The pilot was having difficulty controlling the airplane’s rudder pedals due to his physical stature. After several taxi attempts up and down the runway, he elected to take off for a short flight. After becoming airborne, the pilot began to have yaw controllability problems. He attempted to land, but was unable to control the airplane’s movements effectively, as his knees were contacting the instrument panel, and his feet were wedged behind the rudder pedals. The airplane continued to fly over terrain about 6 feet above ground level. With trees approaching, the pilot pushed the nose of the airplane down resulting in a hard landing. The airplane sustained substantial damage to the forward portion of the fuselage and the left wing. The pilot reported that there were no preaccident mechanical failures or malfunctions with the airplane that would have precluded normal operation.