British and American investigators are still piecing together flight data to determine why a Boeing 777's engines suddenly refused to increase power just short of landing, causing the plane to crash-land at London's Heathrow airport on Thursday. The unexplained crash has drawn worldwide puzzlement, as the popular passenger plane previously enjoyed an exemplary, accident-free safety record, USA Today reports.
"It's a mystery from what I see so far," one academic said. Complex computers aboard the aircraft might have malfunctioned, sending the wrong message to engines; the jet's fuel supply could also be to blame. Investigators have not yet ruled out any potential cause of the crash—including human error, despite the much-publicized heroism of pilots in landing it safely.