Faulty information from a single external sensor forced down the nose of Lion Air Flight 610. So conclude Indonesian investigators a year on from the crash that killed 189 people and raised safety concerns about the Boeing 737 Max. The jet's new flight-control system was vulnerable to errors—that external sensor hadn't been properly tested—yet Boeing assumed pilots would know how to respond if the plane nose dipped uncommanded, Indonesia's National Transportation Safety Committee writes in the final crash report. That's despite the fact that the anti-stall Maneuvering Characteristics Augmentation System wasn't mentioned in the flight manual or in flight crew training, per the Guardian. The report also mentions a lack of documentation about earlier issues with the same jet, which should've been grounded.
The crash might still have been avoided had the captain not handed the controls to his first officer, who "struggled to run through a list of procedures that he should have had memorized," per the BBC. The report adds 31 pages were missing from the plane maintenance log. Boeing—whose profits were down 51% in the third quarter—said Friday that "software changes will prevent the flight control conditions that occurred in this accident from ever happening again." The FAA is reviewing the changes—to how sensors feed information to the cockpit as well as updated manuals and training—to determine if the 737 Max can safely take to the air. (It was grounded after the MCAS malfunctioned in the Ethiopian Airlines crash that killed 159 people in March, reports the Washington Post, though Boeing expects approval before the end of the year.)