Investigation Report Indicates Human Factor Behind Air Asia Crash

medcom.id, Jakarta: Investigation report made by National Transportation Safety Committee (KNKT) indicates human factor has big influence on the crash of AirAsia QZ8501 last year.

 

KNKT in the press conference today (12/12015) revealed it found repetitive faults in the plane's rudder travel limiter unit (RTLU). The same fault occurred four times during the flight before the crash.

 

Flight data recorder (FDR) showed pilot solved the first three faults according to the rule. However in the fourth fault, FDR recorded different signatures indicating the plane's flight augmentation computer (FAC) being reset resulting in electrical interruption in the equipment.

 

KNKT Chief Soerjanto Tjahjono said his institution suspected a person reset the FAC by unplugged and then plugged the FAC's circuit breaker. 

 

"If the FAC's circuit breaker is off by technical reason like short circuit, the FAC will not reset. It will continue to be off," said Soerjanto after the press conference.

 

The problem in the FAC caused the auto-pilot and the auto-thrust disengaged. The rudder moved two degrees which made the plane rolled.

 

The pilot briefly suceeded to control the plane but then it was pulling up as high as 48 degrees. The plane then stalled and the pilot cannot recover until it crashed.

 

Soerjanto said analysis showed there was miscommunication between pilot, Captain Iriyanto, and co-pilot, Remi Emmanuel Plesel, causing the plane to pull up. The pilot said to the co-pilot to pull down rather than push down which made the co-pilot pulled his stick. The analysis showed every time the pilot ordered pull down the plan was pulled up. "The captain said pull down to the co-pilot. He should said push down," Soerjanto explained.

 

KNKT explained pilot and co-pilot sticks in the Airbus plane are not connected. So the pilot did not aware about what happened.

 

During the flight, Plesel was the flying pilot while Captain Iriyanto acted as the monitoring pilot. When the plane was rolling, Captain Iriyanto tried to take the lead.

 

Although human factor has big influence in the crash. KNKT refused to confirm that the crash happened because of human error.

 

"We don't want to blame someone. This investigation was held to prevent future crash," Soerjanto said.

 

KNKT finished the investigation in 11 months. AirAsia Qz8501 crashed in Sea Java in the journey from Surabaya to Singapore in 28 December killing all passengers and crew.

(WAH)