Accident Summary
On September 10, 2020, at 0915 eastern daylight time, an experimental amateur-built Vans RV6, registration N196DJ, sustained substantial damage during a forced landing near Melbourne, Florida. The pilot and passenger received minor injuries. The flight was conducted under Title 14 Code of Federal Regulations Part 91 as a personal flight.
Pre-Accident Maintenance
The pilot, who had recently purchased the airplane, reported that it had been in long-term storage for about 9 to 10 years without preservation. In the weeks preceding the accident, the pilot worked to return the airplane to an airworthy condition, addressing minor maintenance issues. This included partial removal of the No. 2 cylinder and a borescope inspection of the camshaft and other internal engine components, which revealed no corrosion. The cylinder was reassembled per manufacturer specifications. After 6 hours of flight without issues, an oil change was performed, and the suction screen was inspected, removing about 1/2 teaspoon of carbon deposits and sludge.
Engine Failure and Forced Landing
On the accident day, the pilot and a friend departed for local traffic pattern maneuvers. After completing pattern work, they flew to an offshore practice area. Suddenly, the engine began running "very rough." The pilot increased the mixture, but the engine shuddered and came to a "hard stop" with the propeller not windmilling. Attempting an engine restart, the pilot achieved about one full propeller rotation before the engine locked up. The pilot executed a forced landing on a beach, where the aircraft came to rest inverted, damaging the vertical stabilizer.
Post-Accident Examination
A visual inspection by a Federal Aviation Administration inspector found no external defects. One quart of residual oil was drained and checked for ferrous metal, with no anomalies detected in the oil, strainer, or filter. Spark plugs were removed, and a breaker bar was required to rotate the propeller. Valvetrain continuity was confirmed. Photographs showed oil streaked on the underside of the airplane, but the source of oil loss could not be determined during the examination.
Engine Disassembly
The pilot subsequently fully disassembled the experimental engine. Internal examination revealed that the oil pressure relief spring was corroded, pitted, and broken, and was loose within the housing. The crankshaft journals showed signs of overheating and scoring.
Maintenance Records Review
Aircraft maintenance logbooks indicated the engine was last overhauled in 1994, approximately 1,490 hours before the accident. Lycoming Service Instruction No. 1009BE recommends engine overhaul within 12 calendar years of first entry into service or last overhaul.