On March 25, 2001, at 1135 central standard time, a Cartercopters Cartercopter experimental prototype gyroplane, N121CC, registered to and operated by Cartercopters LLC of Wichita Falls, Texas, was substantially damaged when the main rotor contacted the tail during landing following an aborted takeoff at the Olney Municipal Airport near Olney, Texas. The commercial pilot and crewmember were not injured. Visual meteorological conditions prevailed, and a flight plan was not filed for the 14 Code of Federal Regulations Part 91 test flight. The local flight was originating at the time of the accident. The pilot reported to the NTSB that a design change was made to the main rotor pitch system prior to the accident flight. The change incorporated an increase to the main rotor pitch with the collective in the down position. The flight was to takeoff from runway 4, climb to 50 feet, fly along the runway, and land on the departure end of the runway. After lift off from the runway, about 5 feet, "a severe out of track condition was noted and the fuselage rolled left. I immediately reduced throttle to abort [the] takeoff and attempted to level the aircraft." In order to level the aircraft prior to touchdown, the pilot had to increase the collective to 7 degrees in order to keep the aircraft airborne until the roll could be corrected. "The airspeed had increased to 60 mph, which was too high [an] airspeed for the collective position and rotor rpm. Rotor exceeded flapping limits and struck [the] tail and pusher prop on landing." The pilot stated that the accident could have been prevented by "improved and more visible rotor rpm and blade flapping indication."