Comment by noqc
1 day ago
The murder suicide angle isn't particularly worthy of assumption yet. Have you ever put your phone in the fridge?
Pilots deactivate the fuel cutoff at the end of the final taxi to the gate. This makes flipping these switches a practiced maneuver, capable of being performed without conscious thought, regardless of whether they came with safety locks installed.
Brain farts are a real phenomenon, and an accidental fuel cutoff most closely resembles the transcript from within the cockpit.
The report is actually a little cagey about whether the locks were properly installed on these switches. Said locks are supposedly optional. Until I receive a more direct confirmation that the switches were installed with their full safety features, I will assume that it is more likely for the plane to have had improperly installed switches than not, given that the shutoff was the reason for the crash, and if they turn out to have been installed, I will assume that simple pilot error is responsible until a motive for murder is found. The pilots lives are under quite a lot of scrutiny, and I do not believe that a motive for murder is likely to be found.
> The report is actually a little cagey about whether the locks were properly installed on these switches. Said locks are supposedly optional.
The locks/gates on the switches are definitely NOT optional. There was an SAIB about some switches that may have been installed improperly. It didn't result in an AD, which likely means the extent was limited or potentially even nil.
The switches were moved to cutoff with a one second delay between the first and second switch. That's pretty suggestive of deliberate movement. I've flown a Max9 simulator, which has the same switches. Moving one of them by accident would be impossible, let alone two of them.
I agree with not jumping to conclusions about the pilots and possible motives or circumstances, but I will bet a lot of money that the switches were just fine.
The CVR will likely have audio of the switch movement to confirm as well.
The switch must be lifted and turned. The optional posts block you from inadvertently knocking the switch (that you must pull up and turn).
I second that it’s not an accidental motion, you must actively manipulate the switch. But just like your turn signal in your car, it is muscle memory when you use it. I just wonder what action the pilot mistook the fuel cutoff for. Looking around the cockpit shows just how unique those switches are and not something you mistake with another common activity.
Pretty sad day if this was an intentional action
> one second delay
did the report say a one second delay or that the two switches were turned off at consecutive seconds? The latter is what I remembered, but I'll check again.
The report can be found here: https://aaib.gov.in/What's%20New%20Assets/Preliminary%20Repo...
> did the report say a one second delay or that the two switches were turned off at consecutive seconds?
The report states, on page 14: 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.
"with a time gap of 01 sec" seems fairly clear. The final report will have more granularity, but I don't think that's very ambiguous.
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If you were correct, the only situation it would happen in is when the pilot flying asks for X to happen, and the pilot monitoring instead does Y. Pilots don’t just randomly reach over and screw with the controls. Everything is called out, and as far as I know there were no callouts here (e.g. “gear up”).
This is a bit like someone parking their car, pulling the handbrake, turning off the car and putting their keys in their pocket, then arguing that it’s a practiced maneuver because it happens at the end of every car ride.
Look at a 787 cockpit. There are no other switches like that anywhere in the vicinity of those cutoff switches.
This is like pulling the handbrake on the highway when you’re trying to use your high beams
Turning the fuel off seems roughly equivalent to turning the ignition off when you've parked your car. It's really something rather unlikely to do as a brain fart during takeoff.
Most commercial aircraft have quite a few more buttons, knobs, levers, dials, etc than a car.
They do make an effort to make it hard to do safety critical stuff by accident though in cars, small planes and jets. Like in a car it's easy to mix indicators and windscreen wipers which are on various stalks but turning off the engine and locking the steering is very different action, on traditional cars turning the key and taking it out. Similarly here the fuel cut offs are obvious levers that have to be pulled out before they can be moved.
Commercial aircraft pilots are also much better trained than car drivers.
You have to lift and turn these knobs. Hard pressed to think of other knobs like this one. Especially that there are none like it anywhere near those cutoff switches. It seems intentionally designed this way
Putting your phone in the fridge seems like a pretty crazy thing to do, but we do it sometimes. Plane crashes are very rare.
I don't fly a lot of planes, but I do know what muscle memory is like, and sometimes it misfires. Misfires are rare, but then, so are plane crashes.
The emergency fuel cutoff should not be a practiced maneuver.
you make some good points but i thought your example was funny. No, i have never left my phone in the fridge. And i’m in my 30s, so not that young.
I HAVE sometimes “lost” my phone in my own backpack though (lol).
Here’s my take as a non-pilot. Takeoff is a sequence of checklists and procedures that are repeated. Often. If it’s muscle memory, a brain fart seems very unlikely… that’s why i’m skeptical of your theory.
A better analogy would be “have you ever forgotten to put on shoes before leaving your house?” And no, i have not, even during emergencies or when i’m very tired (like when i had to rush my wife to the ER). Why? because that’s something i do daily, and is part of my checklist when departing my house.
Or “have you ever forgotten how to get to work?” that also is extremely unlikely, because one typically follows the same exact steps and route daily. And i don’t randomly turn off my engine while driving, even if i’m multitasking or im forced to take a slightly different route due to a detour.
To be clear, i’m not saying it’s physically impossible. I just find it inconceivable.
These switches are locked into place with a spring loaded detent switch. It's impossible to accidentally switch these off.
You say muscle memory. No muscle memory is involved in fuel cut off for both engines seconds after take off. There is no procedure remotely similar.
Brain farts are literally not a real phenomenon.