Pilots of the Boeing 737 that crashed into the Java Sea in October fought relentlessly almost from the moment the plane took off to keep the plane from taking a nosedive, but apparently the automatic system was receiving incorrect sensor readings and as a result repeatedly forced the nose down, according to a preliminary report of the plane’s black box data recorder.
More than two dozen times during the 11-minute flight, pilots of the ill-fated Lion Air Flight 610 were able to force the nose of the plane back until they finally lost control, causing the plane to plummet into the Java Sea at 450 miles per hour, killing all 189 passengers on board.
Investigators had theorized the crash occurred due to a defect in the maneuvering characteristics augmentation system (MCAS), a computerized control system that Boeing had installed in its newer 737s. The system is designed to keep the plane’s nose from getting too high, which can cause a stall. In this case, the system’s sensors were relaying incorrect information, causing the plane to force the nose downward.
Following the crash, pilots raised red flags about Boeing not fully informing them of the new system. Boeing released a statement saying “the appropriate flight crew response to uncommanded trim, regardless of cause, is contained in existing procedures.” The crash is still under investigation.
In November, the family of an Indonesian doctor killed aboard Lion Air Flight 610 filed a lawsuit alleging that Boeing failed to warn pilots about the defect in the control system that can cause 737s to take unexpected nosedives.
New York Times