UK bound plane crashed in India moments after takeoff

[stealthn]

I’m surprised they haven’t released info from the black boxes yet?

[javadog]

Originally Posted by jyl

Interesting! But the logic wouldn’t shut off engines just because the plane thought it was on the ground, would it?

That's been discussed at length and I don't think it will pan out. A summary of posts on that topic that you can read, if you want:

https://paulross.github.io/pprune-threads/gh-pages/AI171/Weight_on_Wheels0.html

[javadog]

Originally Posted by stealthn

I’m surprised they haven’t released info from the black boxes yet?

As i mentioned earlier, it has been reported that a preliminary report is supposed to be put out in the next week or two that will have some info from them. We'll see if it actually happens.

[javadog]

Originally Posted by jyl

What airlines should one think about avoiding?

That's a question with a long answer. I'll try to find the time to write it out but no guarantees...

[afterburn 549]

Anything not taken care of in the 50 states, and that's not a great guarantee.
Here, the FAA has authority.
Anywhere else? I don't know.

[450knotOffice]

The engines of modern jetliners are controlled by Full Authority Digital Engine Controls - FADECs. There are two identical channels per FADEC, one controlling the engine, and one standing by in case of any issues with the first one. FADECs are powered independently of the rest of the airplane, powered by their own Permanent Magnetic Alternator (PMA) mounted on the respective engine (which begin to supply power to the FADECS almost as soon as the starter begins to spin the engines up for start). This allows the engines to continue to run normally and be controlled normally by the Throttles or Thrust Levers (Boeing vs. Airbus terms) regardless of what sort of electrical issues may be happening within the airplane itself.

[greglepore]

Originally Posted by 450knotOffice

The engines of modern jetliners are controlled by Full Authority Digital Engine Controls - FADECs. There are two identical channels per FADEC, one controlling the engine, and one standing by in case of any issues with the first one. FADECs are powered independently of the rest of the airplane, powered by their own Permanent Magnetic Alternator (PMA) mounted on the respective engine (which begin to supply power to the FADECS almost as soon as the starter begins to spin the engines up for start). This allows the engines to continue to run normally and be controlled normally by the Throttles or Thrust Levers (Boeing vs. Airbus terms) regardless of what sort of electrical issues may be happening within the airplane itself.

But...and you certainly know much more than I do...are the other systems that interface with the fadec glitch proof-it seems the automation on the 787 is layered on top of the facec somewhat and transmits commands to the fadec...or am I mistaken? IE the "on ground" sensors require power, and the tcma needs a command from somewhere to indicate settings, so if those imputs are power interrupted could it corrupt the logic being applied by the fadec, which had normal power regardless?

[jyl]

WSJ

“The investigation into last month’s Air India crash is focusing on the actions of the jet’s pilots and doesn’t so far point to a problem with the Boeing 787 Dreamliner, according to people familiar with U.S. officials’ early assessments.”

“Preliminary findings indicate that switches controlling fuel flow to the jet’s two engines were turned off, leading to an apparent loss of thrust shortly after takeoff, the people said. Pilots use the switches to start the jet’s engines, shut them down, or reset them in certain emergencies.”

“Preliminary findings indicate that switches controlling fuel flow to the jet’s two engines were turned off, leading to an apparent loss of thrust shortly after takeoff, the people said. Pilots use the switches to start the jet’s engines, shut them down, or reset them in certain emergencies.”

The report by the publication “The Air Current” is subscription only but this free to read article has some detail

https://gulfnews.com/business/aviation/air-india-787-crash-caused-by-fuel-switch-mistake-investigators-find-critical-clue-1.500192693

This explanation, if true, seems hard to comprehend.

[edgemar]

It does seem consistent with what happened after it took off.

[A930Rocket]

So why would they turn the fuel off at take off?

Are the switches near something else and they inadvertently turned them?

[Jeff Higgins]

Originally Posted by jyl

WSJ

“The investigation into last month’s Air India crash is focusing on the actions of the jet’s pilots and doesn’t so far point to a problem with the Boeing 787 Dreamliner, according to people familiar with U.S. officials’ early assessments.”

“Preliminary findings indicate that switches controlling fuel flow to the jet’s two engines were turned off, leading to an apparent loss of thrust shortly after takeoff, the people said. Pilots use the switches to start the jet’s engines, shut them down, or reset them in certain emergencies.”

“Preliminary findings indicate that switches controlling fuel flow to the jet’s two engines were turned off, leading to an apparent loss of thrust shortly after takeoff, the people said. Pilots use the switches to start the jet’s engines, shut them down, or reset them in certain emergencies.”

The report by the publication “The Air Current” is subscription only but this free to read article has some detail

https://gulfnews.com/business/aviation/air-india-787-crash-caused-by-fuel-switch-mistake-investigators-find-critical-clue-1.500192693

This explanation, if true, seems hard to comprehend.

I agree. Impossible to comprehend, really. Too many redundant safety systems for this to have happened. It's not like a gas tap on an old motorcycle.

[Magyar Kiwi]

"So why would they turn the fuel off at take off?
Are the switches near something else and they inadvertently turned them?"

Major human error, or
Sabotage.

Pic below:
Cheers

[javadog]

Originally Posted by A930Rocket

So why would they turn the fuel off at take off?

Are the switches near something else and they inadvertently turned them?

No, they require a deliberate effort to change positions. They are not regular toggle switches, they are blocked from movement unless you first lift them over a detent, in either direction.

Much depends on whether the thrust was lost first. If so, then they probably cycled the switches as part of an engine restart procedure. Boeing training prohibits such an action until they have gained at least 400 feet above the runway, the IA manual may have something different to say. They didn't have enough airspeed or altitude for an engine restart, if that's what they did. And, it wouldn't explain the initial loss of thrust.

If the switches were moved before the loss of thrust, I can't imagine why.

They may release more info today.

[edgemar]

The aircraft had reached an airspeed of 180 knots when both engines’ fuel cutoff switches were “transitioned from RUN to CUTOFF position one after another with a time gap of 01 sec,” according to the report.

“In the cockpit voice recording, one of the pilots is heard asking the other why did he cutoff. The other pilot responded that he did not do so,” the report reads.

Shortly after, the switches were reversed back to where they should have been, and the engines were in the process of powering back up when the crash happened.

[herr_oberst]

"Ending weeks of misinformation and AI slop"

[javadog]

Well, that’s f’ing bizzare…

[jyl]

Liftoff at 8:08:39, fuel switches moved to CUTOFF starting 8:08:49, a second apart. 8:08:52 switch 1 was moved back to RUN, 8:08:56 switch 2 was moved back to RUN. Data recording stopped at 8:09:11.

So two seconds after second switch was moved to CUTOFF the first switch was moved back to RUN and four seconds later the second switch was moved back to RUN.

Report doesn’t say when the conversation described above took place, doesn’t mention other conversation or noises, I am thinking about noises of a struggle. I assume investigators can figure out who said what and infer who moved the switches to CUTOFF. Co-pilot was flying, pilot (the senior guy) was monitoring.

This is insane.

https://aaib.gov.in/What%27s%20New%20Assets/Preliminary%20Report%20VT-ANB.pdf

I guess everyone who knew or had contact with the pilots will be questioned.

[Steve Carlton]

At 10:20 in the video, he mentions a recommended inspection for the fuel cutoff switches due to the locking mechanism not working on 737s with similar switches. Air India did not do the inspection. Seems more likely to me they were cutoff inadvertently, or maybe someone was committing suicide, effectively. Due to the crash damage to the switches, we may never know. I suspect switch inspections will soon become mandatory.

So, all the electrical issues were a result of the engines being cutoff? Seems like the design of these switches is wanting.

[Alan A]

They should have bought the extended warranty…



Too soon?

[A930Rocket]

Read this tonight…

The Indian agency’s report said that the US Federal Aviation Administration had issued an information bulletin in 2018 about “the potential disengagement of the fuel control switch locking feature”.

Though the concern was not considered an “unsafe condition” that would warrant a more serious directive, Air India told investigators it did not carry out suggested inspections as they were “advisory and not mandatory”.