Document:

PROMISSORY NOTE

$7,000,000                                                    February 7, 2000
                                                           (Date of Execution)

     FOR VALUE RECEIVED, ELECSYS CORPORATION, a Kansas corporation, AIRPORT
SYSTEMS INTERNATIONAL, INC., a Kansas corporation, and DCI, INC., a Kansas
corporation (collectively, the "Borrowers"), jointly and severally promise to
pay to the order of BANK OF AMERICA, N.A. (the "Bank") at its office located at
10000 College Boulevard, Overland Park, Kansas 66210, or at such other place as
the holder hereof may from time to time designate, the principal sum of UNITED
STATES SEVEN MILLION DOLLARS (U.S.$7,000,000), or so much thereof as shall have
been advanced by the Bank to the Borrowers under the Loan pursuant to the terms
of the Letter of Credit, Loan and Security Agreement dated as of February 7,
2000, by and between the Bank and the Borrowers (the "Loan Agreement"), with
interest thereon as provided below. Interest and principal shall be payable in
lawful money of the United States, which shall be legal tender in payment of all
debts and dues, public and private, at the time of payment, as follows:

     (a) interest on the unpaid principal balance at an annual rate, which is
equal to the fluctuating prime rate of interest established and declared by the
Bank from time to time (the "Prime Rate") plus one-half of one percent per annum
(0.5%), shall be due and payable on the first calendar day of each and every
month after the date hereof until the principal sum is paid in full; and

     (b) the entire balance of principal and accrued and unpaid interest shall
be due and payable, on August 7, 2001.

     The Prime Rate does not necessarily represent the lowest rate of interest
charged by the Bank to borrowers. The rate of interest charged under this Note
shall change on the first day of the calendar month following the month in which
any change in the Prime Rate is announced. Interest shall be charged based on a
360-day year factor applied to actual days elapsed.

     If any amount payable hereunder is not paid when due or payment is made in
funds which are not immediately available or any other Event of Default (as
defined in the Loan Agreement) has occurred and remains in existence, interest
on the entire principal amount hereof and any accrued and unpaid interest shall
be paid at the rate which is at all times equal to three percent (3%) per annum
in excess of the rate otherwise payable hereunder from the date due until such
amount shall be paid in full or until funds are immediately available or other
Event of Default has been cured, as the case may be.

     Amounts which are advanced to the Borrowers under the Loan Agreement and
then repaid by the Borrowers shall thereafter be available to be readvanced to
the Borrowers in accordance with the terms of the Loan Agreement. The fact that
the balance hereunder may be

<PAGE>

reduced to zero from time to time pursuant to the Loan Agreement will not affect
the continuing validity of this Note or the Loan Agreement, and the balance may
be increased to the stated principal amount after any such reduction to zero.

     The Borrowers may, at their option, prepay the principal balance hereof, in
whole or in part, at any time, without premium or penalty; provided that any
such prepayment is accompanied by a payment of all accrued and unpaid interest
on the amount so prepaid. As provided in the Loan Agreement, the principal
balance hereof must be immediately prepaid by the Borrowers, without premium or
penalty, from all Proceeds of the Export Receivables and Export Inventory (as
such terms are defined in the Loan Agreement) which are received by the
Borrowers or the Bank.

     All payments received hereunder shall be applied first, to any unpaid
costs, fees and expenses due under the Loan Agreement and the other Financing
Documents defined therein, second, to the payment of accrued and unpaid
interest, and finally, to the payment of outstanding principal, unless otherwise
agreed to by the Bank.

     This Promissory Note is the Note referred to in the Loan Agreement and is
secured by and subject to the provisions contained in the Loan Agreement.

     This Note is to be governed by, construed under and enforced in all
respects according to the laws of the State of Missouri. The Borrowers hereby
consent to the non-exclusive jurisdiction of the state and federal courts of the
State of Missouri in any action to enforce the provisions of this Note.

     The rights and remedies of the holder of this Note, as provided herein,
shall be cumulative and concurrent and may be pursued singularly, successively
or together at the sole discretion of the holder, and may be exercised as often
as occasion therefor shall occur, and the failure to exercise any such right or
remedy shall in no event be construed as a waiver or release of the same.

     In the event that any one or more of the provisions (or any part of any
provision) of this Note shall for any reason be held to be invalid, illegal or
unenforceable in any respect, or in the event that any one or more of the
provisions of this Note operates or would prospectively operate to invalidate
this Note, then and in either of those events, such provision or provisions only
shall be deemed null and void and shall not affect any other provisions (or
remaining part of the affected provision) of this Note and the remaining
provisions (or remaining part of the affected provision) of this Note shall
remain operative and in full force and effect and shall in no way be affected,
prejudiced or disturbed thereby.

     The Borrowers and any guarantors and endorsers hereof severally waive
presentment, protest and demand, notice of protest, notice of demand and of
dishonor and non-payment of this Note and expressly agree that this Note or any
payment hereunder may be extended from time to time without in any way affecting
the liability of the Borrowers and any guarantors and endorsers.

<PAGE>

     WITNESS the signature and seal of the Borrowers by their duly authorized
officers as of the day and year first above written.

WITNESS (OR ATTEST):                     ELCSYS CORPORATION, as a borrower

                                         By:                           (SEAL)
                                            ---------------------------
                                             Name:
                                                   --------------------
                                             Title:
                                                   --------------------

                                         AIRPORT SYSTEMS INTERNATIONAL, INC.

                                         By:                           (SEAL)
                                            ---------------------------
                                             Name:
                                                  ---------------------
                                             Title:
                                                   --------------------

                                         DCI, Inc.

                                         By:                           (SEAL)
                                            ---------------------------
                                             Name:
                                                  ---------------------
                                             Title:
                                                   --------------------Supplemental Agreement

      This Agreement is entered into this 28th day of February, 2001, by and
between Elecsys Corporation ("Corporation") and Keith Cowan ("Employee").

      WHEREAS, Corporation and Employee have heretofore entered into a certain
Employment Agreement pursuant to which Employee is entitled to a specified
salary for services rendered on behalf of Corporation; and

      WHEREAS, in lieu of cash compensation payable to Employee pursuant to said
Employment Agreement, the parties desire that Employee shall receive a specified
number of shares of Corporation's common stock, $.01 par value ("Common Stock"),
as hereinafter set forth.

      NOW, THEREFORE, in consideration of the mutual promises contained herein
and other valuable consideration the receipt of which is hereby acknowledged,
the parties agree as follows:

      1. As soon as administratively practicable following the date hereof,
Corporation shall issue for the benefit of Employee 16,667 shares of Common
Stock. The parties agree that the issuance of such shares shall be a substitute
for the first $25,000.00 of salary otherwise payable (after all applicable
withholding and other payroll deductions) to Employee for services rendered on
and after February 11, 2001. In the event Employee's employment with Corporation
is terminated prior to the date Employee has completed the services giving rise
to the payment hereunder, Employee agrees that he shall repay to Corporation an
amount, in cash or shares of Common Stock, equal to the difference between
$25,000.00 and Employee's net salary for the period commencing February 11, 2001
and ending on his date of termination.

      2. Employee acknowledges that Corporation will withhold all applicable
employment tax and other withholding obligations imposed in connection with the
issuance of Common Stock hereunder, and Employee authorizes Corporation or its
affiliates to make any withholding for taxes which Corporation or such
affiliates deems necessary or proper in connection therewith.

      3. Employee and Corporation agree that this Agreement supplements the
Employment Agreement by and between such parties and, except as set forth
herein, does not affect the rights, duties and obligations of the parties under
said Employment Agreement.

      4. The rights and obligations of Corporation under this Agreement shall
inure to the benefit of and shall be binding upon the successors and assigns of
Corporation. Employee may not assign any of her rights or delegate any of his
duties or obligations under this Agreement without Corporation's express written
consent.

      5. In the event any term or provision hereof shall be determined by a
court of competent jurisdiction or arbitrator to be unenforceable, the remainder
hereof shall survive and the unenforceable provision shall be reformed to form
an enforceable provision consistent with the intent of the parties as evidenced
in this Agreement.

      6. This Agreement and all disputes arising hereunder shall be subject to,
governed by and construed in accordance with the laws of the State of Kansas.
<PAGE>

      IN WITNESS WHEREOF, the parties have executed this Agreement as of the day
and year first written above.

                                    Elecsys Corporation ("Corporation")

                                    By:___________________________

                                   "Employee"

                                    ------------------------------

Source: [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00021-of-00352.parquet"}, [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00021-of-00352.parquet"}]]