On May 11, 1998, at 2020 eastern daylight time (edt), a Dangremond Challenger II, N199DD, operated by a private pilot, was destroyed when on climbout after takeoff, the airplane's right wing strut failed. The airplane subsequently departed controlled flight and impacted the terrain. Visual meteorological conditions prevailed at the time of the accident. The personal flight was being conducted under 14 CFR Part 91. No flight plan was on file. The pilot reported no injuries. The local flight originated at Wayland, Michigan. In his written statement, the pilot said that this was the airplane's first flight. During the initial climb, the right wing strut separated from the fuselage. The pilot said that the airplane was approximately 300 feet above ground level when it entered a right spin. The airplane impacted the ground in an upright position. The pilot said that the right strut bolt was improperly installed. A Federal Aviation Administration (FAA) inspector examined the airplane at the accident site. The airplane's fuselage, beneath and forward of the cabin area, was crushed aft and upward. The right main landing gear was broken inward. The left main landing gear was bent upward and broken off at the gear leg's mid-point. The right wing was bent downward at the forward spar. The upper wing skin fabric showed wrinkles fanning aft and outward from the bend. The top of the right wing showed skin wrinkles. The right side of the fuselage, aft of the cabin area to the boom, showed skin wrinkles. The top of the tail boom at the propeller arc was torn open. The airplane's pusher engine was bent over to the right at the firewall. Two of the three propeller blades were broken aft at mid-span. Flight control continuity was confirmed. Examination of the right wing forward strut showed that the attachment bolt was installed through the fiberglass faring surrounding the strut, but not through the strut itself. Examination of the engine, engine controls, and other airplane systems showed no anomalies.