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Preliminary report into Air India crash released

bbc.co.uk

291–300 of 924 posts

Re: Preliminary report into Air India crash released

#291

Even if the plane had no power, why couldn't they have glided it down safely?

Impossible. Low and slow conditions with insufficient energy to 180 return or crash land safely straight ahead in any form. The power loss happened at the most critical phase of flight. Plus, they were on the heavy side.

Re: Preliminary report into Air India crash released

#292
post #22

Earlier quoted context omitted.

> It's difficult to conclude anything other than murder-suicide. Is it possible it could have been an accident or a mistake by one of the pilots? How intention-proofed are engine cutoffs?

You have to pull the switches out (against a spring) to be able to move them over a notch and flip them. Not really something you can just mistake for another switch or bump into by accident. I'd liken it to turning off the ignition by turning the key while driving your car. Possibly something that could happen if you're really fatigued, but requires quite a mental lapse.

[deleted]

Re: Preliminary report into Air India crash released

#293
post #179

Earlier quoted context omitted.

Above commenter said _quickly_, not simultaneously

Jesus... joey: Can you switch them quickly? snypher: You can do them with one hand. [Ed. This is ambiguous and could be read as "one hand, simultaneously". In fact, doing it with one hand non-simultaneously would be a weird claim to make of a simple knob. See also ajb's comment below.] zihotki: Really? They are not close together and have a spring mechanism. [Ed. Seems to believe snypher is claiming simultaneous oper…

> This is ambiguous and could be read as "one hand, simultaneously"

Not within the context of the thread.

Re: Preliminary report into Air India crash released

#294

> 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…

> It's difficult to conclude anything other than murder-suicide. You're leaping into the minds of others and drawing conclusions of their intent. One of them moved the levers. It could've been an unplanned reaction, a terrible mistake, or it could've been intentional. We may never know the intention even with a comprehensive and complete investigation. To claim otherwise is arrogance.

> One of them moved the levers. It could've been an unplanned reaction, a terrible mistake, or it could've been intentional.

Fuel levers are designed to only be moved deliberately; they cannot be mistaken for something else by a professional pilot. It's literally their job to know where these buttons are, what they do, and when to (not) push them.

It's not arrogance to assume the most likely conclusion is true, despite how uncomfortable that outcome may be.

Re: Preliminary report into Air India crash released

#295
I just want to call out that, whatever the facts of this case, pilot heroism is way more common than pilot murder. This is off the top of my head, so don't quote me on the precise details, I'm probably misremembering some things. But a few of my favorite examples:

- British Airways 5390: An incorrect repair causes the windshield of a plane to be blown out mid flight. A pilot is nearly sucked out. The head flight attendant holds onto his legs to keep him in the plane. The copilot and flight attendant think he is dead, but they keep the situation under control and land the plane.

Everyone survives - including the pilot.

https://www.youtube.com/watch?v=rGwHWNFdOvg

- United 232: An engine explodes in the tail of an MD-10. Due to rotten luck and weaknesses in the design, it takes out all three of the redundant hydraulic systems, rendering the control surfaces inoperable.

There's a pilot onboard as a passenger who, it just so happens, has read about similar incidents in other aircraft and trained for this scenario on his own initiative. He joins the other pilots in the cockpit and they figure out how to use the engines to establish rudimentary control.

They crash just short of the runway. 112 people die, but 184 people survive.

https://www.youtube.com/watch?v=pT7CgWvD-x4

- Pinnacle 3701: Two pilots mess around with an empty plane. They take it up to it's operational ceiling. While they're goofing off, they don't realize they're losing momentum. They try to correct too late and cannot land safely.

In their last moments they decide to sacrifice any chance they have to survive by not deploying their landing gear. They choose to glide for the maximum distance to avoid hitting houses, rather than maximizing how much impact is absorbed. They do hit a house but no one else is killed.

https://www.youtube.com/watch?v=DCMmCekKO_c

Re: Preliminary report into Air India crash released

#296
post #157

Why can the pilot shut off the fuel during takeoff?

What you are really asking is: would we, the passengers, be safer without human pilots? Eventually, yes. Soon? Maybe.

Dog and a pilot. The pilot is there to make sure everything is ok and the dog is there to bite the pilot if he tries touching anything

Re: Preliminary report into Air India crash released

#297

It's safe to state these fuel cutoff switches aren't to be touched in-flight unless the word 'fire' is said beforehand. Even then, you only perform fuel cutoff for the flaming engine. If the copilot was busy with takeoff, there is exactly one other person in the entire world that could have flipped both switches. We may never know which one flipped them back.

Fire isn't the only instantly severe problem with engines. Another is violent shaking if, say, part of the rotating assembly came off.

Yep. Fan blade off, shroud separation, HP disc separation, compressor stall, FOD ingestion/bird strike, EGT rise, oil system issues. Very unlikely events but still possible events that need a prepared response to and capabilities to manage the aircraft. The presumption is that the crew is trained, diligent, disciplined, and concerned with survival. Without that, aircraft would need to be unmanned and flown by AI lacking in ability to handle any unforeseen events creatively.

Re: Preliminary report into Air India crash released

#298
post #9
post #7

Earlier quoted context omitted.

Not accessible. Have they heard about S3 ?

It loads for me, so I think the link will be useful for some people at least.

It's getting hugged by the world and they didn't use a CDN apparently.

Re: Preliminary report into Air India crash released

#299

> 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…

Or a mechanical failure

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

Re: Preliminary report into Air India crash released

#300

Earlier quoted context omitted.

Jesus... joey: Can you switch them quickly? snypher: You can do them with one hand. [Ed. This is ambiguous and could be read as "one hand, simultaneously". In fact, doing it with one hand non-simultaneously would be a weird claim to make of a simple knob. See also ajb's comment below.] zihotki: Really? They are not close together and have a spring mechanism. [Ed. Seems to believe snypher is claiming simultaneous oper…

> This is ambiguous and could be read as "one hand, simultaneously" Not within the context of the thread.

Context is both these switches being turned off with a 1 second gap. Doing it with one hand simultaneously would possibly explain it, otherwise it doesn’t seem relevant.
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