TransDigm (TDG) 10-K 2012 FY Annual report

Exhibit 12.1

TRANSDIGM GROUP INCORPORATED

COMPUTATION OF RATIO OF EARNINGS TO FIXED CHARGES

(Amounts in Thousands)

	Fiscal Year Ended September 30,
	2012		2011		2010		2009		2008
Earnings:
Total earnings from continuing operations	$	324,969	$	152,225	$	163,445	$	162,902	$	133,126
Income tax provision		162,900		77,200		87,390		88,100		73,476
Pre Tax Earnings		487,869		229,425		250,835		251,002		206,602
Fixed charges:
Interest charges		211,906		185,256		112,234		84,398		92,677
Interest factor of operating rents		2,602		1,959		1,398		1,095		1,052
Total fixed charges		214,508		187,215		113,632		85,493		93,729
Earnings as adjusted	$	702,377	$	416,640	$	364,467	$	336,495	$	300,331
Ratio of earnings to fixed charges(1)		3.3		2.2		3.2		3.9		3.2

(1) For purposes of computing the ratio of earnings to fixed charges, earnings consist of earnings before income taxes plus fixed charges. Fixed charges consist of interest expense, amortization of debt issuance costs and the portion (approximately 33%) of rental expense that management believes is representative of the interest component of rental expense.