On August 16, 1993, at 1145 Alaska daylight time, a wheel equipped Aeronca Chief 11AC aircraft, N86361, experienced a loss of engine power while at cruise flight resulting in a forced landing and nose over on muskeg tundra near Kalakette Creek, approximately eight miles west of Galena, Alaska. The pilot in command, who was also the registered owner/operator of the airplane, and his passenger were not injured and the airplane sustained substantial damage. The pleasure flight, operating under 14 CFR Part 91, departed Galena at approximately 1135 and the intended destination was Kalakette Creek. Visual meteorological conditions prevailed and no VFR flight plan had been filed. During a telephone interview with the NTSB investigator in charge on August 16, 1993, the pilot stated that he performed a thorough preflight (including a check of the engine oil quantity and fuel sumps) and engine run up and found the airplane to be in good operating condition. The fuel on board the airplane consisted of two gallons in the rear tank and 10 gallons in the front (main) tank. The takeoff and flight was conducted with the fuel selector on the main tank. While cruising at 850 feet above the ground at an engine rpm setting of 2200, the sound from the engine changed pitch and he observed on the rpm gage a bleed off of approximately 100 rpm. Believing the engine throttle had crept back, he advanced the throttle and the engine stopped suddenly as if it had locked up. There were no metallic sounds associated with the engine stoppage. Post accident attempts by the pilot and passenger to rotate the engine by hand using the propeller were not successful. The pilot reported that he had flown the airplane about 65 hours since acquiring it and had not experienced any problems with the engine. The airplane received an annual inspection in October 1992, and the engine had accumulated approximately 220 hours since undergoing a major overhaul.