LAWS 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>


         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 (ADTC"), 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"), or of a plan subject to Section 4975
of the Internal Revenue Code of 1986, as amended (the "CODE") or of entities
which may be deemed to hold such plans, 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.

                  NORTHWEST AIRLINES 1999-3B PASS THROUGH TRUST

                                  Pass Through
                           Certificate, Series 1999-3B

                         Issuance Date: December 9, 1999

                 Final Legal Distribution Date: October 1, 2016

         Evidencing A Fractional undivided interest In the Northwest Airlines
         1999-3B 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
No. _____           $________ Fractional undivided interest representing 0.__%
                    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 AREFERENCE PRINCIPAL AMOUNT") in the Northwest Airlines 1999-3B Pass
Through Trust (the ATRUST") created by State Street Bank and Trust Company of
Connecticut, National Association, as trustee (the ATRUSTEE"), pursuant to a
Pass Through Trust Agreement, dated as of June 3, 1999 (as amended or

<PAGE>
                                                                               2


supplemented, the ABASIC AGREEMENT"), by and among the Trustee, Northwest
Airlines Corporation, a Delaware corporation (the AGuarantor"), and Northwest
Airlines, Inc., a Minnesota corporation (the ACOMPANY"), as supplemented by
Trust Supplement No. 1999-3B thereto, dated as of December 9, 1999
(collectively, the AAGREEMENT"), 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 APass Through
Certificates, Series 1999-3B" (herein called the ACERTIFICATES"). 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 ATRUST
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 AREGULAR DISTRIBUTION DATE"),
commencing April 1, 2000 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

<PAGE>
                                                                               3


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 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 Certificate- holder 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

<PAGE>
                                                                               4


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 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 LAWS OF THE STATE OF NEW YORK WITHOUT GIVING EFFECT TO
THE CONFLICT OF LAWS PROVISIONS 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 1999-3B
                                 PASS THROUGH TRUST

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

                                       By:
                                           -------------------------------------
                                           Name:
                                           Title:

<PAGE>



              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


              Regular Distribution Date                   Scheduled Payment
              -------------------------                   -----------------

                  April 1, 2000 .................           $           0
                  October 1, 2000 ...............                  25,297
                  April 1, 2001 .................                       0
                  October 1, 2001 ...............               1,346,446
                  April 1, 2002 .................                       0
                  October 1, 2002 ...............               4,130,347
                  April 1, 2003 .................                       0
                  October 1, 2003 ...............               4,729,928
                  April 1, 2004 .................                       0
                  October 1, 2004 ...............               4,019,460
                  April 1, 2005 .................                       0
                  October 1, 2005 ...............               3,062,620
                  April 1, 2006 .................                       0
                  October 1, 2006 ...............               3,092,979
                  April 1, 2007 .................                       0
                  October 1, 2007 ...............               2,393,023
                  April 1, 2008 .................                       0
                  October 1, 2008 ...............               2,041,333
                  April 1, 2009 .................                       0
                  October 1, 2009 ...............               2,211,444
                  April 1, 2010 .................               2,286,960
                  October 1, 2010 ...............               1,190,988
                  April 1, 2011 .................               4,947,981
                  October 1, 2011 ...............               1,290,238
                  April 1, 2012 .................               7,061,669
                  October 1, 2012 ...............                 444,619
                  April 1, 2013 .................               5,004,836
                  October 1, 2013 ...............                 158,557
                  April 1, 2014 .................               2,374,855
                  October 1, 2014 ...............               6,033,714
                  April 1, 2015 .................                 165,805
                  October 1, 2015 ...............                       0
                  April 1, 2016 .................                       0
                  October 1, 2016 ...............                       0
                  April 1, 2017 .................                       0
                  October 1, 2017 ...............                       0
                  April 1, 2018 .................                       0
                  October 1, 2018 ...............                       0
                  April 1, 2019 .................                       0