On January 16, 1999, at 0950 hours Pacific standard time, an amateur built experimental Hanson Tailwind W-8, N8188, experienced a loss of engine power and impacted terrain near Brown Field, San Diego, California. The aircraft, operated under 14 CFR Part 91, was destroyed. The private pilot/owner/builder and one passenger were not injured. Visual meteorological conditions existed for the local area personal flight and no flight plan was filed. The pilot reported that no abnormalities were experienced with the takeoff and climbout from Brown Field. He stated that they flew through the San Diego Bay visual flight rules (VFR) corridor at 4,500 feet mean sea level (msl) on a 330-degree heading. The pilot reported that they then flew over the east end of Lindbergh field and made a turn to a heading of 085 degrees and descended to 3,500 feet msl. He stated that at this point he noted the oil temperature was above redline. As the descent continued to 3,000 feet msl, the oil temperature decreased slightly. However, the pilot noted that the cylinder head temperature, exhaust temperature, and the pressure "were in the green." At 0945, the engine "clattered to a stop," and the pilot setup for an emergency landing. The propeller was wind milling until he started the landing flare. After landing, the aircraft traveled approximately 20 feet before the main landing gear dug into the soft ground. The aircraft came up on its nose and then vaulted vertically onto its tail, continuing over in a 360-degree turn before coming to rest upright on its landing gear. The pilot stated that both he and his passenger were able to exit the aircraft unaided. The Federal Aviation Administration inspector who examined the engine reported that the number 3 bearing was melted, the number 3 connecting rod had separated, and the engine case was punctured. He further reported that the engine logbook was in compliance with the required condition inspection. The engine had accrued approximately 605 total hours, with the last condition inspection on February 2, 1998. A Lycoming representative stated that this model engine was last manufactured in the 1940's as a ground power unit only and was not intended for aircraft use.