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                        MODIFICATION AND WAIVER AGREEMENT



         THIS MODIFICATION AND WAIVER AGREEMENT (the "Agreement") is made and
entered into as of the 3rd day of March, 1999 between AMERICAN AIRCARRIERS
SUPPORT, INCORPORATED (the "Borrower") and NATIONSBANK, N.A. (the "Bank").


                              STATEMENT OF PURPOSE

         The Borrower and the Bank are parties to a Loan Agreement dated July
13, 1998 (as heretofore amended, the "Loan Agreement"). The Bank has agreed to
further amend the Loan Agreement as provided herein.

         NOW, THEREFORE, in consideration of the premises and other good and
valuable consideration, the receipt and sufficiency of which are hereby
acknowledged by the parties hereto, each to the other, the parties do hereby
agree as follows:

         1. Amendment of Loan Agreement.

         (a) Section 1 of the Loan Agreement is amended by inserting the
following definitions in proper alphabetical order:

                  EBITDA. EBITDA means, for any period, (a) net income of the
         Borrower for such period plus (b) the sum of the following, to the
         extent deducted in the determination of net income: (i) interest
         expense, (ii) income and franchise taxes and (iii) amortization,
         depreciation and other non-cash charges (including amortization of good
         will and other intangible assets), all determined in conformity with
         GAAP.

                  Senior Funded Debt. Senior Funded Debt means, with respect to
         the Borrower at any date and without duplication, the sum of the
         following calculated in accordance with GAAP: (a) all liabilities,
         obligations and indebtedness for borrowed money (other than
         Subordinated Debt) including but not limited to obligations evidenced
         by bonds, debentures, notes or other similar instruments of the
         Borrower, (b) all obligations to pay the deferred purchase price of
         property or services of the Borrower, except trade payables arising in
         the ordinary course of business, (c) all obligations of the Borrower as
         lessee under capital leases, (d) all indebtedness of any other Person
         secured by a lien on any asset of the Borrower, (e) all contingent
         obligations of the Borrower, (f) all obligations, contingent or
         otherwise, of the Borrower relative to the face amount of letters of
         credit, whether or not drawn, and banker's acceptances issued for the
         account of the Borrower and (g) all obligations incurred by the
         Borrower pursuant to Hedging Agreements.


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                  Subordinated Debt. Subordinated Debt means all indebtedness of
         the Borrower, the repayment of which is subordinated to the obligations
         of the Borrower under this Agreement in form and manner satisfactory to
         the Bank.

         (b) Section 5.A(i) is hereby amended by deleting the same in its
entirety and inserting in lieu thereof the following:

                  Maintain maximum Senior Funded Debt (determined on a
         consolidated basis for the Borrower and its consolidated subsidiaries)
         plus Subordinated Debt to trailing four quarters EBITDA of less than
         4.0 to 1.0 at all times prior to June 1, 1999 and 3.50 to 1.0 at all
         times thereafter.

         2. Amendment of Acquisition Loan Notes. Commencement of the
amortization of the principal balance of the Borrower's Promissory Note dated
November 16, 1998 in the principal amount of $8,700,000 shall be deferred from
March 1, 1999 to May 1, 1999, and commencement of the amortization of the
principal balance of the Borrower's Promissory Note dated December 7, 1998 in
the principal amount of $4,300,000 shall be deferred from April 1, 1999 to June
1, 1999.

         3. Limited Amendment. This Agreement shall not be deemed (i) to be a
waiver of, or consent to, or a modification or amendment of, any other term or
condition of the Loan Agreement or (ii) to prejudice any right or rights which
the Bank may now have or may have in the future under or in connection with the
Loan Agreement or any other loan document or any of the instruments or
agreements referred to therein, as the same may be amended or modified from time
to time.

         4. Representations and Warranties of the Borrower. The Borrower
represents and warrants to the Bank as follows:

                  (a) The Borrower has no defenses, offsets or counterclaims
         against the Bank relating to the Loan Agreement, as modified by this
         Agreement; and

                  (b) The Borrower has full power and lawful authority to
         execute and perform this Agreement.

         5. Definitions. All capitalized terms used but not otherwise defined
herein shall have the respective meanings ascribed to them in the Loan
Agreement.

         6. Conflict of Terms. In the event of a conflict between the terms of
this Agreement and the Loan Agreement, the terms of this Agreement shall govern.

         7. Counterparts. This Agreement may be executed in separate
counterparts, and said counterparts taken together shall be deemed to constitute
one and the same instrument. An executed copy of this Agreement delivered by
telecopier shall be intended to have the same effect as an originally executed
copy of this Agreement.


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         IN WITNESS WHEREOF, the parties have caused this instrument to be
executed and delivered by their duly authorized officers on the day and year
first above written.

                                              AMERICAN AIRCARRIERS SUPPORT,
                                              INCORPORATED


                                              By:  Karl Brown
                                                 -------------------------
                                                  Name:
                                                       ----------------------
                                                  Title: CEO
                                                        ----------------------

                                              NATIONSBANK, N.A.

                                              By:  /s/ Paul Rehkow
                                                 -------------------------
                                                  Name:
                                                       ----------------------
                                                  Title: Vice President
                                                        ----------------------


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