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Comment by underseacables | Hacker News Reader

Is that what happenes when The fan blades fly off and hit the airplane?

Pieces on the inside of jet engines are spinning between 2,000 and 12,000 rpm. They should all be properly contained in an airliner, but before that was the case of one fan blade broke and hit the plane it could look like a bomb blew an enormous hole in the side of the plane. These small pieces have a huge kinetic energy because they’re spinning so fast.

Nothing bad happening, everyone uninjured and a plane making an orderly airport emergency landing is many layers of safety systems all working properly.

Hull penetration at altitude can lead to explosive decompression, and, depending on the specifics of the penetration, complete hull loss.

Airplanes are big fragile inflated sausages, and it takes relatively little by way of explosive to down one. An early model (the de Havilland Comet, operated by BOAC and South African Airways in the 1950s) was downed due to a design flaw leading to metal fatigue around the windows, with three aircraft lost in 12 months due to in-flight break-ups, 99 souls lost.

Even at lower altitudes, an uncontained fan or turbine failure can be rough on the cargo or passengers, either from direct shrapnel, decompression, or (partial or full) egress.

https://www.bbc.com/news/world-us-canada-43803340

As ever, more detail and clear explanations on pprune[0].

As one commenter put it, to an ER doctor this is a shallow wound with lots of blood.

[0] https://www.pprune.org/rumours-news/638797-united-b777-uncon...

Most of the "skin" of a plane is only a few mm thick [0] it doesn't take much to puncture, I mean, it does, but thin turbine blades made to resist birds impact at 10k rpm would cut through it like butter.

[0] https://aviation.stackexchange.com/questions/45566/how-thick...

That’s almost exactly what happened on Southwest 1380[0] a few years ago.

[0]: https://en.wikipedia.org/wiki/Southwest_Airlines_Flight_1380

To add to the topic, aircraft structure and systems are made to withstand the projection of those debris hitting with "infitite" energy. That means for every trajectory possible, it's considered that a part flies through everything in its path. The aircraft still has to land.

The wing is an exceptionally strong component of the aircraft. It’s usually the freak accidents where you hear of a fuel tank being ruptured or control or hydraulic lines being cut. In all of these accidents I bet there is wing damage but the plane is able to continue as usual

WW2 fighter planes anyone?

Ugh look up QF-72 for an A380 Rolls-Royce engine containment failure...

Are you sure? That was an A330, and a failure on one ADIRU.

Aaaaaah always mixing this and QF-32 :-( sorry. The book by Richard de Crespigny is a must read if you can find it. Great.

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