On June 9, 2003, about 1145 Alaska daylight time, a wheel-ski equipped Cessna 185 airplane, N5246E, operated by Talkeetna Air Taxi, Talkeetna, Alaska, as a Title 14, CFR Part 135 sightseeing flight, received substantial damage when it nosed over during an aborted takeoff from the Mountain House airstrip on the Ruth Glacier, located in the Denali National Park, and about 30 miles north-northwest of Talkeetna, Alaska. The airline transport pilot received minor injuries; the four passengers were not injured. The flight operated in day visual meteorological conditions, and company flight following procedures were in effect. The local flight departed Talkeetna about 1145, for a sightseeing flight in the vicinity of Mount McKinley. During a telephone conversation with the NTSB investigator-in-charge on June 10, the pilot related that he was attempting a down-slope takeoff from the glacier air strip. He described the snow as fresh and wet, which slowed the airplane's acceleration. He said he elected to abort the takeoff because of the slow acceleration and low airspeed. As the airplane approached the end of the takeoff area, he initiated a turn to the left, to return up-slope to the takeoff area. As the airplane entered the turn, he said it felt like the right wheel-ski encountered a soft spot, or perhaps a sink hole, and sank deeper into the snow. He said as soon as the wheel-ski sank, the airplane nosed over. The airplane received structural damage to the fuselage and right wing. On June 10, a federal park ranger flew to the accident site and observed the airplane upside down, and facing up-slope, in the opposite direction of the takeoff run. An excerpt from his written report notes: It was observed that the tail wheel had not touched down before the plane flipped. The accident appeared to have been triggered as soon the plane started to turn. The accepted procedure when you cannot take off on a glacier is: 1. Come to a complete stop going straight. 2. Unload the passengers. 3. Make the turn. 4. Taxi back up with or without the passengers.