On May 12, 1995, a Cessna 170B (registration N4366B) was involved in an aviation accident near Chickaloon, AK. Investigators recorded the probable cause as: THE FRACTURE OF THE CRANKSHAFT RESULTING IN SEPARATION OF THE PROPELLER AND PROPELLER FLANGE IN-FLIGHT. A FACTOR ASSOCIATED WITH THE ACCIDENT WAS THE LACK OF SUITABLE TERRAIN FOR AN EMERGENCY LANDING. This summary draws on records from the U.S. National Transportation Safety Board (NTSB) historical archive.
During cruise at 6,500 feet MSL, the aircraft's propeller, propeller flange, and a portion of the crankshaft separated. The pilot executed a forced landing on a narrow road, landing uphill and downwind, resulting in a hard landing and the aircraft entering a ditch.
Incident Summary
While cruising at an altitude of 6,500 feet MSL, the pilot reported that the aircraft's propeller, propeller flange, and a portion of the crankshaft separated from the airplane. The pilot assessed the available landing options and determined that the only suitable site was a narrow road. Due to the surrounding terrain, the pilot was forced to land uphill and downwind.
Landing and Aftermath
The airplane touched down hard on the road. During the landing roll, the aircraft departed the road surface and entered a ditch. No further details regarding injuries or aircraft damage were provided in the source.
Missing Components
The separated propeller and associated components were not recovered after the incident.