On February 20, 1972, a Beechcraft 80 Queen Air (registration N1027C) operated by Sun Valley Key Airlines was involved in an aviation accident near Fairfield-Camas County, United States of America in flight. 5 people were killed. Investigators recorded the probable cause as: Engine failure in normal cruise followed by an airframe failure. Contributing factors: improper maintenance by maintenance personnel, powerplant failure due to improperly installed cylinder assembly, engine fire, fire in brakes/wheel assembly/wheel well,… This summary draws on records from the Bureau of Aircraft Accidents Archives (B3A).
While at cruising altitude, the left engine of an aircraft caught fire and exploded, leading to left wing separation and an uncontrolled descent. The aircraft crashed near Fairfield, killing all five occupants.
Accident Sequence
While the aircraft was at cruising altitude, the left engine caught fire and subsequently exploded. Shortly after the explosion, the left wing separated from the aircraft. The aircraft, now out of control, dove into the ground and crashed near Fairfield. All five occupants were killed.
Probable Cause and Contributing Factors
The official investigation determined the probable cause to be an engine failure during normal cruise followed by an airframe failure. The following factors were reported as contributing to the accident:
Improper maintenance by maintenance personnel
Powerplant failure due to an improperly installed cylinder assembly
Engine fire
Fire in brakes, wheel assembly, and wheel well
Separation in flight
Cylinder separation
Excessive working hours (noted as possibly contributing)
The investigation did not specify the aircraft type, registration, operator, or other identifying details.