All but one member of Arizona's Granite Mountain Hotshots crew died on June 30 in a blaze that suddenly grew in intensity

Tom Dart and agencies theguardian.com, Saturday 28 September 2013

Communications problems caused confusion moments before 19 members of an elite firefighting unit were killed by a rapidly escalating wildfire, according to an official investigation released today.

All but one member of Arizona's Granite Mountain Hotshots crew died on June 30 after they were overcome by a blaze that suddenly changed direction and grew in intensity. A report by the Arizona state forestry division found that a communications blackout of more than 30 minutes just before their deaths meant that colleagues were unaware of the team's location and intentions.

As the men deployed emergency shelters in a last-ditch bid for survival, an aircraft containing fire retardant was hovering above, waiting for instructions.

" Few people understood Granite Mountain's intentions, movements, and location, once they left the black [the burned, safer area], " the report states. " The [investigation] Team believes this is due to brief, informal, and vague radio transmissions and talkarounds that can occur during wildland fire communications."

It adds: " Radio communications were challenging throughout the incident. Some radios were not programmed with appropriate tone guards. Crews identified the problem, engaged in troubleshooting, and developed workarounds so they could communicate using their radios. Radio traffic was heavy during critical times on the fire."

The Hotshots were dispatched to protect the small town of Yarnell, about 80 miles northwest of Phoenix, which was threatened by an unpredictable wildfire that had been sparked by lightning two days earlier.

The 20-person team arrived early in the morning of June 30 and headed into the mountains. They left the relative sanctuary of a ridge top to head into a canyon surrounded on three sides by mountains. " No one realized that the crew left the black and headed southeast, sometime after 1604, " the report said.

The fire had not seemed especially dangerous at the time. But a sudden change in the weather, prompted by thunderstorms, brought strong winds that quickly whipped up the blaze and sent it towards the crew at a speed of between 10 and 12 mph.

They sent a radio message reporting that they were trapped by flames and hurriedly deployed emergency shelters at about 4.42pm. " The fire overtook them. Temperatures exceeded 2, 000 deg F and the deployment site was not survivable, " the investigation said.

The communications issues hampered attempts to help them." At the time of the shelter deployment, a VLAT [very large air tanker] was on station over the fire waiting to drop retardant as soon as the crew's location was determined, " the report said.

Only the look-out, who was stationed more than a mile away, survived. It was the worst loss of life in a single day for US firefighters since 9/11 and the deadliest wildfire for 80 years. The fire burned for nearly two weeks over 13 square miles, destroying more than 100 structures.

The 122-page report did not apportion blame for the disaster. " The judgments and decisions of the incident management organizations managing this fire were reasonable. Firefighters performed within their scope of duty, as defined by their respective organizations. The team found no indication of negligence, reckless actions, or violations of policy or protocol, " it said.