At about 1525 Eastern time, the airplane experienced an in-flight loss of control and crashed during takeoff. Visual conditions prevailed. The airplane was substantially damaged; the Commercial pilot and sole occupant was fatally injured. A witness reported the airplane becoming airborne and yawing to the left. The airplane climbed out slowly to no greater than 50-60 feet agl with its landing gear extended. At that point, the “…left wing dropped and it went straight down.” The witness further stated he did not hear any loud engine noises or power changes. Another witness reported hearing what he thought was a failure of the left engine at the moment the airplane departed the runway. The airplane was in a steep climb, rolled to the left and pitched straight down.