Colby Cosh: Cause of Air India Flight 171 crash a mystery of extraordinary urgency

National Post

16-07-2025

On Saturday, the Aircraft Accident Investigation Bureau of India issued a preliminary report into the June 12 crash of Air India Flight 171 in Ahmedabad. The crash was the first-ever fatal accident involving a Boeing 787 Dreamliner. Video of the doomed flight, which was bound for Gatwick Airport in London, England, shows the plane losing altitude just after liftoff despite remaining in level flight with the nose up. Of the 230 passengers, 229 were killed, along with 19 people on the ground at a medical college located 1,500 metres beyond the end of the runway.
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This all adds up to a mystery of extraordinary urgency — but the terse investigation bureau report reveals a clear proximate cause for the disaster. The plane's data recorder shows that the plane took off, and about three seconds later, the fuel cutoff switches to both engines were activated — independently and about one second apart. The engines, suddenly starved of fuel, began to lose thrust.
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The report cites the cockpit voice recording, without providing a full transcription: 'one of the pilots is heard asking the other why did he cutoff. The other pilot responded that he did not do so.' The switches were restored to their proper 'RUN' setting about 10 seconds after being engaged, and the engines kicked into an automatic in-flight recovery mode, but it was too late. A 'MAYDAY' call was issued from the cockpit a few seconds before impact.
Air India has a good safety record, and both pilots had oodles of experience. The fuel cutoff switches in all wide-body aircraft are, as you would expect, located far from the ordinary flight controls. Moreover, they cannot, in the ordinary course of operation, be engaged inadvertently. You have to pull up a locking bracket to activate the switches — each switch has its own independent lock — and the switches themselves are spring-loaded in case the bracket is in the unlocked position. Cutting off fuel to both engines immediately after takeoff is a suicidal action, as the crash itself demonstrates.
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Could some mechanical defect still have been responsible for the accident? Fleets that operate Dreamliners are checking, and the U.S. Federal Aviation Administration (FAA) sent out a circular in 2018 warning that some fuel control switches in Boeing 737s had been installed with the locking mechanisms in the disengaged setting. But Western aviation experts find themselves at a loss to imagine why or how both cutoff switches could have been activated inadvertently (one after the other) — and the inevitable political firestorm is already whirling. One group representing Indian pilots is criticizing the 'reckless and unfounded insinuation of pilot suicide' by observers, and another is directly denouncing the report, warning that 'we feel the investigation is being driven in a direction presuming the guilt of pilots.'
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Unfortunately, murder-suicides by pilots are hardly unknown to aviation, although they are inherently hard to establish in technical investigations. The involvement of impulsive humans in aircraft command may in fact be one of the largest remaining dangers in ordinary commercial aviation, although the possibility of murder-suicide is still contested in cases like the vanishing of Malaysia Airlines Flight 370 and even, rather absurdly, the crash of EgyptAir 990.