Authorities released the cause of the Air India crash in their preliminary report, following an investigation. The London-bound flight from Ahmedabad crashed moments into the June 12 flight. Only one passenger of the 242 passengers and flight crew survived.

The London-bound plane had barely left the runway at Ahmedabad airport before it careened back to earth. Everyone on board was killed, except for one passenger.

A focus on the fuel switches in a preliminary assessment raised questions about the pilots’ actions, but much is still unknown about Flight 171.