Preliminary findings into last month’s Air India plane crash suggest the aircraft’s fuel control switches were turned off, causing a loss of engine thrust shortly after takeoff.

An official report on the world’s deadliest aviation accident in a decade, seen by CNN, has answered one key question – but raised others.

The probe into last month's crash of an Air India plane in Ahmedabad is far from over and it is unwise to jump to any premature conclusions, airline CEO Campbell Wilson said in an internal memo on Monday (July 14) after the release of a preliminary report by investigators.