PRESCOTT, Ariz. -- Fire crews battling a wildfire should identify escape routes and safe zones. They should pay close attention to the weather forecast. And they should post lookouts.
Those are standards the government follows to protect firefighters, which were toughened after a wildfire tragedy in Colorado nearly two decades ago. On Tuesday, investigators from around the U.S. were arriving in Arizona to examine whether 19 highly trained firefighters who perished over the weekend heeded those rules or ignored them and paid with their lives.
In the nation's biggest loss of firefighters since 9/11, violent wind gusts Sunday turned what was believed to be a relatively manageable lightning-ignited forest fire in the town of Yarnell into a death trap that left no escape for the team of Hotshots willing to go to the hottest part of the blaze.
The tragedy raised questions of whether the crew should have been pulled out much earlier and whether all the usual precautions would have made any difference at all in the face of triple-digit temperatures, erratic winds and tinderbox conditions that caused the fire to explode.
In 1994, 14 firefighters died on Colorado's Storm King Mountain, and investigators afterward found numerous errors in the way the blaze was fought. In the Storm King tragedy, a rapid change in weather sent winds raging, creating 100-foot tongues of flame. Firefighters were unable to escape, as a wall of fire raced up a hillside.
The U.S. Forest Service revised its firefighting policies as a result of the blaze.
"The reforms after Storm King were collectively intended to prevent that from happening again, which was mass entrapment of an entire Hotshot crew," said Lloyd Burton, professor of environmental law and policy at the University of Colorado.
"There are so many striking parallels between this tragedy and what happened on Storm King in 1994, it's almost haunting."
Those changes included policies that say no firefighters should be deployed unless they have a safe place to retreat. They must also be continuously informed of changing weather.
"If you don't have those things in place, it's not advisable to deploy a team in the first place, because you can't guarantee their safety," Burton said.
The Hotshot team from Prescott entered the smoky wilderness over the weekend with backpacks, chain saws and other heavy gear to remove brush and trees and deprive the flames of fuel.
But the blaze grew from 200 acres to about 2,000 in a matter of hours as "the wind kicked up to 40 to 50 mph gusts and it blew east, south, west -- every which way," said Prescott City Councilman Len Scamardo.
"What limited information we have was there was a gust of wind from the north that blew the fire back and trapped them," Scamardo said.
The crew's only surviving member, Brendan McDonough, was on a hill top working as the lookout when the winds picked up, said Wade Ward, spokesman for the Prescott Fire Department.
McDonough notified the other Hotshots that the weather was changing rapidly and that the fire had switched direction because of the wind. McDonough also told his fellow crew members that he was leaving the immediate area because he was in danger and asked them if they needed anything.
"He did exactly what he was supposed to," Ward said Tuesday of McDonough, who was in his third season with the unit.
Retired smoke jumper Art Morrison, a spokesman for the Arizona State Forestry Division, said it's essentially a judgment call as to whether a spot can work as a safe haven to escape to if the flames suddenly blow toward crews and they have to flee for their lives.
"Whatever they used as a safety zone just didn't work," he said.
Dick Mangan, a retired U.S. Forest Service safety official and consultant, said it is too early to say if the crew or those managing the fire made mistakes.
"This just might have been a weather anomaly that nobody saw coming that happened too quickly to respond to," Mangan said.
He said the crew members might have taken too many risks because they were on familiar ground and were trying to protect a community they knew well.
"When you've got especially structures and residences involved, and you've got local resources, there's a fair amount of social and political pressure, some of it self-generated by the firefighters, who want to do a good job," Mangan said. "They don't want to see a community burn down. They want to get in there."
A team of fire officials drawn from across the country by Atlanta NIMO, or National Incident Management Organization, arrived in the area Tuesday to find out exactly what went wrong.
They plan to make their way into the charred fire scene and issue a preliminary report in the coming days, said Mary Rasmussen, a spokeswoman for the Southwest Area Incident Management Team.
With the investigation just beginning, it's not clear what help water- or retardant-dropping aircraft could have provided for the doomed crew.
One contractor, Neptune Aviation Services, had three aerial tankers making drops on the fire earlier in the day. But at the time the firefighters died, the planes had been grounded because of treacherous conditions, said chief executive Ronald Hooper.
"It wasn't safe for them to be in the air at that time," Hooper said. There were "severe winds, erratic winds and thunderstorms in the area."
Weather reports from around the time of the firefighter deaths show how volatile the wind became. At 4 p.m., the wind was blowing out of the southwest, but one hour later, it had switched to the exact opposite direction and dramatically increased in speed. It was gusting at 22 mph at 4 p.m. but was at 41 mph by 5 p.m.
However, government dispatch logs show at least two other planes were flying over the fire at the time, one large tanker and one small one. There was also at least one firefighting helicopter in the air early Sunday afternoon.
On Tuesday, about 500 firefighters were battling the mountain blaze, which had burned about 13 square miles. Yavapai County authorities said about 200 homes and other structures burned in Yarnell, a town of about 700 people. Hundreds were evacuated.
Wind even more powerful than the gusts that hit Sunday were forecast for Tuesday, said National Weather Service meteorologist Jim Wallmann.
No part of the fire had been contained.
Fire Cmdr. Clay Templin said the wildfire was "still burning very hot" even though there were not a lot of active flames. Complicating efforts were the "exceptionally" dry conditions from drought.
"Whether it's brown or green, everything burns right now," Templin said of foliage.
He urged residents to heed evacuation orders, saying "in these extraordinary conditions, we don't want to have another tragedy in Arizona."