Pilots Battle Computer For Control Of 777
Stanley Kubrick couldn't have scripted anything more eerie than the real-life odyssey of a Malaysian Airlines Boeing 777 that seemed hell-bent on crashing itself on a trip from Perth to Kuala Lumpur last Aug. 1. According to The Australian newspaper, the Malaysian flight crew had to literally battle for control of the aircraft after something went wonky with the computerized controls. The plane was about an hour into the flight when it suddenly climbed 3,000 feet and almost stalled. The Australian Transport Safety Bureau report said the pilot was able to disconnect the autopilot and lower the nose to prevent the stall but the autothrottles refused to disengage and when the nose pitched down they increased power. Even pushing the throttles to idle didn't deter the silicon brains and the plane pitched up again and climbed 2,000 feet the second time. The pilot was able to fly manually back to Perth but the autothrottles wouldn't turn off. As he was landing, the primary flight display gave a false low airspeed warning and the throttles firewalled again. The display also warned of a non-existent wind shear. Boeing spokesman Ken Morton said it was the only such problem ever experienced on the 777 but airlines have been told via an emergency AD to load an earlier software version just in case. The investigation is focusing on the air data inertial data reference unit (HAL for short?), which apparently supplied false acceleration figures to the primary flight computer.