[belter]

The evidence points to inadvertent fuel cutoff switch movement rather than pilot error, or intentional pilot action. Most likely cause being locking mechanism failure combined with takeoff acceleration forces.

Investigation and preliminary report is not showing critical evidence that would help clarify. Like the full transcript of pilot conversations that is clearly already available, and if these switches had any maintenance in the last year.

The fact that both pilots denied moving the switches, combined with the extremely short timeline, makes mechanical/electronic failure the most probable cause.

Note the Critical Sequence:

08:08:39 UTC: Aircraft lifts off (air/ground sensors transition)

08:08:42 UTC: Maximum airspeed of 180 knots reached

08:08:42 UTC: IMMEDIATELY after max speed, both fuel cutoff switches transition from RUN to CUTOFF (1 second apart)

08:08:47 UTC: Both engines below minimum idle, RAT deploys

08:08:52 UTC: Engine 1 switch returns to RUN

08:08:56 UTC: Engine 2 switch returns to RUN

So only 3 seconds between liftoff and fuel cutoff. Extremely short window for deliberate pilot action...

[pertymcpert]

That doesn't make sense. If a pilot wanted to deliberately cut off the engine there's no reason they couldn't do at that time. The time difference between the switches being one second shows it was more likely to be deliberate, not less. An accidental hit would result in both happening at the same time, not with a time delay.

[belter]

The two switches changed in sequence, but within the same second and at max speed. Dont think a human can have such a timing. If you look at the timing it looks more and more like electronical or software triggers.

Another possibility is a foreign object like a personal item sliding back during acceleration.

I looked at both pilots background, and unless a story of medical depression on the part of the captain emerges, I dont see the pilot suicide as plausible.

[pertymcpert]

FAA just announced they examined the switched and found no mechanical issues. The switches are not software controlled.

Seems like the evidence is starting to become fairly one sided…

[belter]

I agree the evidence points to the Captain, but the report did not provide the full text of the pilots interaction. The timestamps shows they were cut, one after the other, but within the same second as max vspeed. Doubt humans can have that precision.

>> The switches are not software controlled.

That is what unethical people, like Captain Steeeve - Who changed his "accident clear cause" story four times since the accident - keep saying.

But on the 787, fuel switches are part of the electronic cockpit interface and toggling one sends a command via AIMS to the Engine Interface Unit, then over AFDX to the FADEC. The FADEC actuates the spar and engine fuel shutoff valves who are both electrically controlled with no mechanical linkage.

The switch itself doesn’t cut fuel, it initiates a command interpreted and executed by software. Additionally, software logic can override or block the command based on conditions like fire, overspeed, or sensor faults so its software-controlled end-to-end.

A faulty sensor could trigger even if so far evidence points to the Captain.

"Understanding the Boeing 787 Fuel Control Switch: Function, Operation, and Safety Mechanisms" - https://aeropeep.com/boeing-787-fuel-control-switch-explaine...

"How do the fuel cutoff switches on the Boeing 787 work?" - https://aviation.stackexchange.com/questions/110938/how-do-t...

"Full Authority Digital Engine Control (FADEC)" - https://skybrary.aero/articles/full-authority-digital-engine...

"Full authority digital engine controls have no form of manual override available, placing full authority over the operating parameters of the engine in the hands of the computer.

- If a total FADEC failure occurs, the engine fails.

- Upon total FADEC failure, pilots have no manual controls for engine restart, throttle, or other functions."