Captain Kishore Chinta, a former investigator with India's Aircraft Accident Investigation Bureau (AAIB), calls this "the rarest of the rare" crashes - a controlled flight into terrain just 30 seconds after take-off. "To my knowledge, nothing quite like this has ever happened," he told the BBC.

Investors and the wider public are looking for answers after Thursday’s crash of an Air India 787 jet. Both of the plane’s black boxes have been recovered.

Investigators in India are studying the black boxes of a Boeing 787 Dreamliner after recovering them from the aircraft wreckage to ascertain the cause of last week’s plane crash that left at least 270