... In a vacuum of evidence about what went wrong aboard the flight, speculation turned to the possibility of pilot suicide, an extraordinarily rare occurrence.
“You have to ask the question,” said a U.S. aviation official who was not authorized to discuss the matter publicly.
The Malaysia Airlines flight reportedly was being tracked by radar when its transponder went dark. There were no radio transmissions to indicate that anything was amiss aboard the plane. The transponder signals and radio communication are controlled by the pilot.
There have been two cases in recent years in which a pilot or crew member is believed to have intentionally caused a plane to crash: the disaster involving SilkAir Flight 185, which spiraled into the ground in Indonesia in 1997, killing 97 passengers and seven crew members; and the crash of EgyptAir Flight 990, which plunged into the Atlantic south of Nantucket in 1999, killing 217 people.