TransDigm Group INC — Director's Dealing 2013

May 1, 2013

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: TransDigm Group INC (TDG)
CIK: 0001260221
Period of Report: 2013-04-29

Reporting Person: Howley W Nicholas (Director, Chief Executive Officer)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2013-04-29	Common Stock	M	7641	$6.68	Acquired	7641	Direct
2013-04-29	Common Stock	S	7341	$144.7468	Disposed	300	Direct
2013-04-29	Common Stock	S	300	$145.42	Disposed	0	Direct
2013-04-29	Common Stock	M	253	$13.37	Acquired	253	Direct
2013-04-29	Common Stock	S	253	$145.1675	Disposed	0	Direct

Derivative Transactions

Date	Security	Exercise Price	Code	Shares	A/D	Expiration	Underlying	Ownership
2013-04-29	Stock Option	$6.68	M	7641	Disposed	2013-08-05	Common Stock (7641)	Direct
2013-04-29	Stock Option	$13.37	M	253	Disposed	2013-08-05	Common Stock (253)	Indirect

Footnotes

F1: Price reported constitutes the average weighted price of shares sold. Shares were sold at varying prices in the range of $144.19 - $145.14. The reporting person hereby undertakes, upon request of the Commission, the issuer or a security holder of the issuer, to provide full information regarding the number of shares sold at each separate price.

F2: Price reported constitutes the average weighted price of shares sold. Shares were sold at varying prices in the range of $145.20 - $145.55. The reporting person hereby undertakes, upon request of the Commission, the issuer or a security holder of the issuer, to provide full information regarding the number of shares sold at each separate price.

F3: Price reported constitutes the average weighted price of shares sold. Shares were sold at varying prices in the range of $144.97 - $145.37. The reporting person hereby undertakes, upon request of the Commission, the issuer or a security holder of the issuer, to provide full information regarding the number of shares sold at each separate price.