20140925019389A

The aircraft was conducting a phase 1 flight for experimental amateur built operating limitations out of the Sedona Airport area. The pilot stated the aircraft had handled normally during taxi and take off roll. As part of this phase 1 flight regime the pilot conducted aerobatic maneuvers to include a 4-point roll. He described this as a maneuver which requires rapid stop-to-stop rudder input.

The pilot stated that he initiated a slip on final approach which was the normal procedure for landing this aircraft. All was proceeding normally as the aircraft touched down on the main gear. When the tail wheel lowered and touched down the aircraft made a violent 90 degree turn/yaw to the right. The pilot attempted to apply left rudder and brake, but the aircraft departed the runway to the right and dug into soft dirt off the side of the runway. The right gear dug into the dirt and the aircraft cartwheeled. The pilot attempted to stop the roll by applying left aileron and the aircraft rolled level. The aircraft then traveled down a 5 foot embankment and came to a stop after the prop & engine struck the ground.

The pilot shut all power and fuel off to the aircraft and exited the aircraft.

The aircraft sustained damage to the right upper and lower wing tip, the upper right hand wing spar was cracked, the left lower wing tip and lower aileron were damaged, left hand landing gear bent, damage to the fairings & wheelpants, damage to the fuselage frame in the landing gear attach area, and potential damage to the fuel tank area. The prop was destroyed and the engine encountered sudden stoppage as well.

The pilot walked away from the aircraft with no injuries. He stated that he was wearing the 5 point seatbelt and helmet which he always wears. He said he could remember ratcheting the seatbelt tight prior to landing.

The pilot is an experienced pilot with a background in competition aerobatic flying. This aircraft was his third pitts which he had built and flown from the first flight. He explained that prior to this flight this aircraft had appeared normal during preflight and had handled normally throughout the in-flight portion of operation. He states this aircraft was the best handling pitts aircraft he had built and flown.

This landing was approximately the 90th on this aircraft tailwheel assembly.

The tailwheel was observed to be cocked 90 degrees to the right at the accident scene. When the aircraft was moved it was noted the tailwheel assembly did not return to center and appeared to be frozen in the cocked position. The rudder to tailwheel attach cable/chain was also broken. It is unclear whether the cable/chain broke as a result of the accident or was broken prior to landing.

The pilot/builder asked a local mechanic/ia to assist by inspecting & disassembling the tailwheel assembly. It took considerable effort to disassemble the tailwheel unit as there was something jammed in the assembly. It was determined that the wheel centering spring had jammed between the wheel fork post and the housing assy. Causing the whole unit to jamb in position.

The pilot believes that the tailwheel jammed into position 90 degree to centerline during the aerobatic maneuvers he had conducted during the flight.