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                                                                    EXHIBIT 10.6

                             Confidential Agreement
                       By and Between AirNet Systems, Inc.
                             And Joel E. Biggerstaff


      This agreement is entered into by and between AirNet Systems, Inc.
("AirNet"), an Ohio corporation, and Joel E. Biggerstaff ("Biggerstaff").

      WHEREAS, AirNet desires to employ Biggerstaff in the positions of
President and Chief Operating Officer of AirNet;

      WHEREAS, Biggerstaff desires to accept the positions of President and
Chief Operating Officer of AirNet, effect August 16, 1999 ("Effective Employment
Date");

      WHEREAS, AirNet and Biggerstaff desire to enter into an agreement to
establish the rights and obligations of Biggerstaff and AirNet in such
employment relationship;

      NOW, THEREFORE, in consideration of the mutual promises and other good and
valuable consideration contained herein, the parties agree as follows:

     1.   Biggerstaff will satisfactorily discharge such duties as may be
          reasonably assigned to him in the capacity of President and Chief
          Operating Officer by AirNet's Chief Executive Officer.

     2.   Biggerstaff will be paid a Base Salary of $220,000 per year, payable
          bi-weekly. Biggerstaff's Base Salary subsequent to the first year
          following the Effective Employment Date may be adjusted annually by
          the Compensation Committee of the Board of Directors of AirNet
          Systems, Inc. ("AirNet Compensation Committee").

     3.   Biggerstaff will participate in the management incentive compensation
          system, which for on-plan performance (defined as 100% of agreed upon
          goals and objectives achieved) would pay Biggerstaff 70% of his Base
          Salary in the first year of employment, with a $30,000 guaranteed
          bonus for 1999 employment.

     4.   Incentive compensation targets subsequent to the first year may be
          adjusted annually by the AirNet Compensation Committee.

     5.   In the event of a change in control of AirNet resulting from either a
          substantial change in ownership or in senior management (as defined in
          a resolution by the AirNet Board of Directors), which results in
          Biggerstaff's involuntary termination of employment by AirNet or
          results in a material reduction in Biggerstaff's responsibilities
          without cause for a period of up to two years subsequent to
          Biggerstaff's Effective Employment Date, Biggerstaff will receive
          payment equal to one year of his then current Base Salary.

     6.   If Biggerstaff is involuntarily terminated by AirNet or its
          successor(s) for any reason other than fraud, bad faith, etc. for the
          period up to three years subsequent to the Effective Employment Date,
          AirNet will pay Biggerstaff an amount equal to one year of his then
          current Base Salary. Thereafter, if Biggerstaff is involuntarily
          terminated by AirNet or its successor(s) for any reason other than
          fraud, bad faith, etc., AirNet will pay Biggerstaff an amount equal to
          eighteen months of his then current Base Salary.

     7.   AirNet will award 80,000 AirNet stock options under the 1996 AirNet
          Incentive Stock Plan (1996 Plan), as amended, to Biggerstaff at the
          Effective Date of Employment. The options will be priced based on fair
          market value (as defined in the 1996 Plan) on the Effective Date of
          Employment and will vest 25% immediately and 25% annually over the
          following three years. If AirNet experiences a change in control (as
          defined in a resolution by the AirNet Board of Directors), unvested
          options will vest at the time of the change of control.

     8.   Biggerstaff will receive three weeks of paid vacation and other
          benefits customarily made available to AirNet officers and team
          members.

     9.   AirNet will pay all reasonable costs associated with relocating
          Biggerstaff's family to Central Ohio.

     10.  Biggerstaff will be entitled to personal use of the AirNet aircraft at
          cost, when available.

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      IN WITNESS WHEREOF, the undersigned voluntarily and knowingly signed this
Agreement this 16th day of July, 1999.

      WITNESSED:

      /s/ Ann Mancuso                     /s/ Joel E. Biggerstaff
      ------------------------            ----------------------------
      Ann Mancuso                         Joel E. Biggerstaff



      IN WITNESS WHEREOF, the undersigned is a duly authorized officer of AirNet
Systems, Inc. and voluntarily and knowingly signed this Agreement this 16th day
of July, 1999.

      WITNESSED:                          AIRNET SYSTEMS, INC.

      /s/ Ann Mancuso                     /s/ Gerald G. Mercer
      ------------------------            ----------------------------
      Ann Mancuso                         Gerald G. Mercer
                                          Its CEO