La Cholla Airpark Airport
Aircraft Accident/Incident Report

Tucson, Arizona 85701
Sunday, November 20, 2005 17:10 MST

The airplane landed hard during a forced landing following a loss of engine power in cruise flight. After a normal departure the airplane climbed to about 4,800 feet mean sea level (msl). The pilot noticed an audible difference in the engine operation, as if it were making intermittent pauses. As he was flying back to the airpark the engine continued to operate abnormally and began to make severe "popping" sounds. Despite the pilot's efforts, the engine failed to respond to his troubleshooting attempts and subsequently lost power. The airplane touched down about 1/3 down the runway, contacting the surface hard. A post-accident inspection preformed by a Federal Aviation Administration certificated mechanic who also holds an Inspection Authorization (IA) revealed that the mixture cable had disconnected at the carburetor. Specifically, the mixture linkage was separated where the cable adjoins the mixture control arm. The pilot and mechanic opined that the separation of the linkage would decrease the fuel supply and alter the fuel/air ratio, resulting in a subsequent loss of power. The airplane had last undergone an annual inspection 44 flight hours prior to the accident; the cable was last inspected at that time. The pilot stated that due to the location of the mixture cable, the mechanic would have to remove the cable from the throttle arm to inspect it in its entirety. The airplane's service manual states that during every 100-hour inspection the mechanic should inspect the mixture cable for, "travel and operating condition."

the separation of the mixture cable at the carburetor control arm, which resulted in a loss of power, and maintenance personnel's inadequate inspection of the airplane during the last annual inspection.