USAir Flight 427 crashed on Sept. 8, 1994, killing all 132 onboard. ... At the time, it was the longest investigation in the history of the National Transportation Safety Board.

It would take years for the National Transportation Safety Board (NTSB) ... An aerial view of the US Air Flight 427 crash site from 1,000 feet in the air on Sept. 13, 1994.

USAir Flight 427 crashed on Sept. 8, 1994, killing all 132 onboard. It is the deadliest in Pennsylvania’s history. The investigation took over four years.