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Air France A380 over Greenland on Sep 30th: Fan and engine inlet separated

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Re: Air France A380 over Greenland on Sep 30th: Fan and engine inlet separated

#31

Post by einrealist »

nabla9 wrote: post #2

It's more than just fan blade failure. Engines are tested against fan blade failures. The surrounding cowling should contain it. In this case the whole fan disk is gone. Uncontained failure like this can down the plane depending on the where the parts fly.

The fan failure was probably contained by the cowling. But the cowling broke right after because of stresses imposed by the damage and wind. If that's so, the cowling worked. The inner fans look damaged, so I assume the outer fan particles flew through the engine like expected.

Re: Air France A380 over Greenland on Sep 30th: Fan and engine inlet separated

#33

Post by hexane360 »

WalterBright wrote: post #7
nabla9 wrote: post #2

It's more than just fan blade failure. Engines are tested against fan blade failures. The surrounding cowling should contain it. In this case the whole fan disk is gone. Uncontained failure like this can down the plane depending on the where the parts fly.

For what a failing fan disk can do: https://en.wikipedia.org/wiki/United_Airlines_Flight_232

*For what a failing fan disk could do to a DC-10 built in 1973. Since this accident, hydraulic fuses and backup electronic actuators have become standard.

Re: Air France A380 over Greenland on Sep 30th: Fan and engine inlet separated

#34

Post by gnarbarian »

myth_buster wrote: post #32

Are there any serious dangers of debris falling over settlements in scenarios like these?

When you consider the frequency of incidents like this and factor in how sparsely populated most of the world is you'd have far better odds winning the lottery.

Re: Air France A380 over Greenland on Sep 30th: Fan and engine inlet separated

#35

Post by hexane360 »

tsomctl wrote: post #29
cycrutchfield wrote: post #28

Earlier quoted context omitted.

Typically, fan blades failing are due to metallurgical defects during manufacturing. Not sure where you are getting poor servicing from.

The conclusion of United Airlines Flight 232 was that although it was a manufacturing defect, the maintenance crew should have noticed the crack. Normally, cracks slowly spread over time until the part catastrophically fails, giving you time to catch it using various techniques (ultrasound, x-ray, penetrating dyes). https://en.wikipedia.org/wiki/United_Airlines_Flight_232

I'm not sure why you think it's reasonable to extrapolate the conclusion from an accident with a 1973 plane to an accident with modern hardware and vastly different fan materials. UA232 had a titanium alloy fan disk, while modern turbofans tend towards a nickel superalloy, sometimes even a single crystal.

Re: Air France A380 over Greenland on Sep 30th: Fan and engine inlet separated

#36

Post by userbinator »

nabla9 wrote: post #2

It's more than just fan blade failure. Engines are tested against fan blade failures. The surrounding cowling should contain it. In this case the whole fan disk is gone. Uncontained failure like this can down the plane depending on the where the parts fly.

Indeed, you could say that the front fell off. That's not very typical.

Re: Air France A380 over Greenland on Sep 30th: Fan and engine inlet separated

#37

Post by noobermin »

userbinator wrote: post #36
nabla9 wrote: post #2

It's more than just fan blade failure. Engines are tested against fan blade failures. The surrounding cowling should contain it. In this case the whole fan disk is gone. Uncontained failure like this can down the plane depending on the where the parts fly.

Indeed, you could say that the front fell off. That's not very typical.

I know we're not supposed to upvote or acknowledge jokes on HN, but this was in such good taste I couldn't resist.

Re: Air France A380 over Greenland on Sep 30th: Fan and engine inlet separated

#39

Post by hrrsn »

userbinator wrote: post #36
nabla9 wrote: post #2

It's more than just fan blade failure. Engines are tested against fan blade failures. The surrounding cowling should contain it. In this case the whole fan disk is gone. Uncontained failure like this can down the plane depending on the where the parts fly.

Indeed, you could say that the front fell off. That's not very typical.

For anyone that didn't get the reference, https://www.youtube.com/watch?v=3m5qxZm_JqM. Worth a watch!

Re: Air France A380 over Greenland on Sep 30th: Fan and engine inlet separated

#40

Post by mhh__ »

hrrsn wrote: post #39
userbinator wrote: post #36

Earlier quoted context omitted.

Indeed, you could say that the front fell off. That's not very typical.

For anyone that didn't get the reference, https://www.youtube.com/watch?v=3m5qxZm_JqM . Worth a watch!

RIP John Clarke :(
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