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sixgee
July 10, 2025, 09:59:00 GMT permalink Post: 11918893 |
Ex 787 pilot here, I can confirm that the excerpt from the FCTM above is correct, and also confirm that the QRH memory items for Dual Engine Fail/Stall are:
Condition: Engine speed for both engines is below idle Fuel Control Switches (both) \x85 CUTOFF then RUN RAM AIR TURBINE switch \x85 Push and hold for1 second |
TBL Warrior
July 10, 2025, 11:14:00 GMT permalink Post: 11918946 |
Ex 787 pilot here, I can confirm that the excerpt from the FCTM above is correct, and also confirm that the QRH memory items for Dual Engine Fail/Stall are:
Condition: Engine speed for both engines is below idle Fuel Control Switches (both) \x85 CUTOFF then RUN RAM AIR TURBINE switch \x85 Push and hold for1 second ![]() |
paulross
July 10, 2025, 13:04:00 GMT permalink Post: 11919015 |
AI171 Thread by Subject
I have rebuilt the site that organises this thread by subject here:
https://paulross.github.io/pprune-th...171/index.html
Changes:
Raise issues here https://github.com/paulross/pprune-threads/issues or PM me. |
Musician
July 11, 2025, 23:26:00 GMT permalink Post: 11919991 |
Speculations laid to rest
I am going by the list in the excellent post here:
Air India Ahmedabad accident 12th June 2025 Part 2
Anyway, here goes: A. Misconfiguration or wrong takeoff data — OUT : 5 tons under MTOW, flaps 5, takeoff roll uneventful B. Flaps retracted post-takeoff instead of gear — OUT : flaps 5 still set at crash C. Low-altitude capture — OUT : throttle was at take-off thrust the whole time D. Loss of both engines at or shortly after rotation — IN: confirmed to have occurred 3-4 seconds after liftoff I. Bird strike/FOD — OUT II.Fuel-related 1. Loss of electric fuel pumps — OUT 2. Fuel contamination — as good as OUT , but lab work is ongoing 3. Vapour lock — OUT III. Improper maintenance — mostly OUT , switches might have been defective IV. Large-scale electrical fault (e.g. due to water in E&E bay) — OUT . This would have been obvious from the flight recorder. V. Shutdown of engines by TCMA — OUT . Conditions not met (not on ground, throttle not at idle) 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 — OUT from CVR 2. No indications whatsoever of an intentional shutdown for nefarious reasons — IN but unsupported 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. — IN Read the previous post to this by 9 lives and reconsider VII.1 Senior Pilot 2. Spilled drink leading to short in the wiring — IN (barely) , 8 separate switch contacts must be affected in just the right way If you never supported any of the theories that are now out, pat yourself on the back! ![]() Last edited by Senior Pilot; 12th July 2025 at 03:40 . Reason: added comment |
Tobin
July 12, 2025, 02:48:00 GMT permalink Post: 11920120 |
The report proved that occams razor was right. Fuel switches acted which was the simplest explanation. And occams razor will not allow for a 15000h line check captain as PM to need over 10 seconds to reset fuel switches while both engines spooled down from TO thrust to sub idle within 5 seconds.
I'm not ready to accept the time-line. My FO's were not as highly trained and the aircraft much simpler, but I'd track what they were doing every second until I'd got comfortable airspace under me. Reaching out and stopping the engines? Asking why? What world are they living in?
WTFH!!!!!? followed by the switches being back on. I really don't think I was that much different to my colleagues - they'd darn soon react to fairly modest mistakes, let alone chopping the fuel. Having read both previous threads, I recall there were easily a dozen or two comments that claimed that a pilot's hands should be nowhere near the thrust levers or fuel switches until 400' AGL, no matter if an engine is out or on fire. (This was in response to suspicions that one of the pilots has prematurely actioned the engine-out memory items.) A similar number of comments emphasized that the pilots should calmly verify any engine-related issues before taking any action that might affect thrust, and that their training emphasizes this. You can't have it both ways. Either pilots are expected to react instantly (and cause mistakes like shutting off both engines by misreading the situation) or they're expected to take a moment to assess an unexpected failure before acting (in which case 10 seconds is still pretty darn fast). I lean toward the latter of those. |
Kirks gusset
July 14, 2025, 11:50:00 GMT permalink Post: 11922122 |
Pilot error.. flown 777 and 787 for years now, these fuel control switches don't bounce about and it takes a positive action to move them to cut off.. FO was PF and Captain probably got confused by throttles rolling back and started double loss of thrust memory actions... but at low altitude? what on earth ? Thrust levers were "fully forward " according to report so some attempt to squeeze the juice... of course if it was something more sinister with no audio on the CVR we will never know.. sadly
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appruser
July 15, 2025, 21:55:00 GMT permalink Post: 11923297 |
In my opinion, not enough attention is being paid to why the Pilot Monitoring might have *had to* execute the memory items for dual-engine failure. |
Mrshed
July 15, 2025, 21:57:00 GMT permalink Post: 11923299 |
Other than the report stating (by implication of IAS etc) no issue with thrust until the switches were moved, as well as the CVR exchange shared makes basically no sense in that scenario.
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galaxy flyer
July 15, 2025, 22:58:00 GMT permalink Post: 11923333 |
Likely because the FDR readout showed the engines at the appropriate takeoff thrust, then the switches move, takeoff thrust goes away. Switches move back to RUN and the quick restart begins.
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