Written by Andrew Avit, US Forest Service, Pacific Southwest Region
Drones — also called UAS or unmanned aerial systems — are playing an increasingly important role in fighting wildfires by supporting operations with aerial ignition and intelligence gathering for firefighters. The biggest benefit that drones provide is that they can hover in the sky when landing manned aircraft for the safety of the pilot.
Take, for example, the FVR-90, a fixed-wing drone with a wingspan of 14 feet capable of traveling at speeds of up to 46 miles per hour with a flight time of 8 hours. They are flown at dusk only when other manned flights are stopped. The sky is theirs, and the overhead view they have of the fire is detailed and in real time.
“The way we now use UAS is pretty much complementary,” said Justin Baxter, a National Forest Service UAS operations specialist. “There are certain times when it is unsafe for us to use manned helicopters or fixed-wing aircraft, such as for night operations or under heavy smoke or strong winds.”
The drones that Baxter and his team fly are equipped with cameras that aren’t your regular cameras. They have multiple types of sensors, including infrared, that allow the team to see smoke and, at night, see thermal signatures, or thermal imaging. This allows identifying areas where fires are still active and new areas that have seen flame development, such as spot fires.
Spot fires occur when embers from the main fire are thrown into the air and pushed by the wind until they fall to the ground, creating a new fire. They are known to be difficult to identify because they are small at first and visibility is diminished by the smoke. They may occur in hard-to-reach places that are difficult for firefighters to patrol, such as steep slopes or down into sewers.
“Drones are changing that labor-intensive process of identifying these spot fires, especially when an operational area can span hundreds of thousands of acres,” Baxter said. Using drones, fire managers and incident management teams can quickly and easily scan large areas to identify fires that may be within a mile of the main fire. This enables firefighters to get in and suppress those new beginnings before they grow.
Pointing to the majestic drone to his left minutes before takeoff to fly around the ocean from the Six Rivers Lightning Complex fire near Willow Creek, California, Baxter said.
Baxter said a lot has changed since 2015 when the agency started the drone program. With each passing year, incident management teams have increasingly incorporated capabilities into their strategies.
Communication between the drone crew and the firefighters on the ground flows in both directions. The drone might fly overhead, see heat in an area, and relay the information to the Hootschute crew. Conversely, a hotshot crew can ask the UAS crew to assist in exploring an area they suspect may be active, and then view a brief from the drone in the area in question.
John Crotty worked as the Air Operations Branch Manager with the 15 Interagency Incident Management Team in California that responded to the Lightning Complex on the Six Rivers National Forest fire.
Kruti said Air Intelligence is not new to fighting wildfires, referring to the recently retired Cobra helicopter and its capabilities in Firewatch. But the implications for unmanned flight – this opens up new possibilities.
“With the Cobra, we needed a pilot and an interpreter to operate the camera and talk to people on the ground. So, we reveal two people plus a flight [to risk]But what we really needed was the vision to fly,” Crotty said.
Thick smoke on fires like a lightning complex can ground manned aircraft. This is where drones come into play, and the images they take can inform firefighters working in a large area.
“One day I heard from one of the hotshot crews there. They were in thick smoky conditions at night. With poor visibility, they couldn’t see if they had a spot fire across the line,” Crotty said. To that exact area, the drone crew was able to locate and provide precise coordinates to the firefighters who were able to check and put it out. That kind of information we would never have without these drones and that ability. Drones are the future of aviation not just for fire but for aviation in general. It is profitable for agencies to operate under the umbrella of this type of aircraft that can provide accurate and timely information to firefighters and incident management teams. And most importantly, we can do it safely.”