On June 17, 1996, at 1635 hours Pacific daylight time, a Moore Goshawk 350, N345RM, collided with the terrain after an uncontrolled descent near Livermore, California. The aircraft was destroyed and the pilot received minor injuries. The flight originated in Livermore at 1629 as a personal flight. Visual meteorological conditions prevailed at the time and no flight plan had been filed. The pilot reported that he was in the aerobatic box near Tracy airport flying at an altitude between 4,500 and 5,000 feet msl. He was in the process of tightening his shoulder harness by pushing himself back into his seat with his feet on the rudder pedals. As he pushed with both feet he suddenly felt both rudder pedals go all the way to the floor. The aircraft immediately snap rolled to the right and his attempts at regaining control were unsuccessful. The aircraft continued to spin as the pilot attempted to egress. He was able to successfully parachute from the aircraft, but stated that he injured two of the vertebra in his back on landing. A postaccident inspection of the aircraft by FAA inspectors revealed the left rudder cable was separated at a point 25.5 inches aft of the left rudder pedal swedge. The inspectors reported that both of the 0.125-inch diameter cables appeared to be relatively new and were routed through protective, antichaffing guides from front to rear. The right cable remained intact from the rudder to the rudder pedal. Both sides of the broken cable were examined by Safety Board metallurgists. Their examination revealed that the separation showed that individual wires were necked down or had slant fractures, which they stated was typical of overstress separations. They reported no evidence of corrosion damage, wear, or deformation.