On May 14, 2005, a Republic RC-3 (registration N6292K) was involved in an aviation accident near Geyserville, CA. Investigators recorded the probable cause as: A loss of engine power due to failure of the number 1 connecting rod bearing due to a probable oil starvation. This summary draws on records from the U.S. National Transportation Safety Board (NTSB) historical archive.
During a flight, an engine lost power after oil temperature and pressure anomalies. A connecting rod failure caused a hole in the engine case. The pilot performed a gear-up landing in a vineyard, nosing over.
Event
Shortly after takeoff, the engine lost power. The pilot and a pilot/mechanic passenger noted a rise in oil temperature and a corresponding drop in oil pressure approximately 7 miles into the flight. A rear seat passenger heard banging and clattering from the engine. The pilot attempted to reach an alternate airport, but after a loud bang, the engine lost power, and the pilot performed an emergency landing in a vineyard with the landing gear retracted, causing the airplane to nose over.
Engine Examination
Examination of the engine revealed that the number 1 connecting rod had separated and knocked a hole in the engine case. The connecting rod end cap exhibited deformation and bluing. The associated rod journal displayed bearing transfer, characterized by a bronze/orange discoloration. Oil was present both inside the engine case and on the outside of the engine cowling. Oil drained from the oil sump contained metal debris. The spark plugs for the number 1 and number 3 cylinders were oil sooted and had foreign debris around the electrodes.