On October 7, 2003, about 1610 eastern daylight time, a homebuilt Edge-540, N540SH, was destroyed when it impacted terrain while maneuvering in Warrenton, Virginia. The certificated commercial pilot was fatally injured. Visual meteorological conditions prevailed and no flight plan was filed for the personal flight conducted under 14 CFR Part 91. The pilot was practicing aerobatics above the Warrenton-Fauquier Airport, for an upcoming air show. A witness stated he observed the airplane performing a "spin maneuver." He further stated, "...The aircraft seemed to take an extensive amount of time starting a recovery. [It] began recovering from the dive then disappeared behind the hangars. I then heard the aircraft impact...." Another witness stated he observed the airplane flying straight and level about 40 feet above a runway. The airplane then pitched up and began to climb vertically to an estimated altitude of about 600 feet. The airplane then pitched down 180 degrees, and began to "corkscrew" downward, before it leveled off and entered a flat spin. When the airplane was about 40 feet above the ground, the airplane's rotation slowed to a near stop, and it's nose dropped about 20 to 30 degrees. The airplane then began a "sluggish" movement downward and forward, until it impacted the ground. The witness added that he could hear the engine running until the airplane impacted the ground. Examination of the airplane by a Federal Aviation Administration (FAA) inspector did not reveal any pre-impact mechanical malfunctions. Review of maintenance records revealed that the airplane had been operated for about 520 hours at the time of it's most recent condition inspection, which was performed on September 13, 2003. The airplane had been operated for about 23 hours since the inspection. The pilot purchased the airplane on January 27, 2003. He reported 4,100 hours of total flight experience on his most recent application for an FAA second class medical certificate, which was dated April 30, 2002. He also possessed a statement of acrobatic competency which was valid until August 31, 2004.