On June 18, 2009, about 2115 mountain daylight time, a Bellanca 17-31ATC, N14797, experienced a collapse of the left main landing gear during the landing roll at Roosevelt Municipal Airport, Roosevelt, Utah. The commercial pilot, who was the sole occupant, was not injured, but the airplane, which is owned and operated by the pilot, sustained substantial damage. The local 14 Code of Federal Regulations Part 91 personal pleasure flight, which departed Roosevelt Municipal Airport about 15 minutes earlier, was being operated in visual meteorological conditions. No flight plan had been filed. According to the pilot, this was a brief local flight to check the operation of the turbocharger, which had just come out of maintenance. After the flight around the local area, the pilot returned to the airport for a full stop landing. Reportedly, he made a normal flare and touchdown, and the first 1,000 feet of the landing roll was uneventful. The left main landing gear green DOWN light went out, and the red landing gear TRANSITION warning light came on, and the left main gear retracted. After the gear retracted, the airplane exited the left side of the runway, and collided with rough terrain. This sequence resulted in damage to the left wing, and bending of the fuselage structure. A post- accident inspection of the left landing gear extension and retraction system by a Federal Aviation Administration (FAA) Airworthiness Inspector determined that the bolt connecting the hydraulic gear actuator rod to the gear leg support had failed. Further inspection revealed that over a period of time the bolt hole in the gear leg support had worn to a point where it had become elongated to about twice its original size (see photo in the public docket for this accident). According to the FAA inspector, the elongation of the hole, and the looseness it would have created, should have been detected during at least the last couple of annual inspections.