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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

#601

Post by CPLX »

testemailfordg2 wrote: post #562

Three things:- 1) Pilot clearly said I didn't do it. 2) Report talks about the second switch being turned off in a second. 3) Known advisory on switches getting flipped. If you see these three together, it becomes easy to deduce that based on point 2, switch was not human induced as the actions required take more than a second. Next the third point, advisory was for this exact scenario which played out, though rare b…

> it becomes easy to deduce that based on point 2, switch was not human induced

This just isn’t correct at all. The evidence isn’t conclusive but if a human operated switch was flipped, and one of the humans present says to the other one hey why did you do that, then Ockham’s razor points to a human flipping the switch.

It’s not the only option, but it’s certainly the most likely.

Re: Preliminary report into Air India crash released

#602

Post by labcomputer »

fosk wrote: post #493
bestouff wrote: post #483

Earlier quoted context omitted.

Airbus liners don't allow cutting fuel with trust lever on.

This is actually very clever and elegant!

Well.. except that it means you can’t turn off the engines if the throttle encoder fails.

Re: Preliminary report into Air India crash released

#604

Post by labcomputer »

melenaboija wrote: post #379
Yokolos wrote: post #359

Earlier quoted context omitted.

Engine fire requires you to cut fuel to the affected engine.

Is cutting off fuel while taking off a better solution than letting them burn?

It is if you don’t want the wing spar to fail!

Re: Preliminary report into Air India crash released

#605

Post by bgwalter »

bonoboTP wrote: post #577
dubcanada wrote: post #461

Earlier quoted context omitted.

No neither black box stores video. One stores audio on flash memory and the other stores flight details, sensors etc. I don’t think video is a bad idea. I assume there is a reason why it wasn’t done. Data wise black boxes actually store very little data (maybe a 100mbs), I don’t know if that is due to how old they are, or the requirements of withstanding extremes.

In the US, the NTSB has been recommending it for over 20 years. The pilot unions have been blocking it, due to privacy and other things. I'm not in aviation. But my between-the-lines straightforward reading is that unions see it as something with downsides (legal liability) but not much upside. It could be that there are a million tiny regulations that are known by everyone to be nonsensical, perhaps contradictory or…

Airlines would certainly try to surveil regularly, but if the video data is only sent to the sealed FDR, they'd need to tamper with the system.

Additionally, footage could be encrypted with the NTSB having the keys.

Or simply make it a crime to use the footage in non-accident situations (this should be applied to other forms of surveillance, too ...).

Re: Preliminary report into Air India crash released

#606

Post by hwillis »

testemailfordg2 wrote: post #562

Three things:- 1) Pilot clearly said I didn't do it. 2) Report talks about the second switch being turned off in a second. 3) Known advisory on switches getting flipped. If you see these three together, it becomes easy to deduce that based on point 2, switch was not human induced as the actions required take more than a second. Next the third point, advisory was for this exact scenario which played out, though rare b…

The switches are right next to each other and have a very short throw[1]- it would definitely be possible to do them in under a second and it looks possible to throw them together.

IMO that looks like a spot that would be pretty difficult to hit accidentally even if the ward failed. You'd have to push them down and the throttles are in the way.

Doesn't mean the switch couldn't have failed in some other way- eg the switch got stuck on the ward but was still able to activate with a half-throw, and spring pressure pushed it back into off during a bump. But switches generally only activate when fully thrown, and failing suddenly at the exact same time is not really what you would expect.

[1]: https://www.reddit.com/r/indianaviation/comments/1lxra3g/b78...

Re: Preliminary report into Air India crash released

#607

Post by rainsford »

bonoboTP wrote: post #588
testemailfordg2 wrote: post #562

Three things:- 1) Pilot clearly said I didn't do it. 2) Report talks about the second switch being turned off in a second. 3) Known advisory on switches getting flipped. If you see these three together, it becomes easy to deduce that based on point 2, switch was not human induced as the actions required take more than a second. Next the third point, advisory was for this exact scenario which played out, though rare b…

> as the actions required take more than a second Where do you get this from? You have to pull up the switch with two fingers and move it to the other position and put it back in. This doesn't seem to take more than a second if deliberate. To me, it points to a Germanwings-style sabotage. And the "I didn't do it" seems to be a lie. Not very confident in it, just the likeliest to me. Though one can ask why not just pu…

> And the "I didn't do it" seems to be a lie.

As has been pointed out elsewhere, even if one of the pilots did deliberately move the switches, it's not clear from the reporting so far if that's the same pilot who responded to the question. In other words, it's possible one pilot flipped the switches and then asked the other pilot why he cut off the fuel to misdirect and create more confusion.

Edit: Of course this is all speculation, we don't know if the switches were moved deliberately and if so which pilot did so and which pilot was which in the exchange. More investigation is clearly needed.

Re: Preliminary report into Air India crash released

#608

Post by dr_ »

testemailfordg2 wrote: post #562

Three things:- 1) Pilot clearly said I didn't do it. 2) Report talks about the second switch being turned off in a second. 3) Known advisory on switches getting flipped. If you see these three together, it becomes easy to deduce that based on point 2, switch was not human induced as the actions required take more than a second. Next the third point, advisory was for this exact scenario which played out, though rare b…

1) but what else would they say if they did do it?

Re: Preliminary report into Air India crash released

#609

Post by 18172828286177 »

testemailfordg2 wrote: post #562

Three things:- 1) Pilot clearly said I didn't do it. 2) Report talks about the second switch being turned off in a second. 3) Known advisory on switches getting flipped. If you see these three together, it becomes easy to deduce that based on point 2, switch was not human induced as the actions required take more than a second. Next the third point, advisory was for this exact scenario which played out, though rare b…

In this phase of flight the pilot’s hands should be nowhere near the thrust levers let alone the fuel cutoff switches. There is no way they could accidentally knock them with their hands.

Re: Preliminary report into Air India crash released

#610

Post by vishnugupta »

shash wrote: post #530
vishnugupta wrote: post #433

Earlier quoted context omitted.

The pilot is toggling the switch on. Toggling it off presumably requires more power and is multiple actions.

You move those switches down apparently. I don't think so.

Up/Forward ==> Run ==> Fuel supply is on

Down/Backwards ==> Cutoff ==> Fuel supply is off

https://www.reddit.com/r/indianaviation/comments/1lxxatc/fue...

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