ANC95LA020

The air taxi pilot reported he departed st. Mary'S airport with one passenger aboard. He said he was flying about 600' AGL along the south bank of the yukon river, when opposite direction traffic reported inbound to st. Mary'S, also flying along the south bank. The pilot said he elected to transition to the north bank to avoid traffic, but soon encountered deteriorating weather conditions. He said forward visibility rapidly diminished, and he entered whiteout conditions. While trying to keep visual contact with the shoreline and trees, he said he inadvertently allowed the airplane to descend until it struck snow covered terrain.

On December 13, 1994, at 1310 Alaska standard time, a wheel equipped Cessna 207 airplane, N7340U, operated by Hageland Aviation Services, Inc., collided with terrain approximately two miles north of Saint Mary's, Alaska. The airline transport certificated pilot-in-command, and the one revenue passenger on board the flight were not injured. The airplane sustained substantial damage. The 14 CFR Part 135 extra section flight departed Saint Mary's at approximately 1308 and the intended destination was Mountain Village, Alaska. A company visual flight rules (VFR) flight plan was in effect, and instrument meteorological conditions prevailed at the time of the accident.

On December 14, 1994, the NTSB investigator-in-charge conducted a telephone interview with the pilot of N7340U. The pilot said that the flight departed Saint Mary's on runway 34 and that he proceeded to visually navigate along the left bank (south side) of the Yukon River. Another flight reported on the common radio frequency of flying along the south side of the river but in the opposite direction. The pilot said that due to the poor visibility and the collision potential, he elected to transition across the river to the north shore. There was less vegetation along the north bank with which to use to maintain perspective with the ground. While the flight moved across the river, the pilot lost the ability to maintain level flight solely by reference to outside references and inadvertently allowed the airplane to descend. The plane struck the frozen surface of the river in a near level attitude damaging the propeller, the nose gear, and the firewall.

The pilot said that white out conditions prevailed at the time of the accident. He estimated the ceiling to be between 300 and 500 feet obscured with light snow fall.