Incident Overview
During a descent, a pilot reduced engine power and felt a "bump" in the throttle. Subsequently, the engine's rpm dropped and power was lost. The pilot established a glide and elected to conduct a forced landing to a nearby airport.
Throttle Malfunction
The pilot reported that moving the throttle had no effect on engine power, and the engine oscillated between idle and full power settings. This erratic behavior persisted throughout the descent.
Inspection Findings
A Federal Aviation Administration (FAA) inspector examined the aircraft after the landing and found that the nut securing the throttle linkage to the carburetor's control lever was missing. The throttle linkage was disconnected at that point.
Maintenance Reference
A review of the manufacturer's maintenance manual indicated that the approved parts for that assembly included a bolt with a fiber-locking nut.
Damage Report
The aircraft sustained substantial damage during the forced landing.