Amateur-built KITFOX 4 N69377 accident near Flintstone, Maryland

Probable cause

A total loss of engine power due to the lack of sufficient lubrication and the pilot/owner’s failure to adequately service the airplane’s engine.

NTSB analysis

The pilot was flying at an altitude of 2,800 feet mean sea level when the engine of his homebuilt airplane abruptly lost power. After many failed attempts to restart the engine, the pilot landed in a wooded area. The airplane came to rest in a nose-low attitude suspended off the ground between two trees. The pilot sustained minor injuries and the airplane incurred substantial damage. An examination of the engine found evidence of inadequate lubrication to the engine’s rotary valve and foreign material and debris in both carburetors. During the examination, the rotary valve was only able to produce a few turns of the propeller before it stuck in a position that cut off the fuel/oil mixture’s flow to the cylinder. The rotary valve’s oil tank was empty and the pilot stated that he had never added any oil to it in the 49 hours the airplane was operated. Review of the engine’s operators and maintenance manuals revealed that the engine had been improperly stored for 18 years.

Text from the NTSB. Open the NTSB docket for ERA09LA491 for the full record.