On October 11, 2006, approximately 1045 mountain daylight time, a Huff Acro Sport I, N511SH, piloted by a commercial pilot, was substantially damaged when it departed the runway and struck a large rock during landing at Blake Field (AJZ), Delta, Colorado. Visual meteorological conditions prevailed at the time of the accident. The personal flight was being conducted under the provisions of Title 14 Code of Federal Regulations Part 91 without a flight plan. The pilot sustained minor injuries. The local flight originating at Delta approximately 1015. According to the pilot's accident report, a crew was working on the parallel taxiway near the runway edge. The pilot taxied past the construction area and took off on runway 21. After about 30 minutes of flying, the pilot returned to the airport and made some touch-and-go landings. Another airplane entered the traffic pattern and announced he would be landing in the opposite direction on runway 03. The pilot yielded and also landed on runway 03. To avoid the construction crew, he maneuvered the airplane to the left of runway centerline. He noted that his airplane was "a short-coupled biplane," and that forward visibility in a conventional (3-point) attitude was limited. This caused him to get too close to the runway edge, and the left main landing gear went off the left side of the runway and into soft, muddy soil. The airplane swerved to the left, went through some high sage brush, struck a large rock, spun around and nosed down. The airport manager examined the airplane and reported that, in addition to the sheared landing gear, the wing spar was broken.