Report: Off-duty pilot saved doomed Lion Air plane on flight before fatal crash

The day before a Lion Air Boeing 737 MAX 8 aircraft plunged into the Java Sea, killing all 189 aboard, an off-duty pilot riding in the flight deck jumpseat of the same aircraft played a pivotal role in averting a similar crash, Bloomberg reports. On the flight that landed safely, the third pilot helped disable a malfunctioning flight-control system using an available checklist and saved the plane from crashing,

Details: The pilot disabled the plane's Maneuvering Characteristics Augmentation System (MCAS) from forcing the aircraft's nose down toward the ground, according to sources familiar who spoke with Bloomberg. The report adds that according to the Indonesia safety committee report, the plane had "multiple failures on previous flights and hadn't been properly repaired." One of the failures, it is widely thought, was a malfunctioning angle of attack sensor that was feeding erroneous information to the software system.