SJ-182 Crash Highlights Throttle Failure and Crew Error

 - November 10, 2022, 10:27 AM
Swirijaya Air's Boeing 737-500 crashed soon after takeoff from Indonesia on January 9, 2021, resulting in the loss of all 62 people on board. (Photo: Flickr Creative Commons)

A malfunctioning automated engine throttle system that pilots failed to adequately monitor was highlighted as a primary cause of the January 2021 crash of Sriwijaya Air’s Flight SJ-182, according to a final report published on Thursday by Indonesia’s KNKT air accident investigation agency. All 62 people on board the Boeing 737-500 were killed when the airliner crashed into the Java Sea within five minutes of taking off from Jakarta.

According to the final accident report, maintenance logs showed 65 instances since 2013 of unresolved technical problems with the autothrottle that controlled the narrowbody’s CFM56 turbofans. KNKT officials indicated that pilots could have done more to monitor errors in the engine parameters, thrust lever settings, and the roll angle of the aircraft, which rolled more than 45 degrees to the left after the autopilot disengaged at around 10,700 feet.

Analysis of the cockpit voice recorder established that the first officer had tried to initiate an upset recovery procedure. However, the report did not state what had subsequently transpired, partly because the captain’s voice recording channel was not working.

Neither Sriwijaya Air nor Boeing has issued a response to the accident report. Engine maker CFM International told AIN that it did not manufacture the autothrottle for the engines. The initial accident response included participation by the FAA, the U.S. National Transportation Safety Board, the Singapore Transport Safety Investigation Bureau, Boeing, and CFM partner GE Aviation.

The Indonesian airline has suffered five hull loss accidents. Additionally, in 2008, one of its Boeing 737-200s overran the runway at Sultan Thaha Airport at Jambi in Indonesia, killing one person on board, and the carrier has had three other runway excursions.