Posts about: "Takeoff Roll" [Posts: 65 Pages: 4]

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!

Not on the take-off roll. It was 3 seconds after liftoff.

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?

You can generally sort out the voices based on the earlier chatter, pre-flight and during takeoff roll. This flight was short enough to capture all of that.

Dani,
I’d be willing to wager $10,000 to any 787 Pilot who can move the Fuel Control Switch to rest exactly on the tip of the “nub” separating the two sides of the locking mechanism…I’d bet it would take quite some time to manipulate it to get it to rest on this rounded tip. I’d also throw in an extra $10,000 to any pilot who can do this for both switches, and not draw the attention of the other pilot as they manipulate the switch into this impossible position. Then, there’s the problem of taxiiing so smooooooothly that the 2 switches don’t fall back off this pinpoint balanced position, let alone they stay in this position during the takeoff roll.

I did fly a sim session once with a pilot who exhibited signs of incompetence. It was a practice sim after he had failed a checkride. He reached across my head and tried to shut off a hydraulic system as he read the checklist for a Pack malfunction. The Pack switches were on his side of the overhead panel! The training Instructor attributed his confusion to the fact that he didn’t fly very much. Turned out he had “Early onset of Alzheimer’s “. Could this be a possibility here?