One of two sensors that measures the angle of attack is pictured at bottom on a Boeing 737 MAX 8 airplane outside the company’s factory on March 22, 2019 in Renton, Washington.
The release of the official report caps off weeks of leaks and speculation about the cause of the crash, much of it centering on the role of the MCAS anti-stall software.
Reports from the Wall Street Journal suggest that the MCAS automatically activated before the plane nose-dived into the ground.
In the Lion Air crash, the MCAS forced the plane’s nose down more than 24 times before it finally hit water, according to a preliminary investigation by Indonesia’s National Transportation Safety Committee, which found the system was responding to a faulty sensor.
The Wall Street Journal has also reported that pilots initially followed emergency procedures that were laid out by Boeing before the crash.
Questions have also been asked over whether pilots had sufficient training with the system.
Pilots transitioning to the Boeing 737 Max 8 aircraft from older 737 models were given a short, self-administered online course that made no mention of the MCAS system, pilots’ unions spokesmen for two American carriers told CNN.
Ethiopian Airlines CEO Tewolde GebreMariam has also said that the flight simulator that pilots trained on to learn how to fly the Boeing 737 Max 8 plane did not replicate the MCAS automated feature.