The mystery surrounding the June 12 Air India crash — the worst disaster involving an Indian airline — has deepened further with the chilling discovery that fuel supply to both the engines of the ill-fated flight was cut off for a few seconds after it took off from Ahmedabad airport. According to a preliminary report released by the Aircraft Accident Investigation Bureau (AAIB), the Boeing 787 Dreamliner’s fuel control switches shut down within a second of each other, starving the engines of fuel and triggering total power loss. This raises several unsettling questions about what really happened in the cockpit of the doomed flight. The preliminary report says the fuel control switches for both engines were shifted from ‘RUN’ to ‘CUTOFF’, resulting in an immediate loss of altitude. Since these switches are designed to operate only manually, the question is, why would any sane pilot deliberately operate the fuel cut-off switches right after take-off? The flight crashed outside the airport perimeter 32 seconds after take-off, killing 241 of the 242 people on board and 19 people on the ground. The most critical unknown is what led to both engines shutting down. The pilots denied triggering the shutdown — as per the cockpit voice recorder data — and there is no evidence of bird strike, sabotage, or fuel contamination so far. The 15-page report provides a detailed timeline of the aircraft’s final minutes. But even with flight data, cockpit recordings, and engine analysis underway, investigators have yet to determine why the fuel cut-off switches for both engines moved to “CUTOFF” in-flight, one after the other, and without any known command.
It would be premature to put the entire blame on pilot error for the tragedy. A detailed investigation alone will bring out the facts. The preliminary report does not explain whether this was a mechanical failure, an electrical issue, a design fault or a software anomaly. Basically, the preliminary report does not reveal how the switch could have flipped to the cut-off position. Fuel switches regulate fuel flow to the aircraft’s engine. Experts say that the movement of these critical switches have to be deliberate actions and their accidental movement is next to impossible. The switches have brackets on either side to protect them. Additionally, there is a stop lock mechanism that requires the pilots to lift the switch before moving it from either of its positions — RUN and CUTOFF — to the other. These switches are usually moved only when the aircraft is on the ground — to start the engines before departure and to shut them down after landing. They cannot be physically moved by electrical signals or the plane’s avionics. The investigators are still reviewing cockpit actions, system inputs, and procedural adherence in the minutes before the crash. Furthermore, the flight data is still under analysis, and additional information from Boeing and GE is being sought.