Naples Municipal Airport
Aircraft Accident/Incident Report

Naples, Florida 34104
Monday, February 3, 2014 13:50 EST

On February 3, 2014, about 1350 eastern standard time, a Hughes 369D, N8618F, operated by the Collier Mosquito Control District, was substantially damaged during a practice 180 degree autorotation to touchdown at Naples Municipal Airport (APF), Naples, Florida. The airline transport pilot and flight instructor were not injured. Visual meteorological conditions prevailed, and no flight plan was filed for the local public use training flight. According to the flight instructor, prior to the last practice "fulldown" autorotation, they had performed two running landings, two stuck left pedal maneuvers, three stuck right pedal maneuvers, and eight successful autorotations. Just like the previous eight, the helicopter responded the same during the flare but this time it suddenly lost altitude and contacted the ground. The instructor "quickly grabbed" the controls and landed the helicopter which had yawed 90 degrees to the right. The airline transport pilot then asked him what happened. According to the airplane transport pilot (ATP), he was undergoing annual proficiency training, and after completing the simulated stuck pedal maneuvers, and run on landings, four straight in touchdown autorotations were performed, followed by 180 degree autorotations to touchdown. Two were performed successfully but, on the third one, the tail of the helicopter contacted the ground. The ATP believed that the entry to the maneuver was normal and that during the turn to achieve the rollout prior to touchdown that the helicopter was level and was "essentially" into the wind, at most 10 to 15 degrees left of the nose and landing direction. He was at the target speed of approximately 60 knots indicated airspeed, and the rotor rpm was in the "mid-green arc." The flare was initiated about 50 feet above ground level (agl) to arrest the forward motion as he had done on the previous autorotations but, at some point during the flare he felt a "bump." The procedure was continued per the profile with the forward motion having been arrested, the helicopter was leveled off and a "pitch pull" was initiated, resulting in a "normal" touchdown with little forward motion, coming to rest turned to the right from its flight path by approximately 60 degrees. According to a witness, who was watching the helicopter doing autorotations, he "took interest" in this particular approach as the helicopter seemed to be "falling a little more rapidly and aggressively" then before. At approximately 100 feet agl, he then observed the helicopter "nose up aggressively," the tail strike the ground, dirt being thrown upwards on to the top of the helicopter, and then it coming to rest with the main rotor still turning. A cursory examination of the helicopter revealed that the tail rotor blades exhibited impact damage and were twisted and bent. The tail rotor driveshaft was also twisted and bent, the horizontal stabilizer was bent, the forward and aft tail rotor drive shaft couplings were damaged, the tail rotor driveshaft dampener was distorted, and the tail rotor output shaft on the transmission was bent.

Not Yet Reported