Mechanical and design defects in the flight control system are key to the crash of a Lion Air Boeing 737 Max aircraft off Indonesia last year, Indonesian investigators said on Wednesday. families of the victims.
"During the design and certification of the (737 MAX), assumptions were made regarding the pilot's response to failures which, while in compliance with the applicable directives, did not produce the expected effect", according to the final report of the Indonesian National Committee for Transport Safety, presented behind closed doors to families at a closed meeting in Jakarta.
The final report on this accident on October 29, 2018 is due to be released this week, according to media reports. In particular, the Committee referred to the "contributory factor" of the malfunctions of the MCAS, an automatic system that was supposed to prevent the aircraft from going into a dive.
The report states that the system was vulnerable because it was based on only one sensor and that it, replaced on the aircraft of Lion Air crashed, was "poorly calibrated" during a repair.
According to the Indonesian authorities' findings, the fact that the 737 MAX pilots did not receive instructions to deal with this type of malfunction has made matters worse.
"As the report was not officially released by the investigating authorities, it is premature for us to comment on its contents," a spokesman for Boeing told AFP.
The 189 passengers and crew of the Boeing 737 MAX were killed in October 2018 when the aircraft crashed in the Java Sea shortly after taking off from Jakarta.
In March, a single plane belonging to the Ethiopian company, which ran from Addis Ababa to Nairobi, crashed, killing 157 people.
In both cases, the MCAS automatic system was questioned.
The entire world fleet of the 737 MAX has since been grounded.
A committee of the World Civil Aviation Authorities (JATR) recently found that the US Federal Aviation Agency (FAA) failed to properly assess the MCAS because it lacked engineers and expertise .
The meeting with the victims' families was held in the wake of the dismissal of Kevin McAllister, the head of his commercial aviation division (BCA), the first departure of a senior executive since the start of the 737 MAX crisis.
© 2019 AFP