In this June 30, 2013, file photo, the Yarnell Hill Fire burns in Glenn Ilah near Yarnell, Ariz. Investigators are set to release a report Sept. 28, 2013, on the deaths of 19 elite firefighters in Arizona.
Photo credit: AP Photo/The Arizona Republic, David Kadlubowski, File
In this July 23, 2013 file photo, Prescott Wildland Division Chief Darrell Willis touches a Granite Mountain Hot Shots crew shirt draped over a burned cactus, in Yarnell, Ariz.
Photo credit: AP File Photo/Matt York
In this July 2, 2013 file photo, firefighter Brendan McDonough embraces a mourner near the end of a candlelight vigil in Prescott, Ariz. McDonough was the sole survivor of the 20-man Granite Mountain Hotshot Crew.
Photo credit: AP Photo/Julie Jacobson, File
PRESCOTT, Ariz. (AP) — A highly anticipated report examining weather conditions, radio traffic and fire behavior, among other things, is expected to help explain how 19 members of an elite firefighting crew died while battling an Arizona wildfire. Officials, however, said it won't assign blame.
The Arizona State Forestry Division was set to present the roughly 120-page report to the men's families ahead of a news conference planned for Saturday morning in Prescott.
All but one member of the Granite Mountain Hotshots crew died June 30 while protecting the small former gold rush town of Yarnell, about 80 miles northwest of Phoenix, from an erratic lightning-sparked wildfire.
Early reports showed the fire caused little immediate concern because of its remote location and small size when it began June 28. But the blaze quickly grew into an inferno, burning swiftly across pine, juniper and scrub oak and through an area that hadn't experienced a significant wildfire in nearly 50 years.
The 20-member Granite Mountain Hotshots team arrived early on the morning of June 30 and headed into the boulder-strewn mountains. About nine hours later, the crew radioed that they were trapped by flames and deploying emergency shelters. Only one crew member who was assigned as the lookout survived.
The fire ended up destroying more than 100 homes and burned 13 square miles before it was fully contained on July 10.
No other wildfire had claimed more firefighters in 80 years, and it was the deadliest single day for fire crews since the terror attacks of Sept. 11, 2001. The Granite Mountain team was unique among the nation's roughly 110 Hotshot crews as the first and only such unit attached to a municipal fire department.
It wasn't clear why the firefighters left the relative safety of a ridge top or if they had received warnings of the erratically changing weather that whipped the blaze into an unpredictable inferno when they dropped down into a bowl surrounded by mountains on three sides.
At one point, officials asked for half of the available western U.S. heavy air tanker fleet — six planes — to try to control the blaze. Five weren't deployed because of the limited number in the nation's aerial firefighting fleet and the dangerous weather conditions at the time. One plane was heading to Arizona from California but engine problems forced it to turn back.
Forestry officials have said that even if the planes had been available, winds were so strong they couldn't have been used to save the firefighters' lives.
Some family members hope the investigation will explain why their loved ones died. Others say it will do nothing to ease their pain.
"No matter what the report says, it won't bring him back," Colleen Turbyfill said of her son, Travis. "I miss him, and it's unbearable pain. It doesn't go away. Sometimes I can't breathe, but this report isn't going to help that one way or another."
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