On March 29, 2001, at 1556 mountain standard time, a Piper PA-18-150, N9464D, sustained substantial damage when it ground looped and exited the side of the runway during takeoff roll at Walker Field, Grand Junction, Colorado. The student pilot and sole occupant received minor injuries. The flight was a local area student solo instructional flight operating under Title 14 CFR Part 91 and no flight plan was filed. Visual meteorological conditions prevailed. According to information provided by air traffic control, the takeoff was being made on runway 11. The observed wind was from 020 degrees magnetic heading at 13 knots, which is a direct crosswind. (No crosswind limit is established for aircraft certificated under 14 CFR Part 23.) When the aircraft exited the side of the runway, collision with rough terrain caused the right wing and right main landing gear to separate from the aircraft. A review of the pilot's flight time and medical records revealed he had a total of 70 hours of flight experience all in the accident aircraft make and model, and he was denied a medical following his examination on July 7, 1999.