The pilots of Lion Air's Boeing 737 Max 8 that crashed last year reportedly hit an rebalancing switch repeatedly in an effort to save the plane, unaware that they needed to take three further steps.
Sources investigating the crash told The New York Times that the pilots flying the Boeing plane pressed a switch meant to rebalance a destabilization caused by a piece of software called the Maneuvering Characteristics Augmentation System, which investigators believe was forcing the plane into a dive.
The plane crashed less than 15 minutes after it took off from the Indonesian capital of Jakarta's Soekarno-Hatta International Airport, killing all 189 people on board.
The sources told The Times that while triggering the switch was the right first move, three more steps would have been needed to be taken to save the plane.
According to the investigators, the full process ought to have been:
- Attempt to delay the MCAS error.
- Press a switch to turn off a motor controlling the angle of the nose.
- Press a second switch to confirm the motor shutdown.
- Turn a wheel to re-angle the plane's nose and stop the dive.
The plane pushed its nose down for nine minutes before it hit the sea, according to a report from Reuters that cited investigative sources.
The report said audio from a cockpit recorder showed the pilots seeking a solution in the plane's technical manual but ultimately running out of time.
The investigation into the crash is still underway and is not due to be complete until August. Investigators are widely believed to be focusing on MCAS in determining the cause of the crash.
It has taken on new urgency since a different 737 Max 8, operated by Ethiopian Airlines, crashed in circumstances officials say are similar to those of the Lion Air crash.
Boeing is expected to roll out a software update meant to give pilots more control over MCAS and make it less likely to malfunction.
After the Ethiopian Airlines crash, however, many countries grounded the 737 Max, including China, the US, and the European Union.
