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                                                                  EXHIBIT 10.cc

                                    RESTATED
                       AIRPORT SYSTEMS INTERNATIONAL, INC.
                             1991 STOCK OPTION PLAN


         1. Purposes of the Plan. The purposes of this Stock Option Plan are to
attract and retain the best available personnel for positions of substantial
responsibility, to provide additional incentive to the Employees and Consultants
of the Company and to promote the success of the Company's business.

         Options granted hereunder may be either Incentive Stock Options or
Nonstatutory Stock Options, at the discretion of the Board and as reflected in
the terms of the written option agreement.

         2. Definitions. As used herein, the following definitions shall apply:

         (a) "Board" shall mean the Committee, if one has been appointed, or the
Board of Directors of the Company, if no Committee is appointed.

         (b) "Code" shall mean the Internal Revenue Code of 1986, as amended.

         (c) "Common Stock" shall mean the Common Stock of the Company.

         (d) "Company" shall mean Airport Systems International, Inc., a Kansas
corporation.

         (e) "Committee" shall mean the Committee appointed by the Board of
Directors in accordance with paragraph (a) of Section 4 of the Plan, if one is
appointed.

         (f) "Consultant" shall mean any person who is engaged by the Company or
any subsidiary to render consulting services and is compensated for such
consulting services or any other person determined by the Board to have
performed services for or on behalf of the Company which merits the grant of an
Option, and any director of the Company whether compensated for such services or
not; provided that if and in the event the Company registers any class of any
equity security pursuant to Section 12 of the Securities Exchange Act of 1934,
as amended (the "Exchange Act"), the term Consultant shall thereafter not
include directors who are not compensated for their services or are paid only a
director's fee by the Company.

         (g) "Continuous Status as an Employee or Consultant" shall mean the
absence of any interruption or termination of service as an Employee or
Consultant. Continuous Status as an Employee or Consultant shall not be
considered interrupted in the case of sick leave, military leave, or any other
leave of absence approved by the Board; provided that such leave is for a period
of not




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more than 90 days or reemployment upon the expiration of such leave is
guaranteed by contract or statute.

         (h) "Employee" shall mean any person, including officers and directors,
employed by the Company or any Parent or Subsidiary of the Company. The payment
of a director's fee by the Company shall not be sufficient to constitute
"employment" by the Company.

         (i) "Incentive Stock Option" shall mean an Option intended to qualify
as an incentive stock option within the meaning of Section 422A of the Code.

         (j) "Nonstatutory Stock Option" shall mean an Option not intended to
qualify as an Incentive Stock Option.

         (k) "Option" shall mean a stock option granted pursuant to the Plan.

         (l) "Optioned Stock" shall mean the Common Stock subject to an Option.

         (m) "Optionee" shall mean an Employee or Consultant who receives an
Option.

         (n) "Parent" shall mean a "parent corporation", whether now or
hereafter existing, as defined in Section 425(e) of the Code.

         (o) "Plan" shall mean this Restated 1991 Stock Option Plan.

         (p) "Share" shall mean a share of the Common Stock, as adjusted in
accordance with Section 12 of the Plan.

         (q) "Subsidiary" shall mean a "subsidiary corporation", whether now or
hereafter existing, as defined in Section 425(f) of the Code.

         3. Stock Subject to the Plan. Subject to the provisions of Section 12
of the Plan, the maximum aggregate number of shares which may be optioned and
sold under the Plan is 375,000 shares of Common Stock. The Shares may be
authorized, but unissued, or reacquired Common Stock.

         If an Option should expire or become unexercisable for any reason
without having been exercised in full, the unpurchased Shares which were subject
thereto shall, unless the Plan shall have been terminated, become available for
future grant under the Plan. Notwithstanding any other provision of the Plan,
shares issued under the Plan and later repurchased by the Company shall become
available for future grant or sale under the Plan.



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         4. Administration of the Plan.

         (a) Procedure.  The Plan shall be administered by the Board of
Directors of the Company.

               (i) Subject to subparagraph (ii), the Board of Directors may
          appoint a Committee consisting of not less than two members of the
          Board of Directors to administer the Plan on behalf of the Board of
          Directors, subject to such terms and conditions as the Board of
          Directors may prescribe. Once appointed, the Committee shall continue
          to serve until otherwise directed by the Board of Directors. Members
          of the Board who are either eligible for Options or have been granted
          Options may vote on any matters affecting the administration of the
          Plan or the grant of any Options pursuant to the Plan, except that no
          such member shall act upon the granting of an Option to himself, but
          any such member may be counted in determining the existence of a
          quorum at any meeting of the Board during which action is taken with
          respect to the granting of Options to him.

               (ii) Notwithstanding the foregoing subparagraph (i), if in any
          event the Company registers any class of any equity security pursuant
          to Section 12 of the Exchange Act, from the effective date of such
          registration (the "Effective Date") until six months after the
          termination of such registration (the "Termination Date"), any grants
          of options to officers or directors shall only be made by the Board of
          Directors; provided, however, that if any of the members of the Board
          of Directors are eligible to participate in this Plan or any other
          stock option or other stock plan of the Company or any of its
          affiliates, or has been eligible at any time within the preceding
          year, any grants of options to officers or directors of the Company
          must be made by, or only in accordance with the recommendation of, a
          Committee consisting of two or more directors, appointed by the Board
          of Directors and having full authority to act in the matter, none of
          whom is eligible to participate in this Plan or any other stock option
          or other stock plan of the Company or any of its affiliates, or has
          been eligible at any time within the preceding year. Once appointed,
          the Committee shall continue to serve until otherwise directed by the
          Board of Directors.

               (iii) Subject to the foregoing subparagraphs (i) and (ii), from
          time to time the Board of Directors may increase the size of the
          Committee and appoint additional members thereof, remove members (with
          or without cause) and appoint new members in substitution therefor,
          fill vacancies however caused, or remove all members of the Committee
          and thereafter directly administer the Plan.

         (b) Powers of the Board. Subject to the provisions of the Plan, the
Board shall have the authority, in its discretion: (i) to grant Incentive Stock
Options or Nonstatutory Stock Options; (ii) to determine upon review of relevant
information and in accordance with Section 8(b) of the Plan, the fair market
value of the Common Stock; (iii) to determine the exercise price per share of
Options to be granted, which exercise price shall be determined in accordance
with Section 8(a) of the Plan; (iv) to determine the Employees or Consultants to
whom, and; the time or times at which, Options shall be granted and the number
of shares to be represented by each Option; (v) to interpret the Plan;


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(vi) to prescribe, amend and rescind rules and regulations relating to the Plan;
(vii) to determine the terms and provisions of each Option granted (which need
not be identical) and, with the consent of the holder thereof, modify or amend
each Option; (viii) to accelerate or defer (with the consent of the Optionee)
the exercise date of any Option, consistent with the provisions of Section 5 of
the Plan; (ix) to authorize any person to execute on behalf of the Company any
instrument required to effectuate the grant of an Option previously granted by
the Board; and (x) to make all other determinations deemed necessary or
advisable for the administration of the Plan.

         (c) Effect of Board's Decision. All decisions, determinations and
interpretations of the Board shall be final and binding on all Optionees and any
other holders of any Options granted under the Plan.

         5.  Eligibility.

         (a) Options may be granted only to Employees and Consultants. Incentive
Stock Options may be granted only to Employees. An Employee or Consultant who
has been granted an Option may, if he is otherwise eligible, be granted an
additional Option or Options.

         (b) To the extent that the aggregate fair market value of Common Stock
with respect to which Incentive Stock Options are exercisable for the first time
by any Optionee during any calendar year (under all plans of the Company or any
Parent or Subsidiary) exceeds $100,000, such Incentive Stock Options shall be
treated as Nonstatutory Stock Options.

         (c) Section 5(b) of the Plan shall apply only to an Incentive Stock
Option evidenced by an "Incentive Stock Option Agreement" which sets forth the
intention of the Company and the Optionee that such Option shall qualify as an
incentive stock option. Section 5(b) of the Plan shall not apply to any Option
evidenced by a "Nonstatutory Stock Option Agreement" which sets forth the
intention of the Company and the Optionee that such Option shall be a
Nonstatutory Stock Option.

         (d) The Plan shall not confer upon any Optionee any right with respect
to continuation of employment or consulting relationship with the Company, nor
shall it interfere in any way with his right or the Company's right to terminate
his employment or consulting relationship at any time.

         6. Term of Plan. The Plan shall become effective upon the earlier to
occur of its adoption by the Board of Directors or its approval by the
shareholders of the Company as described in Section 18 of the Plan. It shall
continue in effect for a term of ten (10) years unless sooner terminated under
Section 14 of the Plan.

         7. Term of Options. The term of each Incentive Stock Option shall be
ten (10) years from the date of grant thereof or such shorter term as may be
provided in the Incentive Stock Option Agreement. The term of each Option that
is not an Incentive Stock Option shall be determined by the Board and set forth
in the Option Agreement. However, in the case of an Incentive Stock Option



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granted to an Optionee who, at the time the Incentive Stock Option is granted,
owns stock representing more than ten percent (10%) of the voting power of all
classes of stock of the Company or any Parent or Subsidiary, the term of the
Incentive Stock Option shall be five (5) years from the date of grant thereof or
such shorter time may in the Incentive Stock Option Agreement.

         8.  Exercise Price and Consideration.

         (a) Exercise Price. The per Share exercise price for the Shares to be
issued pursuant to exercise of an Option shall be such price as is determined by
the Board, but shall be subject to the following:

               (i)  In the case of an Incentive Stock Option

                    (A) granted to an Employee who, at the time of the grant of
               such Incentive Stock Option, owns stock representing more than
               ten percent (10%) of the voting power of all classes of stock of
               the Company or, any Parent or Subsidiary, the per Share exercise
               price shall be no less than 110% of the fair market value per
               Share on the date of grant.

                    (B) granted to any other Employee, the per Share exercise
               price shall be no less than 100% of the fair market value per
               Share on the date of grant.

               (ii) in the case of an Option granted on or after the effective
          date of registration of any class of equity security of the Company
          pursuant to Section 12 of the Exchange Act and prior to six months
          after the termination of such registration, the per Share exercise
          price shall be no less than 100% of the fair market value per Share on
          the date of grant.

               (iii) In the case of Non-Statutory Stock Options, at any price
          per share determined by the Board.

         (b) Fair Market Value. The fair market value shall be determined by the
Board in its discretion; provided, however, that where there is a public market
for the Common Stock, the fair market value per Share shall be the mean of the
bid and asked prices (or the closing price per share if the Common Stock listed
on that National Association of Securities Dealers Automated Quotation
("NASDAQ") National Market System) of the Common Stock for the date of grant, as
reported in The Wall Street Journal (or, if not so reported, as otherwise
reported by the NASDAQ System) or, in the event the Common Stock is listed on a
stock exchange, the fair market value per Share shall be the closing price on
such exchange on the date of grant of the Option, as reported in The Wall Street
Journal.

         (c) Form of Consideration. The consideration to be paid for the Shares
to be issued upon exercise of an Option, including the method of payment, shall
be determined by the Board and may consist entirely of cash, check, other Shares
of Common Stock having a fair market value on the date


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of surrender equal to the aggregate exercise price of the Shares as to which
said option shall be exercised, or any combination of such methods of payment,
or such other consideration and method of payment for the issuance of Shares to
the extent permitted under K.S.A. Sections 17-6402, 17-6403 and 17-6407 of the
Kansas General Corporation Code. In making its determination as to the type of
consideration to accept, the Board shall consider if acceptance of such
consideration may be reasonably expected to benefit the Company.

         9.  Exercise of Option.

         (a) Procedure for Exercise Rights as a Shareholder. Any Option granted
hereunder shall be exercisable at such times and under such conditions as
determined by the Board, including performance criteria with respect to the
Company and/or the Optionee, and as shall be permissible under the terms of the
Plan.

         An Option may not be exercised for a fraction of a Share.

         An Option shall be deemed to be exercised when written notice of such
exercise in the form required by the Nonstatutory or Incentive Stock Option
Agreement has been given to the Company in accordance with the terms of the
Option by the person entitled to exercise the Option and full payment for the
Shares with respect to which the Option is exercised has been received by the
Company. Full payment may, as authorized by the Board, consist of any
consideration and method of payment allowable under Section 8(c) of the Plan.
Until. the issuance (as evidenced by the appropriate entry on the books of the
Company or of a duly authorized transfer agent of the Company) of the stock
certificate evidencing such Shares, no right to vote or receive dividends or any
other rights as a shareholder shall exist with respect to the Optioned Stock,
notwithstanding the exercise of the Option. The Company shall issue (or cause to
be issued) such stock certificate promptly upon exercise of the Option. No
adjustment will be made for a dividend or other right for which the record date
is prior to the date the stock certificate is issued, except as provided in
Section 12 of the Plan.

         Exercise of an Option in any manner shall result in a decrease in the
number of Shares which thereafter may be available, both for purposes of the
Plan and for purchase under the Option, by the number of Shares as to which the
Option is exercised.

         10. Certain Events Affecting Exercisability of Incentive Stock Options.

         (a) Termination of Status as an Employee or Consultant. With respect to
Incentive Stock Options, in the event of termination of an Optionee's Continuous
Status as an Employee or Consultant (as the case may be), such Optionee may, but
only within sixty (60) days (or such other period of time not exceeding three
(3) months as is determined by the Board, with such determination being made at
the time of grant of the Option) after such event of termination of an
Optionee's Continuous Status as an Employee or Consultant (as the case may be)
(but in no event later than the date of expiration of the term of such Incentive
Stock Option as set forth in the


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Incentive Stock Option Agreement), exercise his Incentive Stock Option to the
extent that he was entitled to exercise it at the date of such termination. To
the extent that he was not entitled to exercise the Incentive Stock Option at
the date of such termination, or if he does not exercise such Incentive Stock
Option (which he was entitled to exercise) within the time specified herein, the
Incentive Stock Option shall terminate.

         (b) Disability of Optionee. With respect to Incentive Stock Options,
notwithstanding the provision of Section 10(a) above, in the event of
termination of an Optionee's Continuous Status as an Employee or Consultant (as
the case may be) as a result of his total and permanent disability (as defined
in Section 22(e)(3) of the Code), he may, but only within six (6) months (or
such other period of time not exceeding twelve (12) months as is determined by
the Board, with such determination being made at the time of grant of the
Incentive Stock Option) from the date of termination (but in no event later than
the date of expiration of the term of such Incentive Stock Option as set forth
in the Incentive Stock Option Agreement), exercise his Incentive Stock Option to
the extent he was entitled to exercise it at the date of such termination. To
the extent that he was not entitled to exercise the Incentive Stock Option at
the date of termination, or if he does not exercise such Incentive Stock Option
(which he was entitled to exercise) within the time specified herein, the
Incentive Stock Option shall terminate.

         (c) Death of Optionee. With respect to Incentive Stock Options, in the
event of the death of an Optionee:

               (i) who is at the time of his death an Employee or Consultant of
          the Company and who shall have been in Continuous Status as an
          Employee or Consultant since the date of grant of the Incentive Stock
          Option, the Incentive Stock Option may be exercised, at any time
          within nine (9) months following the date of death (but in no event
          later than the date of expiration of the term of such Incentive Stock
          Option as set forth in the Incentive Stock Option Agreement), by the
          Optionee's estate or by a person who acquired the right to exercise
          the Incentive Stock Option by bequest or inheritance, but only to the
          extent of the right to exercise that would have accrued had the
          Optionee continued living and remained in Continuous Status as an
          Employee or Consultant six (6) months after the date of death, subject
          to the limitation set forth in Section 5(b); or

               (ii) which occurs within thirty (30) days (or such other period
          of time not exceeding three (3) months as is determined by the Board,
          with such determination being made at the time of grant of the
          Incentive Stock Option) after the termination of Continuous Status as
          an Employee or Consultant, the Incentive Stock Option may be
          exercised, at any time within nine (9) months following the date of
          death (but in no event later than the date of expiration of the term
          of such Incentive Stock Option as set forth in the Incentive Stock
          Option Agreement), by the Optionee's estate or by a person who
          acquired the right to exercise the Incentive Stock Option by bequest
          or inheritance, but only to the extent of the right to exercise that
          had accrued at the date of termination.


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         11. Non-Transferability of Options. The Option may not be sold,
pledged, assigned, hypothecated, transferred, or disposed of in any manner other
than by will or by the laws of descent or distribution and may be exercised,
during the lifetime of the Optionee, only by the Optionee.

         12. Adjustments Upon Changes in Capitalization or Merger. Subject to
any required action by the shareholders of the Company, the number of shares of
Common Stock covered by each outstanding Option, and the number of shares of
Common Stock which have been authorized for issuance under the Plan but as to
which no Options have yet been granted or which have been returned to the Plan
upon cancellation or expiration of an Option, as well as the price per share of
Common Stock covered by each such outstanding Option, shall be proportionately
adjusted for any increase or decrease in the number of issued shares of Common
Stock resulting from a stock split, reverse stock split, stock dividend,
combination or reclassification of the Common Stock, or any other increase or
decrease in the number of issued shares of Common Stock effected without receipt
of consideration by the Company; provided, however, that conversion of any
convertible securities of the Company shall not be deemed to have been effected
without receipt of consideration. Such adjustment shall be made by the Board,
whose determination in that respect shall be final, binding and conclusive.
Except as expressly provided herein, no issuance by the Company of shares of
stock of any class, or securities convertible into shares of stock of any class,
shall affect, and no adjustment by reason thereof shall be made with respect to,
the number or price of shares of Common Stock subject to an Option.

         In the event of the proposed dissolution or liquidation of the Company,
the Option will terminate immediately prior to the consummation of such proposed
action, unless otherwise provided by the Board. The Board may, in the exercise
of its sole discretion in such instances, declare that any Option shall
terminate as of a date fixed by the Board and give each Optionee the right to
exercise his Option as to all or any part of the Optioned Stock, including
Shares as to which the Option would not otherwise be exercisable. In the event
of a proposed sale of all or substantially all of the assets of the Company, or
the merger of the Company with or into another corporation, the Option shall be
assumed or an equivalent option shall be substituted by such successor
corporation or a parent or subsidiary of such successor corporation. Unless the
option agreement granting an Option to an Optionee specifically provides
otherwise, in the event that such successor corporation refuses to assume the
Option or to substitute an equivalent option, the Board shall, in lieu of such
assumption or substitution, provide for the Optionee to have the right to
exercise the Option as to all of the Optioned Stock, including Shares as to
which the Option would not otherwise be exercisable. The Board shall give
written notice to each holder of an Option of the pendency of the sale of
substantially all of the assets of the Company, a merger involving the Company
or the dissolution or liquidation of the Company not less than ten days prior to
such transaction. If the Board makes an Option fully exercisable in lieu of
assumption or substitution in the event of a merger or sale of assets, the Board
shall notify the Optionee that the Option shall be fully exercisable for a
period of thirty (30) days from the date of such notice, and the Option will
terminate upon the expiration of such period.


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         13. Time of Granting Options. The date of grant of an Option shall, for
all purposes, be the date on which the Board makes the determination granting
such Option. Notice of the determination shall be given to each Employee or
Consultant to whom an Option is so granted within a reasonable time after the
date of such grant.

         14. Amendment and Termination of the Plan.

         (a) Amendment and Termination. The Board may amend or terminate the
Plan from time to time in such respects as the Board may deem advisable;
provided that, the following revisions or amendments shall require approval of
the shareholders of the Company in the manner described in Section 18 of the
Plan:

               (i) any increase in the number of Shares subject to the Plan,
          other than in connection with an adjustment under Section 12 of the
          Plan;

               (ii) any change in the designation of the class of persons
          eligible to be granted Options; or

               (iii) if the Company has a class of equity securities registered
          under Section 12 of the Exchange Act at the time of such revision or
          amendment, any material increase in the benefit accruing to
          participants under the Plan.

         (b) Shareholder Approval. If any amendment requiring shareholder
approval under Section 14(a) of the Plan is made subsequent to the first
registration of any class of equity securities by the Company under Section 12
of the Exchange Act, such shareholder approval shall be solicited as described
in Section 18 of the Plan.

         (c) Effect of Amendment or Termination. Any such amendment or
termination of the Plan shall not affect Options already granted and such
Options shall remain in full force and effect as if this Plan had not been
amended or terminated, unless mutually agreed otherwise between the Optionee and
the Board, which agreement must be in writing and signed by the Optionee and the
Company.

         15. Conditions Upon Issuance of Shares. Shares shall not be issued
pursuant to the exercise of an Option unless the exercise of such Option and the
issuance and delivery of such Shares pursuant thereto shall comply with all
relevant provisions of law, including, without limitation the Securities Act of
1933, as amended, the Exchange Act, the rules and regulations promulgated
thereunder, and the requirements of any stock exchange upon which the Shares may
then be listed, and shall be further subject to the approval of counsel for the
Company with respect to such compliance.

         As, a condition to the exercise of an Option, the Company may require
the person exercising such Option to represent and warrant at the time of any
such exercise that the Shares are being



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purchased only for investment and without any present intention to sell or
distribute such Shares if, in the opinion of counsel for the Company, such a
representation is required by any of the aforementioned relevant provisions of
law.

         16. Reservation of Shares. The Company, during the term of this Plan,
will at all times reserve and keep available such number of Shares as shall be
sufficient to satisfy the requirements of the Plan.

         The inability of the Company to obtain authority from any regulatory
body having jurisdiction, which authority is deemed by the Company's counsel to
be necessary to the lawful issuance and sale of any Shares hereunder, shall
relieve the Company of any liability in respect of the failure to issue or sell
such Shares as to which such requisite authority shall not have been obtained.

         17. Option Agreement. Options shall be evidenced by written option
agreements in such form as the Board shall approve.

         18. Shareholder Approval.

         (a) Continuance of the Plan shall be subject to approval by the
shareholders of the Company within twelve (12) months before or after the date
the Plan is adopted. If such shareholder approval is obtained at a duly held
shareholders' meeting, it must be obtained by the affirmative vote of the
holders of a majority of the outstanding shares of the Company, or if such
shareholder approval is obtained by written consent, it must be obtained by the
unanimous written consent of all shareholders of the Company; provided, however,
that approval at a meeting or by written consent may be obtained by a lesser
degree of shareholder approval if the Board determines, in its discretion after
consultation with the Company's legal counsel, that such a lesser degree of
shareholder approval will comply with all applicable laws and will not adversely
affect the qualification of the Plan under Section 422A of the Code.

         (b) If and in the event that the Company registers any class of equity
securities pursuant to Section 12 of the Exchange Act, any required approval of
the shareholders of the Company obtained after such registration shall be
solicited substantially in accordance with Section 14(a) of the Exchange Act and
the rules and regulations promulgated thereunder.

         (c) If any required approval by the shareholders of the Plan itself or
of any amendment thereto is solicited at any time otherwise than in the manner
described in Section 18(b) hereof, then the Company shall, at or prior to the
first annual meeting of shareholders held subsequent to the later of (1) the
first registration of any class of equity securities of the Company under
Section 12 of the Exchange Act or (2) the granting of an Option hereunder to an
officer or director after such registration, do the following:


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                  (i) furnish in writing, to the holders entitled to vote for
         the Plan substantially the same information which would be required (if
         proxies to be voted with respect to approval or disapproval of the Plan
         or amendment were then being solicited) by the rules and regulations in
         effect under Section 14(a) of the Exchange Act at the time such
         information is furnished; and

                  (ii) file with, or mail for filing to, the Securities and
         Exchange Commission four copies of the written information referred to
         in subsection (i) hereof not later than the date on which such
         information is first sent or given to shareholders.

         19. Gender Reference. The words "he", "him" or "his" shall be deemed to
include the feminine and neuter gender of such words.

         Adopted by the Board of Directors of Airport Systems International,
Inc. on October 1, 1993, and approved by the stockholders on October 18, 1993.



                                         /S/ Thomas C. Cargin
                                         -----------------------------------
                                         Thomas C. Cargin, Secretary







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