In testing performed in a simulator, Boeing test pilots recreated the conditions aboard Lion Air Flight 610 when it went down in the Java Sea in October, killing 189 people. The tests showed that the crew of the 737 MAX 8 would have only had 40 seconds to respond to the Maneuvering Characteristics Augmentation System’s (MCAS’s) attempts to correct a stall that wasn’t happening before the aircraft went into an unrecoverable dive, according to a report The New York Times. by
While the test pilots were able to correct the issue with the flip of three switches, their training on the systems far exceeded that of the Lion Air crew—and that of the similarly doomed Ethiopian Airlines Flight 302, which crashed earlier this month. The Lion Air crew was heard on cockpit voice recorders checking flight manuals in an attempt to diagnose what was going on moments before they died.
One of the controls—the electric stabilizer trim thumbswitch on the pilot’s control yoke—could temporarily reset MCAS’s control over stabilizers. The Lion Air pilots hit this switch over 24 times, buying them some time—but MCAS’ stall prevention software kicked in afterwards each time because of faulty data coming from the aircraft’s primary angle of attack sensor.