On June 12, 2020, at 1950 eastern daylight time, an experimental amateur-built Vans RV8 airplane, N553KM, was substantially damaged when it was involved in an accident at Henry County Airport (HMP), Hampton, Georgia. The pilot was seriously injured. The flight was conducted under the provisions of Title 14 Code of Federal Regulations Part 91. A witness captured the accident flight on video. The airplane is seen taking off, entering a steep climb, performing a tight 180° turn, and then descending steeply before leveling off near the ground and traveling in the opposite direction of takeoff over the airfield as the video ends. The engine can be heard misfiring throughout the video and black smoke can be seen trailing the airplane. Witness testimony of what was seen and heard was consistent with the video. Witnesses further described the airplane entering a subsequent 180°-turn for landing on the departure runway. At low altitude, and low airspeed, the airplane "stalled." The airplane subsequently aligned with the left base leg of the traffic pattern for runway 06 at a low altitude and then impacted terrain in a flat attitude at the approach end of the runway. The landing gear and cockpit canopy separated, and the wings and the fuselage were substantially damaged. Examination of video footage of the accident flight forwarded by the airplane’s owner revealed a steep, nearly vertical climb after takeoff, followed by maneuvers consistent with those described by the witnesses. Data recovered from non-volatile memory of onboard avionics suggested a steep pitch upward followed by a steep left roll after takeoff. The maneuvers were depicted below 500 ft, over the runway environment, with large pitch and roll values, followed by a loss of oil pressure and RPM. A postaccident examination of the airplane was conducted and flight control continuity was confirmed. The engine was examined, and the No. 2 fuel nozzle was found blocked by an unspecified material. Examination of the spark plugs (top and bottom) revealed signatures consistent with "rich" mixtures in the Nos. 1 and 4 cylinders, and "lean" mixtures in the Nos. 2 and 3 cylinders. No other anomalies were noted with the airframe or engine.