On August 22, 2009, at 1210 eastern daylight time, a Cessna T210M, N732MM, was substantially damaged during landing at Dalton Municipal Airport (DNN), Dalton, Georgia. The certificated private pilot and passenger were not injured. Visual meteorological conditions prevailed, and no flight plan was filed for the local personal flight conducted under the provisions of 14 Code of Federal Regulations Part 91. According to the pilot, when the airplane was in traffic pattern for runway 32, he lowered the landing gear and noticed the right landing gear light was not illuminated. He cycled the landing gear twice; however, the right landing gear light still would not illuminate. The pilot initiated a climb and "pumped the gear manually." The landing gear appeared to all be down and locked; however, the pilot radioed to personnel at the airport (on the UNICOM frequency) and asked them to check the landing gear as he performed a fly over. Personnel reported to the pilot that the landing gear all appeared down. The pilot continued the landing and as the airplane touched down on the runway, the right landing gear collapsed. The airplane swerved to the right and traveled off the side of the runway. Runway 32 was a 5,603 foot-long and 98 foot-wide, asphalt runway. Examination of the airplane by a Federal Aviation Administration inspector revealed substantial damage to the horizontal stabilizer. Further examination of the landing gear system revealed the right main landing gear actuator downlock spring was distorted. The most recent annual inspection was completed on November 4, 2008. According to the mechanic, the landing gear was inspected at that time with no anomalies noted.