Incident Overview
During a pre-takeoff run-up, a pilot performing flight control checks encountered an aileron control failure. The pilot was unable to obtain left aileron up movement. Subsequent inspection determined that the left aileron had only 4 degrees of upward travel, compared to the normal range of 20 degrees plus or minus 2 degrees.
Inspection Findings
Further examination revealed that one of the aileron control bellcrank stop bolt/jam nut assemblies was loose. This allowed the stop bolt to rotate out of its threaded boss, restricting aileron movement. The three other stop bolt/jam nut assemblies on the same aircraft were also inspected and found to be loose.
Aircraft Information
The affected airplane was a 1999 model with serial number 25 and had accumulated approximately 11 total flight hours at the time of the incident.
Manufacturer and Regulatory Actions
In response to the incident, Cessna Aircraft Company issued Special Service Project SSP99-27-02. On June 21, 1999, the Federal Aviation Administration (FAA) issued Airworthiness Directive (AD) 99-13-04, which became effective July 13, 1999. The AD requires inspecting the left and right wing aileron control bellcrank stop bolts and lock nuts for flush and tight contact with the surface of the threaded boss on each end of the yoke assemblies, and accomplishing follow-on and corrective actions as applicable.