AirAsia plane crashed after pilots turned off autopilot, say investigators
- Plane had problems with rudder system 23 times in the 12 months prior to the crash
- The Airbus A320 soared from 32,000 feet to 37,400 feet in 30 seconds before it stalled
The AirAsia plane that crashed into the Java sea in December last year killing 162 people was caused by the pilots' response to a crack in the soldering on the rudder control system, Indonesian investigators have said.
After the pilots received four warning alerts, they responded by resetting the control system, which disengaged the autopilot causing them to lose control of the plane.
The National Transportation Safety Committee (NTSC) announced on Tuesday that an analysis of Flight 8501's data recorder showed that the Airbus A320 had problems with its rudder control system less than halfway into a two-hour flight from the Indonesian city of Surabaya and Singapore on December 28.
“Subsequent flight crew action resulted in inability to control the aircraft … causing the aircraft to depart from the normal flight envelope and enter a prolonged stall condition that was beyond the capability of the flight crew to recover,” the NTSC said in a statement.
The black box data recorder showed the plane soared from 32,000 feet to 37,400 feet in 30 seconds before it stalled.
Investigators said co-pilot Remi Plesel was at the controls in the moments before it crashed, rather than the more experienced Captain Iriyanto.
Aircraft maintenance records show the plane had problems with its rudder system 23 times in the 12 months prior to the crash.
Investigators said there was a failure to "identify repetitive defects and analyse their consequences".
The final report, which has been a year-long investigation, said bad weather conditions did not play a role in the accident and no distress signal was received.
The airline has not yet commented on the findings.