NTSB Factual Report

On October 27, 2002, at 1300 central standard time, an amateur-built LaFerriere Vans RV-4 airplane, N994RV, owned and piloted by a private pilot, was substantially damaged during a forced landing following a loss engine power shortly after takeoff. The airplane had just departed runway 22 (2,300 feet x 40 feet, asphalt) at the Lake Geneva Aire Estates Airport (WI89), Lake Geneva, Wisconsin. Visual meteorological conditions prevailed at the time of the accident. The flight was being conducted under 14 CFR Part 91 and was not on a flight plan. The pilot and passenger reported no injuries. The intended destination was the Burlington Municipal Airport (BUU), Burlington, Wisconsin, approximately eight miles to the north.

In his written statement, the pilot reported: "After doing a run-up prior to my departure I applied full throttle and departed the runway. Moments later I noticed a loss of power and the engine quit running. Seeing that I had only about 125' to 150' of altitude I turned to the south to attempt a landing on the four lane highway. I pointed the nose of the aircraft downwards to prevent the aircraft from stalling and subsequently maybe spinning." The aircraft landed on the shoulder of the southbound traffic lane and "proceeded into the ditch, paralleling the highway. The aircraft came to an abrupt stop after doing a ground loop."

A post-accident examination was conducted. Fuel was present in the fuel tanks, with no evidence of contamination present. Engine continuity was confirmed through crankshaft rotation. All cylinders exhibited compression. The engine driven and electric fuel pumps were tested and appeared to operate normally. The left magneto provided spark across all leads. The right ignition system was electronic and was not tested.

The lower portion of the carburetor was sheared from the engine. The upper portion remained intact. The venturi appeared undamaged and the throttle valve appeared to operate normally. The lower cowling was detached from the airframe.

Weather conditions reported by the Burlington Municipal Airport (BUU) Automated Weather Observing System (AWOS), located 8 miles north-northwest of WI89, at 1258 cst, included an air temperature of 7 degrees Celsius and a dew point of -2 degrees Celsuis.

According to data provided by Transport Canada, a possibility of serious carburetor icing at descent power existed at the time of the accident.

NTSB Probable Cause

The loss of engine power due to carburetor ice. A contributing factor was the ditch adjacent to the roadway.