Drones, or unmanned aerial vehicles (UAVs), are expanding their usefulness in the arenas of firefighting and fire prevention, whether in a downtown business district or in fire-prone wildlands.
Among other benefits, drones can provide situational awareness, guide emergency response, and perform dangerous duties while keeping fire personnel safe. Drones provide a new solution for extinguishing fires in high-rise buildings, which can occur beyond the reach of fire nozzles and rescue ladders. Chinese autonomous aerial vehicle (AAV) manufacturer EHang has announced a large-payload intelligent aerial firefighting solution for high-rise buildings.
Urban fire stations
With a maximum flight altitude of 600 meters (1968 feet), the EHang 216F can carry up to 150 liters (40 gallons) of firefighting foams and six fire extinguisher bombs in a single trip. A visible-light zoom camera on EHang can quickly identify the location of a fire. The vehicle then hovers precisely in position and uses a laser aiming device to shoot (in succession) a window breaker, the fire extinguishing ‘bombs’ and then a full-range spray of firefighting foam.
The EHang 216F devices are expected to be deployed in urban fire stations to assist in firefighting within a 5km (3-mile) radius. Autopilot and centralized management technologies enable a fleet of the vehicles to be remotely dispatched for first response even before firefighters arrive. Multiple 216Fs can be deployed to rapidly extinguish a larger fire.
| EHang 216F devices are expected to be deployed in urban fire stations to assist in firefighting |
Fighting and preventing wildfires
Drones are also finding multiple uses when it comes to fighting and preventing wildfires. One application is to drop self-igniting ‘dragon eggs’ that spark smaller fires to trim back overgrown forests and help prevent more destructive megafires. The dragon egg system is made up of self-igniting plastic spheres – about the size of a ping-pong ball.
Dragon eggs have been an industry standard for years, usually dropped from planes or helicopters
The spheres are filled with potassium permanganate powder and injected with glycol as an igniter just as they are being dropped. The reaction sets the balls ablaze after about 30 seconds, which is enough time for them to bounce to the ground through a forest canopy. Controlling the size and scope of a managed fire is simply a matter of how many balls are dropped. Dragon eggs have been an industry standard for years, usually dropped from planes or helicopters.
Manned aviation activities
Drones provide a new approach, directed the U.S. Department of Interior and the Forest Service. In effect, unmanned aircraft are being used to battle larger wildfires by setting smaller ones first. Another use of drones to set fires involves use of ‘flamethrower’ technology. The drone carries gasoline and shoots a steady stream of fire at vegetation or other targets.
Aerial ignition using drones is aimed at supplementing manned aviation activities, not replace them, according to the Forest Service. In fact, there is a strong desire in the fire community to convert some of the missions to unmanned systems, considering the possible dangers involved. Drones can also fly better after dark and in dangerous, smoky conditions.
Disaster response strategies
The maps were used by search-and-rescue teams to spot missing persons in the area
Directing disaster response strategies and mapping the type and location of wildfire destruction are additional missions for drones in firefighting. After California’s deadly Camp Fire in 2018, drones were used on 518 different mapping flights through smoky conditions and collected 1.4 trillion pixels of data, which were stitched together into maps of the destruction.
The maps were used by search-and-rescue teams to spot missing persons in the area. Neighborhood homeowners could submit the imagery to insurance providers for rapid claims processing. The images also facilitated access to FEMA relief funds.
Assess danger levels
The benefits of unmanned vehicles have become obvious in the wake of out-of-control wildfires in Northern California and other Western states. Drones are particularly useful given how fast forest fires can get out of control and the danger to pilots and crew.
Drones can be critical during the brief window of time between when a fire starts and when it gets out of control. Situational awareness from drones can help fire crews know how to respond, including the type and amount of resources needed. Drones can also assess danger levels and help to keep crews safe and going in the right direction.