On October 1, 2001, about 1700 mountain daylight time, a Cessna 172, N3910F, was destroyed when it collided with terrain near Lindsay, Montana. The airplane was owned by the pilot, and was being operated as a personal/pleasure flight under the provisions of Title 14, CFR Part 91, when the accident occurred. The private pilot, the sole occupant of the airplane, received serious injuries. Visual meteorological conditions prevailed, and a visual flight rules (VFR) flight plan was filed and activated for the cross-country flight. The flight originated from Glendive, Montana (GDV), approximately 30 minutes prior to the accident. The pilot's planned destination was Helena, (HLN), Montana. During a telephone interview with a NTSB investigator on October 1st, the pilot reported that he was adjusting the airplane's radio while in a cruise configuration at an altitude of 300 feet above ground level (AGL). The pilot reported in a written statement that the communications radio on the copilot side was making noise due to airflow from the vent, and he was attempting to adjust its position just prior to the accident. He reported that he remembered "pulling up" just before the airplane collided with terrain. The pilot stated that he was unable to recall any of the detailed events leading up to the accident. The pilot reported in a written statement that prior to the flight, he amended the flight plan cruise altitude from 6500 feet to 4500 feet. The pilot reported on the Pilot/Operator Aircraft Accident Report Form no mechanical malfunction or failure at the time of the accident. The automated weather observation at Glendive, Montana (GDV), at 1655 reported winds from 160 degrees at 6 knots, 10 statute miles visibility, and clear skies. Glendive is approximately 25 nautical miles west of the accident site.