Posts about: "Fuel (All)" [Posts: 1028 Pages: 52]

Yes, that is clearly what he is trying to make. The point I make is this: that point rests almost entirely on the CVR conversation happening very shortly after the switches are activated and there being a long pregnant pause before they are switched back. Had the cutoff been inadvertent (mistaken action by PM or mechanical) and it took them 8 seconds to work it out (which is quite reasonable under the circumstances), the switching of them back on 2 seconds later could equally be an entirely consistent timeline.

The report has not identified who said those words and when. I find this curious as it's pretty easy to count back the seconds from the end of the CVR recording or forward the application of full power.

Great comment by GroundedSpanner in post 561 Preliminary Air India crash report published
The switches act on multiple circuits. A single electrical / electromechanical fault shutting down both engines is Extremely Improbable.
A few more observations on switch comments in this thread:
Liquid spillage - Switches are sealed so highly unlikely and not both at once.
Switches between detents \x96 The surface the locking \x93pips\x94 sit on is slightly curved. You can get the switch to sit on it but only with difficulty. I can see no way how both could be in this position accidentally.
Naming \x96 These are normally called a \x93locking toggle switch\x94.
It is a difficult design problem. You have to have a means to shut off the fuel but a single fault should not shut the off OR stop you shutting it off.
(I design fuel control systems for CS 25 aircraft).

As reported yesterday by the FT

The US Federal Aviation Administration has issued a notice to its international counterparts that fuel control switches in Boeing aeroplanes like the Dreamliner involved in last month\x92s fatal Air India crash do not pose a safety issue.

The FAA\x92s notice to foreign civil aviation authorities followed a preliminary report by India\x92s Aircraft Accident Investigation Bureau that the engines on Air India Flight 171 briefly cut off shortly after take-off on June 12.

Two separate fuel switches set to cut off, at one of the most critical phases of flight where doing so would lead to an unrecoverable situation, followed by one pilot asking the other why he set the switches to cut off.

No AD from Boeing or NTSB.

Come on.

Given that there's no evidence that the Fuel Cut-off Switches, or indeed any other part of the aircraft functioned incorrectly, what exactly should such an Airworthiness Directive be saying?

I might be wrong but I imagine the OP is referring to the elephant in the room.

Once in a bazillion, eh?

It seems more passengers are dying in scheduled flights in recent times due to pilot suicide than any other cause - and people still want to argue about whether it was suicide or an accident after the fact.

The simple fact is it would likely have 'solved' this accident by now. We'd know if the fuel switches were operated by a crewmember. We'd know which crew member. We'd know who asked who "why'd you [go to] cutoff?", we'd know if there was any physical activity between the two before or after the engine shutdown and we'd (probably) know if there was any indication or external reason for them to do so that isn't captured on the DFDR or CVR. The ATSB raved about the ability to recover video footage in the R66 prang - and that was a single-pilot helicopter that was fitted with it, one could only speculate how much the accident investigators would have liked to have it here...

So...I ask this as a genuine question - why are pilots so fearful of being video'd at work when virtually every other industry - particularly transport related industries - has at least CCTV, if not more intrusive methods of surveilling their employees? In my last company, we had real-time In Vehicle Monitoring Systems , Dashcam's and Cat Driver Safety Systems in our light vehicles, FFCCTV and dataloggers and IR detectors in the locomotive cabin to detect movement, CCTV throughout the shunting yard and car dumpers as well as the datalogging of the signal system and radio communications - and that was just a train company. And the notable thing about all this surveillance is, several times, I was able to demand the relevant evidence be downloaded and it cleared me of an allegation of wrongdoing. In part, due to the lack of protections afforded us in rail when compared to the legislation guarding use and disclosure of the CVR that exists in aviation.

Can anyone articulate a specific reason or their grounds for not wanting CCTV in the flight deck - and not just a catchall "it's a hostile work environment" - what makes it hostile in your view? Why do you feel it's acceptable to be filmed in the aerobridge but not the flight deck? The fact they can watch you screwup instead of just listening to you screwup? The fact you can't hide anything that goes on behind the closed door after an accident? What specific articulatable reasons do pilots have for not wanting to be captured on CCTV in their workplace like so many other employees around the world take for granted every day?

One engine started to accelerate from the minimum speed reached. While that may have reduced drag very slightly I doubt it changed the impact point of the aircraft more than a few meters. The time from cutoff to run on the number 1 engine was 19 seconds before impact.

SLF here but an engineer who has spent most of his working life solving problems of one sort or another.
Would the FO, who is flying the aircraft (and presumably looking more or less straight ahead), notice out of the corner of his eye the Captain leaning over to move the fuel cut offs? Would that glimpse coincide with the loss of power? Is that when the comment "why did you do that" was made? Did he actually see the switches being turned off by the PIC or just assume that they had been, based on the aircraft performance loss?

I'm assuming that directly the engines lost power the FO would start looking for a cause. Where in the list of possible causes would the FCS be? Would he look down and see them in the "wrong" position fairly quickly (based on his "view" of the PIC leaning over) or would there be a more common reason for the loss which he would look at first?

He would have had to have had a reason to go straight to the FCS as the cause, surely? Further, what would be your reaction (as a pilot flying) to your colleague turning off the switches (again, not a remotely normal course of action). I think that mine would be something along the lines of "What the h*ll do you think that you're doing?" and maybe even reach down to turn them back on himself (which may indeed be what happened)
Sorry if this is badly worded, but I'm sure that you get my drift.

Pilot error.. flown 777 and 787 for years now, these fuel control switches don't bounce about and it takes a positive action to move them to cut off.. FO was PF and Captain probably got confused by throttles rolling back and started double loss of thrust memory actions... but at low altitude? what on earth ? Thrust levers were "fully forward " according to report so some attempt to squeeze the juice... of course if it was something more sinister with no audio on the CVR we will never know.. sadly

I think there's a good chance that there might be mandated CCTV in cockpits in the future as a consequence of this accident. There's also near enough to a 100% chance it would not and could not prevent this type of accident, but "accident prevention" will be the reason given. It always makes me curious how knee-jerk regulatory actions get justified. I don't care that much if they do install it - the worst that could happen is I get sprung picking my nose. But I do care when authorities or Governments issue nonsense reasons for it in an effort to be "seen to be doing something" by the public.

I'm late to the party here (deliberately) but I'm slightly surprised there seem to be quite a few commenters not acknowledging the elephant in the room after this report. I spent years on the B767 and the B744 before moving to Airbus. These are big chunky switches requiring two different muscle actions to change their position. "Accidentally" moving them from run to cutoff with a neat 1 second split is extremely improbable even at the best of times, and makes no sense at all during the first moments of the takeoff phase. The hypothesis which does make more sense based on the facts now available is just a bit disturbing to mention, but that's unfortunately where we are at the moment.

Even if the engine would have accelerated to TOGA - no way to fly you out of that situation being near stall speed far below Vmca, with no altitude to trade for speed on one engine.

I have flown as a copilot with Indian captains, and as a captain with Indian copilots. I have no negative comments about Indian pilots, and \xabauthority gradient\xbb was not an issue.
The fuel switches will not move by themselves. Electrical gremlins will not change the switch position. One pilot asked the other why he moved the switch(es). It was done manually.

So WHO and WHY is the question. That leads further to done with intent or done without intent.

We can safely say that at the moment, WE DON’T KNOW.

This is not a competition.

The report doesn't give us the words one pilot used to ask why he did the cutoff, nor the words used by the other pilot to explain that he didn't, nor any indication of the tone of either pilot or even who said what. Some people *believe* that it was co-pilot Clive Kunder who asked why the switch was cutoff, but only because he was PF and would/should have had both hands on the control column during take-off, leaving the captain/PM Sumeet Sabharwal to be the one who cut the switches, but this is very far from conclusive. The investigators will know exactly who said what and when, so it is very strange that it is left out of the report, but is not evidence of anything in itself.

The only distinction the report makes is that the question was 'why did you cut off' rather than 'did you cut off', which suggests one of the pilots saw the other cut the switches, which in turn suggests either (a) the pilot who did the cutoff had done it accidentally and wasn't aware of it, or (b) the pilot who did the cutoff was well aware of what they did but then lied about it despite having clearly been seeing doing it.

Given the question was 'why', it seems equally plausible that it was the PF Kunder who transitioned the switches accidentally as part of some muscle memory blunder, and it was the PM Sabharwal who asked Kunder why he cutoff, who then replied that he didn't, because the fact he'd made the mistake hadn't registered.

OTOH, it might just be a sloppy transcription.


I totally agree with this, it makes no sense at all, especially after his 'just one or two more flights' statement. The guy had already moved cities to help look after his father, and was considering retiring early to have even more time to dedicate. Again, for me, this points to a blunder by Kunder.

The fact that nobody apparently announced 'engine failure' as per training, but instead asked why the switches were in cut-off, speaks volumes. No need to labor the incredibly improbable double switch failure any further in my humble opinion.

So far so good.

Three seconds after lift off, setting initial climb attitude, you suggest that the PF is/was moving his hands ...where?
Walk me through how and why that happened/happens. The training and CRM implications of what you propose are pretty serious...for that airline.
Yes, the vague (in points) language used has elicited a lot of comment.
Not sure why you appear to want to throw the FO under the bus.

What basis do you have for asserting that the switches were missing a locking spring? You are apparently making this up.
Why?
(We had a similar switch on an aircraft I flew some decades ago, and if the spring wasn't working You Replaced The Switch!)

Your previously expressed hypothesis - long sleeve cuff catching on them, and then one at a time this sleeve cuff pulling on each, and then (despite the physical sensation of catching on them and the CM checking to see what the hang up is) changing the position of the switches accidentally - could be easily tested in the simulator.
The investigation team has had between 20 and 30 days to look into that possible explicit accidental switch triggering path.
You seem wedded to it.
Why?
Do you believe that they have, or have not, considered it?
(Part of the reason that I ask this is that the next expected hand movement would probably be forward, not aft, toward the gear handle to raise the gear, in anticipation of a positive rate of climb being called out since they just took off and the PF was setting the climb out attitude...)

While the chance of a pilot committing suicide and multiple murders is extremely low, there are six examples of pilots letting their Airbus, Boeing crash on purpose.
Logical thinking by a pilot murdering his passengers, crew and himself is non existent.

Suicide is the number one likely cause of this crash. Fuel control switches do not move by itself of an iPad hitting it. A pilot needs to move the switches by hand.
I cannot find any other cause for this crash. Especially the question ' why did you move the switches' is extremely suspicious. I bet the captain said that. He was the only one with his hands free to move the switches.

Former Boeing Engineer who was in the room for some 787 AD discussions.... What exactly would you expect Boeing to put in the AD? "Don't put the fuel switches to cutoff unless you really mean to"? Let alone ADs are not in anyway a method for pilot training or actions, they are for the airline engineering and maintenance teams. What would you think Boeing should ask airlines to do in this proposed AD?

I'm sure the current team has already done the systems analysis to see if there was any possible way these weren't completely isolated systems (which I'm pretty confident they are). Let alone the initial report categorically says at this point there are no design issues found with Boeing or GE.

I don't think the intention in your quoted post is to suggest there should be an AD - more a "come on, it's obvious" statement I think.

I said earlier that I don’t think this is what the OP is suggesting…he’s pointing out that given the preliminary report and the fact that there is no AD from Boeing, it’s highly likely that the switches were moved by someone on the flightdeck and not a problem with the switch itself.