The Indonesian National Transportation Safety Committee (NTSC) have said a faulty component was a key factor in the crash of an Indonesia AirAsia operated A320-200 in December 2014 which resulted in the death of 162 people.
A report into the incident said Flight QZ8501, which was 40 minutes into its flight from Surabaya to Singapore before contact was lost, was downed following a series of events which began with a fault in the connected circuitry in its rudder warning systems.
This led to its crew attempting to reset the computer system which then caused the accidental disabling of the aircraft’s autopilot function.
The NTSC said the aircraft then entered "a prolonged stall condition that was beyond the capability of the flight crew to recover” which resulted in the crash.
The report also said maintenance teams had been aware of the problem as it occurred 23 times in 2014, and resetting the system was one of a few methods used to rectify it.