PHOENIX – An Arizona wildfire was so out of control because of winds from a nearby thunderstorm that officials asked for half the available western U.S. air-tanker fleet nearly an hour before 19 members of a hot-shot crew were killed, records obtained by the Associated Press on Friday show.

The records from the federal Bureau of Land Management show Arizona officials asked for six heavy air tankers at 4:08 p.m. June 30, about 50 minutes after outflowing high winds from a nearby thunderstorm began driving the wildfire toward the small town of Yarnell. National Weather Service officials issued a wind warning to fire managers at 3:26 p.m. that day. The firefighters radioed that they were trapped and getting into the emergency fire shelters at 4:47 p.m.

The six planes were never deployed or arrived because of the limited number of tankers in the nation’s aerial firefighting fleet and the dangerous weather conditions at the time. Fire officials said even if they had been available winds were so strong they couldn’t have been used to save the firefighters’ lives.

But the fact that so many planes were requested provides more proof that firefighters were facing an increasingly dangerous scenario. There were only 12 heavy tankers available that day in the western U.S.

“It is significant, and it makes an exclamation point to the situation, doesn’t it,” said Jim Paxon, a spokesman for the Arizona Division of Forestry, which was managing the fire.

The agency asked for the six heavy tankers when the thunderstorm started kicking up fire activity but they didn’t get them because none were available. This was nearly an hour before out of control flames trapped the 19 members of the Granite Mountain hotshots and lead to the nation’s worst wildland fire tragedy since 1933.

Despite the size of the order and what the state Forestry Division says was the dire danger to the town, there was no sign crews were in immediate danger. There also wasn’t any sense of urgency conveyed when the air tankers were ordered, federal officials said.

Don Smurthwaite, a spokesman for the National Interagency Fire Center in Idaho, described the request for six large tankers as “coincidental and not consequential” to the fate of the doomed hot-shot crew.

He said none of the dispatch records related to the request show “any expression firefighters were in trouble.”

“We did not know at this level how much jeopardy the Granite Mountain Hotshot crew was in,” said Smurthwaite, whose agency oversees the deployment of firefighting aircraft in wildfires.