On June 19, 1997, about 1040 central daylight time, a homebuilt Pitts S1S, N7211R, registered to a private owner, operating as a 14 CFR Part 91 personal flight, experienced an on-ground loss of directional control on landing rollout at Greenwood Leflore Airport, Greenwood, Mississippi, and nosed over. Visual meteorological conditions prevailed and no flight plan was filed. The airplane sustained substantial damage. The airline transport-rated pilot reported no injuries. The flight originated from a private airfield in Grenada, Mississippi, about 6 minutes before the accident. The pilot stated he made a three-point landing. On landing rollout at about 50-60 mph he experienced a total loss of directional control. The airplane veered to the right, he applied full left rudder and brake, the left wing tip collided with the ground and the airplane nosed over inverted. The pilot indicated he had between 5 to 10 hours in the Pitts S1S aircraft. An FAA inspector who went to the crash site on June 19, 1997, stated he found several broken steel hose clamps that might be of a safety hazard to for landing aircraft. In addition, he noticed a grove in the middle of the runway that may be wide enough to cause control problems for a small tail wheel aircraft. An FAA Airports Safety Inspector examined the runway on June 25, 1997. The inspector walked the full length of the runway along the centerline. The depth of the crack was minimal. The crack depth was about the thickness of a half dollar in most places. The crack went straight down the middle of the runway, which was associated with a butt joint from the original overlay. On June 27, 1997, another FAA Principal Operations Inspector examined the runway to determine if the runway may have been a factor in the aircraft accident. The inspector walked the entire length of the runway observing its condition. "The runway had an uneven joint extending the length of the runway along the approximate center of the runway. The joint/groove was probably caused during an overlay of pavement on an existing runway. The joint has grass growing up through the entire length which nearly fills the joint in some areas. The groove in some areas is approximately 3/8 to 1/2 inch deep and 1-1/2 to 2 inches wide. The sides of the groove do not have sharp/square edges in most areas, but are worn, rounded and jagged. In my opinion, the joint/grove probably did not cause a loss of directional control of the aircraft on landing or during the subsequent roll out. The loss of directional control was probably pilot or aircraft induced." The Greenwood-Leflore Airport Manager verified an FAA inspector from the FAA Airports District Office conducted an inspection of runway 27 on June 25, 1997. The Airport Manager stated the inspector stated, "in his opinion that the cracks in the runway were not large enough to cause an accident. The aircraft owner brought the tail wheel of the airplane to the airport and he and the airport manager reexamined the runway where the accident occurred. The airport manager stated, "The cracks are approximately 1 inch wide by about 1/4 inch in depth. We were able to carefully balance the tail wheel in a crack. In my opinion the shape of this particular tail wheel made it possible to balance it in almost any size crack. The shape of the tail wheel should cause it to come out of the crack smoothly. I am enclosing a drawing showing runway 27 in the area where the accident occurred, this drawing shows the distances involved in the accident. The left brake on the airplane was applied, skid marks show a right turn to about 48 feet. The tire shows uneven markings, and also that it was bouncing. Just past this point the wheel took to the inside enough that the outside of the wheel pants rubbed the runway. At 35 feet further the left wing tip struck the runway, after another 8 feet the prop struck the runway, 7 feet later, the spinner scrapped the runway and the aircraft flipped over on its back stopping about 22 feet from the edge of the runway." The owner stated, "as you can see, the cracks in the surface of the runway are wide enough to accommodate the tail wheel of my aircraft. If the tail wheel swivels over approximately 20 degrees in either side of centerline, then the wheel becomes free to turn in any direction. It is my contention that either the FOD (hoses and clamps) or the irregularities (cracks) in the runway caused my tail wheel to become free wheeling and caused the loss of directional control after landing." Examination of the airframe, flight controls, and brake assembly revealed no evidence of a precrash mechanical failure or malfunction.