It was just before sunset on September 8, 1994 as USAir flight 427 began it's approach into Pittsburgh. The flight had left Chicago earlier with Captain Peter Germano and First Officer Chuck Emmett at the controls. Along with three flight attendants, there were 127 passengers on board the 737. 427 was cleared to descend to 6,000ft to initiate it's approach to runway 28.

The aircraft continued to descend however, passing through 5,300ft. The aircraft then began to roll to the left out of control. It continue to roll over until it plunged into a wooded area outside the airport at nearly 300kts, killing all aboard.

......The crash of USAir 427 immediately raised red flags throughout the aviation world because of it's striking resemblance to the crash of United 585 three and a half years earlier.

It was clear at the time of the accident, though darkness was falling on Pittsburgh. There were no reports of any dangerous weather phenomena in the area of the airport. 427 had been following a 727 on the approach, trailing it by about four miles. Recovery of the FDR showed that 427 had encountered the wake turbulence of the trijet, but no abnormal forces were recorded. In an effort to confirm this, Boeing and USAir ran a study, flying a USAir 737 into the wake turbulence of another jet over 300 times. The USAir pilot reported that he never encountered any control upsets, but Boeing pilots reported that there could be sharp upsets of the aircraft in some encounters with wake turbulence.