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                                                                    Exhibit 10.4


                CONSIGNMENT, CANCELLATION AND PURCHASE AGREEMENT

         This agreement is made this 29th day of August, 1997 between Jet 
Aviation Trading, Inc. having its principal place of business at 15675 N.W.
15th Avenue, Miami, FL 33167, (hereinafter referred to as "CONSIGNEE") and Jet
Avionics Systems, Inc., having its principal place of business at 18181 N.E.
31st Court, Suite 1907, North Miami Beach, FL 33160 (hereinafter referred to as
the "OWNER").

                                   RECITALS:

         WHEREAS, OWNER and CONSIGNEE entered into a Consignment Agreement
dated October 1, 1996, (the "Consignment Agreement") whereby OWNER consigned to
CONSIGNEE that certain Inventory defined in the Consignment Agreement for sale
by Consignee for the benefit of OWNER and CONSIGNEE; and

         WHEREAS, OWNER and CONSIGNEE have determined that CONSIGNEE shall
purchase the remaining unsold Inventory from Owner, as set forth on Exhibit
"A", attached hereto under the terms and conditions set forth herein;

         NOW THEREFORE, in consideration of the mutual covenants herein
contained, the parties hereto agree as follows:

         1.       Purchase: CONSIGNEE shall purchase all remaining unsold
                  Inventory originally consigned to CONSIGNEE under the
                  Consignment Agreement held by it on the 31st day of August,
                  1997 (the "Closing Date").

         2.       Purchase Price: The purchase price ("Purchase Price") for the
                  payment of such purchased Inventory shall be $675,000.

         3.       Payment: Payment of the Purchase Price shall be as follows:

                  a.       $340,000 of the Purchase Price has already been paid
                           to OWNER in cash and equity in CONSIGNEE.

                  b.       CONSIGNEE shall apply the outstanding balance of
                           principal and accumulated interest of OWNER's
                           promissory note to CONSIGNEE in the original
                           principal amount of $175,000 dated October 1,1 996,
                           originally given for its subscription of shares of
                           stock of CONSIGNEE to the Purchase Price; and

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                  c.       The remainder of the Purchase Price shall be paid by
                           issuing shares of CONSIGNEE's common stock at the
                           rate of $2.00 of the Purchase Price for each share
                           of common stock of Consignee. Owner acknowledges
                           that such shares of common stock have not been
                           registered for sale under the laws of the United
                           States or any state. Owner agrees to execute a
                           Subscription Agreement in the form attached hereto
                           as Exhibit "B".

         4.       Title: At closing, OWNER will execute a Warranty Bill of Sale
                  transferring marketable title to all of the remaining
                  Inventory to CONSIGNEE free and clear of all liens, claims
                  and encumbrances whatsoever. Further, OWNER warrants that it
                  shall defend such title forever to CONSIGNEE and CONSIGNEE's
                  third party customers.

         5.       Taxes: Taxes imposed by any federal, state or local taxing
                  authority within the United States and payable as a result of
                  the sale of the Inventory shall be borne by OWNER.

         6.       Material Certification: OWNER certifies the following
                  to CONSIGNEE:

                  (a)      Each item of Inventory covered by this Agreement was
                           produced by a manufacturer holding an FAA Approved
                           Production Inspection System issued under FAR 21,
                           Sub Part F, or by a manufacturer holding an FAA
                           Production Certificate issued under FAR 21, Sub.
                           Part G. Each item of Inventory was manufactured by
                           the prime manufacturer or its approved
                           manufacturing/supplier source holding one of the
                           following agreements/approvals; (i) a Fixed Quantity
                           Licensee/Consignment Agreement, or; (ii) an FAA/PMA
                           Licensee Agreement, or; (iii) written approval for
                           Direct Ship Authority from the prime manufacturer.
                           None of the items of Inventory have been subjected
                           to severe stress or heat (as in major aircraft,
                           engine failure, accident or fire). Any part found
                           not to comply with the standards of this paragraph 6
                           may, at Consignee's option, either be returned to
                           Owner or disposed of in accordance with the
                           appropriate regulatory standards; and,

                  (b)      The Inventory shall be sold by OWNER in an "as is"
                           condition and OWNER makes no warranties, guarantees
                           or representations of any kind, either express or
                           implied, statutory or otherwise, except as set forth
                           herein, with respect to the Inventory or any other
                           equipment or parts delivered by OWNER to CONSIGNEE
                           hereunder including any items of Inventory
                           overhauled/repaired or recertified; and

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                  (c)      All serialized and non-serialized items of Inventory
                           (rotable, repairable and/or engine) will be
                           accompanied with traceability to a commercial
                           aviation regulated source.

                  (d)      Airworthiness release certificates, where
                           applicable, will identify the FAA repair station
                           number and the signature of the approving inspector,
                           as well as all other pertinent information.

         7.       Confidentiality: Each party agrees (except with the prior
                  written consent of the other party):

                  (a)      not to disclose details of this Agreement to any
                           third parties other than its financial and legal
                           advisers; and,

                  (b)      to maintain confidentiality of all information
                           exchanged between the parties, including pricing
                           information and other proprietary knowledge, held as
                           confidential between OWNER and OWNER's suppliers and
                           CONSIGNEE and CONSIGNEE's customers, and not to use
                           such for the benefit of any third party.

                  Such confidentiality shall survive the Term of this
                  Agreement.

         8.       Applicable Law: The provisions of this Agreement and all
                  rights and obligations hereunder shall be governed by and
                  construed in accordance with the laws of the State of
                  Florida. Both parties hereby agree that this Agreement shall
                  be deemed to have been made in the County of Dade, Florida,
                  and that any suit, action or proceeding arising out of or
                  relating to this Agreement may be instituted in any State or
                  Federal court having its situs within the County of Dade,
                  Florida and each party hereby waives the personal service of
                  any and all process and consent that all such service of
                  process may be made by certified mail, return receipt
                  requested, directed to the address set forth herein for each
                  party. Any such notice shall be effective and shall be deemed
                  to have been given when received at, or after refusal to
                  receive, at the addresses set forth herein or at such other
                  substitute addresses provided in accordance with this
                  Article.

         9.       Brokers and Finders: CONSIGNEE and OWNER each agree that
                  there are no third parties involved as brokers and finders in
                  this transaction. OWNER indemnifies CONSIGNEE from liability
                  for any fees, commissions or other claims made, including all
                  legal costs, due to such claims caused by the indemnifying
                  party.

         10.      Assignment: This Agreement shall not be assigned in whole or
                  in part by either party hereto without the prior written
                  consent of the other party.

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         11.      Notices: All notices or requests under this Agreement shall
                  be in writing and shall be deemed to have been adequately
                  given when received by the party to whom such notice or
                  request is given. Notices may be delivered personally, by
                  first class mail, postage prepaid, by reputable courier or by
                  facsimile transmission and shall be addressed as follows:

                           If to CONSIGNEE: Jet Aviation Trading, Inc.
                           15675 N.W. 15th Avenue
                           Miami, FL 33169
                           Fax (305) 624-2944

                           If to OWNER: Jet Avionics Systems, Inc.
                           18181 N.E. 31st Court, Suite 1907
                           North Miami, FL 33160
                           Fax (305) 933-1635

         or to such other address as either party may designate, from time to
         time, by written notice to the other party.

         12.      Alterations: This Agreement shall be effective only when duly
                  signed by both parties hereto. It contains the entire
                  understanding between the parties and may not be changed,
                  modified or altered, nor any of its provisions waived, except
                  by an agreement in writing signed by the parties hereto. All
                  prior agreements or understandings between the parties in
                  connection with the subject matter of this Agreement are
                  superseded hereby and the waiver of any term of condition
                  herein by either party shall not be deemed a waiver of any
                  subsequent term or condition hereof.

         13.      Exhibits: Any Exhibits to this Agreement or side letters or
                  referring to this Agreement and duly agreed to by both
                  parties in writing shall automatically become a part of this
                  Agreement and unless specifically stated otherwise, the
                  provisions of this Agreement shall prevail in the event of
                  any inconsistency.

         14.      Severability: In the event that any provision of this
                  Agreement is rendered void, invalid, or unenforceable in a
                  certain jurisdiction, then such provision (or part thereof)
                  may be severed from this Agreement without affecting the
                  remaining provisions hereof, as long as such severance does
                  not have a material adverse affect on the performance of this
                  Agreement.

         15.      Headings: The headings to the clauses of this Agreement are
                  for the purpose of reference only and in no way define, limit
                  or describe the scope of intent of this Agreement.

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         16.      Non-Exclusivility: The relationship of OWNER and CONSIGNEE
                  under this Agreement is non-exclusive. Both parties reserve
                  the right to enter into agreements with other parties for the
                  provision of similar or identical services at any time before
                  or after the Closing Date. Further, nothing herein shall
                  authorize either party to hold itself out as acting for or on
                  behalf of the other party.

         17.      Counterparts: This Agreement may be executed simultaneously
                  in two or more counterparts, each of which shall constitute
                  an original but all of which taken together shall constitute
                  one and the same instrument. A facsimile signature on any
                  counterpart hereto shall be deemed an original for all
                  purposes.

         IN WITNESS WHEREOF, the parties hereto by their duly authorized
officers have executed this Agreement as of the day and year first above
written.

                                  JET AVIATION TRADING, INC.

                                  BY:/s/ Joseph J. Nelson
                                     --------------------------------
     
                                  JET AVIONICS SYSTEMS, INC.
     
                                  BY:/s/ Sharon Taoz
                                     --------------------------------



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                                  BILL OF SALE

         FOR VALUABLE CONSIDERATION, receipt of which is here acknowledged, Jet
Avionics Systems, Inc. ("Seller") does hereby grant, bargain, sell, assign,
transfer and deliver to Jet Aviation Trading, Inc. ("Purchaser") all of
Seller's right, title, and interest in and to the goods and chattels which are
listed on Exhibit "A" attached to this bill of sale.

         TO HAVE AND TO HOLD unto the Purchaser, its successors and assigns
forever.

         And the Seller does, for itself, its successors, and assigns, covenant
to and with the Purchaser, its successors and assigns that the Seller is the
lawful owner of the said goods and chattels; that they are free from all
encumbrances; that the Seller has good right to sell the same aforesaid, and
that Seller will warrant and defend the transfer of the goods and chattels
hereby made, unto the Purchaser, its successors and assigns against the lawful
claims and demands of all persons whomsoever.

         IN WITNESS WHEREOF, the Seller has caused this document to be executed
in its name and its corporate seal affixed by its proper officers thereto duly
authorized this 29th day of August, 1997.


Signed, sealed and delivered              JET AVIONICS SYSTEMS, INC.
in the presence of:                       Seller:

/s/ Zvi Mosite                            /s/ Sharon Taoz
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Witness (Sign Name)                       Sharon Taoz, President

Zvi Mosite 
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(Print Name of Witness)