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                                                                   EXHIBIT 10.30

                         AMENDMENT TO SECURITY AGREEMENT
                           Great Lakes Aviation, Ltd.


         THIS AMENDMENT TO SECURITY AGREEMENTS Great Lakes Aviation, Ltd. is
entered into as of June 29, 2001 (the "Agreement"), by and between Great Lakes
Aviation, Ltd. as debtor (the "Debtor"), and Raytheon Aircraft Credit
Corporation as secured party (the "Secured Party");

                                   WITNESSETH:

         WHEREAS, Debtor and Secured Party are parties to an existing security
agreement as previously amended from time to time which is described and defined
on Exhibit "A" attached hereto and referred to as the "Security Agreement";

         WHEREAS, the Security Agreement encumbers various aircraft parts and
other collateral collectively described herein as the "Collateral";

         WHEREAS, as of this date, Debtor has executed a new Promissory Note
(the "New Note") in the principal amount of Eight Million Seven Hundred
Eighty-Six Thousand Seven Hundred and Seventy-Eight and No/l00 Dollars
($8,786,778.00) in favor of Secured Party;

         WHEREAS, the parties, by this amendment, intend to include a current
listing of all Collateral relating to Debtor's obligations under the New Note as
well as any and all other indebtedness owed by Debtor to the Secured Party,
which Collateral shall be described and defined on Exhibit "B" attached hereto
at the locations indicated;

         WHEREAS, the parties intend by this instrument to amend the Security
Agreement as of June 29, 2001, to specifically reflect that the Security
Agreements collectively secure payment of the Debtor's obligations under the New
Note in addition to any and all other indebtedness owed by Debtor to Secured
Party (whether now existing or hereafter arising), as well as any renewals,
extensions or changes in the form of said obligations or indebtedness;

         NOW, THEREFORE, for good and valuable consideration, the receipt and
sufficiency of which is acknowledged, the parties hereto agree as follows:

1.       Debtor and Secured Party hereby amend and supplement the Security
         Agreements to include a current list of all Collateral, as well as all
         new locations and existing locations described in the Security
         Agreement, all as more fully described on Exhibit "B" hereto and to
         confirm that the Collateral maintained at all locations IS and HAS been
         subject to the lien of the Security Agreements.

2.       Debtor certifies that it remains an air carrier holding a certificate
         issued under 49 U.S.C.ss. 44705, and that the Collateral described on
         Exhibit "B" hereto is maintained by or on behalf of the Debtor at the
         locations (which now includes new locations) specified thereon. All of
         the Collateral will at all times and until installed or used (in the
         ordinary course of Debtor's business) in an aircraft belonging to or
         leased by debtor, be located and and stored at Debtor's facilities or
         hangars at the locations listed on Exhibit "B."

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         Debtor shall not warehouse, inventory or store any of the Collateral at
         any other location without first obtaining the written consent of
         Secured Party and without first executing and filing with the FAA
         Registry a certificate pursuant to applicable sections of the Code of
         Federal Regulations evidencing such change of location and such other
         documents as may be required by Secured Party;

3.       Debtor confirms that the Security Agreement secures payment of the
         Debtor's obligation under the New Note, dated June 29, 2001, in
         addition to any and all other indebtedness owed by Debtor to Secured
         Party (whether now existing or hereafter arising), as well as any
         renewals, extensions or changes in the form of said obligations or
         indebtedness, and the Debtor and Secured Party hereby amend the
         Security Agreement to reflect the same;

4.       Debtor and agent further request that the FAA record this amendment
         against the locations (which term now includes the new locations) and
         any Collateral remaining subject to the Security Agreements;

5.       The Security Agreement as previously amended from time to time remains
         in full force and effect.

         THIS AMENDMENT TO SECURITY AGREEMENT Great Lakes Aviation, Ltd. 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.

GREAT LAKES AVIATION, LTD.               RAYTHEON AIRCRAFT CREDIT
                                         CORPORATION

By: ______________________________       By: __________________________________
Print Name: ______________________       Print Name: __________________________
Title: ___________________________       Title: _______________________________

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