The orange, black and white slurry bomber lumbered along the runway at Billings Logan International Aiport late Saturday morning, its belly loaded with 2,550 gallons of fire retardant.

Cleared for takeoff, the P-3 Orion slowly lifted into the air, headed for the Cascade fire west of Red Lodge. Less than a half-hour later it returned to the Billings airport to take on more of the liquid cargo and continue its firefighting effort.

The heavy air tanker, with a two-man crew, was one of two working out of Billings on Saturday - down from five earlier in the week. But the planes that load up at the air tanker base at the east end of the airport aren't just in town to battle the Cascade fire.

In the past eight days, the air tankers have dumped 186,000 gallons of fire retardant on four fires - the Cascade fire, the Echo Canyon fire near Molt, the LeHardy fire in Yellowstone National Park and the Pump Station fire two miles northwest of Divide.

On Wednesday, the planes made 25 sorties and dropped 62,000 gallons of the reddish-orange slurry.

"That's pretty substantial retardant," said Jim Hassler, air tanker base manager.

But on Tuesday they didn't fly at all to the Cascade fire, hindered by poor visibility due to the smoke, and high winds.

Last summer, slurry bombers out of Billings dropped a total of 230,000 gallons, said Hassler, who works for the Bureau of Land Management. This season has gotten off to a later start.

"It could come and go real quick," he said.

Or, it could be the start of an active wildfire season. Either way, Hassler thought Saturday was setting up to be a big day, predicting the slurry bombers could drop 50,000-60,000 gallons before the day was done.

The two slurry bombers on duty over the weekend are owned by Aero Union, out of Chico, Calif. They are part of a fleet of 19 heavy air tankers, owned by a number of private operators, that travel the country fighting fires under the direction of the National Interagency Coordination Center in Boise.

At a moment's notice, the aircraft could be directed to fly to another fire than the one it just came from, Hassler said. Or it could be transferred from one base to another, depending upon the firefighting priorities, Hassler said.

Though under some circumstances the fire retardant could be used to extinguish a blaze, more often it is a suppression tool that supplements the work of firefighters on the ground, Hassler said.

"On the line it helps slow the fire down, or can be used for structure protection," he said.

The retardant comes as a liquid concentrate, and a gallon of it is mixed with 5.5 gallons of water to form the low-viscous liquid that is pumped into the planes. Iron oxide is added to give the slurry its color, Hassler said, so it can be seen by the firefighters.

It is visible for 24 to 48 hours after it is dumped out of the planes, he said. After that, the environmentally friendly substance soaks into the ground.

Since it contains fertilizer, Hassler said, over time it actually enhances vegetative growth.

"You can tell by looking at the ground where the retardant has been dropped," he said.

The six-person crew that fills up the aircraft at the air tanker base works for Hunot Retardant, Hassler said. Crew members are responsible for mixing and loading the retardant onto the planes, taking just seven minutes to fill a heavy air tanker.

Hassler coordinates the overall work of the base, making sure the slurry bombers get in and out quickly so they can get back to fighting fires.

Since wildfires never go as planned, it helps to be ready for whatever comes up.

"Flexibility and communication is the key to this whole operation," he said.

Though he isn't out on the fire line, Hassler likes being part of a team that can extinguish the large, destructive blazes.

"It's nice to know at the end of the day if you saved a house," he said. "It's a great feeling."

Contact Susan Olp at solpbillingsgazette.com or 657-1281.

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