CHI04LA265 · Kenny Mariner-MF Boat

The experimental amateur-built airplane was substantially damaged and the pilot seriously injured when the left wing tip struck the ground during landing causing the aircraft to spin around and crash. The pilot stated that this was the first flight of the airplane since it had been rebuilt. He reported that ground taxi testing was conducted and did not reveal any problems. According to the pilot, after takeoff the airplane was "swaying side to side." He decided to return for landing and entered a left-hand traffic pattern. The pilot reportedly reduced engine power on base leg and began a descent for landing. He stated that the nose was "pitching and yaw[ing] back and forth." The wings did not want to stay level, according to the pilot. He noted the final approach was into the wind with some "side gust." On final approach, about 8 feet above the ground, wind conditions caused the left wing to hit the ground and the airplane spun around. The airplane came to rest about 100 feet southeast of the runway. The airport manager witnessed the accident. He reported that during takeoff the airplane porpoised twice before it started climbing. He noticed the airplane again on what appeared to be a downwind traffic pattern leg for runway 13. He noted that "the aircraft looked like it was having control problems and could not stay in coordinated flight. It looked like every time he attempted to make a left turn the airplane would skid to the right." The witness reported that during the landing the aircraft was "very uncoordinated" and started to porpoise 4 or 5 times above the runway. The witness stated the engine power accelerated and then the left wing tip struck the ground and the aircraft crashed. A post-accident examination of the wreckage revealed no defects associated with a pre-impact failure. Flight control continuity was confirmed.

Verbatim NTSB analysis and probable cause from the NTSB dataset