Flaps are retractable surfaces on the trailing edge of wings. An aircraft, during the take-off and landing phases when its speed is slow, requires extra ‘lift’

Safety experts said investigators would be looking at why and how the plane started descending during its take off.

At least 290 people have died after an Air India plane crashed shortly after take off from Ahmedabad airport in India on Thursday, a senior doctor at the Ahmedabad Civil Hospital, where a majority of the dead and injured people were taken, told CNN.