New Firefighting Technologies: Drones, Super Shelters
Evergreen International Aviation's 747 supertanker flies over California's San Bernardino airport in 2006.
The 19 firefighters who died in a blaze in Arizona on Sunday belonged to a profession where technologies are tested rigorously and tools are adopted slowly.
But there are a slew of new innovations that are in development or on the drawing board that have the potential to transform how wildfires are fought.
We asked experts about how these advances might help firefighters deal with challenging, wind-driven wildfires like the fatal blaze in Yarnell Hill, Arizona.
Better Fire Shelters
When trapped by the fire, some of the Arizona firefighters who died were forced to deploy tent-like, foil-covered structures as a last—and ultimately futile—attempt at survival.
All federal, state, and local wildland firefighters are required to carry these so-called fire shelters while battling federal fires. The fire shelters are meant as a last line of defense when facing a fire entrapment, to be used only when there are no other options.
The U.S. Forest Service (USFS) began distributing the newest generation of fire shelters in 2003. This latest version consists of an outside layer made of high-temperature resistant silica cloth and an inside layer composed of a lightweight, fiberglass scrim cloth. Both layers are laminated to aluminum foil, which is an excellent reflector of radiant heat.
The aluminum foil is "designed to slow heat transfer from the outside to the inside of the shelter," explained Tony Petrilli, project leader for the USFS Technology Program, at a press conference on Monday.
As a result, Petrilli added, current fire shelters work really well against radiant heat. But they're challenged if they come into contact with direct flames.
Flames "break down the glue much quicker than in a radiant environment," Petrilli explained. "And when you lose that aluminum foil as your barrier, it's easier for the heat to enter into the fire shelter."
The Forest Service is already testing a next-generation fire shelter model made with improved glue that can withstand direct flames.
"It would keep that aluminum foil in place longer, and keep it better sealed for a longer amount of time," Petrilli said.
Improved Wind Models
The most dangerous types of wildfires often occur during what scientists call extreme fire weather, when conditions are hot, dry, and windy.
To better combat these kinds of fires, researchers are developing computer models to simulate how wind moves across the landscape.
"We do not have a good handle on wind patterns," said Max Moritz, who runs a fire-research lab at the University of California, Berkeley.
"Computationally, it's a pretty complex and intensive problem. This is basically like fluid dynamics. You have a wind stream going across topography in three dimensions."
But thanks largely to improved modeling software, scientists can now predict wind motion on ever smaller scales. Whereas the grid cells in simulations used to be about half a mile to six miles (one to 10 kilometers) on a side, they are now much smaller—in some micro-scale models, only a few hundred meters on a side.
"The technology is improving to the point where we can actually model fairly fine-scale wind patterns, and that's important for fires because fires respond very strongly to wind," Moritz said.
"If we know that the topography—the shape of the landscape—is going to channel wind so that they're really strong here but be blocked over there, and also which direction they'll be coming out of at a particular part of the landscape, that helps us a lot in understanding how a fire might progress in a particular situation."
Precision Drops
Oftentimes, the first firefighters to reach remote wildfires are "smokejumpers" who parachute from aircraft into an inferno.
"They're usually sent out to fires when they're first detected," explained John Fehr, director of the USFS technology and development program. "It depends how big the fire is, but they might only put two jumpers onto a fire. But in a remote area where it could take a day to get there by hiking or riding horse, a smokejumper could get there in an hour."
Most of the equipment smokejumpers need to do their job—such as chainsaws or crosscut saws—are parachuted in separately. This can be dangerous, as it requires planes and pilots to fly at low enough altitudes that the cargo isn't buffeted by winds and are dropped with precision, said Keith Windell, acting fire, aviation, and residues program leader at the USFS Missoula Technology and Development Center in Montana.
"So what we're doing is looking at a couple of different ways to do precision drops from a higher altitude so the plane doesn't have to drop down so low," said Windell, who is also a former smokejumper.
One device the Forest Service is testing is a timer that would delay the opening of the parachute until a lower altitude. This would allow planes to fly at 800 to 1,000 feet (244 to 305 meters) instead of their current altitude of about 200 to 250 feet (61 to 76 meters).
"The other option is to bundle the paracargo together so we can kick out more cargo in one pass," Windell said. "That way it reduces the number of cargo runs, so overall there's less exposure."
Cue the Drones
Thomas Bewley envisions drones playing a big role in wildfire suppression in the future.
Unmanned vehicles could be especially useful for fighting fires at night, said Bewley, who directs the Flow Control and Coordinated Robotics Labs at University of California, San Diego.
"One of the most effective times to fight a fire is at night, when the winds are down and you can contain things," he explained.
"But unless you have aerial surveillance on an area and make sure that there are safe exits, then you can't have firefighting teams out."
That monitoring role is currently filled by piloted airplanes and helicopters, but in places such as San Diego, safety regulations forbid manned aircraft from coming into an area at night unless they've already flown it during the day.
Bewley argues that drones equipped with thermal cameras could do the job better and more safely.
The drones he imagines for firefighting use are more akin to military models—like the RQ-7 and Silver Fox—that have been proven in warfare than to the hobby-grade model airplanes that some companies sell.
But such drones are still too expensive. "You have to bring these machines down from $100,000 machines down to tens-of-thousands-of-dollar machines, in order them to deploy them in large numbers in the wildfire-fighting scenario," Bewley said.
To reach their full potential, firefighting drones will also have to be able to fly and work alongside manned aircraft.
"This is something that's already done," Bewley said. The military is "already operating manned and unmanned aircraft over certain areas of interest ... It's really a question of spinning off that command-and-control capability in the military setting over to the firefighting setting."
Human Endeavor
No matter how much robotic assistance future firefighters might have, Bewley believes firefighting will remain a human endeavor for the foreseeable future.
"These won't be firefighting robots—they're fire-surveillance robots," he said.
"We really want them to be like hunting dogs. We want them to go and work semi-autonomously, get the job done, and stay out of the way so the firefighting teams can go in."
Correction: A previous version of this article stated that parachute timers would allow drops from 1,000 or 1,200 feet (305 to 365 meters) instead of from the current altitude of about 500 feet (150 meters).
Ker Than
for National Geographic
Published July 2, 2013
