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                                                                    EXHIBIT 10.4

                                Amendment No. 17

                    TO THE A319/A320/A321 PURCHASE AGREEMENT

                          dated as of October 31, 1997

                                     between

                                 AVSA, S.A.R.L.

                                       and

                             US AIRWAYS GROUP, INC.

This Amendment No. 17 (this "AMENDMENT") entered into as of August 24, 2006, by
and between AIRBUS S.A.S., a societe par actions simplifiee (legal successor to
AVSA, S.A.R.L.), organized and existing under the laws of the Republic of
France, having its registered office located at 1, Rond Point Maurice Bellonte,
31700 Blagnac, France (the "SELLER"), and US Airways Group, Inc. (the "BUYER"),
a corporation organized and existing under the laws of the State of Delaware,
United States of America, having its principal corporate office located at 4000
East Sky Harbor Boulevard, Phoenix, Arizona 85034, U.S.A.;

WITNESSETH:

WHEREAS, the Buyer and the Seller entered into an Airbus A319/A320/A321 Purchase
Agreement, dated as of October 31, 1997, relating to the sale by the Seller and
the purchase by the Buyer of certain Airbus A319, A320 and A321 model aircraft
(the "Aircraft"), which, together with all Exhibits, Appendices and Letter
Agreements attached thereto and as amended by Amendment No. 1 dated as of June
10, 1998, Amendment No. 2 dated as of January 19, 1999, Amendment No. 3 dated as
of March 31, 1999, Amendment No. 4 dated as of August 31, 1999, Amendment No. 5
dated as of October 29, 1999, Amendment No. 6 dated as of April 19, 2000,
Amendment No. 7 dated as of June 29, 2000, Amendment No. 8 dated as of November
27, 2000, Amendment No. 9 dated as of December 29, 2000, Amendment No. 10 dated
as of April 9, 2001, Amendment No. 11 dated as of July 17, 2002, Amendment No.
12 dated as of March 29, 2003, Amendment No. 13 dated as of August 30, 2004,
Amendment No. 14 dated as of December 22, 2004, Amendment No. 15 dated as of
January 17, 2005, and Amendment No. 16 dated as of September 26, 2005
("AMENDMENT NO. 16"), thereto is hereinafter called the "Agreement";

WHEREAS, on September 27, 2005 the Buyer and the parent company of America West
Airlines, Inc. ("AWE") merged into a single corporation under the name US
Airways Group, Inc. and the

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rights, duties and obligations of the Buyer under the Agreement became the
rights, duties and obligations of the parent company of AWE;

WHEREAS, at the time of the merger both the Buyer and AWE had A320 family
aircraft on firm order from Seller;

WHEREAS, the Seller agreed to allow the Buyer and AWE the ** ;

WHEREAS, the Buyer has requested, and the Seller has agreed, on the terms and
conditions set forth in this Amendment, to ** as set forth herein;

WHEREAS, on March 1, 2006, AVSA, S.A.R.L. was merged into AIRBUS S.A.S. and on
that date all the rights, duties and obligations of AVSA, S.A.R.L. under the
Agreement became the rights, duties and obligations of AIRBUS S.A.S.

NOW, THEREFORE, IT IS AGREED AS FOLLOWS:

Capitalized terms used herein and not otherwise defined in this Amendment will
have the meanings assigned to them in the Agreement. The terms "herein,"
"hereof," and "hereunder" and words of similar import refer to this Amendment.

1.   ORDER CANCELLATION AND SURVIVAL OF AGREEMENT

     The Buyer and the Seller agree that the Buyer ** , as such term is defined
     in Amendment No. 16.

     **   :

     (i)  ** .

     (ii) **.

     (iii) ** .

     (iv) ** .

     (v)  ** .

2.   PREDELIVERY PAYMENTS

     **   .

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3.   AMENDMENT 12: LETTER AGREEMENT NO. 1

     Paragraph 11.4 of Letter Agreement No. 1 of Amendment No. 12 to the
     Agreement, as it may have been amended since signature of such amendment,
     is hereby deleted and replaced with the following:

     QUOTE

     11.4 ** .

     UNQUOTE

4.   EFFECT OF AMENDMENT

4.1  Signature of Amendment 14 to the AWE Agreement will be a condition
     precedent to the effectiveness of this Amendment.

4.2  Upon effectiveness, the provisions of this Amendment will constitute a
     valid amendment to the Agreement and the Agreement will be deemed to be
     amended to the extent herein provided. This Amendment supersedes and
     replaces any previous understandings, commitments, or representations
     whatsoever, whether oral or written, related to the subject matter of this
     Amendment; and this Amendment supersedes and replaces the letter agreement
     dated September 27, 2005, among the Buyer, AWE and AVSA, S.A.R.L., (then a
     wholly owned subsidiary of the Seller whose assets and liabilities have as
     of March 1, 2006, been assumed by the Seller), relating, among other
     things, to the cancellation by the Buyer of certain Aircraft.

4.3  Both parties agree that this Amendment will constitute an integral,
     nonseverable part of the Agreement, and that this Amendment will be
     governed by the provisions of the Agreement, except that if the Agreement
     and this Amendment have specific provisions that are inconsistent, the
     specific provisions contained in this Amendment will govern.

5.   GOVERNING LAW

     THIS AMENDMENT AND THE AGREEMENTS CONTEMPLATED HEREBY WILL, PURSUANT TO
     SECTION 5-1401 OF THE NEW YORK GENERAL OBLIGATIONS LAW, BE GOVERNED BY AND
     CONSTRUED AND THE PERFORMANCE THEREOF WILL BE DETERMINED IN ACCORDANCE WITH
     THE LAWS OF THE STATE OF NEW YORK WITHOUT GIVING EFFECT TO ITS CONFLICTS OF
     LAWS PROVISION THAT WOULD RESULT IN THE APPLICATION OF THE LAW OF ANY OTHER
     JURISDICTION. EXCEPT TO THE EXTENT THAT THE BANKRUPTCY COURT IN THE CHAPTER
     11 CASE HAS JURISDICTION THEREOF, ANY DISPUTE ARISING HEREUNDER WILL BE
     REFERRED TO THE FEDERAL OR STATE COURTS LOCATED IN NEW YORK CITY, NEW YORK,
     AND EACH OF THE PARTIES HERETO IRREVOCABLY SUBMITS TO AND ACCEPTS SUCH
     JURISDICTION.

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     IT IS AGREED THAT THE UNITED NATIONS CONVENTION ON CONTRACTS FOR THE
     INTERNATIONAL SALE OF GOODS WILL NOT APPLY TO THIS AMENDMENT OR TO THE
     AGREEMENTS CONTEMPLATED HEREIN.

6.   CONFIDENTIALITY

     Notwithstanding the Confidentiality provisions of Clause 22.4 of the
     Agreement, the Seller and the Buyer (including their employees, agents and
     advisors) agree to keep the terms and conditions of this Amendment hereby
     strictly confidential, except as required by applicable law or pursuant to
     legal process.

7.   COUNTERPARTS

     This Amendment may be signed in any number of separate counterparts. Each
     counterpart, when signed and delivered (including counterparts delivered by
     facsimile transmission), will be an original, and the counterparts will
     together constitute one same instrument.

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IN WITNESS WHEREOF, these presents were entered into as of the day and year
first above written.

US AIRWAYS GROUP, INC.                  AIRBUS S.A.S


By: /s/ Tom Weir                        By: /s/ Alain Rochet
    ---------------------------------       ------------------------------------
Its: Vice President and Treasurer       Its: Vice President Contracts
                                             Negotiation

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