The pilot stated that as he turned the airplane onto final for runway 14, the winds shifted from a crosswind to a tailwind. At touchdown, there were 1,800 feet remaining of the 2,780-foot runway. The airplane skidded on the grass, overran the runway end, and collided with a shallow ditch. The nearest weather reporting station, 10 nautical miles away, reported that at the time of the accident, winds were variable at 9 knots, gusting to 12 knots. The pilot did not report any mechanical or flight control anomalies. Examination of the airplane by a Federal Aviation Administration inspector revealed that the fuselage was buckled, and no flight control anomalies were noted during the examination.