On September 24, 2002, at 1130 central daylight time, a Cessna 152, N46656, registered to and operated by Middle Tennessee State University, ditched into Watts Bar Lake near Spring City, Tennessee, during a simulated loss of engine power. The instructional flight was operated under the provisions of Title 14 CFR Part 91 with no flight plan filed. Visual weather conditions prevailed at the time of the accident. The airplane sustained substantial damage, and the certified flight instructor and the private pilot were not injured. The flight departed Knoxville, Tennessee, at 1100, on September 24, 2002. While conducting an instructional flight and flying at 2500 feet, the certified flight instructor turned the fuel selector to the off position to simulate a loss of engine power. The certified flight instructor's attempts to restore engine power failed, and he elected to ditch the airplane in Watts Bar Lake. Upon contact with the water, the airplane flipped violently and sank in 40 to 60 feet of water. After the certified flight instructor and the student pilot exited the airplane, both were rescued by a seaman in a boat. The Middle Tennessee State University Cessna 152 Standardization Manual states that the instructor may simulate an engine failure by reducing the throttle to idle. The Airplane Flying Handbook (FAA-H-8083-3) concurs with this procedure and notes that the flight instructor should simulate an emergency landing by retarding the throttle and calling "simulated emergency landing". The Airplane Flying Handbook also states that "during all simulated emergency landings, the engine should be kept warm and clear". The airplane was not recovered for examination. The certified flight instructor did not report a mechanical problem with the airplane before the simulated loss of engine power.