There are other scenarios
Air India Flight 171 crashed shortly after takeoff, killing all but one onboard and many people on the ground outside the airport perimeter. It is now widely understood that a preliminary report, based on information gleaned from the recovered voice and data recorders, and from simulations to test out certain scenarios, that the two fuel switches (for left and right engines) in the cockpit were turned off, shutting down the engines and deploying the RAT.
Observers say that the RAT (Ram Air Turbine, which provides emergency auxiliary power) deployed only seconds after the aircraft lifted off from the runway. The RAT deployed between 4 and 5 seconds after the aircraft cleared the runway. It would have taken another 5 seconds or more for the RAT to generate electricity. We don’t know if the cockpit went blank from lack of power in this 10 to 15 second interval. The aircraft has lithium batteries (a source of trouble in the past): but in an electrical failure you don’t know if power from the batteries would have been available.
Shutting off fuel would shut down the engines and deploy the RAT.
The Boeing 787 Dreamliner uses two main lithium-ion batteries: a main battery located in the forward electronics bay and an auxiliary power unit (APU) battery in the aft electronics bay. These batteries serve several critical functions, including starting the engines or APU, providing backup power for critical systems, and supporting ground operations.’
The voice conversations in the cockpit have not been released either in original form or transcribed. Whether they will be is unknown.
Some suggest that switching off the fuel for both engines could have been a suicide by pilot (or copilot). No information about the personal circumstances of either pilot has been made public, if in fact such information exists. There are no news reports that either pilot was having personal problems (a topic that was considered in the crash of EgyptAir 990 in 1999, Germanwings Flight 9525 in 2015 and Malaysian Airline flight MU-370 in 2017).
[I need to revise the above paragraph. The Wall Street Journal reports that the pilot asked the copilot why he turned off an engine switches, and the copilot responded that he did not. The Journal, citing the written report, adds nothing more, so we don’t know if the pilot switched them back, or even if there was time to do so. This interaction strengthen the case that the crash was caused by the action of the crew and not a problem with the aircraft.]
There are procedures to turn the fuel switches off and back on in case of a dual engine failure. That would have happened if there was some sort of engine emergency and a response by the pilots to flip the switches back and forth. Such a procedure would have been called out and heard on the voice recorder. We will have to wait to see what the investigators say on that score (if anything).
We don’t know if there was any cockpit conversation about the fuel switches. If either the pilot or copilot shut them off, the other could switch them back on. Apparently that never happened.
There is an issue with timing. If the RAT deployed so quickly, indicating an electrical and hydraulic failure, the pilots may have tried to use the fuel switches as an emergency procedure to get the engines going again, a little like resetting a circuit breaker in a home or office power bloc. If that scenario is the right one, then they had time to turn the switches off, but it was too late to turn them back on as the plane crashed.
If this scenario is right, then the switches are not the cause of the crash, but the consequence of a massive electrical/hydraulic failure that killed the engines.
Here the timeline is critical.
The main point is that the fuel switches may have been a consequence of electrical failures and not the cause of the crash, although the investigation allegedly points in the opposite direction. From what we currently know, the preliminary report does not reach any conclusion on the cause of the crash.
In my earlier article I stated that the most likely cause was a massive electrical and hydraulic failure. That scenario still makes the most sense, given the time lines that we know so far. However, the information from the voice recorder points in the direction of a crash by suicide and not a massive electrical and hydraulic failure.
Below is part of the preliminary accident report:
Preliminary Report Accident involving Air India’s B787-8 aircraft bearing registration VT-ANB Ahmedabad on 12 June 2025. Key Information (Summary) –
1. The flap handle assembly was found to be firmly seated in the 5-degree flap position, consistent with a normal takeoff setting.
2. The landing gear lever was in “DOWN” position.
3. The thrust levers remained forward (takeoff thrust) until the impact.
4. Both fuel control switch were found in the “RUN” position
5. The reverser levers were bent but were in the “stowed” position. The wiring from the TO/GA switches and autothrottle disconnect switches were visible, but heavily damaged.
6. Fuel samples taken from the bowsers and tanks used to refuel the aircraft were tested at the DGCA’s Lab and found satisfactory.
7. 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.
8. 08:08:47 RAT (Ram Air Turbine) hydraulic pump began supplying hydraulic power
9. 08:08:52 Engine 1 fuel cutoff switch transitioned from CUTOFF to RUN
10. 08:08:56 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. (ie both engines were put back into “run” mode, however failed to reignite in time.)
11. 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.
12. 08:09:05 pilots transmitted “MAYDAY MAYDAY MAYDAY”
13. 8:09:11 Recording ends
Pilots Information –
*Captain 56 ATPL Licence – Total Hours 15638, on B787 8596, Command Hours Total on B787 8260
*Co Pilot 32 CPL Licence – Total Hours 3403, on B787 1128, Command Hours Total on B787 0
Aircraft Information –
Total Aircraft Hours 41868 . The last major line maintenance was L1-1and L1-2 check carried out at 38504 Hrs D Check was due on the aircraft in Dec 2025.
The LH Engine Total Engine Hours/Cycles 27791/4298 with ESN956174 was installed on 01 May 2025 and the RH Engine Total Engine Hours / Cycles 33439/ 6202 with ESN956235 was installed on the aircraft on 26 Mar 2025.
https://tinyurl.com/REPORT-AIR-INDIA
Source: author’s blog
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