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This is very important, as it shows the ratio of pilots aware of the mitigation is low, and/or the stress of fighting with the the computer makes you forget you
by zaphirplane 8y ago
This is very important, as it shows the ratio of pilots aware of the mitigation is low, and/or the stress of fighting with the the computer makes you forget you training amendments
Edited to add it’s a training amendment
- arcticbull 8y agoIt's a single data point / anecdote. These investigations are incredibly thorough, precise, and authoritative so it makes sense they'd seek to exclude that kind of information until they knew for sure.
- hencq 8y agoI'm not sure that thorough and precise implies they would seek to leave out things. In fact, one would expect the opposite.
- arcticbull 8y agoOne data point may lead you to bad conclusions, like in this case "one third of pilots don't know how to disengage the MCAS" -- the fact is we don't know what ratio. It might be higher, it might be lower, but one data point isn't valuable or thorough. In the preliminary report they mentioned someone else disabled it. In their final, I'm sure we'll get the details.
- tomnm 8y ago> It's a single data point / anecdote. A single data point is still a data point.
- TomMarius 8y agoAn irrelevant one in this case. This report needs to find out the technical/training/... reason, not why the other pilot needed a ride. I'm sure they'd have included it if they wanted to recommend having three pilots on every flight.
- deleted 8y ago[deleted]
- yason 8y agoAnd a very relevant one, in this case: trim runaway with pilots not understanding it's a runaway. The visiting pilot does recognise the situation and restores expected flight dynamics. What went wrong, why did not two pilots realise something that is traditionally a known case and well understood? Because it didn't look like a traditional case.
- cryptonector 8y agoIt also shows that pilot awareness (and therefore training) should have been sufficient. The key deficiency here was Boeing's. The agency not disclosing this detail is a problem too.
- cjbprime 8y agoThat.. sounds like the literal opposite of what it shows, no?
- cryptonector 8y agoI think you misunderstood. Had the pilots been trained, they could have dealt with it -- that the off-duty pilot was able to shows it was possible to respond correctly, while that the others weren't shows the lack of training is a real problem.
- cjbprime 8y agoThanks, I see. I don't think it does much good to notice that a small percentage of pilots can be capable of figuring it out, if they have no other duties at the time. That doesn't tell us that it's reasonable to expect pilots in command under stress to always figure it out. And they have to figure it out 100% of the time to avoid statistically unacceptable crashes. So I don't agree that pilot training is an acceptable answer given what we know so far.
- cryptonector 8y agoYes it does: it shows that there is a procedure that would have worked had the pilots recognized the issue and known about the procedure. The pilots were stressed in part because they didn't know -- they had plenty of time to recognize the issue and take action had they known, but they didn't, so no amount of time would have helped them. We don't know if one more thing to know about would too much, but I rather doubt that.
- averros 8y agoActual instrument-rated pilot here. What people (including pilots) do under stress is resort to simple actions drilled in by training. That's why emergency procedure training is a major part of pilot training curriculum. What goes away first under stress is capability for complex reasoning, which is what one would need to figure out what the heck is going on and take appropriate action. In this case an a/c doing uncommanded dive can be a result of three things: elevator controls malfuncion (unlikely in modern jets, the mechanisms for transmitting control forces from the yoke to the elevator are multiply redundant and well-understood to be critical), structural breakdown (empennage falling off would do that), or run-away elevator or stabilizer trim. In most a/c the runaway trim can be only caused by malfunctioning auto-pilot (that's why APs have multiple redundant ways to disable them), so the pilots faced this situation react by trying to disable AP in all available ways and then immediately jumping to conclusion that there's something catastrophically wrong with elevator system or even airframe integrity. The thought that there could be yet another system which can do major trim adjustment doesn't even enter their consciousness. Training (and/or being in a position where there's no immediate stress of wrangling misbehaving a/c) would help to get to the correct solution (disabling trim motor by pulling the circuit breaker). That said, flying an a/c seriously out of trim is hard, and can cause an accident on its own (the fine pitch control is gone, and you can even be so far out of trim that you cannot do landing flare no matter how hard you pull up, which in heavy jets would result in structural breakdown when the plane slams into runway).
- StavrosK 8y agoMy question is why doesn't the "omg something is seriously fucked up give me manual control NOW" button disable the MCAS as well? That seems like a UX failure.