AirAsia crash caused by faulty part and subsequent crew actions

A faulty part and subsequent actions by the crew have been cited by Indonesia’s national transport safety committee as the cause of the AirAsia crash in December 2014.

The report, which was released Tuesday morning UK time, said a number of factors contributed to the crash which killed all 162 people aboard the Airbus A320 aircraft.

Investigators said that a cracked solder joint led to the failure of the Rudder Travel Limiter Unit (RTLU) four times during the flight.

In the first three instances the crew followed procedures but on the fourth alert, investigators said data showed the flight computer’s circuit breakers being reset and resulting in an "electrical interruption."

That caused the autopilot to disengage and resulted in the aircraft rolling to an exceedingly steep 54 degree angle of bank turn.

“Subsequent flight crew action leading to inability to control the aircraft in the Alternate Law resulted in the aircraft departing from the normal flight envelope and entering prolonged stall condition that was beyond the capability of the flight crew to recover."

It wasn’t the first time the aircraft had issues with the RTLU.

Maintenance records showed there had been 23 RTLU problems from January 2014 to 27 December 2014.