Incident Details
According to the official investigation, the pilot was executing a near half-circle over the airport and entered a downwind leg for runway 14R. During the entry, he reduced power and noted two or three sputters from the engine. Just before turning to a base leg, he advanced the throttle for additional power, but there was no response from the engine.
Forced Landing and Impact
The pilot initiated a landing on a road, but a truck turned onto the roadway ahead. Subsequently, the aircraft touched down near the far edge of a small field, went through a fence, crossed a road, struck a road sign and a pole, and began burning. The aircraft was nearly consumed by fire.
Pre-Impact Observations
A helicopter pilot reported seeing black smoke or exhaust from the aircraft as it was circling to enter the traffic pattern. The pilot of the accident aircraft believed the engine had "loaded up" when he reduced power earlier in the pattern. Additionally, the pilot's son had flown the aircraft several hours and noted the engine ran smoother at high RPM.
Post-Accident Examination
Examination of the wreckage revealed evidence of an excessively rich fuel mixture just before the accident. Black sooty deposits were found in all cylinders and on the spark plugs and pistons. However, the aircraft and engine were too badly damaged to verify a specific reason for the rich mixture. No other preimpact problems were found.