On December 6, 1997, at 1409 eastern standard time, a Cessna 172B, N172MT, collided with a tree, and the ground, while maneuvering for an emergency landing one mile north Henderson, North Carolina. The personal cross country flight operated under the provisions of Title 14 CFR Part 91 with a flight plan filed. According to weather data recovered from the nearest reporting facility, visual weather conditions prevailed at the time of the accident. The airplane sustained substantial damage. The airline transport pilot, and his passenger were not injured. The pilot stated that the cross country flight departed Hazleton, Pennsylvania, at 1037. The pilot reported that the ultimate destination for the flight was Peoria, Arizona The pilot reported that the destination airport and planned refueling stop was the Oxford-Henderson Airport. He had flight planned three hours and twenty-two minutes of flight time for this leg of the flight; the airplane had a fuel endurance of five hours. While cruising at 2500 feet, approximately three hours and twenty minutes into the flight, and two miles north of Oxford Henderson Airport, the pilot noticed that the engine rpm had dropped, followed by a total loss of engine power. Attempts, by the pilot, to restore full power, failed. The pilot stated that he completed the following engine restart procedures: the mixture lever was set to the full rich, the carburetor heat lever was in the on position and the fuel selector was moved from the both position to the right then back to the both position. The pilot selected a forced landing area, and established an approach. While maneuvering for the emergency landing, the right wing struck a tree, and the airplane came to rest in a freshly plowed field. During the on site phase of the wreckage examination, a substantial amount of fuel was discovered in the fuel tanks. No obvious aircraft system malfunctions or component failures were noted during the on site examination. The aircraft wreckage was not immediately recovered from the accident site due to wet weather conditions. After several months, the wet field was dry enough for the aircraft recovery operation. An examination of the engine assembly was completed. During the engine examination it was noted that the spark plugs showed normal wear. The engine was also rotated through using the propeller shaft. It was noted that all internal engine components rotated normally. Since the spark plugs had been removed, a thumb compression check was also completed; all cylinders produced what appeared to have been normal compression. Both magnetos produced ignition sparks to all spark plugs. The gascolator assembly was also examined, and he noted that a small quantity of what he described as automotive fuel was in the fuel system. The examination of the engine assembly failed to disclose a mechanical problem or a component failure. The pilot did not report experiencing an airplane problem prior to the total loss of engine power. The pilot recalled that the outside air temperature, at 2500 feet, was 25 degrees Fahrenheit when the engine lost power. A review of weather data from the nearest reporting facility, 30 miles south of the accident site, reported a temperature of 40 degrees Fahrenheit at the approximate time of the accident (see attached icing probability curves). According to the pilot, carburetor heat was last used about 45 minutes before the loss of engine power; carburetor heat was applied and returned to the cold position following a change of altitude maneuver. The carburetor heat lever was in the cold position when the engine lost power. The pilot reported that the airplane had been refueled with 100 low lead aviation fuel prior to departing Hazleton, Pennsylvania.