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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

#391

Post by WalterBright »

dyauspitr wrote: post #321
WalterBright wrote: post #253

Earlier quoted context omitted.

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.

Would it matter in this case since you would crash either ways. I’m talking about protection in a very specific situation where you make it harder to shut off both engines when you’re very close to the ground.

If the ground you are over is a good landing spot, your best chance is to cut off the fuel to that engine ASAP.

Re: Preliminary report into Air India crash released

#393

Post by Dylan16807 »

gnulinux996 wrote: post #177
ssl232 wrote: post #35

Earlier quoted context omitted.

> EDIT: Why is there no Cockpit Video Recorder? The days of limited storage are over. Pilots unions are dead against it.

Are you actually using a tragedy like this to launch an assault on organized labour?

What, do you want them to hem and haw and refuse to answer?

Saying the union drove a decision is hardly "an assault on organized labor".

Re: Preliminary report into Air India crash released

#394

Post by Aeolun »

burnt-resistor wrote: post #326
sugarpimpdorsey wrote: post #294

Earlier quoted context omitted.

> 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, despi…

> cannot be mistaken for something else Assumption. Big ass assumption. Pilot are trained until actions are instinctual and certain memory items are almost unconscious. But pilots are still people and people are fallible and make mistakes, and sometimes act unreasonably. Intent cannot be determined without clear evidence or statements because that's now how thoughts locked away in people's minds work. > It's not arro…

> You don't know this.

That it isn’t certain doesn’t change anything about it being pretty likely.

Unpleasant, but I suppose at least it means we won’t suddenly see other planes falling out of the sky due to fuel switches being set to off.

Re: Preliminary report into Air India crash released

#395

Post by Dylan16807 »

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.

> because of people like you

No. Bad.

Re: Preliminary report into Air India crash released

#396

Post by Aeolun »

ExoticPearTree wrote: post #313
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…

> 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.

Re: Preliminary report into Air India crash released

#397

Post by userbinator »

rogerrogerr wrote: post #265
anonymousiam wrote: post #260

Earlier quoted context omitted.

There would have likely been an indication on the glass cockpit displays that the fuel had been cut off, perhaps the pilot flying noticed this and asked the captain.

Yes, there is, but the reaction to that would be to look at the position the cutoff switches were in. We didn’t hear “wtf, they’re in Run” - the report says they just moved them from Cutoff to Run and the engines responded as expected. I think you have to really reach to make this not pilot error. I know it’s appealing to call this a Boeing problem, but the evidence just from this prelim report is very compelling. If…

Until we hear the actual CVR audio, I don't think we can assume much. They are under a very high stress at that point in the flight, and while the "WTF?" might be going through their minds, all they could've resorted to is toggling the switches off and on again.

Re: Preliminary report into Air India crash released

#398

Post by Gare »

0_-_0 wrote: post #381
sitharus wrote: post #351

Earlier quoted context omitted.

Or you simply interlock the engine cutoff with the thrust lever position, any position other than idle prevents shutdown. This all goes through the flight computers already. If there’s a fire or similar problem the fire handles will cut off fuel without the normal shutdown procedure, but the normal switches only need to be used at idle thrust. I wonder if Airbus has this logic, since their philosophy is to override t…

According to AI, Airbus places these switches on the overhead panel, so that alone would make it harder to inadvertently move them. Apparently, Airbus "protections do not extend to mechanical or FADEC‑controlled systems like the engine‑fuel shutoff valves. If you deliberately pull and flip the ENG MASTER lever to OFF, the FADEC will immediately close the LP and HP fuel valves and the engine will flame out. If you the…

Well, AI is plain wrong. Fuel cutoff switches on Airbus are in the same position as in Boeing planes, below the throttle.

Re: Preliminary report into Air India crash released

#399

Post by creato »

KaiMagnus wrote: post #354
snypher wrote: post #33

Earlier quoted context omitted.

There's a good photo of them here; https://theaircurrent.com/aviation-safety/ai171-investigatio... You can do them both with one hand.

I wonder if they could theoretically rest on top of the notch, not fully locked into either position and flip accidentally. No idea how the switches behave when not all the way up or down, but the notch looks pretty long and flat so it could be possible.

Something like this could maybe happen to one switch, it's unlikely but possible. But two independent switches at the same time?

Re: Preliminary report into Air India crash released

#400

Post by Aeolun »

ceejayoz wrote: post #13
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…

> 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. > As per the EAFR, the Engine 1 fuel cutoff switch tr…

> Damn. That's pretty quick to diagnose and take action.

I have to imagine that “You are flying” and “You just cut off all fuel to the engines” must generate a pretty obvious claxon of warnings.

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