Investigators of the Ministry of Civil Aviation, who analyzed voice recordings on the cockpit, found that 12 -year -old fuel switches Boeing 787 Dreamliner moved from “run” to a “limited” position in one second, leading to sudden loss of energy, led to an accident from June 12.
One pilot can be heard that he asks the other, “Why did you cut off?” To which the other replied, “I didn’t do it.” The last conversation between pilots suggests either a failure or an involuntary action.
Mint explains what turned out in the cockpit of the London aircraft.
What happened after takeoff?
The flight received a take -off take -off at 13:37 ist. According to data on the flight recorder, the aircraft exceeded the take -off decision and reached the speed of 153 knots at 13:39. The aircraft reached the maximum recorded flight speed of 180 knots and began to gain height. After a few seconds, the fuel switches of both engines 1 and 2 moved from the “run” position to the “marginal” position in 01 seconds, killing the fuel supply.
What did the pilots do?
In voice recordings obtained from a black cabinet, one of the pilots is heard to ask the other why he cut off the fuel supply. The second pilot replied that he did not. At 13:39, one of the pilots handed over the calling a’mayday to control the air traffic, but there was no answer.
The plane began to lose altitude before it exceeded the perimeter wall of the airport and came across BJ Medical College.
CCTV airport shots have shown that RAM air turbine (rat)-energy source in the case of complete or partial loss of primary energy systems-not immediately after lifting. The rat uses air flow to generate energy to maintain essential aircraft systems running.
Did the pilots try to restart the engines?
Fuel switch 1 Motor 1 passed from “limit” to “run” around 13:38. In four seconds, the engine switch 2 also switched from “marginal” to “run”.
The data showed that the engine core slowed down, stopped, turned and began to recover. The engine 2 was able to reappear, but could not stop slowing speed. The data record stopped at 13:39.
AAIB said that when fuel control switches move from “marginal” to “run”, while the aircraft is in flight, full authority engine with two engine control (FADEC) automatically manages the ignition sequence and fuel introduction. FADEC is a digital electronic system that manages the power of the aircraft engine.
Is there a advice for using fuel control switches?
In 2018, the US Aviation Authority, Federal Aviation Administration (FAA), issued a special bulletin for information about flight capacity (SAIB) in 2018 about the possible release of the fuel switch lock function. SAIB was published on the basis of 737 Max Aircraft reports that the control switches were installed with the released lock function.
Did Air India follow the FAA?
Air India told investigators that the design of fuel switches is similar in all Boeing aircraft and the same has been mounted in VT-ANB. According to Air India, the proposed inspection was not carried out because SAIB was “counseling and was not compulsory”.
AAIB maintenance record revealed that the throttle control module was replaced in 2019 and 2023 on VT-ANB (Dreamliner). However, the reason for the replacement was not associated with fuel switches. Since 2023, no defect in fuel switches on VT-ANB has been reported.
Was the plane well maintained?
According to AAIB, all relevant flight capacity and warning services were met on aircraft and engines.
The last inspection of the main line maintenance according to the aircraft maintenance program was carried out as planned. Another main inspection was due to the plane in December 2025.
The left engine was installed 1 May 2025 and the right engine on March 26, 2025.
What do experts say?
Mark Martin, the CEO of Martin Consulting, said no pilot would treat switches in the central part of the cockpit when all attention focused on the instruments for front flights located before pilots, during take -off and landing.
He added that the 787 Dreamliner is a comprehensively digitally controlled and software aircraft that constantly needs repair and system updates. If fuel switches move to “marginal”, the cause of this trigger should be created.
Amit Singh, CEO of Safety Matters Foundation, raised questions about the accuracy of the timeline and interpretation of data at the microblogging site, X.
He stressed that the rat was deployed while the aircraft was hardly in the air. In Boeing 787, a rat takes 3-5 seconds after the engine failure fully deployment.
He suggested that the engine failure occur within a few seconds of the elevator.
What will happen now?
Another probe is conducted by Sanjay Kumar Singh of Aaib. The investigation is supported by FAA, the US National Transport Safety Council, the British Civil Aviation Authority, UK NTSB and Boeing.
The team will check and explore other evidence, records and information required from the parties.
At this stage, there are no recommended actions for engine and engine manufacturers Genx-1B B787-8 and/or GE Genx-1B AAIB.
(Tagstotranslate) Air India Flight 171 (T) Boeing 787 Dreamliner (T) Fuel Control Switches (T) Cockpit Voice Records (T) AAIB Investigation (T) Air India Crash (T)
