The menacing microburst: Wind shear, the single greatest cause of air crashes in the United States, may soon begin to yield to technological solutions

Off a runway at Stapleton Airport in Denver, Colo., one warm afternoon in late May 1984, 14 airplanes waited in line to take off. Near the end of the line were two United Airlines jets, Flights 663 and 161. The pilots of the two Boeing 727s scanned the sky above Runway 35 Left for signs of dangerous weather. The pilot of Flight 663 decided that ¿it looked like a typical Denver afternoon¿ and elected to take off. The pilot of Flight 161 said the sky looked ¿spooky¿ and decided to wait until conditions changed.