Incident Overview
While transiting the Atlanta area, a commercial pilot reported a sudden loss of engine oil pressure and a subsequent severe vibration to Atlanta Approach Control. Approach Control vectored the flight toward Dekalb-Peachtree Airport for an emergency landing. Due to the loss of power, the pilot was unable to maintain altitude and was forced to land on a highway.
Emergency Landing and Collision
The pilot left the airplane in the cruise configuration and landed with the wheels and flaps retracted. Upon landing, the aircraft slid on the road, contacting a Jeep Cherokee, then impacting a Mazda 626. After the impact with the Mazda, the aircraft and the automobile caught fire, destroying both. The pilot sustained serious injuries, while the driver of the automobile was fatally injured.
Engine Examination
During a post-crash disassembly of the engine, the number five connecting rod was found fractured through the rod shoulder. A metallurgical examination revealed that the connecting rod had fatigue cracks originating at or near areas of galling. Connecting rods are routinely re-used following inspections for evidence of galling. The engine had operated to within about 60 hours of its recommended time between overhauls, with the broken rod installed.