What happened
While cruising at 12,500 feet, the pilot of the aircraft decided to disengage the autopilot to maneuver over mountainous terrain. After pressing the trim-disengage button on the control yoke, the airplane began rolling uncontrollably to the left and right. The pilot managed to steady the aircraft using the rudder and initiated a half-standard rate left turn.
Upon attempting to roll the aircraft to the right, the pilot encountered flight controls that were difficult to manipulate. Subsequent turns confirmed that this difficulty persisted. The pilot noted that the control stiffness increased as airspeed was reduced.
Following these events, the pilot declared an emergency with air traffic control and began a descent toward the nearest airport. Because the pilot was unable to locate the airport, he elected to perform a wheels-up landing on a snow-covered field. The wheels up landing resulted in substantial damage to the inboard left wing and the bottom left side of the forward fuselage; the pilot was not injured.
The investigation
An examination of the aircraft was conducted to identify any mechanical issues that could account for the stiff flight controls. The inspection revealed no anomalies that would explain the difficulty in manipulating the controls.