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nrunning24
June 13, 2025, 14:21:00 GMT permalink Post: 11900563 |
Former Boeing Engineer, actually worked on this specific airplane prior to delivery. To me this all comes down to if the RAT was actually out. If not, lots of different factors people have already debated and likely some sort of pilot error that I'll let the pilots on this forum debate.
If the RAT did come out, then we are looking at simultaneous dual engine failure basically at V2 which is so improbable (without bird strikes or purposeful actions) that it is basically impossible. This is a 330 Min ETOPS aircraft. I saw no rudder deflection or yaw indicating 1 engine failed first and then they shut down the second one on accident. Only two realistic options for me in that case are: 1. cutoff of the engines by the pilots. Either on purpose or accidental. 2. maintenance actions by the Air India ground team that caused issues with the engine system or power generation system. 2 is the only one I haven't seen mentioned here and I say this as a no longer Boeing employee. We STRUGGLED with AI during the EIS. They were notorious for just parking airplanes and then using them as spare parts and then screaming for help when they had to go back and get the planes ready to fly again. Still think 1 is much more likely but will just throw out that 2 since there were complaints from previous flights about IFE and AC which to me speaks to issues with the power generation possibly being neglected. Subjects (links are to this post in the relevant subject page so that this post can be seen in context): Dual Engine Failure Engine Failure (All) Fuel (All) Fuel Cutoff Switches RAT (All) V2 |
nrunning24
June 13, 2025, 16:10:00 GMT permalink Post: 11900665 |
Not yet seen a response to my question about which engine parameters are recommended by the FDR and what is the sample rate.
Hopefully you might be able to answer this. Many thanks. I am a retired gas turbine engineer who worked on safety systems and assessments and assisted on a number of accident investigations (military fast jets) and would be interested to know this. Subjects (links are to this post in the relevant subject page so that this post can be seen in context): CVR FDR Parameters |
nrunning24
June 13, 2025, 16:41:00 GMT permalink Post: 11900680 |
Apologies if already discussed but I'd be interested to know
how common/unusual it is for a commercial aircraft to be "Stored for parts to be used on other 787's in the fleet" and then "Returned to Service"? These happened on 2019-01-23 and 2019-05-24 respectively according to this page.
Subjects: None |
nrunning24
June 13, 2025, 16:59:00 GMT permalink Post: 11900693 |
What I will say is that we are all so involved with our airlines and engineers definitely come home shaking their heads from airline visits sometimes. I was at my 787 airlines main offices monthly, you can tell what the operation is like quickly. AI was well known for being cheap and not wanting to do have stock of common replacement parts, and basically just used a few airplanes as their stockpiles. No one came back impressed from their visit there. Does that mean they are unsafe? No, not necessarily just that its not the most well run operation from my experience. Subjects: None |
nrunning24
June 13, 2025, 19:24:00 GMT permalink Post: 11900835 |
This guy doesn\x92t sound like a pilot so I\x92d take what he has to say about technical issues with a bucket of salt- cabin crew often get incredibly dumbed down explanations for their level of knowledge
Either way air India hasn\x92t had a terminal technical issue leading to a hull loss that I can seem to find, and it is over 60 years old. Shoddy legacy cabins has almost nothing to do with air safety and all those conflating the interiors of old air India planes with maintenance of critical items are being disingenuous at best Subjects: None |
nrunning24
July 12, 2025, 04:06:00 GMT permalink Post: 11920166 |
The switches got moved to cutoff, I dont see how anyone can take the audio from the report any other way. There are way to many ECAM warnings in this case for the pilot to know that that's what happened if there was a short or similar software failure. Add to the fact they got put back to run. Why we will find out.
Subjects (links are to this post in the relevant subject page so that this post can be seen in context): Fuel (All) Fuel Cutoff Switches |
nrunning24
July 13, 2025, 18:47:00 GMT permalink Post: 11921526 |
Former Boeing Engineer on the 787 (prob should put this in my profile at some point but newbie on the forum), but personally flown nothing bigger than a 172.
Longer I think about this the more I lean towards purposeful but not intentional action slip cutoffs by the captain. Some people have commented on sim training captains doing this to reset quicker (i wouldn't know). We know FO was flying and initial cut offs are 1 then 2, which to me says CAPT did it. But also relights were 1 then 2 which tells me CAPT also did that one most likely. Also comments around 10 seconds of delay being a long time, that's REALLY fast in my opinion especially considering, 1. this is a situation that is never trained for and 2. All sorts of lights changing, displays flickering, whole right side of the cockpit basically turning off and 3. Your really close to the ground and transitions (from takeoff to climb) lend themselves hard things to break your mind out of. That has to be a very jarring experience that needs likely a few seconds just to re-orient themselves. I'm honestly impressed they got them re-lit that fast, but assuming training with engine out and re-start procedures likely gave them a hint fuel switches from the EICAS messages. Very confident Boeing FlightOps engineers and training captains have run through this in the sim quite a few times now. Subjects (links are to this post in the relevant subject page so that this post can be seen in context): Action slip EICAS Fuel (All) Fuel Cutoff Switches Relight |
nrunning24
July 14, 2025, 15:16:00 GMT permalink Post: 11922292 |
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. Subjects (links are to this post in the relevant subject page so that this post can be seen in context): Air Worthiness Directives Fuel (All) Fuel Cutoff Switches NTSB |
nrunning24
July 14, 2025, 15:40:00 GMT permalink Post: 11922310 |
Subjects (links are to this post in the relevant subject page so that this post can be seen in context): Air Worthiness Directives |
nrunning24
July 14, 2025, 19:59:00 GMT permalink Post: 11922466 |
If you think everything is said...
Breaking News: On Jul 14th 2025 India's DGCA instructed airlines to check the fuel switches on the Boeing 787 and Boeing 737 aircraft as used by Air India Group, Indigo and Spicejet for possible disengagement of the fuel control switch locking feature according to the SAIB released by the FAA on Dec 17th 2018. The checks have to be completed by Jul 21st 2025. Source: Avherald.com Realize this is a pilots forum, and its always easier to blame the engineers (me), but I'm surprised at the amount of people grasping at (at least what I think) straws to try and make this not a case of pilot error (either intentional or unintentional). I get lots of parts frequently break and pilots do frequently see things on MEL etc. I know our partner airline engineering teams would love to see increased reliability of certain components, but the certification scrutiny of flight critical items is very intense including isolation from each other. The likelihood of two flight critical components which are isolated from each other failing instantaneously is so small its basically impossible. Especially when you consider they also turn back on 10 secs later. Last edited by T28B; 14th July 2025 at 20:57 . Reason: pulled out the bottom line with formatting Subjects (links are to this post in the relevant subject page so that this post can be seen in context): DGCA FAA Fuel (All) Fuel Cutoff Switches MEL Special Airworthiness Information Bulletin |
nrunning24
July 14, 2025, 21:01:00 GMT permalink Post: 11922500 |
I'm not surprised though it gets frustrating when folk start defaulting to the most remote possibilities instead of the more likely ones. The flight data recorder logged the fact that the switches were moved to cutoff, 1 second apart, very soon after airborne, then some seconds later moved back to run. None of that fits with any realistically conceivable mechanical failure nor automated system fault. Both of those are physical actions taken by a pilot. The first action was to shut them down, and the second action was an attempt to start them up again (tragically close to being successful). Nor does it fit with a muscle memory mistake or confusion with another switch.
Which leads to a very unpleasant possibility that many people would rather not consider, and some even refuse to consider, despite there being at least one historical precedent that I can think of (a pilot for a particular airline many years ago who had an undiagnosed mental health condition and admitted to struggling with impulsive thoughts of shutting down all 4 engines on a B747). Subjects (links are to this post in the relevant subject page so that this post can be seen in context): CVR Fuel (All) Fuel Cutoff Switches Mental Health Muscle Memory |
nrunning24
July 14, 2025, 21:23:00 GMT permalink Post: 11922512 |
I'm still not clear on something, no surprise there.
If you are the PF and you are just after rotation, and for whatever reason, the fuel control switches transition to "CUTOFF", when and how do you notice this? Presumably your hands are on the yoke and you are looking very intently out the windshield. So, to me it seems unlikely that you saw whatever happened to the switches, however they moved. Do you get a warning indication that the switches have moved? If so, then that would be what I needed to know. You got a warning and therefore you looked right at the switches. If not, do you just notice that you have lost power? If that is the case, where do you look first? I presume it would be at the engine info gauges/displays. What I'm getting at is what priority is given to looking at the fuel cutoff switches in this situation? How long until you look at those switches as the possible cause of the engine problems? Subjects (links are to this post in the relevant subject page so that this post can be seen in context): EICAS Fuel (All) Fuel Cutoff Fuel Cutoff Switches RUN/CUTOFF |
nrunning24
July 15, 2025, 15:06:00 GMT permalink Post: 11923015 |
Let stop with this nonsense. Subjects: None |
nrunning24
July 15, 2025, 15:42:00 GMT permalink Post: 11923035 |
If I'm not mistaken, someone thoughtfully up thread somewhere posted an analysis which showed that pilot suicide is really not at all common, statistically. To which I'd add that for reasons also discussed up thread, this method would be totally atypical of previously chosen methods.
That said, I'd agree pretty much entirely that the probability of two, four pole/double throw switches failing within a second of each other is vanishingly remote too. Of course, that dichotomy is why we are on the hamster wheel. Again I'm not even saying its suicide, you prob may only know if you heard the CVR and even then their could be a question. What I'm saying is anyone downplaying that as an option because it's "rare" but then goes down the path of concocting some crazy failure scenario has now come up with a situation that is orders of magnitude more improbable, just because its uncomfortable for them to think of the suicide as being a possibility. Subjects (links are to this post in the relevant subject page so that this post can be seen in context): CVR |
nrunning24
July 16, 2025, 18:15:00 GMT permalink Post: 11923900 |
SLF here with engineering background.
Regardless of what happened and why regarding the switches going to off, there is now a documented failure mode of the system that needs mitigation (?): Fuel switches off at less than XXX ft lead to unrecoverable AC. If fuel cut off during take off leads to unrecoverable at less than XXX ft or risk of error i.e. switching one vs the other, then inhibit them. I'm putting it too simplistically, but if after V1 the AC is GO and there is a range of altitude/speed that engines loss leads to unrecoverable some mitigation is needed. Subjects (links are to this post in the relevant subject page so that this post can be seen in context): Fuel (All) Fuel Cutoff Fuel Cutoff Switches V1 |
nrunning24
July 16, 2025, 18:19:00 GMT permalink Post: 11923903 |
Oh yes the classic, rotation caused these locked switches to transition to cut off but flying into a building wasn't enough force to have them do the same movement.
Subjects (links are to this post in the relevant subject page so that this post can be seen in context): Fuel (All) Fuel Cutoff Switches |
nrunning24
July 16, 2025, 18:27:00 GMT permalink Post: 11923909 |
But how many 787s switches have actually been inspected?
It was stated that Air India didn't bother to do so, as the directive or whatever it's called, was not mandatory. I'm not trying to point the finger at Air India, or suggest that these switches could be faulty, rather highlight how the industry can be seen to function. There have been numerous accidents that could have been prevented, if remedial actions had not been allowed to be deferred. Subjects: None |
nrunning24
July 16, 2025, 18:31:00 GMT permalink Post: 11923916 |
The SAIB from Boeing literally states the opposite to what you are stating.
It goes on to list models including 787-8, -9 and -10 https://ad.easa.europa.eu/blob/NM-18...SIB_NM-18-33_1 Subjects (links are to this post in the relevant subject page so that this post can be seen in context): Special Airworthiness Information Bulletin |
nrunning24
July 17, 2025, 18:52:00 GMT permalink Post: 11924570 |
Musician:
The lack of technical rigour and curiosity in this thread is disappointing. Long diatribes about switches, as if they were the only thing in the chain that could have cut off the fuel. Rumours and News, fine, but would expect a higher level of hard analysis here, especially considering the limited information presented in the initial report. It may indeed be that the tragedy was intentional, but there is no hard evidence to show that at this stage. While there are pointers suggesting that in the report, that is how if has been written, intentionally. Here, the crew are blameless until proven at fault, beyond reasonable doubt. Call that naive if you will, but science is about gathering and following the evidence, not jumping to conclusions. Subjects (links are to this post in the relevant subject page so that this post can be seen in context): Fuel (All) Fuel Cutoff Switches |
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