On April 11, 1997, at 1935 hours mountain standard time, a Gordon Price Ultimate 10-300S, N325GP, collided inverted with runway 21L while participating in an evening air show at the MCAS, Yuma International Airport, Yuma, Arizona. The airplane was destroyed, and the pilot/owner was not injured. Visual meteorological conditions existed at the time of the flight and no flight plan was filed for the local flight that originated at 1928. The pilot reported that she has performed this particular stunt numerous times over the years both in the United States and abroad. The pilot stated that before her performance, known as the "Ring of Fire," she had personally reevaluated and chosen the location for the poles and ribbon, just to the south of the runway over old asphalt and concrete so that her flight path would parallel the runway, and also be free of any obstacles. While on her third pass through the "Ring of Fire" she was going to fly inverted, cut the ribbon, and then land. "I remember the turn-around at the west end, rolling inverted [and] establishing my sight picture for the run-in. However, the next few seconds are a total blank in my memory. I can remember the sound of the impact, but my recollection of a visual picture resumes only with the sparks created by the inverted slide." The pilot reported that there were no mechanical difficulties with the airplane. According to a sun and moon information program, official sunset had occurred at 1907, and the end of civil twilight was 1932. The "Ring of Fire" routine did not start until 1935. An Federal Aviation Administration (FAA) inspector from the Scottsdale, Arizona, Flight Standard District Office reported that there are no altitude restrictions for a routine that includes only straight and level flight. Aerobatics can be performed after legal sunset at an altitude of 500 feet above ground level (agl) or higher. The FAA inspector reported that the "Ring of Fire" routine required the pilot to fly directly into a setting sun and then turn around for the inverted pass. The pilot would then have to fly inverted into a "black hole," in order to complete the routine. The FAA inspector reported that no mechanical deficiencies were discovered during an examination of the aircraft.