Drone Swarms for Firefighting—Researchers Propose a New Way Drones Can Be Used to Fight Fires
BY Zacc Dukowitz6 May 2021
The most common use for drones in firefighting today is to provide information.
By flying over an active wildfire or a building on fire, drones can relay visual and thermal data back to firefighters on the ground via a live feed, and this data can be crucial for helping fight the fire in real time.
Drones are also commonly used to collect visual data after a fire, which can be used to create an orthomosaic or 3D model of the fire’s aftermath in order to help arson investigators determine its cause.
[Related read: 7 Ways Fire Departments Use Drones in the Field]
But researchers in Italy recently proposed another way that drones can help fight fires: using them to drop water or other “extinguishing liquids” onto the flames.
A few heavy-lift drone companies have experimented with using a single big drone to carry a firehose or a large bucket of water into the air for this purpose. But these applications haven’t really taken off, primarily because they’re just not that practical.
The key distinction between these tests and the new idea is in the size and quantity of drones used.
While a single, huge drone with a heavy payload may not make that much of a difference for a fire, a swarm of smaller drones might be able to make a big impact.
How Drone Swarms Could Fight Fires
The idea of using drone swarms to fight fires was proposed recently in an academic paper entitled Drone Swarms in Fire Suppression Activities: A Conceptual Framework, which was written by researchers Patrizia Bagnerini, Marco Ghio, and Elena Ausonio.
Image credit: Danielle Rossi
The drone swarm approach to firefighting is meant specifically for fighting forest fires. The idea is that a large swarm of drones could create a constant barrage of liquid, essentially acting like man-made rain.
We propose an innovative forest firefighting system based on the use of a swarm of hundreds of UAVs able to generate a continuous flow of extinguishing liquid on the fire front, simulating the effect of rain.
– Drone Swarms in Fire Suppression Activities
According to the paper, the drones would operate as a single network, following a grid pattern to ensure full coverage of the targeted area.
Although manned aircraft (i.e., helicopters and airplanes) can be used to drop water on active fires, drones present several advantages:
- Flexibility. Drones are much more flexible regarding takeoff and landing locations.
- Speed of deployment. Drones can be deployed more quickly, allowing for a faster response than manned aircraft.
- Fewer operational limitations. Drones can operate at night or during the day and can fly regardless of visibility issues.
- Customizable. Drones can be customized to the specific situation—that is, you can make a swarm bigger or smaller depending on the size of the fire you’re fighting.
- No lives risked. If you’re not putting pilots in the sky to fight a fire, you’re not risking their lives.
- No water refueling limitations. Drones that use extinguishing liquids instead of water don’t require the presence of a water basin nearby.
The last point is one of the most important.
The ability of manned aircraft to fight a fire can be severely limited by its proximity to a water refueling site. If the nearest site is a long distance away, the craft will only be able to perform so many water drops per hour on the fire, thus limiting the craft’s overall effectiveness in fighting it.
On the other hand, drones equipped with extinguishing liquids could refuel quickly on-site and get right back in the air, with no extra time wasted going to re-up on water.
Testing the Idea
The idea of using drone swarms to simulate rain over a wildfire sounds great—but will it actually work?
To demonstrate its effectiveness, the researchers used a predictive model that computed how a fire might move through scrub in the Mediterranean.
Researchers applied estimates to this model for how many feet of fire could be extinguished by a drone swarm, making calculations based on the number of drones and the amount of extinguishing liquid each one carried.
Image credit: Danielle Rossi
The outputs from these models predict that a drone swarm could provide “the flow of water required to fight low-intensity and limited extent fires or to support current forest firefighting techniques.” So—yes, the idea could hypothetically work in certain circumstances.
However, the authors do admit that the technology required for this approach to fighting fires is highly sophisticated, and that this could present issues for scaling and general availability.
But on the positive side, there are several ways that drone swarms could be used to simulate rain. They can simply drop water (or an extinguishing liquid), they can drizzle it, they can mist it—basically, they could be retrofitted to spread liquid in whatever way could be the most effective for the situation at hand.
With manned aircraft, on the other hand, you only have the option of dropping the water you’re carrying. And while manned aircraft can drop a whole lot more water at once than a single drone, much of that water doesn’t serve to fight the fire because it doesn’t actually wet as much surface area as it could if deployed in a different manner (i.e., as mist, or drizzled, etc.).
Right now the idea of using drone swarms to fight fires is just that—an idea.
But the paper lays out a good argument for the approach. And we know from experience that, in the drone industry, all it takes is a good idea to come up with a new use case for drones that might end up providing a cutting edge solution to a common problem, and saving lives in the process.
Think we’ll see drone swarms fighting the fires of the future? Share your thoughts in this thread on the UAV Coach community forum.