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Planes are designed to land without or with partial landing gear. That's the redundancy.


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On small planes, landing gear is not retractable.

Landing gear?

I'm not involved with the airline industry in any way, but I would think that since landing gear is a highly mechanical, moving piece with plenty of failure points, airliners are probably designed with a margin of error to withstand gearless landings without loss of life.

It's incredibe the infrastructure these things have. A plane is so utterly dependent on having everything ready where it lands, which is why this emergency landing probably throws everything into disarray.

Strangely like an F1 car where they don't have a starter on the plane, they need an assist to get going.


As the plane gets older and less sophisticated it gets harder to put all the pieces of the puzzle together without ripping the whole aircraft to pieces and starting over.

Even after touching down, the aircraft this is built for have computer control for the brakes and full rudder authority, so it can do a pretty good approximation of a proper short field landing based on GPS and wheel speed sensors. Do you want to add computer controlled brakes and wheel speed sensors to your tin can? No? Then we have to assume the plan is to just roll to a halt and that cuts our list of viable landing sites and hurts survivability considerably.


Aren’t planes already designed for landing at full weight for cases where the plane needs to turn around and land where it departed?

More like landing gear.

You porpoise the landing. The front gear in just about every aircraft is not intended to take the weight that the rear can. End up in an unstable oscillation, until it gives.

https://www.youtube.com/watch?v=NMmHYWjEmkY


How does a plane lose its front landing gear?

Dumb question here: why don't airplanes incorporate weight sensors in the landing gear to eliminate this problem?

If you don't have to land with a full load of fuel it's better not to.

And there was no reason to think that the landing would go wrong, because the tires are redundant.


Most planes does have the ability to land themselves. This is called autoland.

Don’t the landing gear have sensors in them to measure how heavy the plane is?

That's not an automated landing system failure, that's a landing gear failure.

The difference with a plane, however, is it isn't necessary to fix it. It's just necessary to get it on the ground safely.

> planes don't need ground traction

They certainly do. First, they need it to get the pointy end airplane pointed in the right direction. Then, they need it until they are going fast enough for the rudder to work.


Most things in aircraft automation systems depend on sensors that could fail (those sensors could be redundant etc. but the same can be done with the sensors on landing gears). It is sane design.

> What if the landing gear don't drop?

I don't think that there is need for reverse thrust in such a scenario.

> Is there a situation where you would still want reverse thrust without landing gear?

Even if there is, there could be a manual override.


The Airbus A320 can't either. It's not required as long as the landing system is designed to handle the fully-loaded weight.

They could have installed remote control landing gear if they ever needed it.
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