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The landing gear lever is rather prominently featured in the 787 in a panel central to the cockpit layout so that either pilot can easily reach it. For decades and across many manufacturers, the landing gear lever has traditionally featured a knob that deliberately resembles an airplane wheel. It's very hard to mistake it for anything else. It's actuated by simply moving it up or down.

The fuel control switches are behind the throttle stalks above the handles to release the engine fire suppression agents. These switches are markedly smaller and have guards on each side protecting them from accidental manipulation. You need to reach behind and twirl your fingers around a bit to reach them. Actuating these switches requires pulling the knob up sufficiently to clear a stop lock before then rotating down. There are two switches that were activated in sequence and in short order.

The pilot monitoring is responsible for raising the gear in response to the pilot flyings' instruction.

I would find it very difficult to believe this was a muscle memory mistake. At the very least, I would want to more evidence supporting such a proposition.

This idea strikes me as even more unlikely than someone shifting their moving vehicle into reverse while intending to activate the window wipers.



> This idea strikes me as even more unlikely than someone shifting their moving vehicle into reverse while intending to activate the window wipers.

I suspect you've never driven an older vehicle with the shifter on the steering column.


Or a Tesla. I've done this exact thing, although the car just beeped at me and refused to go into reverse, of course.


> I suspect you've never driven an older vehicle with the shifter on the steering column.

Or a new Mercedes ;)


But if he did, would have done hours of retraining in a simulator?


Or even crazier, a manual shift on the steering column. Nothing weirder than pushing down the clutch and then changing the gear with your hand on a knob off to the side of the steering wheel.


Like in a Citroën 2CV?


The pilot wasn’t flying an unfamiliar aircraft.


I think the aircraft being familiar makes it worse: if you're used to going through a certain motion to do a thing, it may be one of things your brain can do without really thinking about it much, which is where the danger comes in.

I've engaged my wipers when meaning to shift gears before, in my truck which has a steering column shifter. After driving the truck for years. I have ADHD and I very often let my brain go on autopilot for things I do every day, and sometimes it just does the wrong thing. It doesn't matter how complicated or "intentional" the task has to be: my brain will memorize it to the point that it can execute it on its own without me consciously thinking about it.

I think it's totally plausible it was a muscle memory thing, if the at-fault pilot's brain works anything like mine.

(Side note: I actually took some flying lessons, including going through all of ground school, and realized that my brain is just not cut out for flying. I am the type of person to "cowboy" things if I feel like they're not worth doing, and flying is an activity where the tiniest missed checklist item can result in death, so I realized I have a statistically high likelihood of crashing due to some boneheaded mistake, and stopped taking lessons.)


There is no temporal nor spatial adjacency to the switches. The switches are equivalent to the ignition on your car, you operate it in the beginning and end of your trip, and there is nothing during the trip that will involve manipulating this switch.


There’s been at least 2 times I’ve turned my ignition switch while driving. (Luckily it was into the “on” position instead of off.)

Everyone in this thread thinking “these actions are temporally and physically distinct and therefore impossible for anyone to confuse” isn’t really thinking about the problem the right way. It’s not that I’m actually confusing two actions. It’s that I’m accidentally allowing my brain to perform one action when I meant to let it perform another action. “Allowing” is an important word here, because it illustrates that my brain is capable of doing this on its own without me thinking about it, and often will do it on its own, if I let it.


If your wipers had the equivalent of a child safety cap it would be hard to do it accidentally, especially twice in a row.


I firmly believe this is not the case. Putting more obstacles between me and the thing I’m trying to do, just trains my brain at rote performance of the task. It’s still “autopilot” as far as my brain is concerned.

This could be anything: starting a car, taking off a medicine cap, typing my password, clicking around cookie warnings. If I have to do it repeatedly, my brain will be able to perform it subconsciously, and I will do it without realizing it.

For fuel cutoff switches, it doesn’t matter that there two of them in a row. If you cut off both of them every single time, and you fly every day, your brain is gonna automate that task.


But the 787 doesn’t have an easily confused layout like that. The landing gear lever and fuel cut off switches are not two stalks on the yoke. Aircraft cockpits are deliberately designed in such a way that important things have differently shaped actuators that feel different from each other. Precisely so that you are not accidentally flipping the wrong switch by accident.


Actually the birth of Human Factors was related to this... Alphonse Chapanis, a psychologist working at the Army Air Force Aero Medical Lab in 1942, investigated the issue and discovered a design flaw. He observed that the controls for the flaps and the landing gear in the B-17 cockpit were nearly identical and located close to each other.


> It's very hard to mistake it for anything else. It's actuated by simply moving it up or down.

On some aircraft types you also have to pull it towards you before moving it to avoid hitting it by mistake.

But I agree it's very unlikely to be a muscle memory mistake.




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