What happened
Prior to departure, the Cessna (type not specified in source) had been refueel with 37.5 gallons of 100 low lead fuel. Shortly after takeoff from runway 23, the pilot reported hearing a pop or bang from the engine, followed by an apparent loss of power and severe vibration. In an attempt to return to the airport, the pilot executed a 180-degree left turn. The aircraft subsequently landed in a grass field, where it impacted a dirt embankment and a fence before coming to rest upright in a ditch. There were no injuries reported.
The investigation
An examination of the aircraft revealed that the throttle cable was routed above the rear-mounted alternator belt, causing the cable to rest on the belt. This contact had worn through the throttle cable shielding, leaving the braided cable exposed, although no damage was found on the braided portion itself. Additionally, one tube of the engine mounting frame was found to have a fracture consistent with an overload failure.
Mechanical continuity throughout the engine was confirmed by rotating the propeller by hand and performing a one-minute ground test run at 1,300 RPM. No anomalies were observed during this test run. A review of the aircraft logbooks indicated that annual and 100-hour inspections had been completed between the installation of the overhauled engine and the accident.