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by WalterBright 492 days ago
> it might be designed to rip off in this situation

It isn't on any aircraft I've heard of. Only the engines have "fuses" which allow an engine to rip itself off without taking the wing with it.

The wing root is the strongest part of the airplane (because that is where the maximum forces are).
2 comments
rdtsc 492 days ago
There are other parts like that, like the gear struts that are designed to bend and snap instead instead of puncture through the wings, or the centering mechanism on turbofan shafts that's intentionally designed to break off if a blade breaks and cause an imbalance (I think that's what you meant by a "fuse", or did you mean something that rips the engine off altogether? I had never heard of that one).
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WalterBright 492 days ago
The "fuse" that holds the engine on the strut is a bolt or a pin that is weaker than the surrounding structure, so it will break first and the engine will fall free.

If the engine loses a fan blade, it will vibrate violently and it's probably better to lose the engine.

I don't know about the other two things you mention. Maybe it's a newer feature than my time :-/

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rdtsc 491 days ago
> If the engine loses a fan blade, it will vibrate violently and it's probably better to lose the engine.

That's the idea with a fan blade loss, they didn't want to just drop an engine in that case so the centering mechanism on the turbine has an intentionally weaker part is designed to snap off to allow the spinning turbine to recenter itself as opposed to vibrating the whole structure off and causing more damage.

The gear thing is to prevent puncturing the fuel tanks in the wings on a hard landing. It's preferable to snap off the gear, otherwise leaking fuel has a good chance of it immediately igniting.

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michaelt 491 days ago
Small RC model planes often have the wings only loosely held on, such as by elastic bands, anticipating that the kids flying them will send them pinwheeling into the ground a few times while learning to operate them.

But yes, in a full size passenger aircraft I would expect the specification for wings falling off to say "avoid"

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WalterBright 491 days ago
There's no situation in flight where you'd want the wings to fall off to save the airplane!
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