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                                                                EXHIBIT 10.31(a)

                                                          CONFIDENTIAL TREATMENT
                                                  REQUESTED PURSUANT TO RULE 406

CERTAIN PORTIONS OF THIS EXHIBIT HAVE BEEN OMITTED PURSUANT TO A REQUEST FOR
CONFIDENTIAL TREATMENT UNDER RULE 406 OF THE SECURITIES ACT OF 1933. THE OMITTED
MATERIALS HAVE BEEN FILED SEPARATELY WITH THE SECURITIES AND EXCHANGE
COMMISSION.

                              Amendment Number One
                                       to
                                Delta Connection
                                    Agreement

     This Amendment Number One (this "Amendment"), dated and effective the 7th
day of February, 2003, to the Delta Connection Agreement dated and effective
June 7, 2002 (the "Agreement"), is among Delta Air Lines, Inc., 1030 Delta
Boulevard, Atlanta, Georgia 30320 ("Delta"), Chautauqua Airlines, Inc.
("Chautauqua" or "Operator"), 2500 S. High School Road, Suite 160, Indianapolis,
Indiana 46241 and Republic Airways Holdings, Inc. ("Republic"), 2500 S. High
School Road, Suite 160, Indianapolis, Indiana 46241.

     WHEREAS, Delta, Chautauqua and Republic are parties to the Agreement; and

     WHEREAS, the parties desire to amend the Agreement to add an additional
twelve (12) Embraer ERJ 145 aircraft to the Aircraft to be operated by
Chautauqua pursuant to the terms of the Agreement; and

     NOW, THEREFORE, for and in consideration of the mutual undertakings set
forth herein and other good and valuable consideration, the receipt and
sufficiency of which are hereby acknowledged, Delta, Operator and Republic,
intending to be legally bound, hereby agree as follows:

1.  DEFINED TERMS. All terms capitalized used, but not defined, herein shall
    have the meaning ascribed to such terms in the Agreement.

2.  ADDITION OF AIRCRAFT.

        A.  Pursuant to Article 1(A) of the Agreement, the twelve (12) Embraer
            ERJ 145 aircraft set forth on APPENDIX 1 attached hereto (the "First
            Additional Aircraft") shall be included as "Aircraft" under the
            terms of the Agreement. EXHIBIT A of the Agreement is hereby deleted
            in its entirety and replaced with the new EXHIBIT A attached hereto
            as APPENDIX 2.

        B.  For purposes of the Agreement, the First Additional Aircraft shall
            no longer be deemed Committed Aircraft, Option Aircraft,
            Repositioned Aircraft or Excluded Aircraft.

        C.  The First Additional Aircraft shall be delivered to Delta no later
            than the respective dates set forth on the new EXHIBIT A. Chautauqua
            and Republic, jointly and

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            severally, represent and warrant to Delta that the First Additional
            Aircraft have been maintained in accordance with Operator's FAA
            approved maintenance program, and with the exception of the need to
            repaint and redecorate such aircraft in Delta Connection livery,
            scheduled C-checks and customary maintenance requirements, the First
            Additional Aircraft are fully operable, are able to begin operating
            under the terms of the Agreement as amended, and are not subject to
            any unusual or extraordinary repair or maintenance requirements.

        D.  Each of the First Additional Aircraft shall be appointed in the
            Delta Connection Livery upon delivery, and Chautauqua shall be
            responsible for all costs and expenses associated with modifying the
            First Additional Aircraft to such Livery.

        E.  Delta has reviewed and approved the terms of the respective leases
            for the First Additional Aircraft and acknowledges the prepaid rent
            balance as of December 31, 2002 in the amount set forth for each
            First Additional Aircraft on APPENDIX 1.

3.  COMPENSATION. Delta shall compensate Chautauqua for operating the First
    Additional Aircraft pursuant to the terms and conditions of the Agreement,
    with the following exceptions:

              (i)   The parties acknowledge and agree that the Base Rate costs
                    shall be based upon the model attached hereto as EXHIBIT B.
                    EXHIBIT B of the Agreement is hereby deleted in its entirety
                    and replaced with the new EXHIBIT B attached hereto as
                    APPENDIX 3.

              (ii)  the parties acknowledge and agree that the aircraft rent
                    expense for each of the First Additional Aircraft shall be
                    deemed to be an average of $ [ * ] per month. Mark-Up of the
                    aircraft rent expense shall be capped at a monthly rate of $
                    [ * ]. The parties further acknowledge and agree that Delta
                    shall not be responsible for reimbursing Operator for any
                    such aircraft rent expense until the actual in service date
                    for each First Additional Aircraft.

              (iii) the parties acknowledge and agree that some or all of the
                    First Additional Aircraft will require "C-checks" on their
                    respective airframe. In such event, it is understood and
                    agreed that Delta shall only be responsible for reimbursing
                    Chautauqua a pro-rata portion of the total cost of such
                    C-checks based on the number of flight hours such First
                    Additional Aircraft are operated by Chautauqua for Delta as
                    compared to the total flight hours of operation since the
                    last C-check of the respective aircraft. The parties
                    estimate that for 2003, Delta's pro-rata portion of the
                    total C-check expense will be approximately $ [* ].

              (iv)  the parties acknowledge and agree that engine maintenance
                    costs for each of the First Additional Aircraft shall be
                    incurred pursuant to that certain engine maintenance
                    agreement by and between Chautauqua and Rolls Royce attached
                    hereto as APPENDIX 4. The parties estimate that the
                    estimated engine


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                    maintenance rates will be as follows: Base engine rate -
                    approximately $ [ * ] per engine flight hour; LRP rate-
                    approximately $ [ * ] per engine flight hour; minor FOD
                    coverage - approximately $ [ * ] per EFH; LLP rate -
                    approximately $ [ * ] per EFH. The maintenance rates are at
                    2002 economics and are subject to reasonable escalation and
                    retroactive adjustment for the actual rates based on the
                    actual operations of the aircraft.

4.  WARRANT. Pursuant to Article 19(D) of the Agreement, simultaneously with the
    execution of this Amendment, Republic shall issue to Delta a warrant to
    purchase 720,000 shares of Republic Common Stock in the form attached hereto
    as APPENDIX 5 (the "Additional Warrant").

5.  MISCELLANEOUS.

    A.  This Amendment, together with the Appendices attached hereto, and the
        Additional Warrant, constitute the entire understanding of the parties
        with respect to the subject matter hereof, and any other prior or
        contemporaneous agreements, whether written or oral, are expressly
        superseded hereby.

    B.  The Amendment may be executed in any number of counterparts, each of
        which shall be deemed an original and all of which, taken together,
        shall constitute one and the same instrument.

    C.  Except as specifically stated herein, all other terms and conditions of
        the Agreement shall remain in full force and effect.


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    IN WITNESS WHEREOF, the parties have executed this Amendment by their
undersigned duly authorized representatives:

Republic Airways Holdings, Inc.            Delta Air Lines, Inc.


By:  /s/ Bryan K. Bedford                  By: /s/ Fred Buttrell
    -------------------------------            -----------------------------

Name: Bryan K. Bedford                     Name: Fred Buttrell
      -----------------------------              ---------------------------

Title: President and CEO                   Title: President and CEO, Delta
       ----------------------------               Connection, Inc.
                                                  ----------------------------

Chautauqua Airlines, Inc.

By:  /s/ Bryan K. Bedford
    -------------------------------

Name: Bryan K. Bedford
      -----------------------------

Title: President and CEO
       ----------------------------

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                                   APPENDIX 1

                            FIRST ADDITIONAL AIRCRAFT

<Table>
<Caption>
                     PRE-PAID
           SERIAL   RENT AS OF     DATE OF
AIRCRAFT   NUMBER    12-31-02    MANUFACTURE
--------------------------------------------
<S>        <C>         <C>        <C>
N269SK     145293      [ * ]      07/12/00

N270SK     145304      [ * ]      08/16/00

N271SK     145305      [ * ]      08/28/00

N272SK     145306      [ * ]      09/04/00

N273SK     145331      [ * ]      10/17/00

N274SK     145344      [ * ]      11/16/00

N276SK     145348      [ * ]      11/28/00

N278SK     145370      [ * ]      01/09/00

N290SK     145474      [ * ]      07/20/01

N292SK     145488      [ * ]      08/16/01

N294SK     145497      [ * ]      08/28/01

N296SK     145514      [ * ]      10/25/01
</Table>

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                                   APPENDIX 2

                                  NEW EXHIBIT A

                                    EXHIBIT A
                              DELTA AIR LINES, INC.
                         FIRM AIRCRAFT DELIVERY SCHEDULE

<Table>
<Caption>
Aircraft   Delivery          Date of:
 Number     Model     Delivery    In-Service
--------   --------   ---------   ----------
<S>          <C>      <C>         <C>
DL-1         145       Oct-02      1-Nov-02
DL-2         145       Oct-02      1-Nov-02
DL-3         135       Nov-02      1-Dec-02
DL-4         145       Nov-02      1-Dec-02
DL-5         145       Dec-02      1-Jan-03
DL-6         135       Dec-02      1-Jan-03
DL-7         145       Jan-03      1-Feb-03
DL-8         135       Jan-03      1-Feb-03
DL-9         135       Feb-03      1-Mar-03
DL-10        145       Feb-03      1-Mar-03
DL-11        135       Mar-03      1-Apr-03
DL-12        145       Mar-03      1-Apr-03
DL-13        135       Apr-03      1-May-03
DL-14        135       Apr-03      1-may-03
DL-15        135       May-03      1-Jun-03
DL-16        135       May-03      1-Jun-03
DL-17        135       Jun-03      1-Jul-03
DL-18        135       Jun-03      1-Jul-03
DL-19        135       Jul-03      1-Aug-03
DL-20        135       Jul-03      1-Aug-03
DL-21        135       Aug-03      1-Sep-03
DL-22        135       Sep-03      1-Oct-03
DL-23        145      1-Apr-03     9-Apr-03
DL-24        145      6-Apr-03    22-Apr-03
DL-25        145      6-Apr-03    23-Apr-03
DL-26        145      6-Apr-03     4-May-03
DL-27        145      1-May-03    22-May-03
DL-28        145      1-May-03    22-May-03
DL-29        145      15-May-03    9-Jun-03
DL-30        145      15-May-03    9-Jun-03
</Table>

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<Table>
<S>          <C>      <C>         <C>
DL-31        145      1-Jun-03    14-Jun-03
DL-32        145      1-Jun-03    23-Jun-03
DL-33        145      15-Jun-03   23-Jun-03
DL-34        145      15-Jun-03   26-Jun-03
</Table>

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                                   APPENDIX 3

                                      [ * ]

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                                   APPENDIX 4

                                      [ * ]

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                                   APPENDIX 5

                               ADDITIONAL WARRANT


                             [See Exhibit 10.28(a)]


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