Repeated attempts to contact the pilot were unsuccessful. According to the Federal Aviation Administration (FAA) inspector, the airplane was taking off in a southbound direction from a private dirt strip about 16 miles southwest of the Sheridan County Airport (SHR), Sheridan, Wyoming. The pilot reported to the FAA inspector that the airplane had cleared 50 foot trees and was about 100 feet above the ground, when the right quartering headwind changed and the airplane was "blown out of the air." The pilot was able to level the airplane before the airplane stuck the ground and cartwheeled, coming to rest in a nose down attitude at a tree. The pilot stated that there were no mechanical problems with the airplane. The pilot was not able to recall the wind velocity. Witnesses in the area reported that it was windy. Wind information recorded by SHR indicated that the winds were from 140 degrees at 9 knots gusting to 15 knots.