First Supplemental Indenture

                          Dated as of February 20, 1998

                                       to

                                    INDENTURE

                         Dated as of September 30, 1997

                                     between

                          FIELDS AIRCRAFT SPARES, INC.

                                       and

                      ETABLISSEMENT POUR LE PLACEMENT PRIVE

                8.5% Subordinated Redeemable Debentures Due 2000


         WHEREAS,  Fields Aircraft  Spares,  Inc. (the "Company") has heretofore
executed and delivered to Etablissement Pour le Placement Prive (the "Trustee"),
an indenture (the "Indenture") dated as of September 30, 1997, providing for the
issuance  of  $10,000,000  principal  amount  of  8.5%  Subordinated  Redeemable
Debentures Due 2000 (the "Debentures"); and

         WHEREAS, on November 14, 1997, pursuant to Section 14.1(b), the Company
redeemed $2,000,000 principal amount of Debentures; and

         WHEREAS,  Section 10.2 of the Indenture  provides,  among other things,
that the  Company  and the  Trustee  may,  with the consent of not less than the
holders of a majority in aggregate  principal  amount of  Debentures at the time
outstanding, amend the Indenture; and

         WHEREAS,  the Company, by resolutions adopted by its Board of Directors
on February 13, 1998, has been authorized to enter into this First  Supplemental
Indenture  upon  obtaining  the  approval of the  Trustees and a majority of the
holders of Debentures; and

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         WHEREAS,  all other conditions precedent to the execution of this First
Supplemental Indenture have been complied with;

         NOW THEREFORE, the Company and the Trustee are executing and delivering
this First Supplemental Indenture.

         Section 1.    Amendment of Indenture.  Section 14.1(a) of the Indenture
is amended by adding the following sentence after the first sentence:

         Notwithstanding  the  foregoing,  from  February 20, 1998,  to June 30,
         1998,  the holder  shall have a one-time  right to convert  20% of such
         holder's  original  principal  amount of Debentures,  or any portion of
         such principal amount that is $1,000 or an integral  multiple  thereof,
         in the manner described in this Section 14.1(a),  at a Conversion Price
         of $9.75 per share;  from February 20, 1998, to September 30, 1998, the
         holder shall have an additional one-time right to convert an additional
         20% of such holder's  original  principal amount of Debentures,  or any
         portion of such principal amount that is $1,000 or an integral multiple
         thereof,  in  the  manner  described  in  this  Section  14.1(a),  at a
         Conversion  Price of $11.00 per share;  and from  February 20, 1998, to
         December 31, 1998,  the holder shall have an additional  one-time right
         to convert an additional 20% of such holder's original principal amount
         of Debentures,  or any portion of such principal  amount that is $1,000
         or an  integral  multiple  thereof,  in the  manner  described  in this
         Section  14.1(a)  (collectively,  the  "Additional  Conversions").  The
         Additional Conversions shall be in addition to the Mandatory Conversion
         described in Section 14.1(b) and the conversion  described in the first
         sentence of Section 14.1(a).

         Section  2.  Ratification  of  Indenture.  As  amended  by  this  First
Supplemental  Indenture,  the  Indenture  and  Debentures  are in  all  respects
ratified and confirmed  and the Indenture so amended by this First  Supplemental
Indenture shall be read, taken and construed as one and the same instrument.

         Section 6.   Counterparts.  This First  Supplemental Indenture  may  be
executed  in any  number of  counterparts,  each of which so  executed  shall be
deemed to be an original, but all of such counterparts shall together constitute
but one and the same instrument.
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         IN  WITNESS  WHEREOF,   the  parties  hereto  have  caused  this  First
Supplemental  Indenture  to be  signed  and  acknowledged  by  their  respective
officers  thereunto duly authorized and their  respective  corporate seals to be
hereunto duly affixed and attested, all as of February 20, 1998.

                                        FIELDS AIRCRAFT SPARES, INC.

                                        By: /s/ Peter Frohlich
                                            ----------------------
                                        Name:  Peter Frohlich
                                        Title: Chairman
ATTEST

/s/ Judith White
- -------------------
Name: Judith White

                                        ETABLISSEMENT POUR LE PLACEMENT
                                        PRIVE, as Trustee

                                        By: /s/ Herbert R. Towning
                                           --------------------------
                                        Name:  Herbert R. Towning
                                        Title: Director
ATTEST

/s/ Judith White
- ---------------------
Name: Judith White

                                        VON GRAFFENREID AG, as Paying Agent

                                        By:  /s/ Dr. R. Wicki ppa. M. Eggimann
                                           -----------------------------------
                                      Name:  Dr. R. Wicki ppa. M. Eggimann
                                     Title:  Managing Director/Vice President
ATTEST

/s/ M. Parolini
- ------------------------
Name: M. Parolini

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