On June 30, 2000, at 2005 Eastern Daylight Time, an Enstrom F28C, N20PZ, was substantially damaged during rollover after landing at the Portage County Airport (29G), Ravenna, Ohio. The certificated student pilot/owner received minor injuries. Visual meteorological conditions prevailed for the solo instructional flight that originated at 29G, about 1950. No flight plan was filed for the flight conducted under 14 CFR Part 91. Several witnesses observed the accident flight and provided statements to the Ohio State Highway Patrol. The statements were in a narrative and question and answer format. One witness observed the accident from the cockpit of his airplane while parked at the approach end of runway 27. According to his statement: "The helicopter was coming from the east end of the runway a little to the north of it. He flew to the south side of the runway. It appeared he was going to touch down there on the grass. When he touched down, it appeared he touched down hard. The helicopter came back up about 2 feet or more off the ground. I don't know if it bounced up or if he brought it up off the ground intentionally. He was still facing the west when it came back off the ground. The craft became unstable and rotated towards the south. The [main] rotor then hit the ground." According to the airplane passenger's statement: "[The] helicopter came in from the east and hovered about 1/4 of the way down the runway. He sat down on the side of the runway in the grass. When he sat down, he landed very hard. The helicopter bounced up from the ground and tilted to the south. The [main rotor] blades caught the ground and pulled it over." According to the statement from the student's instructor: "I was at the NE corner of the airport when I saw [student pilot] in the helicopter as he was about to land. I heard him hit the ground. I turned and saw the helicopter blades hit the ground and the helicopter roll on its side." When asked by the Ohio State Highway Patrol if there was any unusual "engine or propeller noise", the witnesses said there was none. During interviews, the witnesses said they helped the student pilot egress the helicopter. They said he appeared uninjured, but that he mumbled his speech. One witness said, "He was conscious, he knew his name, but he really didn't seem coherent." Another witness said the pilot's right arm hung limply at his side. Emergency personnel who responded to the scene noted the student pilot exhibited right facial droop, weakness on his right side, and slurred speech. In a telephone interview, the pilot's wife said her husband had suffered a stroke. The Safety Board's medical officer reviewed the student pilot's medical records and provided a report. According to the report: "The CAT scan report dated the same day as the accident notes: '1. Cerebral hemorrhage is noted in the left cerebral hemisphere in the left basal ganglia. This measures approximately 2.5 to 3 cm. in size. 2. Intraventricular hemorrhages are noted in both lateral ventricles and the third ventricle'." The weather reported at Akron, Ohio, 10 miles southwest of 29G was clear with 10 miles visibility and calm winds.