CHI95LA264

The pilot reported that shortly after takeoff, he leveled the airplane and adjusted the mixture control to the 'required lean mixture.' Suddenly the airplane started to lose altitude. Suspecting carburetor ice, he pulled the carburetor heat control on, but the engine RPM continued to drop and the engine then lost all power. The pilot attempted to make a forced landing on a road. At approximately 200 feet above the ground, the airplane stalled and impacted the ground. Postaccident examination revealed the numbers 3 and 4 spark plugs were sooty. The reported temperature was 91 degrees and the dew point was 71 degrees. This combination falls in the light icing category on the carburetor icing probability chart.

On August 8, 1995, at 1815 central daylight time, a Cessna 150L, N11346, operated by Airgo Incorporated of Centralia, Illinois, was substantially damaged following a loss of engine power and subsequent forced landing. The recently certificated private pilot reported the loss of engine power occurred shortly after taking off from Southern Illinois Airport, Murphysboro, Illinois. The pilot and one passenger were seriously injured. The 14 CFR Part 91 flight operated without a flight plan in visual meteorological conditions.

The pilot reported that he took off from runway 36R (5,801' x 100') and started to climb. He stated that at approximately 2,000 feet mean sea level, he leveled the airplane and adjusted the mixture control "with the required lean mixture." "Suddenly the [airplane] started losing height," the pilot stated. The pilot stated that the engine RPM began to drop. Suspecting carburetor ice, he pulled the carburetor heat ON, but the RPM continued to drop and the engine then lost all power. Not being able to return to the airport, the pilot decided to make a forced landing on a road. "I made an approach and was almost on my final but unfortunately, the [airplane] suddenly dropped from an altitude of approximately 200 feet and resulted in the accident," the pilot stated.

Cessna Aircraft Corporation and Teledyne Continental Motors were parties to the investigation. Postaccident examination revealed compression on all cylinders, the number 3 and 4 spark plugs were sooty, both magnetos sparked, and the carburetor was in good condition. No mechanical anomalies were found.

A surface weather observation was taken 20 minutes before the time of the accident. The reported temperature was 91 degrees and the dew point was 71 degrees. The attached Carburetor Icing Probability Chart places this temperature and dew point combination in the light icing category.