AAR Power Services S-4 Registration of securities issued in business combination transactions

Exhibit 12.1

											Three Months Ended
	For the Year Ended May 31,										August 31,
	2012		2011		2010		2009		2008		2012		2011
											(unaudited)
	(In Thousands Except Per Share Data and Ratios)
Earnings Available for Fixed Charges
Earnings before income taxes	$	93,203	$	103,407	$	65,614	$	86,249	$	105,340	$	27,908	$	25,419
Add:
Interest expense	36,247		28,143		25,532		30,225		28,366		10,058		7,054
Amortization of debt expense	1,831		2,524		1,301		1,191		1,125		543		464
One-third of rent expense under operating leases (estimated by management to be the interest factor of such rent expense)	9,993		9,284		7,744		7,548		6,207		3,038		2,309
Earnings available for fixed charges	$	141,274	$	143,358	$	100,191	$	125,213	$	141,038	$	41,547	$	35,246
Fixed Charges
Interest expense	36,247		28,143		25,532		$	30,225	$	28,366	$	10,058	$	7,054
Amortization of debt expense	1,831		2,524		1,301		1,191		1,125		543		464
One-third of rent expense under operating leases (estimated by management to be the interest factor of such rent expense)	9,993		9,284		7,744		7,548		6,207		3,038		2,309
Total fixed charges	$	48,071	$	39,951	$	34,577	$	38,964	$	35,698	$	13,639	$	9,827
Ratio of earnings to fixed charges	2.9		3.6		2.9		3.2		4.0		3.0		3.6