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                              SUPPLEMENTAL INDENTURE              EXHIBIT 4.1.4


         SUPPLEMENTAL INDENTURE (this "SUPPLEMENTAL INDENTURE"), dated as of
October 6, 1999 among PCI Acquisition Co., Inc., a Kansas corporation d/b/a
PCI Newco, Inc. ("GUARANTOR"), a subsidiary of DeCrane Aircraft Holdings,
Inc. (or its permitted successor), a Delaware corporation (the "ISSUER"), the
other Guarantors (as defined in the Indenture referred to herein) and State
Street Bank and Trust Company, as trustee under the Indenture referred to
below (the "TRUSTEE").

                               W I T N E S S E T H

         WHEREAS, the Issuer has heretofore executed and delivered to the
Trustee an indenture (the "INDENTURE"), dated as of October 5, 1998 providing
for the issuance of an aggregate principal amount of up to $100.0 million of
12% Senior Subordinated Notes due 2008 (the "NOTES");

         WHEREAS, the Indenture provides that under certain circumstances
each Guarantor shall execute and deliver to the Trustee a supplemental
indenture, pursuant to which the Guarantor shall unconditionally guarantee
all of the Issuer's Obligations under the Notes and the Indenture on the
terms and conditions set forth herein (the "NOTE GUARANTEE"); and

         WHEREAS, pursuant to Section 9.06 of the Indenture, the Trustee is
authorized to execute and deliver this Supplemental Indenture.

         NOW THEREFORE, in consideration of the foregoing and for other good
and valuable consideration, the receipt of which is hereby acknowledged, each
Guarantor and the Trustee mutually covenant and agree for the equal and
ratable benefit of the Holders of the Notes as follows:

         1.       CAPITALIZED TERMS.  Capitalized terms used herein without
definition shall have the meanings assigned to them in the Indenture.

         2.       AGREEMENT TO GUARANTEE. The Guarantor hereby agrees as
follows:

         (a)      Along with all Guarantors named in the Indenture, to
jointly and severally Guarantee to each Holder of a Note authenticated and
delivered by the Trustee and to the Trustee and its successors and assigns,
irrespective of the validity and enforceability of the Indenture, the Notes
or the obligations of Issuer hereunder or thereunder, that:

                  (i) the principal of and interest on the Notes will be
         promptly paid in full when due, whether at maturity, by acceleration,
         redemption or otherwise, and interest on the overdue principal of and
         interest on the Notes, if any, is lawful, and all other obligations of
         the Issuer to the Holders or the Trustee hereunder or thereunder will
         be promptly paid in full or performed, all in accordance with the terms
         hereof and thereof; and

                  (ii) in case of any extension of time of payment or renewal of
         any Notes or any of such other obligations, that same will be promptly
         paid in full when due or performed in accordance with the terms of the
         extension or renewal, whether at stated maturity, by acceleration or
         otherwise. Failing payment when due of any amount so guaranteed or any
         performance so guaranteed for whatever reason, the Guarantors shall be
         jointly and severally obligated to pay the same immediately.

         (b) The obligations hereunder shall be unconditional, irrespective of
the validity, regularity or enforceability of the Notes or the Indenture, the
absence of any action to enforce the

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same, any waiver or consent by any Holder of the Notes with respect to any
provisions hereof or thereof, the recovery of any judgment against Issuer,
any action to enforce the same or any other circumstance which might
otherwise constitute a legal or equitable discharge or defense of a guarantor.

         (c)  The following is hereby waived: diligence, presentment, demand
of payment, filing of claims with a court in the event of insolvency or
bankruptcy of the Issuer, any right to require a proceeding first against the
Issuer, protest, notice and all demands whatsoever.

         (d)  This Note Guarantee shall not be discharged except by complete
performance of the obligations contained in the Notes and the Indenture.

         (e)  If any Holder or the Trustee is required by any court or
otherwise to return to the Issuer, the Guarantors, or any Custodian, trustee,
liquidator or other similar official acting in relation to either the Issuer
or the Guarantors, any amount paid by either to the Trustee or such Holder,
this Note Guarantee, to the extent theretofore discharged, shall be
reinstated in full force and effect.

         (f)  The Guarantor shall not be entitled to any right of subrogation
in relation to the Holders in respect of any obligations guaranteed hereby
until payment in full of all obligations guaranteed hereby.

         (g)  As between the Guarantors, on the one hand, and the Holders and
the Trustee, on the other hand, (x) the maturity of the obligations
guaranteed hereby may be accelerated as provided in Article 6 of the
Indenture for the purposes of this Note Guarantee, notwithstanding any stay,
injunction or other prohibition preventing such acceleration in respect of
the obligations guaranteed hereby, and (y) in the event of any declaration of
acceleration of such obligations as provided in Article 6 of the Indenture,
such obligations (whether or not due and payable) shall forthwith become due
and payable by the Guarantors for the purpose of this Note Guarantee.

         (h)  The Guarantors shall have the right to seek contribution from
any non-paying Guarantor so long as the exercise of such right does not
impair the rights of the Holders under the Guarantee.

         (i)  Pursuant to Section 11.03 of the Indenture, after giving effect
to any maximum amount and any other contingent and fixed liabilities that are
relevant under any applicable Bankruptcy or fraudulent conveyance laws, and
after giving effect to any collections from, rights to receive contribution
from or payments made by or on behalf of any other Guarantor in respect of
the obligations of such other Guarantor under Article 11 of the Indenture
shall result in the obligations of such Guarantor under its Note Guarantee
not constituting a fraudulent transfer or conveyance.

         3.   EXECUTION AND DELIVERY. Each Guarantor agrees that the Note
Guarantees shall remain in full force and effect notwithstanding any failure
to endorse on each Note a notation of such Note Guarantee.

         4.   GUARANTOR MAY CONSOLIDATE ETC. ON CERTAIN TERMS.

         (a)  No Guarantor may consolidate with or merge with or into
(whether or not such Guarantor is the surviving Person), another corporation,
Person or entity whether or not affiliated with such Guarantor unless:

              (i)  subject to Section 5(a) hereof, the Person formed by or
         surviving any such consolidation or merger (if other than such
         Guarantor) assumes all the obligations of such Guarantor pursuant to a
         supplemental indenture in form and substance reasonably satisfactory to
         the Trustee, under the Notes, the Indenture and the Registration Rights
         Agreement;

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              (ii)  immediately after giving effect to such transaction, no
         Default or Event of Default exists; and

              (iii) Issuer would, at the time of such transaction and after
         giving pro forma effect thereto and if such transaction had occurred at
         the beginning of the applicable four-quarter period, be permitted to
         incur at least $1.00 of additional Indebtedness pursuant to the Fixed
         Charger Coverage Ratio test set forth in Section 4.09 of the Indenture
         by virtue of Issuer's pro forma Cash Flow Coverage Ratio, immediately
         after giving effect to such transaction, to incur at least $1.00 of
         additional Indebtedness pursuant to the Cash Flow Coverage Ratio test
         set forth in Section 4.07 of the Indenture;

PROVIDED THAT, the requirements of clause (iii) of this Section 4(a) will not
apply in the case of a consolidation with or merger with or into the Issuer
or another Guarantor.

         (b) In case of any such consolidation, merger, sale or conveyance
and upon the assumption by the successor Person, by supplemental indenture
executed and delivered to the Trustee in the form of Exhibit E to the
Indenture or otherwise satisfactory in form to the Trustee, of the Note
Guarantee and the due and punctual performance of all of the covenants and
conditions of the Indenture to be performed by the Guarantor, such successor
Person shall succeed to and be substituted for the Guarantor with the same
effect as if it had been named herein as a Guarantor. All the Note Guarantees
so issued shall in all respects have the same legal rank and benefit under
the Indenture as the Note Guarantees theretofore and thereafter issued in
accordance with the terms of the Indenture as though all of such Note
Guarantees had been issued at the date of the execution hereof.

         (c) Except as set forth in Articles 4 and 5 of the Indenture, and
notwithstanding clauses (a) and (b) above, nothing contained in the Indenture
or in any of the Notes shall prevent any consolidation or merger of a
Guarantor with or into the Issuer or another Guarantor, or shall prevent any
sale or conveyance of the property of a Guarantor as an entirety or
substantially as an entirety to the Issuer or another Guarantor.

         5.  RELEASES.

         (a) In the event of a sale or other disposition of all of the assets
of any Guarantor, by way of merger, consolidation or otherwise, or a sale or
other disposition of all of the capital stock of any Guarantor, such
Guarantor (in the event of a sale or other disposition, by way of such a
merger, consolidation or otherwise, of all of the capital stock of such
Guarantor) or the corporation acquiring the property (in the event of a sale
or other disposition of all of the assets of such Guarantor) will be released
and relieved of any obligations under its Note Guarantee; PROVIDED that the
Net Proceeds of such sale or other disposition are applied in accordance with
the applicable provisions of the Indenture, including without limitation
Section 4.10 of the Indenture. Upon delivery by the Issuer to the Trustee of
an Officers' Certificate and an Opinion of Counsel to the effect that such
sale or other disposition was made by the Issuer in accordance with the
applicable provisions of the Indenture, including, without limitation,
Section 4.10 of the Indenture, the Trustee shall execute any documents
reasonably required in order to evidence the release of any Guarantor from
its obligations under its Note Guarantee.

         (b) Any Guarantor not released from its obligations under its Note
Guarantee shall remain liable for the full amount of principal of and
interest on the Notes and for the other obligations of any Guarantor under
the Indenture as provided in Article 11 of the Indenture.

         6.  NO RECOURSE AGAINST OTHERS. No past, present or future director,
officer, employee, incorporator, stockholder or agent of the Guarantor, as
such, shall have any liability for any obligations of the Issuer or any
Guarantor under the Notes, any Note Guarantees, the Indenture or this
Supplemental Indenture or for any claim based on, in respect of, or by reason
of, such obligations or their creation. Each Holder of the Notes by accepting
a Note waives and

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releases all such liability. The waiver and release are part of the
consideration for issuance of the Notes. Such waiver may not be effective to
waive liabilities under the federal securities laws and it is the view of the
Commission that such a waiver is against public policy.

         7.  NEW YORK LAW TO GOVERN. THE INTERNAL LAW OF THE STATE OF NEW
YORK SHALL GOVERN AND BE USED TO CONSTRUE THIS SUPPLEMENTAL INDENTURE BUT
WITHOUT GIVING EFFECT TO APPLICABLE PRINCIPLES OF CONFLICTS OF LAW TO THE
EXTENT THAT THE APPLICATION OF THE LAWS OF ANOTHER JURISDICTION WOULD BE
REQUIRED THEREBY.

         8.  COUNTERPARTS. The parties may sign any number of copies of this
Supplemental Indenture. Each signed copy shall be an original, but all of
them together represent the same agreement.

         9.  EFFECT OF HEADINGS. The Section headings herein are for
convenience only and shall not affect the construction hereof.

         10.  THE TRUSTEE. The Trustee shall not be responsible in any manner
whatsoever for or in respect of the validity or sufficiency of this
Supplemental Indenture or for or in respect of the recitals contained herein,
all of which recitals are made solely by each Guarantor and the Issuer.

                                               SIGNATURES

         Dated as of October 6, 1999           DECRANE AIRCRAFT HOLDINGS, INC.


                                               BY:      _______________________

                                                        Name:

                                                        Title:





                                               AEROSPACE DISPLAY SYSTEMS, INC.





                                               BY:      _______________________

                                                        Name:

                                                        Title:




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                                               AUDIO INTERNATIONAL, INC.





                                               BY:      _______________________

                                                        Name:

                                                        Title:





                                               AVTECH CORPORATION





                                               BY:      _______________________

                                                        Name:

                                                        Title:





                                               CORY COMPONENTS, INC.





                                               BY:      _______________________

                                                        Name:

                                                        Title:





                                               DETTMERS INDUSTRIES, INC.





                                               BY:      _______________________

                                                        Name:

                                                        Title:


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                                             ELSINORE AEROSPACE
                                             SERVICES, INC.





                                             BY:      _________________________

                                                      Name:

                                                      Title:





                                             ELSINORE ENGINEERING, INC.





                                             BY:      _________________________

                                                      Name:

                                                      Title:





                                             HOLLINGSEAD INTERNATIONAL,
                                             INC.



                                             BY:      _________________________

                                                      Name:

                                                      Title:





                                             TRI-STAR ELECTRONICS
                                             INTERNATIONAL, INC.





                                             BY:      _________________________

                                                      Name:

                                                      Title:


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                                      PATS, INC.





                                      BY:      _________________________

                                               Name:

                                               Title:





                                      PATRICK AIRCRAFT TANK SYSTEMS, INC.

                                      BY:      _________________________

                                               Name:

                                               Title:



                                      PATS SUPPORT, INC.





                                      BY:      _________________________

                                               Name:

                                               Title:





                                      PATS AIRCRAFT AND ENGINEERING CORPORATION

                                      BY:      _________________________

                                               Name:

                                               Title:





                                       FLIGHT REFUELING, INC.





                                       BY:      _________________________

                                                Name:

                                                Title:


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                                             CUSTOM WOODWORK &
                                             PLASTICS, INC.





                                             BY:      _________________________

                                                      Name:

                                                      Title:





                                             PCI ACQUISITION CO., INC., d/b/a
                                             PCI Newco, Inc.





                                             BY:      _________________________

                                                      Name:

                                                      Title:







                                             STATE STREET BANK AND TRUST COMPANY





                                             BY:      _________________________

                                                      Name:

                                                      Title:


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