I'm not sure if they will let you do the bubblewrap on the outside. Be sure your case locks and instead of checking it in you should be able to hand it off to the airline folks just before you get on the plane, at the gate. The same way people do baby strollers and such. You may also want to slack the strings a bit to reduce neck tension in case of too much turbulance or the airline tossing your guitar around like a football, you know how they are.