On June 18, 2004, approximately 1000 mountain daylight time, an unregistered non-certified Quick Silver MXL aircraft impacted the terrain about seven miles east of Mountain Home, Idaho. The individual flying the aircraft, who's student pilot certificate expired in January of 1999, received fatal injuries, and the aircraft, which was owned and operated by the pilot, sustained substantial damage. There were no other occupants. The 14 CFR Part 91 personal pleasure flight, departed the Oasis Truck Stop, which is located about 15 miles southeast of Boise, Idaho, about 0930. The aircraft, which was being operated in visual meteorological conditions, was en route to Fairfield, Idaho. No flight plan had been filed. According to witnesses, the pilot landed at the Oasis Truck Stop to take on automobile fuel for the operation of his aircraft. Records show that he refueled at 0910, and witnesses said that he took off from a road beside the truck stop about 0930. After takeoff, the pilot flew past a private airstrip about a mile from the truck stop, and then headed in the direction of Fairfield, where a gathering of ultralight-type aircraft was taking place. About 30 minutes later an individual on the ground came upon the wreckage of the aircraft near some hilly terrain. There were no witnesses to the impact, and there was no fire. The entire aircraft structure was located together, and there were no ground scars indicating any movement across the terrain after the initial impact. According to the FAA Inspector who examined the aircraft structure, there was no indication of an in-flight structural failure, nor any evidence of an engine malfunction. He did discover however that the wing washout angle had been changed by the pilot so that the aircraft would cruise at a faster speed. A discussion with owners of similar aircraft, who knew this pilot and his aircraft well, determined that since the pilot had made the washout angle change, and added a large windshield to the airframe, the aircraft's cruise speed was only about 10 knots greater than its stall speed. Witnesses also reported that there were very strong gusty winds (to 20 knots) and moderate turbulence in the area at the time of the accident. It was the opinion of the FAA Inspector who responded to the scene that the pilot had lost control of the aircraft while attempting to continue his flight in the windy/gusty conditions.