On September 19, 2011, about 0930 eastern daylight time, an experimental amateur-built Heinlein GH125, N79GH, was substantially damaged when the right main landing gear collapsed during landing roll at Okeechobee County Airport (OBE), Okeechobee, Florida. The non-certificated pilot was not injured. The airplane was registered to the pilot and operated under 14 Code of Federal Regulations Part 91. Visual meteorological conditions prevailed, and no flight plan was filed for the local personal flight, which originated at OBE. After landing and while taxiing to the ramp area, the right main landing gear collapsed, the airplane turned 180 degrees, and came to rest on the runway. The right wing was substantially damaged during the accident sequence. A post accident examination of the main landing gear by the pilot revealed that a bolt in the right main landing gear had fractured. The pilot, age 72, had previously held a student pilot certificate which expired in 2003. His most recent FAA third-class medical certificate was issued in June of 2001. He reported 300 total flight hours, of which, 70 hours were in the same make and model as the accident airplane. In addition, he reported that he had flown 5 hours in the last 30 days. According to FAA records, the airplane was manufactured in 1993, and registered to the pilot in 2007. It was a two-seat, high-wing monoplane, which had conventional tailwheel landing gear. It was equipped with a Lycoming O-290 series, 130-horsepower engine. The most recent condition inspection was performed on September 28, 2010, by the pilot, who did not hold a repairman certificate for the airplane. The right main landing gear bolt was examined by the Safety Board Materials Laboratory. According to the Laboratory's factual report, based on the deformation of the bolt shank and the fracture surface features, the bolt fractured in overstress due to concomitant shear and bending stresses. According to the pilot, the right main landing gear bolt had accumulated 265 hours of total time in service. In addition, he stated that he might have landed the airplane "hard" on the day of the accident and also a few times prior to the accident.