<PAGE>

                                                              Exhibit 4.1

                            NORTHWEST AIRLINES, INC.

                              OFFICERS' CERTIFICATE


         Neal S. Cohen, Senior Vice President and Treasurer, and Douglas M.
Steenland, Executive Vice President, General Counsel and Secretary, of Northwest
Airlines, Inc., a Minnesota corporation (the "Company"), pursuant to Sections
1.2, 2.1 and 3.1 of the Indenture dated as of March 1, 1997 (the "Original
Indenture") among the Company, Northwest Airlines Holdings Corporation (as
predecessor to Northwest Airlines Corporation, "Old NWA Corp."), as guarantor,
and State Street Bank and Trust Company, as trustee (the "Trustee"), as
supplemented by a Supplemental Indenture, dated as of November 20, 1998 among
the Company, as issuer, Northwest Airlines Corporation ("NWA Corp."), Old NWA
Corp. and the Trustee (the "First Supplemental Indenture") and by a Second
Supplemental Indenture dated as of February 25, 1999 (the "Second Supplemental
Indenture" and, together with the Original Indenture and the First Supplemental
Indenture, the "Indenture") among the Company, NWA Corp., as guarantor, Old NWA
Corp. and the Trustee, and with respect to the $125,000,000 aggregate principal
amount of 9 1/2% Senior Quarterly Interest Bonds Due 2039 (QUIBs) (the "Firm
Bonds") and up to an additional $18,750,000 aggregate principal amount of 9 1/2%
Senior Quarterly Interest Bonds Due 2039 (QUIBs) (the "Option Bonds"; together
with the Firm Bonds, the "Bonds") of the Company pursuant to an option
exercisable until September 17, 1999, both as fully and unconditionally
guaranteed by NWA Corp., established by or pursuant to resolutions of the
Pricing Committee (the "Pricing Committee") of the Boards of Directors of the
Company and NWA Corp. adopted on August 19, 1999, each hereby CERTIFIES as
follows:

             1. Examinations and Conditions Precedent.
                -------------------------------------

                    a. Each of the undersigned has read the provisions of the
             Indenture setting forth conditions precedent to the authentication
             of the Bonds and the definitions in the Indenture relating thereto.

                    b. Each of the undersigned has examined resolutions of the
             Board of Directors of the Company and NWA Corp. and of the Pricing
             Committee adopted prior to the date hereof relating to the
             authorization, issuance, authentication and delivery of the Bonds,
             certificates of officers of the Company and corporate records of
             the Company, agreements and other instruments and documents deemed
             necessary as a basis for the opinion hereinafter expressed.

                    c. In the opinion of each of the undersigned, such
             examination is sufficient to enable him to express an informed
             opinion as to whether or not the conditions precedent referred to
             above have been complied with.

                    d. Each of the undersigned is of the opinion that, upon
             giving the Trustee the instructions specified in the authentication
             and delivery order of the Company dated the date hereof and
             delivered pursuant to Section 3.3 of the Indenture, the conditions
             precedent referred to above will have been complied with.


<PAGE>

                                                                               2


             2. Terms of the Bonds.
                ------------------

             The terms and conditions of the Bonds were duly approved and
       authorized by the Pricing Committee on August 19, 1999, in accordance
       with, or pursuant to, resolutions adopted by the Board of Directors of
       the Company on April 23, 1999, and such terms and conditions are set
       forth in the resolutions of the Pricing Committee duly adopted on August
       19, 1999, a copy of which is attached hereto as Exhibit A.

             3. Form of the Bonds.
                -----------------

             Attached hereto as Exhibit B is a true and correct copy of a global
       Bond representing the Bonds.


                            [Signature page follows]


<PAGE>

                                                                               3


         IN WITNESS WHEREOF, we have hereunto signed our names on this 27th day
of August, 1999.



                                 /s/ Neal S. Cohen
                                 -----------------------------------------
                                 Name:   Neal S. Cohen
                                 Title:  Senior Vice President
                                           and Treasurer



                                 /s/ Douglas M. Steenland
                                 -----------------------------------------
                                 Name:   Douglas M. Steenland
                                 Title:  Executive Vice President, General
                                              Counsel and Secretary



<PAGE>




                                                               EXHIBIT A

                            NORTHWEST AIRLINES, INC.
                         NORTHWEST AIRLINES CORPORATION

                        Resolutions of Pricing Committee
                        --------------------------------

                                 August 19, 1999

         WHEREAS, resolutions of the Board of Directors of Northwest Airlines,
Inc. (the "Corporation") duly adopted on April 23, 1999 (the "Resolutions")
authorized and ratified, inter alia, the Authorized Officers (as defined
therein) (i) to file one or more Registration Statements (as defined therein) to
cover the issuance and sale of the Corporation's Securities (as defined therein)
as fully and unconditionally guaranteed (such guarantee, the "Guarantee") by
Northwest Airlines Corporation (the "Guarantor"), of which an aggregate
principal amount of $944,766,000 is currently available for issuance, (ii) to
cause such Registration Statements to become effective and to maintain the
effectiveness of such Registration Statements under the Securities Act of 1933,
as amended (the "Securities Act"), (iii) to take any and all action which any
such Authorized Officer may deem necessary or advisable in order to effect the
registration or qualification (or exemption therefrom) of the Securities for
issue, offer, sale or trade under the Blue Sky or securities laws of any of the
States of the United States of America or of any foreign country or
jurisdiction, (iv) to negotiate, execute and deliver on behalf of, and in the
name of, the Corporation an underwriting agreement relating to the issuance and
sale of such Securities, (v) to prepare, negotiate, execute and deliver, as
appropriate, all other agreements, certificates, instruments, documents,
directions and receipts in connection with the issuance and sale of such
Securities, as any such Authorized Officer deems necessary or appropriate to
carry out the purposes and intent of such resolutions, such that the execution
and delivery, as appropriate, of any document by an Authorized Officer shall be
conclusive evidence of approval thereof on behalf of and, in the name of, the
Corporation and (vi) to have the Corporation make such payments as such
Authorized Officers deem necessary or advisable to effect the intent of the
foregoing resolutions;

         WHEREAS, the terms not defined herein shall have the meanings assigned
to them in the Indenture dated as of March 1, 1997 (the "Original Indenture")
among the Corporation, Northwest Airlines Holdings Corporation (as predecessor
to Northwest Airlines Corporation, "Old NWA Corp."), as guarantor, and State
Street Bank and Trust Company, as trustee (the "Trustee"), as supplemented by a
Supplemental Indenture, dated as of November 20, 1998 among the Corporation, as
issuer, the Guarantor, Old NWA Corp. and the Trustee (the "First Supplemental
Indenture") and by a Second Supplemental Indenture dated as of February 25, 1999
(the "Second Supplemental Indenture" and, together with the Original Indenture
and the First Supplemental Indenture, the "Indenture") among the Corporation,
the Guarantor, Old NWA Corp. and the Trustee; and

         WHEREAS, this Pricing Committee has been created by the Resolutions to
establish the terms of the issuance and sale of one series of senior unsecured
debt securities of the Corporation in an aggregate principal amount of up to
$300,000,000, as fully and unconditionally guaranteed


<PAGE>

by the Guarantor, and to take other actions in connection therewith as specified
in the Resolutions;

         NOW, THEREFORE, BE IT RESOLVED, that pursuant to and in accordance with
the Resolutions, $125,000,000 of aggregate principal amount of senior unsecured
debt obligations of the Corporation, and up to an additional $18,750,000
aggregate principal amount of senior unsecured debt obligations of the
Corporation, pursuant to an option exercisable until September 17, 1999, shall
be issued with the following terms:

         (1) The title of the series of debt securities shall be the "9 1/2%
      Senior Quarterly Interest Bonds Due 2039 (QUIBs)" (referred to herein as
      the "Bonds").

         (2) The aggregate principal amount of the Bonds shall be limited to
      $143,750,000.

         (3) The Bonds shall be issued on August 27, 1999 and shall mature on
      August 15, 2039.

         (4) The Bonds shall bear interest at the rate of 9 1/2% per annum
      calculated on the basis of a 360-day year of twelve 30-day months;
      interest in respect of each of the Bonds shall accrue from August 27, 1999
      or from the most recent Interest Payment Date to which interest has been
      paid or duly provided for until the principal thereof is paid or made
      available for payment; the Interest Payment Dates shall be quarterly on
      February 15, May 15, August 15 and November 15 of each year, commencing
      November 15, 1999; and the Regular Record Date for interest payable on any
      Interest Payment Dates shall be the close of business on the first day of
      each February, May, August and November, as the case may be, next
      preceding such Interest Payment Date.

         (5) Payment of the principal of, premium, if any, and interest on each
      of the Bonds shall be payable at the office or agency of the Corporation
      to be maintained in the City of New York; provided, however, that payments
      of principal, premium or interest on the Bonds may be made, at the option
      of the Corporation or the Guarantor, as the case may be, by check mailed
      to the address of the person entitled thereto as of the Regular Record
      Date and as shown on the Register or by wire transfer to an account
      located in the United States designated by the Holder of such Bond.

         (6)(a) Except as described in clause 6(b) hereof, the Bonds are not
      redeemable until August 27, 2004. On and after August 27, 2004, the
      Corporation may redeem all or a part of the Bonds upon not less than 30
      nor more than 60 days' notice mailed to each Holder of Bonds to be
      redeemed at the Holder's address appearing in the Register at a price
      equal to 100% of the principal amount thereof plus accrued and unpaid
      interest, if any, to the applicable redemption date (subject to the rights
      of holders of record on the relevant record date to receive interest due
      on an interest payment date that is on or prior to the Redemption Date)
      (such price the "Redemption Price").

                  (b) The Bonds may be redeemed at the option of the Corporation
            in whole, but not in part, on a date to be fixed by the Corporation
            upon not less than 30 nor more than 60 days' notice mailed to each
            Holder of Bonds to be redeemed at the Holder's address



<PAGE>

            appearing in the Register, at the Redemption Price, if the
            Corporation determines that as a result of:

                         (i) any actual or proposed change in or amendment to
                  the laws (or any regulations or rulings promulgated
                  thereunder) of the United States or any change in the
                  application, official interpretation or enforcement of such
                  laws, regulations or rulings;

                         (ii) any action taken by a taxing authority, which
                  action is generally applied or is taken with respect to the
                  Corporation;

                         (iii) a decision rendered by a court of competent
                  jurisdiction in the United States, whether or not such
                  decision was rendered with respect to the Corporation; or

                         (iv) a technical advice memorandum or letter ruling or
                  other administrative pronouncement issued by the National
                  Office of the United States Internal Revenue Service, on
                  substantially the same facts as those pertaining to the
                  Corporation,

            which change, amendment, action, decision, memorandum, letter ruling
            or pronouncement becomes effective, is proposed to become effective,
            or is issued on or after August 27, 1999, there is a substantial
            likelihood that the Corporation will not be entitled to deduct
            currently for United States federal income tax purposes the full
            amount of interest accrued in respect of the Bonds. In order to
            exercise its right to redeem the Bonds for tax reasons, the
            Corporation must deliver to the Trustee an opinion of counsel
            reasonably satisfactory to the Trustee confirming that the
            conditions described above have been met.

                  (c) If less than all of the Bonds are to be redeemed, the
            Trustee shall select the Bonds to be redeemed by such method as the
            Trustee shall deem fair and appropriate. The Trustee may select for
            redemption Bonds and portions of Bonds in amounts of $25 or integral
            multiples of $25.

         (7) The Corporation shall have no sinking fund or analogous obligations
      in respect of the Bonds.

         (8) The Bonds shall be issued in denominations of $25 or any integral
      multiple of $25 in excess of $25.

         (9) Principal of, premium, if any, and interest on the Bonds shall be
      payable in Dollars.

         (10) The Corporation shall not elect to have payments of principal of,
      premium, if any, or interest on the Bonds made in a currency other than
      that in which the Bonds are denominated or designated to be payable; the
      Bonds may be satisfied and discharged only as provided in Article 4 of the
      Indenture.

<PAGE>


         (11) Amounts of payments of principal of, premium, if any, and interest
      shall not be payable on the Bonds with reference to an index, formula or
      other similar method.

         (12) Upon a declaration of acceleration of the Bonds, the principal of
      the Bonds may be declared due and payable in the manner and with the
      effect provided in the Indenture. Upon (i) payment of the amount of
      principal so declared due and payable, (ii) payment of interest on any
      overdue principal and overdue interest (in each case to the extent that
      the payment of such interest shall be legally enforceable) and (iii) the
      occurrence of certain other events as set forth in the Indenture, all of
      the Corporation's and the Guarantor's obligations in respect of the
      payment of the principal of and interest, if any, on the Bonds shall
      terminate.

         (13) Interest on any Bond shall be payable to the Person in whose name
      such Bond is registered at the close of business on the Regular Record
      Date for such interest, pursuant to Section 3.7 of the Indenture; interest
      payable on a temporary or permanent global Bond shall be paid only as
      provided in Section 2.3 and Section 3.4 of the Indenture, as applicable.

         (14) There are no special rights that may be granted to Holders upon
      the occurrence of particular events.

         (15) There are no deletions from, modifications of or additions to the
      Events of Default set forth in Section 5.1 of the Indenture or covenants
      of the Corporation and/or the Guarantor set forth in Article 9 of the
      Indenture.

         (16) The Bonds shall be issued as Registered Securities.

         (17) The global bonds representing the Bonds shall be dated the date of
      original issuance of the Bonds.

         (18) The Bonds are not subject to defeasance or covenant defeasance.

         (19) The Registrar and Paying Agent shall be initially State Street
      Bank and Trust Company.

         (20) No warrants shall be issued by the Corporation or the Guarantor in
      connection with, or for the purchase of, the Bonds.

         (21) Initially, there shall be no Exchange Rate Agent.

         (22) The Bonds shall be issued in fully registered form, without
      coupons, and represented, as to each such series, by one or more permanent
      global bonds; the initial depositary for the Bonds shall be The Depository
      Trust Company ("DTC"), and the Bonds shall be registered in the name of
      Cede & Co. as a nominee of DTC; and as provided in the Indenture and
      subject to certain limitations therein set forth, the Bonds are
      exchangeable for a like aggregate principal amount of Bonds of the same
      series of like tenor of a different authorized denomination, as requested
      by the Holder surrendering the same.

         (23) Bearer Securities in respect of the Bonds shall not be issued.


<PAGE>

         (24) Other terms of the Bonds are as follows:

                  (a) The price at which the Bonds shall be sold to the
         Underwriters (as defined below), pursuant to the Underwriting Agreement
         dated August 19, 1999 among Northwest, the Guarantor and Morgan Stanley
         & Co. Incorporated, as representative for the underwriters named on
         Schedule 1 therein (the "Underwriters"), shall be 96.85% of their
         aggregate principal amount; and

                  (b) As provided in the Indenture and subject to certain
         limitations set forth therein, the obligation of the Corporation to pay
         principal of, and interest on, the Bonds is unconditionally guaranteed
         on a senior unsecured basis pursuant to the Guarantee endorsed thereon
         by the Guarantor.

                  (c) The Bonds shall be signed on behalf of the Corporation by
         any Co-Chairman, President, Executive Vice President, Senior Vice
         President, Vice President, Treasurer or Assistant Treasurer of the
         Corporation and attested by its Secretary or any of its Assistant
         Secretaries, provided that the signature of any such officer may be,
         but need not be, a facsimile signature imprinted or otherwise
         reproduced on the Bonds, and for that purpose the Corporation has
         adopted as binding upon it the facsimile signature of any present or
         future Co-Chairman, President, Executive Vice President, Senior Vice
         President, Vice President, Treasurer or Assistant Treasurer, Secretary
         or Assistant Secretary of the Corporation, notwithstanding the fact
         that at the time the Bonds shall be authenticated or delivered or
         disposed of such individual shall have ceased to hold such position
         with the Corporation; and, in case any of the above-named officers of
         the Corporation whose facsimile signature shall appear on any of the
         Bonds shall cease to hold such office before the Bonds have been
         authenticated and delivered or disposed of by the Corporation, such
         Bonds nevertheless may be authenticated and delivered or disposed of
         and such Bonds shall be valid as though such person had not ceased to
         hold such position with the Corporation; and any such Bonds as shall
         have been so authenticated, delivered or disposed of have been adopted
         by the Corporation as its binding obligations.

                  (d) The Bonds shall be in substantially the form set forth in
         Exhibit A attached hereto, with such changes and modifications as the
         Authorized Officers executing the same shall approve, such approval to
         be conclusively evidenced by such execution, and the Trustee's
         Certificate of Authentication shall be as set forth in the Indenture.

                  (e) The terms and conditions of the Bonds not otherwise
         specified herein or in the form of each of the Bonds shall be as
         specified in the Indenture; provided, however, that, to the extent that
         any provision herein with respect to the Bonds is inconsistent with any
         provision in the Indenture, the provisions enumerated herein shall
         control; and provided further, however, that, notwithstanding the
         above, the terms of the Bonds enumerated herein are subject to, and
         qualified in their entirety by reference to, the Trust Indenture Act of
         1939, as amended;

         FURTHER RESOLVED, that pursuant to and in accordance with the
Resolutions, a specified aggregate principal amount of Bonds (including all the
Bonds) may be referred to as

<PAGE>


a specified number of Bonds, where each such Bond shall represent $25 of
indebtedness under the Indenture, limited, in the aggregate, to 5,750,000 Bonds.


<PAGE>

                                                                       EXHIBIT B

                                 [FORM OF] BOND

         UNLESS THIS CERTIFICATE IS PRESENTED BY AN AUTHORIZED REPRESENTATIVE OF
THE DEPOSITORY TRUST COMPANY, A NEW YORK CORPORATION ("DTC"), TO NORTHWEST
AIRLINES, INC. 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 AS THE REGISTERED
OWNER HEREOF, CEDE & CO., HAS AN INTEREST HEREIN.

         TRANSFERS OF THIS GLOBAL SECURITY SHALL BE LIMITED TO TRANSFERS IN
WHOLE, BUT NOT IN PART, BY DTC TO A NOMINEE OF DTC OR BY A NOMINEE THEREOF TO
DTC OR ANOTHER NOMINEE THEREOF OR BY DTC OR ANY SUCH NOMINEE TO A SUCCESSOR OF
DTC OR SUCH SUCCESSOR'S NOMINEE, UNLESS AND UNTIL THIS SECURITY IS EXCHANGED IN
WHOLE OR IN PART FOR SECURITIES IN DEFINITIVE FORM AND TRANSFERS IN PART OF THIS
GLOBAL SECURITY SHALL BE LIMITED TO TRANSFERS MADE IN ACCORDANCE WITH THE
RESTRICTIONS SET FORTH IN THE INDENTURE HEREINAFTER REFERRED TO.

Registered                                       Principal Amount:  $142,500,000
No. CR-2                                                   CUSIP No.:  667281208

                            NORTHWEST AIRLINES, INC.

              9 1/2% Senior Quarterly Interest Bond Due 2039 (QUIB)

                     GUARANTEED AS TO PAYMENT OF PRINCIPAL,
                        PREMIUM, IF ANY, AND INTEREST BY
                         NORTHWEST AIRLINES CORPORATION


         1. Principal and Interest. NORTHWEST AIRLINES, INC., a corporation duly
organized and existing under the laws of the State of Minnesota (herein called
the "Company", which term includes any successor corporation under the Indenture
hereinafter referred to), for value received, hereby promises to pay to CEDE &
CO., or registered assigns, the principal sum of ONE HUNDRED FORTY TWO MILLION
FIVE HUNDRED THOUSAND DOLLARS AND NO CENTS ($142,500,000) on August 15, 2039,
and to pay interest thereon from August 27, 1999 or from the most recent
Interest Payment Date to which interest has been paid or duly provided for,
quarterly on February 15, May 15, August 15 and November 15 (each an "Interest
Payment Date") in each year, commencing November 15, 1999 at the rate of 9 1/2%
per annum until the principal hereof is paid or made available for payment.
Interest will be computed on the basis of a 360 day year of twelve 30 day
months. The interest so payable, and punctually paid or



<PAGE>

duly provided for, on any Interest Payment Date will, as provided in such
Indenture, be paid to the Person in whose name this Security (or one or more
predecessor Securities) is registered at the close of business on the fifteenth
day preceding such interest payment date, which shall be the first day of
February, May, August and November (whether or not a Business Day), as the case
may be, next preceding such Interest Payment Date. Any such interest not so
punctually paid or duly provided for will forthwith cease to be payable to the
Holder on such Regular Record Date and may either be paid to the Person in whose
name this Security (or one or more Predecessor Securities) is registered at the
close of business on a Special Record Date for the payment of such Defaulted
Interest to be fixed by STATE STREET BANK AND TRUST COMPANY, notice whereof
shall be given to Holders of Securities of this series not less than 10 days
prior to such Special Record Date, or be paid on a specified date in any other
lawful manner not inconsistent with the requirements of any securities exchange
on which the Securities of this series may be listed, and upon such notice as
may be required by such exchange, all as more fully provided in said Indenture.

         2. Indenture. This Security is one of a duly authorized series of
securities of the Company (herein called the "Securities"), issued and to be
issued in one or more series under an indenture, dated as of March 1, 1997 (the
"Original Indenture") among the Company, Northwest Airlines Holdings Corporation
(as predecessor to Northwest Airlines Corporation, "Old NWA Corp."), as
guarantor, and State Street Bank and Trust Company, as trustee (the "Trustee"),
as supplemented by a Supplemental Indenture, dated as of November 20, 1998 among
the Company, as issuer, Northwest Airlines Corporation (as successor to
Northwest Airlines Holdings Corporation, "NWA Corp."), Old NWA Corp. and the
Trustee (the "First Supplemental Indenture") and by a Second Supplemental
Indenture dated as of February 25, 1999 (the "Second Supplemental Indenture"
and, together with the Original Indenture and the First Supplemental Indenture,
the "Indenture") among the Company, NWA Corp., as guarantor (the "Guarantor"),
Old NWA Corp. and the Trustee, and with respect to which, the terms of this
Security were established pursuant to the Officers' Certificate delivered
pursuant to Section 3.1 of the Indenture and dated the date hereof, to which
Indenture and all indentures supplemental thereto reference is hereby made for a
statement of the respective rights, limitations of rights, duties and immunities
thereunder of the Company, the Guarantor, the Trustee and the Holders of the
Securities and of the terms upon which the Securities are, and are to be,
authenticated and delivered.

         This Security is one of the series designated as the "9 1/2% Senior
Quarterly Interest Bonds Due 2039 (QUIBs)" of the Company, limited in aggregate
principal amount to $142,500,000. The Securities are unsecured obligations of
the Company and rank pari passu with all unsecured and unsubordinated
obligations of the Company.

         The terms of the Securities include those stated in the Indenture and
those made part of the Indenture by reference to the Trust Indenture Act of
1939, as amended (15 U.S.C. sections 777aaa-777bbbb) (the "TIA"), as in effect
on the date of the Indenture (except as otherwise indicated in the Indenture).
Notwithstanding anything to the contrary herein, the Securities are subject to
all such terms, and Holders of Securities are referred to the Indenture and the
TIA for a statement of them.

         3. Method of Payment. Payment of the principal of, premium, if any, and
interest on each of the Securities shall be payable at the office or agency of
the Company to be maintained in the City of New York; provided, however, that
payments of principal, premium or interest on



<PAGE>

the Securities may be made, at the option of the Company or the Guarantor, as
the case may be, by check mailed to the address of the person entitled thereto
as of the Regular Record Date and as shown on the Register or by wire transfer
to an account located in the United States designated by the Holder of such
Security. Principal of, premium, if any, and interest on the Securities shall be
payable in Dollars.

         4. Registrar and Paying Agent. The Registrar and Paying Agent shall be
initially STATE STREET BANK AND TRUST COMPANY.

         5. Optional Redemption. (a) Except as described in clause 5(b) hereof,
the Securities are not redeemable until August 15, 2004. On and after August 15,
2004, the Company may redeem all or a part of the Securities upon not less than
30 nor more than 60 days' notice mailed to each Holder of Securities to be
redeemed at the Holder's address appearing in the Register at a price equal to
100% of the principal amount thereof plus accrued and unpaid interest, if any,
to the applicable redemption date (subject to the rights of holders of record on
the relevant record date to receive interest due on an interest payment date
that is on or prior to the Redemption Date) (such price the "Redemption Price").

                  (b) The Securities may be redeemed at the option of the
Company in whole, but not in part, on a date to be fixed by the Company upon not
less than 30 nor more than 60 days' notice mailed to each Holder of Securities
to be redeemed at the Holder's address appearing in the Register, at the
Redemption Price, if the Company determines that as a result of:

                         (i) any actual or proposed change in or amendment to
                  the laws (or any regulations or rulings promulgated
                  thereunder) of the United States or any change in the
                  application, official interpretation or enforcement of such
                  laws, regulations or rulings;

                         (ii) any action taken by a taxing authority, which
                  action is generally applied or is taken with respect to the
                  Company;

                         (iii) a decision rendered by a court of competent
                  jurisdiction in the United States, whether or not such
                  decision was rendered with respect to the Company; or

                         (iv) a technical advice memorandum or letter ruling or
                  other administrative pronouncement issued by the National
                  Office of the United States Internal Revenue Service, on
                  substantially the same facts as those pertaining to the
                  Company,

which change, amendment, action, decision, memorandum, letter ruling or
pronouncement becomes effective, is proposed to become effective, or is issued
on or after August 27, 1999, there is a substantial likelihood that the Company
will not be entitled to deduct currently for United States federal income tax
purposes the full amount of interest accrued in respect of the Securities. In
order to exercise its right to redeem the Securities for tax reasons, the
Company must deliver to the Trustee an opinion of counsel reasonably
satisfactory to the Trustee confirming that the conditions described above have
been met.

         (c) If less than all of the Securities are to be redeemed, the Trustee
shall select the Securities to be redeemed by such method as the Trustee shall
deem fair and appropriate. The Trustee may


<PAGE>

select for redemption Securities and portions of Securities in amounts of $25 or
integral multiples of $25.

         6. Sinking Fund. The Company shall have no sinking fund or analogous
obligations in respect of the Securities.

         7. Discharge and Defeasance. The Securities are not subject to
defeasance or covenant defeasance.

         8. Denominations; Transfers; Exchange. The Securities are in fully
registered form, without coupons, in denominations of $25 or any integral
multiple of $25 in excess of $25. A specified aggregate principal amount of the
Securities (including all) may be referred to as a specified number of Bonds,
where each such Bond shall represent $25 of indebtedness under the Indenture,
limited, in the aggregate, to 5,700,000 Bonds. A Holder may register transfers
of or exchange securities in accordance with the Indenture. No service charge
shall be made for any such registration of transfer or exchange, but the Company
may require payment of a sum sufficient to cover any tax or other governmental
charge payable in connection therewith. Prior to due presentment of this
Security for registration of transfer, the Company, the Trustee and any agent of
the Company or the Trustee may treat the Person in whose name this Security is
registered as the owner hereof for all purposes, whether or not this Security be
overdue, and neither the Company, the Trustee nor any such agent shall be
affected by notice to the contrary.

         9. Events of Default; Remedies. The Events of Default are as set forth
in Section 5.1 of the Indenture. If an Event of Default with respect to
Securities of this series shall occur and be continuing, the principal of the
Securities of this series may be declared due and payable in the manner and with
the effect provided in the Indenture. Upon a declaration of acceleration of the
Securities, the principal of the Securities may be declared due and payable in
the manner, and with the effect, provided in the Indenture.

         10. Amendments and Waivers. The Indenture permits, with certain
exceptions as therein provided, that with the written consent of the Holders of
not less than a majority of the aggregate principal amount of the Outstanding
Securities of each series to be adversely affected thereby, the Company, the
Guarantor and the Trustee may enter into an indenture or indentures thereto to
add any provisions or to change or eliminate any provisions of the Indenture or
any other indenture supplemental thereto or to modify the rights of the Holders
of each such series. The Indenture also provides, with certain exceptions
therein provided, that the Holders of not less than a majority of the aggregate
principal amount of the Outstanding Securities of any series by notice to the
Trustee may waive on behalf of the Holders of all Securities of such series a
past Default or Event of Default with respect to that series and its
consequences. Any such consent or waiver by the Holder of this Security shall be
conclusive and binding upon such Holder and upon all future Holders of this
Security and of any Security issued upon the registration of transfer hereof or
in exchange herefor or in lieu hereof, whether or not notation of such consent
or waiver is made upon this Security.

         11. Obligations Absolute. No reference herein to the Indenture and no
provision of this Security or of the Indenture shall alter or impair the
obligation of the Company, which is
<PAGE>

absolute and unconditional, to pay the principal of (and premium, if any) and
interest (if any) on this Security at the times, place and rate, and in the coin
or currency, herein prescribed.

         12. Guarantee. As provided in the Indenture and subject to certain
limitations set forth therein, the obligation of the Company to pay principal
of, and interest on, this Security is fully and unconditionally guaranteed on a
senior basis pursuant to the Guarantee endorsed hereon (the "Guarantee") by
NORTHWEST AIRLINES CORPORATION, the Guarantor. The Indenture provides that the
Guarantor shall be released from the Guarantee and that the Holder hereof shall
have no further claim against the Guarantor upon compliance with certain
conditions.

         13. No Recourse Against Others. No recourse shall be had for the
payment of the principal of, or premium, if any, or interest on, this Security,
or for any claim based hereon or otherwise in respect hereof, or based on or in
respect of the Indenture, any indenture supplemental thereto or the Guarantee,
against any incorporator, stockholder, officer or director, as such, past,
present or future, of the Company, the Guarantor or of any successor corporation
of either, whether by virtue of any constitution, statute or rule of law, or by
the enforcement of any assessment or penalty or otherwise, all such liability
being, by the acceptance hereof and as part of the consideration for the issue
hereof, expressly waived and released.

         14. Defined Terms. All capitalized terms used in this Security which
are defined in the Indenture shall have the meanings assigned to them in the
Indenture.

         15. Governing Law. THE INDENTURE AND THE SECURITIES SHALL BE GOVERNED
BY AND CONSTRUED IN ACCORDANCE WITH THE LAWS OF THE STATE OF NEW YORK.

         16. Successors and Assigns. All covenants and agreements of the Company
in the Indenture and the Securities shall bind its successors and assigns. All
agreements of the Trustee in the Indenture shall bind its successor.

         17. Authentication. Unless the certificate of authentication hereon has
been executed by the Trustee or an Authenticating Agent, by manual signature,
this Security shall not be entitled to any benefit under the Indenture or be
valid or obligatory for any purpose.

         18. Abbreviations. Customary abbreviations may be used in the name of a
Holder or an assignee, such as TEN COM (=tenants in common), TEN ENT (=tenants
by the entireties), JT TEN (=joint tenants with rights of survivorship and not
as tenants in common), CUST (=custodian), and U/G/M/A (=Uniform Gift to Minors
Act).

         19. CUSIP Numbers. Pursuant to a recommendation promulgated by the
Committee on Uniform Security Identification Procedures, the Company has caused
CUSIP numbers to be printed on the Securities, and the Trustee may use CUSIP
numbers in notices as a convenience to Holders. No representation is made as to
the accuracy of such numbers either as printed on the Securities or as contained
in any notice and reliance may be placed only on the other identification
numbers placed thereon.
<PAGE>

         IN WITNESS WHEREOF, the Company has caused this Security to be duly
executed and its corporate seal to be hereunto affixed and attested.

                                           NORTHWEST AIRLINES, INC.


Dated: August 27, 1999                     By:
                                              ----------------------------
                                              Name:  Neal S. Cohen
                                              Title: Senior Vice President
                                                     and Treasurer

Attest:
       ----------------------------
       Name:  Michael L. Miller
       Title: Assistant Secretary

         The Guarantor has fully and unconditionally guaranteed, to the extent
set forth in the Indenture and subject to the provisions in the Indenture, the
due and punctual payment of each series of Securities issued thereunder. In case
of the failure of the Company punctually to make any such payment, the Guarantor
hereby agrees to cause such payment to be made punctually.

         The obligations of the Guarantor to the Holders and to the Trustee
pursuant to the Guarantee are expressly set forth in Article Thirteen of the
Indenture and reference is hereby made to the Indenture for the precise terms of
the Guarantee.

         IN WITNESS WHEREOF, the Guarantor has caused this instrument to be duly
executed and its corporate seal to be hereunto affixed and attested.

                                           NORTHWEST AIRLINES CORPORATION


Dated: August 27, 1999                     By:
                                              ----------------------------
                                              Name:  Neal S. Cohen
                                              Title: Senior Vice President
                                                     and Treasurer

Attest:
       ----------------------------
       Name:  Michael L. Miller
       Title: Assistant Secretary
<PAGE>

                     TRUSTEE'S CERTIFICATE OF AUTHENTICATION


         This is one of the 9 1/2% Senior Quarterly Interest Bonds Due 2039
(QUIBs) described in the within-mentioned Indenture.

                                            STATE STREET BANK AND TRUST COMPANY,
                                              as Trustee


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

Dated: August 27, 1999
<PAGE>

                            ************************

                                 TRANSFER NOTICE


         FOR VALUE RECEIVED, the undersigned hereby sell(s), assign(s) and
transfer(s) unto____________________________________

(Please insert Social Security, Taxpayer Identification No. or other identifying
number of Assignee)

________________________________________________________________________________
________________________________________________________________________________

(Please print or typewrite name and address including postal zip code of
Assignee)


________________________________________________________________________________
the within Security of NORTHWEST AIRLINES, INC. (the "Company") and NORTHWEST
AIRLINES CORPORATION and does hereby irrevocably constitute and appoint
_____________ attorney to transfer the said Security on the books of the
Company, with full power of substitution in the premises.

Dated:___________                                    ___________________________
                                                     (The signature must be
                                                     guaranteed by an eligible
                                                     institution member of the
                                                     medallion signature
                                                     guarantee program.)

[NOTICE: The signature of this assignment must correspond with the name as
written upon the face of the within investment in every particular, without
alteration or enlargement or any change whatever.]