Investigators in the deadly crash of an Ethiopian Airlines flight have reached a preliminary conclusion that the Boeing 737 MAX 8’s automated anti-stall system was activated before the jet plunged to the ground, according to a report.
The finding — based on information from the doomed jet’s black boxes — shows that the malfunctioning Maneuvering Characteristics Augmentation System, or MCAS, may have caused the March 10 crash, which killed 157 people, The Wall Street Journal reported.
It also is a strong link to the Indonesian Lion Air MAX 8 that experienced similar problems when it crashed Oct. 29, killing all 186 people aboard.
Citing people with knowledge about the probe, the Journal said the consensus among investigators was revealed during a high-level briefing at the Federal Aviation Administration on Thursday.
An Ethiopian Ministry of Transport spokesman said he knew nothing about the report. Ethiopian officials were expected to release their preliminary findings shortly.
Ethiopian Transport Minister Dagmawit Moges previously said that data from the black boxes showed “clear similarities were noted” between both fatal flights.
Boeing, which this week unveiled a fix to the much-maligned system, and the FAA have not commented about the preliminary finding, which people briefed on the matter told the Journal is subject to revisions.
Officials have said the both planes followed similar erratic flight paths — climbing and descending before crashing a few minutes after takeoff.
The MCAS is designed to automatically point the nose of the plane down if it senses potential for a loss of lift, or aerodynamic stall.
The system’s software takes readings from two so-called angle-of-attack sensors, which determine how much of the nose is pointing up or down relative to the flow of air.
In another development, Reuters reported Friday that US and European regulators knew at least two years before the Indonesian disaster that the usual method for controlling the MAX’s nose angle might not work in conditions similar to those in the two recent crashes.
The European Aviation and Space Agency certified the plane as safe partly because it said additional training would “clearly explain” to pilots the “unusual” situations in which they would need to manipulate a rarely used manual wheel to control, or “trim,” the plane’s angle.
But those scenarios were not listed in the flight manual, according to a copy from American Airlines seen by Reuters.
EASA and the FAA ultimately determined that set-up was safe enough for the plane to be certified.
Meanwhile, the family of Rwandan citizen Jackson Musoni, a UN worker who was killed in the Ethiopian crash, has filed a lawsuit against Boeing in Chicago federal court, alleging that the plane maker had defectively designed the anti-stall system.
“Boeing, having knowledge of all the reports of dangerous conditions and the previous accident that killed over 150 people, should have taken steps to protect the flying public,” said attorney Steve Marks, who is representing Musoni’s relatives, the Washington Post reported.
“This accident happened when it should have never happened,” he said.
Boeing said it could not comment on the lawsuit.
“Boeing … is working with the authorities to evaluate new information as it becomes available,” it said, adding all inquiries about the investigation must be directed to the investigating authorities.
Boeing’s 737 MAX planes will remain grounded around the world until the FAA and other agencies certify the software fix and crews are trained on the revised system.