The Indian Aircraft Accident Investigation Bureau report said both pilots were confused about the fuel control switches being in the"off" position instead of "on", which caused the engine to lose thrust shortly after takeoff.

The report said the flight from takeoff to the crash lasted about half a minute. As the aircraft reached its maximum recorded speed,"the fuel cut-off switches for the first engine and the second engine went from the 'Operating' position to the 'Disabled' position one after the other within a second," the report said, without specifying how the switches could have been switched to the off position during the flight.

The movement of fuel control switches enables and disables the fuel supply to the aircraft's engines.

The report said the switches were switched back to the operating position, but the plane was unable to pick up power quickly enough to stop the descent after the plane began to lose altitude.

The initial report stated that there was confusion in the cockpit at the time of the accident, with one pilot asking the other why he had shut off the fuel supply, while the other denied having done so.

The report does not make any recommendations to Boeing. Air India, which has 33 Dreamliners in its fleet, is cooperating with the investigation and has been ordered by Indian authorities to conduct a thorough inspection of its entire Boeing 787 Dreamliner fleet.

An Air India Boeing 787-8 Dreamliner crashed on June 12 in Ahmedabad, killing at least 260 people, including 19 on the ground. Only one passenger survived the crash, one of India's worst aviation disasters.

There were 230 passengers on board the plane - 169 Indian citizens, 53 British citizens, seven Portuguese citizens and a Canadian citizen - as well as 12 crew members.