July 11, 2025, 20:30:00 GMT
permalink Post: 11919765
From the Report:
The aircraft achieved the maximum recorded airspeed of 180 Knots IAS at about 08:08:42 UTC and immediately thereafter, the Engine 1 and Engine 2 fuel cutoff switches transitioned from RUN to CUTOFF position one after another with a time gap of 01 sec. The Engine N1 and N2 began to decrease from their take-off values as the fuel supply to the engines was cut off.
In the cockpit voice recording, one of the pilots is heard asking the other why did he cutoff.
The other pilot responded that he did not do so.
In the cockpit voice recording, one of the pilots is heard asking the other why did he cutoff.
The other pilot responded that he did not do so.
July 11, 2025, 20:40:00 GMT
permalink Post: 11919772
The aircraft achieved the maximum recorded airspeed of 180 Knots IAS at about 08:08:42
UTC and immediately thereafter, the Engine 1 and Engine 2 fuel cutoff switches transitioned
from RUN to CUTOFF position one after another with a time gap of 01 sec. The Engine N1
and N2 began to decrease from their take-off values as the fuel supply to the engines was cut
off.
In the cockpit voice recording, one of the pilots is heard asking the other why did he cutoff.
The other pilot responded that he did not do so.
The CCTV footage obtained from the airport showed Ram Air Turbine (RAT) getting deployed
during the initial climb immediately after lift-off (fig. 15). No significant bird activity is observed
in the vicinity of the flight path. The aircraft started to lose altitude before crossing the airport
perimeter wall.
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
As per the EAFR data both engines N2 values passed below minimum idle speed, and the
RAT hydraulic pump began supplying hydraulic power at about 08:08:47 UTC.
RAT in extended position
15
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
At about 08:09:05 UTC, one of the pilots transmitted “MAYDAY MAYDAY MAYDAY”.
UTC and immediately thereafter, the Engine 1 and Engine 2 fuel cutoff switches transitioned
from RUN to CUTOFF position one after another with a time gap of 01 sec. The Engine N1
and N2 began to decrease from their take-off values as the fuel supply to the engines was cut
off.
In the cockpit voice recording, one of the pilots is heard asking the other why did he cutoff.
The other pilot responded that he did not do so.
The CCTV footage obtained from the airport showed Ram Air Turbine (RAT) getting deployed
during the initial climb immediately after lift-off (fig. 15). No significant bird activity is observed
in the vicinity of the flight path. The aircraft started to lose altitude before crossing the airport
perimeter wall.
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
As per the EAFR data both engines N2 values passed below minimum idle speed, and the
RAT hydraulic pump began supplying hydraulic power at about 08:08:47 UTC.
RAT in extended position
15
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
At about 08:09:05 UTC, one of the pilots transmitted “MAYDAY MAYDAY MAYDAY”.
08:08:42 Engine 1 and Engine 2 fuel cutoff switches transitioned from RUN to CUTOFF position.
One of the pilots asks the other why did he cutoff.
The other pilot responded that he did not do so.
08:08:52 Engine 1 fuel cutoff switch transitioned from CUTOFF to RUN
08:08:56 Engine 2 fuel cutoff switch also transitions from CUTOFF to RUN
Who (or what?) operated the cutoff switches?
Last edited by Engineless; 11th July 2025 at 20:53 .
July 11, 2025, 21:24:00 GMT
permalink Post: 11919826
What the hell happened in the cockpit?
08:08:42 Engine 1 and Engine 2 fuel cutoff switches transitioned from RUN to CUTOFF position.
One of the pilots asks the other why did he cutoff.
The other pilot responded that he did not do so.
08:08:52 Engine 1 fuel cutoff switch transitioned from CUTOFF to RUN
08:08:56 Engine 2 fuel cutoff switch also transitions from CUTOFF to RUN
Who (or what?) operated the cutoff switches?
08:08:42 Engine 1 and Engine 2 fuel cutoff switches transitioned from RUN to CUTOFF position.
One of the pilots asks the other why did he cutoff.
The other pilot responded that he did not do so.
08:08:52 Engine 1 fuel cutoff switch transitioned from CUTOFF to RUN
08:08:56 Engine 2 fuel cutoff switch also transitions from CUTOFF to RUN
Who (or what?) operated the cutoff switches?
Does the FDR actually have some input of the physical position of the switches or is it just measuring the output signal voltage
which might be changed by a momentary short from liquid or swarf.
Both signals go to cutoff within 1 second but then one recovers four seconds after the other.
Surely a pilot discovering a turned off switch would have both back on in less than four seconds.
July 11, 2025, 21:54:00 GMT
permalink Post: 11919862
So, yes, switches.
either
1/deliberately cut off by someone in the cockpit, or
2/placed in an intermediate gate position possible due to wear or wrong installation, happens during engine start, and then vibrates or bumps to cut-off during the take off roll or
3/some kind of liquid or other contamination in the LRU shorting both and cycling them after 8 seconds brought them electrically back to RUN.
Anyone got other ideas?
either
1/deliberately cut off by someone in the cockpit, or
2/placed in an intermediate gate position possible due to wear or wrong installation, happens during engine start, and then vibrates or bumps to cut-off during the take off roll or
3/some kind of liquid or other contamination in the LRU shorting both and cycling them after 8 seconds brought them electrically back to RUN.
Anyone got other ideas?
I would have thought a pilot would notice the engines spooling down, and comment on that. To immediately jump to the cutoff switches as the cause rather implies something drew attention to the switches.
Then there is a 10+ second gap before the switches are set to run again. I can't think of any good reason why the PNF would have taken so long to correct an accidental or deliberate manipulation of the switches.
July 11, 2025, 22:06:00 GMT
permalink Post: 11919877
In the case of (2) or (3), would the expected response be "Why did you cutoff"?
I would have thought a pilot would notice the engines spooling down, and comment on that. To immediately jump to the cutoff switches as the cause rather implies something drew attention to the switches.
Then there is a 10+ second gap before the switches are set to run again. I can't think of any good reason why the PNF would have taken so long to correct an accidental or deliberate manipulation of the switches.
I would have thought a pilot would notice the engines spooling down, and comment on that. To immediately jump to the cutoff switches as the cause rather implies something drew attention to the switches.
Then there is a 10+ second gap before the switches are set to run again. I can't think of any good reason why the PNF would have taken so long to correct an accidental or deliberate manipulation of the switches.
You need to take the audio together with the switch data, not in isolation.
The two combined would appear to rule out a lot of options that the data alone would leave possible.
July 11, 2025, 22:16:00 GMT
permalink Post: 11919894
From the report, there is no indicated time stamp identifying the point when one pilot asked the other "why did you cut off"
This could explain the the assumption that it took ten seconds to reverse the switch positions.
Cut off could have been noticed at any point later than 08:08:42 but before 08:08:52.
This could explain the the assumption that it took ten seconds to reverse the switch positions.
Cut off could have been noticed at any point later than 08:08:42 but before 08:08:52.
July 11, 2025, 22:18:00 GMT
permalink Post: 11919902
There are two options. The fuel cut off was accidental or it was deliberate. The question from one of the pilots is why did you do that? The other pilot denied it.
The fuel was cut off but restored too late.
The 'why did you do that' question is significant. It wasn't 'What happened?' or 'How did that happen'
Of course it could have happened accidentally. 757 pilots might have input.
The fuel was cut off but restored too late.
The 'why did you do that' question is significant. It wasn't 'What happened?' or 'How did that happen'
Of course it could have happened accidentally. 757 pilots might have input.
In the cockpit voice recording, one of the pilots is heard asking the other why did he cutoff.
The other pilot responded that he did not do so.
The other pilot responded that he did not do so.
July 11, 2025, 22:33:00 GMT
permalink Post: 11919922
The phrasing
\x93Why did you cut off?\x94
doesn\x92t suggest surprise at an EICAS message, it implies direct observation or perception of manual action. This quote from the preliminary report reads exactly like what it appears to be; one pilot reacting to a control input he didn\x92t expect for which there was no plausible explanation .
The report simply says:
In the cockpit voice recording, one of the pilots is heard asking the other why did he cutoff.
The other pilot responded that he did not do so.
The other pilot responded that he did not do so.
July 12, 2025, 00:08:00 GMT
permalink Post: 11920029
Timeline of known events with source attribution from the preliminary report:
08:07:33 ATC: Takeoff clearance
08:07:37 A-SMGCS: Aircraft starts rolling
08:08:33 EAFR: V1 153kts
08:08:35 EAFR: Vr 155kts
08:08:39 EAFR: Gnd-Air mode transition
08:08:42 EAFR: Max IAS 180kts, Eng 1/2 Cutoff switches activate within 1 second of each other
08:08:42 CVR: "Why did you cut off", "I did not" (exact time not specified)
08:08:42 A-SMGCS: RAT deployed (exact time not specified)
08:08:47 EAFR: Both engine N2 below min idle. RAT hyd pwr commences
08:08:52 EAFR: Eng 1 cutoff to RUN
08:08:54 EAFR: APU inlet door opens (auto start logic)
08:08:56 EAFR: Eng 2 cutoff to RUN
08:09:05 ATC: Mayday call
08:09:11 EAFR recording stops
Fuel cutoff switches operated within 1 second of each other suggests to me that the locking mechanism wasn't working as per (SAIB) No. NM-18-33. Any loose item could have accidentally (or not) operated the switches (including hands).
08:07:33 ATC: Takeoff clearance
08:07:37 A-SMGCS: Aircraft starts rolling
08:08:33 EAFR: V1 153kts
08:08:35 EAFR: Vr 155kts
08:08:39 EAFR: Gnd-Air mode transition
08:08:42 EAFR: Max IAS 180kts, Eng 1/2 Cutoff switches activate within 1 second of each other
08:08:42 CVR: "Why did you cut off", "I did not" (exact time not specified)
08:08:42 A-SMGCS: RAT deployed (exact time not specified)
08:08:47 EAFR: Both engine N2 below min idle. RAT hyd pwr commences
08:08:52 EAFR: Eng 1 cutoff to RUN
08:08:54 EAFR: APU inlet door opens (auto start logic)
08:08:56 EAFR: Eng 2 cutoff to RUN
08:09:05 ATC: Mayday call
08:09:11 EAFR recording stops
Fuel cutoff switches operated within 1 second of each other suggests to me that the locking mechanism wasn't working as per (SAIB) No. NM-18-33. Any loose item could have accidentally (or not) operated the switches (including hands).
Last edited by physicus; 12th July 2025 at 00:24 .
July 12, 2025, 01:15:00 GMT
permalink Post: 11920061
"The other pilot responded that he did not do so."
Exact wording is not provided, so maybe it was "what the hell are you talking about?" or maybe it was "I didn't". If I was the FO and the Captain asked "why did you cutoff?" and I hadn't, I would reply "I didn't". If the conversation was in the other direction it might be different.
No doubt expert analysis of the voice recording is underway.
July 12, 2025, 01:28:00 GMT
permalink Post: 11920070
Can someone with the engineering knowledge build a timeline/timeframe for fuel cutoff switch RUN to CUTOFF -> fuel stops -> engine flameout -> N2 drops to ? -> VFSGs quit -> RAT deployment starts -> RAT full power -> APU deployment start?
Does the RAT really start providing power in 4 seconds from the E2 fuel cutoff switch RUN -> CUTOFF?
Timeline from AAIB and the public CCTV video:
08:08:33 v1 153 kts
.
08:08:35 vr 155 kts
.
.
.
08:08:39 Liftoff, A/G Air Mode, rotation at 00:18 in public CCTV video
.
.
08:08:42 E1 Fuel Cutoff Switch RUN -> CUTOFF, 180 kts
08:08:43 E2 Fuel Cutoff Switch RUN -> CUTOFF
.............? N1 N2 begin to decrease
.............? "Why did you cutoff", "I didn't"
.............? Airport CCTV shows RAT
.............? N2 < idle speed
08:08:47 RAT hydraulic power
.
08:08:49 Public CCTV video: visible loss of thrust, Alt < 200ft using wingspan
.
.
08:08:52 E1 Fuel Cutoff Switch CUTOFF -> RUN, CCTV video: visible descent
.
08:08:54 APU inlet door begins opening
.
08:08:56 E2 Fuel Cutoff Switch CUTOFF -> RUN
08:09:05 MAYDAY
08:09:11 EAFR Recording stops
08:14:44 Crash Fire Tender leaves airport
Does the RAT really start providing power in 4 seconds from the E2 fuel cutoff switch RUN -> CUTOFF?
Timeline from AAIB and the public CCTV video:
08:08:33 v1 153 kts
.
08:08:35 vr 155 kts
.
.
.
08:08:39 Liftoff, A/G Air Mode, rotation at 00:18 in public CCTV video
.
.
08:08:42 E1 Fuel Cutoff Switch RUN -> CUTOFF, 180 kts
08:08:43 E2 Fuel Cutoff Switch RUN -> CUTOFF
.............? N1 N2 begin to decrease
.............? "Why did you cutoff", "I didn't"
.............? Airport CCTV shows RAT
.............? N2 < idle speed
08:08:47 RAT hydraulic power
.
08:08:49 Public CCTV video: visible loss of thrust, Alt < 200ft using wingspan
.
.
08:08:52 E1 Fuel Cutoff Switch CUTOFF -> RUN, CCTV video: visible descent
.
08:08:54 APU inlet door begins opening
.
08:08:56 E2 Fuel Cutoff Switch CUTOFF -> RUN
08:09:05 MAYDAY
08:09:11 EAFR Recording stops
08:14:44 Crash Fire Tender leaves airport
Last edited by appruser; 12th July 2025 at 01:29 . Reason: readability
July 12, 2025, 02:39:00 GMT
permalink Post: 11920112
What the hell happened in the cockpit?
08:08:42 Engine 1 and Engine 2 fuel cutoff switches transitioned from RUN to CUTOFF position.
One of the pilots asks the other why did he cutoff.
The other pilot responded that he did not do so.
08:08:52 Engine 1 fuel cutoff switch transitioned from CUTOFF to RUN
08:08:56 Engine 2 fuel cutoff switch also transitions from CUTOFF to RUN
Who (or what?) operated the cutoff switches?
08:08:42 Engine 1 and Engine 2 fuel cutoff switches transitioned from RUN to CUTOFF position.
One of the pilots asks the other why did he cutoff.
The other pilot responded that he did not do so.
08:08:52 Engine 1 fuel cutoff switch transitioned from CUTOFF to RUN
08:08:56 Engine 2 fuel cutoff switch also transitions from CUTOFF to RUN
Who (or what?) operated the cutoff switches?
What observation(s) would or could have alerted either pilot to the fact that the fuel cutoff switches had been set to CUTOFF?
July 12, 2025, 03:30:00 GMT
permalink Post: 11920143
This is pure speculation but I can envision the following sequence of events that would match the timeline and the little we know from the CVR and sequence of events.
- While PF is concentrated on flying the airplane, PNF moves the switches from RUN to CUTOFF in quick succession (for whatever reason).
- PF doesn't notice that the switches have been moved (again, he is concentrated on flying) but soon perceives the loss of thrust and sees a message on EICAS.
- PF looks down to check throttle position. It takes him a couple seconds to realize that the switches are in CUTOFF position.
- PF asks PNF (and his superior) "Why did you cut off the engines?" (or something similar). PNF anwers that he didn't (a lie, but we don't know if deliberate or just confusion / mental breakdown)
- PF realizes that PNF is in a wrong mental state, and attempts to restart the engines. It takes him a couple of seconds to move both switches because his other hand is on the yoke trying to stabilize the airplane.
- By then the airplane has lost too much energy for a successful recovery. One of the pilots calls MAYDAY because he knows that they are about to crash.
This sequence would match the timeline between the initial fuel cutoff, and when the switches were moved back to run position, and would actually indicate great presence of mind and quick decision from the PF.
Again, this is pure speculation but it would match well with the little information we have.
- While PF is concentrated on flying the airplane, PNF moves the switches from RUN to CUTOFF in quick succession (for whatever reason).
- PF doesn't notice that the switches have been moved (again, he is concentrated on flying) but soon perceives the loss of thrust and sees a message on EICAS.
- PF looks down to check throttle position. It takes him a couple seconds to realize that the switches are in CUTOFF position.
- PF asks PNF (and his superior) "Why did you cut off the engines?" (or something similar). PNF anwers that he didn't (a lie, but we don't know if deliberate or just confusion / mental breakdown)
- PF realizes that PNF is in a wrong mental state, and attempts to restart the engines. It takes him a couple of seconds to move both switches because his other hand is on the yoke trying to stabilize the airplane.
- By then the airplane has lost too much energy for a successful recovery. One of the pilots calls MAYDAY because he knows that they are about to crash.
This sequence would match the timeline between the initial fuel cutoff, and when the switches were moved back to run position, and would actually indicate great presence of mind and quick decision from the PF.
Again, this is pure speculation but it would match well with the little information we have.
July 12, 2025, 07:42:00 GMT
permalink Post: 11920296
Timeline of known events with source attribution from the preliminary report:
08:07:33 ATC: Takeoff clearance
08:07:37 A-SMGCS: Aircraft starts rolling
08:08:33 EAFR: V1 153kts
08:08:35 EAFR: Vr 155kts
08:08:39 EAFR: Gnd-Air mode transition
08:08:42 EAFR: Max IAS 180kts, Eng 1/2 Cutoff switches activate within 1 second of each other
08:08:42 CVR: "Why did you cut off", "I did not" (exact time not specified)
08:08:42 A-SMGCS: RAT deployed (exact time not specified)
08:08:47 EAFR: Both engine N2 below min idle. RAT hyd pwr commences
08:08:52 EAFR: Eng 1 cutoff to RUN
08:08:54 EAFR: APU inlet door opens (auto start logic)
08:08:56 EAFR: Eng 2 cutoff to RUN
08:09:05 ATC: Mayday call
08:09:11 EAFR recording stops
Fuel cutoff switches operated within 1 second of each other suggests to me that the locking mechanism wasn't working as per (SAIB) No. NM-18-33. Any loose item could have accidentally (or not) operated the switches (including hands).
08:07:33 ATC: Takeoff clearance
08:07:37 A-SMGCS: Aircraft starts rolling
08:08:33 EAFR: V1 153kts
08:08:35 EAFR: Vr 155kts
08:08:39 EAFR: Gnd-Air mode transition
08:08:42 EAFR: Max IAS 180kts, Eng 1/2 Cutoff switches activate within 1 second of each other
08:08:42 CVR: "Why did you cut off", "I did not" (exact time not specified)
08:08:42 A-SMGCS: RAT deployed (exact time not specified)
08:08:47 EAFR: Both engine N2 below min idle. RAT hyd pwr commences
08:08:52 EAFR: Eng 1 cutoff to RUN
08:08:54 EAFR: APU inlet door opens (auto start logic)
08:08:56 EAFR: Eng 2 cutoff to RUN
08:09:05 ATC: Mayday call
08:09:11 EAFR recording stops
Fuel cutoff switches operated within 1 second of each other suggests to me that the locking mechanism wasn't working as per (SAIB) No. NM-18-33. Any loose item could have accidentally (or not) operated the switches (including hands).
Last edited by sorvad; 12th July 2025 at 08:03 . Reason: Clarification
July 12, 2025, 08:17:00 GMT
permalink Post: 11920331
Timing of Query Re Cut Off Switches
From the report, there is no indicated time stamp identifying the point when one pilot asked the other "why did you cut off"
This could explain the the assumption that it took ten seconds to reverse the switch positions.
Cut off could have been noticed at any point later than 08:08:42 but before 08:08:52.
This could explain the the assumption that it took ten seconds to reverse the switch positions.
Cut off could have been noticed at any point later than 08:08:42 but before 08:08:52.
July 12, 2025, 11:39:00 GMT
permalink Post: 11920544
Originally Posted by
Viloator
This is a discussion forum, of course there is (and should be!) significant discussion about a bizarre crash of a modern widebody aircraft. There will naturally be speculation and some nonsense but this is a discussion forum and that is to be expected.
Originally Posted by
Firesok
I posited this very thing weeks ago but it was immediately removed by mods.
July 12, 2025, 18:59:00 GMT
permalink Post: 11920753
Earlier today I watched Mentour Pilot's YouTube discussion, one of the things Petter said was "Brain fart of the century" regarding the erroneous selection of cut-off 3 seconds after leaving the ground. Somewhere else I saw this sort of thing described as a "Car keys put in the fridge" event.
I'm also reminded of the Moorgate tube train crash in 1975, no one has ever determined why an experienced driver who had driven the short out and return route 4 times that day suddenly accelerated while bringing his train into a terminus station with a closed tunnel beyond the platform end.
As someone married to a person who suffers with epilepsy, I'm used to short term memory interruption events where my wife will have done something and then not remember doing it 10 seconds later. I suppose such a thing in a pilot is a possibility, a new sufferer may not even realise that they have this kind of condition or even know they have performed an action.
I don't have anything else I can add to this, I read the preliminary report twice and checked every word. It doesn't offer any clear suggestions without expanding on the limited information provided. Undoubtedly the investigators have a lot more information they can examine but it will take time. One thing is that it doesn't mention a positive rate call, in the circumstances that suggests that this wasn't made and was replaced with the "Why did you cut-off?" question.
I note that this crash might have been more survivable with a 15 degree change of heading to the left towards a more open area to the south of the 5 buildings involved, but of course there would be no reason for the crew to have done this or indeed any time to do it.
I'm also reminded of the Moorgate tube train crash in 1975, no one has ever determined why an experienced driver who had driven the short out and return route 4 times that day suddenly accelerated while bringing his train into a terminus station with a closed tunnel beyond the platform end.
As someone married to a person who suffers with epilepsy, I'm used to short term memory interruption events where my wife will have done something and then not remember doing it 10 seconds later. I suppose such a thing in a pilot is a possibility, a new sufferer may not even realise that they have this kind of condition or even know they have performed an action.
I don't have anything else I can add to this, I read the preliminary report twice and checked every word. It doesn't offer any clear suggestions without expanding on the limited information provided. Undoubtedly the investigators have a lot more information they can examine but it will take time. One thing is that it doesn't mention a positive rate call, in the circumstances that suggests that this wasn't made and was replaced with the "Why did you cut-off?" question.
I note that this crash might have been more survivable with a 15 degree change of heading to the left towards a more open area to the south of the 5 buildings involved, but of course there would be no reason for the crew to have done this or indeed any time to do it.
July 12, 2025, 20:12:00 GMT
permalink Post: 11920803
In the case of (2) or (3), would the expected response be "Why did you cutoff"?
I would have thought a pilot would notice the engines spooling down, and comment on that. To immediately jump to the cutoff switches as the cause rather implies something drew attention to the switches.
Then there is a 10+ second gap before the switches are set to run again. I can't think of any good reason why the PNF would have taken so long to correct an accidental or deliberate manipulation of the switches.
I would have thought a pilot would notice the engines spooling down, and comment on that. To immediately jump to the cutoff switches as the cause rather implies something drew attention to the switches.
Then there is a 10+ second gap before the switches are set to run again. I can't think of any good reason why the PNF would have taken so long to correct an accidental or deliberate manipulation of the switches.
The truth will be in what was said after 'I didnt', but that's conspicuously absent from the report.
July 12, 2025, 20:34:00 GMT
permalink Post: 11920817
The accident report indicates that the aircraft had a STAB master caution warning on the previous sector. A maintenance action took place during the turnaround in AMD before the accident flight.
Noting that the two guarded stab cutoff switches are directly adjacent to the two guardedfuel run/cutoff switches at the base of the throttle quadrant ,
Noting that the two guarded stab cutoff switches are directly adjacent to the two guardedfuel run/cutoff switches at the base of the throttle quadrant ,
Since some posters seem focused on the theory that the fuel control switches didn't move - just the electric output did (and as I posted earlier, the FDR only knows electrical states, there is literally no other way for the FDR to monitor the switch position).
So I did a little thought experiment. Uncommanded engine shutdowns (for all causes) are already rare - a 10-6 event. Now, during my 40 year career, I can't remember ever encountering a case where the fuel shutoff was commanded without a corresponding movement of the fuel switch. However in this industry it's a good idea to 'never say never', so let's assume it's happened. It would take something like a hot short to cause it to happen ( moving the voltage from RUN to CUTOFF ) since an open circuit will simply leave the valves where they were. That would put its probability way out there - something like 10-8/hr.
So I did a little thought experiment. Uncommanded engine shutdowns (for all causes) are already rare - a 10-6 event. Now, during my 40 year career, I can't remember ever encountering a case where the fuel shutoff was commanded without a corresponding movement of the fuel switch. However in this industry it's a good idea to 'never say never', so let's assume it's happened. It would take something like a hot short to cause it to happen ( moving the voltage from RUN to CUTOFF ) since an open circuit will simply leave the valves where they were. That would put its probability way out there - something like 10-8/hr.
In the cockpit voice recording, one of the pilots is heard asking the other why did he cutoff.
The other pilot responded that he did not do so
The other pilot responded that he did not do so
I would suggest starting with the maintenence engineer/crew who found 'no fault' after the STAB master caution was investigated immediately prior to this tragic flight. It would not be the first time that 'maintenance' caused an incident...
Also, I urge you all to consider how many accidents have been blamed on 'pilot error' (how convenient when billion-dollar companies are at risk) only for further information to come to light that then exonerates the pilots (these stories don't usually make the front page).
Try to stay open-minded folks. The investigation has a very long way to go.
July 12, 2025, 21:31:00 GMT
permalink Post: 11920849
First, 10 seconds is not a long time. Second, I don't know where you are getting the idea that there was a 10 second gap between the pilots noticing or asking 'why did you cut off' and the switches being reset, because the report doesn't give a timestamp for either exclamation from the pilots. It may well have only been a couple of seconds between them noticing and resetting them, the report simply doesn't give that detail.
The truth will be in what was said after 'I didnt', but that's conspicuously absent from the report.
The truth will be in what was said after 'I didnt', but that's conspicuously absent from the report.
Of course deliberate pilot sabotage has occurred in the past, nobody is disputing that. But personally I'm aware of far more cases of pilot mistakes without malice as the root cause of an accident than of all the confirmed and possible cases of sabotage put together, and I'm sure that there are even more cases of the former that I've never heard about (and I don't mean pilot error in general, I'm referring to things like e.g. taking off with an improper configuration).
I think people are not actually thinking through how the situation would play out IF it was an honest mistake. Ten seconds is no time at all for either pilot to:
- notice the degrading performance (and/or warnings)
- scan the instruments and controls for the problem
- see (on their display and confirm on the pedestal) that fuel has been cut off
- ask the other pilot why they did that (because neither pilot would believe they were the one who did so - that is how action slips work)
- get a response that they did not (again, see above)
- snap out of confusion and actually do something about the situation
Pilots have reacted with far less alacrity in plenty of accidents (even in cases where the day was ultimately saved) and it was not my impression that the aviation industry accused them of criminal intent for it. Surely there is a middle ground between robotic hyper-competence and literal murder? Don't get me wrong, there is a solid chance that it turns out to have been the deliberate murder of hundreds of people. But to me at least it seems extremely uncharitable to confidently declare that that's what happened off a very loose timeline, or to paint people who are considering the possibility of a mistake as just hiding from the truth.