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Comment by outworlder | Hacker News Reader

Improbable unless it's a really enormous bird (or many large birds at one time). A chicken wouldn't be big enough. Bird ingestion would probably cause some damage that would have to be repaired, but jet engines are tested for this exact scenario. And engines are tested for large birds and both medium and small engine flocks.

Sure, it _could_ happen with a single bird, but it probably won't.

https://www.law.cornell.edu/cfr/text/14/33.76

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Engines are also tested for speeds and altitudes where birds are typically encountered - ie, not Mach 0.8 at FL35. Canopy tests are similar.

If I’m remembering correctly, I think the typical “speed limit” is 250 kts below Class A airspace, which is a far cry from a Mach number.

edit: I also recall that the testing allows for destruction of the engine as long as shrapnel does not penetrate the fuselage. Engines are not happy ingesting a goose regardless of speed or altitude. There’s a liner surrounding the turbine blades the must remain intact to pass the test.

I'm sure that Sully flight is much more confident that they didn't crash due to dual engine loss from bird strike thanks your comment.

To pile on, the average weight of male Canadian Geese is > 8 pounds, which is higher than the largest 'large bird' that needs to be tested, and they travel in flocks. I think they worked out that each engine probably ingested two birds. At the time those engines were certified, the largest bird tested was 4 lbs and they only volleyed them into the outer area of the engine, not the core where the accident engines hit.[1]

Now they have to send them into the 'most critical area' of the engine, but depending on engine size the largest bird tested could still be 4 or 6 lbs.

[1] https://www.ntsb.gov/investigations/accidentreports/reports/...

By "tested", do you mean someone out there has the somewhat insane job of throwing actual birds into fully-powered jet engines?

And I guess cleaning up afterward also?

They use a chicken gun, but yes… https://en.m.wikipedia.org/wiki/Chicken_gun

One of the timeless mythbuster bits too.

Engines are tested exactly for the scenario of ingesting a small bird, yes.

Not for ingesting a large Mylar balloon with a mass tied to one end, necessarily.

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