Document:

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                                                                   EXHIBIT 10.29

                             DEMAND PROMISSORY NOTE
                             ----------------------
                               DATE: June 29, 2001
                               -------------------

Table 1: PARTIES AND TERMS

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(a) Secured Party:                         (c) Debtor:
Raytheon Aircraft Credit Corporation       Great Lakes Aviation, Ltd.
P.O.  Box 85                               1022 Airport Parkway
Wichita, Kansas 67201                      Cheyenne, WY 82001
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(b) RESERVED                               (d) Commencement Date: June 29, 2001
                                           (e) Principal Sum: $8,786,778.00
                                           (f) Principal sum payable on demand

         For good and valuable consideration, the receipt and sufficiency of
which is hereby acknowledged, Debtor unconditionally promises to pay on demand
to the order of Secured Party, or its assigns, the Principal Sum, as stated in
Table (e), together with accrued interest at the applicable Interest Rate
specified below and such other charges and fees as herein provided. This
Negotiable Promissory Note is sometimes hereinafter referred to as the
"Promissory Note" or "Agreement". The "Commencement Date" shall be June 29,
2001.

The Principal Sum and accrued interest shall be repaid by Debtor to Secured
Party in accordance with the terms and subject to the conditions specified
below:

1. Interest Rate. In addition to Debtor's repayment of the Principal Sum, Debtor
shall pay interest to Secured Party on the unpaid balance of the Principal Sum
at the fixed rate of 8% per annum payable monthly in arrears. However, should an
Event of Default occur, the interest rate shall increase to 11% per annum
effective as of the date of occurrence of the default, and the newly established
interest rate shall remain in effect until the entire principal balance and any
unpaid interest and late charges are paid in full.

The annual rate of interest applicable hereunder, as specified above, is
sometimes referred to herein as the "Interest Rate". All interest shall be
calculated on the basis of a 360-day year and actual days outstanding.
Notwithstanding anything set forth herein to the contrary, in no event shall the
Interest Rate payable hereunder be higher than the maximum amount permitted
under applicable law.

2. Payment of Principal and Interest. The Principal Sum shall be repaid by
Debtor to Secured Party within three (3) business days following the receipt by
Debtor of a written demand from Secured Party to the address set forth in Table
1(c) above. Accrued interest shall be paid in arrears at the applicable rate of
interest specified above, on a monthly basis, until the principal balance,
together with all accrued interest and late charges, is paid in full. Debtor's
first monthly interest payment shall be due and payable August 1, 2001. Each
subsequent monthly interest payment shall be paid by Debtor on the same date of
each succeeding calendar month. The final interest payment shall be due and
payable on the date the principal balance is paid in full.

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3. Repayment and Prepayment. The aforesaid payments of principal and interest
shall be made to Secured Party at its office in Wichita, Kansas. All payments of
interest shall be due and payable, without demand or notice to Debtor, in strict
accordance with the aforesaid monthly schedule of payments. Any payment due on a
non-business day may be made on the next succeeding business day. Debtor's
payments hereunder, when received, shall be applied first to the payment of any
late payment charges owed as of the date such payment is received by Secured
Party (if any), and the remainder of Debtor's payment shall be applied to
payment of accrued interest. Debtor may prepay the unpaid balance of the
Principal Sum in part or in fill at any time and without any penalty.

4. Late Payment Charge. In the event Debtor is more than ten (10) days late in
making any payment due hereunder as specified above, a late payment charge in an
amount equal to three percent (3%) of the amount of the delayed payment shall be
assessed against Debtor and added to the amount of the delayed payment due
hereunder for the purpose of defraying Secured Party's expenses incident to
handling the delinquent payment. Any late payment charge assessed against Debtor
shall be immediately dire and payable to Secured Party. The late payment charge
shall be in addition to, and not in lieu of, any other remedy provided to
Secured Party in this Agreement for default by Debtor.

5. Secured Transaction. To secure the payment of Debtor's obligation hereunder
and 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 obligation or indebtedness, Debtor has previously executed a
Security Agreement, including amendments, granting to Secured Party a security
interest in all of the air carrier aircraft engines, propellers, appliances,
spare parts, avionics, accessories, instruments, rotables, equipment (including
ground support equipment), subassemblies, tools, kits, consumables, components
and related items for installation in or use in connection with Debtor's
airplanes, including, but not limited to, Debtor's Embraer Air Model EBB-120
Brasilia airplanes and Beechcraft Model 1900 type airplanes which Debtor owns or
leases. The aforementioned security agreement and amendments shall hereinafter
be collective referred to as the 'Security Agreement." The above-mentioned
property is hereinafter collectively referred to (as appropriate within the
context of this Agreement) as the "Collateral." Contemporaneously with the
execution of this Promissory Note, Debtor shall execute an amendment to the
Security Agreement granting to the Secured Party a security interest in all
Collateral described therein effective as of the date upon which Debtor first
granted a security interest to the Secured Party.

6. Purpose of Loan. Debtor warrants and represents to Secured Party that this
loan is for business, commercial or agricultural purposes and not primarily for
personal, family or household purposes.

7. Debtor's Default. The parties agree that the occurrence of any of the
following events shall constitute an "Event of Default":

         (a) Debtor's failure to make any timely payment of either principal,
         interest, late payment charges or any other amount required to be paid
         hereunder, or Debtor's failure to pay any amount required under any
         other promissory note, security agreement or lease

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         agreement between Debtor and Secured Party, if such failure continues
         for a period often (10) days beyond the due date of such payment;

         (b) Debtor's failure to perform any promise, agreement, obligation,
         warranty or covenant made by it herein or in the Security Agreements if
         such failure continues for a period of thirty (30) days after Secured
         Party has given Debtor notice of such failure;

         (c) Debtor's failure to maintain the insurance coverage as specified in
         the Security Agreement;

         (d) any material misrepresentation made by Debtor to Secured Party in
         connection with this Agreement;

         (e) entry of a money judgment against Debtor, if such judgment is
         nonappealable and remains undischarged or unstayed for a period in
         excess of sixty (60) days;

         (f) dissolution, termination of existence, insolvency, business
         failure, inability to pay debts as they mature, assignment for the
         benefit of creditors, or the commencement, with respect to Debtor, of
         any proceedings (either voluntary or involuntary) under any bankruptcy
         or insolvency laws;

         (g) appointment of a receiver of any material part or all of Debtor's
         assets if such appointment or proceeding continues for a period of more
         than sixty (60) days;

         (h) Debtor entering into any transaction, without the prior written
         consent of Secured Party, whereby all or substantially all of Debtor's
         undertakings, property and assets would become the property of any
         other company, whether by way of reconstruction, reorganization,
         consolidation, amalgamation, merger, transfer, sale or otherwise;

         (i) default in the payment by Debtor of any indebtedness for borrowed
         money owed to any creditor resulting in the acceleration of a material
         amount of indebtedness that would reasonably justify Secured Party in
         deeming itself insecure;

         (j) the prospect of payment, performance or realization of the
         Collateral, in the opinion of Secured Party, is or become significantly
         impaired; or

         (k) Debtor (or its Permitted Lessee) ceasing to be licensed pursuant to
         U.S. law to operate a commercial air service;

Should an Event of Default occur, Secured Party may employ all remedies allowed
by law, including declaring all indebtedness owed hereunder, as well as any
other indebtedness or liability of Debtor owed to Secured Party, immediately due
and payable. Additionally, Secured Party may require Debtor to assemble the
Collateral and make it available to Secured Party at a place to be designated by
Secured Party which is reasonably convenient to both parties. The requirements
of the Kansas Uniform Commercial Code for reasonable notification to Debtor of
the time and place of any proposed public sale of the Collateral or of the time
after which any private sale or other intended disposition of the Collateral is
to be made shall be met if such notice is mailed, postage prepaid, to Debtor's
address, as specified herein, at least ten (10) days

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before the time of the sale or disposition. After deduction of all reasonable
expenses incurred in realizing on Secured Party's security interest, and after
the payment of all principal, interest and late payment charges due under this
Agreement, the balance of the proceeds of sale, if any, may be applied by
Secured Party to the payment of any or all other indebtedness which Debtor owes
Secured Party, regardless of whether such indebtedness is due or not. Debtor
shall be liable for any deficiency in its financial obligation under this
Agreement after application of such proceeds. Debtor agrees to pay the
reasonable attorneys' fees incurred by Secured Party to repossess the Collateral
as well as the attorneys' fees incurred in pursuing and collecting any
deficiency. If, after a default by Debtor, the Collateral is returned to or
recovered by Secured Party, Debtor agrees that Secured Party may fly or
otherwise move the Collateral for demonstration and other purposes reasonably
related to a proposed public or private sale or other disposition of the
Collateral.

8. Obligation to Make Payments. Debtor acknowledges and agrees that its
obligation to make all payments due and owing under the provisions hereof shall
be absolute and unconditional and to the extent permitted by applicable law
shall not be affected by any circumstance whatsoever, including, without
limitation (a) any setoff, counterclaim, defense or other right which Debtor may
have against Secured Party or any other person or entity for any reason
whatsoever; (b) any defect in the title, airworthiness, eligibility for
registration under any statute, condition, design, operation or fitness for use
of, or any damage to or loss or destruction of Collateral identified in Section
5, or any interference, interruption or cessation in or prohibition of the use
or possession thereof by Debtor for any reason whatsoever, including, without
limitation, any such interference, interruption, cessation or prohibition
resulting from the act of any governmental authority; (c) any liens or rights of
others with respect to the Collateral; (d) the invalidity or unenforceability or
lack of due authorization of this Agreement or any lack of right, power or
authority of Debtor or Secured Party to enter into this Agreement; (e) any
insolvency, bankruptcy, reorganization or similar proceedings by or against
Debtor or any other person or entity; or (I) any other cause whether similar or
dissimilar to the foregoing, any present or future law notwithstanding, it being
the intention of the parties hereto that all payments being payable by Debtor
hereunder shall continue to be payable in all events in the manner and at the
time provided herein. Such payments shall not be subject to any abatement,
setoff or reduction for any reason whatsoever, including any present or future
claims by Debtor against Secured Party under this Agreement or otherwise. To the
extent permitted by applicable law, Debtor hereby waives any rights which it may
now have or which may be conferred upon it, by statute or otherwise, to
terminate, cancel, quit or surrender this Agreement except in accordance with
the terms hereof.

9. Waivers. Debtor hereby waives any requirements pertaining to presentment,
demand for payment, notice of dishonor, and all other notices or demands in
connection with the delivery, acceptance, performance, default or endorsement of
this Promissory Note. No waiver of any covenant, warranty or condition of this
Agreement, nor of any breach or default hereunder, shall be effective for any
purpose whatsoever unless such waiver is in writing and signed by an officer of
Secured Party. It is expressly agreed that Secured Party's waiver of any breach
or default by Debtor shall constitute a waiver only as to such particular breach
or default and not a waiver of any future breach or default.

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10. Legal, Valid, Binding and Enforceable Obligation. Debtor represents and
warrants to Secured Party that this Promissory Note, upon execution and
delivery, will constitute the legal, valid and binding obligation of Debtor and
shall be enforceable in accordance with its terms. Debtor agrees to furnish
Secured Party, if requested, with written legal opinions, satisfactory in form
and substance to Secured Party, verifying the aforesaid representation and
warranty.

11. Changes of Address. Debtor shall immediately notify Secured Party in writing
of any change of address from that shown in Table 1(c) in this Agreement.

12. GOVERNING LAW AND FORUM CHOICE. THIS AGREEMENT WAS MADE AND ENTERED INTO IN
THE STATE OF KANSAS AND THE LAW GOVERNING THIS TRANSACTION SHALL BE THAT OF THE
STATE OF KANSAS AS IT MAY FROM TIME TO TIME EXIST. THE LAW OF THE STATE OF
KANSAS SHALL APPLY TO ANY AND ALL MATTERS ARISING FROM OR RELATED TO THIS
AGREEMENT AND TRANSACTION, INCLUDING ANY ACTIONS UNDERTAKEN BY SECURED PARTY
SHOULD AN "EVENT OF DEFAULT" OCCUR. SUCH AS AN ACTION TO OBTAIN POSSESSION OF
AND FORECLOSE UPON THE COLLATERAL, AND ALL OTHER REMEDIES WHICH MAY BE AVAILABLE
INCLUDING SEEKING A DEFICIENCY JUDGMENT AGAINST DEBTOR. THE PARTIES AGREE THAT
ANY LEGAL PROCEEDING BASED UPON THE PROVISIONS OF THIS AGREEMENT SHALL BE
BROUGHT EXCLUSIVELY IN EITHER THE UNITED STATES DISTRICT COURT FOR THE DISTRICT
OF KANSAS AT WICHITA, KANSAS, OR IN THE EIGHTEENTH JUDICIAL DISTRICT COURT OF
SEDGWICK COUNTY, KANSAS. TO THE EXCLUSION OF ALL OTHER COURTS AND TRIBUNALS.
NOTWITHSTANDING THE ABOVE, IN THE EVENT AN "EVENT OF DEFAULT" SHOULD OCCUR.
SECURED PARTY (AT ITS SOLE OPTION) MAY INSTITUTE A LEGAL PROCEEDING IN ANY
JURISDICTION AS MAY BE APPROPRIATE IN ORDER FOR SECURED PARTY TO OBTAIN
POSSESSION OF AND FORECLOSE UPON THE COLLATERAL. THE PARTIES HEREBY CONSENT AND
AGREE TO BE SUBJECT TO THE JURISDICTION OF THE AFORESAID COURTS IN SUCH
PROCEEDINGS.

13. Enforceability. The provisions of this Agreement shall be severable and, if
any provisions are for any reason determined to be invalid, void or
unenforceable, in whole or in part, the remaining provisions shall remain in
full force and effect; provided that the purpose of the remaining valid,
effective and enforceable provisions is not frustrated; and provided further
that no party is substantially and materially prejudiced thereby.

14. Assignability. Secured Party shall have the absolute right to assign,
transfer or sell any of its rights under this Promissory Note to any party of
its choosing. If under any assignment the Assignor (Secured Party) shall
continue to be the party for collection of Debtor's monthly payments of interest
owed hereunder, no Assignee may declare a default for non-payment of the monthly
payments or interfere in Debtor's peaceful possession of the Collateral for
non-payment of such monthly payments, so long as Debtor has not failed to pay
Assignor (Secured Party), when due, any monthly payment owed hereunder. Debtor
may not assign, or delegate any of its rights or obligations hereunder without
the prior written consent of Secured Party.

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15. Binding Agreement. All obligations of Debtor hereunder shall bind the heirs,
legal representatives, successors and assigns of Debtor. If there be more than
one Debtor hereunder, their liabilities shall be joint and several. All rights
of Secured Party hereunder shall inure to the benefit of its successors and
assigns.

16. Entire Agreement. This Agreement and the Security Agreement constitutes the
entire agreement between and among the parties with respect to the subject
matter hereof. There are no verbal understandings, agreements, representations
or warranties between the parties which are not expressly set forth herein. This
Agreement shall not be changed orally, but only in writing signed by the parties
hereto.

17. Notices. Any notice pertaining to this Agreement shall be deemed
sufficiently given if personally delivered or sent by registered or certified
mail, return receipt requested, to the party to whom said notice is to be given.
Notices sent by registered or certified mail shall be deemed given on the third
day after the date of postmark. Until changed by written notice given by either
party, the addresses of the parties shall be as stated in Table 1(a) and (c) of
the Agreement. The designated addresses of both parties must be located within
the United States of America.

         In witness of the foregoing, Debtor has caused its duly authorized
officer to execute and deliver this Agreement at Wichita, Kansas on the Date
herein stated.

                                         Great Lakes Aviation, Ltd.

                                         By: ___________________________________

                                         Name/Title:____________________________

                                         "Debtor"

STATE OF WYOMING  )
                  ) ss:
COUNTY OF LARAMIE )

This instrument was acknowledged before me on the 29th day of June, 2001, by
Douglas G. Voss who is the President of Great Lakes Aviation, Ltd., on behalf of
the corporation.

                                         Notary Public:  _______________________

                                         My Commission Expires: ________________

                                       6<PAGE>

                                                                   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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