On October 10, 2008, about 1030 Pacific daylight time, a Bell 206B helicopter, N206CH, impacted the ground while maneuvering in hilly terrain near Cougar, Washington. The commercial pilot received serious injuries, and the helicopter, which was owned and operated by Northwest Helicopters, sustained substantial damage. The 14 Code of Federal Regulations (CFR) Part 133 rotorcraft external load flight, which departed Olympia, Washington, about an hour and fifteen minutes prior to the accident, was being operated in visual meteorological conditions. A company visual flight rules (VFR) flight plan had been filed. According to witnesses on the ground, the helicopter was hauling tree limbs uphill to a central pickup point when the load on the end of the 60-foot cable got caught in the trees that the helicopter was flying over. According to the pilot, when the load got about 20 feet above the ground, the helicopter did a "very quick" 15 to 20 degree roll to the right, and then quickly rolled back to the level position. At that time, the pilot looked outside "to see if the load was tangled," but after the accident he could not remember what he had observed. The pilot's next recollection was looking forward and slightly uphill, and that he could not move the cyclic laterally to the left from its position of about 10 degrees right of center. At that point he continued to try to fly uphill to a dirt road, but had "little control' over the helicopter. As he neared the road, the low-rotor horn came on, and shortly thereafter, at an altitude that the pilot estimated as 20 to 40 feet above the terrain, the helicopter yawed to the right and pitched nose down. At that time, according to the pilot, he knew ground impact was imminent, so he "rolled off the throttle to at least the idle position." According to the witnesses, the helicopter impacted the terrain near the bottom of a steep tree-covered ravine. Although the pilot does not remember whether he did so, the long-line was released from the helicopter prior to the impact. It was located about 75 feet from the crash site, with the end that was attached to the helicopter lying closest to the site. A Federal Aviation Administration (FAA) Inspector from the Portland Flight Standards District Office (FSDO) responded to the accident site. That individual talked with witnesses, and performed an on-site inspection of the helicopter. The helicopter was then recovered to the hangar of the operator, where it underwent a further FAA inspection. Neither the on-site nor the follow-up inspection found any indication of an airframe, engine, or flight control anomaly that would have contributed to the accident sequence.