Incident Overview
A pilot conducted a post-maintenance check flight of an aircraft after its annual inspection had been completed the previous day. During the inspection, the three engine control cables had been replaced. While cruising, the engine lost power, prompting the pilot to attempt a glide to an emergency landing. The pilot overshot the 3,100-foot-long runway and exited the departure end.
Post-Incident Examination
After the engine cowling was removed, it was found that the bolt connecting the throttle control to the throttle body actuator arm was missing. The bolt was discovered in the bottom of the cowling, but the corresponding nut was not located. Further examination revealed that the bolt did not comply with an applicable Airworthiness Directive.
Pilot Observations
The pilot opined that after the throttle control separated, the engine may not have reduced to idle power. He suggested that this partial engine power could have contributed to the landing overshoot. Additionally, the pilot stated that he was wearing a headset during the flight and could not hear the engine well enough to detect a partial power condition.