Reports say the pilot of a plane that crashed in Nepal last March had an emotional breakdown.
The flight carrying 71 people from Dhaka in Bangladesh caught fire as it landed in Kathmandu, killing 51 people.
It was initially thought that poor communication with air traffic control may have to be blamed.
But investigators now say the pilot was ranting to crew members and even smoking in the cockpit, due to stress.
The 52-year-old pilot was released from the Bangladeshi Air Force in 1993 because of depression but was later declared fit to fly civilian aircraft.