JAKARTA (Reuters) – A pilot of a doomed Lion Air jet told air traffic control that the plane was experiencing a “flight control problem” shortly before it crashed into the Java Sea last month, Indonesian investigators said on Wednesday.
Ahead of the release of its first report, transport safety committee KNKT gave more details on the problems the pilots faced in controlling the Boeing Co 737 MAX flight before it crashed on Oct. 29, killing all 189 people on board.
During the early morning flight, one of the pilots asked flight controllers to confirm the altitude and speed of the aircraft.
The pilot then reported that they were experiencing a “flight control problem,” the statement said.
Last week, KNKT investigator Nurcahyo Utomo told parliament that the jet’s Maneuvering Characteristics Augmentation System (MCAS) – an automated modification new to the model that crashed – activated and directed the jet’s nose down to prevent a stall.
The jet’s systems had detected it was in a stall due to a faulty indicator and gave the captain a warning through a “stick shaker” that vibrated the controls, he said.
Pilots flying the same plane a day earlier had experienced a similar problem until they used switches to shut off the system, KNKT said in its statement on Wednesday.
The agency recommended that Lion Air improve its safety culture to ensure that a pilot can make proper decisions to continue a flight.
The investigation into the crash is in its early stages and is hampered by the lack of evidence from the cockpit voice recorder, which remains lost on the seabed.
KNKT has not yet said what caused the crash and the recommendations are an indication of areas of focus, but not necessarily the ultimate cause.
On Wednesday, KNKT acknowledged actions to improve safety had been taken by Boeing, Lion Air, the U.S. Federal Aviation Administration (FAA) and Indonesia’s Directorate General of Civil Aviation.
At Indonesia’s request, Boeing issued an advisory about MCAS to airlines earlier this month. That was quickly followed by a U.S. Federal Aviation Administration directive making that mandatory.