Posts about: "Relight" [Posts: 106 Pages: 6]

There would have been multiple similar failures in different locations. The data for the EAFR is completely separated from the wiring and circuitry for the HP fuel valves. - And that on both engines.

That is nonsense. There is no "fuel cut-off module". The fuel cut-off HP valves are operated directly by the cut-off switches through simple latching solenoids. No computer involved, not part of any communication network of the plane. The FADECs (which itself are totally separated from the rest of the aircraft) only get information on the status of the switches; e.g. to faciliate engine restart.

Likely because the FDR readout showed the engines at the appropriate takeoff thrust, then the switches move, takeoff thrust goes away. Switches move back to RUN and the quick restart begins.

I am not aware of a part of the prelim report, second paragraph being discussed anywhere. Something I find, if I'm correct, not discussed yet for me surely very significant.
"The EGT was observed to be rising for both engines indicating relight. Engine 1\x92s core deceleration stopped, reversed and started to progress to recovery. Engine 2 was able to relight but could not arrest core speed deceleration and re-introduced fuel repeatedly to increase core speed acceleration and recovery . The EAFR recording stopped at 08:09:11"
Forgive my now 20 years into retirement as an F/O on the B737 400 and A320/21 but I still retain my lifelong avid interest in all things aviation. So am I correct in thinking this paragraph indicates significantly that eng2, right hand, core compressor had failed, albeit not explosively? It relit and fuel was being "re-introduced repeatedly "but could not arrest core speed deceleration". From day one I believed that no 2 failed after V1 and that the automatic correction for this on the 787 hid all but a possibly apparent small nose right on its climb out. Additionally I surmised that with all the warnings this produced, the low altitude and few seconds to address such a failure, the first recycle was offered up to the no 1 engine switch, in haste. The immediate result then RAT extension, a check on the engine parameters and an action on the no 2 switch, again in haste on realisation that was down on N2, then, sadly too late, No 1 recycled successfully. Unlike No 2. Heaven knows, a similar mistake was made on the Kegworth B737, when all he time in the world was available compared to AI171.
To me the long debate here about suicide is very unprofessional and surely this factual part of the report, has masses more credence, regardless of the consequences facing the AI crew.
If this bit about No 2 engine report is as I interpret, I would at least hope, if not already, someone else has picked it up, or at least it will get more attention ere long. God bless all the people so badly affected and I pray the cause will be one day revealed and not be buried to protect the money men. Has been known.

IF going for a dive why would you cut the fuel / engines?
The timing was such that the engines didn't have time to restart and develop thrust before impact. If switched later they would have done when the switches were re-set to run. We are highly unlikely to ever know if the timing considered this.

I posted a week or so ago, on the forums generally, suggesting that the moderation of the Air India threads had gotten excessive, and at that particular point, it might even be an opinion I stand by. But reading through the last 100+ posts, other than the above few comments, it's just garbage. I'm sorry, to those who think they're saying something meaningful, but it's just hot garbage.

For the legal types - stop quoting what is, and isn't, the burden of proof. This is a forum on the Internet. The topic being discussed is an international investigation into a plane crash. For both of those things, there is no possible relevance to the burden of proof in legal cases in <whatever your country is>.

For the psychologists (both actual ones and those pilots who are moonlighting as one) - stop quoting psychological theory. Many of us know it, others don't, but we all have such an incredible lack of information about the pilots concerned that it's pointless mentioning it, except in passing. No one has time for pages of guesswork or instructions to the investigators on what they should be looking at.

For the tech guys who are still talking about the possibility of malfunctioning switches, please, stop. The pilot saying "why did you do x" is not consistent with a switch failure, you don't say that just because of an unexpected run-down, you say something more generic, like "holy smokeballs, dual engine failure". The specificity of the comment implies clearly observed action, specific to the switches, which aligns with the data record.

For everyone - just because something isn't absolutely mathematically impossible does not mean you can or should bring it out and eat up pages doing so. Investigations do not have to cover every single possible "what if", because in an unlimited universe no investigation would ever conclude. What they have to do is come up with the most likely scientifically derived assessed outcome for an already fairly unlikely event. I can accept people saying "We don't know for sure that the switches were operated deliberately" even though that's probably more likely than not. I can't accept the kind of argument which isn't dissimilar to: "Maybe there was a flaw with the switch detent, and a book fell off the console, and the previous crew had spilled water on it, making it slippery, and before that when the console was installed it was 1.5 degrees more inclined than it should be, and that caused the rollback. I accept that we're already in "unlikely event" scenario, but once the impossible has been eliminated, refusing to accept that there's probably 2-3 likely scenarios left, and instead inserting incredibly unlikely theoretical stuff... well that's just bad faith.

Finally, it's personal taste, but I remain a bit disappointed with the deliberate blindness being applied to inconvenient truths by some on here. The two currently most likely rational explanations are simple - deliberate pilot action, accidental pilot action. Either way, it's pilot action . As frustrating as some of the wild theories are, the obfuscation being pushed out by the "circle the wagons" brigade is just as bad. Any pilot knows that their life - and those of their passengers - relies on clear sightedness and not avoiding uncomfortable data points. So let's trust our instruments. There should be no absurd rush to judgement but also, please, let's not hide behind the "they were professionals, treat them with respect" stuff, endlessly. Someone selected fuel on both engines to cut-off, mere moments after they left the ground. It won't be an engine restart procedure (too low, too early), it won't be some bizarre technical problem that hasn't happened in millions of flight hours on other 787s worldwide. The CVR says "why did you do X" and the data recorder says "X happened". The two line up. What we don't know for absolute certain is why, so the only sensible things now being examined are:

1) Deliberate pilot action (can only assume harmful intent at Vr + 3 sec)
2) Accidental pilot action (due to severe cognitive disconnect, or "wallet in freezer" stuff)

I'm one of many being frustrated by the lack of CVR recording being released, because that will almost certainly identify whether it was 1 or 2. But it would be abnormal for that to happen, and I respect that until they're sure, if the CVR points to something, they will want it confirmed before releasing it, because whether it's 1 or 2, it's bad news for the families of that particular pilot.

Oh, and to whoever said "Ask yourself if we are ready to hear it?".... come on. Hundreds of people died. Ignoring a piece of evidence related to that because it might be uncomfortable hearing it is unacceptable, and a bit childish. It might be uncomfortable, but professionals follow the evidence, wherever it may lead, however uncomfortable it might be.

Sorry this sounds so angry. The cause is that having stuck my neck out and said "Why are you guys moderating so much" to the mods, a free run of the thread has revealed such nonsense being posted that I'm embarrassed about having said anything. Lock away, I say!

This reminds me of EgyptAir 990. Fuel cutoff switches thrown, other pilot asks why. Then a fight for engine restart. Captain El-Habashi fought so hard it cased a split elevator. I see this investigation taking many years as the reason for the crash is investigated, analyzed and debated. I can also see one party refusing to acknowledge the facts of the crash.

Let us remember the long history of pilots fighting to save their passengers. One or perhaps both (one in a billion, I know) of these men fought with everything they had to bring everyone home alive. The eight pilots on 9/11 all fought with everything they had. The captain of Germanwings who tried to get back into the cockpit. The Ethiopian Airlines captain and FedEx crew who fought and lived to tell about it. If there are evil intentions on an aircraft, I know without doubt the crew will do anything and everything to make sure I walk off the aircraft. So let's focus on that as we wait on the final report.