Oh lord… 
I’ve never had to fly for one of those, thankfully.
That said, we pilots sometimes can put enough pressure on ourselves, if we’re not careful…
Not a chance. Those are the stab cutout switches. They are never touched except in the sim. They are the same switches that LionAir and Ethiopian “failed” to utilize in the Max disasters.
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Ok, so in no way related to a possible re-emerging STAB POS XCDR error?
I’m just trying to find a reason for one of the pilots to be fiddling with switches in that area…
I don’t think so. That flight deck is so sensible that mistakes of that sort are as unlikely as colliding with a Faery. A runaway trim is a one in a billion event that is probably handled by the FBW system. The switches are well-placed and capped. I just don’t see much chance of mistaking them. Nor would the slow rate of trim justify reaching for them without going through the EICAS actions as a crew. Activating switches willy-nilly just isn’t done.
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Under the influence? A very bad hangover? Or as Mentour Pilot said, “the brain fart of the century?” All of these are extremely long shots, IMHO.
According to the report they had a breathalyzer test.
What about wiring? There could have been maintenance in that region just an hour before. How does Aircraft wiring even work? Are these Bus systems?
I think the FDR was able to record the switches being physically moved.
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No they would have seen that in the QAR/WQAR and CVR/FDR boxes. These switches have a few dozen wires coming out of them that relate to all the microswitch positions inside. The systems that determine a switch position on the flightdeck are very solid in that regard. The 787 loves documenting everything so no if this would have been a technical issue it would have been clear already and we probably would have seen widespread action on the 78 fleets worldwide.
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I agree, that ‘s why I keep thinking of options.
But I keep coming back to a wilful act…
Switches have insulated contacts so it’s pretty much impossible for a loose metal object to short them out. Something could’ve cut the wires, but that would be a simultaneous event and the switches wouldn’t work afterwards.
I haven’t heard of physical registration of switch position, like @smokinhole mentions, but modern enhanced flight recorders of today register a lot, so maybe it’s a thing now? But the fact that the signal is registered in cutoff, a crewmember asking why, and then they are set to run again, tells us that the switches were physically set to cutoff. Who dunnit? We’ll see.
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It has been a thing since the 90’s. the 777 for example has all the switch positions register in dedicated boxes that then translate the signal to something that can go on the AIMS bus and be transmitted to their designed receivers. The 787 is way fancier with what it can see when it comes to switches and controls.
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Thank you for the insights, Snark. Very interesting, love the details.
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Cool. How does this work? A sensor in the switch, that register the position, separate from the signal?
Some do yes, not sure all of them function like that though.
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Most of the big switches like that have multiple contacts, as mentioned before. Once I watched maintenance replace a battery switch that had worn contacts and it was mind-boggling how many wires were soldered onto the back of it! Never thought about it, but I don’t doubt at all that one of those could feed into the FDR to monitor switch position.
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An ’Aviation Expert’ called Mary Schiavo claims this has happened before…
I don’t know who she is, nor her credentials. I do know, though, that over here, anybody who wants to go on the air and claims to be an expert, will get that title. So I’m careful when it comes to media proclaimed experts. This is no slight on Mrs. Schiavo, I just don’t know her.
Soo… a 787 fuel cutoff switch can move all by itself? It has that capability?
If so, follow-up question: And which situation in ground mode would call for that?
Edit: apparently in the Japan incident the software cut the fuel. I don‘t think it can move a switch. Since in India it was recorded that both switches moved, this is unlikely to be the same cause.
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I doubt it.
Seems like the ANA incident was a software issue.
I guess that could be the case in the Air India accident as well, but why would one pilot ask the other why he set the switches to cutoff?
If the engines quit because the software overrides the switch positions, would a pilot ask why the switches were set to cutoff…? Doesn’t make sense.
Unless there’s something lost in translation. We haven’t heard the CVR nor read a transcript. Maybe the pilot is saying something else…?
Edit.
Reply to the edit 
The preliminary report does indeed state that the switches transitioned from run to cutoff.
I am curious as to how this is registered though. We will probably see an explanation in the full report.
I would give Mrs. Schiavo credit if the report stated something like the fuel valve transitioned to cutoff…
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Mary Schiavo is the worst of the worst. Highly underinformed. Highly media-whoreish. Nearly always wrong.
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Ah… Can’t say I’m surprised.
I am not saying that she is wrong in her assertions about ANA or their TCMAS incident (1st I’ve heard of it). But her history has always been to make the most outrageous claims so that CNN calls her first whenever aviation chips in to help them sell pharmaceuticals.
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