Flight Details
A helicopter pilot was conducting water-dropping operations on a forest fire using a sling-loaded bucket. The flight took place at approximately 8,200 feet above mean sea level in close proximity to mountainous terrain. The density altitude was reported as about 11,600 feet. Weather conditions included high winds, gusts, turbulence, and smoke.
Accident Sequence
As the pilot approached the target area to release the water, he was unable to see the target and was advised that he had overflown it. He then maneuvered the helicopter in an attempt to reposition for a water drop after reacquiring the target. During this maneuvering, evidence indicated that the pilot inadvertently encountered a loss of tail rotor effectiveness due to unfavorable wind conditions. The helicopter began to spin to the right. The pilot attempted to recover by entering an autorotation, but before regaining control, the helicopter impacted trees, resulting in substantial damage.
Investigation Findings
An examination of the wreckage revealed no evidence of preimpact mechanical deficiencies. The pilot had substantial overall helicopter experience; however, he had no recent mountain flying experience nor any firefighting experience.