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                                                                   EXHIBIT 10.24

April 11, 2003

BCC-APM-2003-SDN-004C

VIA E-MAIL, FACSIMILE & COURIER
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Great Lakes Aviation, Ltd.
1022 Airport Road
Cheyenne, Wyoming 82001
Attn:  James Glennon
       Chief Financial Officer

Dear Mr. Glennon:

Boeing Capital Corporation presents the following lease restructuring proposal
(this "Proposal") to Great Lakes Aviation, Ltd. based on the following summary
of principal terms and conditions in connection with the Master Lease Agreement
dated as of December 28, 1994, (as supplemented, the "Lease") between Lessor and
Lessee. The parties intend that a Settlement Agreement be entered into to
further document the terms and conditions of this lease restructuring proposal
(the "Settlement Agreement") and the Lease be amended in accordance with the
Settlement Agreement.

  1  Lessor:         Boeing Capital Corporation ("BCC") or any of its
                     affiliates, successors or assigns ("Lessor").

  2  Lessee:         Great Lakes Aviation, Ltd. ("Lessee"), a company
                     incorporated or organized under the laws of Iowa with its
                     principal offices located at Cheyenne, Wyoming.

  3  Equipment:      Two (2) used Embraer ("Manufacturer") model 120 passenger
                     airframes, bearing serial numbers 120.293 and 120.297,
                     respectively equipped with two (2) Pratt & Whitney model
                     PW118A or PW118B engines (the "Engines") (collectively,
                     together with all records, logs and manuals, and parts,
                     accessories and equipment thereon or attached thereto in
                     the possession of Lessee, each an "Aircraft" and
                     collectively the "Aircraft"). Each Airframe, Engine,
                     Propeller, auxiliary power unit ("APU"), landing gear, or
                     other part or accessory previously delivered to Lessee
                     under the Lease may be individually or collectively
                     referred to herein as the "Equipment".

  4  Effective Date: The Settlement Agreement shall be effective as of December
                     31, 2002

  5  Lease Term:     Term of Lease remains unchanged

  6  Lease Rental    All past and future Rental Payments shall be paid in
     Payments:       accordance with the provisions of Attachment A hereto and
                     the Lease amended accordingly.

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  7  Early Lease     Lessor shall have the right in its sole discretion to
     Termination:    terminate the Lease upon no less than 180 days written
                     notice. Lessee shall return the Aircraft in compliance with
                     the return conditions under the Lease on the scheduled
                     return date.

  8  Preferred       The Preferred Shares are to be callable with no dividend if
     Shares:         Lessor exercises its early termination option, except such
                     shares shall not be callable if an event of default has
                     occurred and is continuing.

                     The Preferred Shares are to be issued to Lessor by Lessee
                     in a form and amount (Four Million Five Hundred Thousand
                     Dollars) acceptable to Lessor.

  9  Maintenance     Within ten (10) days following the end of each calendar
     Reserves:       month during the Lease Term, commencing with the month
                     immediately following the month in which the effective date
                     of the Settlement Agreement occurs, through and including
                     the month in which this Lease is terminated or expires and
                     the Aircraft is returned to Lessor in accordance with the
                     terms of the Lease, Lessee will pay to Lessor maintenance
                     reserves ("Maintenance Reserves") based on the number of
                     hours/cycles flown by each Aircraft in the previous month
                     during the Lease Term. The final Maintenance Reserve
                     payment due on the last day of the Lease Term shall include
                     payment for time flown by each Aircraft during the then
                     current month. Maintenance Reserves will be divided into
                     separate categories and separately tracked to cover
                     anticipated scheduled maintenance to be performed on each
                     Airframe, each Engine, each Propeller, each landing gear
                     and each APU. Maintenance Reserve payments per Aircraft
                     will total * per flight hour based on a flight
                     hours-to-cycle ratio of 1:1 as follows:

                     Airframe (C check):                 * per flight hour
                     Engine No.1 (HSI & Overhaul):       * per flight hour
                     Engine No.2 (HSI & Overhaul):       * per flight hour
                     Propeller No. 1:                         * per flight
                     Propeller No. 2:                         * per flight
                     APU (overhaul):                     * per flight hour
                     Landing Gear (overhaul):            * per flight cycle

                     The Maintenance Reserve amounts are subject to reasonable
                     adjustment once each year by Lessor on the anniversary of
                     the effective date of the Settlement Agreement to reflect
                     each Aircraft's utilization, life between maintenance
                     inputs, the levels of industry costs for material and labor
                     related to such maintenance work and the balances of such
                     reserves then currently held compared to anticipated
                     expenses.

                     Upon completion of the specified reimbursable maintenance
                     and payment for such work by Lessee, Lessee will submit to
                     Lessor invoices and other applicable maintenance records
                     that are acceptable to Lessor. Lessor will reimburse Lessee
                     for the actual costs it incurs to complete such heavy
                     maintenance, refurbishment and/or overhauls performed
                     either in-house or by third-party maintenance providers as
                     approved by Lessor, up to the

                     ---------
                     *  Confidential material omitted and filed separately with
                        the Securities and Exchange Commission pursuant to a
                        request for confidential treatment

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                     actual amounts paid by Lessee and not previously reimbursed
                     for the applicable Maintenance Reserve category, provided
                     Lessee submits to Lessor detailed original invoices,
                     acceptable to Lessor, and if applicable, from a mutually
                     acceptable third-party maintenance provider, within 90 days
                     after the Lessee's completion of such work, or Lessee's
                     receipt of invoices from third-party maintenance providers.
                     If, after reimbursement for qualified maintenance, there is
                     excess money in the component's reserve fund, the Lessee
                     may abate future reserve payment for utilization of that
                     component for a period equal to the excess reserve amount
                     divided by the applicable Maintenance Reserve rate.

                     Upon expiry of the Lease Term, Lessor will retain all
                     Maintenance Reserves then held by Lessor unless Lessee
                     consummates the purchase of the Aircraft in accordance with
                     the Lease then Lessee shall be entitled to the balance of
                     the Maintenance Reserve fund.

                     If the Lessor exercises its right of early termination, and
                     Lessee returns the aircraft as per the conditions required
                     under the Lease, Lessor shall return to Lessee the balance
                     of the unapplied Maintenance Reserves based on status and
                     usage data.

  10 Insurance:      Provisions shall remain as set forth in the Lease except
                     that if the Lessee has acquired a Certificate of Insurance
                     from the Federal Aviation Administration under the
                     provisions of Amendment 7 Lessee will provide a copy of the
                     Certificate of Insurance to Lessor and verification that it
                     has notified the Federal Aviation Administration that there
                     are additional insured parties to be covered under the
                     Certificate of Insurance.

  11 Redelivery      Shall remain as set forth in the Lease unless otherwise
     Conditions:     amended to the mutual satisfaction of both parties.

  12 Tax Matters:    Provisions shall remain as set forth in the Lease.

  13 Net Lease:      The Lease will be net, whereby Lessee will be obligated to
                     pay all costs, charges, fees, expenses, imposts, duties and
                     taxes (including any and all trade, value-added, or
                     withholding taxes) associated with the use, possession,
                     control, maintenance, repair, lease, sublease, insurance,
                     storage or operation of the Aircraft except Lessor Taxes.

                     "Lessor Taxes" means:

                     (a)    Taxes imposed solely as a result of activities of
                            Lessor in the jurisdiction imposing the liability
                            unrelated to Lessor's dealings with Lessee or to the
                            transactions contemplated by this Proposal or the
                            operation of the Aircraft by Lessee; and

                     (b)    U.S. federal and/or state net income taxes imposed
                            on Lessor.

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  14 Documentation:  Documentation for this current transaction will be prepared
                     by Lessee and will be governed by the laws of the State of
                     New York, U.S.A. All documentation shall be in English.

  15 Transaction
     Expenses:       For the account of Lessee.

  16 Conditions
     Precedent:      The terms of this Proposal and obligation of Lessor to
                     close this transaction are subject to the following:

                     (a)    Receipt of Lessee's signature on this Proposal no
                            later than the close of business (Seattle time) on
                            April 11, 2003.

                     (b)    Approval of Lessor's Investment Committee no later
                            than the close of business (Seattle time) on Friday
                            April 11, 2003(the "Investment Committee").

                     (c)    In Lessor's reasonable opinion, no material adverse
                            change shall have occurred in Lessee's financial
                            condition or in the commercial aviation industry
                            from the date this transaction is approved by
                            Lessor's Investment Committee to execution of
                            documentation satisfactory in form and substance to
                            the Lessor.

                     (d)    Execution and delivery of transaction documentation
                            including the Settlement Agreement in form and
                            substance satisfactory to Lessor on or before April
                            30, 2003.

                     (e)    Neither Lessee nor any of its affiliates shall be in
                            default of its obligations under any agreement
                            between Lessor or any affiliate of Lessor in any
                            material respect.

                     (f)    Receipt of a legal opinion of outside counsel in
                            form and substance satisfactory to Lessor to cover
                            but not be limited to issuance of the Preferred
                            Shares.

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NOTE: This Proposal and the above terms are subject to the approval by the
Investment Committee. The Investment Committee may (i) approve the Proposal as
written, (ii) reject the Proposal, or (iii) approve the Proposal subject to
additional terms and conditions. If either (ii) or (iii) occurs, this Proposal
as originally written shall be null and void. Great Lakes Aviation, Ltd. shall
be informed of the decision of the Investment Committee and any additional
conditions or terms imposed by the Investment Committee.

This Proposal, and the information set forth herein, is the confidential and
proprietary business information of BCC and may not be disclosed to any third
party without the prior written consent of BCC.

This Proposal shall be governed by the laws of the State of New York.

This Proposal is a summary only and is not an exhaustive discussion of the
issues arising from the proposed transaction. If the terms and conditions of
this Proposal meet with your approval, please indicate your acceptance by
signing two copies of this Proposal in the space provided below and returning
one signed copy to the undersigned. If BCC has not received Lessee acceptance of
this Proposal by April 14, 2003 this Proposal shall expire without notice.

If you have any questions, please do not hesitate to call the undersigned at
(425) 393-0970.

Sincerely,

/s/ Scott Nicholson

Scott Nicholson
Special Credit Officer
Aircraft Financial Services
Boeing Capital Corporation

AGREED AND ACCEPTED:

Great Lakes Aviation, Ltd.

By:         /s/ Michael L. Tuinstra
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Its:       Treasurer
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Date:        April 11, 2003
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