2025-06-18T07:26:00
permalink Post: 11904987
There has been a lot of discussion of the possibility that the crew shut down the wrong engine or misidentified some other problem as an engine failure, usually followed by an assertion that nobody would touch the engines before x feet. PPRuNe's own survey, at the top of this very subforum, found a really high base rate of wrong engine incidents:
Also, on the point about sitting on your hands to 400/1000 feet AAL, someone who has already deviated from a standard operating procedure is more likely to go on to make another mistake; that is why the procedure existed in the first place.
As a memo item, here are the survey results:
Q1. Have you ever shut off the wrong engine in the sim?
Yes: 5.4% +0.9%
No: 94.6% -0.9%
Q2. Have you ever ALMOST shut off the wrong engine in the sim?
Yes: 26% -1.0%
No: 74% +1.0%
Q3. Have you ever witnessed a colleague shut off the wrong engine in the sim?
Yes: 16% +1.0%
No: 84% -1.0%
Q4. Have you ever witnessed a colleague ALMOST shut off the wrong engine in the sim?
Yes: 45% +2.0%
No: 55% -2.0%
Link to original post
Senior Pilot
- 31 per cent of the PPRuNe Population reported either having a wrong-engine incident or a close call
- 61 per cent reported witnessing one
Also, on the point about sitting on your hands to 400/1000 feet AAL, someone who has already deviated from a standard operating procedure is more likely to go on to make another mistake; that is why the procedure existed in the first place.
As a memo item, here are the survey results:
Q1. Have you ever shut off the wrong engine in the sim?
Yes: 5.4% +0.9%
No: 94.6% -0.9%
Q2. Have you ever ALMOST shut off the wrong engine in the sim?
Yes: 26% -1.0%
No: 74% +1.0%
Q3. Have you ever witnessed a colleague shut off the wrong engine in the sim?
Yes: 16% +1.0%
No: 84% -1.0%
Q4. Have you ever witnessed a colleague ALMOST shut off the wrong engine in the sim?
Yes: 45% +2.0%
No: 55% -2.0%
Link to original post
Senior Pilot
Last edited by Senior Pilot; 18th Jun 2025 at 07:35 . Reason: Add link
5 users liked this post.
2025-06-18T15:00:00
permalink Post: 11905313
There has been a lot of discussion of the possibility that the crew shut down the wrong engine or misidentified some other problem as an engine failure, usually followed by an assertion that nobody would touch the engines before x feet. PPRuNe's own survey, at the top of this very subforum, found a really high base rate of wrong engine incidents:
Also, on the point about sitting on your hands to 400/1000 feet AAL, someone who has already deviated from a standard operating procedure is more likely to go on to make another mistake; that is why the procedure existed in the first place.
As a memo item, here are the survey results:
Q1. Have you ever shut off the wrong engine in the sim?
Yes: 5.4% +0.9%
No: 94.6% -0.9%
Q2. Have you ever ALMOST shut off the wrong engine in the sim?
Yes: 26% -1.0%
No: 74% +1.0%
Q3. Have you ever witnessed a colleague shut off the wrong engine in the sim?
Yes: 16% +1.0%
No: 84% -1.0%
Q4. Have you ever witnessed a colleague ALMOST shut off the wrong engine in the sim?
Yes: 45% +2.0%
No: 55% -2.0%
Link to original post
Senior Pilot
- 31 per cent of the PPRuNe Population reported either having a wrong-engine incident or a close call
- 61 per cent reported witnessing one
Also, on the point about sitting on your hands to 400/1000 feet AAL, someone who has already deviated from a standard operating procedure is more likely to go on to make another mistake; that is why the procedure existed in the first place.
As a memo item, here are the survey results:
Q1. Have you ever shut off the wrong engine in the sim?
Yes: 5.4% +0.9%
No: 94.6% -0.9%
Q2. Have you ever ALMOST shut off the wrong engine in the sim?
Yes: 26% -1.0%
No: 74% +1.0%
Q3. Have you ever witnessed a colleague shut off the wrong engine in the sim?
Yes: 16% +1.0%
No: 84% -1.0%
Q4. Have you ever witnessed a colleague ALMOST shut off the wrong engine in the sim?
Yes: 45% +2.0%
No: 55% -2.0%
Link to original post
Senior Pilot
2 users liked this post.
2025-06-19T14:51:00
permalink Post: 11906087
OK, I promised some
informed speculation
when I got back, so here goes:
Disclaimer: never worked the 787, so my detailed knowledge is a bit lacking.
First off, this is perplexing - especially if the RAT was deployed. There is no 'simple' explanation that I can come up with.
GEnx-1B engines have been exceptionally reliable, and the GE carbon composite fan blades are very robust and resistant to bird strike damage (about 15 years after the GE90 entry into service, I remember a GE boast that no GE90 (carbon composite) fan blades had needed to be scrapped due to damage (birdstrike, FOD, etc. - now that was roughly another 15 years ago, so is probably no longer true, but it shows just how robust the carbon composite blades are - far better than the more conventional titanium fan blades).
Not saying it wasn't somehow birdstrike related, just that is very unlikely (then again, all the other explanations I can come up with are also very unlikely
).
Using improper temp when calculating TO performance - after some near misses, Boeing added logic that cross-compares multiple total temp probes - aircraft TAT (I think the 787 uses a single, dual element probe for aircraft TAT, but stand to be corrected) and the temp measured by the engine inlet probes - and puts up a message if they disagree by more than a few degree tolerance - so very, very unlikely.
N1 power setting is somewhat less prone to measurement and power setting errors than EPR (N1 is a much simpler measurement than Rolls EPR) - although even with EPR, problems on both engines at the same time is almost unheard of.
The Auto Thrust (autothrottle) function 'falls asleep' at 60 knots - and doesn't unlock until one of several things happens - 250 knots, a set altitude AGL is exceeded (I'm thinking 3,000 ft. but the memory is fuzzy), thrust levers are moved more than a couple of degrees, or the mode select is changed (memory says that last one is inhibited below 400 ft. AGL). So an Auto Thrust malfunction is also extremely unlikely. Further, a premature thrust lever retard would not explain a RAT deployment.
TO does seem to be very late in the takeoff role - even with a big derate, you still must accelerate fast enough to reach V1 with enough runway to stop - so there is still considerable margin if both engines are operating normally. That makes me wonder if they had the correct TO power setting - but I'm at a loss to explain how they could have fouled that up with all the protections that the 787 puts on that.
If one engine did fail after V1, it's conceivable that they shut down the wrong engine - but since this happened literally seconds after takeoff, it begs the question why they would be in a big hurry to shut down the engine. Short of an engine fire, there is nothing about an engine failure that requires quick action to shut it down - no evidence of an engine fire, and even with an engine fire, you normally have minutes to take action - not seconds.
The one thing I keep thinking about is someone placing both fuel switches to cutoff immediately after TO. Yes, it's happened before (twice - 767s in the early 1980s), but the root causes of that mistake are understood and have been corrected. Hard to explain how it could happen ( unless, God forbid, it was intentional ).
Disclaimer: never worked the 787, so my detailed knowledge is a bit lacking.
First off, this is perplexing - especially if the RAT was deployed. There is no 'simple' explanation that I can come up with.
GEnx-1B engines have been exceptionally reliable, and the GE carbon composite fan blades are very robust and resistant to bird strike damage (about 15 years after the GE90 entry into service, I remember a GE boast that no GE90 (carbon composite) fan blades had needed to be scrapped due to damage (birdstrike, FOD, etc. - now that was roughly another 15 years ago, so is probably no longer true, but it shows just how robust the carbon composite blades are - far better than the more conventional titanium fan blades).
Not saying it wasn't somehow birdstrike related, just that is very unlikely (then again, all the other explanations I can come up with are also very unlikely
).
Using improper temp when calculating TO performance - after some near misses, Boeing added logic that cross-compares multiple total temp probes - aircraft TAT (I think the 787 uses a single, dual element probe for aircraft TAT, but stand to be corrected) and the temp measured by the engine inlet probes - and puts up a message if they disagree by more than a few degree tolerance - so very, very unlikely.
N1 power setting is somewhat less prone to measurement and power setting errors than EPR (N1 is a much simpler measurement than Rolls EPR) - although even with EPR, problems on both engines at the same time is almost unheard of.
The Auto Thrust (autothrottle) function 'falls asleep' at 60 knots - and doesn't unlock until one of several things happens - 250 knots, a set altitude AGL is exceeded (I'm thinking 3,000 ft. but the memory is fuzzy), thrust levers are moved more than a couple of degrees, or the mode select is changed (memory says that last one is inhibited below 400 ft. AGL). So an Auto Thrust malfunction is also extremely unlikely. Further, a premature thrust lever retard would not explain a RAT deployment.
TO does seem to be very late in the takeoff role - even with a big derate, you still must accelerate fast enough to reach V1 with enough runway to stop - so there is still considerable margin if both engines are operating normally. That makes me wonder if they had the correct TO power setting - but I'm at a loss to explain how they could have fouled that up with all the protections that the 787 puts on that.
If one engine did fail after V1, it's conceivable that they shut down the wrong engine - but since this happened literally seconds after takeoff, it begs the question why they would be in a big hurry to shut down the engine. Short of an engine fire, there is nothing about an engine failure that requires quick action to shut it down - no evidence of an engine fire, and even with an engine fire, you normally have minutes to take action - not seconds.
The one thing I keep thinking about is someone placing both fuel switches to cutoff immediately after TO. Yes, it's happened before (twice - 767s in the early 1980s), but the root causes of that mistake are understood and have been corrected. Hard to explain how it could happen ( unless, God forbid, it was intentional ).
3 users liked this post.
2025-06-19T19:05:00
permalink Post: 11906278
There were simultaneous engine failures, but those were due to massive birdstrikes (
US1549
) or due to epidemic engine failures on Il-62s of various versions (like
LOT 007
or
LOT 5055
).
Fuel related total engine failures like Aeroflot 366 or Air Transat 236 at least had the decency to have the engines starve one after another as the fuel in the individual tanks depleted.
But all those are probably highly irrelevant when considering the Air India accident. An engine disintegration or a heavy birdstrike would have been visible on the videos, a sizeable bird would have left some remains. And gradual fuel starvation would have shown some yaw.
As much as I despise the thought, the issue that got AI171 must have come from within the aircraft, although this most decidedly does not infer any wrongdoing by any crewmember.
Fuel related total engine failures like Aeroflot 366 or Air Transat 236 at least had the decency to have the engines starve one after another as the fuel in the individual tanks depleted.
But all those are probably highly irrelevant when considering the Air India accident. An engine disintegration or a heavy birdstrike would have been visible on the videos, a sizeable bird would have left some remains. And gradual fuel starvation would have shown some yaw.
As much as I despise the thought, the issue that got AI171 must have come from within the aircraft, although this most decidedly does not infer any wrongdoing by any crewmember.
- GoAir320 at Delhi
- Transasia AT72 at Taipei
- Alitalia A332 at Seoul
- SA Airlink JS41 at Durban
Not saying it happened here!
2025-06-19T23:26:00
permalink Post: 11906480
Summary of main theories
DISCLAIMER: Poster (a) is one of the (apparently quite numerous) lawyers following this thread; (b) a long-time forum lurker and aviation enthusiast who loves studying FCOMs for fun (to each his own, I guess); (c) has followed and read this thread from the start.
What I cannot do is add new theories or uncover any new facts the actual experts have not already thought of. However, since summarizing and structuring information is one thing lawyers tend to regularly do (and sometimes even do well), here is my attempt at a useful contribution to this thread: an attempt to summarize the main theories discussed here since day one (which I think hasn't been done for quite some time) in the hope that a birds-eye view will be helpful to those who have not read everything since the beginning or might even trigger some new flash of inspiration for someone more knowledgable than me. I have focused on the cons since there does not seem to be enough evidence to come to any positive conclusion.
I shall try to be concise and to refrain from personal evaluations of my own. Of course, no disrespect whatsoever is intended towards all those who have contributed to this thread and to the individual theories, one or combinations of which may turn out to have led to this tragic outcome. That arguments can be made against every single theory that has been propagated seems to be the result of the highly improbable and unusual nature of this deplorable event and certainly not due to any lack of knowledge or reasoning skills in this forum.
DEAR MODS: If I have distorted anything or if, meaning well, should have achieved the opposite \x96 I guess you know where the delete button is\x85
Anyway, here goes:
A. Misconfiguration or wrong takeoff data
Widely refuted, since
Still brought up from time to time. However, widely disregarded due to
It should be pointed out that the question of "RAT in or out" was for a while the most contentious in this thread.
C. Low-altitude capture
Still argued, even if refuted by many since
Various possible reasons for this have been discussed:
I. Bird strike/FOD
Unclear which maintenance measures could possibly have been performed that would have resulted in simultaneous loss of both engines. No apparent relationships between malfunctions reported by previous passengers and essential systems.
IV. Large-scale electrical fault (e.g. due to water in E&E bay)
The engines will continue to run if electrical power is lost. FADECs are powered independently.
V. Shutdown of engines by TCMA
A parallel is drawn to the ANA incident. However, this would require not only a fault in the air/ground logic but also a sensed discrepancy between T/L position (not necessarily idle) and thrust output on both engines simultaneously.
VI. (Inadvertent) shutdown by flight crew
What I cannot do is add new theories or uncover any new facts the actual experts have not already thought of. However, since summarizing and structuring information is one thing lawyers tend to regularly do (and sometimes even do well), here is my attempt at a useful contribution to this thread: an attempt to summarize the main theories discussed here since day one (which I think hasn't been done for quite some time) in the hope that a birds-eye view will be helpful to those who have not read everything since the beginning or might even trigger some new flash of inspiration for someone more knowledgable than me. I have focused on the cons since there does not seem to be enough evidence to come to any positive conclusion.
I shall try to be concise and to refrain from personal evaluations of my own. Of course, no disrespect whatsoever is intended towards all those who have contributed to this thread and to the individual theories, one or combinations of which may turn out to have led to this tragic outcome. That arguments can be made against every single theory that has been propagated seems to be the result of the highly improbable and unusual nature of this deplorable event and certainly not due to any lack of knowledge or reasoning skills in this forum.
DEAR MODS: If I have distorted anything or if, meaning well, should have achieved the opposite \x96 I guess you know where the delete button is\x85
Anyway, here goes:
A. Misconfiguration or wrong takeoff data
Widely refuted, since
- rotation, takeoff and initial climb seem normal;
- likely extreme errors would have been required to have such tragic effect (the fuel tanks should have been only about half full, so not close to MTOW);
- there is strong evidence that at least some flaps were extended for takeoff (post-crash photo, perhaps also visible in video from behind)
Still brought up from time to time. However, widely disregarded due to
- the fact that with two working engines an inadvertent flap retraction should easily be recoverable, even with gear down;
- strong indications that hydraulic and electric power were lost (audible/visible indications of RAT extension, survivor statement, lack of engine noise, position of MLG bogies).
It should be pointed out that the question of "RAT in or out" was for a while the most contentious in this thread.
C. Low-altitude capture
Still argued, even if refuted by many since
- inconsistent with apparent loss of hydraulic/electric power;
- PF would have been flying manually (however, A/T reaction would have been unexpected for the PF);
- should have been recoverable (unless one assumes that the crew (a) remained unaware of the changed FMA annunciations although alerted by the unexpected FD commands; and (b) was so startled that an A/T thrust reduction was not noticed and corrected, even though the PF was apparently sufficiently alert not to follow the FD commands).
Various possible reasons for this have been discussed:
I. Bird strike/FOD
- Would have to have occurred simultaneously due to lack of rudder/aileron input indicating symmetric thrust.
- No remains/traces on runway, no visual indications (flocks of birds, flames, structural engine damage).
1. Loss of electric fuel pumps
Suction feed would have provided sufficient fuel pressure.
2. Fuel contamination
No other aircraft affected, no measures taken at airport. Simultaneous flameout due to contaminated fuel very unlikely.
3. Vapour lock
Unlikely to occur in this scenario. Even if (momentarily) no sufficient fuel pressure from the center tank, the engines would have been fed by the wing tanks.
III. Improper maintenance
Unclear which maintenance measures could possibly have been performed that would have resulted in simultaneous loss of both engines. No apparent relationships between malfunctions reported by previous passengers and essential systems.
IV. Large-scale electrical fault (e.g. due to water in E&E bay)
The engines will continue to run if electrical power is lost. FADECs are powered independently.
V. Shutdown of engines by TCMA
A parallel is drawn to the ANA incident. However, this would require not only a fault in the air/ground logic but also a sensed discrepancy between T/L position (not necessarily idle) and thrust output on both engines simultaneously.
VI. (Inadvertent) shutdown by flight crew
1. Spontaneous execution of memory items (fuel control switches OFF, then ON; deploy RAT) due to assumed engine malfunction
In contrast to mistakenly shutting down the wrong engine after having correctly diagnosed the problem as per SOP, this would require not only a simple error in execution but a counter-intuitive unilateral action immediately after takeoff against basic principles of SOP or CRM.
2. No indications whatsoever of an intentional shutdown for nefarious reasons
(Would also be inconsistent with the content of the alleged mayday call.)
VII.
Malfunction/mishandling of the fuel cutoff switches (most recent)
1.
Wear or improper operation of the switches, so that they do not lock but can shift back into the OFF position.
Argued to be impossible due to robust switch design, preventing switch release in any other than a locked position.
Actuation of the switches by an item placed before them which was pushed onto the switches by retarding thrust levers seems equally unlikely due to force required to pull the switches out of the locked position.
Actuation of the switches by an item placed before them which was pushed onto the switches by retarding thrust levers seems equally unlikely due to force required to pull the switches out of the locked position.
2.
Spilled drink leading to short in the wiring
Hardly conceivable that before takeoff open liquid containers would be placed anywhere where they could spill onto the pedestal.
29 users liked this post.
2025-06-20T04:57:00
permalink Post: 11906594
The Indian Express is carrying a story (
https://indianexpress.com/article/ci...lues-10077117/
) that includes the following:"Investigators probing the June 12
crash of Air India flight AI-171 from Ahmedabad to London Gatwick
are taking a close look at a February 2020 incident in Gatwick, involving an Airbus A321, in which both engines malfunctioned immediately after takeoff. It led to a Mayday call before the aircraft returned to Gatwick 11 minutes later after a turnaround." ...
..."it was \x93clear from visual observation and wreckage\x94 that the flight suffered a power failure." ...
..."The black boxes and the DVR have been recovered but the officer said that the devices were damaged and file extraction would \x93be a complicated process\x94." ...
... "We will check the technical logs to see if any of the engineering teams or pilots of the previous flight left comments on the performance of both engines"
Assuming there is some credence to the article, dual engine failure due to water contamination is the leading theory. It certainly fits much of the speculation in this thread. It may be that the flight data was not captured and much more reliance will be on forensic examination of the CCTV footage and the wreckage. Those waiting for the flight data to be published may be disappointed.
If the original CCTV footage was made available, together with a detailed survey map of the airport, it will be possible to accurately estimate the takeoff speed and altitude during all the critical periods. My guess is thrust was reduced or lost very early and perhaps before the aircraft left the tarmac. Then shortly after becoming airborne, power was lost resulting in the deployment of the RAT. It is doubtful that the pilots shut down the engines or the wrong engine. Likewise flap/slat misconfiguration is unlikely.
..."it was \x93clear from visual observation and wreckage\x94 that the flight suffered a power failure." ...
..."The black boxes and the DVR have been recovered but the officer said that the devices were damaged and file extraction would \x93be a complicated process\x94." ...
... "We will check the technical logs to see if any of the engineering teams or pilots of the previous flight left comments on the performance of both engines"
Assuming there is some credence to the article, dual engine failure due to water contamination is the leading theory. It certainly fits much of the speculation in this thread. It may be that the flight data was not captured and much more reliance will be on forensic examination of the CCTV footage and the wreckage. Those waiting for the flight data to be published may be disappointed.
If the original CCTV footage was made available, together with a detailed survey map of the airport, it will be possible to accurately estimate the takeoff speed and altitude during all the critical periods. My guess is thrust was reduced or lost very early and perhaps before the aircraft left the tarmac. Then shortly after becoming airborne, power was lost resulting in the deployment of the RAT. It is doubtful that the pilots shut down the engines or the wrong engine. Likewise flap/slat misconfiguration is unlikely.
1 user liked this post.
2025-06-20T08:36:00
permalink Post: 11906715
The Indian Express is carrying a story (
https://indianexpress.com/article/ci...lues-10077117/
) that includes the following:"Investigators probing the June 12
crash of Air India flight AI-171 from Ahmedabad to London Gatwick
are taking a close look at a February 2020 incident in Gatwick, involving an Airbus A321, in which both engines malfunctioned immediately after takeoff. It led to a Mayday call before the aircraft returned to Gatwick 11 minutes later after a turnaround." ...
..."it was “clear from visual observation and wreckage” that the flight suffered a power failure." ...
..."The black boxes and the DVR have been recovered but the officer said that the devices were damaged and file extraction would “be a complicated process”." ...
... "We will check the technical logs to see if any of the engineering teams or pilots of the previous flight left comments on the performance of both engines"
Assuming there is some credence to the article, dual engine failure due to water contamination is the leading theory. It certainly fits much of the speculation in this thread. It may be that the flight data was not captured and much more reliance will be on forensic examination of the CCTV footage and the wreckage. Those waiting for the flight data to be published may be disappointed.
If the original CCTV footage was made available, together with a detailed survey map of the airport, it will be possible to accurately estimate the takeoff speed and altitude during all the critical periods. My guess is thrust was reduced or lost very early and perhaps before the aircraft left the tarmac. Then shortly after becoming airborne, power was lost resulting in the deployment of the RAT. It is doubtful that the pilots shut down the engines or the wrong engine. Likewise flap/slat misconfiguration is unlikely.
..."it was “clear from visual observation and wreckage” that the flight suffered a power failure." ...
..."The black boxes and the DVR have been recovered but the officer said that the devices were damaged and file extraction would “be a complicated process”." ...
... "We will check the technical logs to see if any of the engineering teams or pilots of the previous flight left comments on the performance of both engines"
Assuming there is some credence to the article, dual engine failure due to water contamination is the leading theory. It certainly fits much of the speculation in this thread. It may be that the flight data was not captured and much more reliance will be on forensic examination of the CCTV footage and the wreckage. Those waiting for the flight data to be published may be disappointed.
If the original CCTV footage was made available, together with a detailed survey map of the airport, it will be possible to accurately estimate the takeoff speed and altitude during all the critical periods. My guess is thrust was reduced or lost very early and perhaps before the aircraft left the tarmac. Then shortly after becoming airborne, power was lost resulting in the deployment of the RAT. It is doubtful that the pilots shut down the engines or the wrong engine. Likewise flap/slat misconfiguration is unlikely.
https://www.gov.uk/aaib-reports/airc...-february-2020
Last edited by Senior Pilot; 20th Jun 2025 at 08:51 . Reason: Remove oversized image and sort out hyperlink
1 user liked this post.
2025-06-20T13:30:00
permalink Post: 11906974
Shutting down the wrong engine below 400 AGL is extremely rare. So rare in fact that I believe it has not happened in a jet transport class aircraft.
1 user liked this post.
2025-06-20T15:41:00
permalink Post: 11907068
Sailvi767 wrote
It happened to a BAC 111 taking off from Linate Milan in 1969 when the wrong engine was shut down after a surge on takeoff. The plane never got above 250 feet and landed in a snow covered field gear up. The wrong engine identification was initiated by a Captain on the jumpseat!
https://aerossurance.com/safety-mana...human-factors/
Shutting down the wrong engine below 400 AGL is extremely rare. So rare in fact that I believe it has not happened in a jet transport class aircraft.
https://aerossurance.com/safety-mana...human-factors/
3 users liked this post.
2025-06-21T06:13:00
permalink Post: 11907514
Hoover from the generally respected Pilot Debrief channel put up his analysis.
He analyses the point of rotation looking at the airport layout and using the video with the shack showing the aircraft rotate behind it, in that case the aircraft rotates at a reasonably normal place. That being the case what is the "cloud of particles" that appear to the left of the aircraft ?
He discounts electrical failure affecting both engines due 787 design, and fuel contamination due both engines fed from separate tanks unlikely to affect both engines at the same time.
The possibility that one engine failure occurred at a critical point in the take off and that possibly the wrong engine fuel cutoff switch was pulled.
camera angle with shack and suggested point of rotation
whats this..
He analyses the point of rotation looking at the airport layout and using the video with the shack showing the aircraft rotate behind it, in that case the aircraft rotates at a reasonably normal place. That being the case what is the "cloud of particles" that appear to the left of the aircraft ?
He discounts electrical failure affecting both engines due 787 design, and fuel contamination due both engines fed from separate tanks unlikely to affect both engines at the same time.
The possibility that one engine failure occurred at a critical point in the take off and that possibly the wrong engine fuel cutoff switch was pulled.
camera angle with shack and suggested point of rotation
whats this..
1 user liked this post.
2025-06-21T06:36:00
permalink Post: 11907525
Hoover from the generally respected Pilot Debrief channel put up his analysis.
He analyses the point of rotation looking at the airport layout and using the video with the shack showing the aircraft rotate behind it, in that case the aircraft rotates at a reasonably normal place. That being the case what is the "cloud of particles" that appear to the left of the aircraft ?
He discounts electrical failure affecting both engines due 787 design, and fuel contamination due both engines fed from separate tanks unlikely to affect both engines at the same time.
The possibility that one engine failure occurred at a critical point in the take off and that possibly the wrong engine fuel cutoff switch was pulled.
camera angle with shack and suggested point of rotation
whats this..
He analyses the point of rotation looking at the airport layout and using the video with the shack showing the aircraft rotate behind it, in that case the aircraft rotates at a reasonably normal place. That being the case what is the "cloud of particles" that appear to the left of the aircraft ?
He discounts electrical failure affecting both engines due 787 design, and fuel contamination due both engines fed from separate tanks unlikely to affect both engines at the same time.
The possibility that one engine failure occurred at a critical point in the take off and that possibly the wrong engine fuel cutoff switch was pulled.
camera angle with shack and suggested point of rotation
whats this..
I repeat, do NOT post repeats of discussions already had unless there is something of value which may change or enhance previous posts. This is a prime example of a post which should be vetted and dismissed before pressing Submit Reply 🙈
6 users liked this post.
2025-06-21T07:19:00
permalink Post: 11907541
The possibility that one engine failure occurred at a critical point in the take off and that possibly the wrong engine fuel cutoff switch was pulled.
Where the meme has come from that jet pilots have to shut down engines as quickly as possible I don\x92t know but it is incorrect. If you left a failed engine without securing it for 5 minutes, little to no harm would come of it. Even if it was on fire (which is not necessarily flames, just higher than normal temperatures inside the nacelle) they are certified to be in this condition for some considerable time before it becomes a problem. Yes, I think the phrase \x93without undue delay\x94 could be used for a fire indication but that\x92s a minimum of 400\x92AGL in Boeings and does not absolve you of all the cross-checking and CRM that should happen with an engine shutdown. This is practiced/checked at the least every 6 months in EASA land and any attempt to rush a shutdown at low level would lead to a debrief and more training/checking.
To put it this way, control of the aeroplane and lateral/vertical navigation is far more important than doing stuff with a failed power plant. Something like an ET should be absolutely prioritised over engine drills.
8 users liked this post.
2025-06-21T08:56:00
permalink Post: 11907591
The issues with the "they shut down the wrong engine" theory:
1. No asymmetry evidence with flight path deviation. No roll, no yaw effects
2. No rudder inputs visible.
3. No crew should be doing memory items below 400ft. Boeing requires each crew member confirm together memory item switch/control selections.
4. Non-normal gear truck tilt position, a one engine failure should not affect the C hydraulics. As per (3) gear would be selected Up before any memory actions.
The evidence so far is an almost simultaneous dual engine failure, which rules out alot of other theories.
1. No asymmetry evidence with flight path deviation. No roll, no yaw effects
2. No rudder inputs visible.
3. No crew should be doing memory items below 400ft. Boeing requires each crew member confirm together memory item switch/control selections.
4. Non-normal gear truck tilt position, a one engine failure should not affect the C hydraulics. As per (3) gear would be selected Up before any memory actions.
The evidence so far is an almost simultaneous dual engine failure, which rules out alot of other theories.
7 users liked this post.
2025-06-21T13:50:00
permalink Post: 11907770
The issues with the "they shut down the wrong engine" theory:
1. No asymmetry evidence with flight path deviation. No roll, no yaw effects
2. No rudder inputs visible.
3. No crew should be doing memory items below 400ft. Boeing requires each crew member confirm together memory item switch/control selections.
4. Non-normal gear truck tilt position, a one engine failure should not affect the C hydraulics. As per (3) gear would be selected Up before any memory actions.
The evidence so far is an almost simultaneous dual engine failure, which rules out alot of other theories.
1. No asymmetry evidence with flight path deviation. No roll, no yaw effects
2. No rudder inputs visible.
3. No crew should be doing memory items below 400ft. Boeing requires each crew member confirm together memory item switch/control selections.
4. Non-normal gear truck tilt position, a one engine failure should not affect the C hydraulics. As per (3) gear would be selected Up before any memory actions.
The evidence so far is an almost simultaneous dual engine failure, which rules out alot of other theories.