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                                                                Exhibit 10.13(a)



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                        PARTIAL ASSIGNMENT AND ASSUMPTION
                        OF PURCHASE AGREEMENT GCT-025/98
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This Partial Assignment and Assumption of Purchase Agreement GCT-025/98
("Agreement") dated April 19, 2002, is an agreement between SOLITAIR CORP.
("Assignor") a Delaware corporation with its principal place of business at
Greenwich, Connecticut and Republic Airways Holdings, Inc. ("Assignee"), a
Delaware corporation with its principal place of business at Indianapolis,
Indiana 46241, United States, and consented to by Embraer - Empresa Brasileira
de Aeronautica S.A. ("Embraer"), with its principal place of business at Sao
Jose dos Campos, Sao Paulo, Brazil, relating to Purchase Agreement GCT-025/98
(as amended prior to the date hereof, the "Purchase Agreement").

This Agreement constitutes an amendment and modification of the Purchase
Agreement, and it sets forth additional agreements of the Parties with respect
to the matters set forth in the Purchase Agreement. All terms defined in the
Purchase Agreement shall have the same meaning when used herein, and in case of
any conflict between this Agreement and the Purchase Agreement, this Agreement
shall govern.

WHEREAS,

Assignor is the "Buyer" under the Purchase Agreement and desires to assign to
Assignee all of its rights and obligations with respect to the twenty (20)
unexercised Option Aircraft, and seventeen additional option aircraft positions
that were connected to the Purchase Agreement (the "Assigned Aircraft"), and
Assignee is willing to accept such assignment on the terms and conditions of
this Agreement;

In connection with this assignment, Assignor will also assign to Assignee its
post-delivery rights under the Purchase Agreement with respect to (i) all
forty-eight (48) aircraft previously delivered to Chautauqua Airlines, Inc.
("Chautauqua") as operator (the "Delivered Aircraft") and (ii) any of the
Remaining Solitair Aircraft that are delivered to Chautauqua as operator; and

Assignor will retain its rights and obligations with respect to the five (5)
exercised Option Aircraft that have not been delivered as of the date of this
Agreement (the "Remaining Solitair Aircraft").

NOW, THEREFORE, for good and valuable consideration, receipt of which is hereby
acknowledged, Assignee and Assignor agree as follows:

1.       ASSIGNMENT AND ASSUMPTION

1.1.     The Assignor hereby irrevocably assigns, conveys, transfers and
         delegates to the Assignee:

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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.

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                  (a)      all its rights and obligations under the Purchase
                           Agreement and Letter Agreement DCT-026/98, dated as
                           of June 17, 1998 between Solitair and Embraer, as
                           amended (the "Letter Agreement"), in regard to the
                           Assigned Aircraft; and

                  (b)      all its remaining rights with respect to the
                           Delivered Aircraft under the Purchase Agreement and
                           Letter Agreement


         (the "Assigned Rights and Obligations"), subject to the terms and
         conditions herein. This assignment shall be effective as of the date
         provided below in Section 3 and the obligations of Assignor and
         Assignee hereunder shall be deemed to have begun on that date.

1.2.     The Assignee hereby irrevocably accepts the assignment, conveyance,
         transfer and delegation by the Assignor of the Assigned Rights and
         Obligations above and agrees to be bound by and perform all the
         obligations resulting from such assignment. The Assignee further
         undertakes to perform all obligations, undertakings and covenants in
         regard to the Assigned Rights and Obligations as if the Assignee had
         been an original party to the Purchase Agreement, and the Assignor
         shall have no liability to Embraer in regard to the Assigned Rights and
         Obligations; provided that, for the avoidance of doubt, nothing herein
         shall limit, reduce or otherwise affect Assignor's liability to Embraer
         under the Purchase Agreement or Letter Agreement for any events prior
         to the effective date of this Agreement.

1.3.     Assignor hereby agrees that promptly after delivery of each of the
         Remaining Solitair Aircraft, Assignor will assign to Assignee its
         remaining rights under the Purchase Agreement and Letter Agreement with
         respect to such Aircraft.

2. ASSIGNOR RETAINS CERTAIN RIGHTS AND OBLIGATIONS

2.1. All rights and obligations not expressly included in the partial assignment
described in clause 1.1. above are hereby retained by the Assignor, and the
Assignee shall have no rights or obligations with respect to such retained
rights. Notwithstanding anything to the contrary herein, Assignor shall remain
responsible for its obligations pursuant to Article 27 of the Purchase
Agreement.

3. SUBJECT TO EFFECTIVENESS OF AMENDED AND RESTATED PURCHASE AGREEMENT

This Agreement shall become effective at the time [*]


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* Confidential


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[*]

4. MISCELLANEOUS

All terms and conditions of the Purchase Agreement that have not been
specifically altered or modified hereunder shall remain in full force and effect
and time is of the essence under this Agreement.

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* Confidential


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IN WITNESS WHEREOF, the Parties have caused this Agreement to be duly executed
and delivered by their proper and duly authorized officers and to be effective
as of the day and year first above written.

SOLITAIR CORP.                               REPUBLIC AIRWAYS HOLDINGS, INC.


By: /s/ Kenneth A. Rubin                     By: /s/ Bryan Bedford
   --------------------------                   ----------------------------

Name: Kenneth A. Rubin                       Name: Bryan Bedford
     ------------------------                   ----------------------------

Title: Vice President                        Title: President
      -----------------------                      -------------------------



By: /s/ Frederick Simon
   --------------------------

Name: Frederick Simon
     ------------------------


Title: President
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Witness: /s/ Arthur Amron                    Witness: /s/ Robert H. Cooper
        ---------------------                        -----------------------

Name: Arthur Amron                           Name: Robert H. Cooper
     ------------------------                     --------------------------



Acknowledged and Agreed:

EMBRAER - Empresa Brasileira de Aeronautica S.A.

By: /s/ Frederico Fleury Curado
   -----------------------------

Name: Frederico Fleury Curado
     ---------------------------

Title: E.V.P. Airline Market
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By: /s/ Flavio Rimoli
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Name: Flavio Rimoli
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Title: Director of Contracts
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Witness: /s/ Fernando Bueno
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Name: Fernando Bueno
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