THE CORPORATE LIBRARY

Related Party Transactions and Outside Related Director Information

TransDigm Group Incorporated (TDG)

3/15/2006 424B4 Information

Tax Sharing Agreement

TD Group, TransDigm Holdings, TransDigm Inc. and each domestic subsidiary of TransDigm Inc. are parties to a tax sharing agreement. Under the terms of the tax sharing agreement, TransDigm Holdings, TransDigm Inc. and each of TransDigm Inc.'s domestic subsidiaries are obligated to make payments to TD Group equal to the amount of federal and state income taxes that they would have owed if they did not file federal and state income tax returns on a consolidated or combined basis (as limited by their pro rata share of the actual consolidated or combined tax liability of the group).

Stockholders' Agreement and Management Stockholders' Agreement

In connection with the closing of the Mergers, TD Group, Warburg Pincus, certain of our employees and certain other investors named therein, entered into a stockholders' agreement. Effective upon the closing of this offering, substantially all of the operative provisions of the stockholders' agreement will terminate. However, under the terms of the stockholders' agreement, our obligation to nominate and use our best efforts to have elected to our Board of Directors certain individuals designated by Warburg Pincus will remain in effect following the closing of this offering. Specifically, so long as Warburg Pincus and its affiliates beneficially own at least 25% of our outstanding shares of common stock, we are required to nominate and use our best efforts to have elected to our Board of Directors that number of individuals that are designated by Warburg Pincus that is equal to the greater of (i) three and (ii) a number of directors (rounded up to the nearest whole number) equal to the number of members of our Board of Directors multiplied by the Warburg Percentage as of the date of nomination of directors to our Board of Directors. In addition, under the terms of our stockholders' agreement, for so long as Warburg Pincus and its affiliates beneficially own at least ten percent but less than 25% of our outstanding shares of common stock, we are required to nominate and use our best efforts to have elected to our Board of Directors that number of individuals that are designated by Warburg Pincus that is equal to the greater of (i) two and (ii) a number of directors (rounded up to the nearest whole number) equal to the number of members of our Board of Directors multiplied by the Warburg Percentage as of the date of nomination of directors to our Board of Directors. Finally, under the terms of our stockholders' agreement, for so long as Warburg Pincus and its affiliates beneficially own at least five percent but less than ten percent of our outstanding shares of common stock, we are required to nominate and use our best efforts to have elected to our Board of Directors that number of individuals that are designated by Warburg Pincus that is equal to the greater of (i) one and (ii) a number of directors (rounded up to the nearest whole number) equal to the number of members of our Board of Directors multiplied by the Warburg Percentage as of the date of nomination of directors to our Board of Directors.

In connection with the closing of the Mergers, TD Group, Warburg Pincus and certain of our employees entered into a management stockholders' agreement governing the shares of our common stock or options to purchase shares of our common stock that certain of our employees held or had the right to acquire. Upon the closing of this offering, the management stockholders' agreement will terminate in accordance with its terms and will cease to be of any further force or effect.

TD Group, LLC—Limited Liability Company Agreement

Upon the completion of this offering, Warburg Pincus, A.S.F. Co-Investment Partners II, L.P., AlpInvest Partners CS Investments 2003 C.V., AlpInvest Partners Later Stage Co-Investments Custodian II C.V., ML TD Holdings, LLC, Teachers Insurance and Annuity Association of America and Michael Graff, one of our directors, intend to contribute to TD Group, LLC all of the shares of our common stock owned by them (after giving effect to the completion of this offering), in exchange for membership interests in TD Group, LLC. Upon the completion of this offering, (i) TD Group, LLC will own an aggregate of 31,914,651 shares of our common stock (or 31,093,057 if the underwriters' over-allotment option is exercised in full) and (ii) Warburg Pincus will own approximately 84.8% of the membership interests of TD Group, LLC (or approximately 84.4% if the underwriters' over-allotment option is exercised in full). Warburg Pincus will also be the managing member of TD Group, LLC and, as such, will have voting and investment power over all shares of common stock of TD Group that will be held by TD Group, LLC upon the completion of this offering, including shares of common stock with respect to which Warburg Pincus does not have a pecuniary interest.

Employment Agreement with W. Nicholas Howley, Chief Executive Officer and Chairman of the Board of Directors

Pursuant to the terms of Mr. Howley's employment agreement, we have agreed to propose Mr. Howley for re-election to the Board of Directors. Under the terms of Mr. Howley's employment agreement, Warburg Pincus has agreed to vote all of the shares it controls in favor of Mr. Howley's re-election.

Registration Rights Agreement

We are a party to a registration rights agreement with TD Group, LLC, as assignee of certain investors named therein, certain other investors named therein and certain of our employees. Under the terms of the registration rights agreement, we have, among other things:

• agreed to use our diligent best efforts to effect up to two registered offerings upon request from TD Group, LLC;

• agreed to use our best efforts to qualify for registration on Form S-3, following which TD Group, LLC will have the right to request up to three registrations on Form S-3; and

• granted incidental or "piggyback" registration rights with respect to any registrable securities held by any party to the registration rights agreement.

Our obligation to effect any demand for registration by TD Group, LLC is subject to certain conditions, including that the registrable securities to be included in any such registration have an anticipated aggregate offering price in excess of $15 million (in the case of any demand for registration other than a demand for registration on Form S-3) and $10 million (in the case of any demand for registration on Form S-3). In connection with any registration effected pursuant to the terms of the registration rights agreement, we will be required to pay for all of the fees and expenses incurred in connection with such registration, including registration fees, filing fees and printing fees. However, the underwriting discounts and selling commissions payable in respect of registrable securities included in any registration will be paid by the persons including such registrable securities in any such registration. We have also agreed to indemnify persons including registrable securities in any registration affected pursuant to the terms of the registration rights agreement and certain other persons associated with any such registration, in each case on the terms specified in the registration rights agreement.

Lease for Skurka Aerospace Inc.

Skurka, a wholly-owned subsidiary of TransDigm Inc., is the tenant under a lease with a company in which Howard Skurka, President of Skurka, is an owner. Together with family members, Mr. Skurka owns 100% of H & M Properties, the lessor of the property located in Camarillo, California. The term of the lease is five years from its December 2004 commencement, although it may be sooner terminated by Skurka if Howard Skurka's employment with Skurka were terminated by Skurka for cause or voluntarily by Howard Skurka without good reason. The monthly base rental payment for the property is $50,500. Skurka may renew the lease for an additional five years, subject to an adjustment to the monthly base rental for the extended period to $54,000. TransDigm Inc. is a guarantor of Skurka's obligations under the lease.

Recent Transactions

On November 10, 2005, TD Group completed the transactions contemplated by the TD Group Loan Facility and, in connection therewith, TD Group received net proceeds of approximately $193.9 million. In connection with the closing of the transactions contemplated by the TD Group Loan Facility, TransDigm Inc. paid a cash dividend of approximately $98.0 million to TransDigm Holdings and made bonus payments of approximately $6.2 million, in the aggregate, to certain members of management, including the named executive officers. TransDigm Holdings used all of the proceeds received by it from TransDigm Inc. to pay a cash dividend to TD Group. On November 10, 2005, TD Group used the net proceeds received upon completion of the transactions contemplated by the TD Group Loan Facility, together with substantially all of the proceeds received from the dividend payment from TransDigm Holdings, to:

• prepay the entire outstanding principal amount and all accrued and unpaid interest on the Senior Unsecured Promissory Notes, with all such payments totaling approximately $262.7 million;

• make distributions to certain members of our management who participated in the Rollover Deferred Compensation Plan of their vested deferred compensation account balances (including Mr. Peacock, a director, who participated in the Rollover Deferred Compensation Plan as the former chief executive officer of TransDigm Inc. and TransDigm Holdings), with all such distributions totaling approximately $23.0 million; and

• make distributions to certain members of our management and one of our directors who participated in the Management Deferred Compensation Plan of their vested and a portion of their unvested deferred compensation account balances, with all such distributions totaling approximately $3.0 million (with approximately $1.8 million of such distributions being attributable to vested deferred compensation account balances and approximately $1.2 million being attributable to unvested deferred compensation account balances). The amount of the unvested portion of the deferred compensation paid under the Management Deferred Compensation Plan constituted one-half of each participant's deferred compensation account balance, discounted by a factor determined by TD Group.

The approximately $6.2 million in aggregate bonuses were allocated to each employee receiving a bonus based on the aggregate number of shares of our common stock underlying rollover options and new management options granted to such employee in relation to the aggregate number of shares of common stock underlying rollover options and new management options granted to all employees receiving a bonus. Of the approximately $26.0 million distributed on account of vested and unvested deferred compensation account balances and the approximately $6.2 million distributed as bonuses, our executive officers and directors received the following amounts: (See page 90 of 424B4 for information).