I've mentioned it somewhere else before but- a couple of years ago Alaska Airlines, the only major line we have in Juneau, had been making a fuss about anyone carrying on an instrument. Then one day, our local concertmeister, Steve Tada, was told he had to check his violin. After much ado, the airline prevailed, the violin was taken from him and put in the hold, and Steve came home livid. He promptly wrote letters to everyone in power that he knew, including our governor at the time, Tony Knowles. Tony went to bat for him- and the upshot is that yes, you can now carry on any instrument smaller than a bass or a tuba.

I've carried on only a mandolin, given me by my brother before he died. He never had a case for it, just carried it in a bag and that's how it traveled to Juneau. The flight attendants were extremely careful with it- even rescued it from the overhead when someone else was going to put his own things in.