Snow covers Mount Washington as seen from Bartlett, N.H. in 2013.  Jim Cole/Associated Press, file

SARGENT’S PURCHASE, N.H. — A team of rescuers used the Cog Railway to shave off time but it still took more than 10 hours to save a hiker in conditions that included sustained winds topping 90 mph on New Hampshire’s Mount Washington, officials said.

The hiker from Portsmouth, New Hampshire, didn’t have appropriate gear for the difficult winter conditions and continued his solo trek after he saw other groups turn around because of the dangerous gusts and wind chill of minus-52 degrees Fahrenheit, Sgt. Glen Lucas, a New Hampshire Fish and Game conservation officer, said in a statement.

The hiker reported that he’d fallen and global positioning coordinates showed he was in a ravine at approximately 4,500 feet of elevation at close to noon on Saturday, Lucas said.

Rescuers spent more than three hours warming the hypothermic hiker – stripping off his frozen clothing and equipping him with new gear – after he was eventually located in an emergency shelter near the Lake of the Clouds Hut operated by the Appalachian Mountain Club. The hiker was returned to his vehicle at close to midnight, Lucas said.

Participants included 11 rescuers from the state’s Advanced Search and Rescue Team, Androscoggin Valley Search and Rescue Team, and Mountain Rescue Service, Lucas said. The Cog Railway, which operates a special train that goes to the top of Mount Washington, mounted a snowblower and brought rescuers part-way to the location, shaving off miles of difficult hiking, he said.