<PAGE>   1

                                  EXHIBIT 4.21


                             NOTE PURCHASE AGREEMENT

                            Dated as of May 17, 2001

                                      Among

                          AMERICA WEST AIRLINES, INC.,

                            WILMINGTON TRUST COMPANY,
                    as Pass Through Trustee under each of the
                          Pass Through Trust Agreements

                            WILMINGTON TRUST COMPANY,
                             as Subordination Agent

                            WILMINGTON TRUST COMPANY,
                                 as Escrow Agent

                                       and

                            WILMINGTON TRUST COMPANY,
                                 as Paying Agent
<PAGE>   2
                        INDEX TO NOTE PURCHASE AGREEMENT

<TABLE>
<CAPTION>
                                                                              Page
                                                                              ----
<S>                                                                        <C>
SECTION 1.  Financing of Aircraft ......................................       2

SECTION 2.  Conditions Precedent .......................................       8

SECTION 3.  Representations and Warranties .............................       8

SECTION 4.  Covenants ..................................................      11

SECTION 5.  Notices ....................................................      14

SECTION 6.  Expenses ...................................................      15

SECTION 7.  Further Assurances .........................................      15

SECTION 8.  Miscellaneous ..............................................      16

SECTION 9.  Governing Law ..............................................      16
</TABLE>



                                    Schedules

Schedule I                 Aircraft and Scheduled Delivery Months
Schedule II                Pass Through Trust Agreements
Schedule III               Deposit Agreements
Schedule IV                Escrow and Paying Agent Agreements
Schedule V                 Mandatory Document Terms
Schedule VI                Mandatory Economic Terms
Schedule VII               Aggregate Amortization Schedule


                                      Annex

Annex A                    Definitions


                                    Exhibits

Exhibit A-1                Form of Leased Aircraft Participation Agreement
Exhibit A-2                Form of Lease
Exhibit A-3                Form of Leased Aircraft Indenture
Exhibit A-4                Form of Aircraft Purchase Agreement Assignment
Exhibit A-5                Form of Leased Aircraft Trust Agreement
Exhibit B                  Form of Delivery Notice

                                       -i-


                                      S-16
<PAGE>   3
Exhibit C-1                Form of Owned Aircraft Participation Agreement
Exhibit C-2                Form of Owned Aircraft Indenture
Exhibit D                  Additional Subordination Provision for the
                           Re-Issuance of the Series D Equipment Notes

                                      -ii-
<PAGE>   4
                             NOTE PURCHASE AGREEMENT

         This NOTE PURCHASE AGREEMENT, dated as of May 17, 2001, among (i)
AMERICA WEST AIRLINES, INC., a Delaware corporation (the "Company"), (ii)
WILMINGTON TRUST COMPANY ("WTC"), a Delaware banking corporation, not in its
individual capacity except as otherwise expressly provided herein, but solely as
trustee (in such capacity together with its successors in such capacity, the
"Pass Through Trustee") under each of the three separate Pass Through Trust
Agreements (as defined below), (iii) WILMINGTON TRUST COMPANY, a Delaware
banking corporation, as subordination agent and trustee (in such capacity
together with its successors in such capacity, the "Subordination Agent") under
the Intercreditor Agreement (as defined below), (iv) WILMINGTON TRUST COMPANY, a
Delaware banking corporation, as Escrow Agent (in such capacity together with
its successors in such capacity, the "Escrow Agent"), under each of the Escrow
and Paying Agent Agreements (as defined below) and (v) WILMINGTON TRUST COMPANY,
a Delaware banking corporation, as Paying Agent (in such capacity together with
its successors in such capacity, the "Paying Agent") under each of the Escrow
and Paying Agent Agreements.

                              W I T N E S S E T H:

         WHEREAS, capitalized terms used but not defined herein shall have the
meanings ascribed to such terms in Annex A hereto;

         WHEREAS, the Company has obtained commitments from the Manufacturer
pursuant to the Aircraft Purchase Agreement for the delivery of the 14 aircraft
listed on Schedule I hereto (together with any aircraft substituted therefor in
accordance with the Aircraft Purchase Agreement prior to the delivery thereof,
the "Aircraft");

         WHEREAS, pursuant to each of the Pass Through Trust Agreements set
forth in Schedule II hereto, and concurrently with the execution and delivery of
this Agreement, separate grantor trusts (collectively, the "Pass Through Trusts"
and, individually, a "Pass Through Trust") have been created to facilitate
certain of the transactions contemplated hereby, including, without limitation,
the issuance and sale of pass through certificates pursuant thereto
(collectively, the "Certificates") to provide for a portion of the financing of
the Aircraft;

         WHEREAS, the Company has entered into the Purchase Agreement dated as
of May 10, 2001 (the "Purchase Agreement") with the several initial purchasers
(the "Initial Purchasers") named therein, which provides that the Company will
cause each Pass Through Trustee to issue and sell the Certificates to the
Initial Purchasers;

         WHEREAS, concurrently with the execution and delivery of this
Agreement, (i) the Escrow Agents and the Depositary entered into the Deposit
Agreements set forth in Schedule III hereto (the "Initial Deposit Agreements")
whereby the applicable Escrow Agent agreed to direct the Initial Purchasers to
make certain deposits referred to therein on the Issuance Date (the "Initial
Deposits") and to permit the applicable Pass Through Trustee to make additional
deposits from time to time thereafter (the Initial Deposits together with such
additional deposits are collectively referred to as the "Deposits") and (ii) the
Pass Through Trustees, the Initial Purchasers, the Paying Agents and the Escrow
Agents entered into the Escrow and Paying
<PAGE>   5
                                                                               2

Agent Agreements set forth in Schedule IV hereto (the "Escrow and Paying Agent
Agreements") whereby, among other things, (a) the Initial Purchasers agreed to
deliver an amount equal to the amount of the Initial Deposits to the Depositary
on behalf of the applicable Escrow Agent and (b) the applicable Escrow Agent,
upon the Depositary receiving such amount, has agreed to deliver escrow receipts
to be affixed to each Certificate;

         WHEREAS, prior to (or, in the case of the utilization of bridge
financing, after) the delivery of each Aircraft from the Manufacturer, the
Company will determine whether to enter into a leveraged lease transaction as
lessee with respect to such Aircraft (a "Leased Aircraft") or to purchase as
owner such Aircraft pursuant to a secured loan transaction (an "Owned Aircraft")
and will give to the Pass Through Trustee a Delivery Notice (as defined below)
specifying its election;

         WHEREAS, upon receipt of a Delivery Notice with respect to an Aircraft,
subject to the terms and conditions of this Agreement, the applicable Pass
Through Trustees will enter into the applicable Financing Agreements relating to
such Aircraft;

         WHEREAS, upon the delivery of each Aircraft, each Pass Through Trustee
will fund its purchase of Equipment Notes with the proceeds of one or more
Deposits withdrawn by the applicable Escrow Agent under the related Deposit
Agreement bearing the same interest rate as the Certificates issued by such Pass
Through Trust;

         WHEREAS, concurrently with the execution and delivery of this
Agreement, (i) Westdeutsche Landesbank Girozentrale, a bank organized under the
laws of the State of North Rhine-Westphalia, Germany, acting through its New
York branch (the "Liquidity Provider"), has entered into two revolving credit
agreements (each, a "Liquidity Facility"), one each for the benefit of the
Certificateholders of the Class G Trust and the Class C Trust, with the
Subordination Agent, as agent for the Pass Through Trustee on behalf of each
such Pass Through Trust and (ii) the Pass Through Trustee, the Liquidity
Provider, the Policy Provider (as defined below) and the Subordination Agent
have entered into the Intercreditor Agreement, dated as of the date hereof (the
"Intercreditor Agreement"); and

         WHEREAS, concurrently with the execution and delivery of this Agreement
Ambac Assurance Corporation (the "Policy Provider") has entered into the
Insurance and Indemnity Agreement (the "Policy Provider Agreement"), with the
Company and the Subordination Agent, as agent and trustee for the Pass Through
Trustee of the Class G Trust on behalf of the Class G Trust, and the Policy
Provider has issued the certificate guaranty insurance policy (the "Policy")
provided for therein for the benefit of the Class G Certificateholders.

         NOW, THEREFORE, in consideration of the foregoing premises and the
mutual agreements herein contained and other good and valuable consideration,
the receipt and adequacy of which are hereby acknowledged, the parties hereto
agree as follows:

         SECTION 1. Financing of Aircraft. (a) The Company confirms that it has
entered into the Aircraft Purchase Agreement with the Manufacturer pursuant to
which the Company has agreed to purchase, and the Manufacturer has agreed to
deliver, the Aircraft in the months specified in Schedule I hereto, all on and
subject to terms and conditions specified in the
<PAGE>   6
                                                                               3


Aircraft Purchase Agreement. The Company agrees to finance the Aircraft in the
manner provided herein, all on and subject to the terms and conditions hereof
and of the relevant Financing Agreements.

         (b) In furtherance of the foregoing, the Company agrees to give the
parties hereto, the Depositary, the Policy Provider and each of the Rating
Agencies not less than two Business Days' prior written notice in the form of
the notice set out in Exhibit B hereto (a "Delivery Notice") of the scheduled
delivery date (the "Scheduled Delivery Date") (or, in the case of a substitute
Delivery Notice under Section 1(e) or (f) hereof, one Business Day's prior
notice) in respect of each Aircraft under the Aircraft Purchase Agreement, or in
the case of the utilization of bridge financing as contemplated by Section 1(e)
hereof in respect of any Aircraft, one Business Day's prior notice of the date
of the financing of such Aircraft pursuant to the relevant Financing Agreements
(or in the case of the Aircraft bearing registration number N824AW, if the
scheduled date of the financing of such Aircraft hereunder (which shall be
deemed to be a "Scheduled Delivery Date" hereunder) coincides with the Issuance
Date, the Delivery Notice therefor may be delivered to the parties hereto on
such date), which notice shall:

         (i) specify whether the Company has elected to treat such Aircraft as a
      Leased Aircraft or an Owned Aircraft;

         (ii) specify the Scheduled Delivery Date of such Aircraft (which shall
      be a Business Day before the Cut-off Date and, except as provided in
      Section 1(f) hereof, the date (the "Funding Date") on which the financing
      therefor in the manner provided herein shall be consummated);

         (iii) instruct the applicable Pass Through Trustee to execute and
      deliver to the relevant Escrow Agent a withdrawal certificate in the form
      of Exhibit B to the Escrow Agent so as to provide a Notice of Purchase
      Withdrawal to the Depositary with respect to the Equipment Notes to be
      issued in connection with the financing of such Aircraft;

         (iv) instruct the applicable Pass Through Trustee to enter into the
      Participation Agreement included in the Financing Agreements with respect
      to such Aircraft in such form and at such a time on or before the Funding
      Date specified in such Delivery Notice and to perform its obligations
      thereunder;

         (v) specify the aggregate principal amount of each series of Equipment
      Notes to be issued, and purchased by the Pass Through Trustees, in
      connection with the financing of such Aircraft scheduled to be delivered
      on such Funding Date (which shall in all respects comply with the
      Mandatory Economic Terms); and

         (vi) if such Aircraft is to be a Leased Aircraft, certify that the
      related Owner Participant (A) is not an Affiliate of the Company and (B)
      based on the representations of such Owner Participant, is either (1) a
      Qualified Owner Participant or (2) any other person the obligations of
      which under the Owner Participant Agreements (as defined in the applicable
      Participation Agreement) are guaranteed by a Qualified Owner Participant.

         (c) Upon receipt of a Delivery Notice, the Pass Through Trustees shall,
and shall cause the Subordination Agent to, enter into and perform their
obligations under the Partic-
<PAGE>   7
                                                                               4


ipation Agreement and other instructions specified in such Delivery Notice,
provided that such Participation Agreement and the other Lease Financing
Agreements or Owner Financing Agreements to be entered into pursuant to such
Participation Agreement shall be in the forms thereof annexed hereto in all
material respects with such changes therein as shall have been requested by the
related Owner Participant (in the case of Lease Financing Agreements), agreed to
by the Company and, if modified in any material respect, as to which prior
written consent of the Policy Provider shall have been obtained and as to which
Rating Agency Confirmation shall have been obtained from each Rating Agency by
the Company (to be delivered by the Company to the applicable Pass Through
Trustee on or before the relevant Delivery Date, it being understood that if
Policy Provider consent and Rating Agency Confirmation shall have been received
with respect to any Financing Agreements and such Financing Agreements are
utilized for subsequent Aircraft (or Substitute Aircraft) without material
modifications, no additional Policy Provider consent or Rating Agency
Confirmation shall be required); provided, however, that the relevant Financing
Agreements as executed and delivered shall not vary the Mandatory Economic Terms
and shall contain the Mandatory Document Terms. Notwithstanding the foregoing,
an Indenture may be modified to the extent required pursuant to Section 4(a)(vi)
of this Agreement. The Company shall pay the reasonable costs and expenses of
the Rating Agencies in connection with obtaining any such Rating Agency
Confirmation. With respect to each Aircraft, the Company shall cause WTC (or
such other person that meets the eligibility requirements to act as mortgagee
under the Leased Aircraft Indenture or Owned Aircraft Indenture) shall execute
as Loan Trustee the Financing Agreements relating to such Aircraft to which such
Loan Trustee is intended to be a party, and the Company shall concurrently
therewith execute such Financing Agreements to which the Company is intended to
be a party and perform its respective obligations thereunder. Upon the request
of the Policy Provider or of either Rating Agency, the Company shall deliver or
cause to be delivered to such Rating Agency a true and complete copy of each
Financing Agreement relating to the financing of each Aircraft together with a
true and complete set of the closing documentation (including legal opinions)
delivered to the related Loan Trustee, Subordination Agent and Pass Through
Trustee under the related Participation Agreement.

         (d) If after giving any Delivery Notice, there shall be a delay in the
delivery of an Aircraft, or if on the Scheduled Delivery Date of an Aircraft the
financing thereof in the manner contemplated hereby shall not be consummated for
whatever reason, the Company shall give the parties hereto and the Policy
Provider prompt notice thereof. Concurrently with the giving of such notice of
postponement or subsequently, the Company shall give the parties hereto and the
Policy Provider a substitute Delivery Notice specifying the date to which such
delivery and related financing shall have been re-scheduled (which shall be a
Business Day before the Cut-off Date on which the Escrow Agents shall be
entitled to withdraw one or more Deposits under each of the applicable Deposit
Agreements to enable each applicable Pass Through Trustee to fund its purchase
of the related Equipment Notes). Upon receipt of any such notice of
postponement, each applicable Pass Through Trustee shall comply with its
obligations under Section 7.01 of each of the Pass Through Trust Agreements and
thereafter the financing of the relevant Aircraft shall take place on the
re-scheduled Delivery Date therefor (all on and subject to the terms and
conditions of the relevant Financing Agreements) unless further postponed as
provided herein.

         (e) Anything in this Section 1 to the contrary notwithstanding, the
Company shall have the right at any time on or before the Scheduled Delivery
Date of any Aircraft, and
<PAGE>   8
                                                                               5


subsequent to its giving a Delivery Notice therefor, to postpone the Scheduled
Delivery Date of such Aircraft so as to enable the Company to change its
election to treat such Aircraft as a Leased Aircraft or an Owned Aircraft by
written notice of such postponement to the other parties hereto. The Company
shall subsequently give the parties hereto a substitute Delivery Notice
complying with the provisions of Section 1(b) hereof and specifying the new
Funding Date for such postponed Aircraft (which shall be a Business Day
occurring before the Cut-off Date and on which the Escrow Agents shall be
entitled to withdraw Deposits under each of the applicable Deposit Agreements
sufficient to enable each applicable Pass Through Trustee to fund its purchase
of the related Equipment Notes). In addition, the Company shall have the further
right, anything in this Section 1 to the contrary notwithstanding, to accept
delivery of an Aircraft under the Aircraft Purchase Agreement on the Delivery
Date thereof by utilization of bridge financing of such Aircraft and promptly
thereafter give the parties hereto a Delivery Notice specifying a Funding Date
not later than 90 days after the Delivery Date of such Aircraft and no later
than the Cut-off Date and otherwise complying with the provisions of Section
1(b) hereof. All other terms and conditions of this Note Purchase Agreement
shall apply to the financing of any such Aircraft on the re-scheduled Funding
Date therefor except (i) the re-scheduled Funding Date shall be deemed the
Delivery Date of such Aircraft for all purposes of this Section 1, (ii) the
related Financing Agreements shall be amended to reflect the original delivery
of such Aircraft to the Company and (iii) the related Financing Agreements shall
be amended to reflect the seller of such Aircraft, and the recipient of payment
of the purchase price therefor, as the Company and (iv) in the case of a Leased
Aircraft, the Aircraft Purchase Agreement Assignment shall be modified to cover
only an assignment of the relevant warranties.

         (f) If the Scheduled Delivery Date for any Aircraft is delayed for any
reason (including the casualty loss thereof) more than 30 days beyond the last
day of the month set forth opposite such Aircraft under the heading "Scheduled
Delivery Months" in Schedule I hereto, the Company may identify for delivery a
substitute aircraft therefor meeting the following conditions (a "Substitute
Aircraft"): (i) a Substitute Aircraft must be an Airbus A319-100 or A320-200
aircraft manufactured after the date of this Agreement, (ii) one or more
Substitute Aircraft of the same or different types may be substituted for one or
more Aircraft of the same or different types so long as after giving effect
thereto such substitution does not vary the Mandatory Economic Terms and (iii)
the Company shall be obligated to obtain prior written consent of the Policy
Provider and to obtain Rating Agency Confirmation in respect of the replacement
of any Aircraft by Substitute Aircraft. Upon the satisfaction of the conditions
set forth above with respect to a Substitute Aircraft, the Aircraft to be
replaced shall cease to be subject to this Agreement and all rights and
obligations of the parties hereto concerning such Aircraft shall cease, and such
Substitute Aircraft shall become and thereafter be subject to the terms and
conditions of this Agreement to the same extent as such Aircraft.

         (g) The Company shall have no liability for the failure of the Pass
Through Trustees to purchase Equipment Notes with respect to any Aircraft or
Substitute Aircraft, other than the Company's obligation, if any, to pay the
Deposit Make-Whole Premium and Deposit Break Amount pursuant to Section 4(a)(i)
of this Agreement.

         (h) The parties agree that if, in connection with the delivery of an
Aircraft or Substitute Aircraft, any Owner Participant who is to be a party to
any Lease Financing Agreement shall not be a "Citizen of the United States"
within the meaning of Section
<PAGE>   9
                                                                               6


40102(a)(15) of the Act, then the applicable Lease Financing Agreements shall be
modified, consistent with the Mandatory Document Terms, (x) to require such
Owner Participant to enter into a voting trust, voting powers or similar
arrangement satisfactory to the Company that (A) enables such Aircraft or
Substitute Aircraft to be registered in the United States and (B) complies with
the FAA regulations issued under the Act applicable thereto and (y) to be
otherwise consistent with such state of affairs.

         (i) Anything herein to the contrary notwithstanding, the Company shall
not have the right, and shall not be entitled, at any time to request the
issuance of Equipment Notes of any series to any Pass Through Trustee in an
aggregate principal amount in excess of the amount of the Deposits then
available for withdrawal by the Escrow Agent under and in accordance with the
provisions of the related Deposit Agreement.

         (j) Notwithstanding the foregoing provisions of this Section 1, and
anything herein to the contrary notwithstanding, upon not less than 30 days'
prior written notice to the parties hereto, the Company shall have the right,
within 120 days after the date any Aircraft has been financed as an Owned
Aircraft, to sell such Owned Aircraft and transfer title to such Owned Aircraft
to an Owner Trustee for the benefit of an Owner Participant (which shall be a
Qualified Owner Participant) in a transaction in which such Owner Trustee
assumes all of the obligations of the Company under the relevant Equipment Notes
and the Owned Aircraft Indenture on a non-recourse basis (with the Company being
released from such obligations, except to the extent accrued prior thereto),
leases the Aircraft to the Company and assigns such lease to the Loan Trustee
pursuant to an amended and restated trust indenture (a "Sale/Leaseback
Transaction"). In connection with such Sale/Leaseback Transaction, the Company
and the relevant Note Holders will execute and deliver appropriate documentation
permitting the Owner Trustee to assume the obligations of the Company under the
relevant Equipment Notes and the Owned Aircraft Indenture on a non-recourse
basis, releasing the Company from all obligations in respect of such Equipment
Notes and the Owned Aircraft Indenture (except to the extent accrued prior
thereto), and take all other actions as are reasonably necessary to permit such
assumption by the Owner Trustee. In connection with any such Sale/Leaseback
Transaction, the parties hereto agree that (a) the documents to be utilized
shall be (i) an amended and restated participation agreement amending and
restating the Participation Agreement, such amended and restated participation
agreement to be substantially in the form of the Leased Aircraft Participation
Agreement, among the Company, the relevant Note Holders, the Owner Participant,
the Owner Trustee, and the Loan Trustee, with (x)
<PAGE>   10
                                                                               7


such changes to such form to reflect the assumption of such Equipment Notes by
the Owner Trustee on a non-recourse basis rather than the issuance thereof by
the Owner Trustee and original purchase thereof by the Note Holders and also to
reflect the release of the Company from all obligations under such Equipment
Notes and the Owned Aircraft Indenture (except to the extent accrued prior
thereto) and (y) such other changes as may be permitted in accordance with the
provisions of Section 1(c) hereof applicable to a Leased Aircraft Participation
Agreement in connection with a leverage lease transaction, (ii) a lease
agreement, such lease agreement to be substantially in the form of the Lease
between the Company and the Owner Trustee with such changes as may be permitted
in accordance with the provisions of Section 1(c) hereof applicable to the Lease
in connection with a leveraged lease transaction, (iii) an amended and restated
trust indenture amending and restating the relevant Owned Aircraft Indenture,
such amended and restated trust indenture to be substantially in the form of a
Leased Aircraft Indenture, between the Owner Trustee and the Loan Trustee, with
(x) such changes to such form to reflect the assumption of all of the
obligations of the Owner Trustee under relevant Equipment Notes and the relevant
Owned Aircraft Indenture on a non-recourse basis and the release of the
obligations of the Company under such Equipment Notes and the relevant Owned
Aircraft Indenture and (y) such other changes as may be permitted in accordance
with the provisions of Section 1(c) hereof applicable to a Leased Aircraft
Indenture in connection with a leveraged lease transaction, (iv) a purchase
agreement assignment, such purchase agreement assignment to be substantially in
the form of the Aircraft Purchase Agreement Assignment between the Company and
the Owner Trustee with such changes as may be permitted in accordance with the
provisions of Section 1(c) hereof applicable to an Aircraft Purchase Agreement
Assignment in connection with a leveraged lease transaction, and (v) a trust
agreement, such trust agreement to be substantially in the form of a Trust
Agreement, between the Owner Trustee and the Owner Participant with such changes
as may be permitted in accordance with the provisions of Section 1(c) hereof
applicable to a Trust Agreement in connection with a leveraged lease transaction
and (b) the relevant Equipment Notes shall be delivered to the Loan Trustee for
cancellation in exchange for new equipment notes to be issued to the Note
Holders by the Owner Trustee upon the authentication thereof by the Loan
Trustee, such new equipment notes to be substantially in the form contained in
Section 2.01 of the Leased Aircraft Indenture. Such new equipment notes will
have the same payment terms except that in the event that the Company enters
into a Sale/Leaseback Transaction prior to the Delivery Period Termination Date,
the Company shall have the right to reoptimize the new equipment notes to be
issued to the Note Holders by the Owner Trustee in compliance with the Mandatory
Economic Terms and subject to obtaining Rating Agency Confirmation with respect
thereto.

         Notwithstanding the foregoing, the Company shall not have the right to
enter into a Sale/Leaseback Transaction unless the Company (i) causes to be
delivered to the Loan Trustee an opinion of counsel (both counsel and opinion
satisfactory to the Loan Trustee) to the effect that the Pass Through Trusts
will not be subject to Federal income tax as a result of such Sale/Leaseback
Transaction and (ii) furnishes to the Loan Trustee either (A) an opinion of
counsel to the effect that the Certificateholders will not recognize income,
gain or loss for Federal income tax purposes as a result of such Sale/Leaseback
Transaction and will be subject to Federal income tax on the same amount, in the
same manner and at the same time as would have been the case if such
Sale/Leaseback Transaction had not occurred or (B) furnishes to the Loan Trustee
both an opinion of counsel (both counsel and opinion satisfactory to the Loan
Trustee) that the Certificateholders should not recognize gain or loss for
Federal income tax purposes in connection with such Sale/Leaseback Transaction
and will be subject to Federal income tax on the same amount and in the same
manner and at the same time as would have been the case if such Sale/Leaseback
Transaction had not occurred and an indemnification in favor of the holders of
the Certificates in form and substance reasonably satisfactory to the Loan
Trustee and (ii) obtains Policy Provider consent and a Rating Agency
Confirmation with respect thereto. In addition, the Company agrees to otherwise
comply with the provisions of Sections 1(c) and 2 hereof in connection with any
Sale/Leaseback Transaction.
<PAGE>   11
                                                                               8


         SECTION 2. Conditions Precedent. The obligation of the Pass Through
Trustees to enter into, and to cause the Subordination Agent to enter into, any
Participation Agreement as directed pursuant to a Delivery Notice and to perform
its obligations thereunder is subject to satisfaction of the following
conditions:

         (a) no Triggering Event shall have occurred;

         (b) the Company shall have delivered a certificate to each such Pass
      Through Trustee, the Policy Provider and each Liquidity Provider stating
      that (i) such Participation Agreement and the other Financing Agreements
      to be entered into pursuant to such Participation Agreement do not vary
      the Mandatory Economic Terms and contain the Mandatory Document Terms,
      (ii) any substantive modification of such Financing Agreements from the
      forms of Financing Agreements attached to this Agreement do not materially
      and adversely affect the Policy Provider or the Certificateholders, and
      such certification shall be true and correct; and

         (c) a copy of the Rating Agency Confirmations and the Policy Provider
      consent required under Section 1(c) or 1(j) shall have been delivered to
      each such Pass Through Trustee.

         Anything herein to the contrary notwithstanding, the obligation of each
Pass Through Trustee to purchase Equipment Notes shall terminate on the Cut-off
Date.

         SECTION 3. Representations and Warranties. (a) The Company represents
and warrants that:

         (i) the Company is duly incorporated, validly existing and in good
      standing under the laws of the State of Delaware and is a "citizen of the
      United States" as defined in Section 40102 of the Act, and has the full
      corporate power, authority and legal right under the laws of the State of
      Delaware to execute and deliver this Agreement and each Financing
      Agreement to which it will be a party and to carry out the obligations of
      the Company under this Agreement and each Financing Agreement to which it
      will be a party;

         (ii) the execution and delivery by the Company of this Agreement and
      the performance by the Company of its obligations under this Agreement
      have been duly authorized by the Company and will not violate its
      Certificate of Incorporation or by-laws or (other than any violation that
      would not result in a Material Adverse Change to the Company) the
      provisions of any indenture, mortgage, contract or other agreement to
      which it is a party or by which it is bound; and

         (iii) assuming the due authorization, execution and delivery hereof by
      the other parties hereto this Agreement constitutes the legal, valid and
      binding obligation of the Company, enforceable against it in accordance
      with its terms, except as the same may be limited by applicable
      bankruptcy, insolvency, reorganization, moratorium or similar laws
      affecting the rights of creditors generally and by general principles of
      equity, whether considered in a proceeding at law or in equity.
<PAGE>   12
                                                                               9

         (b) WTC represents and warrants that:

         (i) WTC is duly incorporated, validly existing and in good standing
      under the laws of the State of Delaware and is a "citizen of the United
      States" as defined in Section 40102 of the Act, and has the full corporate
      power, authority and legal right under the laws of the State of Delaware
      and the United States pertaining to its banking, trust and fiduciary
      powers to execute and deliver this Agreement and each Financing Agreement
      to which it will be a party and to carry out the obligations of WTC, in
      its capacity as Subordination Agent, Pass Through Trustee or Paying Agent,
      as the case may be, under this Agreement and each Financing Agreement to
      which it will be a party;

         (ii) the execution and delivery by WTC, in its capacity as
      Subordination Agent, Pass Through Trustee or Paying Agent, as the case may
      be, of this Agreement and the performance by WTC, in its capacity as
      Subordination Agent, Pass Through Trustee or Paying Agent, as the case may
      be, of its obligations under this Agreement have been duly authorized by
      WTC, in its capacity as Subordination Agent, Pass Through Trustee or
      Paying Agent, as the case may be, and will not violate its articles of
      association or by-laws or the provisions of any indenture, mortgage,
      contract or other agreement to which it is a party or by which it is
      bound; and

         (iii) this Agreement constitutes the legal, valid and binding
      obligations of WTC, in its capacity as Subordination Agent, Pass Through
      Trustee or Paying Agent, as the case may be, enforceable against it in
      accordance with its terms, except as the same may be limited by applicable
      bankruptcy, insolvency, reorganization, moratorium or similar laws
      affecting the rights of creditors generally and by general principles of
      equity, whether considered in a proceeding at law or in equity.

         (c) The Pass Through Trustee hereby confirms to each of the other
parties hereto that its representations and warranties set forth in Section 7.15
of each Pass Through Trust Agreement are true and correct as of the date hereof.

         (d) The Subordination Agent represents and warrants that:

         (i) the Subordination Agent is duly incorporated, validly existing and
      in good standing under the laws of the State of Delaware, and has the full
      corporate power, authority and legal right under the laws of the State of
      Delaware and the United States pertaining to its banking, trust and
      fiduciary powers to execute and deliver this Agreement and each Financing
      Agreement to which it is or will be a party and to perform its obligations
      under this Agreement and each Financing Agreement to which it is or will
      be a party;

         (ii) this Agreement has been duly authorized, executed and delivered by
      the Subordination Agent; this Agreement constitutes the legal, valid and
      binding obligations of the Subordination Agent enforceable against it in
      accordance with its terms, except as the same may be limited by applicable
      bankruptcy, insolvency, reorganization, moratorium or similar laws
      affecting the rights of creditors generally and by general principles of
      equity, whether considered in a proceeding at law or in equity;
<PAGE>   13
                                                                              10


         (iii) none of the execution, delivery and performance by the
      Subordination Agent of this Agreement contravenes any law, rule or
      regulation of the State of Delaware or any United States governmental
      authority or agency regulating the Subordination Agent's banking, trust or
      fiduciary powers or any judgment or order applicable to or binding on the
      Subordination Agent and do not contravene the Subordination Agent's
      articles of association or by-laws or result in any breach of, or
      constitute a default under, any agreement or instrument to which the
      Subordination Agent is a party or by which it or any of its properties may
      be bound;

         (iv) neither the execution and delivery by the Subordination Agent of
      this Agreement nor the consummation by the Subordination Agent of any of
      the transactions contemplated hereby requires the consent or approval of,
      the giving of notice to, the registration with, or the taking of any other
      action with respect to, any Delaware governmental authority or agency or
      any federal governmental authority or agency regulating the Subordination
      Agent's banking, trust or fiduciary powers;

         (v) there are no Taxes payable by the Subordination Agent imposed by
      the State of Delaware or any political subdivision or taxing authority
      thereof in connection with the execution, delivery and performance by the
      Subordination Agent of this Agreement (other than franchise or other taxes
      based on or measured by any fees or compensation received by the
      Subordination Agent for services rendered in connection with the
      transactions contemplated by the Intercreditor Agreement or any of the
      Liquidity Facilities), and there are no Taxes payable by the Subordination
      Agent imposed by the State of Delaware or any political subdivision
      thereof in connection with the acquisition, possession or ownership by the
      Subordination Agent of any of the Equipment Notes (other than franchise or
      other taxes based on or measured by any fees or compensation received by
      the Subordination Agent for services rendered in connection with the
      transactions contemplated by the Intercreditor Agreement or any of the
      Liquidity Facilities); and

         (vi) there are no pending or threatened actions or proceedings against
      the Subordination Agent before any court or administrative agency which
      individually or in the aggregate, if determined adversely to it, would
      materially adversely affect the ability of the Subordination Agent to
      perform its obligations under this Agreement.

         (e) The Escrow Agent represents and warrants that:

         (i) the Escrow Agent is duly incorporated, validly existing and in good
      standing under the laws of the State of Delaware and has the full
      corporate power, authority and legal right under the laws of the State of
      Delaware pertaining to its banking, trust and fiduciary powers to execute
      and deliver this Agreement, each Deposit Agreement and each Escrow and
      Paying Agent Agreement (collectively, the "Escrow Agent Agreements") and
      to carry out the obligations of the Escrow Agent under each of the Escrow
      Agent Agreements;

         (ii) the execution and delivery by the Escrow Agent of each of the
      Escrow Agent Agreements and the performance by the Escrow Agent of its
      obligations hereunder
<PAGE>   14
                                                                              11


      and thereunder have been duly authorized by the Escrow Agent and will
      not violate its articles of association or by-laws or the provisions of
      any indenture, mortgage, contract or other agreement to which it is a
      party or by which it is bound; and

         (iii) each of the Escrow Agent Agreements constitutes the legal, valid
      and binding obligations of the Escrow Agent enforceable against it in
      accordance with its terms, except as the same may be limited by applicable
      bankruptcy, insolvency, reorganization, moratorium or similar laws
      affecting the rights of creditors generally and by general principles of
      equity, whether considered in a proceeding at law or in equity.

         (f) The Paying Agent represents and warrants that:

         (i) the Paying Agent is duly incorporated, validly existing and in good
      standing under the laws of the State of Delaware and has the full
      corporate power, authority and legal right under the laws of the State of
      Delaware and the United States pertaining to its banking, trust and
      fiduciary powers to execute and deliver this Agreement and the Escrow and
      Paying Agent Agreement (collectively, the "Paying Agent Agreements") and
      to carry out the obligations of the Paying Agent under each of the Paying
      Agent Agreements;

         (ii) the execution and delivery by the Paying Agent of each of the
      Paying Agent Agreements and the performance by the Paying Agent of its
      obligations hereunder and thereunder have been duly authorized by the
      Paying Agent and will not violate its articles of association or by-laws
      or the provisions of any indenture, mortgage, contract or other agreement
      to which it is a party or by which it is bound; and

         (iii) each of the Paying Agent Agreements constitutes the legal, valid
      and binding obligations of the Paying Agent enforceable against it in
      accordance with its terms, except as the same may be limited by applicable
      bankruptcy, insolvency, reorganization, moratorium or similar laws
      affecting the rights of creditors generally and by general principles of
      equity, whether considered in a proceeding at law or in equity.

         SECTION 4. Covenants. (a) The Company covenants with each of the other
parties hereto that:

         (i) (A) on the date that the Depositary is obligated to pay the amount
      of the Final Withdrawals to the Paying Agent pursuant to the Deposit
      Agreements relating to the Class G Trust and the Class C Trust, the
      Company shall pay to the Pass Through Trustee of each such Trust no later
      than 12:30 p.m. (New York time) an amount equal to the Deposit Make-Whole
      Premium, if any, required to be paid in respect of each such Final
      Withdrawal amount, and (B) on the date that the Depositary is obligated to
      pay the amount of the Final Withdrawal to the Paying Agent pursuant to the
      Deposit Agreement relating to the Class D Trust, the Company shall pay to
      the Pass Through Trustee of such Trust no later than 12:30 p.m. (New York
      time) an amount equal to the Deposit Break Amount, if any, and, if such
      date occurs before January 1, 2002, a premium equal to 1% of the amount of
      such Final Withdrawal, in each case, required to be paid in respect of
      such Final Withdrawal amount;
<PAGE>   15
                                                                              12



         (ii) subject to Section 4(a)(iv) of this Agreement, the Company shall
      at all times maintain its corporate existence;

         (iii) the Company shall at all times remain a U.S. Air Carrier (as
      defined in the Financing Agreements) and shall at all times be otherwise
      certificated and registered to the extent necessary to entitle (i) in the
      case of Leased Aircraft, the Owner Trustee (and the Loan Trustee as
      assignee of the Owner Trustee's rights under each Lease) to the rights
      afforded to lessors of aircraft equipment under Section 1110 and (ii) in
      the case of Owned Aircraft, the Loan Trustee to the rights afforded to
      secured parties of aircraft equipment under Section 1110;

         (iv) Section 13.2.1 of each Lease is hereby incorporated by reference
      herein;

         (v) the Company agrees to provide written notice to each of the parties
      hereto of the occurrence of the Cut-off Date no later than one Business
      Day after the date thereof; such notice to refer specifically to the Pass
      Through Trustee's obligation to assign, transfer and deliver all of its
      right, title and interest to the Trust Property (as defined in each Pass
      Through Trust Agreement) to the trustee of the Related Trust (as defined
      in each Pass Through Trust Agreement) in accordance with Section 11.01 of
      each of the Pass Through Trust Agreements;

         (vi) the Company shall not re-issue any Series D Equipment Note
      pursuant to any Owned Aircraft Indenture or Leased Aircraft Indenture
      unless it shall have obtained written confirmation from each Rating Agency
      that the re-issuance of such Series D Equipment Note will not result in
      (i) a reduction of the rating for any Class of Certificates below the then
      current rating for such Class of Certificates (without regard to the
      Policy) or (ii) a withdrawal or suspension of the rating of any Class of
      Certificates; if such condition to the re-issuance of Series D Equipment
      Notes is satisfied, the parties hereto agree to enter into such amendments
      and modifications to the Intercreditor Agreement, the Pass Through Trust
      Agreements and the Financing Agreements (to the extent permitted therein)
      as shall be reasonably requested by the Company to facilitate the
      re-issuance of the same, provided that such amendments and modifications
      shall comply with the Mandatory Document Terms and shall not vary the
      Mandatory Economic Terms (unless such variation would only affect the
      Series D Equipment Notes). The Company will (i) (to the extent such
      documents do not already so provide) cause the Indenture under which any
      Series D Equipment Notes are re-issued and the Intercreditor Agreement to
      provide for the subordination of the Series D Equipment Notes to the
      Series C Equipment Notes, the Policy Provider Obligations (as defined in
      the Intercreditor Agreement), the Series G Equipment Notes and the
      Liquidity Obligations (as defined in the Intercreditor Agreement) in the
      same manner as the initially issued Series D Equipment Notes are
      subordinated to the Series C Equipment Notes, the Policy Provider
      Obligations, the Series G Equipment Notes and the Liquidity Obligations
      and (ii) (A) (to the extent not already so provided) cause such Series D
      Equipment Notes to be subject to the provisions of the Intercreditor
      Agreement that allow for the "Controlling Party" (as defined in the
      Intercreditor Agreement), during the continuance of an "Indenture Event of
      Default" (as defined in the Intercreditor Agreement), to direct the Loan
      Trustee in taking action under the applicable Indenture and (B) (to the
      extent Section 10.9 of the
<PAGE>   16
                                                                              13


      Intercreditor Agreement does not already bind the holders of such
      Series D Equipment Notes) cause the Indenture under which such Series D
      Equipment Notes are re-issued to include, in substance, the provisions set
      forth in Exhibit D to this Agreement. The Class D Trust shall not purchase
      any such re-issued Series D Equipment Notes; and

         (vii) On the Issuance Date, the Depositary's short-term unsecured
      rating shall be A-1+ from Standard & Poor's and P-1 from Moody's (the
      "Depositary Threshold Rating"). If the Depositary's short-term unsecured
      debt rating shall at any time fall below A-1+ from Standard & Poor's or
      P-1 from Moody's, the Company shall, within 45 days of such event
      occurring, cause the Depositary to be replaced with a depository bank (a
      "Replacement Depositary") on the following terms and preconditions:

         (A) the Replacement Depositary must be one that meets the Depositary
      Threshold Rating (unless the Company shall have obtained (i) written
      confirmation from each Rating Agency that such replacement will not cause
      a reduction of any rating then in effect for any Class of Certificates by
      such Rating Agency (without regard to any downgrading of any rating of the
      Depositary being replaced and without regard to the Policy) and (ii) the
      prior written consent of the Policy Provider) and the Company shall have
      obtained written confirmation from each Rating Agency that such
      replacement will not cause a reduction of any rating then in effect for
      any Class of Certificates by such Rating Agency (without regard to any
      downgrading of any rating of the Depositary being replaced and without
      regard to the Policy);

         (B) the Company shall pay all fees, expenses and other amounts then
      owing to the replaced Depositary; and

         (C) the Company shall cause the Escrow Agent and the Replacement
      Depositary to enter into a Replacement Deposit Agreement for each Class of
      Certificates and shall cause the Replacement Depositary to deliver to the
      Company, the Policy Provider and each Rating Agency legal opinions and
      other closing documentation substantially similar in scope and substance
      as those that were delivered by the Depositary being replaced in
      connection with the execution and delivery of the Deposit Agreement being
      replaced.

         Upon satisfaction of the foregoing conditions, the Company shall
      instruct each Pass Through Trustee, and each Pass Through Trustee agrees,
      to execute and deliver to the Escrow Agent a duly completed Withdrawal
      Certificate (as defined in the Escrow and Paying Agent Agreements)
      together with a Notice of Replacement Withdrawal (as defined in the Escrow
      and Paying Agent Agreements).

         Each of the parties hereto agrees, at the Company's request, to enter
      into any amendments to this Agreement, the Escrow and Paying Agent
      Agreements and any other Operative Agreements as may be necessary or
      desirable to give effect to the replacement of the Depositary with the
      Replacement Depositary and the replacement of the Deposit Agreements with
      the Replacement Deposit Agreements.

         Upon the execution and delivery of the Replacement Deposit Agreements,
      the Replacement Depositary shall be deemed to be the Depositary with all
      of the rights and
<PAGE>   17
                                                                              14


      obligations of the Depositary hereunder and under the other Operative
      Agreements and the Replacement Deposit Agreements shall be deemed to be
      the Deposit Agreements hereunder and under the other Operative Agreements,
      except that the obligations of the replaced Depositary under the last two
      sentences of Section 1.4(a) of its Deposit Agreements shall remain in full
      force and effect notwithstanding the execution and delivery of the
      Replacement Deposit Agreements.

         (b) WTC, in its individual capacity, covenants with each of the other
parties to this Agreement that it will, immediately upon obtaining knowledge of
any facts that would cast doubt upon its continuing status as a "citizen of the
United States" as defined in Section 40102 of the Act and promptly upon public
disclosure of negotiations in respect of any transaction which would or might
adversely affect such status, notify in writing all parties hereto of all
relevant matters in connection therewith. Upon WTC giving any such notice, WTC
shall, subject to Section 8.02 of any Indenture then entered into, resign as
Loan Trustee in respect of such Indenture.

         (c) the Subordination Agent covenants with each of the other parties
hereto that it will not agree or consent to any amendment or modification to any
Liquidity Facility, the Policy Provider Agreement or the Intercreditor Agreement
without the Company's consent, if such amendment or modification would adversely
affect the interests of the Company.

         (d) The Escrow Agent covenants with each of the other parties hereto
that it will not agree or consent to any amendment or modification to (i) any
Deposit Agreement or Escrow and Paying Agent Agreement without the Company's
consent, if such amendment or modification would adversely affect the interests
of the Company or (ii) the Deposit Agreement for the Class G Trust or the Escrow
and Paying Agent Agreement for the Class G Trust without the Policy Provider's
consent, if such amendment or modification would adversely affect the interests
of the Policy Provider (such consent not to be unreasonably withheld or
delayed).

         SECTION 5. Notices. Unless otherwise expressly permitted by the terms
hereof, all notices, requests, demands, authorizations, directions, consents,
waivers and other communications required or permitted to be made, given,
furnished or filed hereunder shall be in writing (it being understood that the
specification of a writing in certain instances and not in others does not imply
an intention that a writing is not required as to the latter), shall refer
specifically to this Agreement, and shall be personally delivered, sent by
facsimile or telecommunication transmission (which in either case provides
written confirmation to the sender of its delivery), sent by registered mail or
certified mail, return receipt requested, postage prepaid, or sent by overnight
courier service, in each case to the respective address or facsimile number set
forth for such party below the signature of such party at the foot of this
Agreement, or to such other address, facsimile or other number as each party
hereto may hereafter specify by notice to the other parties hereto. Notice shall
be given to the Policy Provider at the address specified in the Intercreditor
Agreement. Each such notice, request, demand, authorization, direction, consent,
waiver or other communication shall be effective when received or, if made,
given, furnished or filed by facsimile or telecommunication transmission, when
received unless received outside of business hours, in which case on the next
open of business on a Business day.
<PAGE>   18
                                                                              15


         SECTION 6. Expenses. (a) The Company agrees to pay to the Subordination
Agent when due for application in accordance with the Intercreditor Agreement an
amount or amounts equal to the fees payable to the Liquidity Provider under
Section 2.03 of each Liquidity Facility multiplied by a fraction the numerator
of which shall be the then outstanding aggregate amount of the Deposits under
the Deposit Agreements pertaining to the Class G Trust and Class C Trust and the
denominator of which shall be the sum of (x) the then outstanding aggregate
principal amount of the Series G Equipment Notes and Series C Equipment Notes
issued under all of the Indentures and (y) the then outstanding aggregate amount
of the Deposits under the Deposit Agreements pertaining to the Class G Trust and
the Class C Trust.

         (b) The Company agrees to pay to the Subordination Agent when due for
application in accordance with the Intercreditor Agreement an amount or amounts
equal to the fees payable to the Policy Provider under Section 3.02 of the
Policy Provider Agreement multiplied by a fraction the numerator of which shall
be the then outstanding aggregate amount of the Deposits under the Deposit
Agreement pertaining to the Class G Trust and the denominator of which shall be
the sum of (x) the then outstanding aggregate principal amount of the Series G
Equipment Notes issued under all of the Indentures and (y) the then outstanding
aggregate amount of the Deposits under the Deposit Agreement pertaining to the
Class G Trust.

         (c) So long as no Equipment Notes have been issued in respect of any
Aircraft, the Company agrees to pay (i) to the Subordination Agent when due (A)
the amount equal to interest on any Downgrade Advance (other than any Applied
Downgrade Advance) payable under Section 3.07 of each Liquidity Facility minus
Investment Earnings while such Downgrade Advance shall be outstanding, (B) the
amount equal to interest on any Non-Extension Advance (other than any Applied
Non-Extension Advance) payable under Section 3.07 of each Liquidity Facility
minus Investment Earnings while such Non-Extension Advance shall be outstanding
and (C) any other amounts owed to the Liquidity Provider by the Subordination
Agent as borrower under each Liquidity Facility (other than (x) amounts due as
repayment of advances thereunder or as interest on such advances, except to the
extent payable pursuant to clause (A) or (B) and (y) fees payable under Section
6(a) above), (ii) all compensation and reimbursement of expenses, disbursements
and advances payable by the Company under the Pass Through Trust Agreements,
(iii) all compensation and reimbursement of expenses and disbursements payable
to the Subordination Agent under the Intercreditor Agreement (as may be modified
by any separate letter agreement) except with respect to any Unindemnified Taxes
incurred by the Subordination Agent in connection with the transactions
contemplated by the Intercreditor Agreement, (iv) all compensation and
reimbursement of expenses and disbursements payable to the Policy Provider under
the Policy Provider Agreement (except for fees payable under Section 6(b)
above), and (v) in the event the Company requests any amendment to any Operative
Agreement, all reasonable fees and expenses (including, without limitation, fees
and disbursements of counsel) of the Escrow Agent, the Paying Agent and/or the
Policy Provider in connection therewith. For purposes of this Section 6(b), the
terms "Applied Downgrade Advance", "Applied Non-Extension Advance", "Downgrade
Advance", "Investment Earnings" and "Non-Extension Advance" shall have the
meanings specified in each Liquidity Facility.

         SECTION 7. Further Assurances. Each party hereto shall duly execute,
acknowledge and deliver, or shall cause to be executed, acknowledged and
delivered, all such
<PAGE>   19
                                                                              16


further agreements, instruments, certificates or documents, and shall do and
cause to be done such further acts and things, in any case, as any other party
hereto shall reasonably request in connection with its administration of, or to
carry out more effectually the purposes of, or to better assure and confirm unto
it the rights and benefits to be provided under, this Agreement.

         SECTION 8. Miscellaneous. (a) Provided that the transactions
contemplated hereby have been consummated, and except as otherwise provided for
herein, the representations, warranties and agreements herein of the Company,
the Subordination Agent, the Escrow Agent, the Paying Agent and the Pass Through
Trustee, and the Company's, the Subordination Agent's, the Escrow Agent's, the
Paying Agent's and the Pass Through Trustee's obligations under any and all
thereof, shall survive the expiration or other termination of this Agreement and
the other agreements referred to herein.

         (b) This Agreement may be executed in any number of counterparts (and
each of the parties hereto shall not be required to execute the same
counterpart). Each counterpart of this Agreement, including a signature page
executed by each of the parties hereto, shall be an original counterpart of this
Agreement, but all of such counterparts together shall constitute one
instrument. Neither this Agreement nor any of the terms hereof may be
terminated, amended, supplemented, waived or modified orally, but only by an
instrument in writing signed by the party against which the enforcement of the
termination, amendment, supplement, waiver or modification is sought. The index
preceding this Agreement and the headings of the various Sections of this
Agreement are for convenience of reference only and shall not modify, define,
expand or limit any of the terms or provisions hereof. The terms of this
Agreement shall be binding upon, and shall inure to the benefit of, the Company
and its successors and permitted assigns, the Pass Through Trustee and its
successors as Pass Through Trustee (and any additional trustee appointed) under
any of the Pass Through Trust Agreements, the Escrow Agent and its successors as
Escrow Agent under the Escrow and Paying Agent Agreements, the Paying Agent and
its successors as Paying Agent under the Escrow and Paying Agent Agreement and
the Subordination Agent and its successors as Subordination Agent under the
Intercreditor Agreement.

         (c) This Agreement is not intended to, and shall not, provide any
person not a party hereto (other than the Initial Purchasers and each of the
beneficiaries of Section 6 hereof) with any rights of any nature whatsoever
against any of the parties hereto, and no person not a party hereto (other than
the Initial Purchasers and each of the beneficiaries of Section 6 hereof) shall
have any right, power or privilege in respect of, or have any benefit or
interest arising out of, this Agreement. To the extent that this Agreement
expressly confers upon, gives or grants any right, power, privilege, benefit,
interest, remedy or claim to any of the beneficiaries of Section 6 hereof
(including, but not limited to rights, powers, privileges, benefits, interests,
remedies and claims under Section 6) each such party is hereby recognized as a
third party beneficiary hereunder and may enforce any such right, power,
privilege, benefit, interest, remedy or claim.

         SECTION 9. Governing Law. THIS AGREEMENT SHALL BE GOVERNED BY, AND
CONSTRUED IN ACCORDANCE WITH, THE LAW OF THE STATE OF NEW YORK. THIS AGREEMENT
IS BEING DELIVERED IN THE STATE OF NEW YORK.
<PAGE>   20
                                                                              17

                  IN WITNESS WHEREOF, the parties hereto have caused this
Agreement to be duly executed by their respective officers thereunto duly
authorized as of the day and year first above written.

                               AMERICA WEST AIRLINES, INC.


                               By    /s/ Thomas T. Weir
                                  ---------------------------------------------
                                     Name:  Thomas T. Weir
                                     Title: Vice President and Treasurer

                               Address:     4000 East Sky Harbor Boulevard
                                            Phoenix, Arizona 85034
                                            Attention: Vice President
                                               - Treasurer
                                            Facsimile:  (602) 693-5886


                               WILMINGTON TRUST COMPANY,
                               not in its individual capacity, except as
                               otherwise provided herein, but solely as
                               Pass Through Trustee


                               By    /s/ W. Chris Sponenberg
                                  ---------------------------------------------
                                     Name:  W. Chris Sponenberg
                                     Title: Assistant Vice President

                               Address:     Rodney Square North
                                            1100 North Market Street
                                            Wilmington, Delaware 19890
                                            Attention:  Corporate Trust
                                                                 Administration
                                            Facsimile:  (302) 651-8882
<PAGE>   21
                                                                              18



                               WILMINGTON TRUST COMPANY,
                               not in its individual capacity, except as
                               otherwise provided herein, but solely as
                               Subordination Agent


                               By    /s/ W. Chris Sponenberg
                                  ---------------------------------------------
                                     Name:  W. Chris Sponenberg
                                     Title: Assistant Vice President

                               Address:     Rodney Square North
                                            1100 North Market Street
                                            Wilmington, Delaware 19890
                                            Attention:  Corporate Trust
                                                                 Administration
                                            Facsimile:  (302) 651-8882


                               WILMINGTON TRUST COMPANY,
                               as Escrow Agent


                               By    /s/ W. Chris Sponenberg
                                  ---------------------------------------------
                                     Name:  W. Chris Sponenberg
                                     Title: Assistant Vice President

                               Address:     Rodney Square North
                                            1100 North Market Street
                                            Wilmington, Delaware 19890
                                            Attention:  Corporate Trust
                                                                 Administration
                                            Facsimile:  (302) 651-8882


                               WILMINGTON TRUST COMPANY,
                               as Paying Agent

                               By    /s/ W. Chris Sponenberg
                                  ---------------------------------------------
                                     Name:  W. Chris Sponenberg
                                     Title: Assistant Vice President

                               Address:     Rodney Square North
                                            1100 North Market Street
                                            Wilmington, Delaware 19890
                                            Attention:  Corporate Trust
                                                                 Administration
                                            Facsimile:  (302) 651-8882
<PAGE>   22
                                                                              19


                                  SCHEDULE I to
                             Note Purchase Agreement

                     AIRCRAFT AND SCHEDULED DELIVERY MONTHS
<TABLE>
<CAPTION>

                                         Expected                     Expected
                                       Registration                Manufacturer's                  Scheduled
        Aircraft Type                     Number                    Serial Number               Delivery Month
       ---------------                 -------------               ---------------            ----------------
<S>                                    <C>                         <C>                        <C>
       Airbus A319-132                    N824AW                        1490                       May 2001
       Airbus A319-132                    N825AW                        1527                       July 2001
       Airbus A319-132                    N826AW                        1534                       July 2001
       Airbus A319-132                    N827AW                        1547                       July 2001
       Airbus A319-132                    N828AW                        1552                       July 2001
       Airbus A319-132                    N829AW                        1563                      August 2001
       Airbus A319-132                    N830AW                        1565                      August 2001
       Airbus A319-132                    N831AW                        1576                    September 2001
       Airbus A319-132                    N832AW                        1643                     December 2001
       Airbus A320-232                    N664AW                        1621                     November 2001
       Airbus A320-232                    N665AW                        1644                     December 2001
       Airbus A320-232                    N667AW                         TBD                     February 2002
       Airbus A320-232                    N668AW                         TBD                      April 2002
       Airbus A320-232                    N669AW                         TBD                       May 2002
</TABLE>
<PAGE>   23
                                 SCHEDULE II to
                             Note Purchase Agreement

                          PASS THROUGH TRUST AGREEMENTS

Pass Through Trust Agreement dated as of the Issuance Date between the Company
and the Pass Through Trustee in respect of America West Airlines Pass Through
Trust, Series 2001-1G-O.

Pass Through Trust Agreement dated as of the Issuance Date between the Company
and the Pass Through Trustee in respect of America West Airlines Pass Through
Trust, Series 2001-1C-O.

Pass Through Trust Agreement dated as of the Issuance Date between the Company
and the Pass Through Trustee in respect of America West Airlines Pass Through
Trust, Series 2001-1D-O.
<PAGE>   24
                                 SCHEDULE III to
                             Note Purchase Agreement

                               DEPOSIT AGREEMENTS

Deposit Agreement (Class G) dated as of the Issuance Date between the Depositary
and the Escrow Agent.

Deposit Agreement (Class C) dated as of the Issuance Date between the Depositary
and the Escrow Agent.

Deposit Agreement (Class D) dated as of the Issuance Date between the Depositary
and the Escrow Agent.
<PAGE>   25
                                 SCHEDULE IV to
                             Note Purchase Agreement

                       ESCROW AND PAYING AGENT AGREEMENTS

Escrow and Paying Agent Agreement (Class G) dated as of the Issuance Date among
the Escrow Agent, the Initial Purchasers, the Pass Through Trustee and the
Paying Agent.

Escrow and Paying Agent Agreement (Class C) dated as of the Issuance Date among
the Escrow Agent, the Initial Purchasers, the Pass Through Trustee and the
Paying Agent.

Escrow and Paying Agent Agreement (Class D) dated as of the Issuance Date among
the Escrow Agent, the Initial Purchasers, the Pass Through Trustee and the
Paying Agent.
<PAGE>   26
                                  SCHEDULE V to
                             Note Purchase Agreement

                            MANDATORY DOCUMENT TERMS

The terms "Trust Indenture Form", "Lease Form" and "Participation Agreement
Form" shall have the respective meanings specified in Schedule VI to the Note
Purchase Agreement.

1.       May not modify in any material adverse respect the Granting Clause of
         the Trust Indenture Form so as to deprive the Note Holders of a
         security interest in and mortgage lien on the Aircraft, certain rights
         under the Aircraft Purchase Agreement and, in the case of a Leased
         Aircraft Indenture, the Lease or to eliminate any of the "Secured
         Obligations" as defined therein or otherwise modify in any material
         adverse respect as regards the interests of the Note Holders, the
         Subordination Agent, the Liquidity Provider, the Policy Provider or the
         Mortgagee the provisions of Article II or III or in the case of a
         Leased Aircraft Indenture Section 4.02, 4.03, 4.04, 5.02, 5.06,
         9.01(b), 10.04, 10.11 or 10.12 of the Trust Indenture Form or in the
         case of an Owned Aircraft Indenture Article IV, Section 5.01, 5.02,
         6.02, 10.01, 11.04, 11.11 or 11.12 of the Trust Indenture Form.

2.       May not modify in any material adverse respect as regards the interests
         of the Note Holders, the Subordination Agent, the Liquidity Provider,
         the Policy Provider or the Mortgagee the provisions of Section
         3.2.1(e), 3.3(c), 4.7, the final sentence of 7.1.1, 10.3.1(d)(ii),
         13.3, 16, 17.3, 18.3 or 18.6(a) of the Lease Form or otherwise modify
         the terms of the Lease Form so as to deprive the Mortgagee of rights
         expressly granted to the "Mortgagee" therein.

3.       May not modify in any material adverse respect as regards the interests
         of the Note Holders, the Subordination Agent, the Liquidity Provider or
         the Mortgagee the provisions of Section (Owned Aircraft Section
         references shown in '[ ]') 5.1.9[3.1.7], 5.1.10[3.1.8], 5.1.11[3.1.9],
         5.1.12[3.1.10], 7.5[5.3], 12[9], 15.7(a)[11.7(a)] or 15.9[11.9] of the
         Participation Agreement Form or of the provisions of Section
         5.1.2(xxiii)[, 3.1.2(xvi)] or 10.1.1(a)(iv) of the Participation
         Agreement Form so as to eliminate the requirement to deliver to the
         Loan Participant or the Mortgagee, as the case may be, the legal
         opinions to be provided to such Persons thereunder (recognizing that
         the lawyers rendering such opinions may be changed) or of the
         provisions of Section 7.6.11(a)(ii)[5.4.5(a)(ii)] of the Participation
         Agreement Form as regards the rights of the Mortgagee thereunder or of
         the provisions of Section 5.1.16[3.1.14] of the Participation Agreement
         Form so as to deprive the Note Holders of a first priority security
         interest as provided therein in and mortgage lien on the Aircraft and
         the Lease or otherwise modify the terms of the Participation Agreement
         Form to deprive the Trustees, the Subordination Agent, the Liquidity
         Providers or the Mortgagee of any indemnity or right of reimbursement
         in its favor for Expenses or Taxes.

4.       May not modify, in any material adverse respect as regards the
         interests of the Note Holders, the Subordination Agent, the Liquidity
         Providers or the Mortgagee, the definition of "Make Whole Amount" and
         "Break Amount" in Annex A to the Participation Agreement Form.
<PAGE>   27
                                                                               2

         Notwithstanding the foregoing, any such Mandatory Document Term may be
modified to correct or supplement any such provision which may be defective or
to cure any ambiguity or correct any mistake, provided that any such action
shall not materially adversely affect the interests of the Note Holders, the
Subordination Agent, the Liquidity Providers, the Policy Provider, the Mortgagee
or the Certificateholders.
<PAGE>   28
                                 SCHEDULE VI to
                             Note Purchase Agreement

                            MANDATORY ECONOMIC TERMS

Equipment Notes

Obligor:                                   America West Airlines, Inc. or an
                                           Owner Trust

Maximum Principal Amount:                  the maximum principal amount of all
                                           the Equipment Notes issued with
                                           respect to an Aircraft may not exceed
                                           the maximum principal amount of
                                           Equipment Notes indicated for each
                                           such Aircraft as set forth in
                                           "Offering Memorandum Summary --
                                           Equipment Notes and the Aircraft"
                                           under the column "Maximum Principal
                                           Amount of Equipment Notes";

Initial Average Life:                      the average life per aircraft of the
                                           Series G Equipment Notes shall not be
                                           less than 10.0 years nor more than
                                           14.0 years, of the Series C Equipment
                                           Notes shall not be less than 3.0
                                           years nor more than 5.0 years and of
                                           the Series D Equipment Notes shall
                                           not be more than 3.5 years, in each
                                           case from the Issuance Date.
                                           Additionally, in the case of the
                                           Series D Equipment Notes, scheduled
                                           payments of principal to begin on or
                                           after April 2, 2002;

Average Life (in years):                   as of the first Regular Distribution
                                           Date following the delivery of the
                                           last Aircraft to be delivered, the
                                           average life of the Class G
                                           Certificates not to be less than 11.8
                                           years nor more than 12.2 years, of
                                           the Class C Certificates not to be
                                           less than 3.9 years nor more than 4.1
                                           years, and of the Class D
                                           Certificates not to be more than 3.0
                                           years, in each case from the Issuance
                                           Date;

Loan to Aircraft Value:                    the loan to aircraft value ratio with
                                           respect to each Aircraft at the time
                                           of issuance of the related Equipment
                                           Notes and on any Regular Distribution
                                           Date thereafter shall not exceed
                                           53.6% in the case of the Series G
                                           Equipment Notes, 63.0% in the case of
                                           the Series C Equipment Notes and
                                           72.5% in the case of the Series D
                                           Equipment Notes (in each case
                                           computed on the basis of an assumed
                                           value of such Aircraft no greater
                                           than the value for such Aircraft set
                                           forth under "Offering Memorandum
                                           Summary -- Equipment Notes and the
                                           Aircraft" under the column "Appraised
                                           Value" and the depreciation
                                           assumption contained in footnote 1 in
                                           the chart under "Offering Memorandum
                                           Summary -- Loan to Aircraft Value
                                           Ratios")

Final Maturity Date:                       the final maturity date of (a) the
                                           Series G Equipment Notes may not be
                                           extended beyond April 2, 2021, (b)
                                           the Series C Equipment Notes may not
                                           be extended beyond April 2, 2007
<PAGE>   29
                                           and (c) the Series D Equipment Notes
                                           may not be extended beyond October 2,
                                           2005;

Principal Amount:                          At the Delivery Period Termination
                                           Date, the aggregate principal amount
                                           of all Series G Equipment Notes to be
                                           equal to the aggregate face amount of
                                           the Class G Certificates, the
                                           aggregate principal amount of all
                                           Series C Equipment Notes not to
                                           exceed, but may be less than, the
                                           original aggregate face amount of the
                                           Class C Certificates (it being
                                           understood that the Pool Balance (as
                                           defined in the Intercreditor
                                           Agreement) of the Class C
                                           Certificates at such date shall be
                                           reduced to the extent it exceeds the
                                           aggregate principal amount of all
                                           Series C Equipment Notes) and the
                                           aggregate principal amount of all
                                           Series D Equipment Notes not to
                                           exceed, but may be less than, the
                                           original aggregate face amount of the
                                           Class D Certificates (it being
                                           understood that the Pool Balance (as
                                           defined in the Intercreditor
                                           Agreement) of the Class D
                                           Certificates at such date shall be
                                           reduced to the extent it exceeds the
                                           aggregate principal amount of all
                                           Series D Equipment Notes);

Debt Rate:                                 the interest rate applicable to each
                                           Series of Equipment Notes must be
                                           equal to the rate applicable to the
                                           Certificates issued by the
                                           corresponding Pass Through Trust;

Payment Due Rate:                          Debt Rate plus 1% per annum

Payment Dates:                             April 2 and October 2 commencing with
                                           the first such date after the
                                           applicable Equipment Notes are issued

Make-Whole Premiums/Break Amounts:         as provided in Article II of the form
                                           of Trust Indenture marked as Exhibits
                                           A-3 and C-2 of the Note Purchase
                                           Agreement (the "Trust Indenture
                                           Form")

Redemption and Purchase:                   as provided in Article II of the
                                           Trust Indenture Form

All-risk hull insurance:                   Not less than the unpaid principal
                                           amount of the related Equipment Notes
                                           together with six months of accrued
                                           Interest.

Lease Term:                                The Base Lease Term shall expire by
                                           its terms on or after final maturity
                                           date of the related Series G or
                                           Series C Equipment Notes

Lease Payment Dates:                       April 2 and October 2 commencing with
                                           the first such date after the Lease
                                           is entered into, to and including the
                                           last such

                                       2
<PAGE>   30
                                           date in the Term

Minimum Rent:                              Basic Rent due and payable on each
                                           Payment Date shall be at least
                                           sufficient to pay in full, as of such
                                           Payment Date (assuming timely payment
                                           of the related Equipment Notes prior
                                           to such Date), the aggregate
                                           principal amount of scheduled
                                           installments due on the related
                                           Equipment Notes outstanding on such
                                           Payment Date together with accrued
                                           and unpaid interest thereon

Supplemental Rent:                         Sufficient to cover the sums
                                           described in clauses (a) through (d)
                                           of such term as defined in Annex A to
                                           the form of Lease (the "Lease Form")
                                           marked as Exhibit A-2 of the Note
                                           Purchase Agreement

EBO Amount (if any):                       At all times equal to or greater than
                                           the then outstanding principal amount
                                           of the related Equipment Notes
                                           together with accrued interest
                                           thereon

Stipulated Loss Value:                     At all times equal to or greater than
                                           the then outstanding principal amount
                                           of the related Equipment Notes
                                           together with accrued interest
                                           thereon

Termination Value:                         At all times equal to or greater than
                                           the then outstanding principal amount
                                           of the related Equipment Notes
                                           together with accrued interest
                                           thereon

All-risk hull insurance:                   not less than Stipulated Loss Value,
                                           subject to Lessee's right to
                                           self-insure on terms no more
                                           favorable to Lessee in any material
                                           respect than those set forth in Annex
                                           D of the form of Lease marked as
                                           Exhibit A-2.

Minimum Liability Insurance Amount:        as set forth in Schedule 1 to the
                                           form of Lease marked as Exhibit A-2.

Payment Due Rate:                          as set forth in Annex A to the form
                                           of Lease marked as Exhibit A-2.

SLV Rate:                                  as set forth in Schedule 1 to the
                                           form of Lease marked as Exhibit A-2.


Participation Agreement

Mortgagee, Subordination Agent, Liquidity Providers, the Policy Provider, Pass
Through Trustees, and Escrow Agents indemnified against Expenses and Taxes to
the extent set forth in

                                       3
<PAGE>   31
Section 9 of the form of the Participation Agreement (the "Participation
Agreement Form") marked as Exhibits A-1 and C-1 to the Note Purchase Agreement


                                       4
<PAGE>   32
                                 SCHEDULE VII to
                             Note Purchase Agreement

                         AGGREGATE AMORTIZATION SCHEDULE

<TABLE>
<CAPTION>
                                    2001-1G Trust                     2001-1C Trust                      2001-1D Trust
          Date               Scheduled Principal Payment       Scheduled Principal Payment        Scheduled Principal Payment
----------------------       ---------------------------       ---------------------------        ---------------------------
<S>                          <C>                               <C>                                <C>
October 2, 2001.......               $1,867,092.00                      $2,595,002.24             $                 0.00
April 2, 2002.........                3,691,735.52                       1,755,144.00                        3,140,00.00
October 2, 2002.......               17,892,441.08                         390,672.40                       4,528,400.00
April 2, 2003.........                2,811,970.50                         131,340.30                       4,800,104.00
October 2, 2003.......                6,450,964.20                       4,386,452.63                       5,088,110.24
April 2, 2004.........                2,811,970.50                       4,957,115.01                       5,393,396.85
October 2, 2004.......                6,450,964.20                       7,062,596.00                       5,717,000.67
April 2, 2005.........                2,811,970.50                       2,064,346.07                       6,060,020.71
October 2, 2005.......                6,450,964.20                      11,404,268.00                      10,272,967.53
April 2, 2006.........                9,262,934.70                      11,404,268.00                               0.00
October 2, 2006.......                        0.00                       4,341,672.00                               0.00
April 2, 2007.........                4,882,887.90                       6,528,123.35                               0.00
October 2, 2007.......                4,380,046.80                               0.00                               0.00
April 2, 2008.........                2,811,970.50                               0.00                               0.00
October 2, 2008.......                7,906,500.60                               0.00                               0.00
April 2, 2009.........                1,356,434.10                               0.00                               0.00
October 2, 2009.......                6,450,964.20                               0.00                               0.00
April 2, 2010.........                9,864,878.10                               0.00                               0.00
October 2, 2010.......               14,045,772.80                               0.00                               0.00
April 2, 2011.........               14,780,412.50                               0.00                               0.00
October 2, 2011.......                2,062,956.80                               0.00                               0.00
April 2, 2012.........                2,062,956.80                               0.00                               0.00
October 2, 2012.......               15,970,553.77                               0.00                               0.00
October 2, 2013.......                4,217,638.06                               0.00                               0.00
April 2, 2014.........                4,769,856.95                               0.00                               0.00
October 2, 2014.......               11,281,926.69                               0.00                               0.00
April 2, 2015.........               11,965,664.00                               0.00                               0.00
October 2, 2015.......               14,045,772.80                               0.00                               0.00
April 2, 2016.........               23,948,480.00                               0.00                               0.00
April 2, 2017.........                9,902,707.20                               0.00                               0.00
October 2, 2017.......               11,965,664.00                               0.00                               0.00
April 2, 2018.........               11,965,664.00                               0.00                               0.00
April 2, 2019.........                9,902,707.20                               0.00                               0.00
October 2, 2019.......               19,950,389.85                               0.00                               0.00
April 2, 2020.........               14,216,144.09                               0.00                               0.00
October 2, 2020.......               16,108,729.60                               0.00                               0.00
April 2, 2021.........               13,822,313.29                               0.00                               0.00
</TABLE>


                                       5
<PAGE>   33
                                   ANNEX A to
                             Note Purchase Agreement

                                   DEFINITIONS

"Act" means 49 U.S.C.Sections 40101-46507.

"Adjusted Treasury Yield" means the Treasury Yield plus, in the case of a
distribution to holders of Class G Certificates, 180 basis points, and, in the
case of a distribution to holders of Class C Certificates, 365 basis points.

"Affiliate" means, with respect to any person, any other person directly or
indirectly controlling, controlled by or under common control with such person.
For purposes of this definition, "control" means the power, directly or
indirectly, to direct or cause the direction of the management and policies of
such person, whether through the ownership of voting securities or by contract
or otherwise and "controlling," "controlled by" and "under common control with"
have correlative meanings.

"Aircraft" has the meaning set forth in the second recital to the Note Purchase
Agreement.

"Aircraft Purchase Agreement" means the Airbus A319/A320 Purchase Agreement,
dated as of September 12, 1997, between the Company and the Manufacturer
(including all exhibits thereto, together with all letter agreements entered
into that by their terms constitute part of any such Purchase Agreement).

"Aircraft Purchase Agreement Assignment" means an Assignment and Delegation
Agreement substantially in the form of Exhibit A-4 to the Note Purchase
Agreement.

"Assumed Amortization Schedule" means Schedule VII to the Note Purchase
Agreement.

"Average Life Date" means, for any Equipment Note, the date which follows the
time of determination by a period equal to the Remaining Weighted Average Life
of such Equipment Note.

"Bankruptcy Code" means the United States Bankruptcy Code, 11 U.S.C.Sections 101
et seq.

"Business Day" means any day, other than a Saturday, Sunday or other day on
which commercial banks are authorized or required by law to close in New York,
New York, Phoenix, Arizona, Hartford, Connecticut or Wilmington, Delaware.

"Certificate" has the meaning set forth in the third recital to the Note
Purchase Agreement.

"Certificateholder" means the Person in whose name a Certificate is registered
in the Register.

"Class" means the class of Certificates issued by each Pass Through Trust.

"Class C Certificates" has the meaning specified in the Intercreditor Agreement.

"Class C Trust" has the meaning specified in the Intercreditor Agreement
<PAGE>   34
                                                                               2

"Class D Certificates" has the meaning specified in the Intercreditor Agreement.

"Class D Trust" has the meaning specified in the Intercreditor Agreement

"Class G Certificates" has the meaning specified in the Intercreditor Agreement.

"Class G Trust " has the meaning specified in the Intercreditor Agreement.

"Company" means America West Airlines, Inc., a Delaware corporation.

"Corporate Trust Office" with respect to any Pass Through Trustee or any Loan
Trustee, means the office of such trustee in the city at which at any particular
time its corporate trust business shall be principally administered.

"Cut-off Date" means the earlier of (a) the day after the Delivery Period
Termination Date and (b) the date on which a Triggering Event occurs.

"Delivery Period Termination Date" means the earlier of (a) August 30, 2002, or,
if the Equipment Notes relating to all of the Aircraft (or Substitute Aircraft
in lieu thereof) have not been purchased by the Pass Through Trustees on or
prior to such date due to any reason beyond the control of the Company and not
occasioned by the Company's fault or negligence, November 30, 2002 and (b) the
date on which Equipment Notes issued with respect to all of the Aircraft (or
Substitute Aircraft in lieu thereof) have been purchased by the Pass Through
Trustees in accordance with the Note Purchase Agreement.

"Delivery Date" means the Business Day on which an Aircraft is delivered to and
accepted by the Company or otherwise becomes subject to any Financing Agreement.

"Deposit" has the meaning set forth in the fifth recital to the Note Purchase
Agreement.

"Deposit Agreement" shall mean the initial Deposit Agreements set forth on
Schedule III hereto and, from and after the transfer of the Deposits to a
Replacement Depositary, shall refer to the corresponding Replacement Deposit
Agreements between the Escrow Agent and the Replacement Depositary.

"Deposit Break Amount" means, as of any date of distribution of remaining
Deposits relating to the Class D Trust (the "Applicable Date"), an amount
determined by the Class D Trustee on the date that is two LIBOR Business Days
prior to the Applicable Date pursuant to the formula set forth below.

                  The Deposit Break Amount will be calculated as follows:

                  Deposit Break Amount = Z-Y

                  Where:

         X =    with respect to any applicable interest period, the sum of (i)
                the amount of such remaining Deposits as of the Applicable Date
                plus (ii) interest payable thereon
<PAGE>   35
                                                                               3

                during such entire interest period at then effective Six-Month
                LIBOR.

         Y      = X, discounted to present value from the last day of the then
                applicable interest period to the Applicable Date, using then
                effective Six-Month LIBOR as the discount rate.

         Z      = X, discounted to present value from the last day of the then
                applicable interest period to the Applicable Date, using a rate
                equal to the applicable London interbank offered rate for a
                period commencing on the Applicable Date and ending on the last
                day of the then applicable interest period, determined by the
                Class D Trustee as of two LIBOR Business Days prior to the
                Applicable Date as the discount rate.

No Deposit Break Amount will be payable (x) if the Deposit Break Amount, as
calculated pursuant to the formula set forth above, is equal to or less than
zero or (y) on or in respect of any Applicable Date that is a Regular
Distribution Date.

"Deposit Make-Whole Premium" means, with respect to the distribution of unused
Deposits to holders of the Class G Certificates and the Class C Certificates, as
of any date of determination, an amount equal to the excess, if any, of (a) the
present value of the excess of (i) the scheduled payment of principal and
interest to maturity of the Series G Equipment Notes and Series C Equipment
Notes, assuming the maximum principal amount thereof (as permitted by the
Mandatory Economic Terms) were issued with respect to all of the Aircraft (the
"Maximum Amount") minus any Non-Premium Amount applicable to such Class of
Certificates and, in the case of Class C Certificates only, the Par Redemption
Amount, on each remaining Regular Distribution Date for such Class under the
Assumed Amortization Schedule over (ii) the scheduled payment of principal and
interest to maturity of the Series G Equipment Notes and Series C Equipment
Notes actually acquired by the Pass Through Trustee for such Class on each such
Regular Distribution Date, such present value computed by discounting such
excess on a semiannual basis on each Regular Distribution Date (assuming a
360-day year of twelve 30-day months) using a discount rate equal to the
Adjusted Treasury Yield over (b) the amount of such unused Deposits to be
distributed to the holders of such Certificates minus any Non-Premium Amount
applicable to such Class of Certificates and, in the case of Class C
Certificates only, the Par Redemption Amount (the remainder of such subtraction,
the "Net Deposits") plus accrued and unpaid interest on the Net Deposits to but
excluding such date of determination from and including the preceding Regular
Distribution Date (or if such date of determination precedes the first Regular
Distribution Date, the Issuance Date).

"Depositary" means Citibank, N.A., a national banking association, and, from and
after the transfer of the Deposits to a Replacement Depositary, shall mean such
Replacement Depositary.

"Equipment Notes" means and includes any equipment notes issued under any
Indenture in the form specified in Section 2.01 thereof (as such form may be
varied pursuant to the terms of such Indenture) and any Equipment Note issued
under any Indenture in exchange for or replacement of any other Equipment Note.

"Escrow Agent" has the meaning set forth in the first paragraph of the Note
Purchase Agreement.
<PAGE>   36
                                                                               4

"Escrow and Paying Agent Agreement" has the meaning set forth in the fifth
recital to the Note Purchase Agreement.

"FAA" means the Federal Aviation Administration of the United States.

"Final Withdrawal" with respect to each Escrow and Paying Agent Agreement, has
the meaning set forth in Section 1.02 thereof.

"Financing Agreements" means, collectively, the Lease Financing Agreements and
the Owner Financing Agreements.

"Government Entity" means (a) any federal, state, provincial or similar
government, and any body, board, department, commission, court, tribunal,
authority, agency or other instrumentality of any such government or otherwise
exercising any executive, legislative, judicial, administrative or regulatory
functions of such government or (b) any other government entity having
jurisdiction over any matter contemplated by the Operative Agreements or
relating to the observance or performance of the obligations of any of the
parties to the Operative Agreements.

"H.15(519)" means the weekly statistical release designated as such, or any
successor publication, published by the Board of Governors of the Federal
Reserve System.

"Indentures" means, collectively, the Leased Aircraft Indentures and the Owned
Aircraft Indentures.

"Initial Purchasers" has the meaning set forth in the fourth recital to the Note
Purchase Agreement.

"Intercreditor Agreement" has the meaning set forth in the ninth recital to the
Note Purchase Agreement.

"Issuance Date" means the date of the original issuance of the Certificates.

"Law" means (a) any constitution, treaty, statute, law, decree, regulation,
order, rule or directive of any Government Entity, and (b) any judicial or
administrative interpretation or application of, or decision under, any of the
foregoing.

"Lease" means a Lease Agreement substantially in the form of Exhibit A-2 to the
Note Purchase Agreement.

"Lease Financing Agreements" means, collectively, the Aircraft Purchase
Agreement Assignment, the Leased Aircraft Participation Agreement, the Lease,
the Leased Aircraft Indenture, the Equipment Notes issued thereunder and the
Trust Agreement relating to the financing of a Leased Aircraft.

"Leased Aircraft" means an Aircraft subject to a Lease.

"Leased Aircraft Indenture" means a Trust Indenture and Mortgage substantially
in the form of Exhibit A-3 to the Note Purchase Agreement.
<PAGE>   37
                                                                              5

"Leased Aircraft Participation Agreement" means a Participation Agreement
substantially in the form of Exhibit A-1 to the Note Purchase Agreement.

"LIBOR Business Day" means any day on which dealings are carried on in the
London interbank market.

"Liquidity Facility" has the meaning set forth in the ninth recital to the Note
Purchase Agreement.

"Liquidity Provider" has the meaning set forth in the tenth recital to the Note
Purchase Agreement.

"Loan Trustee" means the "Mortgagee" as defined in the Financing Agreements.

"Mandatory Document Terms" means the terms set forth on Schedule V to the Note
Purchase Agreement.

"Mandatory Economic Terms" means the terms set forth on Schedule VI to the Note
Purchase Agreement.

"Manufacturer" means Airbus Industrie G.I.E., solely in its capacity as
manufacturer or seller of Aircraft.

"Material Adverse Change" means, with respect to any Person, any event,
condition or circumstance that materially and adversely affects such Person 's
business or consolidated financial condition or its ability to observe or
perform its obligations, liabilities and agreements under the Operative
Agreements.

"Non-Premium Amount" means, with respect to the Class G Certificates and the
Class C Certificates, if any Aircraft has not been delivered by the Manufacturer
on or prior to the Delivery Period Termination Date due to any reason not
occasioned by the Company's fault or negligence and no Substitute Aircraft has
been provided in lieu of such Aircraft, an amount equal to the maximum principal
amount of Equipment Notes with respect to such Aircraft that could have been
issued and acquired by the Pass Through Trust that issued such Class of
Certificates in accordance with the Mandatory Economic Terms. "Note Holder"
means at any time each registered holder of one or more Equipment Notes.

"Note Purchase Agreement" means the Note Purchase Agreement to which this Annex
A is attached.

"Notice of Purchase Withdrawal" with respect to each Deposit Agreement, has the
meaning set forth in Section 2.3 thereof.

"Operative Agreements" means, collectively, the Pass Through Trust Agreements,
the Escrow and Paying Agent Agreements, the Deposit Agreements, the Liquidity
Facilities, the Policy Provider Agreement, the Policy, the Intercreditor
Agreement, the Registration Rights Agreement, the Trust Agreements, the
Equipment Notes, the Certificates and the Financing Agreements.
<PAGE>   38
                                                                               6

"Owned Aircraft Indenture" means a Trust Indenture and Mortgage substantially in
the form of Exhibit C-2 to the Note Purchase Agreement.

"Owned Aircraft Participation Agreement" means a Participation Agreement
substantially in the form of Exhibit C-1 to the Note Purchase Agreement.

"Owner Financing Agreements" means, collectively, the Owned Aircraft
Participation Agreement, the Owned Aircraft Indenture and the Equipment Notes
issued thereunder.

"Owner Participant" means, with respect to any Leased Aircraft, the Person named
as the Owner Participant in the Participation Agreement with respect to such
Leased Aircraft.

"Owner Trust" means with respect to any Leased Aircraft, the trust created by
the "Trust Agreement" referred to in the Leased Aircraft Indenture related
thereto.

"Owner Trustee" means with respect to any Leased Aircraft, the "Owner Trustee"
party to the "Trust Agreement" referred to in the Leased Aircraft Indenture
related thereto.

"Par Redemption Amount" means $10 million.

"Participation Agreements" means, collectively, the Leased Aircraft
Participation Agreements and the Owned Aircraft Participation Agreements.

"Pass Through Trust" has the meaning set forth in the third recital to the Note
Purchase Agreement.

"Pass Through Trust Agreement" has the meaning set forth in the third recital to
the Note Purchase Agreement.

"Pass Through Trustee" has the meaning set forth in the first paragraph of the
Note Purchase Agreement.

"Paying Agent" has the meaning set forth in the first paragraph of the Note
Purchase Agreement.

"Person" means any individual, firm, partnership, joint venture, trust, trustee,
Government Entity, organization, association, corporation, limited liability
company, government agency, committee, department, authority and other body,
corporate or incorporate, whether having distinct legal status or not, or any
member of any of the same.

"Policy " has the meaning set forth in the tenth recital to the Note Purchase
Agreement.

"Policy Obligations" has the meaning specified in the Intercreditor Agreement.

"Policy Provider" has the meaning set forth in the tenth recital to the Note
Purchase Agreement.

"Policy Provider Agreement" has the meaning set forth in the tenth recital to
the Note Purchase Agreement.
<PAGE>   39
                                                                               7

"Qualified Owner Participant" means any bank, trust company, insurance company,
financial institution, limited liability company, partnership or corporation, in
each case with a combined capital and surplus or net worth of at least
$50,000,000.

"Rating Agencies" means, collectively, at any time, each nationally recognized
rating agency which shall have been requested to rate the Certificates and which
shall then be rating the Certificates. The initial Rating Agencies will be
Moody's Investors Service, Inc. and Standard & Poor's Rating Services, a
division of The McGraw-Hill Companies Inc.

"Rating Agency Confirmation" means, with respect to any action proposed to be
taken, a written confirmation from each of the Rating Agencies that such action
would not result in (i) a reduction of the rating for any Class of Certificates
below the then current rating for such Class of Certificates (without regard to
the Policy) or (ii) a withdrawal or suspension of the rating of any Class of
Certificates.

"Register" means the register maintained pursuant to Sections 3.04 and 7.12 of
each Pass Through Trust Agreement.

"Registration Rights Agreement" means the Exchange and Registration Rights
Agreement dated as of the Issuance Date, among the Initial Purchasers, the Pass
Through Trustees and the Company, as amended, supplemented or otherwise modified
from time to time in accordance with its terms.

"Regular Distribution Dates" shall mean April 2 and October 2 of each year,
commencing October 2, 2001.

"Remaining Weighted Average Life" means, on a given date with respect to any
Equipment Note, the number of days equal to the quotient obtained by dividing
(a) the sum of each of the products obtained by multiplying (i) the amount of
each then remaining scheduled payment of principal of such Equipment Note by
(ii) the number of days from and including such determination date to but
excluding the date on which such payment of principal is scheduled to be made,
by (b) the then outstanding principal amount of such Equipment Note.

"Replacement Depositary" has the meaning set forth in Section 4(a)(vii) of the
Note Purchase Agreement.

"Replacement Deposit Agreement" means, for each Class of Certificates, a deposit
agreement substantially in the form of the replaced Deposit Agreement for such
Class of Certificates as shall permit the Rating Agencies to confirm in writing
their respective ratings then in effect for such Class of Certificates (before
the downgrading of such ratings, if any, as a result of the downgrading of the
Depositary and without regard to the Policy).

"Scheduled Delivery Date" has the meaning set forth in Section 1(b) hereof.

"Section 1110" means 11 U.S.C. Section 1110 of the Bankruptcy Code or any
successor or analogous Section of the federal bankruptcy Law in effect from time
to time.
<PAGE>   40
                                                                               8

"Series C Equipment Notes" means Equipment Notes issued under an Indenture and
designated as "Series C" thereunder.

"Series D Equipment Notes" means Equipment Notes issued under an Indenture and
designated as "Series D" thereunder.

"Series G Equipment Notes" means Equipment Notes issued under an Indenture and
designated as "Series G" thereunder.

"Subordination Agent" has the meaning set forth in the first paragraph of the
Note Purchase Agreement.

"Substitute Aircraft" has the meaning set forth in Section 1(f) of the Note
Purchase Agreement.

"Taxes" means all license, recording, documentary, registration and other
similar fees and all taxes, levies, imposts, duties, charges, assessments or
withholdings of any nature whatsoever imposed by any Taxing Authority, together
with any penalties, additions to tax, fines or interest thereon or additions
thereto.

"Taxing Authority" means any federal, state or local government or other taxing
authority in the United States, any foreign government or any political
subdivision or taxing authority thereof, any international taxing authority or
any territory or possession of the United States or any taxing authority
thereof.

"Treasury Yield" means, as of any date of determination, with respect to any
Equipment Note (utilizing the Assumed Amortization Schedule applicable thereto),
the interest rate (expressed as a decimal and, in the case of United States
Treasury bills, converted to a bond equivalent yield) determined to be the per
annum rate equal to the semi-annual yield to maturity for United States Treasury
securities maturing on the Average Life Date (of such Equipment Note) and
trading in the public securities markets either as determined by interpolation
between the most recent weekly average yield to maturity for two series of
United States Treasury securities, trading in the public securities markets, (A)
one maturing as close as possible to, but earlier than, the Average Life Date
(of such Equipment Note) and (B) the other maturing as close as possible to, but
later than, the Average Life Date (of such Equipment Note), in each case as
published in the most recent H.15(519) or, if a weekly average yield to maturity
for United States Treasury securities maturing on the Average Life Date (of such
Equipment Note) is reported on the most recent H.15(519), such weekly average
yield to maturity as published in such H.15(519).

"Triggering Event" has the meaning assigned to such term in the Intercreditor
Agreement.

"Trust Agreement" means a Trust Agreement substantially in the form of Exhibit
A-5 to the Note Purchase Agreement.

"Unindemnified Taxes" has the meaning assigned to such term in the Intercreditor
Agreement.

"WTC" has the meaning set forth in the first paragraph of the Note Purchase
Agreement.
<PAGE>   41
                                 EXHIBIT A-1 to
                             Note Purchase Agreement

                 FORM OF LEASED AIRCRAFT PARTICIPATION AGREEMENT
<PAGE>   42
                                 EXHIBIT A-2 to
                             Note Purchase Agreement

                                  FORM OF LEASE
<PAGE>   43
                                 EXHIBIT A-3 to
                             Note Purchase Agreement

                        FORM OF LEASED AIRCRAFT INDENTURE
<PAGE>   44
                                 EXHIBIT A-4 to
                             Note Purchase Agreement

                 FORM OF AIRCRAFT PURCHASE AGREEMENT ASSIGNMENT
<PAGE>   45
                                 EXHIBIT A-5 to
                             Note Purchase Agreement

                     FORM OF LEASED AIRCRAFT TRUST AGREEMENT
<PAGE>   46
                                  EXHIBIT B to
                             Note Purchase Agreement

                             FORM OF DELIVERY NOTICE

                         Dated as of __________ __, ____

To each of the addressees listed

         in Schedule A hereto

         Re:      Delivery Notice in accordance with Note Purchase Agreement
                  referred to below

Gentlemen:

         Reference is made to the Note Purchase Agreement dated as of
[________], 2001 among America West Airlines, Inc. (the "Company"), Wilmington
Trust Company, as Pass Through Trustee under each of the Pass Through Trust
Agreements (as defined therein) (the "Pass Through Trustee"), Wilmington Trust
Company, as Subordination Agent (the "Subordination Agent"), Wilmington Trust
Company, as Escrow Agent (the "Escrow Agent") and Wilmington Trust Company, as
Paying Agent (the "Paying Agent") (as in effect from time to time, the "Note
Purchase Agreement"). Unless otherwise defined herein, capitalized terms used
herein shall have the meanings set forth in the Note Purchase Agreement or, to
the extent not defined therein, the Intercreditor Agreement.

         Pursuant to Section 1(b) of the Note Purchase Agreement, the
undersigned hereby notifies you, in respect of the Airbus ___ aircraft with
manufacturer's serial number _______ (the "Aircraft"), of the following:

(1)      The Company has elected to treat the Aircraft as [a Leased](1)/[an
         Owned](2) Aircraft;

(2)      The Scheduled Delivery Date of the Aircraft is __________ __, ____; and

(3)      The aggregate amount of each series of Equipment Notes to be issued,
         and purchased by the respective Pass Through Trustees, on the Scheduled
         Delivery Date, in connection with the financing of such Aircraft is as
         follows:

         (a)      the Class G Trustee shall purchase Series G Equipment Notes in
                  the amount of $__________;

         (b)      the Class C Trustee shall purchase Series C Equipment Notes in
                  the amount of $__________; and

--------------
1        To be inserted in the case of a Leased Aircraft.

2        To be inserted in the case of an Owned Aircraft.
<PAGE>   47
                                                                               2

         (c)      the Class D Trustee shall purchase Series D Equipment Notes in
                  the amount of $_______.

         The Company hereby instructs the Class G Trustee to (i) execute a
Withdrawal Certificate in the form of Annex A hereto dated _____ __, ____ [a
date which is no later than one Business Day prior to the Scheduled Delivery
Date] and attach thereto a Notice of Purchase Withdrawal dated such date
completed as set forth on Exhibit A hereto and (ii) deliver such Withdrawal
Certificate and Notice of Purchase Withdrawal to the applicable Escrow Agent.

         The Company hereby instructs the Class C Trustee to (i) execute a
Withdrawal Certificate in the form of Annex A hereto dated _____ __, ____ [a
date which is no later than one Business Day prior to the Scheduled Delivery
Date] and attach thereto a Notice of Purchase Withdrawal dated such date
completed as set forth on Exhibit B hereto and (ii) deliver such Withdrawal
Certificate and Notice of Purchase Withdrawal to the applicable Escrow Agent.

         The Company hereby instructs the Class D Trustee to (i) execute a
Withdrawal Certificate in the form of Annex A hereto dated _____ __, ____ [a
date which is no later than one Business Day prior to the Scheduled Delivery
Date] and attach thereto a Notice of Purchase Withdrawal dated such date
completed as set forth on Exhibit C hereto and (ii) deliver such Withdrawal
Certificate and Notice of Purchase Withdrawal to the applicable Escrow Agent.

         The Company hereby instructs each Pass Through Trustee to (i) purchase
Equipment Notes of a series and in an amount set forth opposite such Pass
Through Trustee in clause (3) above with a portion of the proceeds of the
withdrawals of Deposits referred to in the applicable Notice of Purchase
Withdrawal referred to above and (ii) re-deposit with the Depositary the excess,
if any, of the amount so withdrawn over the purchase price of such Equipment
Notes.

         The Company hereby instructs each Pass Through Trustee to (a) enter
into the Participation Agreement dated as of _____ __, ____ among the Company,
as [Lessee](3)/[Owner](4), the Subordination Agent, the Pass Through Trustee,
___________________, as Mortgagee [and Loan Participant, _____________________,
as Owner Trustee and _________, as Owner Participant](5), (b) perform its
obligations thereunder and (c) deliver such certificates, documents and legal
opinions relating to such Pass Through Trustee as required thereby.

         [The Company hereby certifies that the Owner Participant with respect
to the Aircraft is (a) not an Affiliate of the Company and (b) a [Qualified
Owner Participant/person whose

-----------

3        To be inserted in the case of a Leased Aircraft.

4        To be inserted in the case of an Owned Aircraft.

5        To be inserted in the case of a Leased Aircraft.
<PAGE>   48
                                                                               3

obligations under the Owner Participant Agreements (as defined in the
Participation Agreement) are guaranteed by a Qualified Owner Participant].](6)

Yours faithfully,

America West Airlines, Inc.

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

-----------

6        To be inserted in the case of a Leased Aircraft.
<PAGE>   49
                                   SCHEDULE A



Wilmington Trust Company, as
   Pass Through Trustee, Subordination
   Agent, Escrow Agent and Paying Agent
Rodney Square North
1100 North Market Street
Wilmington, Delaware 19890
Attention: Corporate Trust
           Administration
Facsimile: (302) 651-8882

Standard & Poor's Ratings Services
55 Water Street, 35th Floor
New York, New York  10041
Attention:  Betsy R. Snyder
Facsimile:  (212) 438-7811

Moody's Investors Service, Inc.
99 Church Street
New York, New York  10007
Attention:  Richard Bittenbender
Facsimile:  (212) 553-4661
<PAGE>   50
                                                                         ANNEX A

                             WITHDRAWAL CERTIFICATE

                                  (Class __)(7)

                            WILMINGTON TRUST COMPANY,
                                 as Escrow Agent

Dear Sirs:

                  Reference is made to the Escrow and Paying Agent Agreement,
dated as of [________], 2001 (the "Agreement"). We hereby certify to you that
the conditions to the obligations of the undersigned to execute a Participation
Agreement pursuant to the Note Purchase Agreement have been satisfied. Pursuant
to Section 1.02(c) of the Agreement, please execute the attached Notice of
Withdrawal and immediately transmit by facsimile to the Depositary, at (212)
657-3866, Attention: Global Agency & Trust.

                                    Very truly yours,

                                    WILMINGTON TRUST COMPANY, not in its
                                    individual capacity by solely as Pass
                                    Through Trustee



                                    By:______________________________________
                                          Name:
                                          Title:

Dated: _______ __, 200_


--------------------------

7        Insert letter of appropriate class of Certificates.
<PAGE>   51
                                                                       EXHIBIT A

                          NOTICE OF PURCHASE WITHDRAWAL



Citibank, N.A.
111 Wall Street
14th floor, Zone 3
New York, NY 10005
Attention:  Global Agency & Trust
Telecopier:  213-657-3866


Gentlemen:

         Reference is made to the Deposit Agreement (Class G) dated as of
[______], 2001 (the "Deposit Agreement") between Wilmington Trust Company, as
Escrow Agent, and Citibank, N.A., as Depositary (the "Depositary").

         In accordance with Section 1.5(a) of the Deposit Agreement, the
undersigned hereby requests the withdrawal of the entire amount of the Deposit,
$_______, Account No. ____________.

         The undersigned hereby directs the Depositary to pay the proceeds of
the Deposit to [________________, Account No. _____, Reference: _________] on
_________ __, 200_, upon the telephonic request of a representative of
Wilmington Trust Company, the Pass Through Trustee.


                                         WILMINGTON TRUST COMPANY,
                                         as Escrow Agent



                                         By: __________________________________
                                               Name:
                                               Title:



Dated: _______ __, 200_
<PAGE>   52
                                                                       EXHIBIT B

                          NOTICE OF PURCHASE WITHDRAWAL



Citibank, N.A.
111 Wall Street
14th floor, Zone 3
New York, New York  10005
Attention:  Global Agency & Trust
Telecopier:  213-657-3866


Gentlemen:

         Reference is made to the Deposit Agreement (Class C) dated as of
[______], 2001 (the "Deposit Agreement") between Wilmington Trust Company, as
Escrow Agent, and Citibank, N.A., as Depositary (the "Depositary").

         In accordance with Section 1.5(a) of the Deposit Agreement, the
undersigned hereby requests the withdrawal of the entire amount of the Deposit,
$_______, Account No. ____________.

         The undersigned hereby directs the Depositary to pay the proceeds of
the Deposit to [________________, Account No. _____, Reference: _________] on
_________ __, 200_, upon the telephonic request of a representative of the
Wilmington Trust Company, Pass Through Trustee.

                                             WILMINGTON TRUST COMPANY,
                                             as Escrow Agent



                                             By:_______________________________
                                                   Name:
                                                   Title:

Dated: _______ __, 200_
<PAGE>   53
                                                                       EXHIBIT C


                          NOTICE OF PURCHASE WITHDRAWAL


Citibank, N.A.
111 Wall Street
14th floor, Zone 3
New York, New York  10005
Attention:  Global Agency & Trust
Telecopier:  213-657-3866

Gentlemen:

         Reference is made to the Deposit Agreement (Class D) dated as of
[_______], 2001 (the "Deposit Agreement") between Wilmington Trust Company, as
Escrow Agent, and Citibank, N.A., as Depositary (the "Depositary").

         In accordance with Section 1.5(a) of the Deposit Agreement, the
undersigned hereby requests the withdrawal of the entire amount of the Deposit,
$_______, Account No. ____________.

         The undersigned hereby directs the Depositary to pay the proceeds of
the Deposit to [________________, Account No. _____, Reference: _________] on
_________ __, 200_, upon the telephonic request of a representative of the
Wilmington Trust Company, Pass Through Trustee.

                                          WILMINGTON TRUST COMPANY,
                                          as Escrow Agent



                                          By:__________________________________
                                                Name:
                                                Title:

Dated: _______ __, 200_
<PAGE>   54
                                 EXHIBIT C-1 to
                             Note Purchase Agreement

                 FORM OF OWNED AIRCRAFT PARTICIPATION AGREEMENT
<PAGE>   55
                                 EXHIBIT C-2 to
                             Note Purchase Agreement

                        FORM OF OWNED AIRCRAFT INDENTURE
<PAGE>   56
                                  EXHIBIT D to
                             Note Purchase Agreement

             ADDITIONAL SUBORDINATION PROVISION FOR THE RE-ISSUANCE
                         OF THE SERIES D EQUIPMENT NOTES

                  Subordination.

                  (a)      As between the Note Holders, this Trust Indenture
                           shall be a subordination agreement for purposes of
                           Section 510 of the United States Bankruptcy Code, as
                           amended, from time to time.

                  (b)      If any Note Holder receives any payment in respect of
                           any obligations owing hereunder, which is
                           subsequently invalidated, declared preferential, set
                           aside and/or required to be repaid to a trustee,
                           receiver or other party, then, to the extent of such
                           payment, such obligations intended to be satisfied
                           shall be revived and continue in full force and
                           effect as if such payment had not been received.

                  (c)      Each of the Note Holders may take any of the
                           following actions without impairing its rights under
                           this Trust Indenture:

                           (i)      obtain a Lien on any property to secure any
                                    amounts owing to it hereunder,

                           (ii)     obtain the primary or secondary obligation
                                    of any other obligor with respect to any
                                    amounts owing to it hereunder,

                           (iii)    renew, extend, increase, alter or exchange
                                    any amounts owing to it hereunder, or
                                    release or compromise any obligation of any
                                    obligor with respect thereto,

                           (iv)     refrain from exercising any right or remedy,
                                    or delay in exercising such right or remedy,
                                    which it may have, or

                           (v)      take any other action which might discharge
                                    a subordinated party or a surety under
                                    applicable law;

                  provided, however, that the taking of any such actions by any
                  of the Note Holders shall not prejudice the rights or
                  adversely affect the obligations of any other party under this
                  Trust Indenture.