CHI08LA134

The pilot reported that during flight, at about 2,000 feet mean se level (msl), he was unable to maintain altitude and decided to divert to his home airport. He said that he made a gradual left turn and had descended to 1,000 feet msl when the stall warning horn activated. He stated that he applied full power, but the airplane continued to stall and he attempted to land in a clearing on the other side of a stand of trees. The airplane subsequently hit the trees and the ground during the forced landing. Global positioning system data retrieved from a unit on board the airplane indicated that the airplane began a left-hand spiraling descent about 5 minutes prior to impact. The spiraling descent began at about 1,600 feet msl and consisted of 6 complete left-hand turns that ended at a recorded altitude of about 650 feet msl. The average speed during the descent was about 60 knots and the average descent rate was about 250 feet per minute, indicating a reduced power descent. Further evidence indicated that the nearest residence to the accident site was the home of a relative of the pilot. Analysis of the weather conditions indicated that they were favorable for moderate icing at cruise power settings or serious icing during descent power settings.

On May 12, 2008, about 1835 central daylight time (all times central standard time), a Cessna 150M, N66381, piloted by a private pilot, sustained substantial damage when it struck trees and terrain near Palestine, Illinois. The 14 Code of Federal Regulations Part 91 personal flight was operating in visual meteorological conditions without a flight plan. The pilot received serious injuries. The flight originated from the Daviess County Airport (DCY), Washington, Indiana, at 1758.

In a written report, the pilot stated that he performed a preflight examination of the airplane prior to his departure from the O'Neal Airport (OEA), Vincennes, Indiana. He stated that during the takeoff from OEA, the airspeed indicator read zero. The pilot stated that he continued the flight and climbed to 2,200 feet msl and headed toward DCY. He stated that he landed at DCY and taxied the airplane to a hangarand cleaned the airplane and checked all devices to see if there were any obstructions. The pilot made the decision to takeoff and fly the airplane toward the Robinson Municipal Airport (RSV), Robinson, Illinois, and then back to OEA. He stated that during the takeoff and climb, the airspeed indicator seemed to be working but the airplane "wanted to stal" l at 60 knots indicated airspeed. The pilot stated that he lowered the pitch attitude and climbed to 2,200 feet. He reduced the engine power setting to 1,800 rpm. He stated that a short time later, he was at 2,000 feet and then later at 1,600 feet. The pilot stated that at this time he decided not to continue to RSV, and to turn back to OEA. He made a gradual left turn and had descended to 1,000 feet when the stall warning horn came on. He stated that he applied full power but the airplane continued to stall. He said that he knew of a clearing on the other side of the woods and attempted to make the clearing. The airplane subsequently struck trees and the ground.

On board the airplane at the time of the accident was a Garmin GPSMap 396 global positioning system (GPS) receiver. The GPS was retained and the track data downloaded from the unit. The ground track showed that the airplane departed OEA and proceeded to DCY. During this portion of the flight, the airplane made several course changes and 360 degree turns with altitude variations between 2,300 feet and 600 feet msl prior to landing at DCY. The data showed that the airplane remained at DCY for about 17 minutes prior to departing DCY at 1758. After departing DCY, the data showed that the airplane remained in the airport traffic pattern and one landing was executed. The airplane then climbed to about 2,130 feet msl, its speed stabilized at about 85 knots, and the ground track proceeded northwest toward RSV. About 5 minutes prior impact the airplane began a left hand spiraling descent. The spiraling descent began at about 1,600 feet msl and consisted of 6 complete 360 degree left hand turns that ended at a recorded altitude of about 650 feet. The average speed during the descent was about 60 knots and the average descent rate was about 250 feet per minute. The last recorded position coincided with the reported accident location and the recorded altitude was 633 feet msl.

According to a Sherriff's report, the person who lived in the residence nearest the accident site was a relative of the pilot.

According to maintenance records, the most recent annual inspection was performed on March 27, 2007.

Examination of the airplane subsequent to the accident revealed no pre-impact anomalies with regard to the airframe or control system components. The induction air filter had paint overspray on the filter element. About 4 gallons of fuel was found in the left fuel tank. The right fuel tank contained about 5 gallons of fuel. Examination of the engine was conducted. The crankshaft was free to rotate and valve system continuity was established. All cylinders exhibited valve movement and produced compression during engine rotation. Both magnetos produced spark from all leads during engine rotation. The carburetor was broken loose from the induction system but no anomalies were detected. Fuel was found in the carburetor float bowl and in the fuel lines leading to the carburetor. No anomalies that would have prevented engine operation were detected.

The recorded weather conditions at RSV at 1825 were: calm winds; 10 miles visibility; clear skies; temperature 19 degrees Celsius; dew point 4 degrees Celsius; altimeter setting 29.96 inches of Mercury.

According to a carburetor icing probability chart, the temperature and dew point readings were favorable for moderate icing at cruise power settings or serious icing during descent power settings.