Exhibit 12

L-3 Communications Holdings, Inc.

and L-3 Communications Corporation

Ratio of Earnings to Fixed Charges

	Year Ended December 31,
	2011			2010			2009			2008			2007
	(In millions, except ratio of earnings to fixed charges)
Earnings:
Income from continuing operations before income taxes	$	1,328		$	1,484		$	1,386		$	1,423		$	1,165
Less: Net income attributable to noncontrolling interests		12			11			10			11			9
Income before income taxes after noncontrolling interests	$	1,316		$	1,473		$	1,376		$	1,412		$	1,156
Add:
Interest expense		226			257			268			279			304
Amortization of debt expense		9			12			11			11			10
Interest component of rent expense		55			59			59			58			56
Earnings	$	1,606		$	1,801		$	1,714		$	1,760		$	1,526
Fixed charges:
Interest expense	$	226		$	257		$	268		$	279		$	304
Amortization of debt expense		9			12			11			11			10
Interest component of rent expense		55			59			59			58			56
Fixed charges	$	290		$	328		$	338		$	348		$	370
Ratio of earnings to fixed charges		5.5	x		5.5	x		5.1	x		5.1	x		4.1	x