On June 7, 2002, approximately 1700 mountain daylight time, a Beech A35, N8735A, registered to and operated by the pilot, was substantially damaged when it landed wheels-up at Mondell Field, Newcastle, Wyoming. The private pilot, the sole occupant aboard, was not injured. Day visual meteorological conditions prevailed, and no flight plan had been filed for the local personal flight being conducted under Title 14 CFR Part 91. The flight originated at Newcastle approximately 1600. The pilot had just purchased the airplane, and the purpose of the flight was to practice maneuvers outlined in the commercial pilot practical flight test guide. After practicing various maneuvers in the practice area, he returned to the airport and performed different types of takeoffs and landings on runway 31. The pilot said the airport's AWOS (automated weather observation station) then reported a wind shift, and he made an approach to runway 13. He forgot to lower the landing gear and landed wheels up. According to a Raytheon Aircraft Company spokesman, the airplane is equipped with an audible landing gear warning system that activates whenever power is reduced below 12 inches of manifold pressure and the landing gear is still retracted. The pilot said he didn't know if his airplane was so equipped and, if it was, he did not hear the warning horn prior to touchdown. According to a repairman who examined the airplane, three bulkheads aft of the firewall were buckled and the wing spar was bent when the extended flaps contacted the runway.