I still wouldn't take the chance with my birds. Flight delays, mishandling of luggage, LOSS of luggage, just happens too often with air travel. Flat rate UPS for 75# and under is not that expensive when compared to the risk of flying it with you. The last time I flew out of O'Hare (connected there from BWI) for a Bow hunt Elk (long time ago) I watched them (had a window seat right above where they unloaded luggage and cargo) throw my $1200 dollar rig around like a bag of rocks. It was marked FRAGILE on both sides clearly. I watched it hit the ground TWICE before the idiot got it onto the carrier! Glad I spent the extra bucks on a really sturdy hard case! Filed a complaint with United with the passenger that was sitting next to me signing as witness. Got a really polite "screw off we don't care" for my trouble. Case was dinged up from the tarmack but the sites and everything were okay.