TransDigm Group INC — Director's Dealing 2012

May 1, 2012

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: TransDigm Group INC (TDG)
CIK: 0001260221
Period of Report: 2012-04-30

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

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2012-04-30	Common Stock	M	2500	$6.68	Acquired	2500	Indirect
2012-04-30	Common Stock	S	1800	$126.0094	Disposed	700	Indirect
2012-04-30	Common Stock	S	700	$126.9886	Disposed	0	Indirect
2012-04-30	Common Stock	M	33000	$6.68	Acquired	33000	Direct
2012-04-30	Common Stock	S	24420	$126.0353	Disposed	8580	Direct
2012-04-30	Common Stock	S	8480	$26.7488	Disposed	100	Direct
2012-04-30	Common Stock	S	100	$127.73	Disposed	0	Direct

Derivative Transactions

Date	Security	Exercise Price	Code	Shares	A/D	Expiration	Underlying	Ownership
2012-04-30	Stock Option	$6.68	M	2500	Disposed	2013-08-05	Common Stock (2500)	Indirect
2012-04-30	Stock Option	$6.68	M	33000	Disposed	2013-08-05	Common Stock (33000)	Direct

Footnotes

F1: Price reported constitutes the average weighted price of shares sold. Shares were sold at varying prices in the range of $125.56 - $126.23. 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 $126.73 - $127.70. 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 $125.58 - $126.57. 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.

F4: Price reported constitutes the average weighted price of shares sold. Shares were sold at varying prices in the range of $126.58 - $126.96. 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.