A new automated feature on the Boeing 737 MAX was among a series of factors that led to the crash of a Lion Air aircraft in Indonesia in Oct. 2018.
This is according to the final investigation report released on Friday.
The aircraft crashed into the Java Sea on Oct. 29, 2018, 13 minutes after taking off from Jakarta to Pangkalpinang on Bangka Belitung Islands province, killing all 189 people onboard.
Indonesia’s Transportation Safety Committee (KNKT) released on Friday its final investigation report on the accident.
The committee’s air crash investigator Nurcahyo Utomo said among the factors that caused the brand-new Boeing 737 MAX jet to crash were the design of cockpit software on the aircraft and no standards on how to solve the problem in one of the jet’s control systems.
Utomo said this in a news conference held at the committee’s office.
He said the plane’s Maneuvering Characteristics Augmentation System (MCAS) was approved based on incorrect assumptions.
The MCAS was a new automated feature introduced on the Boeing 737 MAX.
It automatically adjusts the aircraft by bringing its nose down when it detects that the aircraft is in imminent danger of entering an aerodynamic stall, based on data collected from the airspeed, altitude and angle of attack sensors.
“During the design and certification of the Boeing 737 MAX 8, assumptions were made about pilot response to malfunctions which, even though consistent with current industry guidelines, turned out to be incorrect,” Utomo said.
“The absence of guidance on the MCAS or more detailed use of trim in the flight manuals and in pilot training have made it more difficult for flight crews to properly respond to uncommanded MCAS,” he said.
The MCAS is suspected to have played a role in two deadly accidents involving Boeing 737 MAX 8 aircraft – the Lion Air Flight 610 and Ethiopian Airlines Flight 302.
Ethiopian Airlines Flight 302 crashed after taking off from Addis Ababa on its way to Nairobi in March this year, killing all 157 onboard.
Other factors contributing to the Lion Air plane crash were regulatory lapses and poor pilot training, said the committee.