Posts about: "Dual Engine Failure" [Posts: 270 Pages: 14]

Indian press seems to be running with reports of power loss, double engine failure. Not sure how accurate it is, but the video doesn't sound like a large jet a full power considering you can hear a lot of ambient noise around. At the start of the video the body angle is definitely low, low like they are trying to stay unstalled, but then the nose rises as the ground approaches, as you would expect anyone to react.

No speculation as to what caused the crash, but a couple of points. If there was an inadvertent retraction of flaps instead of gear, this could potentially be remedied by reselecting flaps promptly once recognised. Whether the startle factor would allow it is another thing.

If the RAT is indeed out and there was some sort of powerplant issue, ie. double engine failure, I don't think I would be in a hurry to retract the gear either. In fact it may well have been put down again in that scenario.

Regardless, awful footage to watch. RIP.

Dual engine failure due to fuel contamination?

or birds?

Double engine failure could point to a fuel problem (amongst many other potential causes).

A few have suggested double engine failure due to contaminated fuel, but we've seen historically that the equal likely (or perhaps more likely) reason for a double engine "failure" is accidental shutdown of the wrong engine.

True. We won\x92t know until the CVR and Flight Data recordings have been analysed. I think these will give a clear indication of what happened. The airport has reopened so I assume there\x92s no fuel contamination risk.

Just for the record, there is no system on modern Boeing aircraft to prevent the accidental retraction of flaps when too low or slow when airborne. You wouldn't even get a warning on Boeing aircraft that is related to Flaps, you'd eventually get one related to Low Speed or Stall. The Airbus has a safety feature called "Alpha-Lock" which physically stops the Flaps from moving when the AoA or speed? is deemed too low. But that's not a safety net for all flap settings, just the lowest for takeoff. It will save the day in 95% of situations though Mr Boeing (hint hint)

Takeoff config warnings and checklists may not have helped if the flap setting was not enough given the weight and conditions. A good handling pilot could recover from an incorrect flap setting (providing there's no obstacles to deal with), by gently lowering the nose allowing the airspeed to build up before resuming the climb. However, various human factors such as startle and over reliance on automation (my thrust setting must be good) will not help the situation.

In order of likelihood:

1.) Flaps moved instead of gear
2.) Incorrect Flap settings and inability of crew to recover from that
3.) Double engine failure
4.) Some electrical event that distracted them

Item 1) On the 787, is the gear lever on the main panel facing the flight crew, or on the centre console? I'd imagine they'd (flap and gear levers) need to be adjacent to each other for that to happen. All good points though.

Just to confirm.
The 787 is an aircraft which likes to, performance wise, use all of the available runway for takeoff. Sometimes you can be sat in the 787 and as you are rolling down the runway, you start wondering if Rotate has been called or not. It loves taking up all of the runway.

Nevertheless, there are some interesting speculations over on X. One guy even claimed the Captain was in the lavatory during the accident...

Many people have noted what appears to be the RAT deployed in the video footage suggesting dual engine failure. Possible wrong engine shutdown? But who diagnoses and actions an engine failure and shutdown below 400ft?

TE Flaps are extended, flap gaps between the wing and the flap element are observable. This is not an aberration of the spoiler position, you can see the nacelles through the gap, and that means the flap can not be in the retracted position.

An error of the TE flap deployed position, say between flaps 5 or 15 is not going to cause a stall event.

The flap has not been retracted instead of the gear.

Double engine failure... India. birds, always a latent threat. No rudder deflection, no aileron deflection, so it's not a SE problem, any engine issue is affecting both engines.

Pitch control and roll is not compromised in the video. The crew put out a mayday, not sounding like an electrical fault or distraction.

any funerals near by?

Incorrect TO thrust setting would not present in the video as recorded. Low thrust results in low acceleration, and extended distance to rotate. after rotate, low thrust results in low climb rate, and can result in the crew over pitching where the aircraft has obstructions that the crew have to avoid. the video appears to show the pitch increasing at a point where the aircraft is already unable to climb, not the other way round. An outside possibility.

For survivors, any from the aircraft will be a miracle, and mainly from the rear of the plane near door 3 area, if any. Plane is still striking tank traps at 70m/sec +, high ANU, it's not a high survivability event. Occupants in the buildings along the flight path will have a high fatality rate as well. This is going to be a high toll event in the aircraft and on the ground. Bad day at VAAH. RIP.

Like the dual engine failures that occurred on every aircraft which took off before it, using the same fuel supply?

😩

.... or a software failure. (ANa flight NH985)

You certainly should try that\x92s for sure. ANC and all that good stuff! In a panic it certainly is possible to just pull the wrong one. I\x92m not saying that\x92s what\x92s happened, to me it seems like dual engine failure, practically simultaneously.

No the plane barely took off the runway, low power setting/bad flaps. Unless you are saying a double engine failure before take off but seriously how likely is that? It's much more plausible to mess up the take off settings we have seen it many times before. But I think we will find out soon, no need to speculate too much.

But why is the RAT extended? Any 787 drivers able to confirm under what conditions the RAT automatically deploys?

Well, the certainly sound like they are working; failed engines sound different. No sign of smoke or damage either.

Conceivably, it could be a double engine failure but that's very unlikely.

The chances of a double engine failure on take off are like a billion to one, and I think are certified to a million to one occurrence.

As you say they still provide power and pressure even if not running

Doesn't work like that, and significant logical errors have been made on that basis in the past. The chances of simultaneous independent engine failure might be a trillion to one, being a million million.
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But failure is often not independent. Hit a flock of birds with both engines, run out of good fuel, etc etc - then the probability is primarily that of the root event.
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Edit: I make no comment on whether they were running or not in this case, only the statistics

I think it may be a simple case of inaccurate takeoff performance data, or inadvertent retraction of flaps instead of gear (this can happen and does happen).

I'm no expert and open to discussion, but it looks to me like the slats are somewhat extended but the flaps weren't, or at least not from the angles we have seen so far. The autogap system on the B787 will automatically extend the slats if they are already in the middle position (i.e Flaps 1) with KIAS <225. Perhaps, either the inaccurate input for takeoff performance produced figures that allowed a Flaps 1 departure, leading to a longer takeoff roll and then once out of ground effect, insufficient climb gradient and a pilot induced stall. Alternatively, at the point where you would likely ask for gear up, the PM has inadvertently selected Flaps 1 from Flaps 5 leading to the same effect. Pilots experienced startle and shock, declared a Mayday as they knew they were descending when they shouldn't be and didn't have time to appropriately react.

Dual engine failure is obviously a possibilty however rare it might be. but it doesn't look like any catastrophic failure from the video. Clearly a sad day for all in aviation and looking forward to the official investigation and results, hopefully something we can all learn from.