On August 9, 1997, at 2010 mountain daylight time (mdt), a Grumman-American AA-5, N7148L, piloted by a private pilot, collided with the surface of Lake Sharpe, about 7 miles northwest of Lower Brule, South Dakota. Visual meteorological conditions prevailed at the time of the accident. The 14 CFR Part 91 flight had been operating on a VFR flight plan. The pilot was fatally injured and was recovered 5 days after the accident. The flight departed from Sioux City, Iowa, exact time unknown. A witness fishing on the lake said the airplane passed over him at a low altitude. He said there was no engine noise as the airplane passed overhead. According to the witness, the airplane nosed over onto its top as it collided with the water. Shortly after nosing over, the airplane sank out of sight, according to the witness. The witnesses and rescue personnel reported that no debris, fuel, or oil slicks were observed. According to the Hughes County, South Dakota, Sheriff's Department incident report, the accident pilot had purchased fuel in Sioux City, about 1714 central daylight time (1614 mdt). The sheriff's report states that a direct line course between the pilot's departure point and intended destination, Priest River, Idaho, goes directly over the lake in which the airplane crashed. The distance between Sioux City and the accident site was 177 nautical miles. Before departing Sioux City, the pilot topped N7148L's fuel tanks off with 22 gallons of 100 Low Lead aviation gasoline. A business partner and flight instructor of the pilot said he would normally operate the airplane's engine at 2,400 RPM during cruise flight. According to the accident airplane's flight manual, the airplane had a usable fuel of 37 U.S. gallons. The airplane's cruise range varied with altitude at the 2,400 RPM power setting. The pilot's operating handbook showed a no-wind range between 586 and 625 miles for the power setting. The airplane was not retrieved due to the water conditions. The Federal Aviation Administration's Civil Aeromedical Institute toxicological report showed positive for ethanols that were result of decomposition. The pilot's autopsy was conducted by Dr. Brad B. Randall on August 15, 1997, at LCM Pathologists, P.C., in Sioux Falls, South Dakota.