The pilots were not making an 'absurd error'. They did not forget to fly the plane.
It is that what they thought they were doing was not what they were actually doing. Their mental model broke away from the reality. (They thought the plane was in 'normal mode' when it was actually in 'abnormal mode' -- an expression of which: one them declaring "this cannot be happening!")
Telling them just fly the airplane is not (quite) the solution -- they thought they were flying it.
But the remedy is sort-of basically correct. It just seems better expressed as: when nothing makes sense (your mental model has suddenly utterly failed), fall back to a more basic backup mental model and system -- like primitive manual override.
(How clear can such separation of a basic mode be? How practical would it be? How reliable? It leads to a set of engineering/UI questions . . . were they well designed in this particular case?)
I'm not so sure. They weren't flying the airplane, but rather were letting the computer fly it for them. (The control movements made by the one pilot who was horribly in error were not something that one would ever make if the controls were directly connected to the control surfaces.) Meanwhile, the computer was letting the humans fly. If the pilot in error had flown the airplane instead of driving the computer, everything would have come out fine. (And, while I'm not completely familiar with the Airbus's fly-by-wire system, I'm pretty sure that doing this still would have been safe in the event that the computer hadn't given up, either.)
They spent all this time trying to figure out what was wrong with the plane when their immediate concern should have been to get the nose down and get their airspeed up. Figuring out the underlying problem can wait. That's what "fly the airplane" is all about. Even if stuff is on fire, the first priority is to keep your speed up and don't run into anything hard.
The problem is they did not know there airspeed and they did not understand they where stalling. The airspeed issue related to simple icing. Stalling was a little more complex than that. They had plenty of indications that they where stalling one of the pilots simply did not believe them.
Aside: Using the word "simply" glosses over the interesting bits.
Why did a pilot, a 32 year old, with Air France for 4-5 years, qualified to fly the A330 (for 2 months), with "under 3,000 hours of experience" [NYTimes] (so, a couple of thousand hours) not believe the stall warning? And what can humans do to guard against that?
That's an interesting question, "simply" doesn't do it justice.
Doesn't matter. You're descending at 10,000fpm. Your nose is up. This is wrong, no matter what else is going on. First order of business: point the nose in the same direction that the airplane is actually flying. Everything else can wait.
The pilots were not making an 'absurd error'. They did not forget to fly the plane.
It is that what they thought they were doing was not what they were actually doing. Their mental model broke away from the reality. (They thought the plane was in 'normal mode' when it was actually in 'abnormal mode' -- an expression of which: one them declaring "this cannot be happening!")
Telling them just fly the airplane is not (quite) the solution -- they thought they were flying it.
But the remedy is sort-of basically correct. It just seems better expressed as: when nothing makes sense (your mental model has suddenly utterly failed), fall back to a more basic backup mental model and system -- like primitive manual override.
(How clear can such separation of a basic mode be? How practical would it be? How reliable? It leads to a set of engineering/UI questions . . . were they well designed in this particular case?)