July 13, 2025, 11:24:00 GMT
permalink Post: 11921244
It actually doesn\x92t matter who said it for the purposes of diagnosing deliberate action, if it\x92s someone trying to cover their tracks and deflect blame onto the other person it still represents cognition that the movement of the switches was a deliberate act and will have been recorded as such.
The only known fact is that engines for some reason were shut down. The other known fact is that there is a recorded indication that the start lever command was recorded as both cutoff in short succession then followed by idle detent causing a restart attempt.
I think the key unknowns here are important.
1. Was the start lever position recorded, or only the electrical signal? My money is on an electrical signal not position, therefore the manual positioning of the start levers is not conclusively proven.
2. The bulletin for locking mechanism for the start levers has been mentioned in the preliminary report. This is a huge unknown. Did that mean that in a failure that the levers could both move into cutoff at the same time? This occurred exactly as the aircraft was rotating and increasing pitch.
3. The information from the CVR if taken at face value must not be discounted. No pilot actually confirmed conclusively seeing the other move the switch. This could have been an assumption noticing an engine failure, seeing the start levers positions in cutoff or indeed seeing the start levers moved deliberately. This is a huge critical unknown.
4. One pilot asked 'why did you cutoff' and the other responded 'I didn't'. This is not a confirmation of anything for sure. In fact it is equally a suggestion no pilot moved the switches, equally as it is saying they did. This is not conclusive. This raises an important question, was this genuine, did either pilot have any reason in their life to attempt to do this and then cover their actions? There is zero suggestion here either way, but hopefully investigators will already be looking at their backgrounds and state of affairs.
5. There is no indication who or what commanded the engines back to idle detent again. There is proof of both engines attempting to restart. I would take this as confirmation of teamwork existing on the flight deck, and this would suggest a lack of deliberate interference by either pilot. Should that have been deliberately done, so much more could have happened. It just hasn't been alluded to in the preliminary report.
My own impression is that it did not appear to be a situation of a deliberate act to crash. I say this as they appear to have both tried to save the aircraft and immediately restart the engines and recover taking some critical timely actions demonstrating competent reaction.
The timing of the commanding fuel to cutoff is critical imo. The aircraft was pitching. If an accidental command to cutoff occurred then I feel this however unlikely would have been made instead of another action. The only likely thing happening at that exact time or due 2-3 seconds after lift off was gear up. The CVR and recorded timing of engine failure in relation to that challenge and response in SOP will be key imo. Did the challenge for gear up occur before the idle detent electrical signals? Also, the focus should be on that bulletin for the locking mechanism for the start levers.
I just cannot imagine an experienced crew doing this by accident and the information just doesn't suggest a deliberate act.
My post is just to highlight huge lists of unknowns. The media appears to have made their mind up that the flight crew did this. I just highlight that is definitely not confirmed yet. We have a whole list of unknowns and conflicting communication that raises more questions than they solve.
I would urge zero conclusions be made, and RIP the crew and passengers. There are zero conclusions to what happened yet in my opinion, and I think the suggestion to relatives of the flight crew and families tragically killed that this is a known pilot deliberate action simply cannot be made at this point. We must not blame the flight crew prematurely or pretend we know what happened. I think the media should take note and back off from all the assumptions.
Last edited by Captain Biggles 101; 14th July 2025 at 09:29 .
July 13, 2025, 12:38:00 GMT
permalink Post: 11921293
I don't think it's yet time to go "there".
Remember that engine 1 had actually relit and began to recover and engine 2 had also relit.
To me it's amazing that those big engines were able to do that in the time allotted.
Why would a suicidal pilot even allow the attempt to restart within 10 seconds?
Why wouldn't he yell out the other pilot's name and ask "What are you doing?" for the CVR theater performance?
Remember that engine 1 had actually relit and began to recover and engine 2 had also relit.
To me it's amazing that those big engines were able to do that in the time allotted.
Why would a suicidal pilot even allow the attempt to restart within 10 seconds?
Why wouldn't he yell out the other pilot's name and ask "What are you doing?" for the CVR theater performance?
July 13, 2025, 12:59:00 GMT
permalink Post: 11921303
The low airspeed airflow through engine and HP RPM on Eng 1 were sufficient to allow HP RPM to increase. The longer delay between Eng 2 OFF then ON allowed HP RPM to decay more than #1, and although 'relit', I read a successful (unassisted) spool up was unlikely? (i.e. a detailed unassisted relight envelope including current HP RPM and IAS would have #1 in the envelope and #2 outside).
If we want to speculate in this area, one could ask (my best guess):
- Do the AAIB know who said "why" and who "I did not"? (Yes)
- Are they the exact words? (No) Or a 'summary'? (Yes)
- Were other words spoken by one of both pilots? (Yes)
- Do the AAIB know whether there were or were not other cockpit occupants? (Yes) Were there? (No - since to fail to mention it casts assertions on just 2 named individuals)
- Are the AAIB fairly certain of the root cause of this accident (Yes i.e. mechanical issue, unintentional HF, unlawful interference) If yes, have the AAIB deliberately sanitised this report to conceal both the root cause, and other information that would lead to uninformed speculation that does not further flight safety (Yes)
July 13, 2025, 12:59:00 GMT
permalink Post: 11921304
July 13, 2025, 13:14:00 GMT
permalink Post: 11921315
I am relieved that:
1. There is no apparent design fault in the 787, otherwise the whole global fleet would be grounded.
2. The engines relit so quickly, albeit not soon enough in this case. The relight design basically works.
Sort of worried how much this accident will make pilot life more cumbersome when our regular medical checkups reappear on our rosters.
1. There is no apparent design fault in the 787, otherwise the whole global fleet would be grounded.
2. The engines relit so quickly, albeit not soon enough in this case. The relight design basically works.
Sort of worried how much this accident will make pilot life more cumbersome when our regular medical checkups reappear on our rosters.
July 13, 2025, 14:32:00 GMT
permalink Post: 11921359
If it was an action by the captain, then claims that the plan was unlikely to succeed are disproven by the fact that it did succeed and probably with at least a few seconds to spare. He would have known that it would take a short bit of time for the FO to fully figure out that both engines had stopped and why. He would have known that shutting down for more than 10 seconds would spool down the engines far enough to make a relight either slow or unlikely and if need be, he could take further action. He also would have known that a crash into urban Ahmedabad would be catastrophic. I'm not saying his plan was perfect, but it is "reasonable" considering the stated goals and options available.
Last edited by Senior Pilot; 13th July 2025 at 17:54 . Reason: Unacceptable accusation at this time
July 13, 2025, 14:48:00 GMT
permalink Post: 11921368
At this point, I agree that intentional operation of the FCS switches is the most likely cause of the shutdown. But that doesn't mean that we know or can know what the intent of the intentional action was. And I don't think we have any compelling evidence that the intent was to crash the aircraft and kill everyone aboard.
July 13, 2025, 15:02:00 GMT
permalink Post: 11921377
With the greatest respect, I don't think any deliberate act has been proven. Allocating blame on assumptions should be avoided. People should work on facts, and then unconfirmed assumptions.
The only known fact is that engines for some reason were shut down. The other known fact is that there is a recorded indication that the start lever command was recorded as both cutoff in short succession then followed by idle detent causing a restart attempt.
I think the key unknowns here are important.
1. Was the start lever position recorded, or only the electrical signal? My money is on an electrical signal not position, therefore the manual positioning of the start levers is not conclusively proven.
2. The bulletin for locking mechanism for the start levers has been mentioned in the preliminary report. This is a huge unknown. Did that mean that in a failure that the levers could both move into cutoff at the same time? This occurred exactly as the aircraft was rotating and increasing pitch.
3. The information from the CVR if taken at face value must not be discounted. No pilot actually confirmed conclusively seeing the other move the switch. This could have been an assumption noticing an engine failure, seeing the start levers positions in cutoff or indeed seeing the start levers moved deliberately. This is a huge critical unknown.
4. One pilot asked 'why did you cutoff' and the other responded 'I didn't'. This is not a confirmation of anything for sure. In fact it is equally a suggestion nobody pilot moved the switches as it is saying they did. This is not conclusive. This raises an important question, was this genuine, did either pilot have any reason in their life to attempt to do this and then cover their actions? There is zero suggestion here either way, but hopefully investigators will already be looking at their backgrounds and state of affairs.
5. There is no indication who or what commanded the engines back to idle detent again. There is proof of both engines attempting to restart. I would take this as confirmation of teamwork existing on the flight deck, and this would suggest a lack of deliberate interference by either pilot. Should that have been deliberately done, so much more could have happened. It just hasn't been alluded to in the preliminary report.
My own impression is that it did not appear to be a situation of a deliberate act to crash. I say this as they appear to have both tried to save the aircraft and immediately restart the engines and recover taking some critical timely actions demonstrating competent reaction.
The timing of the commanding fuel to cutoff os critical imo. The aircraft was pitching. If an accidental command to cutoff occurred then I feel this however unlikely would have been made instead of another action. The only likely thing happening at that exact time or due 2-3 seconds after lift off was gear up. The CVR and recorded timing of engine failure in relation to that challenge and response in SOP will be key imo. Did the challenge for gear up occur before the idle detent electrical signals? Also, the focus should be on that bulletin for the locking mechanism for the start levers.
I just cannot imagine an experienced crew doing this by accident and the information just doesn't suggest a deliberate act.
My post is just to highlight huge lists of unknowns. The media appears to have made their mind up that the flight crew did this. I just highlight that is definitely not confirmed yet. We have a whole list of unknowns and conflicting communication that raises more questions than they solve.
I would urge zero conclusions be made, and RIP the crew and passengers. There are zero conclusions to what happened yet in my opinion, and I think the suggestion to relatives of the flight crew and families tragically killed that this is a known pilot deliberate action simply cannot be made at this point. We must not blame the flight crew prematurely or pretend we know what happened. I think the media should take note and back off from all the assumptions.
The only known fact is that engines for some reason were shut down. The other known fact is that there is a recorded indication that the start lever command was recorded as both cutoff in short succession then followed by idle detent causing a restart attempt.
I think the key unknowns here are important.
1. Was the start lever position recorded, or only the electrical signal? My money is on an electrical signal not position, therefore the manual positioning of the start levers is not conclusively proven.
2. The bulletin for locking mechanism for the start levers has been mentioned in the preliminary report. This is a huge unknown. Did that mean that in a failure that the levers could both move into cutoff at the same time? This occurred exactly as the aircraft was rotating and increasing pitch.
3. The information from the CVR if taken at face value must not be discounted. No pilot actually confirmed conclusively seeing the other move the switch. This could have been an assumption noticing an engine failure, seeing the start levers positions in cutoff or indeed seeing the start levers moved deliberately. This is a huge critical unknown.
4. One pilot asked 'why did you cutoff' and the other responded 'I didn't'. This is not a confirmation of anything for sure. In fact it is equally a suggestion nobody pilot moved the switches as it is saying they did. This is not conclusive. This raises an important question, was this genuine, did either pilot have any reason in their life to attempt to do this and then cover their actions? There is zero suggestion here either way, but hopefully investigators will already be looking at their backgrounds and state of affairs.
5. There is no indication who or what commanded the engines back to idle detent again. There is proof of both engines attempting to restart. I would take this as confirmation of teamwork existing on the flight deck, and this would suggest a lack of deliberate interference by either pilot. Should that have been deliberately done, so much more could have happened. It just hasn't been alluded to in the preliminary report.
My own impression is that it did not appear to be a situation of a deliberate act to crash. I say this as they appear to have both tried to save the aircraft and immediately restart the engines and recover taking some critical timely actions demonstrating competent reaction.
The timing of the commanding fuel to cutoff os critical imo. The aircraft was pitching. If an accidental command to cutoff occurred then I feel this however unlikely would have been made instead of another action. The only likely thing happening at that exact time or due 2-3 seconds after lift off was gear up. The CVR and recorded timing of engine failure in relation to that challenge and response in SOP will be key imo. Did the challenge for gear up occur before the idle detent electrical signals? Also, the focus should be on that bulletin for the locking mechanism for the start levers.
I just cannot imagine an experienced crew doing this by accident and the information just doesn't suggest a deliberate act.
My post is just to highlight huge lists of unknowns. The media appears to have made their mind up that the flight crew did this. I just highlight that is definitely not confirmed yet. We have a whole list of unknowns and conflicting communication that raises more questions than they solve.
I would urge zero conclusions be made, and RIP the crew and passengers. There are zero conclusions to what happened yet in my opinion, and I think the suggestion to relatives of the flight crew and families tragically killed that this is a known pilot deliberate action simply cannot be made at this point. We must not blame the flight crew prematurely or pretend we know what happened. I think the media should take note and back off from all the assumptions.
Kudos to the crew for trying to re-light the engines so quickly.
My 10 cents is on the switches and there is not a aireworthiness directive out there for nothing.
July 13, 2025, 15:42:00 GMT
permalink Post: 11921402
2. If you can recall: were they able to relight the engine that went to zero thrust?
(Being at cruise altitude they had time and altitude to work with, which AI 171 crew didn't).
3. Thank you for sharing that related event.
July 13, 2025, 16:06:00 GMT
permalink Post: 11921408
If the intent was suicide, in order to make the situation unrecoverable, pulling both fire handles would be the next item to ensure the engines would not restart in the time available, therefore if only the run/cutoff switches were moved to cut off, then the situation was not foreseeably unrecoverable and can only questionably be construed as a suicide.
July 13, 2025, 17:37:00 GMT
permalink Post: 11921474
A bit of psycology. If one were intent on crashing the plane and did switch to cut off, they would most likely fight like hell to keep them off.
Kudos to the crew for trying to re-light the engines so quickly.
My 10 cents is on the switches and there is not a aireworthiness directive out there for nothing.
Kudos to the crew for trying to re-light the engines so quickly.
My 10 cents is on the switches and there is not a aireworthiness directive out there for nothing.
edit: Sorry, didn't see Andy S post.....
July 13, 2025, 17:45:00 GMT
permalink Post: 11921481
The event shows that it's really imperative to relight the engines as quickly as possible.
The preliminary report says it took about 5 seconds for the engines to spool down to idle. 14 CFR \xa7 33.73 - Power or thrust response requires a jet engine to reach 95% thrust from stabilized flight idle in not over 5 seconds. So with a sufficiently quick reaction, flipping the switches back after 5 seconds, they could've been back in business by the time they actually flipped the switches back.
So it's not "flip the switches 3 seconds after liftoff and you're unrecoverable"; to be unrecoverable, there must also be sufficient time for the engines to spool down enough.
Don't ask, "why did you cut the engines", flip them back on. Go for the E in PACE.
The preliminary report says it took about 5 seconds for the engines to spool down to idle. 14 CFR \xa7 33.73 - Power or thrust response requires a jet engine to reach 95% thrust from stabilized flight idle in not over 5 seconds. So with a sufficiently quick reaction, flipping the switches back after 5 seconds, they could've been back in business by the time they actually flipped the switches back.
So it's not "flip the switches 3 seconds after liftoff and you're unrecoverable"; to be unrecoverable, there must also be sufficient time for the engines to spool down enough.
Don't ask, "why did you cut the engines", flip them back on. Go for the E in PACE.
July 13, 2025, 17:54:00 GMT
permalink Post: 11921488
The event shows that it's really imperative to relight the engines as quickly as possible.
The preliminary report says it took about 5 seconds for the engines to spool down to idle. 14 CFR \xa7 33.73 - Power or thrust response requires a jet engine to reach 95% thrust from stabilized flight idle in not over 5 seconds. So with a sufficiently quick reaction, flipping the switches back after 5 seconds, they could've been back in business by the time they actually flipped the switches back.
So it's not "flip the switches 3 seconds after liftoff and you're unrecoverable"; to be unrecoverable, there must also be sufficient time for the engines to spool down enough.
Don't ask, "why did you cut the engines", flip them back on. Go for the E in PACE.
The preliminary report says it took about 5 seconds for the engines to spool down to idle. 14 CFR \xa7 33.73 - Power or thrust response requires a jet engine to reach 95% thrust from stabilized flight idle in not over 5 seconds. So with a sufficiently quick reaction, flipping the switches back after 5 seconds, they could've been back in business by the time they actually flipped the switches back.
So it's not "flip the switches 3 seconds after liftoff and you're unrecoverable"; to be unrecoverable, there must also be sufficient time for the engines to spool down enough.
Don't ask, "why did you cut the engines", flip them back on. Go for the E in PACE.
It's possible from the timeline in the report that this statement was made at the same time (or even after) they were moved back to RUN. The report is ambiguous on this unfortunately...!
Re: spool down to idle, that is interesting and passed me by - the report certainly does imply it took 5 seconds, which is at odds at an earlier post from (I believe) tdracer , who said this would take 1, maximum 2, seconds.
However when I read it again, it's again ambiguous - the 5 seconds is when the RAT started supplying power, but this isn't clear and unequivocal that engine went below idle at the same time in the wording, although definitely heavily implied.
July 13, 2025, 18:46:00 GMT
permalink Post: 11921525
If the intent was suicide, in order to make the situation unrecoverable, pulling both fire handles would be the next item to ensure the engines would not restart in the time available, therefore if only the run/cutoff switches were moved to cut off, then the situation was not foreseeably unrecoverable and can only questionably be construed as a suicide.
The evidence shows 2-3 extraordinary possibilities all full of caveats, and since nothing else has been issued it seems incredibly unlikely that anyone involved in the investigation is concerned that there is a chance of accidental cutoff from the switch, electronics, software or cockpit design.
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.
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.
July 13, 2025, 19:37:00 GMT
permalink Post: 11921569
Thanks to you both.
So this brings me back to my original observation (and that of another poster) - it would appear that there was a time period of at least 2 seconds, and potentially longer depending upon RAT electrical power, where the aircraft lost some (?) or all (?) electrical power, which hasn't really been discussed.
This would definitely contribute to recovery challenges (albeit slightly tangential to root cause discussion).
(And, strangely, ADS data appeared to continue during the period this would have occurred)
So this brings me back to my original observation (and that of another poster) - it would appear that there was a time period of at least 2 seconds, and potentially longer depending upon RAT electrical power, where the aircraft lost some (?) or all (?) electrical power, which hasn't really been discussed.
This would definitely contribute to recovery challenges (albeit slightly tangential to root cause discussion).
(And, strangely, ADS data appeared to continue during the period this would have occurred)
Without the APU, would there have been sufficient power to restart even one engine, never mind two?
Could this be why the delay between the first and second switches being moved to RUN?
Does it also mean that in reality the 10 seconds between OFF and RUN is immaterial as there was insufficient electrical power to start the engines anyway?
July 13, 2025, 19:56:00 GMT
permalink Post: 11921588
It was working as per the conditions absolutely, but those conditions meant it wasn't available immediately.
I hardly think that the single sole relevant learning from an event such as this, and hence the sole discussion point, is around the trigger of the event. Yes, very relevant, but plenty of other areas to understand further as well (for example how a dual engine failure at such altitude could be adjusted in future process). If you aren't interested in that discussion that's ok of course, but it doesn't make it irrelevant.
July 13, 2025, 20:03:00 GMT
permalink Post: 11921594
Because it wouldnt have been immediately available to support engine restart and/or other electrical functions, as it didn't open until around 13 seconds after cutoff event. It's relevant in so much of how it may (or may not) have affected recovery efforts.
It was working as per the conditions absolutely, but those conditions meant it wasn't available immediately.
It was working as per the conditions absolutely, but those conditions meant it wasn't available immediately.
July 13, 2025, 20:14:00 GMT
permalink Post: 11921600
If it was an action by the captain, then claims that the plan was unlikely to succeed are disproven by the fact that it did succeed and probably with at least a few seconds to spare. He would have known that it would take a short bit of time for the FO to fully figure out that both engines had stopped and why. He would have known that shutting down for more than 10 seconds would spool down the engines far enough to make a relight either slow or unlikely and if need be, he could take further action. He also would have known that a crash into urban Ahmedabad would be catastrophic. I'm not saying his plan was perfect, but it is "reasonable" considering the stated goals and options available.
July 13, 2025, 20:21:00 GMT
permalink Post: 11921608
Some human in that flight deck moved both fuel switches to cutoff, physically moved them, one after the other. Another human, possibly either human in that flight deck then questioned verbally why they did that. This is factual and proven evidence as per the official report. Why are we not focusing on the who and why!?
Not sure how much more evidence you need to start a discussion.
We as operators are trying to put ourselves in that situation and describe likely outcomes based on present experiences. The most likely event is the PM orchestrating this, the Captain in this case. This however is up for debate\x85 the debate we should be having\x85 not APU doors.
Not sure how much more evidence you need to start a discussion.
We as operators are trying to put ourselves in that situation and describe likely outcomes based on present experiences. The most likely event is the PM orchestrating this, the Captain in this case. This however is up for debate\x85 the debate we should be having\x85 not APU doors.
I certainly don't need more evidence than we have for discussion. I just think a lot more evidence is necessary to conclude that either crew member on that flight deliberately killed the engines intending to crash the jet and, for some reason, accused the other of doing so. Indeed, I don't think we have any actual evidence for that. We simply have a set of circumstances that make that one of only a few possibilities we can reasonably imagine. Discussing it as a possibility is reasonable (although I don't think we can get anywhere on that path without evidence), but claiming that possibility as the one, the truth, what really happened, is not reasonable, not justified by the available evidence. And making unjustified claims that amount to accusing a pilot of mass murder, in a forum that citizens and journalists from around the world always turn to for information in the wake of a major airliner crash, seems like a very bad idea to me.