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Preliminary report into Air India crash released

bbc.co.uk

451–460 of 924 posts

Re: Preliminary report into Air India crash released

#451

Earlier quoted context omitted.

Sometimes people put cleaning liquid in the fridge. Given a long enough span of time, every possible fuck up eventually will happen.

Probably time to design a plane that can't be sent into terrain in seconds by flipping a switch.

And a gun that doesn't let you point it at your face. And a knife that doesn't let you cut yourself. And a car that doesn't let you accelerate into a static object. And...

Re: Preliminary report into Air India crash released

#452
post #396

Earlier quoted context omitted.

> And both pilots deny doing it. > It's difficult to conclude anything other than murder-suicide. You’re trying to prove a negative here. I am not familiar with the 787 operations, but there are a few issues that need to be sorted out first: - altitude when pilots start the after takeoff checklist - if there are any other switches that are operated in tandem in the general vicinity of where the engine cutoff switches…

> Did you ever always push the right buttons every time? A whole world full of 787’s is pushing the right buttons every single day. If we’re talking about accidentally pressing buttons it seems we’d have seen incidents before.

> If we’re talking about accidentally pressing buttons it seems we’d have seen incidents before.

Well, of course I talk about an accidental touch of the wrong buttons.

Flying is very safe, but at the same time, you will never know how many near misses happen daily that don't become accidents.

Re: Preliminary report into Air India crash released

#453

Earlier quoted context omitted.

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

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.

Re: Preliminary report into Air India crash released

#454

> 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 cut off. So the fuel supply was cut off intentionally. The swi…

I wonder if the switches are still in tact after the crash? Can they verify that the switches are mechanically sound? If so, seems highly likely it was intentional.

I'd suspect the wiring leading from the switches to the engine controllers first, especially since it looked like both circuits cut out nearly at the same time.

Re: Preliminary report into Air India crash released

#455

Earlier quoted context omitted.

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

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 dow…

> "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.

Re: Preliminary report into Air India crash released

#456

Earlier quoted context omitted.

It’s always easy in those threads to see who’s familiar with the world of aviation and who’s not. No it’s not comparable to a cop that confuses things in the heat of the moment. Not anywhere close to be relatable. If it was, planes would be crashing down the sky quite often (and it would have been fixed for decades already).

WalterBright is not totally unfamiliar with the aviation world...: > Bright is the son of the United States Air Force pilot Charles D. Bright > Bright graduated from Caltech in 1979 with a Bachelor of Science in Mechanical Engineering and a minor in Aeronautical Engineering > He worked for Boeing for 3 years on the development of the 757 stabilizer trim system

So? The comparison still makes no sense. Those switches cannot be accidentally flipped, and they are in a place where the pilots' hands have no action to take at all during that period. That is very different from mixing up two similar weapons in a similar location.

Location of the switches: https://media.cnn.com/api/v1/images/stellar/prod/c-gettyimag...

Here is a video of a takeoff and climb in a 787: https://youtu.be/TTZozTaWiRo

The pilots have no business with their hands in the area of those switches in that phase of the flight (9:30+ in the video). They don't even have to touch the throttle, and even if they did, that's a long way from where you touch the throttle down to the base where those switches are. Which you can't just flip either.

How is that even remotely similar to that cop's situation?

Re: Preliminary report into Air India crash released

#457
post #448

Earlier quoted context omitted.

> There is no possible way to confuse these two actions. This is obviously an overstatement. Any two regularly performed actions can be confused. Sometimes (when tired or distracted) I've walked into my bathroom intending to shave, but mistakenly brushed my teeth and left. My toothbrush and razor are not similar in function or placement.

That's just your brain associating the bathroom with the act of brushing your teeth, and therefore doing it automatically upon the trigger of entering the bathroom. It bears no resemblance to the accidental activation of a completely different button. The other poster's correction: "it’s like brushing your teeth with razor" is apt. Touching the fuel cutoff switches is not part of any procedure remotely relevant to th…

Now I'm trying to remember if I've ever picked up my razor and accidentally begun tooth brushing motions with it. Probably!

More relevantly, you seem to me to be unduly confident about what this pilot's associative triggers might and might not be.

Re: Preliminary report into Air India crash released

#458

Earlier quoted context omitted.

If I were to apply OPs assertion to your actions it’s like brushing your teeth with razor. I guess that’s what they meant.

Not really, though. They're both (retracting the gear, and cutting off fuel) just toggle switches, as far as your brain's conscious mechanisms go. Doing them both on every flight dulls the part of your brain that cares about how they feel different to perform. (I'm not strongly arguing against the murder scenario, just against the idea that it's impossible for it to be the confusion scenario.)

Neither is a toggle switch and the gear lever is incredibly conspicuous:

https://www.aerosimsolutions.com.au/custom-products/olympus-...

This would be like opening your car door when you meant to activate the turn signal.

Re: Preliminary report into Air India crash released

#459

Earlier quoted context omitted.

If you shut off the engines a couple of dozen meters above ground shouldn’t every alarm be blaring or there should be some sort of additional lever you have to pull way out of the way to enable shutting off the engine that close to the ground.

Consider a case where the engine starts to violently vibrate. This can tear the structure apart. Delaying shutting off the engine can be catastrophic. It's very hard to solve one problem without creating another. At some point, you just gotta trust the pilot.

If you read through the boeing procedures, if an engine fails just after take off you delay cutting throttle or hitting the cutoff until you have positive climb and pass a certain altitude. Specifically because a mistake here would be so incredibly catastrophic. The following number of steps and verbal cross checks for then shutting down the engine are quite daunting. Not something applicable here, but still interesting to learn about

Re: Preliminary report into Air India crash released

#460

Excellent analysis here, those switches are stout, no one is moving them by accident: https://www.youtube.com/watch?v=wA_UZeHZwSw

Except when they are not: From the avherald link: >Service Bulletins by Boeing issued in year 2018 recommending to upgrade the fuel switches to locked versions to prevent inadvertent flip of the switches, as well as the FAA/GE issued Service Bulletin FAA-2021-0273-0013 Attachment 2 relating to loss of control issue (also see above) were NOT implemented by Air India.

You've linked to something regarding an ECU component. Nothing about fuel switches. "This Service Bulletin provides instructions to replace the EEC MN4 bridge ball grid array (BGA) microprocessor"
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