<PAGE>
 
                                                                 EXHIBIT 10.8(a)
 
                          Acknowledgement and Consent
                          ---------------------------

Acknowledgement and Consent (this "Consent") of Frontier Airlines, Inc. dated as
of March 28, 1997.

Recitals: US Airways, Inc., (formerly USAir, Inc., "US Airways"), as lessor and
--------
Frontier Airlines, Inc. ("Lessee"), as lessee, entered into that certain Lease
Agreement dated as of July 26, 1994 (the "Lease") whereby US Airways agreed to
lease to Lessee and Lessee agreed to lease from US Airways the Boeing 737-201
Airframe and the Engines identified in the Assignment (defined below).  US
Airways and First Security Bank, National Association, not in its individual
capacity but solely as Owner Trustee ("Trustee"), as trustee for the S-C
Parties, have entered into an Assignment and Assumption Agreement (the
"Assignment") dated as of March 28, 1997, whereby US Airways has assigned to the
Trustee all of the right, title and interest of US Airways in and to the
Assigned Documents and the Aircraft.  The Trustee desires that Lessee
acknowledge and consent to the Assignment and reaffirm its representations,
warranties and obligations to the Trustee.

     Accordingly, the Trustee and Lessee agree as follows:

1.   Defined Terms.  Unless otherwise defined herein or the context requires
     -------------
     otherwise, all capitalized terms used herein shall have the meanings
     assigned to them in the Assignment.

2.   Acknowledgement and Consent.  Lessee hereby acknowledges and consents to
     ---------------------------
     the Assignment (a copy of which is attached hereto as Exhibit "A"), and all
     of the terms and conditions contained therein.

3.   Representations, Warranties and Obligations.  All representations and
     -------------------------------------------
     warranties of Lessee in the Assigned Documents were true and correct when
     made and, on the Closing Date, will be true and correct.  Lessee further
     affirms its liability to the Trustee for all of its obligations and duties
     under the Assigned Documents.  In reliance upon US Airways' agreement to be
     responsible therefor and US Airways' performance thereof, Lessee
     acknowledges and agrees that Trustee shall not be bound by or subject to
     any of the duties obligating or responsibilities described in Section 4 of
     the Assignment.
<PAGE>
 
                                                                     PAGE 2 OF 4

4.   Notices.  Pursuant to Section 19.2 of the Lease and Section 7.5 of the
     -------
     Supplementary Agreement, all requests, notices and other communications to
     the "Lessor" shall, from the date of this Consent, be addressed to the
     Trustee, as follows (or to such other address as the Trustee shall specify
     from time to time):

                    First Security Bank, National Association
                    Corporate Trust Department
                    79 South Main Street - 3rd Floor
                    Salt Lake City, Utah 84111
                    Attention: Corporate Trust Administration

                    with copies to:

                    Soros Fund Management LLC
                    888 Seventh Avenue
                    New York, New York 10106
                    Attention: Michael C. Neus
                    Facsimile: 212-664-0544

                    and

                    S-C Domestic Holdings VII LLC
                    c/o Curacao Corporation Company N.V.
                    Kaya Flamboyan 9
                    Willemstad, Curacao N.A.
                    Attention: Ben Jansen
                    Facsimile: 5999 32 20 01
 
                    and
 
                    C-S Aviation Services, Inc.
                    888 Seventh Avenue, Suite 2901
                    New York, New York 10106
                    Attention: Thomas Seery
                    Facsimile: 212-246-0102

5.   Payments.  All payments other than Hourly Rent to be made to "Lessor" under
     --------
     the Assigned Documents shall, from the date of this Consent, be made to the
     following bank account (or to such other account as the Trustee shall
     specify from time to time):
 
                    Citibank New York
                    ABA No.: 021 0000 89
                    Account Name: For further credit to                
                         Citibank London
                    Account No. 10990765
                    Account Name: S-C Domestic Holdings II LLC
                    Account No. 8228825
<PAGE>
 
                                                                     PAGE 3 OF 4


        All payments of Hourly Rent to be made to "Lessor" under the Assigned
     Documents shall, from the date of this Consent, be made to the following
     bank account (or such other account as the Trustee shall specify from time
     to time):

                    Citibank New York
                    ABA No.: 021 000 089
                    Account Name: For further credit
                    to Citibank London
                    Account No.: 10990765
                    Account Name: S-C Aircraft Holdings LLC
                    Account No.: 8300631
 
6.   Insurance.  Lessee will cooperate in having the Trustee, the S-C Parties
     ---------
     and US Airways named as additional insureds under the liability insurance,
     and the Trustee named as sole loss payee under the hull insurance procured
     by Lessee under the Lease.

7.   Miscellaneous.  This Consent may be executed by the parties hereto in
     -------------
     separate counterparts, each fully executed set of which when so executed
     and delivered shall be an original, but all such counterparts shall
     together constitute but one and the same instrument. This Consent shall be
     governed by the laws of the State of New York.  The respective rights and
     obligations set forth in this Consent shall be binding on and inure to the
     benefit of the parties hereto and their respective successors and assigns.
<PAGE>
 
                                                                     PAGE 4 OF 4


     The undersigned has executed this Acknowledgement and Consent.


                                                 Frontier Airlines, Inc.

                                                 By: ___________________________

                                                 Title: ________________________


Agreed:

First Security Bank, National
  Association, as Trustee

By: ___________________________

Title: ________________________
<PAGE>
 
                                                                     EXHIBIT "A"


                      ASSIGNMENT AND ASSUMPTION AGREEMENT
                      -----------------------------------

     ASSIGNMENT AND ASSUMPTION AGREEMENT (this "Assignment"), dated as of March
28, 1997, by and between US Airways, Inc. ("US Airways"), a Delaware
corporation, formerly known as USAir, Inc., and FIRST SECURITY BANK, NATIONAL
ASSOCIATION, a national banking association, not in its individual capacity but
solely as Owner Trustee ("Trustee").

                                   RECITALS:
                                   --------

     US Airways and Trustee desire to effect (a) the transfer by US Airways to
Trustee of all of the right, title and interest of US Airways (except as
excluded in Section 4 below) in, under and with respect to, among other things,
(i) the Aircraft Lease Agreement (as supplemented by the Lease Supplement
defined below and to the extent relating to the Aircraft, the "Lease"), dated as
of July 26, 1994, between US Airways and Frontier Airlines, Inc. (the,
"Lessee"), as supplemented by Lease Supplement No. 4, dated September 9, 1994
(the "Lease Supplement"), (ii) Supplementary Agreement, dated as of June 6, 1994
between US Airways and Lessee, as it relates to the Aircraft (defined below),
(iii) all certificates, opinions, and other documents relating to the Operative
Document as they relate to the Boeing 737-201 airframe with manufacturer's
serial number 19421 and United States Registration Number N205AU and the Pratt &
Whitney model JT8D-9A aircraft engines (which engines have 750 or more rated
takeoff horsepower or the equivalent) with manufacturer's serial numbers 654736
and 667183 (such airframe and the engines (as further defined in the Lease), the
"Aircraft") (all of the foregoing collectively, the "Assigned Documents"), (iv)
the Aircraft, (v) the Hourly Rent Balances and the security deposits of Lessee
as they relate to the Aircraft (collectively, the "Assigned Accounts"), and (vi)
the proceeds from all of the foregoing; and (b) the assumption by Trustee of the
obligations of US Airways (except as excluded in Section 4 below) to the extent
arising after the Effective Date under the Assigned Documents.  The Lease was
recorded by the Federal Aviation Administration on August 22, 1994 and assigned
Conveyance No. EE007565.  The Lease Supplement was recorded by the Federal
Aviation Administration on November 7, 1994 and assigned Conveyance No. LL08354.

     NOW, THEREFORE, in consideration of the mutual agreements contained herein,
it is hereby agreed as follows:

     1.  Definitions.  Capitalized terms used herein without definition shall 
         -----------
have meaning ascribed thereto in the Lease unless the context in which such term
is used requires another meaning.
<PAGE>
 
     2.  Assignment.  US Airways does hereby sell, convey, assign, transfer and
         ----------
set over to Trustee, effective as of the date first above written (the
"Effective Date"), all of its right, title and interest in, under and to the
Assigned Documents, the Assigned Accounts and all other contracts, agreements,
documents or instruments in respect of the aircraft to which US Airways is a
party and relating to the Operative Agreements or the Aircraft and any proceeds
therefrom, together with all other documents and instruments evidencing any of
such right, title and interest.

     3.  Assumption.  Trustee hereby undertakes and assumes all of the duties 
         ----------
and obligations of US Airways relating to the period after the Effective Date
pursuant to the Assigned Documents and any other contracts, agreements,
documents or instruments relating thereto to which US Airways is a party or by
which it is bound, and hereby confirms that it shall be deemed a party to and be
bound by the Assigned Documents and each other contract, agreement, document or
instrument in respect of the Aircraft relating thereto to which US Airways is a
party or by which it is bound as if named therein as "Lessor".

     4.  Excluded Obligations.  Notwithstanding anything to the contrary set 
         --------------------
forth in this Assignment, US Airways is not assigning to Trustee and US Airways
shall remain responsible for, and Trustee is not assuming from US Airways: (a)
the duties and obligations described on Schedule A, (b) the duties and
obligations of US Airways that relate to any period on or prior to the Effective
Date, (c) any other duties and obligations of US Airways relating to parts or
engine consignments, spare parts or spare engines, and (d) without limiting the
foregoing, the right of US Airways to receive any Rent due or accrued to US
Airways prior to the Effective Date and any indemnity relating to events
occurring prior to the Effective Date.

     5.  Release of US Airways. Except for obligations not assumed as provided
         ---------------------
in Section 4 hereof and for which US Airways shall remain responsible, US
Airways shall have no further duty or obligation to Lessee under the Assigned
Documents, the Assigned Accounts or under any other contract, agreement,
document or other instrument relating thereto to which US Airways is a party or
by which it is bound (other than this Agreement).

     6.  Further Assignment.  In furtherance of the within assignments, US 
         ------------------
Airways assigns and grants to Trustee all right to collect for the account of
Trustee all items sold, transferred or assigned to Trustee pursuant hereto; to
institute and prosecute all proceedings that Trustee may deem proper in order to
collect, assert or enforce any claim, right or title of any kind in or to the
items sold, transferred or assigned; to defend and compromise any and all
actions, suits or proceedings as to 
<PAGE>
 
title to or interest in the Aircraft or any of the property acquired by Trustee;
and to do all such acts and things in relating thereto as Trustee shall deem
advisable.

     7.  Payments.  US Airways hereby covenants and agrees to pay over to 
         --------
Trustee, if and when received following the Effective Date, any amounts
(including any sums payable as interest in respect thereof) paid to or for the
benefit of US Airways that, under Section 2 hereof, belong to Trustee, and
Trustee hereby covenants and agrees to pay over to US Airways, if and when
received following the Effective Date, any amounts (including any sums payable
as interest in respect thereof) paid to or for the benefit of Trustee that,
under Section 2 hereof, belong to US Airways.

     8.  Further Assurances.  Each party to this Assignment and Assumption 
         ------------------
Agreement agrees to execute, acknowledge, deliver, file, record and publish such
further certificates, amendments, instruments or documents, and to do all such
further acts and things, as may be required by law, or as may reasonably be
necessary or advisable to carry out the intents and purposes of this Assignment
and Assumption Agreement.

     9.  Expenses.  Each party hereto shall bear its own legal fees incurred in
         --------
connection with the transactions described herein.

    10.  Governing Law.  This Assignment and Assumption Agreement shall be 
         -------------
governed by and construed in accordance with the laws of the State of New York.

    11.  Headings.  Section headings used in this Assignment are for convenience
         --------
only and shall not be used in interpreting or construing this Assignment and
Assumption Agreement and shall not affect the meaning or construction of this
Assignment and Assumption Agreement.

    12.  Notices.  All notices and other communications hereunder shall be in
         -------
writing and shall be deemed given if delivered to the parties at the following
addresses (or at such other address for a party as shall be specified by like
notice):

     a.  If to US Airways:
         ----------------
         US Airways, Inc.
         2345 Crystal Drive
         Arlington, Virginia 22227
         Attention: Director - Aircraft Sales
         Facsimile: 703-418-7515

         with a copy at the same address to the attention of US Airways'
         General Counsel, facsimile number (703) 418-5252
<PAGE>
 
     b.  If to Trustee:
         -------------
         First Security Bank, National Association
         79 South Main Street, 3rd Floor
         Salt Lake City, Utah 84111
         Attention: Corporate Trust Administration
         Facsimile: 801-246-5053

    13.  Entire Agreement.  This Assignment constitutes the entire agreement 
         ----------------
among the parties hereto and supersedes all prior agreements and understandings,
both written and oral, with respect to the subject matter hereof. There are no
representations and warranties of any party hereto except as expressly set forth
herein.

    14.  Survival of Representations and Warranties.  All representations and
         ------------------------------------------
warranties contained in this Assignment shall survive the Effective Date.

    15.  Counterparts.  This Assignment may be executed by the parties hereto in
         ------------
separate counterparts, each of which when so executed and delivered shall be an
original, but all such counterparts shall together constitute but one and the
same instrument.

    16.  Successors and Assigns.  The respective rights and obligations set 
         ----------------------
forth in this Assignment shall be binding on and inure to the benefit of the
parties hereto and their respective successors and assigns.

                 [remainder of page left blank intentionally]
<PAGE>
 
     IN WITNESS WHEREOF, the parties hereto have duly executed this Assignment
and Assumption Agreement as of the day and year set forth above.


                                                US AIRWAYS, INC.

                                                BY: ____________________________
 
                                                NAME: __________________________

                                                TITLE: _________________________

                                                DATED: _________________________


                                                FIRST SECURITY BANK, NATIONAL
                                             ASSOCIATION, AS OWNER TRUSTEE
 
                                                BY: ____________________________
 
                                                NAME: __________________________

                                                TITLE: _________________________

                                                DATED: _________________________
<PAGE>
 
                                                                      SCHEDULE A


                             Excluded Obligations
                             --------------------

     (a)  (S)2.6 of the Supplementary Agreement (license of maintenance and
          weight and balance programs)

     (b)  (S)4.2(f) of the Supplementary Agreement (US Airways' representations)

     (c)  (S)5.2(f) of the Supplementary Agreement (sub-clause (i), second
          sentence (hushkit procurement assistance); sub-clause (ii) first,
          second and third sentences (DFDR Program))

     (d)  (S)5.3 of the Supplementary Agreement (spare parts consignment)

     (e)  (S)5.4 of the Supplementary Agreement (US Airways-provided maintenance
          work)

     (f)  Without limiting the applicability or scope of the foregoing, all
          obligations of US Airways to Lessee arising under the Assigned
          Documents which shall have arisen or occurred on or before the date
          set forth in the introductory paragraph of this Assignment.

EACH OF THE FOREGOING EXCLUDED OBLIGATIONS DESCRIBED IN PARAGRAPHS (A) - (E)
SHALL REMAIN THE OBLIGATIONS OF US AIRWAYS DURING THE BASE LEASE TERM AND ANY
RENEWAL TERM.
<PAGE>
 
                          Acknowledgement and Consent
                          ---------------------------

Acknowledgement and Consent (this "Consent") of Frontier Airlines, Inc. dated as
of March 28, 1997.

Recitals: US Airways, Inc., (formerly USAir, Inc., "US Airways"), as lessor and
--------
Frontier Airlines, Inc. ("Lessee"), as lessee, entered into that certain Lease
Agreement dated as of July 26, 1994 (the "Lease") whereby US Airways agreed to
lease to Lessee and Lessee agreed to lease from US Airways the Boeing 737-201
Airframe and the Engines  identified in the Assignment (defined below).  US
Airways and First Security Bank, National Association, not in its individual
capacity but soley as Owner Trustee ("Trustee"), as trustee for the S-C Parties,
have entered into an Assignment and Assumption Agreement (the "Assignment")
dated as of March 28, 1997, whereby US Airways has assigned to the Trustee all
of the right, title and interest of US Airways in and to the Assigned Documents
and the Aircraft.  The Trustee desires that Lessee acknowledge and consent to
the Assignment and reaffirm its representations, warranties and obligations to
the Trustee.

     Accordingly, the Trustee and Lessee agree as follows:

1.   Defined Terms.  Unless otherwise defined herein or the context requires
     -------------
     otherwise, all capitalized terms used herein shall have the meanings
     assigned to them in the Assignment.

2.   Acknowledgement and Consent.  Lessee hereby acknowledges and consents to
     ---------------------------
     the Assignment (a copy of which is attached hereto as Exhibit "A"), and all
     of the terms and conditions contained therein.

3.   Representations, Warranties and Obligations.  All representations and
     -------------------------------------------
     warranties of Lessee in the Assigned Documents were true and correct when
     made and, on the Closing Date, will be true and correct.  Lessee further
     affirms its liability to the Trustee for all of its obligations and duties
     under the Assigned Documents.  In reliance upon US Airways' agreement to be
     responsible therefor and US Airways' performance thereof, Lessee
     acknowledges and agrees that Trustee shall not be bound by or subject to
     any of the duties obligating or responsibilities described in Section 4 of
     the Assignment.
<PAGE>
 
                                                            PAGE 2 OF 4

4.   Notices.  Pursuant to Section 19.2 of the Lease and Section 7.5 of the
     -------
     Supplementary Agreement, all requests, notices and other communications to
     the "Lessor" shall, from the date of this Consent, be addressed to the
     Trustee, as follows (or to such other address as the Trustee shall specify
     from time to time):

                First Security Bank, National Asssociation          
                Corporate Trust Department                          
                79 South Main Street - 3rd Floor                    
                Salt Lake City, Utah 84111                          
                Attention: Corporate Trust Administration           
                                                                    
                with copies to:                                     
                                                                    
                S-C Domestic Holdings VII LLC                       
                c/o Curacao Corporation Company N.V.                
                Kaya Flamboyan 9                                    
                Willemstad, Curacao N.A.                            
                Attention: Ben Jansen                               
                Facsimile: 5999 32 20 01                            
                                                                    
                and                                                 
                                                                    
                Soros Fund Managment LLC                            
                888 Seventh Avenue                                  
                New York, New York 10106                            
                Attention: Michael C. Neus                          
                Facsimile: 212-664-0544                             
                                                                    
                and                                                 
                                                                    
                C-S Aviation Services, Inc.                         
                888 Seventh Avenue, Suite 2901                      
                New York, New York 10106                            
                Attention: Thomas Seery                             
                Facsimile: 212-246-0102                              


5.   Payments.  All payments other than Hourly Rent to be made to "Lessor" under
     --------
     the Assigned Documents shall, from the date of this Consent, be made to the
     following bank account (or to such other account as the Trustee shall
     specify from time to time):
 
                Citibank New York
                ABA No.:        021000089
                Account Name:   Further Credit to             
                                Citibank London
                Account No.:    10990765
                Account Name:   S-C Domestic Holdings II LLC
                Account No.:    8228825
<PAGE>
 
                                                            PAGE 3 OF 4


        All payments of Hourly Rent to be made to "Lessor" under the Assigned
     Documents shall, from the date of this Consent, be made to the following
     bank account (or such other account as the Trustee shall specify from time
     to time):

                Citibank New York
                ABA No.:      021 000 089
                Account Name: For further credit
                              to Citibank London
                Account No.:  10990765
                Account Name: S-C Aircraft Holdings LLC
                Account No.:  8300631
 
6.   Insurance.  Lessee will cooperate in having the Trustee, the S-C Parties
     ---------
     and US Airways named as additional insureds under the liability insurance,
     and the Trustee named as sole loss payee under the hull insurance procured
     by Lessee under the Lease.

7.   Miscellaneous.  This Consent may be executed by the parties hereto in
     -------------
     separate counterparts, each fully executed set of which when so executed
     and delivered shall be an original, but all such counterparts shall
     together constitute but one and the same instrument. This Consent shall be
     governed by the laws of the State of New York.  The respective rights and
     obligations set forth in this Consent shall be binding on and inure to the
     benefit of the parties hereto and their respective successors and assigns.
<PAGE>
 
                                                            PAGE 4 OF 4


     The undersigned has executed this Acknowledgement and Consent.


                        Frontier Airlines, Inc.

                        By: ___________________________

                        Title: ________________________


Agreed:

First Security Bank, National
 Association, as Trustee

By: ___________________________

Title: ________________________
<PAGE>
 
                                                            EXHIBIT "A"

                      ASSIGNMENT AND ASSUMPTION AGREEMENT
                      -----------------------------------

        ASSIGNMENT AND ASSUMPTION AGREEMENT (this "Assignment"), dated as of
March 28, 1997, by and between US Airways, Inc. ("US Airways"), a Delaware
corporation, formerly known as USAir, Inc., and FIRST SECURITY BANK, NATIONAL
ASSOCIATION, a national banking association, not in its individual capacity but
solely as Owner Trustee ("Trustee").

                                 RECITALS:
                                 ---------

        US Airways and Trustee desire to effect (a) the transfer by US Airways
to Trustee of all of the right, title and interest of US Airways (except as
excluded in Section 4 below) in, under and with respect to, among other things,
(i) the Aircraft Lease Agreement (as supplemented by the Lease Supplement
defined below, and to the extent relating to the Aircraft, the "Lease"), dated
as of July 26, 1994, between US Airways and Frontier Airlines, Inc. (the,
"Lessee"), as supplemented by Lease Supplement No. 2, dated July 26, 1994 (the
"Lease Supplement"), (ii) Supplementary Agreement, dated as of June 6, 1994
between US Airways and Lessee, as it relates to the Aircraft (defined below),
(iii) all certificates, opinions, and other documents relating to the Operative
Document as they relate to the Boeing 737-201 airframe with manufacturer's
serial number 19423 and United States Registration Number N207AU and the Pratt &
Whitney model JT8D-9A aircraft engines (which engines have 750 or more rated
takeoff horsepower or the equivalent) with manufacturer's serial numbers 667219
and 667196 (such airframe and the engines (as further defined in the Lease), the
"Aircraft") (all of the foregoing collectively, the "Assigned Documents"), (iv)
the Aircraft, (v) the Hourly Rent Balances and the security deposits of Lessee
as they relate to the Aircraft (collectively, the "Assigned Accounts"), and (vi)
the proceeds from all of the foregoing; and (b) the assumption by Trustee of the
obligations of US Airways (except as excluded in Section 4 below) to the extent
arising after the Effective Date. The Lease was recorded by the Federal Aviation
Administration on August 22, 1994 and assigned Conveyance No. EE007565. The
Lease Supplement was recorded by the Federal Aviation Administration on August
22, 1994 and assigned Conveyance No. EE007565.

        NOW, THEREFORE, in consideration of the mutual agreements contained
herein, it is hereby agreed as follows:

        1.  Definitions.  Capitalized terms used herein without definition shall
            -----------
have meaning ascribed thereto in the Lease unless the context in which such term
is used requires another meaning.
<PAGE>
 
        2. Assignment. US Airways does hereby sell, convey, assign, transfer and
           ----------
set over to Trustee, effective as of the date first above written (the
"Effective Date"), all of its right, title and interest in, under and to the
Assigned Documents, the Assigned Accounts and all other contracts, agreements,
documents or instruments in respect of the aircraft to which US Airways is a
party and relating to the Operative Agreements or the Aircraft and any proceeds
therefrom, together with all other documents and instruments evidencing any of
such right, title and interest.

        3. Assumption. Trustee hereby undertakes and assumes all of the duties
           ----------
and obligations of US Airways relating to the period after the Effective Date
pursuant to the Assigned Documents and any other contracts, agreements,
documents or instruments relating thereto to which US Airways is a party or by
which it is bound, and hereby confirms that it shall be deemed a party to and be
bound by the Assigned Documents and each other contract, agreement, document or
instrument in respect of the Aircraft relating thereto to which US Airways is a
party or by which it is bound as if named therein as "Lessor".

        4. Excluded Obligations. Notwithstanding anything to the contrary set
           --------------------
forth in this Assignment, US Airways is not assigning to Trustee and US Airways
shall remain responsible for, and Trustee is not assuming from US Airways: (a)
the duties and obligations described on Schedule A, (b) the duties and
obligations of US Airways that relate to any period on or prior to the Effective
Date, (c) any other duties and obligations of US Airways relating to parts or
engine consignments, spare parts or spare engines, and (d) without limiting the
foregoing, the right of US Airways to receive any Rent due or accrued to US
Airways prior to the Effective Date and any indemnity relating to events
occurring prior to the Effective Date.
 
        5. Release of US Airways. Except for obligations not assumed as provided
           ---------------------
in Section 4 hereof and for which US Airways shall remain responsible, US
Airways shall have no further duty or obligation to Lessee under the Assigned
Documents, the Assigned Accounts or under any other contract, agreement,
document or other instrument relating thereto to which US Airways is a party or
by which it is bound (other than this Agreement).

        6. Further Assignment. In furtherance of the within assignments, US
           ------------------
Airways assigns and grants to Trustee all right to collect for the account of
Trustee all items sold, transferred or assigned to Trustee pursuant hereto; to
institute and prosecute all proceedings that Trustee may deem proper in order to
collect, assert or enforce any claim, right or title of any kind in or to the
items sold, transferred or assigned; to defend and compromise any and all
actions, suits or proceedings as to
<PAGE>
 
title to or interest in the Aircraft or any of the property acquired by Trustee;
and to do all such acts and things in relating thereto as Trustee shall deem
advisable.

        7.  Payments. US Airways hereby covenants and agrees to pay over to
            --------
Trustee, if and when received following the Effective Date, any amounts
(including any sums payable as interest in respect thereof) paid to or for the
benefit of US Airways that, under Section 2 hereof, belong to Trustee, and
Trustee hereby covenants and agrees to pay over to US Airways, if and when
received following the Effective Date, any amounts (including any sums payable
as interest in respect thereof) paid to or for the benefit of Trustee that,
under Section 2 hereof, belong to US Airways.

        8.  Further Assurances. Each party to this Assignment and Assumption
            ------------------
Agreement agrees to execute, acknowledge, deliver, file, record and publish such
further certificates, amendments, instruments or documents, and to do all such
further acts and things, as may be required by law, or as may reasonably be
necessary or advisable to carry out the intents and purposes of this Assignment
and Assumption Agreement.

        9.  Expenses. Each party hereto shall bear its own legal fees incurred 
            --------
in connection with the transactions described herein.

        10. Governing Law. This Assignment and Assumption Agreement shall be
            -------------
governed by and construed in accordance with the laws of the State of New York.

        11. Headings. Section headings used in this Assignment are for
            --------
convenience only and shall not be used in interpreting or construing this
Assignment and Assumption Agreement and shall not affect the meaning or
construction of this Assignment and Assumption Agreement.

        12. Notices.  All notices and other communications hereunder shall be in
            -------
writing and shall be deemed given if delivered to the parties at the following
addresses (or at such other address for a party as shall be specified by like
notice):

        a.  If to US Airways:
            -----------------
            US Airways, Inc.
            2345 Crystal Drive
            Arlington, Virginia 22227
            Attention: Director - Aircraft Sales
            Facsimile: 703-418-7515

            with a copy at the same address to the attention of US Airways'
            General Counsel, facsimile number (703) 418-5252
<PAGE>
 
         b. If to Trustee:
            --------------
            First Security Bank, National Association
            79 South Main Street, 3rd Floor
            Salt Lake City, Utah 84111
            Attention: Corporate Trust Administration
            Facsimile: 801-246-5053

        13. Entire Agreement. This Assignment constitutes the entire agreement
            ----------------
among the parties hereto and supersedes all prior agreements and understandings,
both written and oral, with respect to the subject matter hereof. There are no
representations and warranties of any party hereto except as expressly set forth
herein.

        14. Survival of Representations and Warranties.  All representations and
            ------------------------------------------
warranties contained in this Assignment shall survive the Effective Date.

        15. Counterparts. This Assignment may be executed by the parties hereto
            ------------
in separate counterparts, each of which when so executed and delivered shall be
an original, but all such counterparts shall together constitute but one and the
same instrument.

        16. Successors and Assigns. The respective rights and obligations set
            ----------------------
forth in this Assignment shall be binding on and inure to the benefit of the
parties hereto and their respective successors and assigns.

                 [remainder of page left blank intentionally]
<PAGE>
 
        IN WITNESS WHEREOF, the parties hereto have duly executed this
Assignment and Assumption Agreement as of the day and year set forth above.


                                US AIRWAYS, INC.

                                BY: ____________________________
 
                                NAME: __________________________

                                TITLE: _________________________

                                DATED: _________________________


                                FIRST SECURITY BANK, NATIONAL               
                                ASSOCIATION, AS OWNER TRUSTEE
 
                                BY: ____________________________
 
                                NAME: __________________________

                                TITLE: _________________________

                                DATED: _________________________
<PAGE>
 
                                                            SCHEDULE A


                             Excluded Obligations
                             ---------------------

     (a)  (S)2.6 of the Supplementary Agreement (license of maintenance and
          weight and balance programs)

     (b)  (S)4.2(f) of the Supplementary Agreement (US Airways' representations)

     (c)  (S)5.2(f) of the Supplementary Agreement (sub-clause (i), second
          sentence (hushkit procurement assistance); sub-clause (ii) first,
          second and third sentences (DFDR Program))

     (d)  (S)5.3 of the Supplementary Agreement (spare parts consignment)

     (e)  (S)5.4 of the Supplementary Agreement (US Airways-provided maintenance
          work)

     (f)  Without limiting the applicability or scope of the foregoing, all
          obligations of US Airways to Lessee arising under the Assigned
          Documents which shall have arisen or occurred on or before the date
          set forth in the introductory paragraph of this Assignment.

EACH OF THE FOREGOING EXCLUDED OBLIGATIONS DESCRIBED IN PARAGRAPHS (A) - (E)
SHALL REMAIN THE OBLIGATIONS OF US AIRWAYS DURING THE BASE LEASE TERM AND ANY
RENEWAL TERM.
<PAGE>
 
                          Acknowledgement and Consent
                          ---------------------------

Acknowledgement and Consent (this "Consent") of Frontier Airlines, Inc. dated as
of March 28, 1997.

Recitals: US Airways, Inc., (formerly USAir, Inc., "US Airways"), as lessor and
--------
Frontier Airlines, Inc. ("Lessee"), as lessee, entered into that certain Lease
Agreement dated as of July 26, 1994 (the "Lease") whereby US Airways agreed to
lease to Lessee and Lessee agreed to lease from US Airways the Boeing 737-201
Airframe and the Engines identified in the Assignment (defined below).  US
Airways and First Security Bank, National Association, not in its individual
capacity but solely as Owner Trustee ("Trustee"), as trustee for the S-C
Parties, have entered into an Assignment and Assumption Agreement (the
"Assignment") dated as of March 28, 1997, whereby US Airways has assigned to the
Trustee all of the right, title and interest of US Airways in and to the
Assigned Documents and the Aircraft.  The Trustee desires that Lessee
acknowledge and consent to the Assignment and reaffirm its representations,
warranties and obligations to the Trustee.


     Accordingly, the Trustee and Lessee agree as follows:

1.   Defined Terms.  Unless otherwise defined herein or the context requires
     -------------
     otherwise, all capitalized terms used herein shall have the meanings
     assigned to them in the Assignment.

2.   Acknowledgement and Consent.  Lessee hereby acknowledges and consents to
     ---------------------------
     the Assignment (a copy of which is attached hereto as Exhibit "A"), and all
     of the terms and conditions contained therein.

3.   Representations, Warranties and Obligations.  All representations and
     -------------------------------------------
     warranties of Lessee in the Assigned Documents were true and correct when
     made and, on the Closing Date, will be true and correct.  Lessee further
     affirms its liability to the Trustee for all of its obligations and duties
     under the Assigned Documents.  In reliance upon US Airways' agreement to be
     responsible therefor and US Airways' performance thereof, Lessee
     acknowledges and agrees that Trustee shall not be bound by or subject to
     any of the duties obligating or responsibilities described in Section 4 of
     the Assignment.
<PAGE>
 
                                                                     PAGE 2 OF 4

4.   Notices.  Pursuant to Section 19.2 of the Lease and Section 7.5 of the
     -------
     Supplementary Agreement, all requests, notices and other communications to
     the "Lessor" shall, from the date of this Consent, be addressed to the
     Trustee, as follows (or to such other address as the Trustee shall specify
     from time to time):

                    First Security Bank, National Association
                    Corporate Trust Department
                    79 South Main Street - 3rd Floor
                    Salt Lake City, Utah 84111
                    Attention: Corporate Trust Administration

                    with copies to:

                    S-C Domestic Holdings VII LLC
                    c/o Curacao Corporation Company N.V.
                    Kaya Flamboyan 9
                    Willemstad, Curacao N.A.
                    Attention: Ben Jansen
                    Facsimile: 5999 32 20 01
 
                    and

                    Soros Fund Management LLC
                    888 Seventh Avenue
                    New York, New York 10106
                    Attention: Michael C. Neus
                    Facsimile: 212-664-0544

                    and

                    C-S Aviation Services, Inc.
                    888 Seventh Avenue, Suite 2901
                    New York, New York 10106
                    Attention: Thomas Seery
                    Facsimile: 212-246-0102

5.   Payments.  All payments other than Hourly Rent to be made to "Lessor" under
     --------
     the Assigned Documents shall, from the date of this Consent, be made to the
     following bank account (or to such other account as the Trustee shall
     specify from time to time):
 
                    Citibank New York
                    ABA No.:       021 000 089
                    Account Name:  For further credit to       
                                Citibank London
                    Account No.:   10990765
                    Account Name:  S-C Domestic Holdings II LLC
                    Account No.:   8228825
<PAGE>
 
                                                                     PAGE 3 OF 4



          All payments of Hourly Rent to be made to "Lessor" under the Assigned
     Documents shall, from the date of this Consent, be made to the following
     bank account (or such other account as the Trustee shall specify from time
     to time):
 
                    Citibank New York
                    ABA No.:       021 000 089
                    Account Name:  For further credit
                                   to Citibank London
                    Account No.:   10990765
                    Account Name:  S-C Aircraft Holdings LLC
                    Account No.:   8300631

6.   Insurance.  Lessee will cooperate in having the Trustee, the S-C Parties
     ---------
     and US Airways named as additional insureds under the liability insurance,
     and the Trustee named as sole loss payee under the hull insurance procured
     by Lessee under the Lease.

7.   Miscellaneous.  This Consent may be executed by the parties hereto in
     -------------
     separate counterparts, each fully executed set of which when so executed
     and delivered shall be an original, but all such counterparts shall
     together constitute but one and the same instrument. This Consent shall be
     governed by the laws of the State of New York.  The respective rights and
     obligations set forth in this Consent shall be binding on and inure to the
     benefit of the parties hereto and their respective successors and assigns.
<PAGE>
 
                                                                     PAGE 4 OF 4


     The undersigned has executed this Acknowledgement and Consent.


                                                 Frontier Airlines, Inc.

                                                 By: ___________________________

                                                 Title: ________________________


Agreed:

First Security Bank, National
  Association, as Trustee

By: ___________________________

Title: ________________________
<PAGE>
 
                                                                     EXHIBIT "A"


                      ASSIGNMENT AND ASSUMPTION AGREEMENT
                      -----------------------------------

          ASSIGNMENT AND ASSUMPTION AGREEMENT (this "Assignment"), dated as of
March 28, 1997, by and between US Airways, Inc. ("US Airways"), a Delaware
corporation, formerly known as USAir, Inc., and FIRST SECURITY BANK, NATIONAL
ASSOCIATION, a national banking association, not in its individual capacity but
solely as Owner Trustee ("Trustee").

                                   RECITALS:
                                   --------

          US Airways and Trustee desire to effect (a) the transfer by US Airways
to Trustee of all of the right, title and interest of US Airways (except as
excluded in Section 4 below) in, under and with respect to, among other things,
(i) the Aircraft Lease Agreement (as supplemented by the Lease Supplement
defined below, and to the extent relating to the Aircraft, the "Lease"), dated
as of July 26, 1994, between US Airways and Frontier Airlines, Inc. (the,
"Lessee"), as supplemented by Lease Supplement No. 1, dated July 26, 1994 (the
"Lease Supplement"), (ii) Supplementary Agreement, dated as of June 6, 1994
between US Airways and Lessee, as it relates to the Aircraft (defined below),
(iii) all certificates, opinions, and other documents relating to the Operative
Document as they relate to the Boeing 737-201 airframe with manufacturer's
serial number 20212 and United States Registration Number N212US and the Pratt &
Whitney model JT8D-9A aircraft engines (which engines have 750 or more rated
takeoff horsepower or the equivalent) with manufacturer's serial numbers 667191
and 667215 (such airframe and the engines (as further defined in the Lease), the
"Aircraft") (all of the foregoing collectively, the "Assigned Documents"), (iv)
the Aircraft, (v) the Hourly Rent Balances and the security deposits of Lessee
as they relate to the Aircraft (collectively, the "Assigned Accounts"), and (vi)
the proceeds from all of the foregoing; and (b) the assumption by Trustee of the
obligations of US Airways (except as excluded in Section 4 below) to the extent
arising after the Effective Date under the Assigned Documents. The Lease was
recorded by the Federal Aviation Administration on August 22, 1994 and assigned
Conveyance No. EE007565. The Lease Supplement was recorded by the Federal
Aviation Administration on August 22, 1994 and assigned Conveyance No. EE007565.

          NOW, THEREFORE, in consideration of the mutual agreements contained
herein, it is hereby agreed as follows:

          1.  Definitions.  Capitalized terms used herein without definition 
              -----------
shall have meaning ascribed thereto in the 
<PAGE>
 
Lease unless the context in which such term is used requires another meaning.

          2.  Assignment.  US Airways does hereby sell, convey, assign, 
              ----------
transfer and set over to Trustee, effective as of the date first above written
(the "Effective Date"), all of its right, title and interest in, under and to
the Assigned Documents, the Assigned Accounts and all other contracts,
agreements, documents or instruments in respect of the aircraft to which US
Airways is a party and relating to the Operative Agreements or the Aircraft and
any proceeds therefrom, together with all other documents and instruments
evidencing any of such right, title and interest.

          3.  Assumption.  Trustee hereby undertakes and assumes all of the 
              ----------
duties and obligations of US Airways relating to the period after the Effective
Date pursuant to the Assigned Documents and any other contracts, agreements,
documents or instruments relating thereto to which US Airways is a party or by
which it is bound, and hereby confirms that it shall be deemed a party to and be
bound by the Assigned Documents and each other contract, agreement, document or
instrument in respect of the Aircraft relating thereto to which US Airways is a
party or by which it is bound as if named therein as "Lessor".

          4.  Excluded Obligations.  Notwithstanding anything to the contrary 
              --------------------
set forth in this Assignment, US Airways is not assigning to Trustee and US
Airways shall remain responsible for, and Trustee is not assuming from US
Airways: (a) the duties and obligations described on Schedule A, (b) the duties
and obligations of US Airways that relate to any period on or prior to the
Effective Date, (c) any other duties and obligations of US Airways relating to
parts or engine consignments, spare parts or spare engines, and (d) without
limiting the foregoing, the right of US Airways to receive any Rent due or
accrued to US Airways prior to the Effective Date and any indemnity relating to
events occurring prior to the Effective Date.
 
          5.  Release of US Airways. Except for obligations not assumed as 
              ---------------------
provided in Section 4 hereof and for which US Airways shall remain responsible,
US Airways shall have no further duty or obligation to Lessee under the Assigned
Documents, the Assigned Accounts or under any other contract, agreement,
document or other instrument relating thereto to which US Airways is a party or
by which it is bound (other than this Agreement).

          6.  Further Assignment.  In furtherance of the within assignments, 
              ------------------
US Airways assigns and grants to Trustee all right to collect for the account of
Trustee all items sold, transferred or assigned to Trustee pursuant hereto; to
institute and prosecute all proceedings that Trustee may deem proper in order to
collect, assert or enforce any claim, right or title of any 
<PAGE>
 
kind in or to the items sold, transferred or assigned; to defend and compromise
any and all actions, suits or proceedings as to title to or interest in the
Aircraft or any of the property acquired by Trustee; and to do all such acts and
things in relating thereto as Trustee shall deem advisable.

          7.  Payments.  US Airways hereby covenants and agrees to pay over to
              --------
Trustee, if and when received following the Effective Date, any amounts
(including any sums payable as interest in respect thereof) paid to or for the
benefit of US Airways that, under Section 2 hereof, belong to Trustee, and
Trustee hereby covenants and agrees to pay over to US Airways, if and when
received following the Effective Date, any amounts (including any sums payable
as interest in respect thereof) paid to or for the benefit of Trustee that,
under Section 2 hereof, belong to US Airways.

          8.  Further Assurances.  Each party to this Assignment and 
              ------------------
Assumption Agreement agrees to execute, acknowledge, deliver, file, record and
publish such further certificates, amendments, instruments or documents, and to
do all such further acts and things, as may be required by law, or as may
reasonably be necessary or advisable to carry out the intents and purposes of
this Assignment and Assumption Agreement.

          9.  Expenses.  Each party hereto shall bear its own legal fees 
              --------
incurred in connection with the transactions described herein.

         10.  Governing Law.  This Assignment and Assumption Agreement shall 
              -------------
be governed by and construed in accordance with the laws of the State of New
York.

         11.  Headings.  Section headings used in this Assignment are for 
              --------
convenience only and shall not be used in interpreting or construing this
Assignment and Assumption Agreement and shall not affect the meaning or
construction of this Assignment and Assumption Agreement.

         12.  Notices.  All notices and other communications hereunder shall 
              -------
be in writing and shall be deemed given if delivered to the parties at the
following addresses (or at such other address for a party as shall be specified
by like notice):

          a.  If to US Airways:
              ----------------
              US Airways, Inc.
              2345 Crystal Drive
              Arlington, Virginia 22227
              Attention: Director - Aircraft Sales
              Facsimile: 703-418-7515
<PAGE>
 
              with a copy at the same address to the attention of US Airways'
              General Counsel, facsimile number (703) 418-5252

          b.  If to Trustee:
              -------------
              First Security Bank, National Association
              79 South Main Street, 3rd Floor
              Salt Lake City, Utah 84111
              Attention: Corporate Trust Administration
              Facsimile: 801-246-5053

         13.  Entire Agreement.  This Assignment constitutes the entire 
              ----------------
agreement among the parties hereto and supersedes all prior agreements and
understandings, both written and oral, with respect to the subject matter
hereof. There are no representations and warranties of any party hereto except
as expressly set forth herein.

    14.  Survival of Representations and Warranties.  All representations and
         ------------------------------------------
warranties contained in this Assignment shall survive the Effective Date.

    15.  Counterparts.  This Assignment may be executed by the parties hereto in
         ------------
separate counterparts, each of which when so executed and delivered shall be an
original, but all such counterparts shall together constitute but one and the
same instrument.

    16.  Successors and Assigns.  The respective rights and obligations set 
         ----------------------
forth in this Assignment shall be binding on and inure to the benefit of the
parties hereto and their respective successors and assigns.

                 [remainder of page left blank intentionally]
<PAGE>
 
     IN WITNESS WHEREOF, the parties hereto have duly executed this Assignment
and Assumption Agreement as of the day and year set forth above.


                                                US AIRWAYS, INC.

                                                BY: ____________________________
 
                                                NAME: __________________________

                                                TITLE: _________________________

                                                DATED: _________________________


                                                FIRST SECURITY BANK, NATIONAL
                                                  ASSOCIATION, AS OWNER TRUSTEE
 
                                                BY: ____________________________
 
                                                NAME: __________________________

                                                TITLE: _________________________

                                                DATED: _________________________
<PAGE>
 
                                                                      SCHEDULE A



                             Excluded Obligations
                             --------------------

     (a)  (S)2.6 of the Supplementary Agreement (license of maintenance and
          weight and balance programs)

     (b)  (S)4.2(f) of the Supplementary Agreement (US Airways' representations)

     (c)  (S)5.2(f) of the Supplementary Agreement (sub-clause (i), second
          sentence (hushkit procurement assistance); sub-clause (ii) first,
          second and third sentences (DFDR Program))

     (d)  (S)5.3 of the Supplementary Agreement (spare parts consignment)

     (e)  (S)5.4 of the Supplementary Agreement (US Airways-provided maintenance
          work)

     (f)  Without limiting the applicability or scope of the foregoing, all
          obligations of US Airways to Lessee arising under the Assigned
          Documents which shall have arisen or occurred on or before the date
          set forth in the introductory paragraph of this Assignment.

EACH OF THE FOREGOING EXCLUDED OBLIGATIONS DESCRIBED IN PARAGRAPHS (A) - (E)
SHALL REMAIN THE OBLIGATIONS OF US AIRWAYS DURING THE BASE LEASE TERM AND ANY
RENEWAL TERM.
<PAGE>
 
                          Acknowledgement and Consent
                          ---------------------------

Acknowledgement and Consent (this "Consent") of Frontier Airlines, Inc. dated as
of March 28, 1997.

Recitals: US Airways, Inc., (formerly USAir, Inc., "US Airways"), as lessor and
--------
Frontier Airlines, Inc. ("Lessee"), as lessee, entered into that certain Lease
Agreement dated as of July 26, 1994 (the "Lease") whereby US Airways agreed to
lease to Lessee and Lessee agreed to lease from US Airways the Boeing 737-201
Airframe and the Engines identified in the Assignment (defined below).  US
Airways and First Security Bank, National Association, not in its individual
capacity but solely as Owner Trustee ("Trustee"), as trustee for the S-C
Parties, have entered into an Assignment and Assumption Agreement (the
"Assignment") dated as of March 28, 1997, whereby US Airways has assigned to the
Trustee all of the right, title and interest of US Airways in and to the
Assigned Documents and the Aircraft.  The Trustee desires that Lessee
acknowledge and consent to the Assignment and reaffirm its representations,
warranties and obligations to the Trustee.

     Accordingly, the Trustee and Lessee agree as follows:

1.   Defined Terms.  Unless otherwise defined herein or the context requires
     -------------
     otherwise, all capitalized terms used herein shall have the meanings
     assigned to them in the Assignment.

2.   Acknowledgement and Consent.  Lessee hereby acknowledges and consents to
     ---------------------------
     the Assignment (a copy of which is attached hereto as Exhibit "A"), and all
     of the terms and conditions contained therein.

3.   Representations, Warranties and Obligations.  All representations and
     -------------------------------------------
     warranties of Lessee in the Assigned Documents were true and correct when
     made and, on the Closing Date, will be true and correct.  Lessee further
     affirms its liability to the Trustee for all of its obligations and duties
     under the Assigned Documents.  In reliance upon US Airways' agreement to be
     responsible therefor and US Airways' performance thereof, Lessee
     acknowledges and agrees that Trustee shall not be bound by or subject to
     any of the duties obligating or responsibilities described in Section 4 of
     the Assignment.
<PAGE>
 
                                                            PAGE 2 OF 4

4.   Notices.  Pursuant to Section 19.2 of the Lease and Section 7.5 of the
     -------
     Supplementary Agreement, all requests, notices and other communications to
     the "Lessor" shall, from the date of this Consent, be addressed to the
     Trustee, as follows (or to such other address as the Trustee shall specify
     from time to time):

                First Security Bank, National Association
                Corporate Trust Department
                79 South Main Street - 3rd Floor
                Salt Lake City, Utah 84111
                Attention: Corporate Trust Administration

                with copies to:

                S-C Domestic Holdings VII LLC
                c/o Curacao Corporation Company N.V.
                Kaya Flamboyan 9
                Willemstad, Curacao N.A.
                Attention: Ben Jansen
                Facsimile: 5999 32 20 01
 
                and

                Soros Fund Management LLC
                888 Seventh Avenue
                New York, New York 10106
                Attention: Michael C. Neus
                Facsimile: 212-664-0544

                and

                C-S Aviation Services, Inc.
                888 Seventh Avenue, Suite 2901
                New York, New York 10106
                Attention: Thomas Seery
                Facsimile: 212-246-0102

5.   Payments.  All payments other than Hourly Rent to be made to "Lessor" under
     --------
     the Assigned Documents shall, from the date of this Consent, be made to the
     following bank account (or to such other account as the Trustee shall
     specify from time to time):

                Citibank New York
                ABA No.:         021 000 089
                Account Name:    Further Credit to             
                                 Citibank London
                Account No.:     10990765
                Account Name:    S-C Domestic Holdings II LLC
                Account No.:     8228825
<PAGE>
 
                                                            PAGE 3 OF 4

        All payments of Hourly Rent to be made to "Lessor" under the Assigned 
Documents shall, from the date of this Consent, be made to the following bank
account (or such other account as the Trustee shall specify from time to time):
 
                Citibank New York
                ABA No.:          021 000 089
                Account Name:     For further credit
                                  to Citibank London
                Account No.:      10990765
                Account Name:     S-C Aircraft Holdings LLC
                Account No.:      8300631
 
6.   Insurance.  Lessee will cooperate in having the Trustee, the S-C Parties
     ---------
     and US Airways named as additional insureds under the liability insurance,
     and the Trustee named as sole loss payee under the hull insurance procured
     by Lessee under the Lease.

7.   Miscellaneous.  This Consent may be executed by the parties hereto in
     -------------
     separate counterparts, each fully executed set of which when so executed
     and delivered shall be an original, but all such counterparts shall
     together constitute but one and the same instrument. This Consent shall be
     governed by the laws of the State of New York.  The respective rights and
     obligations set forth in this Consent shall be binding on and inure to the
     benefit of the parties hereto and their respective successors and assigns.
<PAGE>
 
                                                            PAGE 4 OF 4


        The undersigned has executed this Acknowledgement and Consent.


                                Frontier Airlines, Inc.

                                By: ___________________________

                                Title: ________________________


Agreed:

First Security Bank, National
 Association, as Trustee

By: ___________________________

Title: ________________________
<PAGE>
 
                                                            EXHIBIT "A"

                      ASSIGNMENT AND ASSUMPTION AGREEMENT
                      -----------------------------------

        ASSIGNMENT AND ASSUMPTION AGREEMENT (this "Assignment"), dated as of
March 28, 1997, by and between US Airways, Inc. ("US Airways"), a Delaware
corporation, formerly known as USAir, Inc., and FIRST SECURITY BANK, NATIONAL
ASSOCIATION, a national banking association, not in its individual capacity but
solely as Owner Trustee ("Trustee").

                                   RECITALS:
                                   ---------

        US Airways and Trustee desire to effect (a) the transfer by US Airways
to Trustee of all of the right, title and interest of US Airways (except as
excluded in Section 4 below) in, under and with respect to, among other things,
(i) the Aircraft Lease Agreement (as supplemented by the Lease Supplement
defined below, and to the extent relating to the Aircraft, the "Lease"), dated
as of July 26, 1994, between US Airways and Frontier Airlines, Inc. (the,
"Lessee"), as supplemented by Lease Supplement No. 3, dated July 27, 1994 (the
"Lease Supplement"), (ii) Supplementary Agreement, dated as of June 6, 1994
between US Airways and Lessee, as it relates to the Aircraft (defined below),
(iii) all certificates, opinions, and other documents relating to the Operative
Document as they relate to the Boeing 737-201 airframe with manufacturer's
serial number 20214 and United States Registration Number N214AU and the Pratt &
Whitney model JT8D-9A aircraft engines (which engines have 750 or more rated
takeoff horsepower or the equivalent) with manufacturer's serial numbers 653726
and 707333 (such airframe and the engines (as further defined in the Lease), the
"Aircraft") (all of the foregoing collectively, the "Assigned Documents"), (iv)
the Aircraft, (v) the Hourly Rent Balances and the security deposits of Lessee
as they relate to the Aircraft (collectively, the "Assigned Accounts"), and (vi)
the proceeds from all of the foregoing; and (b) the assumption by Trustee of the
obligations of US Airways (except as excluded in Section 4 below) to the extent
arising after the Effective Date under the Assigned Documents. The Lease was
recorded by the Federal Aviation Administration on August 22, 1994 and assigned
Conveyance No. EE007565. The Lease Supplement was recorded by the Federal
Aviation Administration on August 22, 1994 and assigned Conveyance No. EE007565.

        NOW, THEREFORE, in consideration of the mutual agreements contained
herein, it is hereby agreed as follows:

        1.  Definitions. Capitalized terms used herein without definition shall
            -----------
have meaning ascribed thereto in the Lease unless the context in which such term
is used requires another meaning.
<PAGE>
 
        2.  Assignment. US Airways does hereby sell, convey, assign, transfer
            ----------
and set over to Trustee, effective as of the date first above written (the
"Effective Date"), all of its right, title and interest in, under and to the
Assigned Documents, the Assigned Accounts and all other contracts, agreements,
documents or instruments in respect of the aircraft to which US Airways is a
party and relating to the Operative Agreements or the Aircraft and any proceeds
therefrom, together with all other documents and instruments evidencing any of
such right, title and interest.

        3.  Assumption. Trustee hereby undertakes and assumes all of the duties
            ----------
and obligations of US Airways relating to the period after the Effective Date
pursuant to the Assigned Documents and any other contracts, agreements,
documents or instruments relating thereto to which US Airways is a party or by
which it is bound, and hereby confirms that it shall be deemed a party to and be
bound by the Assigned Documents and each other contract, agreement, document or
instrument in respect of the Aircraft relating thereto to which US Airways is a
party or by which it is bound as if named therein as "Lessor".

        4.  Excluded Obligations. Notwithstanding anything to the contrary set
            --------------------
forth in this Assignment, US Airways is not assigning to Trustee and US Airways
shall remain responsible for, and Trustee is not assuming from US Airways: (a)
the duties and obligations described on Schedule A, (b) the duties and
obligations of US Airways that relate to any period on or prior to the Effective
Date, (c) any other duties and obligations of US Airways relating to parts or
engine consignments, spare parts or spare engines, and (d) without limiting the
foregoing, the right of US Airways to receive any Rent due or accrued to US
Airways prior to the Effective Date and any indemnity relating to events
occurring prior to the Effective Date.
 
        5.  Release of US Airways. Except for obligations not assumed as
            ---------------------
provided in Section 4 hereof and for which US Airways shall remain responsible,
US Airways shall have no further duty or obligation to Lessee under the Assigned
Documents, the Assigned Accounts or under any other contract, agreement,
document or other instrument relating thereto to which US Airways is a party or
by which it is bound (other than this Agreement).

        6.  Further Assignment. In furtherance of the within assignments, US
            ------------------
Airways assigns and grants to Trustee all right to collect for the account of
Trustee all items sold, transferred or assigned to Trustee pursuant hereto; to
institute and prosecute all proceedings that Trustee may deem proper in order to
collect, assert or enforce any claim, right or title of any kind in or to the
items sold, transferred or assigned; to defend and compromise any and all
actions, suits or proceedings as to title to or interest in the Aircraft or any
of the property acquired by Trustee; and to do all such acts and things in
relating thereto as Trustee shall deem advisable.
<PAGE>
 
        7.  Payments. US Airways hereby covenants and agrees to pay over to
            --------
Trustee, if and when received following the Effective Date, any amounts
(including any sums payable as interest in respect thereof) paid to or for the
benefit of US Airways that, under Section 2 hereof, belong to Trustee, and
Trustee hereby covenants and agrees to pay over to US Airways, if and when
received following the Effective Date, any amounts (including any sums payable
as interest in respect thereof) paid to or for the benefit of Trustee that,
under Section 2 hereof, belong to US Airways.

        8.  Further Assurances. Each party to this Assignment and Assumption
            ------------------
Agreement agrees to execute, acknowledge, deliver, file, record and publish such
further certificates, amendments, instruments or documents, and to do all such
further acts and things, as may be required by law, or as may reasonably be
necessary or advisable to carry out the intents and purposes of this Assignment
and Assumption Agreement.

        9.  Expenses. Each party hereto shall bear its own legal fees incurred
            --------
in connection with the transactions described herein.

        10. Governing Law. This Assignment and Assumption Agreement shall be
            -------------
governed by and construed in accordance with the laws of the State of New York.

        11. Headings. Section headings used in this Assignment are for
            --------
convenience only and shall not be used in interpreting or construing this
Assignment and Assumption Agreement and shall not affect the meaning or
construction of this Assignment and Assumption Agreement.

        12. Notices.  All notices and other communications hereunder shall be in
            -------
writing and shall be deemed given if delivered to the parties at the following
addresses (or at such other address for a party as shall be specified by like
notice):

            a.   If to US Airways:
                 -----------------
                 US Airways, Inc.
                 2345 Crystal Drive
                 Arlington, Virginia 22227
                 Attention: Director - Aircraft Sales
                 Facsimile: 703-418-7515
<PAGE>
 
                 with a copy at the same address to the attention of US Airways'
                 General Counsel, facsimile number (703) 418-5252

            b.   If to Trustee:
                 --------------
                 First Security Bank, N.A.
                 79 South Main Street, 3rd Floor
                 Salt Lake City, Utah 84111
                 Attention: Corporate Trust Administration
                 Facsimile: 801-246-5053

        13. Entire Agreement. This Assignment constitutes the entire agreement
            ----------------
among the parties hereto and supersedes all prior agreements and understandings,
both written and oral, with respect to the subject matter hereof. There are no
representations and warranties of any party hereto except as expressly set forth
herein.

        14. Survival of Representations and Warranties. All representations and
            ------------------------------------------
warranties contained in this Assignment shall survive the Effective Date.

        15. Counterparts. This Assignment may be executed by the parties hereto
            ------------
in separate counterparts, each of which when so executed and delivered shall be
an original, but all such counterparts shall together constitute but one and the
same instrument.

        16. Successors and Assigns. The respective rights and obligations set
            ----------------------
forth in this Assignment shall be binding on and inure to the benefit of the
parties hereto and their respective successors and assigns.

                 [remainder of page left blank intentionally]
<PAGE>
 
        IN WITNESS WHEREOF, the parties hereto have duly executed this
Assignment and Assumption Agreement as of the day and year set forth above.


                                US AIRWAYS, INC.

                                BY: ____________________________
 
                                NAME: __________________________

                                TITLE: _________________________

                                DATED: _________________________


                                FIRST SECURITY BANK, NATIONAL
                                ASSOCIATION, AS OWNER TRUSTEE
 
                                BY: ____________________________
 
                                NAME: __________________________

                                TITLE: _________________________

                                DATED: _________________________
<PAGE>
 
                                                            SCHEDULE A


                             Excluded Obligations
                             ---------------------

     (a)  (S)2.6 of the Supplementary Agreement (license of maintenance and
          weight and balance programs)

     (b)  (S)4.2(f) of the Supplementary Agreement (US Airways' representations)

     (c)  (S)5.2(f) of the Supplementary Agreement (sub-clause (i), second
          sentence (hushkit procurement assistance); sub-clause (ii) first,
          second and third sentences (DFDR Program))

     (d)  (S)5.3 of the Supplementary Agreement (spare parts consignment)

     (e)  (S)5.4 of the Supplementary Agreement (US Airways-provided maintenance
          work)

     (f)  Without limiting the applicability or scope of the foregoing, all
          obligations of US Airways to Lessee arising under the Assigned
          Documents which shall have arisen or occurred on or before the date
          set forth in the introductory paragraph of this Assignment.

EACH OF THE FOREGOING EXCLUDED OBLIGATIONS DESCRIBED IN PARAGRAPHS (A) - (E)
SHALL REMAIN THE OBLIGATIONS OF US AIRWAYS DURING THE BASE LEASE TERM AND ANY
RENEWAL TERM.
<PAGE>
 
                          Acknowledgement and Consent
                          ---------------------------

Acknowledgement and Consent (this "Consent") of Frontier Airlines, Inc. dated as
of March 20, 1997.

Recitals: US Airways, Inc. (formerly USAir, Inc., "US Airways"), as lessor and
--------
Frontier Airlines, Inc. ("Lessee"), as lessee, entered into that certain Lease
Agreement dated as of July 26, 1994 (the "Lease") whereby US Airways agreed to
lease to Lessee and Lessee agreed to lease from US Airways the Boeing 737-201
Airframe and the Engines identified in the Assignment (defined below).  US
Airways and First Security Bank, National Association, not in its individual
capacity but solely as Owner Trustee ("Trustee"), as trustee for the S-C
Parties, have entered into an Assignment and Assumption Agreement (the
"Assignment") dated as of March 20, 1997, whereby US Airways has assigned to the
Trustee all of the right, title and interest of US Airways in and to the
Assigned Documents and the Aircraft.  The Trustee desires that Lessee
acknowledge and consent to the Assignment and reaffirm its representations,
warranties and obligations to the Trustee.

        Accordingly, the Trustee and Lessee agree as follows:

1.      Defined Terms.  Unless otherwise defined herein or the context requires
        -------------
        otherwise, all capitalized terms used herein shall have the meanings
        assigned to them in the Assignment.

2.      Acknowledgement and Consent. Lessee hereby acknowledges and consents to
        ---------------------------
        the Assignment (a copy of which is attached hereto as Exhibit "A"), and
        all of the terms and conditions contained therein.

3.      Representations, Warranties and Obligations. All representations and
        -------------------------------------------
        warranties of Lessee in the Assigned Documents were true and correct
        when made and, on the Closing Date, will be true and correct. Lessee
        further affirms its liability to the Trustee for all of its obligations
        and duties under the Assigned Documents. In reliance upon US Airways'
        agreement to be responsible therefor and US Airways' performance
        thereof, Lessee acknowledges and agrees that Trustee shall not be bound
        by or subject to any of the duties obligating or responsibilities
        described in Section 4 of the Assignment.
<PAGE>
 
                                                            PAGE 2 OF 4

4.   Notices.  Pursuant to Section 19.2 of the Lease and Section 7.5 of the
     -------
     Supplementary Agreement, all requests, notices and other communications to
     the "Lessor" shall, from the date of this Consent, be addressed to the
     Trustee, as follows (or to such other address as the Trustee shall specify
     from time to time):

                First Security Bank, National Association
                Corporate Trust Department
                79 South Main Street - 3rd Floor
                Salt Lake City, Utah 84111
                Attention: Corporate Trust Administration

                with copies to:

                S-C Domestic Holdings VII LLC
                c/o Curacao Corporation Company N.V.
                Kaya Flamboyan 9
                Willemstad, Curacao N.A.
                Attention: Ben Jansen
                Facsimile: 5999 32 20 01
 
                and

                Soros Fund Management LLC
                888 Seventh Avenue
                New York, New York 10106
                Attention: Michael C. Neus
                Facsimile: 212-664-0544

                and

                C-S Aviation Services, Inc.
                888 Seventh Avenue, Suite 2901
                New York, New York 10106
                Attention: Thomas Seery
                Facsimile: 212-246-0102

5.   Payments.  All payments other than Hourly Rent to be made to "Lessor" under
     --------
     the Assigned Documents shall, from the date of this Consent, be made to the
     following bank account (or to such other account as the Trustee shall
     specify from time to time):
 
                Citibank New York
                ABA No.:        021 000 089
                Account Name:   For further credit to         
                                Citibank London
                Account No.:    10990765
                Account Name:   S-C Domestic Holdings II LLC
                Account No.     8228825
<PAGE>
 
                                                            PAGE 3 OF 4

 
        All payments of Hourly Rent to be made to "Lessor" under the Assigned
     Documents shall, from the date of this Consent, be made to the following
     bank account (or such other account as the Trustee shall specify from time
     to time):
 
                Citibank New York
                ABA No.:                021 000 089
                Account Name:           For further credit
                                        to Citibank London
                Account No.:            10990765
                Account Name:           S-C Aircraft Holdings LLC
                Account No.:            8300631


6.      Insurance. Lessee will cooperate in having the Trustee, the S-C Parties
        ---------
        and US Airways named as additional insureds under the liability
        insurance, and the Trustee named as sole loss payee under the hull
        insurance procured by Lessee under the Lease.

7.      Miscellaneous. This Consent may be executed by the parties hereto in
        -------------
        separate counterparts, each fully executed set of which when so executed
        and delivered shall be an original, but all such counterparts shall
        together constitute but one and the same instrument. This Consent shall
        be governed by the laws of the State of New York. The respective rights
        and obligations set forth in this Consent shall be binding on and inure
        to the benefit of the parties hereto and their respective successors and
        assigns.
<PAGE>
 
                                                            PAGE 4 OF 4


        The undersigned has executed this Acknowledgement and Consent.


                                Frontier Airlines, Inc.

                                By: ___________________________

                                Title: ________________________


Agreed:

First Security Bank, National
 Association, as Trustee

By: ___________________________

Title: ________________________
<PAGE>
 
                                                            EXHIBIT "A"

                      ASSIGNMENT AND ASSUMPTION AGREEMENT
                      -----------------------------------

        ASSIGNMENT AND ASSUMPTION AGREEMENT (this "Assignment"), dated as of
March 20, 1997, by and between US Airways, Inc. ("US Airways"), a Delaware
corporation, formerly known as USAir, Inc. and FIRST SECURITY BANK, NATIONAL
ASSOCIATION, a national banking association, not in its individual capacity but
solely as Owner Trustee ("Trustee").

                                   RECITALS:
                                   ---------

        US Airways and Trustee desire to effect (a) the transfer by US Airways
to Trustee of all of the right, title and interest of US Airways (except as
excluded in Section 4 below) in, under and with respect to, among other things,
(i) the Aircraft Lease Agreement (as supplemented by the Lease Supplement
defined below, and to the extent relating to the Aircraft, the "Lease"), dated
as of July 26, 1994, between US Airways and Frontier Airlines, Inc. (the,
"Lessee"), as supplemented by Lease Supplement No. 5, dated October 4, 1994 (the
"Lease Supplement"), (ii) Supplementary Agreement, dated as of June 6, 1994
between US Airways and Lessee, as it relates to the Aircraft (defined below),
(iii) all certificates, opinions, and other documents relating to the Operative
Document as they relate to the Boeing 737-201 airframe with manufacturer's
serial number 20215 and United States Registration Number N217US and the Pratt &
Whitney model JT8D-9A aircraft engines (which engines have 750 or more rated
takeoff horsepower or the equivalent) with manufacturer's serial numbers 667241
and 667213 (such airframe and the engines (as further defined in the Lease), the
"Aircraft") (all of the foregoing collectively, the "Assigned Documents"), (iv)
the Aircraft, (v) the Hourly Rent Balances and the security deposits of Lessee
as they relate to the Aircraft (collectively, the "Assigned Accounts"), and (vi)
the proceeds from all of the foregoing; and (b) the assumption by Trustee of the
obligations of US Airways (except as excluded in Section 4 below) to the extent
arising after the Effective Date. The Lease was recorded by the Federal Aviation
Administration on August 22, 1994 and assigned Conveyance No. EE007565. The
Lease Supplement was recorded by the Federal Aviation Administration on November
7, 1994 and assigned Conveyance No. LL08355.

        NOW, THEREFORE, in consideration of the mutual agreements contained
herein, it is hereby agreed as follows:

1.      Definitions. Capitalized terms used herein without definition shall have
        -----------
meaning ascribed thereto in the Lease unless the context in which such term is
used requires another meaning.
<PAGE>
 
2.  Assignment.  US Airways does hereby sell, convey, assign, transfer and set
    ----------
over to Trustee, effective as of the date first above written (the "Effective
Date"), all of its right, title and interest in, under and to the Assigned
Documents, the Assigned Accounts and all other contracts, agreements, documents
or instruments in respect of the aircraft to which US Airways is a party and
relating to the Operative Agreements or the Aircraft and any proceeds therefrom,
together with all other documents and instruments evidencing any of such right,
title and interest.

3.  Assumption.  Trustee hereby undertakes and assumes all of the duties and
    ----------
obligations of US Airways relating to the period after the Effective Date
pursuant to the Assigned Documents and any other contracts, agreements,
documents or instruments relating thereto to which US Airways is a party or by
which it is bound, and hereby confirms that it shall be deemed a party to and be
bound by the Assigned Documents and each other contract, agreement, document or
instrument in respect of the Aircraft relating thereto to which US Airways is a
party or by which it is bound as if named therein as "Lessor".

4.  Excluded Obligations.  Notwithstanding anything to the contrary set forth in
    --------------------
this Assignment, US Airways is not assigning to Trustee and US Airways shall
remain responsible for, and Trustee is not assuming from US Airways:  (a) the
duties and obligations described on Schedule A, (b) the duties and obligations
of US Airways that relate to any period on or prior to the Effective Date, (c)
any other duties and obligations of US Airways relating to parts or engine
consignments, spare parts or spare engines, and (d) without limiting the
foregoing, the right of US Airways to receive any Rent due or accrued to US
Airways prior to the Effective Date and any indemnity relating to events
occurring prior to the Effective Date.
 
5.  Release of US Airways. Except for obligations not assumed as provided in
    ---------------------
Section 4 hereof and for which US Airways shall remain responsible, US Airways
shall have no further duty or obligation to Lessee under the Assigned Documents,
the Assigned Accounts or under any other contract, agreement, document or other
instrument relating thereto to which US Airways is a party or by which it is
bound (other than this Agreement).

6.  Further Assignment.  In furtherance of the within assignments, US Airways
    ------------------
assigns and grants to Trustee all right to collect for the account of Trustee
all items sold, transferred or assigned to Trustee pursuant hereto; to institute
and prosecute all proceedings that Trustee may deem proper in order to collect,
assert or enforce any claim, right or title of any kind in or to the items sold,
transferred or assigned; to defend and compromise any and all actions, suits or
proceedings as to 
<PAGE>
 
title to or interest in the Aircraft or any of the property acquired by Trustee;
and to do all such acts and things in relating thereto as Trustee shall deem
advisable.

7.  Payments.  US Airways hereby covenants and agrees to pay over to Trustee, if
    --------
and when received following the Effective Date, any amounts (including any sums
payable as interest in respect thereof) paid to or for the benefit of US Airways
that, under Section 2 hereof, belong to Trustee, and Trustee hereby covenants
and agrees to pay over to US Airways, if and when received following the
Effective Date, any amounts (including any sums payable as interest in respect
thereof) paid to or for the benefit of Trustee that, under Section 2 hereof,
belong to US Airways.

8.  Further Assurances.  Each party to this Assignment and Assumption Agreement
    ------------------
agrees to execute, acknowledge, deliver, file, record and publish such further
certificates, amendments, instruments or documents, and to do all such further
acts and things, as may be required by law, or as may reasonably be necessary or
advisable to carry out the intents and purposes of this Assignment and
Assumption Agreement.

9.  Expenses.  Each party hereto shall bear its own legal fees incurred in
    --------
connection with the transactions described herein.

10. Governing Law.  This Assignment and Assumption Agreement shall be governed
    -------------
by and construed in accordance with the laws of the State of New York.

11. Headings.  Section headings used in this Assignment are for convenience
    --------
only and shall not be used in interpreting or construing this Assignment and
Assumption Agreement and shall not affect the meaning or construction of this
Assignment and Assumption Agreement.

12. Notices.  All notices and other communications hereunder shall be in
    -------
writing and shall be deemed given if delivered to the parties at the following
addresses (or at such other address for a party as shall be specified by like
notice):

    a.   If to US Airways:
         -----------------
         US Airways, Inc.
         2345 Crystal Drive
         Arlington, Virginia 22227
         Attention: Director - Aircraft Sales
         Facsimile: 703-418-7515

         with a copy at the same address to the attention of US Airways'
         General Counsel, facsimile number (703) 418-5252
<PAGE>
 
    b.   If to Trustee:
         --------------
         First Security Bank, National Association
         79 South Main Street, 3rd Floor
         Salt Lake City, Utah 84111
         Attention: Corporate Trust Administration
         Facsimile: 801-246-5053

13.  Entire Agreement.  This Assignment constitutes the entire agreement among
     ----------------
the parties hereto and supersedes all prior agreements and understandings, both
written and oral, with respect to the subject matter hereof.  There are no
representations and warranties of any party hereto except as expressly set forth
herein.

14.  Survival of Representations and Warranties.  All representations and
     ------------------------------------------
warranties contained in this Assignment shall survive the Effective Date.

15.  Counterparts.  This Assignment may be executed by the parties hereto in
     ------------
separate counterparts, each of which when so executed and delivered shall be an
original, but all such counterparts shall together constitute but one and the
same instrument.

16.  Successors and Assigns.  The respective rights and obligations set forth in
     ----------------------
this Assignment shall be binding on and inure to the benefit of the parties
hereto and their respective successors and assigns.

                 [remainder of page left blank intentionally]
<PAGE>
 
        IN WITNESS WHEREOF, the parties hereto have duly executed this
Assignment and Assumption Agreement as of the day and year set forth above.


                                US AIRWAYS, INC.

                                BY: ____________________________
 
                                NAME: __________________________

                                TITLE: _________________________

                                DATED: _________________________


                                FIRST SECURITY BANK, NATIONAL
                                  ASSOCIATION, AS OWNER TRUSTEE
 
                                BY: ____________________________
 
                                NAME: __________________________

                                TITLE: _________________________

                                DATED: _________________________
<PAGE>
 
                                                            SCHEDULE A


                             Excluded Obligations
                             ---------------------

     (a)  (S)2.6 of the Supplementary Agreement (license of maintenance and
          weight and balance programs)

     (b)  (S)4.2(f) of the Supplementary Agreement (US Airways' representations)

     (c)  (S)5.2(f) of the Supplementary Agreement (sub-clause (i), second
          sentence (hushkit procurement assistance); sub-clause (ii) first,
          second and third sentences (DFDR Program))

     (d)  (S)5.3 of the Supplementary Agreement (spare parts consignment)

     (e)  (S)5.4 of the Supplementary Agreement (US Airways-provided maintenance
          work)

     (f)  Without limiting the applicability or scope of the foregoing, all
          obligations of US Airways to Lessee arising under the Assigned
          Documents which shall have arisen or occurred on or before the date
          set forth in the introductory paragraph of this Assignment.

EACH OF THE FOREGOING EXCLUDED OBLIGATIONS DESCRIBED IN PARAGRAPHS (A) - (E)
SHALL REMAIN THE OBLIGATIONS OF US AIRWAYS DURING THE BASE LEASE TERM AND ANY
RENEWAL TERM.