The pilot stated that he was conducting a visual approach for a full-stop landing with a gusting wind. The airplane experienced a sudden loss of altitude while on final approach and the pilot realized that he would land short of the runway. The airplane impacted terrain approximately 1,000 feet short of the runway threshold, resulting in substantial damage to the forward fuselage and engine firewall. The pilot sustained a concussion during the impact and was unable to recall the events of the accident subsequent to the loss of altitude. A pilot-rated witness saw the airplane on a one-quarter mile final approach, and observed it bank to the right between 45-60 degrees, then bank to the left about 20 degrees, with an approximate 30-degree nose-high attitude. The airplane appeared to stall and then disappeared from his view. Both the pilot and a Federal Aviation Administration inspector who responded to the accident stated that there were no preexisting mechanical malfunctions or anomalies with the airplane.