ARIZONA—Drier, hotter days create the perfect climate for wildfires to spread violently, rushing into neighboring communities and threatening structures. Fire suppression is easiest at night when relative humidity is higher and temps are lower, but night flying requires more coordination with partners and contractors and increases the risks to pilots and crews. 

Using uncrewed aerial systems in the Southwest, as has been done in Coronado National Forest, provides unique opportunities for improved benefits to fire and fuels treatments.

Coronado National Forest is home base for Kevin Lillie, a fire prevention technician and certified UAS pilot. It is important to understand fire behavior and how to properly suppress wildfires that threaten communities, but it is equally important to know how to control and manage a prescribed fire. One goal of the Forest Service is to return fire to landscapes that were historically fire-adapted. A literal bird’s-eye view combined with LiDAR and infrared capabilities from UAS provides a huge advantage to Forest Service fire and fuel crews. Kevin Lillie described several of the benefits of utilizing UAS in the forests:

• Efficient night-flying capabilities to monitor “hot spots” during a wildfire. Hot spots are active or smoldering parts of a fire that could potentially increase wildfire spread and risks.
• Relay information using UAS instead of larger aircraft. The pilots and fire crew monitor and assess risks associated with fires from the ground.
• Perform tasks in dangerous and hard-to-reach locations with pinpoint accuracy, and ability to fly at lower altitudes than helicopters or larger aircraft.

Lillie also shared that when Fuels Teams use UAS, they free up tankers and helicopters to perform other duties and limit the associated risks with missions, takeoffs and flight time for the pilots.

Some UAS are compatible with aerial ignition devices called plastic sphere dispenser capabilities. These dispensers are capable of dropping incendiary objects from the aircraft, a function previously restricted to helicopters. Ping-pong balls, or “dragon eggs,” are filled with a chemical powder form of potassium permanganate and then injected with glycol upon release, causing a chemical reaction that ignites the ping-pongs. They are loaded into a hopper attached to larger drones and dropped.

Sean Cox, Coronado National Forest aviation officer, expressed the importance and advantages of UAS use in the Forest Service. "I personally know folks who have been lost during aerial ignition work," said Cox.

Thanks to continued support from the agency and region, the forest has increased the number of employees taking classes to become certified UAS pilots. The regional office provides long-term plastic sphere dispenser-capable UAS. These loans have made it possible for the forest to acquire a personal UAS for continued support to fire management missions. Cox is proud of the forest’s assets and hopes more projects can be accomplished using UAS.

In 2022, the Forest Service began implementing its 10-Year Wildfire Crisis Strategy, prioritizing wildfire crisis concerns in the most at-risk communities. Congressional funding and critical collaborations with partners support the Forest Service as it prioritizes the dedication of resources to create fire-adapted ecosystems and promote healthy landscapes for current and future generations.