A Washington state man said he relied on skills he learned as a Boy Scout to help him survive two cold nights in the Idaho mountains after becoming lost while skiing.

Air Force Col. Mark Siefert, 45, of Redmond, Wash., "tired and dirty" but unharmed, made his way to the base of a chairlift at Bogus Basin ski resort at about 1:30 p.m. Tuesday. He had been the subject of massive search effort ever since disappearing while skiing with a friend 48 hours earlier."We made it out," Siefert said. "It was pretty interesting going, but we made it. Sometimes, though, I questioned that we would."

Siefert, who had come to the resort to watch his son Scott, 16, ski in Sunday's Cranston Cup Race, was last seen about 1:30 p.m. Sunday. While skiing Shafer Butte, Siefert separated from a friend, Tom Simmons, in order to watch his son race, said resort spokesman Mowbray Brown.

"I missed the trail and created my own and ended up down a ravine," Siefert said. Realizing he was lost and that he would not be able to find his way out before dark, he decided to spend the night in the ravine and found shelter under a large log.

With temperatures dipping into the low teens at night, Siefert woke up at least once an hour and did exercises to warm himself.

The next morning, he saw what he thought was a building on Morris Mountain north of the resort and spent most of the day hiking toward it, only to find it was a large rock, he said.

From there, he was able to get his bearings, but realized he could not get out by dark, so he decided to spend another night in the ravine before walking out Tuesday.

"I wasted Monday, but by doing that I knew what my alternatives were," he said.

Meanwhile, up to 90 searchers, including local and National Ski Patrol members and Mountain Search and Rescue, combed the area with the help of snowmobiles and a helicopter from the Idaho National Guard. Siefert said helicopters passed over him several times during the two days, but they could not see him in the trees and he had no matches to build a fire to signal them.

Siefert was adequately clothed, but Brown said he had been concerned that the cold weather lessened his chances of survival.

Simmons had said Monday that Siefert was in good condition and was an excellent skier.

Siefert said that after a night's sleep he planned to head for Sun Valley, where his son will be racing. But the experience will probably alter his skiing habits somewhat, he said.

"I think I'll be less likely to ski in the powder, out in the trees and off the runs," he said.