Incident Details
A Cessna 650 encountered a right wing aileron cable failure while in cruise flight at flight level 390, approximately 200 miles southeast of Rapid City, South Dakota. The pilot in command reported that with the autopilot engaged, the airplane initiated a gentle roll to the right. After disengaging the autopilot, approximately 40 degrees of control wheel deflection to the left was required to maintain level wings.
Pilot Response
The pilot noted that the right aileron did not appear to move in response to control wheel inputs, while the right roll control spoiler functioned normally. All left-side control surfaces operated as expected. The pilots consulted the control malfunction checklists but observed no changes in the aircraft's handling. They decided to continue to their destination and executed a full-flap landing at Rapid City Municipal Airport without further incident.
Maintenance Findings
During post-flight inspection, maintenance personnel discovered a completely broken right outboard aileron cable. The cable, part number 6260106-25, was subjected to metallurgical examination. The wire strands exhibited sheared and cut ends consistent with pinching, as if the cable had dislodged from its large-diameter pulley and been pulled over a small radius. Only a few tensile cup cone fractures were observed, indicating that nearly all wire strands were sheared or cut prior to the final tensile separation of the remaining strands.