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                                                                   Exhibit 10.10

                          FIRST AMENDMENT TO CODE SHARE
                          AND REVENUE SHARING AGREEMENT

This FIRST AMENDMENT TO CODE SHARE AND REVENUE SHARING AGREEMENT (this "First
Amendment") is dated to be effective the 27th day of April, 2001 (the "Effective
Date"), between AMERICA WEST AIRLINES, INC., a Delaware corporation ("AWA"), and
MESA AIRLINES, INC., a Nevada corporation ("MESA").

                                    RECITALS:

A. AWA and MESA have entered into a Code Share and Revenue Sharing Agreement,
entered into as of March 20, 2001, to be effective retroactive to February 1,
2001 (the "Code Share Agreement"), to provide scheduled air transportation
services as America West Express. All capitalized terms used herein but not
defined shall have the meaning given to such terms in the Code Share Agreement.

B. AWA and MESA desire to amend the Code Share Agreement to provide additional
time for MESA to execute the Aircraft Contract.

NOW, THEREFORE, in consideration of the recitals and for other good and valuable
consideration, the receipt and sufficiency of which are hereby acknowledged, AWA
and MESA agree as follows:

                                   AMENDMENTS

1. The parties agree that Paragraph 1 of the Code Share Agreement shall be
amended in its entirety as follows:

      Effectiveness. This Agreement replaces the Original Agreement effective
      upon the date (the "Effective Date") that MESA executes a binding
      agreement to acquire the CRJ Aircraft required to be provided by MESA
      pursuant to Section 2.2.2 of this Agreement (the "Aircraft Contract").
      MESA shall provide AWA with written notice of the date the Aircraft
      Contract is executed together with copies of the Aircraft Contract. On the
      date of execution of the Aircraft Contract, all of the terms and
      provisions of this Agreement shall be effective retroactive to the
      Contract Date. On the Effective Date, the Original Agreement shall be
      terminated in its entirety. All sums payable pursuant to Section 6 of the
      Original Agreement between the Contract Date and Effective Date shall be
      recalculated pursuant to the terms of Section 7 of this Agreement, and
      AWA, subject to the rights regarding disputed amounts contained in Section
      7.8, shall pay additional and undisputed sums payable within 30 days after
      receipt of a written invoice for such recalculation. Until the Effective
      Date, AWA and MESA shall continue to perform pursuant to the Original
      Agreement. If the Aircraft Contract is not executed by June 1, 2001, then
      this Agreement shall automatically terminate and the terms and conditions
      of the Original Agreement shall remain in full force and effect.
      Simultaneously with the execution of this Agreement, AWA and MESA shall
      enter into an amendment to the Original Agreement providing for the
      addition of 3 CRJs under the Original Agreement if this Agreement is
      terminated pursuant to this Section.
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      As of the Contract Date, AWA and MESA dispute certain amounts that are
      payable between AWA and MESA under the Original Agreement (the "Disputed
      Amounts"). MESA and AWA shall continue to work to resolve their respective
      obligations concerning the Disputed Amounts pursuant to the terms of the
      Original Agreement. This is a new and separate agreement from the Original
      Agreement. The terms of this Agreement shall not be used by either MESA or
      AWA to determine or interpret the respective payment obligations of the
      parties for the Disputed Amounts. The respective obligations for the
      Disputed Amounts and other matters and disputes arising under the Original
      Agreement prior to the Contract Date shall be resolved pursuant to the
      terms, covenants, rights and remedies of the Original Agreement, shall not
      affect the rights, duties and obligations of AWA or MESA under this
      Agreement and shall not permit AWA or MESA to exercise any remedies under
      this Agreement. The intent of AWA and MESA is to resolve any disputes
      concerning the Disputed Amounts or any other matters and disputes under
      the Original Agreement and not pursuant to this Agreement.

                                  MISCELLANEOUS

2. Effect. Except as otherwise set forth in this First Amendment, the Code Share
Agreement shall remain in full force and effect as originally set forth.

3. Counterparts. This First Amendment may be executed in counterparts, all of
which when taken together shall be one and the same document.

4. Entire Agreement: This First Amendment constitutes the entire agreement
between the parties with respect to the subject matter hereof and supersedes all
prior understandings with respect thereto.

     AWA:                                  AMERICA WEST AIRLINES, INC.,
                                           A Delaware corporation

                                           By: /S/ Andrew Nocella
                                               -------------------------------



     MESA:                                 MESA AIRLINES, INC.,
                                           A Nevada corporation

                                           By:  /S/ Jonathan Ornstein
                                               ---------------------------------
                                                    Jonathan G. Ornstein
                                                    Chief Executive Office