The hiker who was found Thursday in waist-deep snow after being lost for two days in the Pemigewasset Wilderness was in such bad shape that he might not have survived if rescuers had not been able to lift him out with a helicopter.

“He might not have survived a carry-out – that’s three hours,” said Col. Kevin Jordan, chief of law enforcement for New Hampshire Fish and Game. “His pulse was 40, his core body temperature was in the 80s; he was hours away from death.”

Randy Willett, 53, apparently got into trouble when he fell into a brook halfway through a demanding four-day hike. Jordan said this reflected his belief that people should not hike by themselves in the White Mountains, especially not in winter.

“What a difference it would have made here if you had two people,” he said. “We don’t get two people in these situations very often – it’s always a single person. … There are so many things that can go wrong, even on a well-planned, well-executed hike.”

Jordan noted that many people in the hiking community do not share his opinion about the suitability of solo hiking, and that hiking alone has not been classified as a form of negligence that would lead the state to bill for a rescue. No decision has been made about whether to bill Willett, he said.

According to Fish and Game, officials became aware that Willett was in trouble when he was able to contact 911 at about 2:45 a.m. on Tuesday, saying he was off trail, in deep snow and feared he was becoming “delusional.”

The call was lost before his location could be determined, partly because of the way signals bounce around in White Mountain National Forest, and a second call lasted only a few seconds.

“They were calculated to be a mile and a half apart, but it was just a minute and a half between calls,” Jordan said.

Officials traced the number and were able to contact his family and found that Willett, of Manchester, had set out on Friday, more than three days before he called 911, to do a “very aggressive hike” covering four or five 4,000-foot peaks. There is still heavy snow in many valleys within the national forest, but warmer temperatures have made ice and snow crossings of waterways more treacherous than they can be in deep winter.

Rescue teams went out on foot Tuesday and Wednesday, when weather prevented observational flights, covering trails in the Pemigewasett Wilderness, but could find no trace of Willett. On Thursday a “full court press” with dozens of volunteers started to hike down drainages – vertical valleys carved by water flowing off mountains, because “that’s where people go, downhill where it’s easier to travel,” Jordan said.

The National Guard and Civil Air Patrol also conducted aerial searches. On Thursday afternoon, another very short 911 call was received from Willett, which placed him between Mount Lafayette and Mount Lincoln, east of the Franconia Ridge Trail. Willett was found by a National Guard helicopter about six-tenths of a mile from the coordinates received through 911, about a half-mile from any trail, Jordan said.

“We lowered a medic on a cable, who grabbed him and the helicopter took him” to Dartmouth-Hitchcock Medical Center in Lebanon, Jordan said.

Family members told the Union-Leader newspaper that Willett was an experienced hiker. Jordan said it appeared from the reports of rescuers that Willett was well-equipped for winter hiking.

(The Associated Press contributed to this report.)