I'm not a pilot, however, most pilots (and many flight attendants) in many US carriers use Purdy Neat roller bags -- here's a link (caveat: I could not see on the site if they ship outside of the US, but it seems likely that they do not):
http://www.stopoverstore.com/product...m/pnid/1/nid/2
I've had the 22" metal frame roller bag since October 1997 and it has needed repairs... twice? And I was not precious with it. I've had the outer frame replaced (unusual, as the metal is quite strong; it somehow got bent after I checked it nonrevving), the main zipper replaced, the handle replaced, and new wheels put on. Very normal repairs for 10 years of service IMO. I would recommend this bag over any other bags. V v sturdy and worth the money.