20120818021349A

On August 18, 2012 at approximate 0639 hours PDT, Boeing model B75N1 (stearman) N47964 ground looped after landing and came to rest in the center infield of the Falcon field airport (ffz), Mesa, AZ.no injuries were sustained. The pilot reports he took off from Falcon field (kffz) at around 0630 for his normal early Saturday morning flight to practice landings in stearman 47964, N2S (PT-17).the pilot states he has for the previous month or so has flown almost every Saturday morning to practice landings just to stay proficient in the aircraft. Start-up and taxi were uneventful. The active runway at the time was 22L & 22R with ATIS information alpha as the current information. He believes the winds were reported as 160 @ 8.the commemorative air force hangar/ramp is located at the approach end of 4R which required the airman to taxi to the other end or east side of the airport to 22L.during taxi he did not notice any issues with the aircraft. Run-up was uneventful and engine power, magneto and carburetor heat checks were within limits. The pilot was cleared for take-off and cleared to enter a right traffic pattern for 22R. The pilot preceded to lineup on runway 22R and take-off. The take-off was normal. Downwind was normal, (80 mph and 1,850 RPM) and abeam the approach end of 22R he applied carburetor heat, reduced throttle to 1,300 RPM, adjusted trim and established a normal 80 mph descent. He states he maintained this configuration until turning final at which time he removed carburetor heat (momentarily advancing the throttle to ensure he had engine response) and continued the approach until "over the fence" at which time he closed the throttle and began the flare to a three (3) point landing. As he lined up on finalhe states he was able to maintain alignment with the runway center line without significant cross controlling or crabbing. The landing approach was stable throughout the full approach to landing. The pilot on touch down the runway centerline was between the landing gear at which time he ensured he had the stick all the way back to maintain tail wheel contact with the runway. The wings were level and he was maintaining slight left stick and controlling direction with the rudder when the tail of the aircraft rather abruptly kicked out to the right. He reacted with right rudder but was unable to completely correct the rotation and departing the left side of runway (22R) about 25% of the way down the runway as he recalls. The pilot states the heels of his feet were on the deck to ensure he did not inadvertently hit the brakes and he continued to stay off the brakes to prevent a prop strike by flipping the aircraft tail over nose. He believes he reacted immediately to the tail movement but, obviously didn't salvage the landing without a ground-loop. As the ground loop occurred the aircraft was in the water retention basin between runways 22R and 22L. The aircraft was in a position during the final stages of the ground loop that the right lower wing struck the upslope of the southern rim of the retention basin just prior to the aircraft stopping. Inspection of the aircraft exhibited damage to the right outboard lower wingtip area and aft spar. This damage consisted of damage to the wing tip cloth and wood damage, first rib inboard of the wing tip cloth and wood damage. Right lower aileron is bent and has wood and fabric damage. Upon further inspection of the wing it was discovered the lower wing aft spar at the wing strut attaches point had several cracks protruding from bolt holes of the attaching strut to spar attach plate. No additional damage was noticed. The aircraft did not sustain engine stoppage or a propeller strike.