Stirling was snowmobiling on Prosperous Lake near Cassidy Point, about 24 kilometres from the city. He had his seven-year-old son on the back and was accompanied by John Oldfield and his two sons.

"We were just out for a ride ... blue skies, sunshine, it was nice," Stirling said.

They decided to ride towards Tartan Rapids. Remembering that a snowmobiler had a close call in that area last year, Stirling knew he should be cautious.

With no tracks to follow, Stirling and his companions slowed to a stop and decided that, as the weather has been fairly warm, the ice should be tested.

He got off the snowmobile and walked alone to a clear patch.

"I lifted my foot to test it out and it all gave way," he recalled.

He estimated the bone-chilling water was close to three metres deep, leaving Stirling thrashing around in a hole approximately four metres in diameter.

"I thought, 'Well, I'll just push myself off the bottom and try to get up on the ice.' But there was no bottom. I was in over my head," he said, adding that his heavy, drenched clothing made it even more difficult to pull himself out.

"I couldn't even take my helmet off because I've got a chin strap. I had to keep my hands on the ice to stay above the water."

Stirling said he wasn't panicking, but he certainly realized it was a grave situation.

Fortunately, he still had two things working in his favor. First, the water wasn't part of a strong current, despite being in the vicinity of the rapids.

"If I had been sucked under the ice it would have been game over," said Stirling, who has been a snowmobiler since he was a kid. "It was pretty scary."

Second, Oldfield was once a firefighter and paramedic. He carefully manoeuvred to the edge of the hole and grabbed hold of Stirling. Although he was able to rescue his friend, Oldfield later revealed that he was more than a little apprehensive.

"He told me later that if he had gone through the ice, then you'd have three kids watching their fathers drown in front of them. There's no way the kids could have pulled us out," Stirling said.

His final saving grace was that they were only half a kilometre from his cabin. He got back safely to dry off and get warm.

Deputy fire chief Mike Lowing said the area wasn't marked because it isn't in the Yellowknife fire department's jurisdiction.

Stirling did the right thing by getting off his snowmobile to check the ice rather than trying to pick up speed and hoping for the best, said Lowing.

However, he recommended that snowmobilers avoid areas with unknown conditions. Fifteen centimetres of ice is the minimum for safety purposes.

When testing the ice, it's advisable to carry a rope that can be tied around one's waist with the other end secured to one of the vehicles, Lowing added.