I definitely have a five year old’s understanding of aviation and engineering but I’m envisioning a system in which the wings/tail section are intentionally designed to break away in the event of a catastrophic failure, and a parachute deploys to carry just the fuselage back down at a safe speed.
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It’s general extremely rare for an aircraft to become entirely uncontrollable. It’s easier to design aircraft to avoid that situation than waste a lot of weight on a parachute recovery system that likely will never be used.
Cirrus airplanes employ parachutes on all their certified airframes. Comes standard on Pipstrel planes.
From General Aviation News: Numerous European and U.S. ultralight and experimental aircraft use the system, including Lancair, Carbon Cub, Kitfox, Glasair, Flight Design, Rans, Van’s RV 7/9/10, Kolb, Zenair, and Quicksilver. The BRS whole aircraft parachutes are available for light sport aircraft including
CTSW, CTLS, Piper Sport Cruiser, Cessna Skycatcher, Bristell, FK-9 and Icon A5. Certified General Aviation aircraft that fly with the system include Cessna 150, 152, 172, 182, and Symphony. It is standard equipment on the Cirrus SR20 and SR22.
it would make the plane a lot heavier. there’s tons of things to keep in mind, like that a plane usually travels at a much higher speed and will generate much higher forces so the chute will have to be much sturdier, well-connected, which again means more weight, more fuel used (for each trip! and how often would a plane need this, every 5000th trip maybe? 10000th?) and just generally more cost.
it is much more practical to have planes attempt to do a “controlled” gliding-landing which requires basically no additional features and will work in 99% of emergencies just as well if not better.
This one gets asked a lot.
Multiple reasons:
1 – planes tend to crash during takeoff and landing, too low to deploy a parachute.
2 – large commercial planes that drop out of the sky *drop* out of the sky, blown apart by some catastrophic failure or hostile action. There aren’t many cases where a plane is sort of crashing. Either they’re flying or they’re going down in a fireball of twisted aluminum and body parts.
3 – a 747 weighs 400,000 pounds, that’s a gigantic parachute you’re gonna need to haul around *every flight* for the 1-in-a-billion chance you may need it. It must also be unfolded and inspected periodically.
4 – some light propeller aircraft actually do carry a big parachute, it’s just not feasible for a much larger, heavier, and faster jet aircraft.
Astronauts have a lot of flexibility in their plans when the goal is “land from space”. Launch and landings tend to be pretty close to the ocean so that if something does go horribly wrong, you crash out at sea.
God forbid a regular aircraft suffer something so horrible and crash, but the last thing we want is MORE debris falling over a wider area in more urban settings. Crashes into cities are rare but they have happened. Mid-air break-ups are extremely rare but will result in destruction over a much wider area. Can we please **not** do that on purpose?
> I’m envisioning a system in which the wings/tail section are intentionally designed to break away in the event of a catastrophic failure
You generally don’t want the wings to be *able* to break away, because once they can do that you have to worry about them doing so at the wrong time. It’s better to have wings that will stay on *no matter what*.
Aside from that, there are several challenges. One is that an aircraft is quite a lot bigger and heavier. SpaceX’s Dragon capsule weighs around 10 tons on reentry. A modern commercial aircraft might weigh 20-50 tons on its own, but it probably has hundreds of passengers too, so the total weight is quite a lot higher.
The next problem is that parachutes are quite complex. You don’t just press a button and then they *magically* unfold in just the right way. With a spacecraft we can control the angle and speed and everything to make sure it is oriented correctly so the parachutes can unfold, but with an out-of-control plane we can’t predict what it’ll be doing. Is it spinning? Upside down? Falling sideways? Will the parachutes work in all these cases? Probably not.
But sure, we could put big clunky parachutes on every plane. But when was the last time an aircraft at normal cruising altitude suffered the kind of catastrophic failure where a parachute would help? It pretty much never happens. The thing about plane crashes is that they always happen at ground level. And the thing about parachutes is that they *don’t* really help if you’re already at or near ground level. You have to use them when you’re several kilometers up in the air, and at that altitude you’re probably not going to trigger them because the situation is not yet critical.
So sure, we could put parachutes on every aircraft, adding a significant amount of weight, increasing fuel consumption and perhaps lowering the number of passengers that can be carried. All of this would cost money, but we could do it. But why? Just to create a system which will virtually never be needed, and even if it *is* needed, it is so complex that it might not work, or the plane, having suffered some kind of catastrophic failure, is tumbling through the air in a way that the chutes get tangled up and everyone dies *anyway*.
This is a typical scenario that I experience at work everyday, since I have to create change.
1,000 reasons why it can’t be done.
Occasionally, one or two voices with solutions and possibilities.
The, “it happens rarely” comments made me laugh. If you were on the rare plane that was crashing, you’d wish you were more limitless forward-thinking, and solution oriented, at that moment.
A system called Ballistic Recovery, using parachutes, is available on a few small planes.
If you ask an aircraft designer and a statistician about using these on airliners, I’d bet they would say you would cause more overall deaths in transportation than you would save. Fatalities in U.S. Scheduled air carrier operations are essentially zero. If you exclude losses due to landing and departure, and sabotage or murder, you are left with a small handful of recoverable incidents. *Over the entire history of aviation.*
Actually, we can’t get astronauts back from orbit with only a parachute. The astronaut would burn up on re-entry before the parachute slowed him down. Perhaps you’re thinking of aircraft pilots.
Aircraft don’t use parachutes because there’s an upper limit to how many parachutes you can attach to an object. This is a function of surface area and surface area and mass tend to follow the squared-cubed law. Mass tends to grow faster than surface area. In short, the aircraft is so heavy that even if you covered the top of it with as many parachutes as would fit the aircraft would still land hard enough to turn to scrap.
Also, when a pilot eject from an aircraft, that aircraft is usually on fire. No point in trying to save it.
Most commercial air planes are aerodynamically efficient and can glide in low or no power conditions… this is also the only practical situation where parachute(s) will be usefull.
For any other scenarios, like mentioned else where it’s either too low for deployment or the parachute will only help land a fireball if not already consumed by it.
Also economics play a major part… regular inspection and maintenance of such mechanism may increase the operational costs, but not necessarily a hinderence.
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