Primary finding
Probable cause
the pilot's failure to shut down the engine prior to exiting the helicopter resulting in the tail rotor contacting the ground. A contributing factor was the gusting wind conditions present at the accident site.
Investigator assessment
Analysis narrative
The pilot landed in a flat grass covered field for the purpose of removing a long line and bambi bucket used in firefighting operations. Following touchdown, the pilot rolled the throttle to flight idle, and applied the frictions for the cyclic and collective. The wind conditions at the time were from 060 degrees at 19 knots gusting to 25 knots. After the pilot exited the helicopter, a gust of wind caught the unattended rotor disk, and tilted it, causing the helicopter to tilt rearward on its skids. The pilot returned to the controls just as the tail rotor made contact with the ground. He leveled the helicopter, brought the engine back to flight idle, and initiated a hover. The pilot stated that after he performed several pedal turns and noticed no control hindrance, he elected to return to Kahului. The helicopter sustained substantial damage consisting of damaged tail rotor blades and a bent and twisted tail rotor system drive shaft.
Source record
Factual narrative
On August 12, 2006, about 1645 Hawaiian standard time, a Hughes 369D, N114HD, contacted the ground with its tail rotor near Lahaina, Hawaii. Windwood Aviation, Inc., operated the helicopter under the provisions of 14 CFR Part 91. The commercial pilot, the sole occupant, was not injured; the helicopter sustained substantial damage consisting of damaged tail rotor blades and a bent and twisted tail rotor system drive shaft. The local flight departed Kahului, Hawaii (OGG), about 1600 on a firefighting mission. Visual meteorological conditions prevailed, and a company visual flight rules (VFR) flight plan had been filed. The pilot stated in a written report that he landed at a grass flat near a reservoir on the eastern side of a valley, which was prone to gusty winds. He rolled the throttle to flight idle, and applied the frictions for the cyclic and collective. He exited the helicopter, and proceeded to detach the electrical connection and hook ring of a bambi bucket used for firefighting. A gust of wind tilted the helicopter rearward on its skids. The pilot returned to the controls as the tail rotor made contact with the ground. He leveled the helicopter, accelerated to flight idle, and initiated a hover to prevent further damage. He performed several pedal turns, and collective changes. The flight characteristics seemed normal, and he noticed no control hindrance. He returned to Kahului. The pilot stated that since the event occurred while he was not flying, he did not recognize its significance. He received radio instructions to proceed to another emergency. He said that in his haste and determination to stay on his mission, he did not adhere to safety protocols. The winds at Kahului Airport, 12 miles southeast of the accident site, were reported to be 060 degrees at 19 knots gusting to 25 knots.