The report says the black box reports the fuel cutoff switches being activated. That doesn't necessarily mean that either of the two pilots activated them, it just means that the fly-by-wire system reacted to a fuel cutoff event.
"The aircraft achieved the maximum recorded airspeed of 180 Knots IAS at about 08:08:42 UTC and immediately thereafter, the Engine 1 and Engine 2 fuel cutoff switches transitioned from RUN to CUTOFF position one after another with a time gap of 01 sec. The Engine N1 and N2 began to decrease from their take-off values as the fuel supply to the engines was cutoff.
In the cockpit voice recording, one of the pilots is heard asking the other why did he cutoff.
> That doesn't necessarily mean that either of the two pilots activated them
It does:
1. Those switches have physical interlocks and cannot be manipulated by any computer system.
2. The flight data recorder is measuring the position of the switches; they aren't inferring the position from some system state. There's a "position of this switch" channel.
The switches were physically moved in the cockpit, that's basically ground truth. The question now is who and why.
What is the path of the wires from the switch onward? Do they go into a digital input of the flight computer, or do they directly feed the fuel control valves?
The 787 entered service with an improved fly-by-wire flight control system. Rather than mechanical processes, the systems convert flight deck crew inputs into electrical signals. Still, there were additional advancements with the type."
No, lacking other evidence (e.g. CVR recording) it doesn't mean they have been moved. The wiring in between the switches and the engine+FDR could've also developed an intermittent fault.
The fact that your car's engine stops doesn't mean you turned the ignition switch off. Anyone who has had to troubleshoot a car with intermitent electrical faults knows that.
> This was not suicide, or murder-suicide; it was one of the most horrific mass murders in history, in which the guy that did it happened to lose his life in the process.
Why wouldn’t this qualify as a murder-suicide, assuming your theory is correct?
I guess I let my emotions get in the way. But nobody seems to be saying that we’ve witnessed one of the worst acts of mass murder in history. Most of the notorious serial killers don’t come close to killing 300 people.
It feels qualitatively different than someone pointing a gun at someone else and then themselves, which is usually what pops to mind when you hear “murder-suicide”.
> This was not suicide, or murder-suicide; it was one of the most horrific mass murders in history, in which the guy that did it happened to lose his life in the process.
Even taking intent for granted, to deny suicide in a case like this would be to suppose that the person responsible expected to survive while everyone else died. What could possibly support that conclusion?
He appears to have meant something like “this isn’t just common murder-suicide: it is a particularly heinous version of murder-suicide that I wish there were a stronger word for” but phrased it confusingly.
As someone with no qualifications on this beyond occasionally playing some flight simulators, I can't think of a reason you would ever intentionally move the switches in flight (barring an emergency like a leak or fire or something) and unintentionally doing so seems extremely unlikely since generally "switches meant to be operated on the ground" are located well out of the way of "switches meant to be operated in flight". Though I believe Boeing does have them by the thrust levers, every type of fuel control switch I've seen has some sort of guard or mechanism that makes it effectively impossible to move the switch by simply bumping it.
So I can't imagine how it could have been done accidentally.
I am, and I’m willing to stake my reputation on it. If I’m wrong, I’ll hang up my hat and never cover live news again.
Pilots are drilled from day one that the fuel switches are sacred. After a few accidents where one engine failed and the pilot accidentally turned off the remaining functional engine, the training was overhauled so that it would be impossible for it to be an easy action done by mistake. One pilot is required to ask the other for confirmation before toggling the switch, I believe. It wouldn’t be something you’d do from muscle memory.
> If I’m wrong, I’ll hang up my hat and never cover live news again.
It easy to say that when you know there's likely no way to prove or disprove whether it as an accident or not. Unless a pilot left a note stating his future intentions, there's no way to determine their state of mind.
The switches require that you pull them out, move them to the end position and then push them back down, and it was two switches. It could have still took off on one engine. This is essentially the turn off plane switch. It would seem to almost impossible that it would be an accident.
Not possible it's an "I bumped it" type of accident, maybe.
It's quite possible it's a "performed the wrong muscle memory at the worst possible moment" type of accident. This is unlikely, but anyone who thinks such a mistake is impossible doesn't know anything about human factors.
Unlikely just means "low probability." There are thousands of flights per day, so it's only a matter of time.
You mention "brain fart". There is certainly a long history of pilots selecting the wrong lever, or wrong switch. So, it is possible the pilot who denied switching the fuel off thought he had switched something else.
My understanding is that after several incidents of pilots shutting off the wrong engine, the training was overhauled so that from day one they treat fuel switches as sacred. I heard that it’s required to ask for confirmation before toggling the switch, just to be absolutely certain. It’s not really something that can be done by muscle memory during flight, and especially not during takeoff.
If he was trying to do something else, he would have called it out. E.g. an audible “gear up.”
Also, it took 10 and 14 seconds to switch them back on. If it was an accidental switch, you would think it would have been quicker to switch them back.
I have a couple of those type of switches, though smaller, in my parts bin. They were from some piece of surplus equipment that got junked. Where I've seen them used is in a crowded control panel where they might just get bumped. The two red plastic levers to the left are another type of safety switch: The lever is spring loaded, and covers the handle of a toggle switch.
In my view it would be quite hard to move them by accident, and probably not possible to move at once.
It would be interesting to know if the plane has any other switches of the same type, that are routinely activated.
Sadly not. It’s a physical switch with no capability of a remote toggle. The flight data recorder clearly shows one was toggled off within a second of the other, which rules out almost every non-intentional scenario.
Is this a switch that has a dedicated connection to the corresponding cutoff valve? Or does it go through some common digital bus that passes commands? If so, how well is this bus protected?
The report says the co-pilot was flying.
The report says the black box reports the fuel cutoff switches being activated. That doesn't necessarily mean that either of the two pilots activated them, it just means that the fly-by-wire system reacted to a fuel cutoff event.
"The aircraft achieved the maximum recorded airspeed of 180 Knots IAS at about 08:08:42 UTC and immediately thereafter, the Engine 1 and Engine 2 fuel cutoff switches transitioned from RUN to CUTOFF position one after another with a time gap of 01 sec. The Engine N1 and N2 began to decrease from their take-off values as the fuel supply to the engines was cutoff.
In the cockpit voice recording, one of the pilots is heard asking the other why did he cutoff.
The other pilot responded that he did not do so."
> That doesn't necessarily mean that either of the two pilots activated them
It does:
1. Those switches have physical interlocks and cannot be manipulated by any computer system.
2. The flight data recorder is measuring the position of the switches; they aren't inferring the position from some system state. There's a "position of this switch" channel.
The switches were physically moved in the cockpit, that's basically ground truth. The question now is who and why.
What is the path of the wires from the switch onward? Do they go into a digital input of the flight computer, or do they directly feed the fuel control valves?
https://simpleflying.com/boeing-787-technical-features-guide...
" Advanced electric controls
The 787 entered service with an improved fly-by-wire flight control system. Rather than mechanical processes, the systems convert flight deck crew inputs into electrical signals. Still, there were additional advancements with the type."
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No, lacking other evidence (e.g. CVR recording) it doesn't mean they have been moved. The wiring in between the switches and the engine+FDR could've also developed an intermittent fault.
The fact that your car's engine stops doesn't mean you turned the ignition switch off. Anyone who has had to troubleshoot a car with intermitent electrical faults knows that.
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I don’t understand this part of your post:
> This was not suicide, or murder-suicide; it was one of the most horrific mass murders in history, in which the guy that did it happened to lose his life in the process.
Why wouldn’t this qualify as a murder-suicide, assuming your theory is correct?
I guess I let my emotions get in the way. But nobody seems to be saying that we’ve witnessed one of the worst acts of mass murder in history. Most of the notorious serial killers don’t come close to killing 300 people.
It feels qualitatively different than someone pointing a gun at someone else and then themselves, which is usually what pops to mind when you hear “murder-suicide”.
You’re correct though, it qualifies.
> This was not suicide, or murder-suicide; it was one of the most horrific mass murders in history, in which the guy that did it happened to lose his life in the process.
Even taking intent for granted, to deny suicide in a case like this would be to suppose that the person responsible expected to survive while everyone else died. What could possibly support that conclusion?
He appears to have meant something like “this isn’t just common murder-suicide: it is a particularly heinous version of murder-suicide that I wish there were a stronger word for” but phrased it confusingly.
Maybe that one guy who survived did it? Are there fuel cutoff switches near seat 11A?
As someone with no qualifications on this beyond occasionally playing some flight simulators, I can't think of a reason you would ever intentionally move the switches in flight (barring an emergency like a leak or fire or something) and unintentionally doing so seems extremely unlikely since generally "switches meant to be operated on the ground" are located well out of the way of "switches meant to be operated in flight". Though I believe Boeing does have them by the thrust levers, every type of fuel control switch I've seen has some sort of guard or mechanism that makes it effectively impossible to move the switch by simply bumping it.
So I can't imagine how it could have been done accidentally.
> it was one of the most horrific mass murder in history
This implies intent.
> One pilot asked “why did you turn them off?” and the other said “I didn’t.”
To me this reads like an unintentional error with colossol implications.
Are you suggesting there was malicious intent and then a delibrately crafted denial by the perpetrator?
I am, and I’m willing to stake my reputation on it. If I’m wrong, I’ll hang up my hat and never cover live news again.
Pilots are drilled from day one that the fuel switches are sacred. After a few accidents where one engine failed and the pilot accidentally turned off the remaining functional engine, the training was overhauled so that it would be impossible for it to be an easy action done by mistake. One pilot is required to ask the other for confirmation before toggling the switch, I believe. It wouldn’t be something you’d do from muscle memory.
> If I’m wrong, I’ll hang up my hat and never cover live news again.
It easy to say that when you know there's likely no way to prove or disprove whether it as an accident or not. Unless a pilot left a note stating his future intentions, there's no way to determine their state of mind.
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The switches require that you pull them out, move them to the end position and then push them back down, and it was two switches. It could have still took off on one engine. This is essentially the turn off plane switch. It would seem to almost impossible that it would be an accident.
Not possible it's an "I bumped it" type of accident, maybe.
It's quite possible it's a "performed the wrong muscle memory at the worst possible moment" type of accident. This is unlikely, but anyone who thinks such a mistake is impossible doesn't know anything about human factors.
Unlikely just means "low probability." There are thousands of flights per day, so it's only a matter of time.
I mean lots of people in prison say they are innocent
These are not facts. These are mostly speculation.
You mention "brain fart". There is certainly a long history of pilots selecting the wrong lever, or wrong switch. So, it is possible the pilot who denied switching the fuel off thought he had switched something else.
My understanding is that after several incidents of pilots shutting off the wrong engine, the training was overhauled so that from day one they treat fuel switches as sacred. I heard that it’s required to ask for confirmation before toggling the switch, just to be absolutely certain. It’s not really something that can be done by muscle memory during flight, and especially not during takeoff.
If he was trying to do something else, he would have called it out. E.g. an audible “gear up.”
Also, it took 10 and 14 seconds to switch them back on. If it was an accidental switch, you would think it would have been quicker to switch them back.
If you look at the photo https://theaircurrent.com/aviation-safety/ai171-investigatio... it would be pretty hard to get them by mistake.
I have a couple of those type of switches, though smaller, in my parts bin. They were from some piece of surplus equipment that got junked. Where I've seen them used is in a crowded control panel where they might just get bumped. The two red plastic levers to the left are another type of safety switch: The lever is spring loaded, and covers the handle of a toggle switch.
In my view it would be quite hard to move them by accident, and probably not possible to move at once.
It would be interesting to know if the plane has any other switches of the same type, that are routinely activated.
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Is there a possibility that they got hacked and remotely toggled ?
Sadly not. It’s a physical switch with no capability of a remote toggle. The flight data recorder clearly shows one was toggled off within a second of the other, which rules out almost every non-intentional scenario.
Happily not. If this were possible, it would open up a whole universe of problems.
Ok but you used 'sadly' incorrectly I presume.
Is this a switch that has a dedicated connection to the corresponding cutoff valve? Or does it go through some common digital bus that passes commands? If so, how well is this bus protected?
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What if he mistook the switch for a different switch?
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