By Sunday, Sept. 1, the Rim Fire burning in and around Yosemite National Park had surpassed 222,000 acres (around 90,000 hectares), making it the fourth-largest wildfire in California history. But even as the Rim Fire seemed poised to eclipse previous record-setting blazes, fire managers were describing it less as an exceptional event than as typical of the “mega-fires” — large in size, extreme in behavior — that have been burning across the Western United States with increasing frequency.
Regardless of its eventual size, the Rim Fire is certain to make history in one respect: as the first sustained use of a remotely piloted aircraft (RPA) in wildland firefighting efforts in the continental U.S. Since Wednesday morning, a General Atomics MQ-1 Predator aircraft operated by the 163rd Reconnaissance Wing of the California Air National Guard has been flying above the fire for approximately 20 hours per day, transmitting real-time electro-optic (EO) and infra-red (IR) video that is helping fire managers make better decisions about how to battle the monster blaze.
“In the first 30 to 45 minutes [of viewing Predator video feed], I saw more of the fire than I had in four days of hiking it,” said Cal Fire Capt. Jeremy Salizonni, who is embedded with the 163rd on March Air Reserve Base near Riverside, Calif., around 300 miles south of where the Rim Fire is burning. Salizonni said that the detailed, real-time images transmitted by the Predator — including IR video captured at night and through dense smoke, capabilities typically beyond the reach of manned airplanes and helicopters — are making unprecedented contributions toward mapping and analyzing the fire. And he can point to tangible ways in which that information is helping ground crews stop the Rim Fire’s progression. For example, he said, “We were able to isolate, identify and act upon spot fires, that would have become extensions of the fire, in minutes, not hours.”
According to Salizonni, the large-scale use of an RPA on a major wildfire “is something we’ve been trying to figure out how [to] make happen for years.” There have been several reasons for the hold-up, including public suspicion of “drones” that are more strongly associated with targeted killings of suspected terrorists than with non-military contributions to public safety. That’s why 163rd Reconnaissance Wing Col. Dana Hessheimer insists upon the “remotely piloted aircraft” terminology, emphasizing that the Wing’s Predators are under positive human control at all times. “We’re trying to get away from the ‘drone’ hysteria,” he said.
However, there are also regulatory obstacles to employing RPAs in the National Airspace System, as the U.S. Federal Aviation Administration (FAA) has yet to authorize their widespread use. Getting permission to use a Predator on the Rim Fire was a concerted effort that involved burning “a lot of midnight oil,” according to Salizonni. After Rim Fire incident commander Mike Wilkins requested MQ-1 support, the 163rd had to seek approval from Secretary of Defense Chuck Hagel, followed by an Emergency Certificate of Authorization (COA) from the FAA. The COA puts strict limits on the routes and altitudes the Predator can fly (above the Rim Fire, it’s operating at altitudes of 18,000 to 20,000 feet mean sea level). The COA also stipulates that the Predator have a manned escort plane when it’s not over the fire or operating in restricted airspace, to help avoid conflicts with other aircraft.
In addition to airspace and altitude restrictions, Hessheimer said the Wing is operating under a Proper Use Memorandum that places strict limits on use of the Predator’s EO/IR camera capability. “We’re very limited in what we can look at,” he said, noting that the Predator’s sensor can only be deployed over the fire, not in transit.
Salizonni said the use of the Predator on the Rim Fire has yielded some surprise benefits, such as the opportunity to gain new insights into extreme fire behavior. On video from the Rim Fire, he said, “I’ve seen active crown fire runs at 0400 hours — that’s something I haven’t seen before.” The near-continuous video coverage is also providing new opportunities to enhance the safety of ground crews, by keeping real-time tabs on their position relative to the fire’s progress.
Hessheimer described the Predator as a “game changer” in the realm of wildland firefighting, noting that before the Rim Fire, “we knew what our capabilities were, but it was hard to showcase them.” Salizonni agreed, predicting a greater role for RPAs like the Predator in wildland firefighting efforts to come. “I don’t think we’ve even scratched the surface of its capabilities for public safety,” he said.