NTSB Factual Report

On October 6, 2005, at 1710 central daylight time, an amateur built Kenny RV-4, N149KC, collided with the terrain during an off airport forced landing in Mitchell, South Dakota. The pilot was not injured. The airplane was substantially damaged. The 14 Code of Federal Regulation Part 91 personal flight was operating in visual meteorological conditions without a flight plan. The flight had originated from the Mitchell Municipal Airport (MHE) just prior to the accident.

The pilot reported he departed MHE and he was leveling off when the engine lost power. The pilot stated he switched fuel tanks, checked the magnetos and carburetor heat, and verified that the fuel pump was on, but he was not able to regain full power. The pilot reported that since he had "considerable altitude", he turned around to stay close to the airport. He stated he initially thought he would be able to make it back to the airport until the rate of descent increased and he determined he was not going to make it back to the airport. The pilot initially attempted to land on a highway, but becasue of traffic, he elected to land in a rough pasture.

Post accident inspection of the airplane revealed that bolts used to attach a air filter bracket to the carburetor had penetrated the carburetor bowl. When the filter bracket and bolts were removed, fuel, pieces of metal, and silicone came out of two of the four bolt holes.

The pilot had purchased the airplane on the day of the accident and was flying it from Lubbock, Texas, to his home airport when the accident occurred.

A review of the aircraft logbooks indicated an entry dated May 18, 1999, stated, "Replaced nose cowling and spinner to install Vans airfilter kit."

NTSB Probable Cause

The mechanic's improper installation of the air filter assembly which resulted in foreign debris inside the carburetor. A factor associated with the accident was the rough terrain on which the airplane was landed.