Dirk Barreveld

Air Crash Investigations - Inadvertent in-Flight Slat Deployment - the Near Crash of China Eastern Airlines Flight 583 Dirk Barreveld

On April 6, 1993, a China Eastern Airlines McDonnell Douglas MD-11, flight 583, on its way from Beijing, China, to Los Angeles, California, had an inadvertent deployment of the leading edge wing slats while in cruise flight, not far from Shemya, Alaska. The autopilot disconnected, and the captain was manually controlling the airplane when it progressed through several violent pitch oscillations and lost 5,000 feet of altitude. Two passengers were fatally injured, and 149 passengers and 7 crewmembers received various injuries. The airplane did not receive external structural damage, but the passenger cabin was substantially damaged. The National Transportation Safety Board determined that the probable cause of this accident was the inadequate design of the flap/slat actuation handle by the Douglas Aircraft Company that allowed the handle to be easily and inadvertently dislodged from the UP/RET position, thereby causing extension of the leading edge slats during cruise flight.