I recently have been doing a lot of traveling with Ampeg and need to carry a bass with me on most of my flights. I usually have no problem carrying my bass on airlines in a Reunion Blues Leather Bag. I use this bag because it's very unassuming and has no buckles or metal on it other than a small clasp and the zippers. Even after 911, most airlines are pretty cool about carry an instrument on board but....
There's always the chance that you get to a plane that has very small overheads and I've had to "gate check" my bass. The thought of someone else handling my gig bag can be scary. Plus even if you are traveling on a plane that does accomodate, you always run the risk of some jerk trying to stuff his or her oversize carry-on into the same overhead. Or dealing with gate attendants that want to give you a hard time. Or you just plain don't want to carry a bunch of stuff on board.
The SKB Bass Safe is the answer to your dreams!!!!!! This case allows you to check your instrument in an ATA Flight approved case and it allows you to carry it in its gig bag. So when you get to your hotel or destination, you can pull it out of the case and travel with it in its gig bag. I highly recommend that if you are planning on doing a bunch of air travel, you should check this thing out.
Click on the SKB logo for a link to the Bass Safe Webpage

Recent global developments have given rise to many concerns for airline travelers, especially for the emotional attachment to the cargo of the traveling musician.
SKB’s engineering team has addressed these travel issues with a bold innovated design, and futuristic molding techniques for the new 1SKB-44RW ATA Electric Bass Safe.
SKB’s rotationally molded rolling Bass Safe introduces a brand new concept and loading technique. Your bass is inserted, Gig Bag and all, into this indestructible airline safe shell, the two halves slide together, quick latch, padlock if you desire, then tip it up and roll away. This is just the beginning of a revolution in instrument travel protection.
SPECIFICATIONS:
Model No. SKB-44RW
Overall Length: 48 1/2"
Body Depth: 4 3/4"
Lower Bout: 16 3/4"
Weight: 13.2 lbs.
WARRANTY:
lifetime