Schweizer 269C crash near Piney Flats, TN, United States

HISTORY OF FLIGHTOn May 24, 2012, at approximately 1830 eastern daylight time, a Schweizer 269C, N760DA, was substantially damaged during a hard landing, after a loss of tail rotor effectiveness, in Piney Flats, Tennessee. The certificated commercial pilot and his pilot rated passenger were not injured. Visual meteorological conditions prevailed, and no flight plan was filed for the local personal flight operated under Title 14 Code of Federal Regulations (CFR) Part 91. According to the pilot, the flight originated at his farm in Piney Flats, Tennessee. After the departure on the local sightseeing flight with his friend they did a visual approach and landing, at Elizabethton Municipal Airport (0A9), Elizabethton, Tennessee, then took off and returned to his farm for landing. While on a short final approach for landing he heard a "high pitched whine", and the tail rotor authority degraded. He immediately initiated a full auto-rotation to landing. During the landing the helicopter touched down in a field approximately 100 yards from the pilot's hangar. Examination of the field revealed that it was grass covered, and that the point where the helicopter touched down was uneven and sloped away from the hangar and the helicopters direction of flight. The struts and main landing gear collapsed, and the tailskid assembly and vertical tail struck the ground. Prior to the event, the pilot did not see any warning lights or note any abnormalities. PERSONNEL INFORMATIONAccording to Federal Aviation Administration (FAA) and pilot records, the pilot held a commercial pilot certificate with ratings for rotorcraft-helicopter, Private privileges for airplane single-engine land, and instrument airplane. He also held a flight instructor certificate with a rating for rotorcraft-helicopter. His most recent FAA third-class medical certificate was issued on June 4, 2010. He reported 967 hours of total flight experience, 586 of which was in the accident helicopter make and model. According to FAA records, the pilot rated passenger held a commercial pilot certificate with ratings for airplane single-engine land, airplane multi-engine land, and instrument airplane. His most recent FAA second-class medical certificate was issued on October 1, 2008. AIRCRAFT INFORMATION The accident aircraft was a single-engine, three seat, light utility helicopter, powered by a 190 horsepower, air cooled, Lycoming HIO-360-D1A engine, constructed primarily of aluminum alloy. It was equipped with conventional collective and cyclic control sticks and tail rotor control pedals. The main rotor was a fully articulated three- bladed, design and the tail rotor was a two bladed, semi-rigid, anti-torque rotor design. Power was transmitted from the engine to the rotor system through a V-belt drive which incorporated a free-wheeling (one-way) sprag clutch, a main drive transmission, a tail rotor transmission, and shafts. The center section frame was constructed primarily of tubular steel. It supported the cabin and all major structural and drive train components of the helicopter. The landing gear assembly which was a skid type was also attached to the center section frame and utilized air-oil dampers, between the struts and cross beams to cushion landings. The tailboom was composed of an aluminum alloy tube containing a center bulkhead and forward attachment fitting also of an aluminum alloy. The tailboom also served as a support structure to which the horizontal stabilizer, the vertical stabilizer, the tail rotor transmission driveshaft, and the control rod for tail rotor blade pitch control were attached to. According to FAA and maintenance records, the helicopter was manufactured in 1988. It was maintained by a certificated airframe and powerplant mechanic under the provisions of Title 14 CFR Part 43. At the time of the accident, the helicopter had accrued 6523.4 total hours of operation. The last recorded maintenance on the helicopter was cleaning and repacking of the lower pulley bearings at 6,494.5 total hours of operation. This was completed on December 29, 2011. The helicopter's most recent annual inspection was completed on December 9, 2011, at 6488.6 total hours of operation. The previous annual and 1200 hour inspection was completed on November 5, 2010 at 6,417.2 total hours of operation. METEOROLOGICAL INFORMATIONThe recorded weather at Tri-Cities Regional Airport (TRI), Bristol, Tennessee, located 6 nautical miles northwest of the accident site, at 1853, approximately 23 minutes after the accident, included: calm winds, 10 miles visibility, few clouds at 6,500 feet, scattered clouds at 10,000 feet, temperature 27 degrees C, dew point 13 degrees C, and an altimeter setting of 29.96 inches of mercury. WRECKAGE AND IMPACT INFORMATIONExamination of the wreckage revealed that the helicopter was substantially damaged. Fuel System Examination of the fuel tanks revealed that they had not been compromised and that they were approximately half full and the right fuel tank was displaced outboard in its retention straps. Cabin The cabin was intact; however the aft cabin wall upper beam was distorted on both sides of the mast. The seat deck was straight with no apparent distortion on either side. The instrument panel had remained attached to the floor but, was tilted to the left. The instruments and glass that covered the instrument faces was undamaged. Main Frame The main frame was intact with no breaks but exhibited kinking and bending to several of the tubes which made up the frame's structure. The mast support struts were intact and attached but, the cabin floor support struts exhibited damage, the left side was bowed and the right side was kinked. The aft cross beam center area exhibited upward bending and the ends were bent forward. The forward cross beam appeared intact and straight. The diagonal drag struts were damaged with the left side bowed, and the right side separated from the forward rod end bearing. The right aft landing gear damper had remained attached but was bent, and the remainder of the dampers, were separated at one or both ends. The right skid was separated at the forward side of the strut leg. Tail Boom The tail boom was intact and attached. The tail boom support strut tubes were intact and were attached at upper and lower fittings. The tailboom center attach fitting was intact. The forward tail boom bulkhead fitting was also intact. The horizontal stabilizer appeared undamaged but, the vertical stabilizer exhibited compression bending and was folded to the right. Flight Control System Examination of the flight control system revealed no evidence of any preaccident anomalies or failures. Control continuity existed from the cyclic pitch control and the collective pitch control to the swash plate assembly and main rotor pitch links and from the tail rotor pedals to the tail rotor blade pitch links. Main and Tail Rotors All three main rotor blades were still attached to the rotor head, and the main rotor hub, pitch housings, rotor blades, and dampers were still attached and were undamaged. The main rotor head was also intact and had remained attached to the main driveshaft, mast and transmission. The tail rotor assembly was intact, attached, and was also undamaged. The tail rotor hub and fork were also intact and had remained attached to the tail gear box shaft. Transmissions and Driveshafts The transmissions and drive shafts were intact and attached. Drive system rotation was confirmed at the lower pulley shaft, and the sprag (overrunning) clutch operated correctly. The lower pulley drive shaft was engaged and found intact with no apparent damage. The forward and aft tail rotor drive shaft spline couplings were also intact and lubricated. Examination of the drive train revealed however, that the tail rotor driveshaft (TRDS) had become uncoupled from the drive assembly and main rotor belt transmission, and the TRDS could be rotated freely by hand in both