Introduction
On April 24, 2016, about 1745 eastern daylight time, an experimental amateur-built Acroduster, registration N380JA, collided with terrain while maneuvering in the traffic pattern at Oakhill Airpark (SC82), Belton, South Carolina. The private pilot, who was also the registered owner, was fatally injured, and the airplane was destroyed. The flight was conducted under Title 14 Code of Federal Regulations Part 91 as a local personal flight. Visual meteorological conditions prevailed, and no flight plan was filed.
Witness Accounts
A pilot witness at SC82 reported that the accident pilot taxied to the approach end of runway 28, performed an engine run-up including cycling the propeller, and departed. About 30 minutes later, the witness heard the airplane return. The pilot completed two low approaches to runway 28; after the second, he made a left turn to reenter the traffic pattern. On downwind, the witness heard the propeller pitch change to a low-pitch, high-rpm sound. Another witness reported that on downwind, the engine sputtered and cut out several times, then the airplane banked left, descended, and impacted the ground nose-down.
Pilot and Aircraft Information
The pilot held a private pilot certificate with airplane single-engine land rating and a third-class medical certificate issued March 3, 2016. At that time, he reported 420 total flight hours, with 28 hours in the previous six months. He also held a repairman experimental aircraft builder certificate for the airplane, issued May 13, 2013.
The two-seat, tailwheel biplane was built by the pilot and issued an airworthiness certificate on April 21, 2013. It was powered by a Continental Motors IO-360-series 210-horsepower engine equipped with a two-blade McCauley constant-speed propeller. At the time of the accident, the airplane had about 24.7 total flight hours. Maintenance logs showed a landing incident at 22.9 hours (December 2014) requiring repairs to wings, engine, and propeller. Subsequent entries documented repairs and a condition inspection at 22.9 hours (April 10, 2016) with a note “first flight ok after rebuild.” No fueling information was found; total fuel capacity was 36 gallons.
Weather and Airport
The 1747 weather observation at Donaldson Airport (GYH), about 10 nautical miles north, reported calm wind, 10 miles visibility, clear skies below 12,000 ft, temperature 25°C, dew point 8°C, and altimeter 30.03 inHg. SC82 was a private-use airport with one turf runway (10/28), 2,400 ft long by 100 ft wide, in good condition, at elevation 837 ft msl.
Wreckage Examination
The main wreckage was in a hay field about 1,225 ft south of the runway centerpoint at 796 ft msl, on a 158° heading. A postimpact fire burned a 12 ft by 18 ft area. The left wings, fuselage, and cockpit were consumed by fire; the right wings were bent forward with inboard sections consumed. The empennage remained intact. Control continuity was confirmed from cockpit to all flight controls. The propeller remained attached; one blade bent aft 45°, the other undamaged. The spinner showed crush damage on the upward side. One propeller blade pitch change link was fractured, the other secure. The propeller control cable was attached.
Engine examination found crankshaft and valve train continuity, normal spark plug electrodes, and no cylinder anomalies via boroscope. Both magnetos were impact-separated and thermally damaged. The propeller governor was removed for further examination. The fuel pump showed thermal damage; fuel lines and injectors were intact.
Medical Information
Autopsy by the Greenville County Medical Examiner determined the pilot died from thermal injuries. Toxicological testing by the FAA detected diphenhydramine in urine and heart blood (0.024 ug/ml), a sedating antihistamine.
Engine Governor Examination
Examination of the propeller governor at the manufacturer revealed scrape marks on the pump cavity and gears, consistent with gears turning opposite normal rotation, indicating the propeller was not rotating forward at impact. No anomalies precluding normal operation were found.