Indonesia’s National Transportation Safety Committee is investigating whether a problem with the automatic throttle system, which controls engine power, contributed to the Jan. 9 Sriwijaya Air crash that killed all 62 people on board, an official said Friday.
Investigator Nurcayho Utomo said a problem with the Boeing 737-500’s automatic acceleration system was reported following a flight a few days earlier, Reuters reviewed.
“There was a report of malfunction in the automatic throttle a couple of days earlier in the maintenance log, but we don’t know what kind of problem. If we find the CVR (cockpit voice recorder) we will be able to listen to the discussion between the pilots, what they talked about and we will know what the problem is,” he told Utomo.
It is acceptable for a plane to fly with an automatic throttle system that does not work because pilots can control it manually instead, he added.
The plane’s flight data recorder (FDR) has been recovered and read by investigators, but the underwater search for the CVR unit at the crash site in the Java Sea continues.
Citing sources close to the investigation, the Wall Street Journal (WSJ) reported Thursday that FDR data showed that the automatic throttle system was not working properly on one of the plane’s engines as it climbed on takeoff from Jakarta.
Instead of shutting down the system, the FDR indicated that the pilots tried to run the stuck throttle. That could create significant power differences between the engines, making the plane more difficult to control, the WSJ added.
A preliminary report is expected to be issued within 30 days of the accident, in accordance with international standards.