SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d)
of the Securities Exchange Act of 1934

Date of Report (Date of earliest event reported):   September 10, 2007

TransDigm Group Incorporated

(Exact name of registrant as specified in its charter)

Delaware

(State or other jurisdiction of incorporation)

001-32833

(Commission File Number)

51-0484716

(I.R.S. Employer Identification No.)

1301 East 9th Street, Suite 3710, Cleveland, Ohio 44114
(216) 706-2939
(Address of principal executive offices and telephone number)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrants under any of the following provisions:

o  Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

o  Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

o  Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

o  Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Item 1.01               Entry into a Material Definitive Agreement

As previously disclosed, on August 10, 2007, Bruce Aerospace, Inc. (“Bruce Aerospace”), a Delaware corporation and a newly formed, wholly-owned subsidiary of TransDigm Inc. (“TransDigm”), a wholly-owned subsidiary of TransDigm Group Incorporated (“TD Group”), acquired certain assets from Bruce Industries, Inc., a Nevada corporation (“Bruce”), pursuant to the terms of that certain Asset Purchase Agreement, dated as of August 10, 2007, by and between Bruce and TransDigm (the “Asset Purchase”).

On September 10, 2007, in connection with the Asset Purchase and in accordance with the terms of that certain (i) Credit Agreement, dated as of June 23, 2006, among TransDigm, TD Group and the other parties named therein, as amended by that certain Amendment No. 1, Consent and Agreement, dated as of January 25, 2007 (as so amended, the “Credit Agreement”), and (ii) Guarantee and Collateral Agreement, dated as of June 23, 2006, among TransDigm, TD Group, Credit Suisse, as administrative agent and collateral agent, and the other parties named therein (as previously supplemented, the “Guarantee and Collateral Agreement”), Bruce Aerospace, Bruce Industries, Inc., a Colorado corporation and wholly-owned subsidiary of Bruce Aerospace (“Bruce Industries” and, together with Bruce Aerospace, the “New Subsidiaries”), and Credit Suisse entered into Supplement No. 4 to the Guarantee and Collateral Agreement (“Supplement No. 4”) and a Joinder Agreement to the Credit Agreement (the “Joinder Agreement”).

  Pursuant to the terms of Supplement No. 4, each of the New Subsidiaries agreed to, among other things, guarantee all of the indebtedness of TransDigm outstanding under the Credit Agreement from time to time.  In addition, under the terms of Supplement No. 4, each of the New Subsidiaries pledged substantially all of its assets to secure its guaranteed obligations under the Credit Agreement.  Pursuant to the terms of the Joinder Agreement, each of the New Subsidiaries has agreed that it will deemed to be a “Loan Party” and a “Loan Guarantor” for all purposes of the Credit Agreement.

The above summary of Supplement No. 4 and the Joinder Agreement is qualified in its entirety by reference to Supplement No. 4 and the Joinder Agreement, which are attached hereto as Exhibits 10.1 and 10.2, respectively, and incorporated herein by reference.

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Item 9.01               Financial Statements and Exhibits

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SIGNATURE

Pursuant to the requirements of the Securities Exchange Act of 1934, the Registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

Dated:  September 11, 2007

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EXHIBIT INDEX

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Exhibit 10.1

SUPPLEMENT NO. 4 dated as of September 10, 2007, to the Guarantee and Collateral Agreement dated as of June 23, 2006  (the “Guarantee and Collateral Agreement”), among TRANSDIGM INC., a Delaware corporation (the “Borrower”), TRANSDIGM GROUP INCORPORATED, a Delaware corporation (“Holdings”), each subsidiary of the Borrower listed on Schedule I thereto (each such subsidiary individually a “Subsidiary Guarantor” and collectively, the “Subsidiary Guarantors”; the Subsidiary Guarantors, Holdings and the Borrower are referred to collectively herein as the “Grantors”) and CREDIT SUISSE as administrative agent and collateral agent (in such capacity, the “Agent”) for the Secured Parties (as defined herein).

A.  Reference is made to the Credit Agreement dated as of June 23, 2006  (as amended, supplemented or otherwise modified from time to time, the “Credit Agreement”), among the Borrower, Holdings, each subsidiary of the Borrower from time to time party thereto, the lenders named therein (the “Lenders”), and Credit Suisse, as administrative agent and collateral agent (in such capacity, the “Agent”) for the Lenders.

B.  Capitalized terms used herein and not otherwise defined herein shall have the meanings assigned to such terms in the Credit Agreement or the Guarantee and Collateral Agreement referred to therein, as applicable.

C.  The Grantors have entered into the Guarantee and Collateral Agreement in order to induce the Lenders to make Loans and the Issuing Bank to issue Letters of Credit.  Section 7.16 of the Guarantee and Collateral Agreement provides that additional Domestic Subsidiaries of the Loan Parties may become Subsidiary Guarantors and Grantors under the Guarantee and Collateral Agreement by execution and delivery of an instrument in the form of this Supplement.  The undersigned Subsidiary (the “New Subsidiary”) is executing this Supplement in accordance with the requirements of the Credit Agreement to become a Subsidiary Guarantor and a Grantor under the Guarantee and Collateral Agreement in order to induce the Lenders to make additional Loans and the Issuing Bank to issue additional Letters of Credit and as consideration for Loans previously made and Letters of Credit previously issued.

Accordingly, the Agent and the New Subsidiary agree as follows:

SECTION 1.  In accordance with Section 7.16 of the Guarantee and Collateral Agreement, the New Subsidiary by its signature below becomes a Grantor and Subsidiary Guarantor under the Guarantee and Collateral Agreement with the same force and effect as if originally named therein as a Grantor and Subsidiary Guarantor and the New Subsidiary hereby (a) agrees to all the terms and provisions of the Guarantee and Collateral Agreement applicable to it as a Grantor and Subsidiary Guarantor thereunder and (b) represents and warrants that the representations and warranties made by it as a Grantor and Subsidiary Guarantor thereunder are true and correct in all material respects on and as of the date hereof.  In furtherance of the foregoing, the New Subsidiary, as security for the payment and performance in full of the Secured Obligations (as defined in the Guarantee and Collateral Agreement), does hereby create and grant to the Agent, its successors and assigns, for the benefit of the Secured Parties, their successors and assigns, a security interest in and lien on all of the New Subsidiary’s right, title and

interest in and to the Collateral (as defined in the Guarantee and Collateral Agreement) of the New Subsidiary.  Each reference to a “Grantor” or a “Subsidiary Guarantor” in the Guarantee and Collateral Agreement shall be deemed to include the New Subsidiary.  The Guarantee and Collateral Agreement is hereby incorporated herein by reference.

SECTION 2.  The New Subsidiary represents and warrants to the Agent and the other Secured Parties that this Supplement has been duly authorized, executed and delivered by it and constitutes its legal, valid and binding obligation, enforceable against it in accordance with its terms.

SECTION 3.  This Supplement may be executed in counterparts (and by different parties hereto on different counterparts), each of which shall constitute an original, but all of which when taken together shall constitute a single contract. This Supplement shall become effective when the Agent shall have received counterparts of this Supplement that, when taken together, bear the signatures of the New Subsidiary and the Agent.  Delivery of an executed signature page to this Supplement by facsimile transmission shall be as effective as delivery of a manually signed counterpart of this Supplement.

SECTION 4.  The New Subsidiary hereby represents and warrants that (a) set forth on Schedule I attached hereto is a true and correct schedule of the location of any and all Collateral of the New Subsidiary and (b) set forth under its signature hereto, is the true and correct legal name of the New Subsidiary, its jurisdiction of formation and the location of its chief executive office.

SECTION 5.  Except as expressly supplemented hereby, the Guarantee and Collateral Agreement shall remain in full force and effect.

SECTION 6.  THIS SUPPLEMENT SHALL BE GOVERNED BY, AND CONSTRUED IN ACCORDANCE WITH, THE LAWS OF THE STATE OF NEW YORK.

SECTION 7.  In case any one or more of the provisions contained in this Supplement should be held invalid, illegal or unenforceable in any respect, the validity, legality and enforceability of the remaining provisions contained herein and in the Guarantee and Collateral Agreement shall not in any way be affected or impaired thereby (it being understood that the invalidity of a particular provision in a particular jurisdiction shall not in and of itself affect the validity of such provision in any other jurisdiction). The parties hereto shall endeavor in good-faith negotiations to replace the invalid, illegal or unenforceable provisions with valid provisions the economic effect of which comes as close as possible to that of the invalid, illegal or unenforceable provisions.

SECTION 8.  All communications and notices hereunder shall be in writing and given as provided in Section 7.01 of the Guarantee and Collateral Agreement. All communications and notices hereunder to the New Subsidiary shall be given to it at the address set forth under its signature below.

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SECTION 9.  The New Subsidiary agrees to reimburse the Agent for its reasonable out-of-pocket expenses in connection with this Supplement, including the reasonable fees, other charges and disbursements of counsel for the Agent.

[Signature pages follow]

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IN WITNESS WHEREOF, the New Subsidiary and the Agent have duly executed this Supplement to the Guarantee and Collateral Agreement as of the day and year first above written.

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Exhibit 10.2

JOINDER AGREEMENT

THIS JOINDER AGREEMENT (this “Agreement”), dated as of September 10, 2007, is entered into between BRUCE AEROSPACE INC., a Delaware corporation and BRUCE INDUSTRIES, INC., a Colorado Corporation (each, a “New Subsidiary” and together, the “New Subsidiaries”), and CREDIT SUISSE, as Agent, under that certain Credit Agreement, dated as of June 23, 2006 (as the same may be amended, supplemented or otherwise modified from time to time, the “Credit Agreement”), among TransDigm Inc., a Delaware corporation (the “Borrower”), TransDigm Group Incorporated, a Delaware corporation, the Subsidiaries of the Borrower from time to time party thereto, the Lenders from time to time party thereto and the Agent.  All capitalized terms used herein and not otherwise defined shall have the meanings set forth in the Credit Agreement.

The New Subsidiaries and the Agent, for the benefit of the Lenders, hereby agree as follows:

1.             The New Subsidiaries hereby acknowledge, agree and confirm that, by their execution of this Agreement, the New Subsidiaries will be deemed to be Loan Parties under the Credit Agreement and Loan Guarantors for all purposes of the Credit Agreement and shall have all of the obligations of a Loan Party and a Loan Guarantor thereunder as if they had executed the Credit Agreement.  The New Subsidiaries hereby ratify, as of the date hereof, and agree to be bound by, all of the terms, provisions and conditions contained in the Credit Agreement, including without limitation (a) all of the representations and warranties of the Loan Parties set forth in Article III of the Credit Agreement (to the extent made or deemed made on or after the effective date hereof), (b) all of the covenants set forth in Articles V and Vl of the Credit Agreement and (c) all of the guaranty obligations set forth in the Guarantee and Collateral Agreement.  Without limiting the generality of the foregoing terms of this paragraph 1, the New Subsidiaries, subject to the limitations set forth in the Guarantee and Collateral Agreement, hereby absolutely and unconditionally guarantee, jointly and severally with the other Loan Guarantors, to the Agent and the Lenders, the prompt payment of the Secured Obligations in full when due (whether at stated maturity, upon acceleration or otherwise) to the extent of and in accordance with Guarantee and Collateral Agreement.

2.             If required, the New Subsidiaries are, simultaneously with the execution of this Agreement, executing and delivering such Collateral Documents (and such other documents and instruments) as requested by the Agent in accordance with the Credit Agreement.

3.             The New Subsidiaries hereby waive acceptance by the Agent and the Lenders of the guaranty by the New Subsidiaries upon the execution of this Agreement by the New Subsidiaries.

4.             This Agreement may be executed in any number of counterparts, each of which when so executed and delivered shall be an original, but all of which shall constitute one and the same instrument.

5.             THIS AGREEMENT AND THE RIGHTS AND OBLIGATIONS OF THE PARTIES HEREUNDER SHALL BE CONSTRUED IN ACCORDANCE WITH AND GOVERNED BY THE LAWS OF THE STATE OF NEW YORK.

IN WITNESS WHEREOF, the New Subsidiaries have caused this Agreement to be duly executed by their respective authorized officer, and the Agent, for the benefit of the Lenders, has caused the same to be accepted by its authorized officer, as of the day and year first above written.

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