Lion Air plane not airworthy before fatal crash, investigators say
The plane, which crashed into the sea off Indonesia in October, experienced technical difficulties on a previous flight.
Wednesday 28 November 2018 11:03, UK
The Lion Air plane that crashed into the sea last month - killing all 189 on board - was not airworthy on its previous flight, investigators have found.
Pilots of the Boeing 737 struggled to control the aircraft after takeoff, according to a report from Indonesia's national transport safety committee.
On 28 October, the day before the fatal crash, the same plane experienced technical difficulties as it flew from Bali to Jakarta.
The pilot should have discontinued the flight, the National Transport Safety Committee found. Instead he carried on to Jakarta.
The findings come from a preliminary report into the crash by Indonesian authorities. The report details the initial investigation but does not include analysis or a conclusion.
Authorities have recovered the flight data recorder but are still looking for the other black box - the cockpit voice recorder, which should shed more light on the cause of the accident.
The report describes the difficulties encountered by the pilots of Lion Air Flight 610 shortly after takeoff.
They repeatedly told air traffic control they had a flight control problem. They also advised that they could not determine their altitude because all their instruments were giving different readings.
The flight data recorder stopped recording 31 seconds after the pilots' last communication with control.
Based on the wreckage recovered from the crash site "the damage to the aircraft suggested a high energy impact", according to the report.
The black box data indicates irregularities in altitudes, with the aircraft rising and sinking throughout the flight.
The data also shows that the aircraft automatically tried to push the plane of the nose down, then the flight crew tried to push the nose back up. This continued during the whole the flight.
Boeing 737-MAXs contain automated systems to prevent an aircraft stalling if its nose is too high.
Investigators are exploring whether faulty sensor data might have caused the automatic system to kick in and force the plane's nose down.
The pilot of the same Boeing 737 reported similar issues the day before the Lion Air crash.
However, after three attempts by the aircraft to automatically put its nose down, he discontinued the system and took manual control, landing the plane safely in Jakarta.
The issue was reported, addressed and deemed solved after testing.