And fuel cutoff is _two_ down motions? That's the death knell for this theory, imo.

I don't think the theory is that the muscle memory sequences resemble each other.

Instead, it's that because muscle memory allows you to do things without thinking about it, you can get mixed up about which action you meant to perform and go through the whole process without realizing it.

Is actuating the fuel cutoff switches something that is done routinely in these aircraft, to the extent it could reasonably become muscle memory?

ETA: downthread it is mentioned that these switches are used on the ground to cut the engines

Seems akin to something like a parking brake. Something you only use at a stop, or rarely during an emergency.

They're pilots, they do hundreds of stops each year. In case of domestic pilots, even thousands. And with years of experience, switching off fuel control switches is basically muscle memory at this time now.

Was amused to see they have one of those too, with "parking brake" written on it.

Would anyone be surprised if an accomplished concert pianist played C Bb Bb instead of C E in a piece they had played thousands of times correctly?

The only difference here is that the consequences are death instead of mere head shaking.

Murder needs more proof than just performing the wrong action. Until then we should apply Hanlon's Razor.

That's a ridiculous analogy. The pilots aren't sitting in front of a uniform set of keys that they need to press in a specific order with a specific timing.

The mistake equivalent to what the pilot supposedly did would be if the pianist accidentally stuck a finger up his nose instead of playing the notes or something.

Quite, but the point is that even after doing something correctly a thousand times, someone can make a mistake that seems unbelievable.

The cutoff switches are operated every flight so the muscle memory is there, ready to be triggered at the wrong time.

All we know is that something went wrong in the pilot's head in at least a single moment that caused him to perform a ground action during takeoff.

Depressive murder-suicide is one possible explanation. Altered mental state is another: insomnia, illness, drugs/medications could all explain an extreme brain fart. Perhaps he just had food poisoning? It's India after all.

I keep reading "muscle memory" but the theory that one pilot shut down the engines instead of performing another action has nothing to do with muscle memory.

Muscle memory allows you to perform both actions effectively but doesn't make you confuse them. Especially when the corresponding sequence of callouts and actions is practiced and repeated over and over.

All of us have muscle memory for activating the left blinker in our car and pulling the handbrake, but has anyone pulled the handbrake when they wanted to signal left?

Another comment has the right analogy: has anyone here accidentally unplugged their mouse when they meant to hit caps lock?

i have several passwords i type all the time. sometimes i get them confused and type the wrong one to the wrong prompt. i type them by muscle memory, but i also think about them while typing and i think thoughts like "time to reach up and to the left on the keyboard for this password". I couldn't tell you the letter i'm trying to type, i just know to do that.

not all my passwords are up and to the left, some are down and to the right, but when i type the wrong one into the wrong place, i type it accurately, i'm just not supposed to be typing it.

"time to do that thing i've practiced, reach to the left". shuts two engines off by muscle memory.

My editor is MicroEmacs, which I've been using since the 1980s. I no longer remember what the commands are, but my fingers do.

I remember once writing a cheat sheet for the commands by looking at what my fingers were doing.

> "time to do that thing i've practiced, reach to the left". shuts two engines off by muscle memory.

If that were true, pilots would perform arbitrary motions all the time. Same with car drivers.

Typing something on a keyboard, especially when it's always in the same context, is always essentially the same physical action. The context of a password prompt is the same, the letters on the keyboard feel the same and are right next to each other.

Not comparable to pressing two very different buttons placed far apart, in a context when you'd never ever reach for them.

Sometimes I drive all the way home without being aware of what I did in between.

One time I almost drove to work instead of the shopping mall, because driving to work was basically subconscious. But my car doesn’t have safety features designed to stop me doing that. And I never did it twice in a row.

that makes it less likely, not impossible, we're trying to match against the data we have. I think distracted muscle memory is more likely than suicide and sounding innocent while lying about it