London [UK], July 12: A preliminary report depicted confusion in the cockpit shortly before an Air India jetliner crashed, killing 260 people last month, after the plane's engine fuel cutoff switches almost simultaneously flipped, starving the engines of fuel.
The Boeing 787 Dreamliner bound for London from the Indian city of Ahmedabad immediately began to lose thrust and sink down, according to the report on the world's deadliest aviation accident in a decade released on Saturday by Indian accident investigators.
The report by India's Aircraft Accident Investigation Bureau (AAIB) about the June 12 crash shortly after takeoff raises fresh questions over the position of the critical engines fuel cutoff switches, while suggesting that Boeing and engine maker GE had no apparent responsibility for the accident.
Almost immediately after the plane lifted off the ground, CCTV footage shows a backup energy source called a ram air turbine had deployed, indicating a loss of power from the engines.
In the flight's final moments, one pilot was heard on the cockpit voice recorder asking the other why he cut off the fuel. "The other pilot responded that he did not do so," the report said.
It did not identify which remarks were made by the flight's captain and which by the first officer, nor which pilot transmitted "Mayday, Mayday, Mayday" just before the crash.
The commanding pilot of the Air India plane was Sumeet Sabharwal, 56, who had a total flying experience of 15,638 hours and, according to the Indian government, was also an Air India instructor. His co-pilot was Clive Kunder, 32, who had 3,403 hours of total experience.
The fuel switches had almost simultaneously flipped from run to cutoff just after takeoff. The preliminary report did not say how the switches could have flipped to the cutoff position during the flight.
U.S. aviation safety experts have said a pilot would not be able to accidentally move the fuel switches.
Flipping to cutoff almost immediately cuts the engines.
It is most often used to turn engines off once a plane has arrived at its airport gate and in certain emergency situations, such as an engine fire.
The report does not indicate there was any emergency requiring an engine cutoff.
At the crash site in Ahmedabad, both fuel switches were found in the run position and the report said there had been indications of both engines relighting before the low-altitude crash.
U.S. aviation safety expert Anthony Brickhouse said a key question is why the were switches moved in a way that is inconsistent with normal operations.
"Did they move on their own or did they move because of the pilots?" he asked. "And if they were moved because of a pilot, why?"
Air India acknowledged the report in a statement on the social media site X.
The carrier said it was cooperating with Indian authorities but declined further comment.
India's AAIB, which released the report around 1:30 a.m. IST on Saturday (2000 GMT on Friday), said at this stage of the investigation, there were no recommendations to Boeing 787-8 or GE GEnx-1B engine operators or manufacturers.
Boeing and GE Aerospace did not respond immediately to requests for comment.
Source: Fijian Broadcasting Corporation