Exhibit 5


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                LETTERHEAD OF BLACKWELL SANDERS PEPER MARTIN LLP

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                                  June 12, 2001


Elecsys Corporation
11300 West 89th Street
Overland Park, KS  66214

Ladies and Gentlemen:

         We have acted as counsel to Elecsys Corporation, a Kansas corporation
(the "Company"), in connection with the registration on Form S-8 under the
Securities Act of 1933, as amended, of 475,000 shares of Common Stock of the
Company, $.01 par value per share (the "Common Stock"), issuable under the
Airport Systems International, Inc. 1991 Restated Stock Option Plan (the
"Plan").

         In connection with the foregoing, we have examined such documents,
corporate records and other instruments as we have deemed necessary or
appropriate in connection with this opinion. Based upon and subject to the
foregoing, we are of the opinion that when such shares of Common Stock have been
issued and sold by the Company in accordance with the terms of the Plan, such
shares will constitute legally issued, fully paid and non-assessable shares of
the Company.

         We consent to the filing of this opinion as an exhibit to the
registration statement pursuant to which such shares will be sold and to the
reference to us in such registration statement.

                                    Very truly yours,




                                    /s/ Blackwell Sanders Peper Martin LLP



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