Accident Boeing 747-121SF N771PA,
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Date:Thursday 27 December 1979
Type:Silhouette image of generic B741 model; specific model in this crash may look slightly different    
Boeing 747-121SF
Owner/operator:Pan American World Airways (Pan Am)
Registration: N771PA
MSN: 19661/70
Year of manufacture:1970
Total airframe hrs:34615 hours
Cycles:9505 flights
Engine model:Pratt & Whitney JT9D-7D
Fatalities:Fatalities: 0 / Occupants: 3
Aircraft damage: Substantial, repaired
Location:London-Heathrow Airport (LHR) -   United Kingdom
Phase: Landing
Departure airport:New York-John F. Kennedy International Airport, NY (JFK/KJFK)
Destination airport:London-Heathrow Airport (LHR/EGLL)
Investigating agency: AIB
Confidence Rating: Accident investigation report completed and information captured
The accident happened whilst the Boeing 747 cargo aircraft was being landed on runway 23 at London Heathrow Airport (LHR). At touchdown the number 4 pylon forward bulkhead, which supports the front of the engine, began to break free of the pylon because of weakening by fatigue and other pre-existing damage. The resulting downward movement of the engine during the landing roll ruptured the engine fuel feed pipe and several other connections with the engine including engine monitoring and fire warning circuitry. The high volume of fuel issuing from the ruptured fuel pipe caused a severe fire to develop under the number 4 pylon. The fire continued until the crew physically observed the fire as the aircraft was being turned off the runway at block 77(0), at which point the fire drill was carried out. This resulted in the closure of the fuel shut-off valve in the wing. The aircraft was brought to a halt and the airport fire service quickly brought the residual fire under control.

CAUSE: "The accident was caused by the failure of the forward bulkhead of the No 4 pylon when it was subjected to landing loads after it had been weakened by pre-existing fatigue. A major contributory factor was the absence of any routine check item which might otherwise have detected the onset of failure at an early stage."

Accident investigation:
Investigating agency: AIB
Report number: UNK80X0104
Status: Investigation completed
Duration: 1 year and 6 months
Download report: Final report



History of this aircraft

Other occurrences involving this aircraft
19 March 1992 N681UP United Parcel Service 0 Louisville, KY min


Revision history:


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