Hemet - Hemet
Flight / Schedule
Hemet - Hemet
Aircraft
Lockheed C-130 HerculesRegistration
N135FF
MSN
3148
Year of Manufacture
1957
Operator
Hemet Valley Flying ServiceDate
August 13, 1994 at 01:31 PM
Type
CRASHFlight Type
Fire fighting
Flight Phase
Flight
Crash Site
Mountains
Crash Location
Pearblossom California
Region
North America • United States of America
Coordinates
34.5064°, -117.9098°
Crash Cause
Technical failure
Narrative Report
On August 13, 1994 at 01:31 PM, Hemet - Hemet experienced a crash involving Lockheed C-130 Hercules, operated by Hemet Valley Flying Service, with the event recorded near Pearblossom California.
The flight was categorized as fire fighting and the reported phase was flight at a mountains crash site.
3 people were known to be on board, 3 fatalities were recorded, 0 survivors were identified or estimated. This corresponds to an estimated fatality rate of 100.0%.
Crew on board: 3, crew fatalities: 3, passengers on board: 0, passenger fatalities: 0, other fatalities: 0.
The listed crash cause is technical failure. While in level flight, the airplane's right wing separated and, during the separation sequence, wing fuel ignited. Subsequent laboratory examination of right-side, center-wing fragments revealed two fatigue cracks that propagated to overstress fractures. One of the cracks was within the underside wing skin below a doubler, and the other was within the doubler itself. The total size and origin of the fatigue regions could not be determined due to damage to fracture surfaces and a lack of available material. The airplane was delivered new to the U.S. Air Force in December 1957 and was retired from military service in 1986. In May 1990, the FAA issued a restricted-category special airworthiness certificate authorizing the airplane to dispense aerial fire retardant. At the time of the accident, the airplane had a total of 20,289 flight hours, 19,547 of which were acquired during its military service. The inspection and maintenance programs used by the operator, which were based on military standards, included general visual inspections for cracks but did not include enhanced or focused inspections of highly stressed areas, such as the wing sections, where the fatigue cracks that led to those accidents were located. The operator did not possess the engineering expertise necessary to conduct studies and engineering analysis to define the stresses associated with the firefighting operating environment and to predict the effects of those stresses on the operational life of the airplanes.
Aircraft reference details include registration N135FF, MSN 3148, year of manufacture 1957.
Geospatial coordinates for this crash are approximately 34.5064°, -117.9098°.
Fatalities
Total
3
Crew
3
Passengers
0
Other
0
Crash Summary
While in level flight, the airplane's right wing separated and, during the separation sequence, wing fuel ignited. Subsequent laboratory examination of right-side, center-wing fragments revealed two fatigue cracks that propagated to overstress fractures. One of the cracks was within the underside wing skin below a doubler, and the other was within the doubler itself. The total size and origin of the fatigue regions could not be determined due to damage to fracture surfaces and a lack of available material. The airplane was delivered new to the U.S. Air Force in December 1957 and was retired from military service in 1986. In May 1990, the FAA issued a restricted-category special airworthiness certificate authorizing the airplane to dispense aerial fire retardant. At the time of the accident, the airplane had a total of 20,289 flight hours, 19,547 of which were acquired during its military service. The inspection and maintenance programs used by the operator, which were based on military standards, included general visual inspections for cracks but did not include enhanced or focused inspections of highly stressed areas, such as the wing sections, where the fatigue cracks that led to those accidents were located. The operator did not possess the engineering expertise necessary to conduct studies and engineering analysis to define the stresses associated with the firefighting operating environment and to predict the effects of those stresses on the operational life of the airplanes.
Cause: Technical failure
Occupants & Outcome
Crew On Board
3
Passengers On Board
0
Estimated Survivors
0
Fatality Rate
100.0%
Known people on board: 3
Operational Details
Schedule / Flight
Hemet - Hemet
Operator
Hemet Valley Flying ServiceFlight Type
Fire fighting
Flight Phase
Flight
Crash Site
Mountains
Region / Country
North America • United States of America
