On April 11, 1998, at 1000 central daylight time (cdt), a Rodgers Raven, N17JR, operated by a private pilot was destroyed when while in cruise flight, the airplane departed controlled flight and impacted into a field. Visual meteorological conditions prevailed at the time of the accident. The personal flight was being operated under 14 CFR Part 91. No flight plan was on file. Both the pilot and the passenger on board were fatally injured. The local flight originated at Clear Lake, South Dakota, at 0830 cdt. A witness, who saw the airplane just before the accident, said that he heard the airplane approach his farm from the north. "The motor was pretty loud." The airplane was traveling north to south at an altitude of approximately 100 feet above ground level (agl). The airplane came to a position due west of where the witness was standing, and made a flat turn. After the pilot completed the turn, the airplane lost altitude. "It was in a flat attitude as it descended. It didn't seem like the nose [of the airplane] dipped down." The witness said that he lost sight of the airplane when it went behind some trees. He said that he heard the airplane impact on the ground. A Federal Aviation Administration (FAA) inspector examined the airplane wreckage at the site. The airplane was found resting inverted in a plowed field, 4 miles south-southeast of Brandt, South Dakota. The front portion of the airplane, from the propeller aft, to and including the cabin, was broken and crushed inward. The engine was bent to the right. The overhead plexiglass window was buckled outward and broken. The airplane's left wing was bent aft toward the empennage. The flaperon attachment pins on the left wing were bent and broken. The aft fuselage and empennage were intact, but twisted slightly clockwise. Skin wrinkling along the bottom left side of the aft fuselage, just behind the cabin area, was revealed. One of the three propeller blades was broken off at the hub. All three blades showed chordwise scratches. Flight control continuity was confirmed. Examination of the engine, engine controls, and other airplane systems revealed no anomalies. A witness, who spoke to the pilot two weeks prior to the accident, said that the pilot had purchased the airplane in Oklahoma and was hauling the airplane on a trailer. The pilot told the witness that "he only had about an hour's worth of flight time" in the airplane. Another witness, who knew the pilot and the passenger, said that the pilot had brought the airplane to Clear Lake, South Dakota two days prior to the accident. The witness said it was possible that the pilot flew the airplane the day before the accident, but it was more likely that he just did taxi tests. The witness was pretty sure that this was the first time the passenger had flown in the airplane. The results of FAA toxicology testing of specimens from the pilot revealed the following volatile concentrations: 0.09 micrograms per milliliter(ug/ml, ug/g) Bupropion was detected in Blood. 0.025 (ug/ml, ug/g) Bupropion was detected in Liver fluid. The Manager of the FAA Toxicology and Accident Research Laboratory stated that bupropion is a prescribed anti-depressant which can cause some kinds of incapacitation. It is not to be used by persons with seizure disorders. If taken in high doses, Bupropion can induce seizures in four out of every 1,000 persons. Bupropion is being prescribed more to persons who are trying to stop smoking.