Rockwell Collins reported a big drop in its commercial aftermarket sales in the past year, but keep in mind this includes business jets, too (not just services for airline-category aircraft).

In its earnings statement for the company's fiscal year, which ended Sept. 30, Rockwell Collins says, "Aftermarket sales decreased $60 million, or 23%, to $205 million due primarily to lower retrofit and spares sales and reduced avionics service and support revenues for both airlines and business jet operators. Sales of wide-body in-flight entertainment products and systems decreased $19 million, or 44%, to $24 million compared to the prior year period. "