On October 31, 2002, at 1550 eastern standard time, an Aeronca 7AC, N83651, registered to and operated by the commercial pilot, taxied unmanned and collided with a hangar and a parked airplane at Warner Robins Air Park in Warner Robins, Georgia. The personal flight was operated under the provisions of Title 14 CFR Part 91 with no flight plan filed. Visual meteorological conditions prevailed. The commercial pilot received minor injuries, and the airplane and a parked airplane sustained substantial damage. The local flight was originating from Warner Robins, Georgia, at the time of the accident. The pilot pulled the airplane out of the hangar, chocked a main wheel, and completed the preflight procedures with the intention of performing a currency flight in the pattern. Normal starting procedure for the airplane included turning the propeller by hand, because it was not equipped with an electric starter. The pilot performed the starting procedure three times without success. The pilot stated he next used the primer valve to prime the engine twice, then repeated the starting procedure, but the engine did not start. He stated he used the primer one more time, repeated the starting procedure with the throttle "cracked," and the engine started and spun up to high rpm. The pilot stated he "hurried to get inside to retard the throttle and/or switch off the mags," but the airplane lurched forward over the chock. The pilot was able to grab the rear control stick and was dragged by the airplane as it taxied off. The pilot stated he "felt the airplane wanting to fly," but he was able to push the control stick forward enough to keep the airplane on the ground. The airplane dragged the pilot around two or three circles, then the pilot let go of the control stick, fell to the ground, and the airplane's tailwheel ran over his right ankle. The airplane continued in a counter-clockwise ground loop, and the pilot again attempted to gain access to the cockpit, was struck in the head by the right wing strut, and fell to the ground. The pilot again attempted to gain control of the airplane, but it collided with a hangar and a parked airplane before coming to a stop. Examination of the airplane revealed damage to the propeller and wing spar, and the parked airplane sustained wing spar damage. Examination of the cement pad where the wheel chock was found revealed a fresh fuel stain approximately eight feet long and four feet wide with several boot/shoe tracks through it. A review of Federal Aviation Administration Advisory Circular AC165-12A, Chapter 10, Engine Maintenance and Operation, Reciprocating Engine Operation, Table 10, Troubleshooting Opposed Engines, revealed the corrective action for an engine that fails to start due to overpriming is, "Open throttle and 'unload' engine by rotating the propeller." The pilot reported no mechanical malfunction with the airplane.