ATL07GA087

The pilot reported that while flying low over trees in a left turn, a strong gust of wind was encountered causing the helicopter to yaw to the right. The pilot reduced the collective in an attempt to fly out of the situation; however, he was unsuccessful in stopping the yaw and struck trees, and subsequently the ground. Winds were reported at the time of the accident at 250 degrees at 10 knots, gusting to 16 knots. Examination of the helicopter revealed no evidence of any preimpact mechanical failure or malfunction, and none were reported by the pilot.

On June 5, 2007, about 1444 eastern daylight time, a Bell 206B helicopter, N912SP, crashed into a heavily wooded area while maneuvering near Cedartown, Georgia. The certificated commercial helicopter pilot and two passengers sustained serious injuries, and the helicopter was destroyed by impact forces and postcrash fire. The flight was operated as a public use aircraft, engaged in a low-level drug interdiction mission for the State of Georgia, Governor's Drug Task Force, under the provisions of 14 Code of Federal Regulations (CFR) Part 91, with no flight plan filed for the local flight. Visual flight rules (VFR) conditions prevailed at the time of the accident. The flight departed from Cornelius-Moore Field (4A4), Cedartown, Georgia, at 1415.

The pilot stated to a National Transportation Safety Board investigator that at the time of the accident, they were over a forested area in hilly terrain, about 50 miles west-northwest of Atlanta. He estimated that his altitude was between 250 and 300 feet above trees varying in height from 30 and 50 feet. The pilot reported that while flying low over trees in a left turn, a strong gust of wind was encountered causing the helicopter to yaw to the right, which developed into a right spin he could not arrest with the application of full left pedal. He lowered the collective to slow the rotation and the helicopter descended out of control to the ground. The pilot reported no airframe or engine anomalies prior to the accident.

Examination of the accident site by a Federal Aviation Administration FAA Inspector found that the helicopter had impacted into and between trees in a near vertical attitude. The helicopter came to rest on a 305-degree magnetic heading. Examination of the wreckage found very little of the helicopter remaining.

The fuselage of the helicopter sustained substantial impact and postcrash fire damage. Due to the location, and the reportedly near full fuel cell, the fire department allowed the helicopter to burn itself out, while the resulting forest fire was contained. Most of the fuselage was consumed by the fire, and the portions of the fuselage that were not consumed remained unremarkable.

Examination of the mast and planetary gear from the main transmission, main rotor head, tail rotor gearbox, turbine, compressor, and engine deck were among the largest recognizable remnants of the wreckage. The engine accessory gearbox was consumed by fire. The power take-off (PTO) gear from the accessory gearbox remained attached to the freewheeling unit on one end and the number one tail rotor drive shaft on the other. The three components were securely connected. The exterior surfaces of the compressor and turbine assemblies exhibited discoloration, heavy sooting, and molten material deposits as evidence of exposure to very high temperatures. All of the fuel, oil, and pneumatic air lines on the exterior of the engine were either destroyed or sustained heavy damage. The insulation on the electrical conductors on the exterior of the engine were completely burned away. The pneumatic accumulator and power turbine support external scavenge oil sump can were the only recognizable components among the molten material on the underside of the horizontal fire shield beneath the turbine assembly. Both the turbine shaft to pinion gear and turbine to compressor couplings were properly installed and absent of visible damage. Both the gas producer and power turbine assemblies turned with noise and resistance when actuated by hand using the respective turbine shaft to pinion gear and turbine to compressor couplings. At the conclusion of the examination no evidence of any preimpact mechanical failure or malfunction was found.

The 1500 surface weather observation at Hartsfield Jackson Atlanta International Airport (ATL), Atlanta, Georgia, was: wind 250 degrees at 10 knots, gusting to 16 knots, visibility 10 statute miles, few clouds at 4500 feet, scattered clouds at 11000 feet, temperature 82 degrees Fahrenheit, dew point temperature 57 degrees Fahrenheit, and altimeter 29.80 inches of mercury.

The pilot was issued a Pilot/Operator Report but had not completed it at the time of this report.