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Comment by goodcanadian | Hacker News Reader

Yes, I am always slightly annoyed by findings of pilot error. It is not that the finding is wrong, but the terminology leads the general public to blame the pilot when the reality is usually that the error was due to the pilot having misleading, incomplete, or just plain wrong information, or the controls behaving in a non-intuitive manner or whatever.

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I suppose after watching this show, I now understand it better. But I now realize that pilot error is never just pilot error. Without some other failure or extraordinary circumstance, pilots have a damn hard time crashing a plane on their own.

With the sad exception of the Germanwings flight.

And the EgyptAir flight and the SilkAir flight if you're going to count deliberate pilot actions. (https://en.wikipedia.org/wiki/Suicide_by_pilot#By_pilots_in_...)

But Air France 447 is a recent example where it's really tempting to say that sheer pilot incompetence was the biggest factor: https://en.wikipedia.org/wiki/Air_France_Flight_447

Yes, I think they were definitely incompetent in the AF case. It's fair to question if their incompetence is a result of poor training by AF, but not recognizing a stall very squarely falls into "incompetent" IMO.

I think that's too harsh. The pilot applied what would be appropriate for "normal law" (full fly-by-wire). Unfortunately the plane was in "alternate law", where pulling the stick was the wrong thing to do. I would blame the incident partly to bad user interface and to the fact that the appropriate action is the opposite in normal and alternate law if the plane stalls (whoever came up with thinking this was a good idea). Even worse, the second pilot can't "feel" on the stick what the first pilot does.

A stall horn is hard to overhear.

Understanding what alternate law is as an airbus pilot is a very basic requirement.

>appropriate action is the opposite in normal and alternate law

I'm not sure what you are referring to here, but the fact that the appropriate action was to push forward to bring the nose down was the same regardless of alternate law/normal law. The bad UI was that the stall alarm shut off when the stall became so severe, which is why the pilots pulled up to stop the stall alarm (making the stall worse).

>Even worse, the second pilot can't "feel" on the stick what the first pilot does.

The system warns on dual input when it conflicts like that. Again, recognizing this condition is a very basic requirement of understanding the airbus control system. Regardless of that, the pilots did not communicate what they thought the problem was and what they were doing to solve it. Competent pilots don't end up in a situation where one is silently doing the opposite of the other and they don't realize it.

I think you're very right, and we shouldn't get into an Airbus-vs-Boeing discussion here.

Nevertheless, I wonder whether that particular accident would have happened with the physical link between yokes, rather than the side sticks; and whether there are lessons to be learned from that regarding UI/human-system-interface.

But then, how idiot-proof should planes be...

I agree with you that the incident is clearly attributable to pilot error, maybe even incompetence. However when searching for details I came across this: https://flightsafety.org/asw-article/stop-stalling/

I am convinced that much of human error is due to bad user interface, especially in technical settings. I think it is an important lesson that both pilots failed to recognize (in a stressful situation):

1. the plane was in alternate law 2. either actions contradicted each others

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