The preliminary finding gives investigators a new line of inquiry as they study a crash that killed all but one of the plane’s passengers.

One of the engines of the Air India plane that crashed last week was new, while the other was not due for servicing until December, the airline's chairman has said. In an interview with an Indian news channel, N Chandrasekaran said that both engines of the aircraft had "clean" histories.

The London-bound Boeing 787-8 Dreamliner with 242 people on board crashed into a medical hostel complex in Ahmedabad on June 12.