On June 22, 2016, about 1130 central daylight time, a Cessna 182P airplane, N9434M, was substantially damaged following a forced landing near Humansville, Missouri. The commercial rated pilot and passenger sustained minor injuries. The airplane was registered to and operated by a private individual under the provisions of 14 Code of Federal Regulations Part 91 as an air race. Visual meteorological conditions prevailed for the flight. The cross-country flight departed the Dexter B Florence Memorial Field Airport, Arkadelphia, Arkansas, and was en route to the Skyhaven Airport, Warrensburg, Missouri.The pilot reported that while in cruise flight at 500 ft above ground level (agl) for about 1 hour and 42 minutes, the engine surged and lost partial power. The pilot attempted to restore power by adjusting the throttle, propeller, mixture, and carburetor heat. Unable to restore power, the pilot diverted to the closest airport. The engine did not respond, and the airplane sank through 250 ft agl, so the pilot conducted a forced landing to a field. The landing surface was hard and deeply rutted resulting in the separation of the nose wheel and the airplane nosed over. The fuselage was substantially damaged during the forced landing. The airplane was examined by the responding Federal Aviation Administration (FAA) inspector and a representative from Textron Aviation, no preimpact anomalies were detected with the airframe. Data from the airplane's JPI engine monitoring system was downloaded by the National Transportation Safety Board laboratory. A review of the data revealed that about 1120, the fuel flow fluctuated. Two minutes later, the fuel flow decayed from about 19 gallons per hour to a final value of 2.7. A test run of the airplane's engine was conducted by the FAA inspector, with assistance from a local airframe and powerplant mechanic and a representative from the engine manufacturer. A new propeller, engine mounts, throttle cable, and battery were installed on the airplane. An external fuel supply was plumbing into the left wing root. The engine was primed once and started on the first attempt. A magneto check was performed and the propeller pitch cycled. The throttle was advanced to full power and the engine achieved approximately 27 inches of manifold pressure; the tachometer was inoperative, so the maximum rpm could not be determined. The FAA inspector noted that a fuel line from the gascolator to the carburetor had a tight 160° turn, but the fuel line did not appear "kinked" to impede fuel flow. Shop air was applied to the fuel lines and no obstructions were found. A review of the Carburetor Icing Probability Chart in the Federal Aviation Administration Special Airworthiness Information Bulletin CE-09-35, Carburetor Icing Prevention found that the airplane was operating in an area conducive for the formation of icing at glide and cruise power. The reason for the loss of engine power could not be determined.