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Preliminary report into Air India crash released

bbc.co.uk

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Re: Preliminary report into Air India crash released

#331

Post by epolanski »

burnt-resistor wrote: post #320
epolanski wrote: post #289

Earlier quoted context omitted.

The car equivalent is being on a highway and "mistakenly" pulling the hand brakes, except that there are 2 hand brakes and you need to first unlock both of them. That's very hard to do by panic and mistake, if not impossible by design.

Bad analogy because pilots are trained and rehearse and practice memory items until they are instinctual. > impossible by design. Deflecting that the human is the weakest part of the system. One or other may have panicked and made a mistake, made a mistake unintentionally, went crazy and doomed the flight, or intentionally doomed the flight for some socioeconomic reasons. These are speculative possibilities that we d…

Forget my words then and take those from aviation experts.

The fact that a pilot would cut off fuel from both engines, in sequence while taking off is virtually impossible to happen unless deliberate.

Hence the hand brake comparison, it does not come natural to use it while driving.

Re: Preliminary report into Air India crash released

#332

Post by moralestapia »

whatevaa wrote: post #329
moralestapia wrote: post #318

Earlier quoted context omitted.

Sure, and aliens could also be involved. However, the only relevant evidence that exists suggests they had enough rest. You don't build verdicts on suppositions, you build them on proven facts. This does not guarantee you will reach the truth, but it's miles better than admitting every baseless hypothesis that comes up.

This is preliminary report. They will look deeper into this. Don't sentence people on unfinished investigations. This is why most trials are not public, because of people like you.

I'm glad you read my other comment [1].

1: https://news.ycombinator.com/item?id=44539508

Re: Preliminary report into Air India crash released

#333

Post by vishnugupta »

cjbprime wrote: post #156
russdill wrote: post #124

Earlier quoted context omitted.

There is no possible way to confuse these two actions. There's a reason a wheel is attached to the gear lever.

> 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.

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.

Re: Preliminary report into Air India crash released

#334

Post by anonzzzies »

resist_futility wrote: post #220
deadbabe wrote: post #216

Earlier quoted context omitted.

there's literally two other similar switches right next to those?

The switches on the lower panel that are switched, are the fuel cutoffs

But they don't look protected or hard to switch?

Re: Preliminary report into Air India crash released

#335

Post by ExoticPearTree »

heisenbit wrote: post #38
joezydeco wrote: post #29

Earlier quoted context omitted.

Report says the switches went to cutoff one second apart from each other. Can a human do the physical operation on two switches that quickly?

The timing is really curious. 08:08:35 Vr 08:08:39 Liftoff 08:08:42 Engine 1 cut-off 08:08:42 Engine 2 cut-off 08:08:47 minimum idel speed reached ?? One pilot to other: why cut-off. Other: Did not do it 08:08:52 Engine 1 run 08:08:52 Engine 2 run 1 second to switch them both off and then 4 seconds to switch them both on. No one admitted to switch them off. They are probably going with fine comb over the audio and al…

> Looks like the engines react very quickly to cut-off so it is not clear whether the question about the cut-off is prompted by a glance to the switches or the feel of the airplane.

The workload is pretty high during the takeoff phase. The engines react right away when fuel flow is stopped. The engine displays can have some lag before data is updated.

Relighting an engine at low speed is not feasible - most need 230-250kts IAS before attempting the operation. Maybe you could do it if the APU was still running and could provide compressed air, but it takes about 20-30 seconds to start up amd then probably 5-10 more to spool up to full thrust. I am speculating here a bit, but the pilot did not have enough time to save the plane even if he did everyting right and as fast as humanly possible.

All this aside is overshadowed by the limited amount of time the pilot flying (I would assume the captain in this case since there was only one ATPL pilot in the cockpit) had to troubleshoot the issue of a dual engine failure - as this is what would have felt to him - during takeoff.

Re: Preliminary report into Air India crash released

#336

Post by efitz »

It’s interesting to see how many people are bending over backwards here to avoid coming to the obvious conclusion. If this was pilot suicide, it’s a terrible thing. If it was somehow an error (which seems very unlikely) or two defective controls (which seems even more unlikely), then it remains a tragedy. But I don’t need to do mental gymnastics to come up with implausible hypotheticals.

This comment stream on HN is not a jury. We don’t have to refrain from making judgments right now about what happened. There is nothing wrong with rational people reaching a preliminary conclusion based on available evidence.

Rational people should also remain open to revising their judgments/conclusions if new information becomes available.

And we shouldn’t demand any specific consequences for anyone absent a trial.

Re: Preliminary report into Air India crash released

#338

Post by card_zero »

coolspot wrote: post #324
card_zero wrote: post #317

Earlier quoted context omitted.

Cutting the engines within seconds of leaving the ground doesn't fit suicide very well. I'd expect something more like flying into the side of a mountain or heading really far out into the Indian ocean until you vanish from radar and cause a big mystery. For instance, you might deliberately kill yourself by driving your car really fast into something solid, but you probably wouldn't try to do that while backing out o…

I think it is opposite. Flying into a mountain & etc would require one pilot to somehow incapacitate another pilot. Cutting fuel off, if done on takeoff, is not recoverable (engines can’t relight and spin up quickly enough).

OK, that makes a kind of sense, altitude would spoil the plan, if a suicidal pilot's only plan was to cut the engines.

Re: Preliminary report into Air India crash released

#339

Post by ExoticPearTree »

Spooky23 wrote: post #299
chupchap wrote: post #12

Earlier quoted context omitted.

Or a mechanical failure

Serious question: why is it so difficult to fathom that a deranged pilot could decide to commit suicide by plane?

To answer your question: because it is a very rare occurence.

Re: Preliminary report into Air India crash released

#340

Post by yallpendantools »

ls-a wrote: post #148
decimalenough wrote: post #11

> 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…

So you're telling me that those switches don't have a voice that says "fuel cutoff switches transitioned" like in the movies? That's bad design

I know this thread runs the gamut of armchair experts, pretend experts, and actual experts and there's no telling who is which but I really want to know why the downvotes and why this is not a good idea.

The idea is to notify for crucial settings, replace vocal confirmation (probably) already in the SOP anyway, reducing mistakes in bad faith or otherwise.

Don't some planes already have an automated announcement for seatbelts on?

Only reason I can think of why it's not there yet is the cost (whether $$$ or design opportunity) of cramming that in the already-cramped cockpit.

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