History of Flight
On July 15, 2010, at 1330 central daylight time, a Zenith CH701 amateur-built aircraft, registration N701KC, collided with terrain during a landing attempt on runway 31 at Iowa Falls Municipal Airport in Iowa. The commercial-rated pilot sustained fatal injuries and the aircraft was substantially damaged. The flight was a personal local operation under Part 91 in visual meteorological conditions, originating from the same airport about 15 minutes earlier without a flight plan.
Multiple witnesses observed the accident. A flight instructor who had recently flown with the pilot reported that after a smooth engine run-up, the pilot conducted high-speed taxi runs. She then noticed the aircraft airborne about a mile southwest of the airport in a spin. The airplane descended below the tree line before climbing back up. It entered a left downwind for runway 31, and the pilot radioed his intention to land. On final approach, the aircraft appeared unstable, "washing side-to-side in slow flight," prompting the pilot to add power and execute a go-around. During a second approach, the airplane seemed stable until turning base to final. On final at approximately 200 feet above ground, it again appeared unstable in slow flight, the engine noise decreased, and the nose dropped with the right wing. The aircraft entered a spin and impacted the ground.
Pilot Information
The 74-year-old pilot held a commercial pilot certificate with single-engine land and instrument ratings. His most recent medical certificate was a second-class issued in March 1991. Logbook records indicated 755 total flight hours as of March 1984. He did not fly again until December 2009, when he began recurrent training with a flight instructor. He accumulated 5.4 hours of instruction, including a flight review in May 2010.
The instructor noted that the pilot had stopped flying years earlier and was training for sport pilot privileges. They flew a Cessna 152 and discussed differences between that aircraft and the Zenith CH701 he had built. The pilot researched the CH701's handling characteristics, particularly the "supposed inability of the elevator to work at slow airspeed without the propwash when the RPMs are pulled back." As a result, they practiced stalls and landings using elevated power settings. The Zenith factory had no record of the pilot flying a CH701 during his visit, and no evidence indicated he had ever flown this model before the accident flight.
Aircraft Information
The aircraft was an amateur-built CH701, serial number 7-6580, constructed by the pilot. It was a two-seat, fixed-gear, high-wing design intended for short takeoff and landing (STOL) operations. Features included fixed leading-edge slats, full-length flaperons, an inverted horizontal stabilizer, and an all-moving rudder (no vertical stabilizer). Power came from a Rotax 912 100-hp engine. The aircraft met the limitations for light sport aircraft operation.
The pilot purchased the kit in December 2006. A construction log showed first taxi tests on March 10, 2010. The instructor recounted that several weeks before July 4th, the pilot inadvertently became airborne during high-speed taxi tests. At about five feet above the runway, reducing power caused the nose to drop, resulting in a propeller strike, a broken nose wheel, and damage to the right wing's leading edge.
Meteorological Information
Weather conditions at the time were reported by an automated station at Waterloo Regional Airport, 45 miles east. At 1354, the wind was from 350 degrees at 6 knots, visibility 10 statute miles, clear skies, temperature 27°C, dew point 16°C, and barometric pressure 30.02 inches of mercury.
Wreckage and Impact Information
The airplane impacted a bean field in a nose-down attitude approximately 600 feet from the approach end of runway 31, coming to rest about 20 feet from the initial impact point. The left side of the fuselage, cockpit, and inboard section of the left wing sustained fire damage. Flight control continuity was established from the rudder and elevator to the cockpit; flaperon continuity was confirmed as far as possible given impact damage. All three propeller blades were fractured at the hub, with one showing chordwise scratches. Examination of the airframe revealed no failure or malfunction that would have caused the loss of control. A witness reported the engine was operating immediately before the accident.
Medical and Pathological Information
An autopsy performed on July 17, 2010, by the Iowa Office of the State Medical Examiner listed the cause of death as multiple blunt force injuries. Toxicological testing by the FAA detected 11% carbon monoxide in blood, ethanol in blood and lung (determined to be from sources other than ingestion), methanol in lung and brain, n-propanol in blood and lung, and Metoprolol in liver and blood. Metoprolol is commonly used for high blood pressure and other cardiovascular conditions.