<PAGE>   1
                                                                    Exhibit 4.18


                                                                       EXECUTION



                        ESCROW AND PAYING AGENT AGREEMENT
                                    (Class A)

                           Dated as of October 6, 1998

                                      among

                            WILMINGTON TRUST COMPANY
                                 as Escrow Agent

                       MORGAN STANLEY & CO. INCORPORATED,
               DONALDSON, LUFKIN & JENRETTE SECURITIES CORPORATION
               MERRILL LYNCH, PIERCE, FENNER & SMITH INCORPORATED
                                       and
                            SALOMON SMITH BARNEY INC.

                              as Initial Purchasers

                            WILMINGTON TRUST COMPANY,
                         not in its individual capacity,
                       but solely as Pass Through Trustee
                              for and on behalf of
               America West Airlines Pass Through Trust 1998-1A-O

                             as Pass Through Trustee

                                       and

                            WILMINGTON TRUST COMPANY

                                 as Paying Agent
<PAGE>   2
                                TABLE OF CONTENTS

<TABLE>
<CAPTION>
                                                                          Page
                                                                          ----
<S>                                                                       <C>
SECTION 1.    Escrow Agent............................................      2


Section 1.01. Appointment of Escrow Agent.............................      2


Section 1.02. Instruction; Etc........................................      3


Section 1.03. Initial Escrow Amount; Issuance of Escrow
              Receipts................................................      4


Section 1.04. Payments to Receiptholders..............................      5


Section 1.05. Mutilated, Destroyed, Lost or Stolen Escrow Receipt.....      5


Section 1.06. Additional Escrow Amounts...............................      6


Section 1.07. Resignation or Removal of Escrow Agent..................      6


Section 1.08. Persons Deemed Owners...................................      7


Section 1.09. Further Assurances......................................      7


SECTION 2.    Paying Agent............................................      7


Section 2.01. Appointment of Paying Agent.............................      7


Section 2.02. Establishment of Paying Agent Account...................      8


Section 2.03. Payments from Paying Agent Account......................      8


Section 2.04. Withholding Taxes.......................................      9


Section 2.05. Resignation or Removal of Paying Agent..................     11
</TABLE>


                                       i
<PAGE>   3
<TABLE>
<CAPTION>
                                                                          Page
                                                                          ----
<S>                                                                       <C>
Section 2.06. Notice of Final Withdrawal..............................     11


SECTION 3.    Payments................................................     12


SECTION 4.    Other Actions...........................................     12


SECTION 5.    Representations and Warranties of the
              Escrow Agent............................................     12


SECTION 6.    Representations and Warranties of the
              Paying Agent............................................     14


SECTION 7.    Indemnification.........................................     15


SECTION 8.    Amendment, Etc..........................................     16


SECTION 9.    Notices.................................................     16


SECTION 10.   Transfer................................................     17


SECTION 11.   Entire Agreement........................................     18


SECTION 12.   Governing Law...........................................     18


SECTION 13.   Waiver of Jury Trial Right..............................     18


SECTION 14.   Counterparts............................................     18
</TABLE>


Exhibit A     Escrow Receipt

Exhibit B     Withdrawal Certificate


                                       ii
<PAGE>   4
            ESCROW AND PAYING AGENT AGREEMENT (Class A) dated as of October 6,
1998 (as amended, modified or supplemented from time to time, this "Agreement")
among WILMINGTON TRUST COMPANY, a Delaware banking corporation, as Escrow Agent
(in such capacity, together with its successors in such capacity, the "Escrow
Agent"); MORGAN STANLEY & CO. INCORPORATED, DONALDSON, LUFKIN & JENRETTE
SECURITIES CORPORATION, MERRILL LYNCH, PIERCE, FENNER & SMITH INCORPORATED and
SALOMON SMITH BARNEY INC., as Initial Purchasers of the Certificates referred to
below (the "Initial Purchasers" and together with their respective transferees
and assigns as registered owners of the Certificates, the "Investors") under the
Purchase Agreement referred to below; Wilmington Trust Company, 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 the Pass
Through Trust Agreement referred to below; and WILMINGTON TRUST COMPANY, a
Delaware banking corporation, as paying agent hereunder (in such capacity,
together with its successors in such capacity, the "Paying Agent").

                               W I T N E S S E T H

            WHEREAS, America West Airlines, Inc. ("America West") and the Pass
Through Trustee have entered into a Pass Through Trust Agreement, dated as of
October 6, 1998 (together, as amended, modified or supplemented from time to
time in accordance with the terms thereof, the "Pass Through Trust Agreement")
relating to America West Airlines Pass Through Trust 1998-1A-O (the "Pass
Through Trust") pursuant to which the America West Airlines Pass Through Trust,
Series 1998-1A-O Certificates referred to therein (the "Certificates") are being
issued;

            WHEREAS, America West and the Initial Purchasers have entered into a
Purchase Agreement dated as of September 24, 1998 (as amended, modified or
supplemented from time to time in accordance with the terms thereof, the
"Purchase Agreement") pursuant to which the Pass Through Trustee will issue and
sell the Certificates to the Initial Purchasers (the net proceeds of such sale
being herein referred to as the "Net Proceeds");

            WHEREAS, America West, the Pass Through Trustee, certain other pass
through trustees and certain other persons concurrently herewith are entering
into the Note Purchase Agreement, dated as of the date hereof (the "Note
Purchase
<PAGE>   5
                                                                               2


Agreement"), pursuant to which the Pass Through Trustee has agreed to acquire
from time to time on or prior to the Delivery Period Termination Date (as
defined in the Note Purchase Agreement) equipment notes (the "Equipment Notes")
issued to finance or refinance the acquisition of aircraft by America West, as
lessee or as owner, utilizing a portion of the Net Proceeds;

            WHEREAS, the Initial Purchasers and the Pass Through Trustee intend
that the Net Proceeds be held in escrow by the Escrow Agent on behalf of the
Investors, subject to withdrawal upon request by the Pass Through Trustee and
satisfaction of the conditions set forth in the Note Purchase Agreement for the
purpose of purchasing Equipment Notes, and that pending such withdrawal the Net
Proceeds be deposited on behalf of the Escrow Agent with ABN AMRO Bank N.V.,
acting through its Chicago branch, as Depositary (the "Depositary") under the
Deposit Agreement, dated as of the date hereof between the Depositary and the
Escrow Agent relating to the Pass Through Trust (as amended, modified or
supplemented from time to time in accordance with the terms thereof, the
"Deposit Agreement") pursuant to which, among other things, the Depositary will
pay interest for distribution to the Investors and establish accounts from which
the Escrow Agent shall make withdrawals upon request of and proper certification
by the Pass Through Trustee;

            WHEREAS, the Escrow Agent wishes to appoint the Paying Agent to pay
amounts required to be distributed to the Investors in accordance with this
Agreement; and

            WHEREAS, capitalized terms used but not defined herein shall have
the meanings ascribed to such terms in the Pass Through Trust Agreement.

            NOW, THEREFORE, in consideration of the obligations contained
herein, and for other good and valuable consideration, the receipt and
sufficiency of which is hereby acknowledged, the parties hereto hereby agree as
follows:

            SECTION 1.  Escrow Agent.

            Section 1.01. Appointment of Escrow Agent. Each of the Initial
Purchasers, for and on behalf of each of the Investors, hereby irrevocably
appoints, authorizes and directs the Escrow Agent to act as escrow agent and
fiduciary hereunder and under the Deposit Agreement for such specific purposes
and
<PAGE>   6
                                                                               3


with such powers as are specifically delegated to the Escrow Agent by the terms
of this Agreement, together with such other powers as are reasonably incidental
thereto. Any and all money received and held by the Escrow Agent under this
Agreement or the Deposit Agreement shall be held in escrow by the Escrow Agent
in accordance with the terms of this Agreement. This Agreement is irrevocable
and the Investors' rights with respect to any monies received and held in escrow
by the Escrow Agent under this Agreement or the Deposit Agreement shall only be
as provided under the terms and conditions of this Agreement and the Deposit
Agreement. The Escrow Agent (which term as used in this sentence shall include
reference to its affiliates and its own and its affiliates' officers, directors,
employees and agents): (a) shall have no duties or responsibilities except those
expressly set forth in this Agreement; (b) shall not be responsible to the Pass
Through Trustee or the Investors for any recitals, statements, representations
or warranties of any person other then itself contained in this Agreement or the
Deposit Agreement or for the failure by the Pass Through Trustee, the Investors
or any other person or entity (other than the Escrow Agent) to perform any of
its obligations hereunder (whether or not the Escrow Agent shall have any
knowledge thereof); and (c) shall not be responsible for any action taken or
omitted to be taken by it hereunder or provided for herein or in connection
herewith, except for its own willful misconduct or gross negligence (or simple
negligence in connection with the handling of funds) or breach of its
obligations hereunder.

            Section 1.02. Instruction; Etc. The Initial Purchasers, for and on
behalf of each of the Investors, hereby irrevocably instruct the Escrow Agent,
and the Escrow Agent agrees, (a) to enter into the Deposit Agreement, (b) to
appoint the Paying Agent as provided in this Agreement, (c) upon receipt at any
time and from time to time prior to the Termination Date (as defined below) of a
certificate substantially in the form of Exhibit B hereto (a "Withdrawal
Certificate") executed by the Pass Through Trustee, together with an attached
Notice of Purchase Withdrawal in substantially the form of Exhibit A to the
Deposit Agreement duly completed by the Pass Through Trustee (the "Applicable
Notice of Purchase Withdrawal" and the withdrawal to which it relates, a
"Purchase Withdrawal"), immediately to execute the Applicable Notice of Purchase
Withdrawal as Escrow Agent and transmit it to the Depositary by facsimile
transmission in accordance with the Deposit Agreement; provided that, upon the
request of the Pass Through Trustee after such transmission, the Escrow Agent
shall cancel such
<PAGE>   7
                                                                               4


Applicable Notice of Purchase Withdrawal, and (d) if there are any undrawn
Deposits (as defined in the Deposit Agreement) on the "Termination Date", which
shall mean the earlier of (i) February 1, 2000 and (ii) the day on which the
Escrow Agent receives notice from the Pass Through Trustee that the Pass Through
Trustee's obligation to purchase Equipment Notes under the Note Purchase
Agreement has terminated, to give notice to the Depositary (with a copy to the
Paying Agent) substantially in the form of Exhibit B to the Deposit Agreement
requesting a withdrawal of all of the remaining Deposits, together with accrued
and unpaid interest on such Deposits to the date of withdrawal, on the 35th day
after the date that such notice of withdrawal is given to the Depositary (or, if
not a Business Day, on the next succeeding Business Day) (a "Final Withdrawal"),
provided that if the day scheduled for the Final Withdrawal in accordance with
the foregoing is within 10 days before or after a Regular Distribution Date,
then the Escrow Agent shall request that such requested Final Withdrawal be made
on such Regular Distribution Date (the date of such requested withdrawal, the
"Final Withdrawal Date"). If for any reason the Escrow Agent shall have failed
to give the Final Withdrawal Notice to the Depositary on or before February 7,
2000, and there are unwithdrawn Deposits on such date, the Final Withdrawal Date
shall be deemed to be February 28, 2000.

            Section 1.03. Initial Escrow Amount; Issuance of Escrow Receipts.
The Escrow Agent hereby directs the Initial Purchasers to, and the Initial
Purchasers hereby acknowledge that on the date hereof they shall, irrevocably
deliver to the Depositary on behalf of the Escrow Agent, an amount in U.S.
dollars ("Dollars") and immediately available funds equal to $131,670,000 for
deposit on behalf of the Escrow Agent with the Depositary in accordance with
Section 2.1 of the Deposit Agreement. The Initial Purchasers hereby instruct the
Escrow Agent, upon receipt of such sum from the Initial Purchasers, to confirm
such receipt by executing and delivering to the Pass Through Trustee an Escrow
Receipt in the form of Exhibit A hereto (an "Escrow Receipt"), (a) to be affixed
by the Pass Through Trustee to each Certificate and (b) to evidence the same
percentage interest (the "Escrow Interest") in the Account Amounts (as defined
below) as the Fractional Undivided Interest in the Pass Through Trust evidenced
by the Certificate to which it is to be affixed. The Escrow Agent shall provide
to the Pass Through Trustee for attachment to each Certificate newly issued
under and in accordance with the Pass Through Trust Agreement an executed Escrow
Receipt as the Pass Through Trustee may from
<PAGE>   8
                                                                               5


time to time request of the Escrow Agent. Each Escrow Receipt shall be
registered by the Escrow Agent in a register (the "Register") maintained by the
Escrow Agent in the same name and same manner as the Certificate to which it is
attached and may not thereafter be detached from such Certificate to which it is
to be affixed prior to the distribution of the Final Withdrawal (the "Final
Distribution"). After the Final Distribution, no additional Escrow Receipts
shall be issued and the Pass Through Trustee shall request the return to the
Escrow Agent for cancellation of all outstanding Escrow Receipts.

            Section 1.04. Payments to Receiptholders. All payments and
distributions made to holders of an Escrow Receipt (collectively
"Receiptholders") in respect of the Escrow Receipt shall be made only from
amounts deposited in the Paying Agent Account (as defined below) ("Account
Amounts"). Each Receiptholder, by its acceptance of an Escrow Receipt, agrees
that (a) it will look solely to the Account Amounts for any payment or
distribution due to such Receiptholder pursuant to the terms of the Escrow
Receipt and this Agreement and (b) it will have no recourse to America West, the
Pass Through Trustee, the Paying Agent, the Escrow Agent or Wilmington Trust
Company, except as expressly provided herein or in the Pass Through Trust
Agreement. No Receiptholder shall have any right to vote or in any manner
otherwise control the operation and management of the Paying Agent Account or
the obligations of the parties hereto, nor shall anything set forth herein, or
contained in the terms of the Escrow Receipt, be construed so as to constitute
the Receiptholders from time to time as partners or members of an association.

            Section 1.05. Mutilated, Destroyed, Lost or Stolen Escrow Receipt.
If (a) any mutilated Escrow Receipt is surrendered to the Escrow Agent or the
Escrow Agent receives evidence to its satisfaction of the destruction, loss or
theft of any Escrow Receipt and (b) there is delivered to the Escrow Agent and
the Pass Through Trustee such security, indemnity or bond, as may be required by
them to hold each of them harmless, then, absent notice to the Escrow Agent or
the Pass Through Trustee that such destroyed, lost or stolen Escrow Receipt has
been acquired by a bona fide purchaser, and provided that the requirements of
Section 8-405 of the Uniform Commercial Code in effect in any applicable
jurisdiction are met, the Escrow Agent shall execute, authenticate and deliver,
in exchange for or in lieu of any such mutilated, destroyed, lost or stolen
Escrow Receipt, a new Escrow Receipt or Escrow Receipts and of like
<PAGE>   9
                                                                               6


Escrow Interest in the Account Amounts and bearing a number not
contemporaneously outstanding.

            In connection with the issuance of any new Escrow Receipt under this
Section 1.05, the Escrow Agent may require the payment of a sum sufficient to
cover any tax or other governmental charge that may be imposed in relation
thereto and any other expenses (including the fees and expenses of the Pass
Through Trustee and the Escrow Agent) connected therewith.

            Any duplicate Escrow Receipt issued pursuant to this Section 1.05
shall constitute conclusive evidence of the appropriate Escrow Interest in the
Account Amounts, as if originally issued, whether or not the lost, stolen or
destroyed Escrow Receipt shall be found at any time.

            The provisions of this Section are exclusive and shall preclude (to
the extent lawful) all other rights and remedies with respect to the replacement
or payment of mutilated, destroyed, lost or stolen Escrow Receipts.

            Section 1.06. Additional Escrow Amounts. On the date of any Purchase
Withdrawal, the Pass Through Trustee may re-deposit with the Depositary some or
all of the amounts so withdrawn in accordance with Section 2.4 of the Deposit
Agreement.

            Section 1.07. Resignation or Removal of Escrow Agent. Subject to the
appointment and acceptance of a successor Escrow Agent as provided below, the
Escrow Agent may resign at any time by giving 30 days' prior written notice
thereof to the Investors, but may not otherwise be removed except for cause by
the written consent of the Investors with respect to Investors representing
Escrow Interests aggregating not less than a majority in interest in the Account
Amounts (an "Action of Investors"). Upon any such resignation or removal, the
Investors, by an Action of Investors, shall have the right to appoint a
successor Escrow Agent. If no successor Escrow Agent shall have been so
appointed and shall have accepted such appointment within 30 days after the
retiring Escrow Agent's giving of notice of resignation or the removal of the
retiring Escrow Agent, then the retiring Escrow Agent may appoint a successor
Escrow Agent. Any successor Escrow Agent shall be a bank which has an office in
the United States with a combined capital and surplus of at least $100,000,000.
Upon the acceptance of any appointment as Escrow Agent hereunder by a
<PAGE>   10
                                                                               7


successor Escrow Agent, such successor Escrow Agent shall enter into such
documents as the Pass Through Trustee shall require and shall thereupon succeed
to and become vested with all the rights, powers, privileges and duties of the
retiring Escrow Agent, and the retiring Escrow Agent shall be discharged from
its duties and obligations hereunder. No resignation or removal of the Escrow
Agent shall be effective unless a written confirmation shall have been obtained
from each of Moody's Investors Service, Inc. and Standard & Poor's Rating
Services, a division of The McGraw-Hill Companies, Inc., that the replacement of
the Escrow Agent with the successor Escrow Agent will not result in (a) a
reduction of the rating for the Certificates below the then current rating for
the Certificates or (b) a withdrawal or suspension of the rating of the
Certificates.

            Section 1.08. Persons Deemed Owners. Prior to due presentment of a
Certificate for registration of transfer, the Escrow Agent and the Paying Agent
may treat the Person in whose name any Escrow Receipt is registered (as of the
day of determination) as the owner of such Escrow Receipt for the purpose of
receiving distributions pursuant to this Agreement and for all other purposes
whatsoever, and neither the Escrow Agent nor the Paying Agent shall be affected
by any notice to the contrary.

            Section 1.09. Further Assurances. The Escrow Agent agrees to take
such actions, and execute such other documents, as may be reasonably requested
by the Pass Through Trustee in order to effectuate the purposes of this
Agreement and the performance by the Escrow Agent of its obligations hereunder.

            SECTION 2. Paying Agent.

            Section 2.01. Appointment of Paying Agent. The Escrow Agent hereby
irrevocably appoints and authorizes the Paying Agent to act as its paying agent
hereunder, for the benefit of the Investors, for such specific purposes and
with such powers as are specifically delegated to the Paying Agent by the terms
of this Agreement, together with such other powers as are reasonably incidental
thereto. Any and all money received and held by the Paying Agent under this
Agreement or the Deposit Agreement shall be held in the Paying Agent Account for
the benefit of the Investors. The Paying Agent (which term as used in this
sentence shall include reference to its affiliates and its own and its
affiliates' officers, directors, employees and
<PAGE>   11
                                                                               8


agents): (a) shall have no duties or responsibilities except those expressly set
forth in this Agreement, and shall not by reason of this Agreement be a trustee
for the Escrow Agent; (b) shall not be responsible to the Escrow Agent for any
recitals, statements, representations or warranties of any person other then
itself contained in this Agreement or for the failure by the Escrow Agent or any
other person or entity (other than the Paying Agent) to perform any of its
obligations hereunder (whether or not the Paying Agent shall have any knowledge
thereof); and (c) except in respect of its express obligations hereunder, shall
not be responsible for any action taken or omitted to be taken by it hereunder
or provided for herein or in connection herewith, except for its own willful
misconduct or gross negligence (or simple negligence in connection with the
handling of funds).

            Section 2.02. Establishment of Paying Agent Account. The Paying
Agent shall establish a deposit account (the "Paying Agent Account") at
Wilmington Trust Company in the name of the Escrow Agent. It is expressly
understood by the parties hereto that the Paying Agent is acting as the paying
agent of the Escrow Agent hereunder and that no amounts on deposit in the Paying
Agent Account constitute part of the Trust Property.

            Section 2.03. Payments from Paying Agent Account. The Escrow Agent
hereby irrevocably instructs the Paying Agent, and the Paying Agent agrees to
act, as follows:

            (a) On each Interest Payment Date (as defined in the Deposit
      Agreement) or as soon thereafter as the Paying Agent has confirmed receipt
      in the Paying Agent Account from the Depositary of any amount in respect
      of accrued interest on the Deposits, the Paying Agent shall distribute out
      of the Paying Agent Account the entire amount deposited therein by the
      Depositary. There shall be so distributed to each Receiptholder of record
      on the 15th day (whether or not a Business Day) preceding such Interest
      Payment Date by check mailed to such Receiptholder, at the address
      appearing in the Register, such Receiptholder's pro rata share (based on
      the Escrow Interest in the Account Amounts held by such Receiptholder) of
      the total amount of interest deposited by the Depositary in the Paying
      Agent Account on such date, except that, with respect to Escrow Receipts
      registered on the Record Date in the name of DTC, such distribution shall
      be made by wire transfer in immediately available funds to the account
      designated by DTC.
<PAGE>   12
                                                                               9


            (b) Upon the confirmation by the Paying Agent of receipt in the
      Paying Agent Account from the Depositary of any amount in respect of the
      Final Withdrawal, the Paying Agent shall forthwith distribute the entire
      amount of the Final Withdrawal deposited therein by the Depositary. There
      shall be so distributed to each Receiptholder of record on the 15th day
      (whether or not a Business Day) preceding the Final Withdrawal Date by
      check mailed to such Receiptholder, at the address appearing in the
      Register, such Receiptholder's pro rata share (based on the Escrow
      Interest in the Account Amounts held by such Receiptholder) of the total
      amount in the Paying Agent Account on account of such Final Withdrawal,
      except that, with respect to Escrow Receipts registered on the Record Date
      in the name of DTC, such distribution shall be made by wire transfer in
      immediately available funds to the account designated by DTC.

            (c) If any payment of interest or principal in respect of the Final
      Withdrawal is not received by the Paying Agent within five days of the
      applicable date when due, then it shall be distributed to Receiptholders
      after actual receipt by the Paying Agent on the same basis as a Special
      Payment is distributed under the Pass Through Trust Agreement.

            (d) The Paying Agent shall include with any check mailed pursuant to
      this Section any notice required to be distributed under the Pass Through
      Trust Agreement that is furnished to the Paying Agent by the Pass Through
      Trustee.

            Section 2.04. Withholding Taxes. The Paying Agent shall exclude and
withhold from each distribution of accrued interest on the Deposits (as defined
in the Deposit Agreement) and any amount in respect of the Final Withdrawal any
and all withholding taxes applicable thereto as required by law. In addition,
the Paying Agent shall remit or cause to be remitted such amounts as would be
required by Section 1446 of the Internal Revenue Code of 1986, as amended, as if
the agreements of the Initial Purchasers set forth in this Agreement were
characterized as a partnership engaged in a U.S. trade or business for U.S.
federal income tax purposes and shall withhold or cause to be withheld such
amounts from amounts distributable to or for the benefit of Receiptholders or
beneficial owners of interests in Escrow Receipts that are not United States
persons
<PAGE>   13
                                                                              10


within the meaning of section 7701(a)(30) of the Internal Revenue Code of 1986,
as amended ("Non-U.S. Persons"). In this regard, the Paying Agent shall cause
the appropriate withholding agent to withhold with respect to such distributions
in the manner contemplated by Section 10.04 of Revenue Procedure 89-31 and
Treasury Regulation 1.1445-8(b)(3)) by filing a notice with the National
Association of Securities Dealers, Inc. substantially in the form of Exhibits C
and D on or before the date 10 days prior to the Record Date. The Paying Agent
shall mail such notice to the National Association of Securities Dealers no
later than the date 15 days prior to the Record Date. Investors that are not
United States Persons agree to furnish a taxpayer identification number ("TIN")
to the Paying Agent and the Paying Agent shall provide such TINs to the
appropriate U.S. withholding agent. The Paying Agent agrees to act as such
withholding agent (except to the extent contemplated above with respect to
withholding amounts as if the agreements of the Initial Purchasers as set forth
in this Agreement were characterized as a business engaged in a U.S. trade or
business for U.S. federal income tax purposes) and, in connection therewith,
whenever any present or future taxes or similar charges are required to be
withheld with respect to any amounts payable in respect of the Deposits (as
defined in the Deposit Agreement) or the escrow amounts, to withhold such
amounts and timely pay the same to the appropriate authority in the name of and
on behalf of the Receiptholders, that it will file any necessary withholding tax
returns or statements when due, and that, as promptly as possible after the
payment thereof, it will deliver to each such Receiptholder appropriate
documentation showing the payment thereof, together with such additional
documentary evidence as such Receiptholder may reasonably request from time to
time. The Paying Agent agrees to file any other information reports as it may be
required to file under United States law.

            Each Receiptholder or beneficial owner of an interest in an Escrow
Receipt that is a Non-U.S. Person, by its acceptance of an Escrow Receipt or a
beneficial interest therein, agrees to indemnify and hold harmless the Escrow
Agent and the Paying Agent from and against any improper failure to withhold
Taxes from amounts payable to it or for its benefit other than an improper
failure attributable to the gross negligence or willful misconduct of the Escrow
Agent or the Paying Agent, as the case may be.
<PAGE>   14
                                                                              11


            Section 2.05. Resignation or Removal of Paying Agent. Subject to the
appointment and acceptance of a successor Paying Agent as provided below, the
Paying Agent may resign at any time by giving 30 days' prior written notice
thereof to the Escrow Agent, but may not otherwise be removed except for cause
by the Escrow Agent. Upon any such resignation or removal, the Escrow Agent
shall have the right to appoint a successor Paying Agent. If no successor Paying
Agent shall have been so appointed and shall have accepted such appointment
within 30 days after the retiring Paying Agent's giving of notice of resignation
or the removal of the retiring Paying Agent, then the retiring Paying Agent may
appoint a successor Paying Agent. Any Successor Paying Agent shall be a bank
which has an office in the United States with a combined capital and surplus of
at least $100,000,000. Upon the acceptance of any appointment as Paying Agent
hereunder by a successor Paying Agent, such successor Paying Agent shall enter
into such documents as the Escrow Agent shall require and shall thereupon
succeed to and become vested with all the rights, powers, privileges and duties
of the retiring Paying Agent, and the retiring Paying Agent shall be discharged
from its duties and obligations hereunder.

            Section 2.06. Notice of Final Withdrawal. Promptly after receipt by
the Paying Agent of notice that the Escrow Agent has requested a Final
Withdrawal or that a Final Withdrawal will be made, the Paying Agent shall cause
notice of the distribution of the Final Withdrawal to be mailed to each of the
Receiptholders at its address as it appears in the Register. Such notice shall
be mailed not less than 15 days prior to the Final Withdrawal Date. Such notice
shall set forth:

            (i) the Final Withdrawal Date and the date for determining
      Receiptholders of record who shall be entitled to receive distributions in
      respect of the Final Withdrawal,

            (ii) the amount of the payment in respect of the Final Withdrawal
      for each $1,000 face amount Certificate (based on information provided by
      the Pass Through Trustee) and the amount thereof constituting unused
      Deposits (as defined in the Deposit Agreement) and interest thereon, and

            (iii) if the Final Withdrawal Date is the same date as a Regular
      Distribution Date, the total amount to be received on such date for each
      $1,000
<PAGE>   15
                                                                              12


      face amount Certificate (based on information provided by the Pass Through
      Trustee).

            Such mailing may include any notice required to be given to
Certificateholders in connection with such distribution pursuant to the Pass
Through Trust Agreement.

            SECTION 3. Payments. If, notwithstanding the instructions in Section
4 of the Deposit Agreement that all amounts payable to the Escrow Agent under
the Deposit Agreement be paid by the Depositary directly to the Paying Agent or
the Pass Through Trustee (depending on the circumstances), the Escrow Agent
receives any payment thereunder, then the Escrow Agent shall forthwith pay such
amount in Dollars and in immediately available funds by wire transfer to (a) in
the case of a payment of accrued interest on the Deposits (as defined in the
Deposit Agreement) or any Final Withdrawal, directly to the Paying Agent Account
and (b) in the case of any Purchase Withdrawal, directly to the Pass Through
Trustee or its designee as specified and in the manner provided in the
Applicable Notice of Purchase Withdrawal. The Escrow Agent hereby waives any and
all rights of set-off, combination of accounts, right of retention or similar
right (whether arising under applicable law, contract or otherwise) it may have
against amounts payable to the Paying Agent howsoever arising.

            SECTION 4. Other Actions. The Escrow Agent shall take such other
actions under or in respect of the Deposit Agreement (including, without
limitation, the enforcement of the obligations of the Depositary thereunder) as
the Investors, by an Action of Investors, may from time to time request.

            SECTION 5.  Representations and Warranties of the Escrow Agent.
The Escrow Agent represents and warrants to America West, the Investors, the
Paying Agent and the Pass Through Trustee as follows:

            (i) it is a banking corporation duly organized and validly existing
      in good standing under the laws of the State of Delaware;

            (ii) it has full power, authority and legal right to conduct its
      business and operations as currently conducted and to enter into and
      perform its obligations under this Agreement and the Deposit Agreement;
<PAGE>   16
                                                                              13


            (iii) the execution, delivery and performance of each of this
      Agreement and the Deposit Agreement have been duly authorized by all
      necessary corporate action on the part of it and do not require any
      stockholder approval, or approval or consent of any trustee or holder of
      any indebtedness or obligations of it, and each such document has been
      duly executed and delivered by it and constitutes its legal, valid and
      binding obligations enforceable against it in accordance with the terms
      hereof or thereof except as such enforceability may be limited by
      bankruptcy, insolvency, moratorium, reorganization or other similar laws
      or equitable principles of general application to or affecting the
      enforcement of creditors' rights generally (regardless of whether such
      enforceability is considered in a proceeding in equity or at law);

            (iv) no authorization, consent or approval of or other action by,
      and no notice to or filing with, any United States federal or state
      governmental authority or regulatory body is required for the execution,
      delivery or performance by it of this Agreement or the Deposit Agreement;

            (v) neither the execution, delivery or performance by it of this
      Agreement or the Deposit Agreement, nor compliance with the terms and
      provisions hereof or thereof, conflicts or will conflict with or results
      or will result in a breach or violation of any of the terms, conditions or
      provisions of, or will require any consent or approval under, any law,
      governmental rule or regulation or the charter documents, as amended, or
      bylaws, as amended, of it or any similar instrument binding on it or any
      order, writ, injunction or decree of any court or governmental authority
      against it or by which it or any of its properties is bound or any
      indenture, mortgage or contract or other agreement or instrument to which
      it is a party or by which it or any of its properties is bound, or
      constitutes or will constitute a default thereunder or results or will
      result in the imposition of any lien upon any of its properties; and
<PAGE>   17
                                                                              14


            (vi) there are no pending or, to its knowledge, threatened actions,
      suits, investigations or proceedings (whether or not purportedly on behalf
      of it) against or affecting it or any of its property before or by any
      court or administrative agency which, if adversely determined, (A) would
      adversely affect the ability of it to perform its obligations under this
      Agreement or the Deposit Agreement or (B) would call into question or
      challenge the validity of this Agreement or the Deposit Agreement or the
      enforceability hereof or thereof in accordance with the terms hereof or
      thereof, nor is the Escrow Agent in default with respect to any order of
      any court, governmental authority, arbitration board or administrative
      agency so as to adversely affect its ability to perform its obligations
      under this Agreement or the Deposit Agreement.

            SECTION 6. Representations and Warranties of the Paying Agent. The
Paying Agent represents and warrants to America West, the Investors, the Escrow
Agent and the Pass Through Trustee as follows:

            (i) it is a banking corporation duly organized and validly existing
      in good standing under the laws of the State of Delaware;

            (ii) it has full power, authority and legal right to conduct its
      business and operations as currently conducted and to enter into and
      perform its obligations under this Agreement;

            (iii) the execution, delivery and performance of this Agreement has
      been duly authorized by all necessary corporate action on the part of it
      and does not require any stockholder approval, or approval or consent of
      any trustee or holder of any indebtedness or obligations of it, and such
      document has been duly executed and delivered by it and constitutes its
      legal, valid and binding obligations enforceable against it in accordance
      with the terms hereof except as such enforceability may be limited by
      bankruptcy, insolvency, moratorium, reorganization or other similar laws
      or equitable principles of general application to or affecting the
      enforcement of creditors' rights generally (regardless of whether
<PAGE>   18
                                                                              15


      such enforceability is considered in a proceeding in equity or at law);

            (iv) no authorization, consent or approval of or other action by,
      and no notice to or filing with, any United States federal or state
      governmental authority or regulatory body is required for the execution,
      delivery or performance by it of this Agreement;

            (v) neither the execution, delivery or performance by it of this
      Agreement, nor compliance with the terms and provisions hereof, conflicts
      or will conflict with or results or will result in a breach or violation
      of any of the terms, conditions or provisions of, or will require any
      consent or approval under, any law, governmental rule or regulation or the
      charter documents, as amended, or bylaws, as amended, of it or any similar
      instrument binding on it or any order, writ, injunction or decree of any
      court or governmental authority against it or by which it or any of its
      properties is bound or any indenture, mortgage or contract or other
      agreement or instrument to which it is a party or by which it or any of
      its properties is bound, or constitutes or will constitute a default
      thereunder or results or will result in the imposition of any lien upon
      any of its properties; and

            (vi) there are no pending or, to its knowledge, threatened actions,
      suits, investigations or proceedings (whether or not purportedly on behalf
      of it) against or affecting it or any of its property before or by any
      court or administrative agency which, if adversely determined, (A) would
      adversely affect the ability of it to perform its obligations under this
      Agreement or (B) would call into question or challenge the validity of
      this Agreement or the enforceability hereof in accordance with the terms
      hereof, nor is the Paying Agent in default with respect to any order of
      any court, governmental authority, arbitration board or administrative
      agency so as to adversely affect its ability to perform its obligations
      under this Agreement.

            SECTION 7. Indemnification. Except for actions expressly required of
the Escrow Agent or the Paying Agent hereunder, each of the Escrow Agent and the
Paying Agent shall
<PAGE>   19
                                                                              16


in all cases be fully justified in failing or refusing to act hereunder unless
it shall have been indemnified (both in such capacities and individually) by the
party requesting such action in a manner reasonably satisfactory to it against
any and all liability and expense which may be incurred by it by reason of
taking or continuing to take any such action. In the event America West requests
any amendment to any Operative Agreement (as defined in the Note Purchase
Agreement), the Pass Through Trustee agrees to pay all reasonable fees and
expenses (including, without limitation, fees and disbursements of counsel) of
the Escrow Agent and the Paying Agent in connection therewith.

            SECTION 8. Amendment, Etc. Upon request of the Pass Through Trustee
and approval by an Action of Investors, the Escrow Agent shall enter into an
amendment to this Agreement, so long as such amendment does not adversely affect
the rights or obligations of the Escrow Agent or the Paying Agent, provided that
upon request of the Pass Through Trustee and without any consent of the
Investors, the Escrow Agent shall enter into an amendment to this Agreement for
any of the following purposes:

            (1) to correct or supplement any provision in this Agreement which
      may be defective or inconsistent with any other provision herein or to
      cure any ambiguity or correct any mistake or to modify any other provision
      with respect to matters or questions arising under this Agreement,
      provided that any such action shall not materially adversely affect the
      interests of the Investors; or

            (2) to comply with any requirement of the SEC, applicable law, rules
      or regulations of any exchange or quotation system on which the
      Certificates are listed or any regulatory body or the Registration Rights
      Agreement to effectuate the Exchange Offer; or

            (3) to evidence and provide for the acceptance of appointment under
      this Agreement of a successor Escrow Agent, successor Paying Agent or
      successor Pass Through Trustee.

            SECTION 9. Notices. Unless otherwise expressly provided herein, any
notice or other communication under this Agreement shall be in writing
(including by facsimile) and shall be deemed to be given and effective upon
receipt thereof (or, if received outside of business hours, on the next open of
business
<PAGE>   20
                                                                              17


on a Business Day). All notices shall be sent to (a) in the case of the
Investors, as their respective addresses shall appear in the Register, (b) in
the case of the Escrow Agent, Wilmington Trust Company, 1100 North Market
Street, Wilmington, Delaware 19890, Attention: Corporate Trust Administration
(Telecopier: 302-651-8882), (c) in the case of the Pass Through Trustee,
Wilmington Trust Company, 1100 North Market Street, Wilmington, Delaware 19890,
Attention: Corporate Trust Administration (Telecopier: 302-651-8882), or (d) in
the case of the Paying Agent, Wilmington Trust Company, 1100 North Market
Street, Wilmington, Delaware 19890, Attention: Corporate Trust Administration
(Telecopier: 302-651-8882), in each case with a copy to America West, America
West Airlines, Inc., 4000 East Sky Harbor Boulevard, Phoenix, Arizona 95043,
Attention: Vice President - Treasurer (Telecopier: (602) 693-5886) (or at such
other address as any such party may specify from time to time in a written
notice to the other parties). On or prior to the execution of this Agreement,
the Pass Through Trustee has delivered to the Escrow Agent a certificate
containing specimen signatures of the representatives of the Pass Through
Trustee who are authorized to give notices and instructions with respect to this
Agreement. The Escrow Agent may conclusively rely on such certificate until the
Escrow Agent receives written notice from the Pass Through Trustee to the
contrary.

            SECTION 10. Transfer. No party hereto shall be entitled to assign or
otherwise transfer this Agreement (or any interest herein) other than (in the
case of the Escrow Agent) to a successor escrow agent under Section 1.06 hereof
or (in the case of the Paying Agent) to a successor paying agent under Section
2.04 hereof, and any purported assignment in violation thereof shall be void.
This Agreement shall be binding upon the parties hereto and their respective
successors and (in the case of the Escrow Agent and the Paying Agent) their
respective permitted assigns. Upon the occurrence of the Transfer (as defined
below) contemplated by the Assignment and Assumption Agreement (as defined
below), the Pass Through Trustee shall (without further act) be deemed to have
transferred all of its right, title and interest in and to this Agreement to the
trustee of the Successor Trust (as defined below) and, thereafter, the trustee
of the Successor Trust shall be deemed to be the "Pass Through Trustee"
hereunder with the rights and obligations of the "Pass Through Trustee"
hereunder and each reference herein to "America West Airlines Pass Through Trust
"1998-1A-O" shall be deemed to be a reference to "America West Airlines Pass
Through Trust 1998-1A-S". The parties hereto
<PAGE>   21
                                       18


hereby acknowledge and consent to the Transfer contemplated by the Assignment
and Assumption Agreement. As used herein, "Transfer" means the transfers of the
assets to the Successor Trust contemplated by the Assignment and Assumption
Agreement; "Assignment and Assumption Agreement" means the Assignment and
Assumption Agreement to be entered into between the Pass Through Trustee and the
trustee of the Successor Trust, substantially in the form of Exhibit D to the
Pass Through Trust Agreement; "Successor Trust" means the America West Airlines
Pass Through Trust 1998-1A-S.

            SECTION 11. Entire Agreement. This Agreement sets forth all of the
promises, covenants, agreements, conditions and understandings among the Escrow
Agent, the Paying Agent, the Initial Purchasers and the Pass Through Trustee
with respect to the subject matter hereof, and supersedes all prior and
contemporaneous agreements and undertakings, inducements or conditions, express
or implied, oral or written.

            SECTION 12. Governing Law.  This Agreement shall be governed by,
and construed in accordance with, the law of the State of New York.

            SECTION 13. Waiver of Jury Trial Right. EACH OF THE ESCROW AGENT,
THE PAYING AGENT, THE INVESTORS AND THE PASS THROUGH TRUSTEE ACKNOWLEDGES AND
ACCEPTS THAT IN ANY SUIT, ACTION OR PROCEEDING ARISING OUT OF OR RELATING TO
THIS AGREEMENT SUCH PARTY IRREVOCABLY WAIVES ITS RIGHT TO A TRIAL BY JURY.

            SECTION 14. Counterparts.  This Agreement may be executed in one
or more counterparts, all of which taken together shall constitute one
instrument.
<PAGE>   22
                                       19


            IN WITNESS WHEREOF, the Escrow Agent, the Paying Agent, the Initial
Purchasers and the Pass Through Trustee have caused this Escrow and Paying Agent
Agreement (Class A) to be duly executed as of the day and year first above
written.

                                    WILMINGTON TRUST COMPANY, as Escrow Agent

                                   
                                    By /s/ Norma P. Closs
                                       --------------------------------
                                     Name: Norma P. Closs
                                       Title: Vice President


                                    MORGAN STANLEY & CO. INCORPORATED,
                                    DONALDSON, LUFKIN & JENRETTE SECURITIES
                                    CORPORATION,
                                    MERRILL LYNCH, PIERCE, FENNER & SMITH
                                    INCORPORATED and
                                    SALOMON SMITH BARNEY INC.,
                                       as Initial Purchasers


                                    By: MORGAN STANLEY & CO.
                                         INCORPORATED


                                    By /s/ Tom Cahill
                                       --------------------------------
                                       Name: Tom Cahill
                                       Title:

                                    WILMINGTON TRUST COMPANY, not in its
                                    individual capacity, but solely as Pass
                                    Through Trustee for and on behalf of America
                                    West Airlines Pass Through Trust
                                    1998-1A-O


                                    By /s/ James P. Lawler
                                       ----------------------------------
                                       Name: James P. Lawler
                                       Title: Vice President
<PAGE>   23
                                                                              20


                                    WILMINGTON TRUST COMPANY,
                                    as Paying Agent


                                    By /s/ Norma P. Closs
                                       ------------------------
                                       Name: Norma P. Closs
                                       Title: Vice President
<PAGE>   24
                                                                              


                                                                       EXHIBIT A

                  AMERICA WEST AIRLINES 1998-1A ESCROW RECEIPT

                                     No. __

            This Escrow Receipt evidences a fractional undivided interest in
amounts ("Account Amounts") from time to time deposited into a certain paying
agent account (the "Paying Agent Account") described in the Escrow and Paying
Agent Agreement (Class A) dated as of October 6, 1998 (as amended, modified or
supplemented from time to time, the "Escrow and Paying Agent Agreement") among
Wilmington Trust Company, as Escrow Agent (in such capacity, together with its
successors in such capacity, the "Escrow Agent"), Morgan Stanley & Co.
Incorporated, Donaldson, Lufkin & Jenrette Securities Corporation , Merrill
Lynch, Pierce, Fenner & Smith Incorporated and Salomon Smith Barney Inc., as
Initial Purchasers, Wilmington Trust Company, as Pass Through Trustee (in such
capacity, together with its successors in such capacity, the "Pass Through
Trustee") and Wilmington Trust Company, as paying agent (in such capacity,
together with its successors in such capacity, the "Paying Agent"). Capitalized
terms not defined herein shall have the meanings assigned to them in the Escrow
and Paying Agent Agreement.

            This Escrow Receipt is issued under and is subject to the terms,
provisions and conditions of the Escrow and Paying Agent Agreement. By virtue of
its acceptance hereof the holder of this Escrow Receipt assents and agrees to be
bound by the provisions of the Escrow and Paying Agent Agreement and this Escrow
Receipt.

            This Escrow Receipt represents a fractional undivided interest in
amounts deposited from time to time in the Paying Agent Account, and grants or
represents no rights, benefits or interests of any kind in respect of any assets
or property other than such amounts. This Escrow Receipt evidences the same
percentage interest in the Account Amounts as the Fractional Undivided Interest
in the Pass Through Trust evidenced by the Certificate to which this Escrow
Receipt is affixed.

            All payments and distributions made to Receiptholders in respect of
the Escrow Receipt shall be made only from Account Amounts deposited in the
Paying Agent Account. The holder of this Escrow Receipt, by its acceptance of
this Escrow Receipt, agrees that it will look solely to the Account Amounts for
any payment or distribution due to it pursuant to this Escrow
<PAGE>   25
                                                                               2


Receipt and that it will not have any recourse to America West, the Pass Through
Trustee, the Paying Agent or the Escrow Agent, except as expressly provided
herein or in the Pass Through Trust Agreement. No Receiptholder of this Escrow
Receipt shall have any right to vote or in any manner otherwise control the
operation and management of the Paying Agent Account, nor shall anything set
forth herein, or contained in the terms of this Escrow Receipt, be construed so
as to constitute the Receiptholders from time to time as partners or members of
an association.

            This Escrow Receipt may not be assigned or transferred except in
connection with the assignment or transfer of the Certificate to which this
Escrow Receipt is affixed. After payment to the holder hereof of its Escrow
Interest in the Final Distribution, upon the request of the Pass Through
Trustee, the holder hereof will return this Escrow Receipt to the Pass Through
Trustee.

            The Paying Agent may treat the person in whose name the Certificate
to which this Escrow Receipt is attached as the owner hereof for all purposes,
and the Paying Agent shall not be affected by any notice to the contrary.

            THIS ESCROW RECEIPT SHALL BE GOVERNED BY AND CONSTRUED IN ACCORDANCE
WITH THE LAW OF THE STATE OF NEW YORK.

            IN WITNESS WHEREOF, the Escrow Agent has caused this Escrow Receipt
to be duly executed.

Dated: ______________, 199_

                                    WILMINGTON TRUST COMPANY,
                                    as Escrow Agent

                                    By __________________________
                                       Name:
                                       Title:
<PAGE>   26
                                                                       EXHIBIT B

                             WITHDRAWAL CERTIFICATE
                                    (Class A)

                            WILMINGTON TRUST COMPANY,
                                 as Escrow Agent

Dear Sirs:

            Reference is made to the Escrow and Paying Agent Agreement, dated as
of October 6, 1998 (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 (312)
606-8428, Attention: Vice President - Aerospace.


                                    Very truly yours,

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


                                    By __________________________
                                       Name:
                                       Title:



Dated:  ____________, 199_