4 ms·
Critically in that case, the stall warning stopped when the nose was pulled up even further, because the computers rejected the indication as too large to be co
by danaliv 7y ago
Critically in that case, the stall warning stopped when the nose was pulled up even further, because the computers rejected the indication as too large to be correct. So every time the nose was lowered, the stall warning activated.
- inflatableDodo 7y agoFucking hell. That is a fucker of a dark UX pattern.
- danaliv 7y agoIndeed. And it goes to show that rejecting “impossible” values is a dangerous strategy.
- inflatableDodo 7y agoI think you can reject impossible derivatives, though only if being very fucking careful.
- shawnz 7y agoLet's say you notice a sudden change in a sensor which is surely not physically possible. Was the value more accurate before or after the sudden change? Do you reject the current actual value or the dead-reckoned value based on the old data?
- salex89 7y agoAF447 is really a terrible accident, just hard to analyze. It's not even clear would breaking one link in the chain save the plane, since so many thing happened. True, UX was inadequate. But there was one more detail, the indications were incorrect and mismatched for a short period, while the pilot inputs were continual. It's not hard to interpret that the pilot actually knows something you don't (speaking from the computer's POV) and disengage ("Wait, we're 40 degrees pitch-up, and the man keeps pulling up, alternate flight law engaged, sensors might be incorrect, listen to the man").
- FabHK 7y agoSpecifically, the airspeed became too low for the AoA reading to be deemed reliable, silencing the stall warning. Definitely a terrible UX.
- danaliv 7y agoAh, thanks for the clarification. From an engineering perspective that makes total sense - and is disastrous from the pilot's perspective!