Wasilla pilot Paula Huckleberry, 61, was flying to McGrath with two passengers -- 21-year-old Scott Stevenson of Idaho and 39-year-old Chris Fontes of Arizona -- when the helicopter went down two or three miles outside the village, troopers said.
The helicopter was returning to McGrath from a mining operation 15 miles to the southwest, said National Transportation Safety Board investigator Clint Johnson.
Early information from Soloy Helicopters of Alaska, which operates the Hughes 500, indicated the helicopter's single engine failed about 7:20 p.m., Johnson said. It's unclear how high the chopper was flying when the problems began, he said.
Huckleberry had to use an emergency landing technique known as autorotation, the investigator said.
"You're using the inertia that's in the rotor system to keep the machine airborne, but under control," Johnson said. "It's an emergency procedure practiced day in, day out. You start doing that from the first day you start flying helicopters."
The chopper's rotor blades struck trees on the way down, Johnson said. Troopers said the helicopter was badly damaged.
Huckleberry either had a satellite phone or working radio gear to communicate that no one had been injured, Johnson said.
An emergency locator beacon transmitted the downed helicopter's location, near the Kuskokwim River. The Air National Guard's Rescue Coordination Center notified troopers, who responded by boat from McGrath, troopers said.
Rescuers found Huckleberry, Stevenson and Fontes uninjured on the bank of the Kuskokwim, troopers said. All three were taken to McGrath by boat, troopers said.
Johnson said he would be looking into why the helicopter's engine failed.
Soloy Helicopters did not immediately return a call seeking comment.
Reach Casey Grove at casey.grove@adn.com or 257-4589.
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