azflyboy posted:

The physics involved make fitting a parachute to an airliner pretty much impossible.

The system Cirrus uses has to be deployed below about 140 knots, in an airplane that weighs no more than 3600 lbs. Even a small airliner is going to weigh somewhere between 40 and 60,000 lbs, and will be flying in excess 250kts for much of a given flight. Doubling the speed of an object means it has four times more energy to bleed off (to say nothing of the fact that the airliner weighs at least 10 times more than the Cirrus), so a parachute that could safely decelerate even a small airliner from anything faster than approach speed would have to be massively heavy and complex, and there are very few situations where it would be of any use.

When you scale up to something like a 747 (which can weigh over 900,000 lbs on takeoff), an airframe parachute becomes basically impossible, unless you want to start jettisoning things like the wings and tail while deploying the parachutes, which opens up a bunch of other avenues for things to go catastrophically wrong.