Amateur-built RV6 N196DJ accident near Melbourne, Florida

Probable cause

A total loss of engine power for reasons that could not be determined based on the available evidence.

NTSB analysis

The pilot/owner had recently purchased the experimental amateur-built airplane following a nearly decade long period of disuse. After spending several weeks inspecting the airplane and addressing minor maintenance issues, he flew the airplane for about 6 hours and noted no issues with the engine. Several days before the accident he changed the engine oil and removed about 1/2 teaspoon of carbon deposits and “sludge” from the oil screen. On the day of the accident, the pilot flew the airplane offshore and was performing maneuvers when the engine suddenly lost all power and the propeller stopped rotating. The pilot then performed a forced landing to a beach during which the and the airplane nosed over and came to rest inverted, resulting in substantial damage to the vertical stabilizer.

Postaccident examination of the airplane revealed that there was substantial oil streaking along the underside of the fuselage and that the propeller was not free to rotate without the application of additional leverage. Additionally, while the quantity of engine oil that remained was insufficient to sustain engine operation, the oil drained from the engine was absent of ferrous metal or other contaminates. Disassembly of the engine revealed that the oil pressure relief valve spring was corroded, pitted, and broken. Additionally, while internal engine components displayed signatures consistent with inadequate lubrication, no failures or damage that would have resulted in sudden engine stoppage were observed.

Text from the NTSB. Open the NTSB docket for ERA20LA316 for the full record.