The experimental airplane was on a test flight when it impacted terrain following an emergency landing attempt. The airplane was certified as an experimental airplane for crew training. The airplane's aileron spring cartridge and rudder-aileron interconnect had been removed for the test flight. The airplane was loaded with ballast to provide an aft center of gravity with stall tufts attached to both wings. During the test flight, the company test pilot declared an emergency and reported a flight control problem while maneuvering. Radar data indicates that 10 seconds prior to the declaration of an emergency by the test pilot, the aircraft was in a stall phase of flight. Postaccident inspection revealed that the right aileron exhibited evidence of jamming with its wing cove/skin. In postaccident testing of a similar SR20, a manual input pilot force was applied to the side yoke control by a Cirrus Design Corporation (CDC) test pilot. A maximum load of 85 pounds was achieved by the test pilot by leaning forward and applying both hands on the side yoke control. The control input could not be held indefinitely due to muscle fatigue. During the control input, the right aileron was deflected 11 degrees with the left aileron clamped at the inboard rib. CDC test pilots were not graduates of civilian or military flight test schools. The test pilot was not equipped with a personal parachute. A gusting crosswind of approximately 16 knots was present on the selected landing runway. The airplane's maximum demonstrated crosswind component was 19 knots. All runways were available at the time of the accident. CDC was not monitoring radio communications with the accident pilot during the test flight.

The National Transportation Safety Board determines the probable cause(s) of this accident as follows:

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