FORM 4 Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 STATEMENT OF CHANGES IN 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

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(Print or Type Responses)

1. Name and Address of Reporting Person * SKALABRIN MARK F   2. Issuer Name and Ticker or Trading Symbol MERCURY COMPUTER SYSTEMS INC [MRCY] 5. Relationship of Reporting Person(s) to Issuer (Check all applicable) _____ Director _____ 10% Owner __X__ Officer (give title below) _____ Other (specify below) VP & GM Advanced Solutions (Last) (First) (Middle) 175 CRANE NECK ROAD 3. Date of Earliest Transaction (Month/Day/Year) 09/11/2006 (Street) WEST NEWBURY, MA 01985 4. If Amendment, Date Original Filed(Month/Day/Year) 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 Acquired, Disposed of, or Beneficially Owned

1.Title of Security (Instr. 3) 2. Transaction Date (Month/Day/Year) 2A. Deemed Execution Date, if any (Month/Day/Year) 3. Transaction Code (Instr. 8) 4. Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5) 5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4) 6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4) 7. Nature of Indirect Beneficial Ownership (Instr. 4) Code V Amount (A) or (D) Price Common Stock 09/11/2006   A   7,500 A $ 0 (1) 72,044 D

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Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned
(e.g., puts, calls, warrants, options, convertible securities)

1. Title of Derivative Security (Instr. 3)

2. Conversion or Exercise Price of Derivative Security

3. Transaction Date (Month/Day/Year)

3A. Deemed Execution Date, if any (Month/Day/Year)

4. Transaction Code (Instr. 8)

5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4, and 5)

6. Date Exercisable and Expiration Date (Month/Day/Year)

7. Title and Amount of Underlying Securities (Instr. 3 and 4)

8. Price of Derivative Security (Instr. 5)

9. Number of Derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)

10. Ownership Form of Derivative Security: Direct (D) or Indirect (I) (Instr. 4)

11. Nature of Indirect Beneficial Ownership (Instr. 4)

Code

V

(A)

(D)

Date Exercisable

Expiration Date

Title

Amount or Number of Shares

Employee Stock Option (right to buy)

$ 30.063

09/11/2006

D

15,000

10/10/2001(2)

10/10/2010

Common

15,000

$ 0 (3)

0

D

Employee Stock Option (right to buy)

$ 37.15

09/11/2006

D

15,000

10/15/2002(4)

10/15/2011

Common

15,000

$ 0 (3)

0

D

Reporting Owners

Reporting Owner Name / Address	Relationships
	Director	10% Owner	Officer	Other
SKALABRIN MARK F 175 CRANE NECK ROAD WEST NEWBURY, MA 01985			VP & GM Advanced Solutions

Signatures

Craig Barrows, Attorney-in-fact		09/12/2006
**Signature of Reporting Person		Date

Explanation of Responses:

*	If the form is filed by more than one reporting person, see Instruction 4(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)	On September 11, 2006, Mercury Computer Systems, Inc., cancelled, pursuant to its option exchange program, options granted to the reporting person on October 10, 2000 and October 15, 2001. In exchange the reporting person received a restricted stock award covering 7,500 shares which vests as to two-thirds of the covered shares on September 11, 2008 and one-third of the covered shares on September 11, 2009.
(2)	The cancelled option provided for vesting in four equal installments commencing on October 10, 2000. On June 20, 2005 the Company fully accelerated the vesting of this option.
(3)	Field N/A to this transaction but was completed to allow for electronic filing only.
(4)	The cancelled option provided for vesting under certain performance criteria. On June 20, 2005 the Company fully accelerated the vesting of this option.

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