On June 22, 2000, at 1950 central daylight time, an Aeronca 11AC, N85861, ground looped during landing on runway 18 at the Pittman Memorial Airport in Tylertown, Mississippi. The airplane was operated by the pilot under the provisions of Title 14 CFR Part 91 and visual flight rules. Visual meteorological conditions prevailed and no flight plan was filed for the local instructional flight. The private pilot and certified flight instructor (CFI) were not injured and the airplane received substantial damage. The flight had originated from McComb-Pike County-Lewis Airport, in McComb, Mississippi, at 1910. According to the CFI who was occupying the right seat, they had been practicing both three-point and wheel landings. He said that this particular landing was a three-point landing. He said that when they touched down, the tail-wheel shook excessively back and forth at first and then it was smooth. He stated that the airplane veered right while both of them were pushing on the left rudder. The airplane departed the right side of the runway turned around about 180 degrees, slid left into a ditch and collapsed the left main landing gear. According to the CFI, and FAA Inspector, a tail-wheel spring and associated parts had pulled apart from the tail-wheel and were later found on the runway near the point where the airplane veered off the runway.