Ownership Submission
FORM 3
 UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

INITIAL STATEMENT OF BENEFICIAL OWNERSHIP OF SECURITIES

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934, Section 17(a) of the Public Utility Holding Company Act of 1935 or Section 30(h) of the Investment Company Act of 1940
OMB APPROVAL
OMB Number: 3235-0104
Expires: January 31, 2005
Estimated average burden hours per response... 0.5

(Print or Type Responses)
1. Name and Address of Reporting Person *
  Palmer Peter
 2. Date of Event Requiring Statement (Month/Day/Year)
02/15/2012		 3. Issuer Name and Ticker or Trading Symbol
TransDigm Group INC [TDG]
(Last)
(First)
(Middle)
1301 EAST 9TH STREET, SUITE 3710		 4. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
_____ Director _____ 10% Owner
__X__ Officer (give title below) _____ Other (specify below)
President, AdelWiggins Group
 5. If Amendment, Date Original Filed(Month/Day/Year)
(Street)

CLEVELAND, OH 44114		 6. Individual or Joint/Group Filing(Check Applicable Line)
_X_ Form filed by One Reporting Person
___ Form filed by More than One Reporting Person
(City)
(State)
(Zip)
Table I - Non-Derivative Securities Beneficially Owned
1.Title of Security
(Instr. 4)		 2. Amount of Securities Beneficially Owned
(Instr. 4)		 3. Ownership Form: Direct (D) or Indirect (I)
(Instr. 5)		 4. Nature of Indirect Beneficial Ownership
(Instr. 5)
Common Stock 0
D
 

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly. SEC 1473 (7-02)
Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB control number.

Table II - Derivative Securities Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security
(Instr. 4)		 2. Date Exercisable and Expiration Date
(Month/Day/Year)		 3. Title and Amount of Securities Underlying Derivative Security
(Instr. 4)		 4. Conversion or Exercise Price of Derivative Security 5. Ownership Form of Derivative Security: Direct (D) or Indirect (I)
(Instr. 5)		 6. Nature of Indirect Beneficial Ownership
(Instr. 5)
Date Exercisable Expiration Date Title Amount or Number of Shares
Stock Option (1) 10/01/2009 10/01/2015 Common Stock 17,468 $ 13.37 D  
Stock Option (2) 10/01/2011 10/01/2015 Common Stock 3,990 $ 13.37 D  
Stock Option (3) 10/01/2015 11/17/2018 Common Stock 35,000 $ 27.08 D  
Stock Option 04/22/2011 04/22/2020 Common Stock 10,000 $ 56.86 D  
Stock Option 11/14/2012 11/14/2021 Common Stock 10,500 $ 97.42 D  

Reporting Owners

Reporting Owner Name / Address Relationships
Director 10% Owner Officer Other
Palmer Peter
1301 EAST 9TH STREET
SUITE 3710
CLEVELAND, OH 44114		       President, AdelWiggins Group  

Signatures

/s/Halle F. Terrion, as Attorney-in-Fact for Peter Palmer 02/22/2012
**Signature of Reporting Person Date

Explanation of Responses:

* If the form is filed by more than one reporting person, see Instruction 5(b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations. See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
(1) Vest based on the achievement of annual and cumulative per share operating performance targets between fiscal 2009 and fiscal 2013.
(2) Vest based on the achievement of annual and cumulative per share operating performance targets between fiscal 2011 and fiscal 2015.
(3) Vest based on the achievement of annual and cumulative per share operating performance targets between fiscal 2015 and fiscal 2016.

Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, See Instruction 6 for procedure.

Potential persons who are to respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB number.