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[CALFEE, HALTER & GRISWOLD LLP LETTERHEAD]


                                                                     EXHIBIT 5.1

                                  June 6, 2001

Hickok Incorporated
10514 Dupont Avenue
Cleveland, Ohio  44108

         We are familiar with the proceedings taken and proposed to be taken by
Hickok Incorporated, an Ohio corporation (the "Company"), with respect to
121,000 Class A Common Shares, $1.00 par value (the "Shares"), of the Company to
be offered and sold from time to time pursuant to the Company's 2000 Key
Employees Stock Option Plan and the Company's 2000 Outside Directors Stock
Option Plan (the "Plans"). As counsel for the Company, we have assisted in
preparing a Registration Statement on Form S-8 (the "Registration Statement") to
be filed by the Company with the Securities and Exchange Commission to effect
the registration of the Shares under the Securities Act of 1933, as amended.

         In this connection, we have examined such documents, records and
matters of law as we have deemed necessary or advisable to render the opinion
contained herein. Based upon our examination and inquiries, we are of the
opinion that the Shares are duly authorized and, when offered and sold pursuant
to the terms and conditions of the Plans, will be validly issued, fully paid and
nonassessable.

         Our opinion is limited solely to the laws of the State of Ohio.

         We consent to the filing of this opinion as Exhibit 5.1 to the
Registration Statement. We do not admit that we are in the category of persons
whose consent is required under Section 7 of the Act.

                                            Very truly yours,

                                            /s/ Calfee, Halter & Griswold LLP

                                            CALFEE, HALTER & GRISWOLD LLP