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The craft was ripped apart on impact, its pieces strewn over five acres. Its largest sections, including about 45 ft. of the rear fuselage, spun into a swampy field, caromed across Rockaway Boulevard, which would have been jammed with home-bound traffic an hour later, and ripped through a wire fence. The rear section came to rest upside down and afire.
Amazingly, two flight attendants, Mary Mooney, 28, of Tulsa, Okla., and Robert Hoefler, 29, of New York, managed to stumble out of the wreckage in a daze. They had been in the last row of seats. Twelve other passengers were found alive by rescue workers.
Mostly, the rescuers found only broken bodies. By week's end 111 persons had died, predominantly because of impact injuries rather than fire. Another ten were in critical condition. The death toll equalled the 111 deaths recorded in the crash of an Alaska Airlines 727 into a mountain near Juneau in 1971, until now the worst single-plane accident in U.S. aviation.
Lethal Force. What had gone wrong? With their usual dispatch and customary caution about premature conclusions, investigators from the National Transportation Safety Board launched an inquiry that will take months to complete. But their guarded comments indicated great skepticism that lightning had knocked the plane out of the sky, as was suggested by no fewer than 27 witnesses. Instead, the experts hinted that "wind shear" will almost certainly be cited as a major, if not the primary probable cause of the crash.
If so, another hazard to air travel will gain new prominence in the minds of millions of already nervous passengers. Wind shear carries a frightening connotation of lethal slicing forces, and with good reason. It is a highly unpredictable and violent weather phenomenon that results when opposing squall lines of high-velocity winds cross or collide. The result is a whirlwind, minitornado effect in which wildly thrashing air currents can throw even huge aircraft out of control when they are flying at relatively low landing speeds, generally around 180 knots. During the critical moments of landing, there is little time for a pilot to recover from such unexpected buffeting, and ground obstacles are often perilously close.
"We began denning wind shear and identifying it as hazardous only in the past decade," explains Charles Miller, director of safety seminars for the Flight Safety Foundation. "It is treacherous. An aircraft may be stabilized flawlessly on an instrument approach, with thrust setting, airspeed, flaps and rate of descent all coordinated. Then comes a vertical gust. Or a gust from the rear. A head wind suddenly becomes a tail wind, and the aircraft's rate of sink suddenly accelerates. Only recently have we begun to appreciate the variations and magnitude of wind shear."