Squeak, interestingly enough, I once asked my Rabbi about flying on Shabbos.
He said it is allowed, so long as you are on the plane before Shabbos. He said when you land, you are allowed to disembark, but at that point you have to wait to leave the airport until Shabbos is over. No, I’ve never flown on Shabbos, it was more theoretical than anything else.
I can’t see how it would be any different than being on a ship on Shabbos (which is certainly allowed).
The only real difference is that many sea voyages take longer than seven days, so being on board on Shabbos is required if you are going to take the trip. For air travel, that obviously isn’t the case, and therefore you shouldn’t schedule a flight for Shabbos. But if you’re on a flight for whatever reason on Shabbos, I can’t see it being any different than being on a ship.
The Wolf