On May 18, 2000, about 1620 eastern daylight time, a Cessna A150M, N9843J, registered to a private individual, operating as a Title 14 CFR Part 91 personal flight, crashed in a field in the vicinity of Gainesville, Georgia, following a reported loss of engine power. Visual meteorological conditions prevailed and no flight plan was filed. The airplane received substantial damage and the private-rated pilot and a passenger were not injured. The flight originated from Lawrenceville, Georgia, about 30 minutes before the accident. According to the pilot, he and a friend were sightseeing in the Lake Lanier area at 3,500 feet msl, when they experienced a partial loss of engine power. He completed the checklist items for "engine failure during flight", but lost all engine power, necessitating a forced landing to a vacant field. The touchdown was harder than expected due to upsloping terrain in the direction of the landing. According to the FAA inspector's report, the wreckage was transported to an engine overhaul facility where the Continental O-200A engine, serial no. 253638-A-48, was removed from the airframe, N9834J, and operated with FAA oversight. The fuel used for the postcrash engine run was the same fuel aboard at the time of the accident. The engine started smoothly and operated normally at various power settings with no malfunctions. No evidence of any fluid leakage was noted. Reference to carburetor icing probability charts reveals that an ambient temperature of 84 degrees F and a dew point temperature of 54 degrees F, as reported by the Gainesville, Georgia, AFSS, for the time period of the accident would put the flight's probability within the region labeled, " visible icing at cruise power" and also within the more restrictive region, "serious icing at glide power". A copy of the chart is included as an attachment to this report.