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Uncrewed Aerial Systems (UAS), or drones, are another tool which can be used during wildland fire operations.

A UAS module arrived on the Camp Creek Fire on September 2 to provide the incident management team with a better day-to-day large scale view of the fire through a live video camera feed. It can also assist with more accurate acreage reporting through infrared mapping. A specialized use of the device is to assist with firing operations, a process known as aerial ignitions because the application of fire comes from above rather than from firefighters on the ground.

If fire needs to be applied into areas firefighters cannot access on foot, they can carry small plastic spheres filled with potassium permanganate. The spheres are injected with glycol and dropped from the UAS. The combination of the glycol with the chemicals creates heat that ignites the spheres as they near the ground. Operators can release the spheres with a high degree of accuracy in terrain difficult to access on foot.

UAS operators identify units where fire will be introduced. They then create grids within each unit which the UAS will fly in a back-and-forth pattern. The grid is outlined with a geofence which reinforces that the UAS stays within the predefined boundary.

A helicopter can also be used for aerial ignitions and carry a larger load of the plastic spheres. Though a UAS needs to return more frequently to be resupplied with spheres, it has a safety advantage over a helicopter because, in the event of a mechanical failure, no personnel are at risk in an unmanned piece of equipment. A UAS also has the capacity to fly at night and conduct aerial ignitions when conditions may be more favorable.

There is a Temporary Flight Restriction (TFR) over the fire area, which includes public drone use. Illegal drone use in a TFR area can halt critical air resource support on the fire and compromise the safety of firefighters and other personnel working the fire.

Click each of the captions below to see images of the UAS and spheres. 

• A metal box is attached to the bottom of a UAS. It contains both the spheres and a canister of glycol that will be injected into the spheres to initiate combustion
   
• Two UAS crew members attach a sphere container to the bottom of a drone in preparation for aerial ignitions 
   
• Two UAS crew members replace the battery on the drone in order to continue firing operations
   

Note: The second and third photos above show two members of the Uniweep Fire Module from a fire earlier this season in Colorado. A similar crew and UAS arrived at the Camp Creek Fire on September 2.