Thorsten
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After a few more bits of information have come to my attention and a nice discussion:
I don't think there's overly much wrong with the plane. The MCAS is a reasonable system intended to avois a dangerous situation, it can malfunction, then it can be switched off. The fault seems rather with the general circumstances surrounding it all.
* no redundancy in the MCAS AoA sensor - which is probably okay as long as it's halfway transparent to the crew when the system works properly and when not but
* the AoA sensor disagreement light which would alert the crew early on to a possible sensor failure is opt-in by the airline and costs extra, so not all planes have it
* ... which probably could be dealt with if the crew would otherwise be trained how it feels when the system malfunctions and what to do as a response
* but the existence of the system seems to have been played down by Boeing and the company did in fact all to avoid any additional training of the crews
* and to that end, they likely systematically understated the implications of a system failure
So the actual problem seemed to have been that the crews did not figure out in time what the real problem was (due to lack of information and training) and reacted the wrong way - in cases where the problem was recognized correctly by the crew and the system was switched off, no further problems occurred.
Which, well, is still a theme of saving money and compromising safety to do that unfortunately. But it rather seems to be an issue of the general culture and not so much a fault of the MCAS system itself or the engineering.
I don't think there's overly much wrong with the plane. The MCAS is a reasonable system intended to avois a dangerous situation, it can malfunction, then it can be switched off. The fault seems rather with the general circumstances surrounding it all.
* no redundancy in the MCAS AoA sensor - which is probably okay as long as it's halfway transparent to the crew when the system works properly and when not but
* the AoA sensor disagreement light which would alert the crew early on to a possible sensor failure is opt-in by the airline and costs extra, so not all planes have it
* ... which probably could be dealt with if the crew would otherwise be trained how it feels when the system malfunctions and what to do as a response
* but the existence of the system seems to have been played down by Boeing and the company did in fact all to avoid any additional training of the crews
* and to that end, they likely systematically understated the implications of a system failure
So the actual problem seemed to have been that the crews did not figure out in time what the real problem was (due to lack of information and training) and reacted the wrong way - in cases where the problem was recognized correctly by the crew and the system was switched off, no further problems occurred.
Which, well, is still a theme of saving money and compromising safety to do that unfortunately. But it rather seems to be an issue of the general culture and not so much a fault of the MCAS system itself or the engineering.