Stow your tray tables and return your seat back to its full, upright position, because this one's a doozy: Starting this fall, many of the seats in new airplanes will feature airbags designed to inflate in the event of an "irregular" landing.

It's part of a new set of rules that go into effect on October 27, designed to raise the durability of airplane seats to help passengers survive crash landings. Many of the seats we currently sit in while airborne are required to withstand only 9 times the force of gravity (9G). New seats will have to absorb the shock of a 16G hit.

The new rule affects all newly produced planes, regardless of the model. (Previous rules required 16G seats but only if the model had been introduced after 1988, exempting hundreds of jets, including the Boeing 747, from the rules.) Older planes will not have to be retrofit with the seats.

The reason for the seat upgrades is interesting, as it turns out that many airplane crashes are survivable -- so long as the passenger remains alert and conscious after the plane comes to a stop. If the plane is on fire or filling with smoke, it's important that passengers can get off the plane quickly, hence the upgraded seats and airbags.

Airbags won't appear in every seat, only those where the seat in front is too far away to function as a cushion. Built into the lap belt, they're mainly being placed in first class cabins, exit rows, and behind bulkheads.

That may come in handy if the infamous Ryanair gets it way: Its latest plan is to replace standard seats with what it calls "bar stools," in order to pack more people (up to 50 percent more, potentially) on each plane. Though that plan requires regulatory approval from the Irish Aviation Authority, where Ryanair is subject to regulation, a spokesman has said that formal approval is the only thing in the way of proceeding with the idea.

Oh, and don't forget your change, either: Ryanair wants to install pay toilets on its flights, too.