Commitments (Tables)

3 Months Ended

12 Months Ended

Jul. 31, 2012

Apr. 30, 2012

Summary of operating leases

The minimum lease rentals required under operating leases are payable in the following amounts over the following fiscal years:

	Aircraft operating leases		Building, land and equipment  operating leases		Total operating leases
2013	$	207,661	$	8,471	$	216,132
2014		186,978		7,130		194,108
2015		171,409		6,165		177,574
2016		151,911		4,676		156,587
2017		126,841		4,080		130,921
and thereafter		339,481		60,366		399,847
	$	1,184,281	$	90,888	$	1,275,169

The minimum lease rentals required under such leases are payable in the following amounts over the following fiscal years:

	Aircraft operating leases		Building, land and equipment operating leases		Total operating leases
2013	$	209,352	$	8,112	$	217,464
2014		184,249		7,222		191,471
2015		165,130		5,894		171,024
2016		147,580		4,668		152,248
2017		124,055		3,888		127,943
Thereafter		356,090		61,112		417,202
	$	1,186,456	$	90,896	$	1,277,352