Exhibit 4.5(c)


                                    THIRD SUPPLEMENTAL INDENTURE dated as of
                           September 15, 1998 (this "Supplemental Indenture"),
                           to the Indenture dated as of February 29, 1996 (the
                           "Indenture"), between HEXCEL CORPORATION, a Delaware
                           corporation (the "Company"), and U.S. BANK TRUST
                           NATIONAL ASSOCIATION (formerly known as First Trust
                           of California, National Association), a national
                           banking association, as trustee (the "Trustee"), as
                           previously supplemented. Capitalized terms used but
                           not defined in this Supplemental Indenture shall have
                           the meanings ascribed to them in the Indenture.

                  WHEREAS, the Company desires to amend and waive certain
provisions of the Indenture, among other things, in respect of (i) the Company's
new Credit Agreement (as defined in Section 1(b) below) and (ii) the
Clark-Schwebel Acquisition (as defined in Section 1(a) below);

                  WHEREAS, Section 9.02 of the Indenture authorizes the Company
and the Trustee to amend and waive certain provisions of the Indenture with the
consent of the Securityholders;

                  WHEREAS, Ciba Specialty Chemicals Inc., a corporation
organized under the laws of Switzerland ("Ciba"), is the Holder of all of the
Securities; and

                  WHEREAS, Ciba and the Company have agreed to modify and waive
the terms of the Securities as set forth in this Supplemental Indenture, and
accordingly, Ciba consents to this Supplemental Indenture.

                  NOW, THEREFORE, the Company and the Trustee hereby agree for
the equal and ratable benefit of the Securityholders as follows:

                  SECTION 1. AMENDMENT OF INDENTURE. (a) Section 1.01 of the
Indenture is hereby amended by adding thereto the following definitions in their
proper alphabetical order:

                           "'ASAHI-SCHWEBEL' means Asahi-Schwebel Co., Ltd., a
                  joint venture in which the Company or a Subsidiary of the
                  Company will own an interest after giving effect to the
                  Clark-Schwebel Acquisition."







                           "'ASAHI-SCHWEBEL (TAIWAN)' means Asahi-Schwebel
                  (Taiwan) Co, Ltd., a joint venture between Asahi-Schwebel and
                  AlliedSignal."

                           "'ASAHI-SCHWEBEL INTERGLAS (PHILIPPINES)' means
                  Asahi-Schwebel Interglas Corporation (Philippines), a proposed
                  joint venture between Asahi-Schwebel and Interglas."

                           "'ASIAN COMPOSITE MANUFACTURING' means Asian
                  Composite Manufacturing Sdn. Bhd., a proposed joint venture
                  among the Company, The Boeing Company, Sime Darby Berhad and
                  Malaysia Helicopter Services."

                           "'BHA AERO COMPOSITE PARTS' means BHA Aero Composite
                  Parts Co., Ltd., a proposed joint venture among the Company,
                  The Boeing Company and Aviation Industries of China."

                           "'CLARK-SCHWEBEL ACQUISITION' means the acquisition
                  and lease of certain assets of Clark-Schwebel Holdings, Inc.
                  and its subsidiaries by the Company or a Subsidiary of the
                  Company pursuant to (i) that certain Asset Purchase Agreement,
                  dated as of July 25, 1998, by and among Stamford CS
                  Acquisition Corp., Clark-Schwebel Holdings, Inc.,
                  Clark-Schwebel, Inc. and the Company, and (ii) that certain
                  Lease Agreement, attached as Exhibit H to such Asset Purchase
                  Agreement, to be entered into by and between CSI Trust, as
                  landlord, and the Company or a Subsidiary of the Company, as
                  tenant, as each of the same may be amended, supplemented or
                  otherwise modified from time to time."

                           "'CLARK-SCHWEBEL JOINT VENTURES' means (i)
                  Asahi-Schwebel, (ii) Asahi-Schwebel (Taiwan), (iii)
                  Asahi-Schwebel Interglas (Philippines), (iv) Clark-Schwebel
                  Tech-Fab and (v) Interglas."

                           "'CLARK-SCHWEBEL TECH-FAB' means Clark-Schwebel
                  Tech-Fab Company, a New York partnership and a joint venture
                  in which the Company or a Subsidiary of the Company will own
                  an interest after giving effect to the Clark-Schwebel
                  Acquisition."

                           "'COMPANY STOCK REPURCHASE PROGRAM' means the
                  purchase from time to time by the Company of its Capital Stock
                  not to exceed $50,000,000 in the aggregate from and after
                  August 5, 1998."

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                           "'INTERGLAS' means CS Interglas AG, a German stock
                  corporation."

                           "'POLELINE ASSET MANAGEMENT' means Poleline Asset
                  Management, LLC, a California limited liability company and a
                  joint venture in which Hexcel Beta Corp. owns a 50% interest."

                  (b) The definition of "Credit Agreement" contained in Section
1.01 of the Indenture is hereby amended to read as follows:

                           "'CREDIT AGREEMENT' means, collectively, the Credit
                  Agreement dated as of September 15, 1998, among the Company,
                  certain of its Subsidiaries, the institutions from time to
                  time party thereto as Lenders, Citibank, N.A. (or any
                  successor thereto), in its separate capacity as collateral
                  agent for the Lenders and Credit Suisse First Boston (or any
                  successor thereto), in its separate capacity as administrative
                  agent and documentation agent for the Lenders, including any
                  related notes, letters of credit, guarantees, collateral
                  documents, instruments and agreements executed in connection
                  therewith, and in each case as the same may from time to time
                  be amended, renewed, replaced, refunded, supplemented, or
                  otherwise modified at the option of the parties thereto
                  (including, without limitation, any extension of maturity
                  thereof or increase in commitments or principal amounts
                  eligible to be borrowed thereunder), and any other agreement
                  pursuant to which any of the Indebtedness, commitments,
                  obligations, costs, expenses, fees, reimbursements and other
                  indemnities payable or owing thereunder may be replaced or
                  refinanced."

                  (c) The definition of "Existing Joint Ventures" contained in
Section 1.01 of the Indenture is hereby amended to read as follows:

                           "'EXISTING JOINT VENTURES' means (i) Knytex, (ii)
                  DIC, (iii) Fyfe and (iv) the Clark-Schwebel Joint Ventures."

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                  (d) The definition of "Permitted Investment" contained in
Section 1.01 of the Indenture is hereby amended by deleting the word "and" after
the end of clause (vi) thereof and adding new clauses (viii) and (ix) thereto to
read as follows:

                  "; (viii) the assets of Clark-Schwebel Holdings, Inc. and its
                  subsidiaries in connection with the Clark-Schwebel
                  Acquisition; and (ix) Interglas."

                  (e) Sections 4.03(b)(vi) and 4.03(b)(x) of the Indenture are
hereby amended by deleting each reference to "Section 13.1(j)" therein and
replacing it with "Section 14.2(g)".

                  (f) Section 4.03(b)(viii) of the Indenture is hereby amended
by deleting the reference to "$12,500,000" therein and substituting
"$100,000,000" therefor.

                  (g) Section 4.03(b)(xiii) of the Indenture is hereby amended
to read as follows:

                           "(xiii) Guarantees relating to the Acquisition or the
                  Clark-Schwebel Acquisition;"

                  (h) Section 4.03(b) of the Indenture is hereby amended by (A)
deleting the word "or" at the end of clause (xv) thereof, (B) deleting the "."
at the end of clause (xvi) thereof and replacing it with the phrase "; or" and
(C) adding a new clause (xvii) thereto to read as follows:

                           "(xvii) Indebtedness of a Clark-Schwebel Joint
                  Venture outstanding on the date such Clark-Schwebel Joint
                  Venture becomes a Subsidiary."

                  (i) Section 4.04(b) of the Indenture is hereby amended by (A)
deleting the word "or" at the end of clause (ix) thereof, (B) deleting the "."
at the end of clause (x) thereof and replacing it with a ";" and (C) adding new
clauses (xi) and (xii) thereto to read as follows:

                           "(xi) the purchase from time to time by the Company
                  of its Capital Stock (A) with the proceeds of the exercise by
                  grantees under any equity-based incentive plan or (B) pursuant
                  to the Company Stock Repurchase Program; or

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                           (xii) the purchase, redemption, retirement or other
                  acquisition of the Capital Stock of Interglas."

                  (j) Clause (A) of Section 4.07(a) of the Indenture is hereby
amended to read as follows:

                  "(A) any transaction between the Company or any of its
                  Subsidiaries and (i) any Permitted Holder, (ii) Hexcel
                  Foundation so long as such foundation remains a not-for-profit
                  institution for the purposes of California law, (iii) Fyfe,
                  (iv) Hexcel-DIC Partnership, (v) Knytex, (vi) Poleline Asset
                  Management, (vii) BHA Aero Composite Parts, (viii) Asian
                  Composite Manufacturing, (ix) any Clark-Schwebel Joint Venture
                  and (x) any director or officer of Interglas in connection
                  with the acquisition of Interglas Capital Stock;"

                  SECTION 2. WAIVER. Any Default or Event of Default arising
under the Indenture in connection with the consummation of the Clark-Schwebel
Acquisition and the transactions contemplated thereby are hereby waived.

                  SECTION 3. CONFIRMATION. Except as hereby expressly amended or
waived, the Indenture is in all respects ratified and confirmed and all the
terms, conditions and provisions thereof shall remain in full force and effect.

                  SECTION 4. EFFECTIVENESS. This Supplemental Indenture shall
take effect immediately up on its execution and delivery by the Company, the
Trustee and Ciba.

                  SECTION 5. COUNTERPARTS. This Supplemental Indenture may be
executed in any number of counterparts, each of which, when so executed, shall
be deemed to be an original, but all of which shall together constitute but one
contract.

                  SECTION 6. EXECUTION. Delivery of an executed counterpart of a
signature page by facsimile transmission shall be effective as delivery of a
manually executed counterpart of this Supplemental Indenture.

                  SECTION 7. APPLICABLE LAW. THIS SUPPLEMENTAL INDENTURE SHALL
BE GOVERNED BY, AND CONSTRUED IN ACCORDANCE WITH, THE LAWS OF THE STATE OF NEW
YORK.

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                  IN WITNESS WHEREOF, the parties hereto have caused this
Supplemental Indenture to be duly executed by their duly authorized officers,
all as of the date and year first above.

                                                     HEXCEL CORPORATION


                                                     by
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                                                        Name:
                                                        Title:


                                                     U.S. BANK TRUST NATIONAL
                                                     ASSOCIATION


                                                     by
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                                                         Name:
                                                         Title:


CONSENTED AND AGREED TO BY:

CIBA SPECIALTY CHEMICALS INC.


         by
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             Name:
             Title:


         by
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             Name:
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                              OFFICERS' CERTIFICATE


                  The undersigned hereby certify that they are duly elected
officers of Hexcel Corporation (the "Company"), and in such capacities they
state the following with respect to the Third Supplemental Indenture, dated as
of September ____, 1998 (the "Supplemental Indenture"), between the Company and
U.S. Bank Trust National Association (formerly known as First Trust of
California, National Association), as trustee (the "Trustee"), which supplements
the Indenture, dated as of February 29, 1996 as previously supplemented (the
"Indenture"), between the Company and the Trustee with respect to the Increasing
Rate Senior Subordinated Notes due 2003 (the "Notes") of the Company. Ciba
Specialty Chemicals Inc. has consented to the Supplemental Indenture.

                  Based upon the foregoing and the investigation referred to
below, the undersigned certify that:

                  1. The undersigned have read the Supplemental Indenture and
Section 9.02 of the Indenture.

                  2. The foregoing investigation was, in the opinion of the
undersigned, sufficient to enable to undersigned the express the opinion whether
the provisions of Section 9.02 of the Indenture have been complied with; and

                  3. The undersigned are of the opinion that the Supplemental
Indenture is permitted by Section 9.02 of the indenture and that all conditions
precedent under the Indenture to the execution of the Supplemental Indenture
have been complied with.

                  IN WITNESS WHEREOF, the undersigned have executed this
Officer's Certificate as of the ____ day of September, 1998.


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