On February 2, 2013, about 1400 Pacific standard time, a Cessna 305A, N342FS, experienced a runway excursion at Camarillo Airport, Camarillo, California. The pilot/owner was operating the airplane under the provisions of 14 Code of Federal Regulations (CFR) Part 91. The commercial pilot and a pilot-rated passenger were not injured; the airplane sustained substantial damage. The local personal flight departed Camarillo at 1300. Visual meteorological (VMC) conditions prevailed, and no flight plan had been filed.The pilot reported that the preflight detected no anomalies with the airplane. The departure and local area flight had been uneventful. The three-point landing was normal in minimal wind. Immediately upon touchdown, the pilot felt an extreme tail wheel vibration, and the airplane abruptly made a sharp left turn. The airplane veered off the runway, and the right main landing gear collapsed. The right wing, right aileron, right landing gear box, horizontal stabilizer, and right elevator sustained substantial damage. The pilot noted that post flight inspection revealed that the right rudder cable had broken. Examination by a Federal Aviation Administration inspector revealed that the rudder control cables for the front and back seats, which extend from the rudder pedals to the rudder control horn, had separated about 14 inches from the rudder pedals. This was in the vicinity of the collapsed right main gear attachment point. No observations were made that could account for the tail wheel vibration on touchdown. The National Transportation Safety Board Materials Laboratory examined the rudder control cables. The specialist conducting the examination determined that both cable fractures were consistent with overstress; no evidence of preexisting defects, such as corrosion or fatigue, was found.