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                                                                    EXHIBIT 4(b)

                                                   Dated as of February 13, 2004

                                    GUARANTEE

         Reference is made to (i) the Indenture, dated as of February 1, 2004
(the "Base Indenture"), between AMR Corporation, a Delaware corporation (the
"Company") and Wilmington Trust Company, a Delaware banking corporation, as
trustee (the "Trustee"), as supplemented by Supplemental Indenture No. 2004-1,
dated as of February 13, 2004 (the "Supplemental Indenture"), among the Company,
American Airlines, Inc., a Delaware corporation, as guarantor ("the Guarantor"),
and the Trustee (the Base Indenture as so supplemented by the Supplemental
Indenture, the "Indenture") and (ii) the Company's 4.5% Senior Convertible Notes
due 2024 (each, a "Security" and collectively, the "Securities") issued pursuant
to the Indenture. Capitalized terms used herein and not defined herein have the
meanings ascribed thereto in the Indenture.

         The Guarantor (which term includes any successor person under the
Indenture), subject in every respect to the terms and conditions set forth in
the Indenture, hereby unconditionally guarantees, on an unsecured basis (the
"Guarantee"), to each Holder of a Security authenticated and delivered by the
Trustee in accordance with the terms of the Indenture, and to the Trustee on
behalf of such Holder, (i) (x) the due and punctual payment of the principal of,
and interest on, such Security, when and as the same shall become due and
payable, whether at Stated Maturity, by acceleration, redemption or otherwise,
(y) the due and punctual payment of interest on the overdue principal and
interest, if any, on such Security, to the extent lawful, and (z) the faithful
performance of all other obligations of the Company to the Holders or the
Trustee under such Security and the Indenture, in each case as set forth in
Article IX of the Supplemental Indenture and (ii) in case of any extension of
time of payment or renewal of any Securities or any of such other obligations,
that the same will be promptly paid in full when due or performed in accordance
with the terms of the extension or renewal, whether at Stated Maturity, by
acceleration or otherwise.

         The Guarantor hereby agrees to pay any and all costs and expenses
incurred by the Trustee or the Holders in enforcing their respective rights
under the Guarantee.

         Any term or provision of the Guarantee or the Indenture
notwithstanding, the Guarantee shall not exceed the maximum amount that can be
guaranteed by the Guarantor without rendering the Guarantee voidable under
applicable law relating to fraudulent conveyance or fraudulent transfer or
similar laws affecting the rights of creditors generally.

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         The obligations of the undersigned to the Holders of the Securities and
to the Trustee pursuant to this Guarantee and in the Indenture are expressly set
forth in the Indenture and reference is hereby made to the Indenture for the
precise terms of the Guarantee and all of the other provisions of the Indenture
to which this Guarantee relates. In the event of the assumption by a successor
Person of the obligations of the Guarantor as provided in Section 9.8 of the
Supplemental Indenture, such successor Person shall succeed to and be
substituted for the Guarantor hereunder and under the Indenture and all such
obligations of the Guarantor under the Indenture and the Guarantee shall
terminate.

         No past, present or future director, officer, employee, agent, member,
manager, trustee or stockholder, as such, of the Company, the Guarantor or any
successor Person or any Affiliate of any thereof shall have any liability for
any obligations of the Company, the Guarantor or any successor Person or any
Affiliate of any thereof, either directly or through the Company, the Guarantor
or any successor Person or any Affiliate of any thereof, under the Securities,
the Indenture or this Guarantee or for any claim based on, in respect of or by
reason of such obligations or their creation, whether by virtue of any rule of
law, statute or constitutional provision or by the enforcement of any assessment
or by any legal or equitable proceeding or otherwise.

         This Guarantee shall not be valid or obligatory for any purpose until
the certificate of authentication on the Securities shall have been executed by
the Trustee under the Indenture by the manual signature of one of its authorized
signatories.

         This Guarantee shall be governed by and construed in accordance with
the law of the State of New York, including all matters of construction,
validity and performance.

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         IN WITNESS WHEREOF, the Guarantor has caused this instrument to be duly
executed.

                                          AMERICAN AIRLINES, INC.

                                          By: /s/ Beverly K. Goulet
                                              ----------------------------
                                              Name:  Beverly K. Goulet
                                              Title: Vice President, Corporate
                                                     Development and Treasurer