On March 26, 2005, about 0822 mountain standard time, a Lee/Geiser Nieuprt17, N124FG, encountered a gusty crosswind during landing rollout on runway 22R at the Chandler Municipal Airport, Chandler, Arizona. The airplane swerved off the runway, ground looped, nosed over and was substantially damaged. The private pilot owned and operated the experimental-homebuilt airplane, and he was not injured. Visual meteorological conditions prevailed, and no flight plan had been filed for the personal flight. The flight was performed under the provisions of 14 CFR Part 91, and it originated from Chandler about 0810. The pilot reported to the National Transportation Safety Board investigator that when he took off the local wind was nearly calm. However, during landing he encountered a wind gust that came out of nowhere, and he lost control of his conventional gear biplane. The pilot estimated that the gust was from 330 degrees at over 10 knots. Eight minutes later, at 0830, Chandler's reported weather indicated the wind was from 300 degrees at 12 knots, and no gusts were reported. The sky was clear, and the visibility was 40 miles. Runway 22R is 4,401 feet long and 75 feet wide. The pilot did not report experiencing any mechanical malfunction or failure with the airplane.