The pilot reported that during the landing flare, about 1 to 2 feet above the ground, the airplane drifted right. The right main landing gear then contacted a snowbank along the right side of the runway, which caused the airplane to nose over. The airplane subsequently came to rest inverted adjacent to the runway. Examination of the airplane by a Federal Aviation Administration inspector revealed substantial damage to the wings and fuselage. The inspector did not observe any preimpact mechanical malfunctions with the airplane, nor did the pilot report any. The recorded wind at a nearby airport, about the time of the accident, was variable at 6 knots.