UNITED STATES

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): June 25, 2013

TransDigm Group Incorporated

(Exact name of registrant as specified in its charter)

Registrant’s telephone number, including area code: (216) 706-2960

Not Applicable

(Former name or former address, if changed since last report)

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

On June 25, 2013, TransDigm Group Incorporated (“TransDigm Group”) issued a press release relating to the proposed offering of $500 million in aggregate principal amount of senior subordinated notes due 2021 (the “Notes”) by TransDigm Inc., its wholly-owned subsidiary, pursuant to a confidential offering memorandum in a private placement under Rule 144A and Regulation S of the Securities Act of 1933 (the “Securities Act”). A copy of the press release is furnished as Exhibit 99.1 to this Current Report on Form 8-K.

The Notes will not be registered under the Securities Act or any state securities laws and may not be offered or sold in the United States without registration or an applicable exemption from the registration requirements of the Securities Act and applicable state securities laws. Neither the press release nor this Current Report on Form 8-K constitutes an offer to sell or the solicitation of an offer to buy the Notes, nor shall there be any sale of the Notes in any state in which such offer, solicitation or sale would be unlawful prior to registration or qualification under the securities laws of any such state.

TransDigm Inc. intends to use all or a portion of the net proceeds from the offering of the Notes, together with the net proceeds of the borrowing of $700.0 million of additional incremental term loans and cash on hand, to fund a dividend in the range of $1 billion to $1.8 billion to the holders of the common stock of TransDigm Group, to pay related transaction expenses and for general corporate purposes.

The information in this Item 7.01 on Form 8-K and in Exhibit 99.1 is being furnished and shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, nor shall it be deemed incorporated by reference in filings under the Securities Act.

The following exhibit is being furnished with this Current Report on Form 8-K:

99.1     Press Release

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: June 25, 2013

EXHIBIT INDEX

99.1     Press Release.

Exhibit 99.1

TransDigm Group Announces Proposed Private Offering of $500 Million Senior Subordinated Notes due 2021

Cleveland, Ohio, June 25, 2013/PRNewswire / — TransDigm Group Incorporated (“TransDigm Group”) (NYSE: TDG) announced today that its wholly-owned subsidiary, TransDigm Inc. (the “Company”), is planning, subject to market and other conditions, to offer $500 million aggregate principal amount of senior subordinated notes due 2021 (the “Notes”) in a private offering that is exempt from the registration requirements of the Securities Act of 1933 (the “Securities Act”). TransDigm Group has received from its lenders the requisite consents to a previously announced proposed amendment to its senior secured credit facilities, which was a condition to the offering of the Notes. It is expected that the Notes will be guaranteed, with certain exceptions, by TransDigm Group and certain of the Company’s existing and future domestic subsidiaries on a senior subordinated basis.

The Company intends to use all or a portion of the net proceeds from the offering of the Notes, together with the net proceeds of the borrowing of $700 million of additional incremental term loans and cash on hand, to fund a dividend in the range of $1 billion to $1.8 billion to the holders of the common stock of TransDigm Group, to pay related transaction expenses and for general corporate purposes.

This is not an offer to sell or the solicitation of an offer to buy any securities. The Notes and related guarantees are being offered only to qualified institutional buyers in reliance on the exemption from registration set forth in Rule 144A under the Securities Act, and outside the United States to non-U.S. persons in reliance on the exemption from registration set forth in Regulation S under the Securities Act. The Notes and the related guarantees have not been registered under the Securities Act, or the securities laws of any state or other jurisdiction, and may not be offered or sold in the United States without registration or an applicable exemption from the Securities Act and applicable state securities or blue sky laws and foreign securities laws.

About TransDigm Group

TransDigm Group, through its wholly-owned subsidiaries, is a leading global designer, producer and supplier of highly engineered aircraft components for use on nearly all commercial and military aircraft in service today. Major product offerings, substantially all of which are ultimately provided to end-users in the aerospace industry, include mechanical/electro-mechanical actuators and controls, ignition systems and engine technology, specialized pumps and valves, power conditioning devices, specialized AC/DC electric motors and generators, NiCad batteries and chargers, engineered latching and locking devices, rods and locking devices, engineered connectors and elastomers, cockpit security components and systems, specialized cockpit displays, aircraft audio systems, specialized lavatory components, seatbelts and safety restraints, engineered interior surfaces and lighting and control technology.

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Safe Harbor Statement

This press release contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995.

All forward-looking statements involve risks and uncertainties which could affect TransDigm Group’s actual results and could cause its actual results to differ materially from those expressed or implied in any forward-looking statements made by, or on behalf of, TransDigm Group. These risks and uncertainties include but are not limited to: the sensitivity of our business to the number of flight hours that our customers’ planes spend aloft and our customers’ profitability, both of which are affected by general economic conditions; future terrorist attacks; our reliance on certain customers; the U.S. defense budget and risks associated with being a government supplier; failure to maintain government or industry approvals; failure to complete or successfully integrate acquisitions; our substantial indebtedness; potential environmental liabilities; and other factors. Further information regarding the important factors that could cause actual results to differ materially from projected results can be found in TransDigm Group’s Annual Report on Form 10-K and other reports that TransDigm Group or its subsidiaries have filed with the Securities and Exchange Commission. Except as required by law, TransDigm Group undertakes no obligation to revise or update the forward-looking statements contained in this press release.

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