SIXTH AMENDMENT TO CREDIT AGREEMENT


                  This Sixth  Amendment  is made as of the 1st day of  February,
1997  by  and  between  FIELDS  AIRCRAFT  SPARES   INCORPORATED,   a  California
corporation (the  "Borrower"),  and NORWEST  BUSINESS CREDIT,  INC., a Minnesota
corporation (the "Lender").

                                    RECITALS

                  The  Borrower  and the Lender have entered into the Credit and
Security  Agreement  dated as of  February  9,  1995 and  amended  by the  First
Amendment to Credit  Agreement dated November 21, 1995, by the Second  Amendment
to Credit  Agreement  dated February 29, 1996, by the Third  Amendment to Credit
Agreement dated June 30, 1996, by the Fourth Amendment to Credit Agreement dated
August 16, 1996 and by the Fifth Amendment to Credit  Amendment dated January 1,
1997 (as amended, the "Credit Agreement").

                  The Borrower may request certain advances from the Lender from
time to time  pursuant  to the  Credit  Agreement,  and the Lender  may,  in its
discretion,  choose  to  make  loans  to the  Borrower  pursuant  to the  Credit
Agreement.  The Lender may demand repayment of the loans at any time pursuant to
the terms of the Credit Agreement.

                  The loan advances under the Credit  Agreement are evidenced by
the  Borrower's  demand  promissory  note dated as of February  9, 1995,  in the
maximum principal amount of Ten Million Dollars ($10,000,000) and payable to the
order of the Lender (the "Note").

                  All  indebtedness  of the  Borrower  to the  Lender is secured
pursuant to the terms of the Credit  Agreement and all other Security  Documents
as defined therein  (collectively,  the "Security  Documents") and is guaranteed
pursuant to the  unconditional  guaranties of the Corporate  Guarantors  defined
therein and is further  guaranteed  pursuant to the validity  guaranties  of the
Individual Validity Guarantors (collectively, the "Validity Guarantors").

                  The Borrower has requested that certain  amendments be made to
the Credit Agreement,  which the Lender is willing to make pursuant to the terms
and conditions set forth herein.

                  NOW,  THEREFORE,  in  consideration of the premises and of the
mutual covenants and agreements herein contained, it is agreed as follows:



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         1.       Definitions and Amendments.

                  (a) Terms used in this Sixth  Amendment  which are  defined in
         the Credit  Agreement shall have the same meanings as defined  therein,
         unless otherwise defined herein.

                  (b) The term "Net  Investment  Proceeds" is hereby  defined to
         mean the  proceeds  received by the Borrower  from any  advance,  loan,
         extension  of  credit  or  capital  contribution  to,  or any  sale  or
         commitment  to sell  any  stocks,  bonds,  notes,  debentures  or other
         securities  of or any other  investment  in,  the  Borrower  (each such
         transaction,  an "Investment"),  net of reasonable expenses incurred by
         the Borrower in connection with said Investment.

                  (c)      The definition of the term "Borrowing Base" is hereby
         amended   as   follows:  "Borrowing  Base"  means,  at  any  time   and
         subject  to  change from  time to time in the Lender's sole discretion,
         the lesser of:

                           (i) $6,100,000 provided,  however, that the Borrowing
                  Base (i) shall be  decreased  by the amount of Net  Investment
                  Proceeds received by the Borrower on or after February 1, 1997
                  on each day of receipt of any of said proceeds,  provided that
                  in any event the Borrowing  Base shall be decreased by no less
                  than  $450,000  on or before  March 31,  1997,  and (ii) shall
                  further be  decreased  by  $250,000 on the first day of April,
                  1997 and on the same day of each successive month thereafter;

                  or

                  (d)      the sum of:

                           (i) the lesser of (A) 75% of Eligible Accounts or (B)
                  $6,100,000;  provided,  however,  that such maximum  amount of
                  Eligible  Accounts  (i) shall be  reduced by the amount of Net
                  Investment  Proceeds  received  by the  Borrower  on or  after
                  February 1, 1997 on each day of receipt of any said  proceeds,
                  provided  that in any event  the  maximum  amount of  Eligible
                  Accounts  shall be  reduced  by no less  than  $450,000  on or
                  before  March 31, 1997,  and (ii) shall  further be reduced by
                  $250,000  on the first day of April,  1997 and on the same day
                  of each successive month thereafter; plus

                           (ii) the lesser of (A) 50% of Eligible  Inventory  or
                  (B) $5,800,000; provided, however, that such maximum amount of
                  Eligible  Inventory  shall be reduced by $100,000 on the first
                  day of  March,  1997 and on the  same  day of each  successive
                  month thereafter, plus


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                           (iii)    $250,000.
                  (e)      Section 2.12 Fees  is  hereby  amended  by adding the
                  following subsection (f) at the end thereof:

                           (f) The Borrower  agrees to pay to Lender daily a fee
                  in the  amount of $1,000 for each day  during  February,  1997
                  when the Borrowing  Base has not been reduced upon the receipt
                  of Net Investment Proceeds to or below $5,900,000 and for each
                  day during March,  1997 when the  Borrowing  Base has not been
                  reduced  upon the  receipt of Net  Investment  Proceeds  to or
                  below $5,650,000.  Such daily fee shall be payable  commencing
                  on February 3, 1997 and  continuing  until the Borrowing  Base
                  has been so reduced during February 1997 and commencing  March
                  1, 1997 until the  Borrowing  Base has been so reduced  during
                  March 1997.

                  (f)      Section 6.10  Lockbox;  Collateral  Account is hereby
                  amended  by  adding  the  following  subsection (c) at the end
                  thereof:

                           (c) The Borrower  agrees to deposit in the Collateral
                  Account or, at the Lender's  option,  to deliver to the Lender
                  all Net  Investment  Proceeds  which the Borrower may receive,
                  immediately upon receipt thereof, in the form received, except
                  for the Borrower's  endorsement when deemed  necessary.  Until
                  delivered  to  the  Lender  or  deposited  in  the  Collateral
                  Account,  no Net Investment  Proceeds shall be commingled with
                  any  other  funds  or  property  of  the  Borrower.   All  Net
                  Investment  Proceeds deposited in the Collateral Account shall
                  be subject  to the  provisions  set forth in  Section  6.10(b)
                  above   applicable  to  any  other  amount  deposited  in  the
                  Collateral  Account.   Upon  receipt  of  any  Net  Investment
                  Proceeds,  the Borrower shall promptly provide a report to the
                  Lender  describing the terms of the Investment  giving rise to
                  such Net  Investment  Proceeds and itemizing all expenses paid
                  out of the  proceeds of such  Investment,  together  with such
                  further  information  as the  Lender  may  in  its  discretion
                  require.

         2.       No Other Amendments.  Except  as  explicitly  amended  by this
Sixth  Amendment,  all of the terms and conditions of the Credit Agreement shall
remain in full force and effect and shall apply to any advance thereunder.

         3.       Conditions.  This  Sixth  Amendment  shall  be  effective (the
"Effective  Date") upon  receipt by the Lender of an executed  original  hereof,
together with each of the  following,  each in substance and form  acceptable to
the Lender in its sole discretion:

                  (a) The Acknowledgement and Agreement of Corporate  Guarantors
         and the Acknowledgment  and Agreement of Validity  Guarantors set forth
         at the  end of  this  Sixth  Amendment,  duly  executed  by each of the
         Corporate Guarantors and Individual Validity Guarantors, respectively.

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                  (b) Supplemental  Secretary's  Certificate  certifying (i) the
         resolutions  of the board of directors of the  Borrower  approving  the
         execution and delivery of this Sixth  Amendment and the  performance by
         the Borrower of its obligation under the Sixth Amendment and the Credit
         Agreement as amended  hereby,  (ii) that the Articles of  Incorporation
         and the Bylaws of the Borrower  which were  certified  and delivered to
         the Lender  pursuant to the  Certificate  of Secretary  Borrower  dated
         February  9, 1995  continue  in full force and effect and have not been
         altered,  amended or revised,  and (iii) the signatures of the officers
         and agents of the Borrower authorized to execute and deliver this Sixth
         Amendment and other instruments, agreements and certificates, including
         Advance requests, on behalf of the Borrower.

                  (c)      Payment of the fees and  expenses required to be paid
         by the Borrower under Paragraph 8.

                  (d)      Such  other  documents  as  the  Lender  in  its sole
         discretion may require.

         4.       Representations and Warranties.

         The Borrower hereby represents and warrants to the Lender as follows:

                  (a) The  Borrower  has all  requisite  power and  authority to
         execute  this Sixth  Amendment  and to perform  all of its  obligations
         hereunder and under the Credit  Agreement as amended  hereby,  and this
         Sixth  Amendment  has been duly  executed and delivered by the Borrower
         and  constitutes  the  legal,  valid  and  binding  obligation  of  the
         Borrower, enforceable in accordance with its terms.

                  (b) The execution, delivery and performance by the Borrower of
         this  Sixth  Amendment  has  been  duly  authorized  by  all  necessary
         corporate action and does not (i) require any authorization, consent or
         approval by any governmental  department,  commission,  board,  bureau,
         agency or  instrumentality,  domestic  or  foreign,  (ii)  violate  any
         provision  of any  law,  rule  or  regulation  or of any  order,  writ,
         injunction or decree presently in effect,  having  applicability to the
         Borrower,  or the Articles of Incorporation or By-Laws of the Borrower,
         or (iii)  result  in a breach  of or  constitute  a  default  under any
         indenture or loan or credit agreement or any other agreement,  lease or
         instrument  to  which  the  Borrower  is a party  or by which it or its
         properties may be bound or affected.

                  (c) All of the  representations  and  warranties  contained in
         Article V of the Credit Agreement,  as amended by this Sixth Amendment,
         are correct on and as of the date hereof and on the Effective  Date, as
         though  made on and as of such  date,  except to the  extent  that such
         representations and warranties relate solely to an earlier date.


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         5.       References.  Upon  the Effective  Date, all  references in the
Credit  Agreement  to "this  Agreement"  shall be deemed to refer to the  Credit
Agreement  as  amended  hereby;  and  any  and all  references  in the  Security
Documents  to the  Credit  Agreement  shall be  deemed  to  refer to the  Credit
Agreement as amended hereby.

         6. No Waiver.  The Borrower  acknowledges and agrees that the execution
of this Sixth Amendment and any documents  related hereto shall not be deemed to
be a waiver of any  Default or Event of Default  under the Credit  Agreement  or
breach,  default  or event of  default  under  any  Security  Document  or other
document  held by the Lender,  whether or not known to the Lender and whether or
not existing on the date of this Sixth Amendment.

         7. Release. The Borrower hereby absolutely and unconditionally releases
and  forever  discharges  the  Lender,  and  any and  all  participants,  parent
corporations,   subsidiary  corporations,   affiliated  corporations,  insurers,
indemnitors,  successors and assigns  thereof,  together with all of the present
and former  directors,  officers,  agents and employees of any of the foregoing,
from any and all  claims,  demands  or causes  of action of any kind,  nature or
description,  whether arising in law or equity or upon contract or tort or under
any state or federal law or  otherwise,  which the  Borrower has had, now has or
has made  claim to have  against  any such  person  for or by reason of any act,
omission,  matter,  cause or thing whatsoever arising from the beginning of time
to and including the date of this Sixth Amendment,  whether such claims, demands
and causes of action are matured or unmatured or known or unknown.

         8.  Expenses.  The Borrower  hereby  reaffirms its agreement  under the
Credit  Agreement  to pay or  reimburse  the  Lender on demand for all costs and
expenses  incurred by the Lender in connection  with the Credit  Agreement,  the
Security  Documents  and all other  documents  contemplated  thereby,  including
without  limitation  all  reasonable  fees and  disbursements  of legal counsel.
Without  limiting the  generality of the  foregoing,  the Borrower  specifically
agrees  to pay all fees and  disbursements  of  counsel  to the  Lender  for the
services  performed by such counsel in connection  with the  preparation of this
Sixth  Amendment  and the  documents  and  instruments  incidental  hereto.  The
Borrower  hereby agrees that the Lender may, at any time or from time to time in
its sole discretion and without further  authorization  by the Borrower,  make a
loan to the Borrower  under the Credit  Agreement,  or apply the proceeds of any
loan,  for the  purpose  of  paying  any such  fees,  disbursements,  costs  and
expenses.

         9.  Counterparts.   This  Sixth  Amendment,   the  Acknowledgement  and
Agreement  of  Corporate  Guarantors  and the  Acknowledgment  and  Agreement of
Validity Guarantors may be executed in any number of counterparts, each of which
when so executed  and  delivered  shall be deemed an  original  and all of which
counterparts, taken together, shall constitute one and the same instrument.



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                  IN WITNESS WHEREOF,  the parties hereto have caused this Sixth
Amendment to be duly executed as of the day and year first above written.

                    BORROWER:

                    FIELDS AIRCRAFT SPARES INCORPORATED (SEAL)


                    By:______________________________________
                    Its:_____________________________________


                    LENDER:
                    NORWEST BUSINESS CREDIT, INC. (SEAL)


                    By:_____________________________________
                    Its:____________________________________







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