Indonesia investigators focus on engine control in Boeing crash

Bloomberg

The investigation into last month’s Sriwijaya Air crash in Indonesia is focusing on the carrier’s maintenance and training procedures as well as the engine-control system of the Boeing Co 737-500 jet.
While Indonesia’s National Transportation Safety Committee (NTSC) is still trying to determine the exact cause of the disaster, lead investigator Nurcahyo Utomo said at a media briefing on Wednesday that the left engine throttle lever was trimming back the power output while the right lever remained constant just before the 26-year-old jet plunged into the sea.
“Both auto throttles were experiencing anomalies,” said Utomo, a trained pilot. “The left one rolled back too far while the right one was not moving at all and appeared to be stuck. We don’t know which one is malfunctioning, we are still trying to find out.”
A person familiar with the investigation told Bloomberg News last month that a malfunctioning automatic throttle was being considered as a reason for the pilots losing control by producing more thrust in one of the
two engines.
The device had been having problems on previous flights, according to the NTSC but those issues had been rectified and the aircraft had no deferred maintenance items on the day of the crash.
Unequal thrust can cause a plane to roll onto its side and descend abruptly. Utomo said pilots should still be able to control the aircraft even without one engine.
Boeing said in a statement that its technical experts “continue to assist with the investigation and we will provide support needed during this difficult time.” A representative for Sriwijaya Air didn’t immediately respond to a request for comment.
If some part of the jet wasn’t functioning properly due to a technical problem, it could deal another blow to the US manufacturing giant as it emerges from the global grounding of its 737 Max following two other fatal crashes.
Sriwijaya Air Flight 182 crashed into the Java Sea four minutes after takeoff from Jakarta’s main airport on
January 9, killing all 62 people on board.
Searchers retrieved the flight-data recorder from the jet, but the memory module of the cockpit-voice recorder still hasn’t been found.