On October 22, 2001, at 1609 eastern daylight time, a homebuilt Challenger II, N843C, was destroyed when it impacted terrain near Midland, Virginia. The certificated private pilot was fatally injured. Visual meteorological conditions prevailed for the local flight that departed Warrenton-Fauquier Airport (W66), Warrenton, Virginia. No flight plan was filed, and the personal flight was conducted under 14 CFR Part 91. A witness, who was flying in the traffic pattern at the time of the accident, reported that the accident airplane departed runway 14, and then turned "early" for the left crosswind leg. The accident airplane completed the traffic pattern, landed, and then departed a second time. Once again, it turned crosswind "early." The witness then lost sight of the airplane. Shortly afterwards, the witness received a radio transmission that an airplane had crashed while in the traffic pattern. He began to look for the airplane, and with in a few minutes located it. The airplane was on the ground, in a large area of trees, beneath the downwind leg, about 1/2 mile from the runway. There was an open area further along the airplane's intended track, but nothing in the immediate vicinity of the accident site. According to a Federal Aviation Administration (FAA) inspector, a witness had telephoned the airport manager and reported that the engine on the accident airplane sounded "unusual." While the witness was on the telephone, the airplane crashed. Examination of the wreckage revealed that all major components, including the flight control surfaces, were accounted for at the accident site. Flight control continuity could not be confirmed due to impact damage. The airplane was equipped with a Rotax model 503 engine with a wooden propeller. Both propeller blades had separated about 4 inches from the propeller hub. The fuel tank contained about 1/4 of a tank of fuel, and had ruptured consistent with impact damage. During the examination, no preimpact failures or malfunctions were identified. In addition, the airplane logbooks were not identified at the accident, and follow on attempts to locate them were unsuccessful. According to the pilot's wife, he had purchased the airplane, and then refurbished it. On the day of the accident, the pilot told her he was going to do some "crow hopping," (short flights with a maximum altitude of approximately 5 feet.) She added that he must have felt comfortable with the airplane, and "decided to take it to the next level." She was not aware of him doing anything except "crow hopping" prior to the accident. In addition, she was not aware of any airworthiness issues with the airplane. The pilot held a private pilot certificate with an airplane single-engine-land rating. His last FAA third-class medical certificate was dated June 6, 2001. On the pilot's medical application, he reported 85 hours of total flight experience. In addition, the pilot's logbook was not identified at the accident, and follow on attempts to locate it were unsuccessful. An autopsy was performed on the pilot at the Medical Examiners Office in Fairfax, Virginia, on October 23, 2001. The FAA Toxicology and Accident Research Laboratory in Oklahoma City, Oklahoma, performed a toxicological test on samples taken from the pilot on December 10, 2001. The operator manual for the engine stated, "Danger! This engine, by its design, is subject to sudden stoppage! Engine stoppage can result in crash landings. Such crash landings can lead to serious bodily injury or death. Never fly the aircraft equipped with this engine at locations, airspeeds, altitudes, or other circumstances from which a successful no-power landing cannot be made, after sudden engine stoppage." The manual further stated, "Warning! This is not a certificated aircraft engine. It has not received any safety or durability testing, and conforms to no aircraft standards. It is for use in experimental, uncertificated aircraft and vehicles only in which an engine failure will not compromise safety. User assumes all risk of use, and acknowledges by his use that he knows this engine is subject to sudden stoppage." According to FAA Advisory Circular AC 20-27D, Certification and Operation of Amateur-Built Aircraft, "the amateur-built program was designed to permit person(s) to build an aircraft solely for educational or recreational purposes. The FAA has always permitted amateur builders freedom to select their own designs. The FAA does not formally approve these designs since it is not practicable to develop design standards for the multitude of unique design configurations generated by kit manufacturers and amateur builders." It also stated, "Since 1983, FAA inspections of amateur-built aircraft have been limited to ensuring the use of acceptable workmanship methods, techniques, practices, and issuing operating limitations necessary to protect persons and property not involved in this activity."