N115CD

HISTORY OF FLIGHT

On March 23, 1999, at 1328 central standard time, a Cirrus Design SR20, N115CD, operated by the Cirrus Design Corporation (CDC), was destroyed on impact with terrain following an emergency landing attempt on runway 27 (10,152 feet by 150 feet, dry concrete) at Duluth International Airport (DLH), Duluth, Minnesota. Prior to the landing attempt, the pilot had declared an emergency and reported a flight control problem while maneuvering. Visual meteorological conditions prevailed at the time of the accident. The 14 CFR Part 91 local test flight was not operating on a flight plan. A company test pilot, the sole occupant, was fatally injured. The flight originated from DLH at 1312.

At 1312:17, the Duluth Air Traffic Control Tower, Local Control (LC), transmitted, "cirrus one one five charlie delta duluth tower runway two seven you're cleared for take off right turn north bound approved the wind three two zero at one three".

The National Transportation Safety Board's (NTSB's) Recorded Radar and Aircraft Performance Study which is included in this report, indicates that N115CD climbed to an altitude of 6,500 feet msl at 1320:27, descended to an altitude of 6,300 feet msl at 1320:51, and returned to an altitude of 6,500 feet msl at 1321:15 which was then followed by a continued descent. At approximately 1322:10, the radar data shows a deceleration of airspeed to 52 knots which was then followed by a continued increase. According to CDC representatives, the typical scenario during stall testing would be to accomplish "aileron maneuvers" to determine hinge moments by first "tracing back and forth" prior to entering the stall series, which would be performed at a minimum altitude of 6,000-6,500 feet. Also, deep stall testing involves aggressively and repeatedly moving the control yoke left and right during the stall to characterize the SR20's deep stall roll stability.

At 1322:20, N115CD, transmitted, "---ah tower cirrus one one five charlie delta emergency aircraft about five miles north of the field." Radar data indicates that N115CD was at an approximate altitude of 5,000 feet msl, 167 knots airspeed, and 155 knot ground speed.

At 1323:46, N115CD, transmitted, "loud and clear emergency aircraft two miles north of the field flight control problems i'll be turning in bound trying to land on two seven."

At 1327:23, N115CD, transmitted, "--- --- cirrus one one five (keyed mike)." There were no additional transmissions by N115CD.

In a written statement, the executive vice president of CDC reported the following: "The morning of March 23, after what I believe was the first flight of the day, I had told both flight OPS [operations] and the flight maintenance crew that I wanted the squawks to be taken care of as quickly as possible between flight hops. The first concern that I wanted taken care of was the fact that our ailerons were heavy and that the autopilot could not overcome the friction and turn the airplane, I talked to [the accident pilot] and flight maintenance and had them remove the spring cartridge and the rudder aileron interconnect from the aileron control system. What we were looking for was isolating the problem from an aerodynamic problem or a rigging problem. After lunch I returned at about 12:30 PM and the airplane was outside with [maintenance] going over the logbook with [the accident pilot]. I felt, and believe [the accident pilot] also felt that this was a very routine flight. After [the accident pilot] had taxied away I got into the 182 to go for a short flight around the area. I was taxiing out to runway 27 when [the accident pilot] had flown by. The take off and climb out appeared normal. I took off and flew north over Fish and Island lakes. I was just north of Boulder Lake when I [heard the accident pilot] call and declare [an] emergency. He stated he was five miles north and had a control problem. I turned back to the airport. When [the accident pilot] made his second call I was just north of Rice and he called two miles north. I couldn't see [the accident pilot] but I called him to tell him I was just north of his position if he needed me to come in and take a look at the airplane. He did not answer. The tower did not answer. The tower stated that [the accident pilot] was turning final. I stayed just north of the pattern until the tower stated to the ground units that he had gone down in the prison. I then flew over the prison as the ground safety crew was approaching the sight. I did not see the plane as I flew over. I then circled to land..."

A witness reported seeing the airplane overshoot runway 27, track along taxiway A, and enter into a steep bank returning to runway 27. The airplane began tracking over runway 27 at an altitude of 5-15 feet above the runway with its nose yawed approximately 20 degrees to the right. The witness stated the aircraft performed a go-around at the midfield position and made a left 70 degree turn with a bank angle of about 90 degrees, when the airplane's nose sliced down about 20-40 degrees.

A second witness located at the U.S. Department of Justice Federal Prison camp, reported the following in a written statement: "On Tuesday, March 23, 1999, at 1:29 pm, I was standing outside the administrative building when I heard a planes engine throttle up to what appeared to be full power. I observed the white plane appear from behind the airport hangers at an approximately 60 degree angle upward. After the plane reached approximately 400-500 feet, the plane leveled his lift and appeared to wobble sideways. The wind appeared to have been a factor and the plane started to bank toward the left. The plane appeared to be maintaining his altitude still in a hard bank to the left, with the engine running at a lower speed. Once the plane appeared to have been over Dorm 211, the planes pitch changed to a steeper decline or nose dive toward the ground, still with the left wing tilting downward. The plane appeared that it would reach the point of impact behind the administrative building or possibly the adjacent parking lot. I immediately began running toward the rear of the building when I lost sight of the plane for approximately 5 seconds. I did not see the point of impact but heard the plane crash into the ground. When I turned the corner of the building, I observed the plane had struck the ground near the Special Housing Unit and slid striking the handicap railing on the walkway leading into the Health Service Unit, then came to rest against the far side of the building..."

PERSONNEL INFORMATION

The 33 year old pilot was hired by CDC, on June 6, 1996, as the Director of Flight Operations. During his employment at CDC, he served as a flight test pilot during initial and final test phase of the SR20's development and production. The pilot also held an airline transport pilot certificate with a multiengine land rating and a commercial pilot certificate with single engine land and sea ratings. He received a second class medical certificate on July 16, 1998 with no limitations. Federal Aviation Administration (FAA) records indicate that the pilot was involved in a general aviation accident on May 21, 1990 and a general aviation incident on May 20, 1998. He accumulated a total time of 1,311 hours as a United States Air Force Pilot (Air National Guard) and had last flown an F16 on March 19, 1999. CDC reported that the pilot accumulated a total flight time of 741.8 hours in the SR20. No records received indicated the pilot had any formal training as a test pilot.

AIRCRAFT INFORMATION

N115CD, a CDC SR20, serial number 1001, was a four-place single engine airplane powered by a six-cylinder, 200-horsepower, Teledyne Continental Motors model IO-360-ES(6), serial number 357110, with a three-bladed Hartzell constant speed propeller, serial number JC2A. N115CD was issued an experimental airworthiness certificate for crew training on March 22, 1999. The aircraft had been flown on three flights preceding the accident for a total flight time of 5.1 hours. The total airframe time at the time of the accident was 5.4 hours.

The SR20 utilizes conventional flight controls for aileron (roll axis), elevator (pitch axis), and rudder (yaw axis). The control surfaces are pilot-controlled through either of two single-handed side control yokes mounted beneath the instrument panel, and rudder pedals. The control system utilizes a combination of push rods, cables, bell cranks, and spring cartridges for control of the surfaces. Roll trim and pitch trim are available through an electric button on the tip of each "side stick" control yoke; however, the roll trim cartridge which is connected to the roll trim actuator had been disconnected on the accident airplane just prior to the accident flight. A bungee rudder-aileron interconnect is installed in SR20 aircraft to meet FAR (Federal Aviation Regulation) Part 23 certification requirements for lateral stability.

The rudder-aileron interconnect provides a minimum of five degrees down aileron with full rudder deflection. Right rudder input will cause right roll input and left rudder input will cause left roll input. With neutral aileron trim, aileron inputs will not cause rudder deflection. The interconnect is a bungee cord that transmits control loads from the aileron cables to the rudder cables after a certain amount of stretch is achieved.

The SR20's operating speeds are listed in section 2 of the Pilot's Operating Handbook (POH). The full flap operating range is 56-100 KIAS, the normal operating range is 65-165 KIAS, the caution range is 165-200 KIAS and the never exceed speed (Vne) is 200 KIAS.

Weight and balance information for the accident flight was reported by CDC as having a gross weight of 2,900 lbs and a center of gravity of 31.50 inches. The corresponding center of gravity range for a weight range of 2,871-3,045 lbs was 30.19-32.81 inches. The calculations w...