JUNEAU, AK, USA
N39GT
AEROSPATIALE AS-350
THE PILOT STATED HE LANDED ON THE GLACIER WHERE HE NORMALLY LANDED, 'IN THE SAME TRACKS.' WHILE HE WAS LEANING OUT THE DOOR TO CHECK THE POSITION OF THE SKIDS THE HELICOPTER NOSED DOWN AND THE MAIN ROTOR BLADES CONTACTED THE SURFACE OF THE ICE WHICH CAUSED THE HELICOPTER TO PIVOT 180 DEGREES ABOUT THE NOSE. EXAMINATION OF THE LANDING AREA SHOWED A DEEP CREVASSE, IN THE AREA OF THE RIGHT SKID'S LANDING POSITION, THAT WAS FILLED WITH CLEAR WATER. THE TOE OF THE RIGHT SKID HAD NO ICE TO REST ON AND FELL INTO THE CREVASSE.
HISTORY OF FLIGHT On July 19, 1994, at 1650 Alaska daylight time, a skid/ski equipped Aerospatiale, AS-350 Helicopter, N39GT, registered to Geneva Aviation Inc., of Everett, Washington, and operated by Temsco Helicopters, Inc., rocked up on its nose, struck its main rotor blades on the ice, rotated 180 degrees, and slide backwards into a depression after landing on the Herbert Glacier, located approximately 20 miles northwest of the Juneau Airport, Juneau, Alaska. The Air Taxi sightseeing flight, operating under 14 CFR Part 135, departed the Temsco Helipad on the Juneau Airport and the destination was the Herbert Glacier. The helicopter received substantial damage and the pilot and the six passengers were not injured. According to the pilot, he landed on the ice where he normally lands, "in the same tracks." He pulled the fuel flow lever to the idle position, frictioned the cyclic and latched the collective with his left hand. He opened his door and leaned out to take a look at the position of his skids. The pilot stated he was moving "back into the cockpit" but still looking through the gap in the front door when the helicopter began to nose down. He saw the main rotor blade strike the ice in front of the helicopter. The helicopter's nose continued downward and the entire helicopter then began to pivot to the right around the nose of the helicopter which was now resting on the ice. The pilot stated that he placed the right skid next to a puddle on the ice during the landing. He stated the puddle was too large to step across but there was room to stand on the ice between the skid and the puddle. He was leaning out to check the skid to ensure that the heel and toe of the skid were firmly placed on the surface. ADDITIONAL INFORMATION The on site examination of the landing area and accident site showed that there was a water filled crevasse shaped in an "H" shape. The left side, based upon the direction of landing had solid ice beneath approximately 2 inches of water. The center of the "H" was a thin rivulet of water connecting the shallow puddle with the puddle on the right. This puddle was very deep and was filled with clear water. The depth of the crevasse was estimated in excess of 15 feet. The forward portion of this crevasse was chipped and covered with paint chips of the same color as the helicopter. Approximately 10 feet directly in front of this crevasse were a series of gouges determined to have been caused by the main rotor blades striking the ice. Further examination of the surface of the ice in the landing area shows the ice to be white in color and opaque. It was extremely difficult to determine the thickness of the ice by visual inspection. According to other pilots, who have numerous take offs, landings, and operations on the surface of glaciers, the white opaque ice will melt when pressure is applied, such as the weight of the aircraft. When the same area is used over and over, the ice will become worn. The condition or relief of the ice beneath the surface can never be known because the glacier is constantly moving and crevasses are opening and closing as a result of that movement. The pilot stated that the passenger sitting next to him, who could have reached the collective, did not pull up on the collective. All the passengers were still seated with their seatbelts fastened.
THE PILOT'S SELECTION OF UNSUITABLE LANDING TERRAIN. A FACTOR WAS THE CREVASSE IN THE ICE.
Source: NTSB Aviation Accident Database
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