June 4 (Reuters) - Steady progress corralling New Mexico's largest ever forest fire allowed some evacuees to return home on Monday even as officials in Utah investigated an air tanker crash that caused the first two deaths among crews fighting wildfires this year.
The airplane, a Lockheed Martin P2V, went down on Sunday afternoon in the Hamlin Valley area of southwestern Utah while on a mission to drop chemical fire retardant on an 8,000-acre (3,237-hectare) blaze along the Nevada-Utah border.
Pilot Todd Tompkins, 48, and his co-pilot, Ronnie Chambless, 40, died in the crash, federal and local officials said. Both men were residents of Boise, Idaho, and were employees of a Montana-based aviation company that supplied the plane and crew under contract with the U.S. Forest Service.
The cause of the accident was under investigation, and a team from the National Transportation Safety Board was dispatched to the scene, said Don Smurthwaite, a spokesman for the federal Bureau of Land Management in Boise.
He said Tompkins and Chambless were the first firefighting personnel to perish in wildfires that have consumed more than 1,200 square miles (3,108 square kilometers) of forest, brush and grasslands nationwide so far this year, most of it in the Western states.
Still, the year-to-date tally of burned acreage across the country is running about 40 percent below average for the same six-month period over the past decade, said Ken Frederick, a spokesman for the National Interagency Fire Center in Boise.
As of Monday, firefighters were battling a total of 11 large, uncontained blazes, the majority of them in seven Western states - New Mexico, Arizona, California, Nevada, Utah, Colorado and Idaho, the agency reported.
The biggest by far is the so-called Whitewater-Baldy Complex fire, which was ignited by lightning on May 16 in the rugged high country of New Mexico's Gila National Forest and has now scorched more territory than any other recorded blaze in the state's history, over 255,000 acres (103,195 hectares) of timber.
The blaze destroyed a dozen privately owned cabins at the height of its rampage nearly two weeks ago as gale-force winds fanned flames from treetop to treetop.
But calmer winds in recent days have allowed fire crews to gain an upper hand. By Monday, they had carved containment lines around 18 percent of the fire's perimeter and were depriving advancing flames of fresh fuel by clearing smaller trees and brush that has yet to burn.
"The wind has really been in our favor the past couple of days," Fire Information Officer Tara Ross said. "It's still warm and it's still dry, but with low winds we can ... lower the intensity of the burn."
Evacuation orders were lifted on Monday for about 200 homes in and around the historic mining town of Mogollon, but about 60 cabins in the nearby community of Willow Creek, where 12 cabins and 13 outbuildings were lost on May 23, remained off-limits.
Ross said containment work was concentrated along the fire's western flank to protect the community of Glenwood and its population of about 300 people. Teams on horseback scouted areas along the eastern edge of the blaze, looking for ideal places to create new fire breaks there, she said.
Lightning strikes remained a problem, however, blamed for sparking three new fires in New Mexico on Sunday. Lightning was also blamed for the White Rock Fire that erupted on Friday in southeastern Nevada near the town of Caliente and later burned into Utah. It was that fire which claimed the lives of the two air tanker pilots. (Reporting by Jennifer Dobner from Salt Lake City and Zelie Pollon from Santa Fe; Writing by Steve Gorman; Editing by Cynthia Johnston and Vicki Allen)