On May 14, 1998, at 1800 hours Pacific daylight time, a Piper PA-22-160, N198TP, registered to the Aircraft Owner's and Pilot's Association (AOPA), experienced a total loss of engine power in the traffic pattern at the uncontrolled Clarksburg Airport, Clarksburg, California. Unable to glide to the runway, the commercial pilot made a forced landing in a soft field and the airplane nosed over. The airplane was substantially damaged, and the pilot received minor injuries. Visual meteorological conditions prevailed at the time of the personal flight, and no flight plan was filed. The flight originated from Sacramento, California, at 1750. The pilot reported that prior to taking off for the planned 10-minute-long flight both fuel tanks contained over 5 gallons of fuel, and all airplane systems were functioning normally. The pilot arrived at Clarksburg and entered the traffic pattern. Carburetor heat was applied, the throttle was retarded, and the airplane descended. The pilot further stated that after turning onto the base leg he moved the throttle forward to increase engine power, and the engine "blubbered and totally lost power." The Federal Aviation Administration (FAA) coordinator responded to the accident site and examined the wreckage. The FAA reported it examined the powerplant, induction system, engine controls, and magnetos. The ignition switch and the carburetor were also functionally examined. No evidence was found of any mechanical malfunctions.