USAir Flight 427
From Wikipedia, the free encyclopedia
| Summary | |
|---|---|
| Date | September 8, 1994 |
| Type | Loss of control |
| Site | Aliquippa, Pennsylvania |
| Fatalities | 132 |
| Injuries | 0 |
| Aircraft | |
| Aircraft type | Boeing 737-300 |
| Operator | USAir |
| Tail number | N513AU |
| Passengers | 127 |
| Crew | 5 |
| Survivors | 0 |
US Airways Flight 427 was a scheduled flight from Chicago's O'Hare International Airport to Pittsburgh, Pennsylvania, with a final destination of West Palm Beach, Florida. The flight crashed on September 8, 1994, killing everyone on board.
The Boeing 737-3B7 flying the route, registered N513AU, was approaching runway 28R of Pittsburgh International Airport, located in Findlay Township, Pennsylvania. At about 6,000 feet (1,830 meters) and 6 miles (10 km) from the runway, the aircraft experienced a sudden loss of control and slammed into the ground in a nearly vertical nose down position in Hopewell Township near Aliquippa, Pennsylvania, killing all 127 passengers (including a 2.5 year old baby named Narod Ardhaldjian who was sitting on her mother's lap and was initially not counted) and 5 crew members.
After the longest investigation in aviation history—more than four and a half years—the concluding statement said:
- The National Transportation Safety Board determines that the probable cause of the USAir flight 427 accident was a loss of control of the airplane resulting from the movement of the rudder surface to its blowdown limit. The rudder surface most likely deflected in a direction opposite to that commanded by the pilots as a result of a jam of the main rudder power control unit servo valve secondary slide to the servo valve housing offset from its neutral position and overtravel of the primary slide. [1]
The NTSB concluded that similar rudder problems caused the previously mysterious March 3, 1991 crash of United Flight 585, and the June 9, 1996 incident involving Eastwind Airlines flight 517, both of which were Boeing 737s.
As a result of the investigation, pilots were warned of and trained how to deal with insufficient aileron authority at an airspeed at or less than 190 knots (218 mph, 354 km/h), formerly the usual approach speed for a B737. Four additional channels of information—pilot rudder pedal commands—were incorporated into flight data recorders, while Boeing redesigned the rudder system on 737s and retrofitted existing craft until the affected systems could be replaced. Congress also required airlines to deal more sensitively with the families of crash victims.
427 is no longer a valid flight number on US Airways.
[edit] External links
- NTSB Accident Investigation Docket
- AVweb article
- AVweb supplement
- Accident description on the Aviation Safety Network
- 28 Seconds Four-part article from the Saint Petersburg Times
[edit] Books
- Bill Adair, The Mystery of Flight 427: Inside a Crash Investigation, ISBN 1-58834-005-8
- Gerry Byrne, Flight 427: Anatomy of an Air Disaster, ISBN 0-387-95256-X
