July 09, 2025, 23:20:00 GMT
permalink Post: 11918695
There has been discussion recently about a procedure that involves moving the fuel switches to CUTOFF and then back to RUN following a dual engine failure.
Attached is an image of a page from the Air India 787 Training Manual that discusses this procedure.
I am submitting this without comment or opinion.
Attached is an image of a page from the Air India 787 Training Manual that discusses this procedure.
I am submitting this without comment or opinion.
July 10, 2025, 00:21:00 GMT
permalink Post: 11918716
Obviously, because it's going to require quick action to catch high RPM. And maybe that's what they tried.
It also seems to be indicating that fuel switch resetting should be attempted if the restart has failed to start the engine?
July 10, 2025, 06:42:00 GMT
permalink Post: 11918780
It is not inconceivable to me that a human being who THINKS they've had a dual engine failure at possibly the worst time imaginable (correctly or incorrectly) and has not taken the time to confirm, or take it all in and has immediately launched into memory items. I could certainly foresee one being rather startled by the energy state and the rapidly approaching buildings.
I'm not saying that this happened to this crew but it certainly could happen to someone. People do weird !!!! under high stress. There is an initial "oh !!!!, what's going on" then the training kicks in. Often at super fast rate and the challenge becomes slowing it all down.
The bloody master warning on the Airbus for smoke in the forward Lav used to get me everytime. Was always at night over the ocean too.
I'm not saying that this happened to this crew but it certainly could happen to someone. People do weird !!!! under high stress. There is an initial "oh !!!!, what's going on" then the training kicks in. Often at super fast rate and the challenge becomes slowing it all down.
The bloody master warning on the Airbus for smoke in the forward Lav used to get me everytime. Was always at night over the ocean too.
July 10, 2025, 08:26:00 GMT
permalink Post: 11918827
It is not inconceivable to me that a human being who THINKS they've had a dual engine failure at possibly the worst time imaginable (correctly or incorrectly) and has not taken the time to confirm, or take it all in and has immediately launched into memory items. I could certainly foresee one being rather startled by the energy state and the rapidly approaching buildings.
I'm not saying that this happened to this crew but it certainly could happen to someone. People do weird !!!! under high stress. There is an initial "oh !!!!, what's going on" then the training kicks in. Often at super fast rate and the challenge becomes slowing it all down.
The bloody master warning on the Airbus for smoke in the forward Lav used to get me everytime. Was always at night over the ocean too.
I'm not saying that this happened to this crew but it certainly could happen to someone. People do weird !!!! under high stress. There is an initial "oh !!!!, what's going on" then the training kicks in. Often at super fast rate and the challenge becomes slowing it all down.
The bloody master warning on the Airbus for smoke in the forward Lav used to get me everytime. Was always at night over the ocean too.
July 10, 2025, 08:59:00 GMT
permalink Post: 11918849
A couple of points if I may......
I don't see it written in the 787 FCOM but I have always been told that the action of resetting the Engine Cutoff switches in the event of a dual engine failure, is merely backing up what the FADECs have already done. If there is an 'engine event' the FADECs will manage ignition and fuel-flow to restore the thrust that was demanded before the event. If that management has failed then the manual resetting may be more successful. (The same holds true for the RAT, manual selection is merely backing up the auto-deployment).
Any airline pilot will tell you that executing an in-flight relight on a big engine, no matter if it is by electric start, windmilling RPM or cross-bleed assisted, can take between 1 and 3 minutes to restore power. This aircraft was airborne for less that 30 seconds. No pilot in his right mind would prioritise an in-flight relight procedure, in a situation where they had neither the time, the height nor the speed for it to succeed. I have no doubt the crew focussed entirely on pointing the aircraft at the clearest area they could see, to mitigate what would inevitably follow.
I don't see it written in the 787 FCOM but I have always been told that the action of resetting the Engine Cutoff switches in the event of a dual engine failure, is merely backing up what the FADECs have already done. If there is an 'engine event' the FADECs will manage ignition and fuel-flow to restore the thrust that was demanded before the event. If that management has failed then the manual resetting may be more successful. (The same holds true for the RAT, manual selection is merely backing up the auto-deployment).
Any airline pilot will tell you that executing an in-flight relight on a big engine, no matter if it is by electric start, windmilling RPM or cross-bleed assisted, can take between 1 and 3 minutes to restore power. This aircraft was airborne for less that 30 seconds. No pilot in his right mind would prioritise an in-flight relight procedure, in a situation where they had neither the time, the height nor the speed for it to succeed. I have no doubt the crew focussed entirely on pointing the aircraft at the clearest area they could see, to mitigate what would inevitably follow.
July 10, 2025, 13:18:00 GMT
permalink Post: 11919024
The data recorder has all the information most are questioning. They already know if the fuel control switches were selected to cutoff and they know if this happened before or after the loss of thrust. Perhaps the sequence of events will be more clear tomorrow. I can tell you that from aircraft rotation to loss of thrust was a very short time period. Perhaps 8 seconds. I simply won’t believe in that time period the crew were taking any non deliberate actions that would have shut the motors down.
- They know exactly 1 fuel switch was cut off, perhaps implying single engine failure + wrong engine shutdown
- They know 1 or both switches were cycled off then on, implying a last-ditch attempt at some sort reset at any point up to say ~30s
- They know both fuel switches were cut off, and remained off, implying sabotage
- If the cut off happened within 20s of leaving the ground perhaps it could explain why CCTV shows the initial climb then level for ~10s before descent. It could also explain the RAT and gear trucks perhaps if gear up was delayed? However, in this scenario they must know that the engine failed, that information would be clearly recorded and surely the leak would lead with that info? Also 'switches' is plural implying both, the radio call didn't mention single engine failure and like you say its quite hasty, even within 20s.
- Again assuming switches plural, this implies either of the prevailing theories of dual engine failure leading to loss of AC or loss of AC leading to reduced thrust or engine failure. However, it also seems strange to lead with that info rather than the state of the engines or electrical systems in any flight data, unless someone can explain how the data would be impacted?
- If this was the case then it would imply that there is no voice or engine data to explain the cut off, nothing was said and the engines were normal up until that point
July 10, 2025, 14:12:00 GMT
permalink Post: 11919049
Originally Posted by
"Capn Bloggs
So, we have a Memory Drill with a non-numbered thing you have to remember first, being sub-idle, and an FCTM that pumps the idea of getting those switches off and on ASAP, before the revs drop off too much, at any speed or altitude.
Great.
Great.
Notwithstanding what it says in the B787 FCOM and FCTM, I don't think Boeing ever envisaged the dual engine failure procedure being required 10 seconds after rotate. There are many pilots in civil aviation who live and die by what is written in the manuals without thinking past the text. There are times when what is written is sensible and appropriate, and there are times when application is just plain daft. This is why a man is in charge, not a machine.
For those thinking about a SEF followed by an incorrect shutdown..... In the event of a SEF you control the aircraft, take the gear up and engage the autopilot. You then sit on your hands until 400' AGL. If an engine is on fire - You let it burn until 400'. No procedure is actioned until the problem is confirmed between you, and you are safely climbing away. To deviate from that would be very unprofessional and highly dangerous.
July 10, 2025, 15:53:00 GMT
permalink Post: 11919101
That does not mean that the pilots "out of habit" would have reverted to the procedure. Who would not? But in that case, the fuel control switches would be found in the RUN position post crash (if anything was left). So did they find the switches in the cutoff position, or did the action of switching got "stored" somewhere in FDM (not a specialist on these things, only to hear many times in the past that "maintenance is already aware" if we had an issue and called maintenance post flight)
July 11, 2025, 22:09:00 GMT
permalink Post: 11919886
Seconds count:
Time was spent with the verbal exchange, and then perhaps each pilot expected the other to put the switch back?
Anyway, the preliminary report also establishes that the aircraft had only 3-4 seconds of powered flight. (Would the gear lever be operated that early?) Everyone who saw that from the CCTV video, pat yourselves on the back.
Mayday call, dual engine failure, RAT deployment all confirmed.
TCMA was a red herring, the aircraft was firmly in air mode as the accident unfolded, and the thrust levers were at takeoff thrust the whole time.
As per the EAFR, the Engine 1 fuel cutoff switch transitioned from CUTOFF to RUN at about
08:08:52 UTC. The APU Inlet Door began opening at about 08:08:54 UTC, consistent with the APU Auto Start logic. Thereafter at 08:08:56 UTC the Engine 2 fuel cutoff switch also transitions from CUTOFF to RUN. When fuel control switches are moved from CUTOFF to RUN while the aircraft is inflight, each engines full authority dual engine control (FADEC) automatically manages a relight and thrust recovery sequence of ignition and fuel introduction. The EGT was observed to be rising for both engines indicating relight.
Engine 1's 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 UTC.
That was with 10 seconds delay vs. 13 seconds for engine 2.
Time was spent with the verbal exchange, and then perhaps each pilot expected the other to put the switch back?
Anyway, the preliminary report also establishes that the aircraft had only 3-4 seconds of powered flight. (Would the gear lever be operated that early?) Everyone who saw that from the CCTV video, pat yourselves on the back.
Mayday call, dual engine failure, RAT deployment all confirmed.
TCMA was a red herring, the aircraft was firmly in air mode as the accident unfolded, and the thrust levers were at takeoff thrust the whole time.
July 11, 2025, 22:12:00 GMT
permalink Post: 11919889
Spoiler
I wouldn't put too much significance in the "01 second" since this still is close enough for an unintentional cause.
No matter what: The design and position of the fuel cut off switches is potentially prone for mishaps.
July 11, 2025, 22:15:00 GMT
permalink Post: 11919893
For those sky gods who confidently state they would reset the cutoff switches immediately I would say that 10 seconds is not a particularly unusual time for startle effect to impair cognition, especially for something as monumental and unexpected as a dual engine failure at rotation. One reference amongst many:
https://www.icao.int/Meetings/LOCI/P...Strategies.pdf
And for those who scoff at the possibility of the PM inadvertently operating the cutoff switches (which is done as frequently as operating the gear lever), I\x92d remind you that more than one Airbus has landed with its parking brake on after the PM inadvertently set it rather than arming the spoilers.
And for those who scoff at the possibility of the PM inadvertently operating the cutoff switches (which is done as frequently as operating the gear lever), I\x92d remind you that more than one Airbus has landed with its parking brake on after the PM inadvertently set it rather than arming the spoilers.
July 11, 2025, 22:17:00 GMT
permalink Post: 11919895
Background
The Boeing Company (Boeing) received reports from operators of Model 737 airplanes that the fuel control switches were installed with the locking feature disengaged. The fuel control switches (or engine start switches) are installed on the control stand in the flight deck and used by the pilot to supply or cutoff fuel to the engines. The fuel control switch has a locking feature to prevent inadvertent operation that could result in unintended switch movement between the fuel supply and fuel cutoff positions. In order to move the switch from one position to the other under the condition where the locking feature is engaged, it is necessary for the pilot to lift the switch up while transitioning the switch position. If the locking feature is disengaged, the switch can be moved between the two positions without lifting the switch during transition, and the switch would be exposed to the potential of inadvertent operation. Inadvertent operation of the switch could result in an unintended consequence, such as an in-flight engine shutdown.
...The table below identifies the affected airplane models and related part numbers (P/Ns) of the fuel control switch, which is manufactured by Honeywell.
...787-8, -9, and -10
The Boeing Company (Boeing) received reports from operators of Model 737 airplanes that the fuel control switches were installed with the locking feature disengaged. The fuel control switches (or engine start switches) are installed on the control stand in the flight deck and used by the pilot to supply or cutoff fuel to the engines. The fuel control switch has a locking feature to prevent inadvertent operation that could result in unintended switch movement between the fuel supply and fuel cutoff positions. In order to move the switch from one position to the other under the condition where the locking feature is engaged, it is necessary for the pilot to lift the switch up while transitioning the switch position. If the locking feature is disengaged, the switch can be moved between the two positions without lifting the switch during transition, and the switch would be exposed to the potential of inadvertent operation. Inadvertent operation of the switch could result in an unintended consequence, such as an in-flight engine shutdown.
...The table below identifies the affected airplane models and related part numbers (P/Ns) of the fuel control switch, which is manufactured by Honeywell.
...787-8, -9, and -10
Last edited by 13 others; 12th July 2025 at 01:40 . Reason: Bold emphasis mine, fixed link
July 11, 2025, 23:25:00 GMT
permalink Post: 11919990
There is mention of fire damage or thermal damage to the centre pedestal, perhaps enough to identify the position of the switches but not to be able to determine their internal physical state relating to the detent mechanisms.
For myself, I have total confidence that the switches functioned as intended. Obviously they commanded the fuel valve as intended, and can be seen intact (other than the plastic caps), and in the run position, so it is safe to conclude that a mechanical/electrical fault of both independent switches at the same moment is unlikely in the extreme. The FDR data states that they were moved to "off" position, which caused the engine shutdown, then returned to "run", so they obviously were mechanically and electrically functional.
The automatic deployment of the RAT is an indicator of the airplane systems sensing an engine shutdown, as is the APU autostart. Pax 11A mentioned the green cabin lights, which, if I understand correctly is an indication of a complete electrical generation failure.The time of all these events can be plotted from recorded data, which I expect we'll see in a full report later. In the mean time, it all makes unfortunate sense.
July 12, 2025, 02:41:00 GMT
permalink Post: 11920113
There is an EICAS message that comes up when an engine is shutdown (there is a small delay), which might prompt them to look at the switch - or just the sound the switch makes could prompt a quick glance down at the switch.
July 12, 2025, 03:55:00 GMT
permalink Post: 11920158
Again I agree with you, 3 seconds is about right for positive rate, I would be starting to lean over toward the gear handle about then. So did the start switches manually move to shutoff or not, if not then, they must have been manually cycled off to run 10 seconds later and what raised the "why did you" query, wouldn't that query be "dual engine failure"
July 12, 2025, 06:40:00 GMT
permalink Post: 11920252
Language
Language:
Having lived in the Middle East for over 20 years, I am somewhat used to the Indian use of the English language. Therefore, I wouldn't look too closely at the usage of "transitioned"; it simply means moving from one condition to another.
The conversation of the pilots, on the other hand, will be very interesting. It should be analysed in the language they were speaking, considering whether this was their native language to start with. I assume that the conversation was in Hindi, translated to English for the report. In that case alone, a lot of nuance might have been lost in translation. That's without even considering the tone, volume etc. of the conversation.
Procedure:
I am an Airbus driver, so I am not familiar with the B787 EICAS. On the Bus, the ECAM would generate an ENG FAIL, followed shortly thereafter by an ENG ALL ENGINE FAILURE. I assume the B787 would have a similar event on the EICAS. Now, considering the time frame of how quickly things happened, there is absolutely no reason for the pilots to assume something was wrong with both engine cutoffs, unless they were physically switched off by someone. We are not trained to consider a fuel cutoff switch as the main reason for an engine failure, especially on the takeoff roll.
Question?
When I was a young F/O, some of the captains I flew with had the (annoying) habit of resting their hands just behind the thrust levers on their PM (PNF) sectors to 'be ready' to reject the takeoff. This would put the hands in the vicinity of the Fuel Cutoffs, which would, in turn, increase the chances of an unintended action on these switches. Is this a possibility, or am I way off?
Having lived in the Middle East for over 20 years, I am somewhat used to the Indian use of the English language. Therefore, I wouldn't look too closely at the usage of "transitioned"; it simply means moving from one condition to another.
The conversation of the pilots, on the other hand, will be very interesting. It should be analysed in the language they were speaking, considering whether this was their native language to start with. I assume that the conversation was in Hindi, translated to English for the report. In that case alone, a lot of nuance might have been lost in translation. That's without even considering the tone, volume etc. of the conversation.
Procedure:
I am an Airbus driver, so I am not familiar with the B787 EICAS. On the Bus, the ECAM would generate an ENG FAIL, followed shortly thereafter by an ENG ALL ENGINE FAILURE. I assume the B787 would have a similar event on the EICAS. Now, considering the time frame of how quickly things happened, there is absolutely no reason for the pilots to assume something was wrong with both engine cutoffs, unless they were physically switched off by someone. We are not trained to consider a fuel cutoff switch as the main reason for an engine failure, especially on the takeoff roll.
Question?
When I was a young F/O, some of the captains I flew with had the (annoying) habit of resting their hands just behind the thrust levers on their PM (PNF) sectors to 'be ready' to reject the takeoff. This would put the hands in the vicinity of the Fuel Cutoffs, which would, in turn, increase the chances of an unintended action on these switches. Is this a possibility, or am I way off?
July 12, 2025, 07:22:00 GMT
permalink Post: 11920273
In my career in a regional airline (turboprops) I recall a number of episodes where completely inappropriate control actions were effected, on one occasion by an aircraft crewed by both the chief pilot and GMFO.
1 parking brake selected on touch down instead of control lock \x85blew all tyres.
2 FO selected disking on props instead of reduced rpm..corrected by swift action of co pilot
3 Captain pulled both T handles after mis identifying an erroneous auto feather operation as engine failure. Saved by swift action of co pilot\x85
conclusion\x85 pilots can do the craziest things without malevolence.
CRM and design mitigate the risks but I have to confess surprise at the close location of these switches to the thrust levers and apparent ease of operation.
just a thought\x85.on light piston aircraft an action after to is to shut off fuel booster pumps\x85\x85
Did one of the pilots forget what he was flying for a second and revert to sub conscious action relevant to previous type\x85..??
1 parking brake selected on touch down instead of control lock \x85blew all tyres.
2 FO selected disking on props instead of reduced rpm..corrected by swift action of co pilot
3 Captain pulled both T handles after mis identifying an erroneous auto feather operation as engine failure. Saved by swift action of co pilot\x85
conclusion\x85 pilots can do the craziest things without malevolence.
CRM and design mitigate the risks but I have to confess surprise at the close location of these switches to the thrust levers and apparent ease of operation.
just a thought\x85.on light piston aircraft an action after to is to shut off fuel booster pumps\x85\x85
Did one of the pilots forget what he was flying for a second and revert to sub conscious action relevant to previous type\x85..??
July 12, 2025, 11:09:00 GMT
permalink Post: 11920506
On this flight, the relative drop in noise and calm that follows the landing gear doors closing after the gear retracts during the initial climb, might have caused an action slip by PIC to perform the engine shut-down procedure used when parking on stand.
Unlikely though, I would hope.
July 12, 2025, 11:22:00 GMT
permalink Post: 11920523
This crossed my mind too. This is called an "action-slip" by designers: a valid and frequently practised action being applied to entirely the wrong situation, resulting in an (extremely) invalid action.
On this flight, the relative drop in noise and calm that follows the landing gear doors closing after the gear retracts during the initial climb, might have caused an action slip by PIC to perform the engine shut-down procedure used when parking on stand.
Unlikely though, I would hope.
On this flight, the relative drop in noise and calm that follows the landing gear doors closing after the gear retracts during the initial climb, might have caused an action slip by PIC to perform the engine shut-down procedure used when parking on stand.
Unlikely though, I would hope.
Action slip in general... technically possible, but there should still be no actions being taken other than gear up (and probably still a bit early for that).
Engines off instead of gear up is one hell of an action slip.
July 12, 2025, 11:32:00 GMT
permalink Post: 11920533
Originally Posted by
Uplinker
This might have been discussed but as has been suggested upthread; a possible scenario is that at some point, PIC took their hands off the thrust levers and/or placed them in a guarding position behind the thrust levers at their base - but by doing so unfortunately nudged the Fuel cut-off switches to 'Off' - perhaps 'helped' by there either being incorrectly fitted locking mechanisms or worn locking mechanisms ?
Originally Posted by
Uplinker
On this flight, the relative drop in noise and calm that follows the landing gear doors closing after the gear retracts during the initial climb, might have caused an action slip by PIC to perform the engine shut-down procedure used when parking on stand.
Mods, if you don't lock the thread, I'm going back to Facebook!
