Skwentna, AK, USA
N146ET
Hiller UH-12E
The solo commercial certificated pilot was attempting an off-airport landing on rough/uneven terrain under Title 14, CFR Part 91. The pilot reported that he was attempting a toe-in landing to pickup passengers, and about one foot above the ground he heard a loud bang, and the helicopter yawed to the right. The tail rotor separated from the helicopter, and the helicopter descended uncontrolled, impacting the ground, damaging the tail rotor, tail boom, fuselage, and main rotor system. During a postaccident inspection of the site, the pilot reported finding an area of disturbed snow, where the tail rotor struck the glacier. He described the conditions as wind shifts up to 180 degrees, gusting 10-15 knots, density altitude 7,000 feet, and marginal flat light on a snow-covered glacier. A passenger waiting to be picked up reported that it looked like a gust of wind pushed the tail of the helicopter to the right, and the tail rotor struck a snow bank.
On July 9, 2007, about 1610 Alaska daylight time, a Hiller UH-12E helicopter, N146ET, sustained substantial damage during an impact with terrain, following a tail rotor strike while attempting to land on a glacier, about 60 miles west of Skwentna, Alaska. The helicopter was being operated by Prism Helicopters, Wasilla, Alaska, as a visual flight rules (VFR) positioning flight under Title 14, CFR Part 91, when the accident occurred. The solo commercial certificated pilot was not injured. Visual meteorological conditions prevailed, and company flight following procedures were in effect. During a telephone conversation with the National Transportation Safety Board (NTSB) investigator-in-charge (IIC) on July 9, the director of operations for the operator said the helicopter was stationed at Terra Camp, which is a mine site west of Skwentna. She said the helicopter left Terra Camp to pickup passengers at a drill-pad site at the 6,000 foot elevation above the camp. According to a passenger waiting at the drill site for the helicopter, she was told that it looked like a gust of wind pushed the tail of the helicopter to the right, and the tail rotor struck a snow bank. She said the tail rotor separated from the helicopter, and the helicopter descended uncontrolled, impacting the ground. She reported damage to the helicopter's tail rotor, tail boom, fuselage, and main rotor system. In a written statement to the NTSB dated July 9, the pilot wrote that he was attempting a toe-in landing to pickup passengers. He reported that about one foot above the ground he heard a loud bang, and the helicopter yawed to the right. He landed and secured the helicopter. Inspecting the site, he reported he found an area of disturbed snow where the tail rotor must have struck the glacier. In his statement, the pilot described the conditions as wind shifts up to 180 degrees, gusting 10-15 knots, density altitude 7,000 feet, and marginal flat light on a snow-covered glacier.
The pilot's failure to maintain clearance from a glacier, which resulted in a tail rotor strike during landing, and damage to the helicopter during an emergency descent/landing on rough/uneven terrain. Factors contributing to the accident were variable and gusty wind conditions.
Source: NTSB Aviation Accident Database
Aviation Accidents App
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