Posts about: "Memory Items" [Posts: 49 Pages: 3]

sixgee
July 10, 2025, 09:59:00 GMT
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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
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Post: 11918946
Originally Posted by sixgee
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
Here ya go

paulross
July 10, 2025, 13:04:00 GMT
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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:
  • Built the thread up to July 10, 2025, 12:31:00
  • Add subjects: Relight, 51 Day Issue, Fuel Cutoff Switches (detent), ICAO, Fuel Cutoff Switches, Memory Items, Annex 13, Simulation Scenarios.
  • Various technical fixes should give a better/more accurate presentation.
Project is here: https://github.com/paulross/pprune-threads
Raise issues here https://github.com/paulross/pprune-threads/issues or PM me.
Musician
July 11, 2025, 23:26:00 GMT
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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
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Post: 11920120
Originally Posted by EDLB
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.
Originally Posted by Loose rivets
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.
Both of the comments above imply that the 10 second wait to set the switches back to RUN is excessive and inexplicable for an "experienced" pilot.

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
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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
appruser
July 15, 2025, 21:55:00 GMT
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Post: 11923297
Originally Posted by Mrshed
Simply calls for both fuel switches to be moved to CUTOFF then back to RUN.
Literally what the Preliminary Report says happened. Even the Pilots' exchange fits within this context.

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
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Post: 11923299
Originally Posted by appruser
Literally what the Preliminary Report says happened. Even the Pilots' exchange fits within this context.

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.

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.
galaxy flyer
July 15, 2025, 22:58:00 GMT
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Post: 11923333
Originally Posted by appruser
Literally what the Preliminary Report says happened. Even the Pilots' exchange fits within this context.

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.
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.