At about 1852 Eastern time, the airplane collided with terrain and was substantially damaged. The sport pilot sustained serious injuries. Visual conditions prevailed. According to a witness, the airplane climbed to approximately 500 feet after takeoff. As the airplane was turning to the left, its nose “dived,” and the airplane descended rapidly. As the airplane descended the pilot pulled up at the last few seconds, clipped a tree, and landed very hard in a field. The airplane continued through a fence and across a dirt road, where it nosed over and came to rest inverted. Examination of the aircraft and engine revealed no evidence of pre-impact mechanical malfunction.