Airliner May Have Stalled At 33,000 Feet
An MD-82 that crashed in Venezuela last August, killing 160, may have been behaving just the way Boeing had warned it might in a 2002 service bulletin. The bulletin warned that the autopilot might reduce engine power too much after a rapid climb, allowing airspeed to bleed off to the point of a stall. Pilots of the West Caribbean Airways flight, out of Panama for Martinique, may have been unaware, unnamed French investigators (Martinique is a French island) told the International Herald-Tribune. An interim report on the crash released by the Venezuelan government last November said the plane climbed from 31,000 feet to 33,000 feet and held the altitude for eight minutes before the autopilot turned itself off. The plane then descended for a minute before the stall horn sounded. It then fell to the ground at about 10,000 feet per minute, with the pilots pulling full back on the control yoke. The unnamed sources said the process would have happened gradually, with the autopilot trying to maintain altitude using pitch adjustments until shutting itself off just before the stall horn sounded. The pilots reported that both engines had flamed out but flight data recorder information indicated the engines were running normally when the descent began, although the right engine was cut back to idle shortly after. Data wasn't available for the left engine. Evidence from the wreckage shows both engines were turning at high speed at the point of impact. The recorder also shows that rather than push the nose over to recover from the stall, the pilots held the yoke to their chests all the way to the ground.