On September 2, 2004, at approximately 0900 mountain daylight time, an Aviat A-1, N6XJ, piloted by a private pilot, was substantially damaged when it nosed over during a landing 12 miles southeast of Greeley, Colorado, along the Platte River. Visual meteorological conditions prevailed at the time of the accident. The personal flight was being conducted under the provisions of Title 14 CFR Part 91 without a flight plan. The pilot reported no injuries. The cross-country flight originated from Longmont, Colorado, at approximately 0800. According to the accident report submitted by the pilot, he had touched down short of his intended landing site and was rolling out when the nose wheel became stuck in the sand. The pilot stated that the landing surface was a "private unimproved site." The airplane nosed over and came to rest inverted near the river. Both wing struts were bent, three ribs in the right wing were crushed and the rudder fin and vertical stabilizer were crushed.