At about 1758 Central time, the airplane sustained substantial damage on impacting terrain during takeoff. The Private pilot sustained fatal injuries. A witness later stated that, about halfway down the runway, the airplane emitted a sound like a rapid misfire, a pop, and then no more audible engine sounds. The airplane was about 300 to 400 feet agl at that point. He said that the airplane turned right then turned left to a bank where the wing was straight down. The airplanes wings then leveled, the airplane descended, and it impacted terrain. He stated that the time from the sounds to the impact was about two to three seconds. To date, the investigation has not discovered a reason for the apparent engine failure.