Re:737 Max Explanation by a Software Engineer
by phkahler on Sunday March 17, 2019 @05:28PM
(#19416743)
One would hope MCAS would not do anything if the AoA input was known bad. This looks really bad for the company. I'd be asking for FMEAs and/or FTAs on this, what the conclusions were, and how they intended to mitigate this exact failure - because it's got to be in there.
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Re:737 Max Explanation by a Software Engineer
by zaphar on Sunday March 17, 2019 @09:29PM
(#19418020)
If you've only got 2 sensors and you aren't even reading from one of them then "bad" input is hard to know. You can do nothing if they both disagree but you can't actually know which sensor is bad and which is good without a tie breaker.
Re:737 Max Explanation by a Software Engineer
by ddalex on Monday March 18, 2019 @02:14PM
(#19423534)
You don't need to automatically fix the disagreement. You just need to stop taking nose-down action and inform the human in charge .
Problem is, if you need to inform the human, you also need to train the human, which leads to extra costs.
Re:737 Max Explanation by a Software Engineer
by Gibbon1 on Monday March 18, 2019 @03:54AM
(#19419343)
Who knows but it the chatter makes it sound like the system doesn't have redundant sensors. You have two systems with one sensor each. One system is active and the other is inactive. And no voting logic.