LAX07IA093 · Columbia Aircraft LC41-550FG

The pilot experienced a "check attitude" annunciator warning related to the airplane's autopilot while in cruise flight in his 8-month-old airplane. The pilot responded to the warning by initially cycling the autopilot off and on. He also attempted to correct the increasing left bank of the airplane, but movement of the aileron control stick was restricted. The stick turned to the right but its movement stopped at the center position. The pilot further described the anomaly by stating that "the yoke felt as if it were hitting something very solid." It felt like the yoke "was hitting a metallic stop." Despite his best efforts at applying right aileron roll control inputs (even using both hands), he was not able to move the control stick right of the neutral aileron (wings-level) position. The airplane reached an approximate 90-degree left bank angle before his application of full right rudder control inputs returned it to level flight and he reacquired control. At the time, the pilot was approaching his home base airport, and he decided to land. After two approaches that terminated in go-arounds, the pilot successfully landed and taxied to his hangar. While taxiing, the pilot tried to get the aileron to move freely upon application of stick pressure. Also, after he parked the airplane he tried to move the aileron with his hands. When he moved the stick to the right, it would stop at the neutral position. Before further flight, the airplane and its autopilot systems were examined. No anomalies were found with the autopilot or related systems. Under the Safety Board's directed inquiry, the aileron binding event was confirmed during the FAA's and participants' physical inspection of the right wing's linear bearing, through which the actuating control rod is routed. Manufacturing-related foreign object debris (FOD) was found on the bottom of the inboard side of the linear bearing housing. Previously, reports had been received of flight control binding events, but the manufacturer had failed to so notify the FAA, pursuant to regulations. The manufacturer responded by issuing a mandatory service bulletin, and the FAA responded to the incident by issuing an airworthiness directive to address identification and prevention of similar control binding events.

Verbatim NTSB analysis and probable cause from the NTSB dataset