Fighting forest fires with fire: Pyrotechnics and flaming Ping-Pong balls

This story is part of World on Fire, a five-part podcast that takes us to the front lines of out-of-control wildfires in Canada, Australia and California. Recorded during the COVID-19 pandemic, each episode examines what it takes to find hope in the midst of fear and destruction. Wildfires cost us our health, our homes and our communities, yet people everywhere rebuild and not just survive — but thrive.

Kevin Parkinson ignites slow-burning forest fires with a special kind of ammunition — thousands of tiny fireballs shot from the air into the trees below.

Spewed from the mouth of a metal box, the spheres cascade through the treetops before hitting the forest floor and bursting into flame.

The process involves items that look like Ping-Pong balls, and "the Ping-Pong balls are filled with potassium permanganate," Parkinson said. The machine injects glycol — antifreeze — into each ball before dropping it onto the ground.

"After about 25 to 30 seconds, it creates a chemical reaction inside the ball and the ball will catch on fire," said Parkinson, in an interview for the CBC podcast World on Fire.

Parkinson, a wildfire operations officer based in Slave Lake, Alta., is one of the few people in the province trained in the complex physics of prescribed burns.

Prescribed burns are done across Alberta every year to help eliminate potential fuel for wildfires, including dead wood and underbrush. The scorched areas left behind often serve as a barrier between the forest and residential communities.

'A planned wildfire'

The machine Parkinson often uses to ignite these fires is called an aerial ignition device. A fully automated contraption that hangs from the belly of a helicopter, the equipment is useful in remote expanses of forest or grassland too difficult or dangerous to reach on the ground.

The technology isn't exactly cutting-edge, but it works.

"This piece of equipment, the first one came around in 1970," Parkinson said. "They have upgraded some features and designs on it, but overall the concept is pretty close to what was originally developed.

"You can put this piece of equipment in the back of the helicopter with you and when you have 20,000 balls, then you can go all day."

Parkinson is a nationally certified ignition specialist, one of only 10 in Alberta, with 14 years of experience orchestrating wildfires. He is a member of a special provincial aerial ignition team.

Fires are part of the natural cycle of the boreal forest. Old stands of trees that have been left untouched for too long can be tinderboxes. By bringing new growth to the forest floor, prescribed burns can help restore the boreal habitat and reduce the wildfire risk.

"We do lots of small hazard-reduction burning every spring and fall around communities," Parkinson said.

"Some are larger-scale prescribed burns, some of them are to bring back habitat for elk or bighorn sheep. 

"Basically, it's a planned wildfire. I've been involved in some of the larger burns here in Alberta. Some of them have lasted two or three days."

No room for error

Prescribed burns can also help during the peak of Alberta's wildfire season — hot, dry summers that have become increasingly susceptible to uncontrolled fires. 

When the flames become so intense that air tankers can no longer fly, Parkinson and his crew can manipulate the flames —  by setting smaller, more strategic fires, he can push a wildfire in a safer direction or even force it to travel toward natural fire breaks like lakes and rivers. 

Sometimes, a more intense fire is needed than the ones generated by fireballs injected with anti-freeze. That's when Parkinson will pull out a heli-torch.

The 45-gallon drum hangs below a helicopter like a pendulum, shooting globs of a lava-like liquid into the forest.

"We put our burn fuel and our gelling agents in the drum and then it hooks up to the helicopter," Parkinson said.

The drum "hangs about 22 feet below the helicopter and as we're flying, when the pilot hits an ignition switch, it engages a pump and also the propane, which lights the fire.

"Then the gel will fall down through the fire and fall down through to the trees. This allows you to get more intense fire behaviour faster."

'We don't rush'

With all these dramatic pyrotechnics, Parkinson's work requires surgical precision. For larger fires, a central command centre manages the work of tactical teams on the ground.

Crews are deployed, but only after every aspect of the fire's potential behaviour in the landscape has been carefully accounted for.

Parkinson must assess the terrain and weather conditions. It's a careful study — winds blowing too hard or in the wrong direction, for instance, could prove dangerous. A lack of humidity could create critical intensity.

The fire must not reach beyond the containment area. The planning involved in a single prescribed burn can take months, even years.

"There is a lot of prep work," Parkinson said. "I did a prescribed burn down in [the town of] Rocky Mountain House. That burn plan was on the books for 10 years to get the right conditions for us to be able to do it. 

"We don't rush trying to do these prescribed burns. We have to make sure all the right parameters are in place before we go out."

With 26 wildfire seasons under his belt, Parkinson has come to appreciate the phrase "fighting fire with fire."  

But there is a difference between an orchestrated burn and one that has taken on a life of its own.

With a prescribed burn, "everything is planned in detail," he said. "You're more proactive than reactive. With a wildfire, you never know what's going to occur."