Soerjanto Tjahjono (C), head of Indonesia's National Transportation Safety Committee, speaks during a press conference in Jakarta, Indonesia, Dec. 1, 2015. (Xinhua/Zulkarnain)
Indonesian investigators on Tuesday said that crew errors and a fault with the rudder control system were the major causes of the crash of an AirAsia jet in December last year that killed all 162 people on board.
An analysis of the data recorder of flight QZ8501 showed that when receiving repeated warnings of the faulty component, pilots of the plane tried to reset a computer system, which caused the autopilot to disengage, Nurcahyo Utomo, one of the investigators from the National Transport Safety Committee (KNKT) said.
"Subsequent flight crew action resulted in inability to control the plane," a statement from KNKT said on Tuesday.
Marjono Siswosuwarno, head of the investigators at KNKT, said there were no indications that the weather had affected the aircraft.
Nurcahyo said that the maintenance system at that time failed to detect repeated problems of the plane.
"In the last 12 months problems with the rudder system have been reported 23 times," he said.
The KNKT recommended that Airbus, the producer of the plane, obligate all users of its products to conduct training for pilots on how to recover plane during such emergencies, he said.
The committee also advised that the Federation Aviation Administration (FAA) and the European Aviation Safety Administration (EASA) apply the program of controlling plane during emergencies, Nurcahyo said.
AirAsia flight QZ8501 vanished from radar screens on Dec. 28, 2014 en route from Indonesia's second biggest city Surabaya to Singapore. All 162 people aboard were killed.
