Flying drone deploys ping pong firebombs for toastier temperatures
It may seem like a case of competing interests, but the team at the University of Nebraska developing a more potent fire-distribution robot really is looking to prevent fires as much as start them. The proposed flying drone would be used to start prescribed burns, which are intended to remove fuel from an environment, hopefully preventing a bigger blaze down the line that could threaten lives or property. Prescribed burns aren’t new, but the degree of accuracy and potency that this new drone may offer would be an important innovation, and that’s even before one considers the cool factor of what’s essentially a remote controlled dragon.
Dropping fireballs without the danger
The dryly-named Unmanned Aerial System for Fire Fighting (UAS-FF) is based on the quadcopter chassis of many commercial drones. On top, the drone carries a tube-fed hopper, with a payload of potassium permanganate-filled ping pong balls. On command, those balls are given an injection of liquid glycol, then dropped at a precise location. The two ingredients mix for a moment or two as a chemical reaction builds inside the “dragon egg,” eventually bursting into flame to ignite the surrounding foliage.
As much as a fire-starting robot doesn’t sound like the safest idea, safety is actually one of the big reasons to develop this project. Prescribed burns today are often set by hand, or from the air, although flying over heat and gusts of wind can be difficult and dangerous for helicopter pilots. What’s more, one of the goals of Dirac Twidwell is to try to light hotter fires with these drones, and so keeping humans a safe distance away is a critical consideration.
Incentives for stronger incendiaries
The desire for heat isn’t just to up the wow-factor inherent in the UAS-FF. “Extreme fires,” as they’re known, may actually be a better match for the natural conditions that firefighters try to recreate to a degree when starting prescribed burns. Many plants, particularly grassy plains, have evolved around the concept of regular fires renewing the ecosystem. These fires are most likely sparked by lightning strikes in hot, dry weather, and can rip through landscapes, removing old growth and saturating the ground with nutrients. Quick growing plants like grasses adapted to meet these cycles, taking advantage of these conditions in a way that woodier trees do not. However, since controlled burns are most often done in cooler, wetter conditions to help keep them under control, the flames don’t ever reach the extremes of a natural summer grass fire.
The UAS-FF should get us closer to the “real” thing. Being able to start fires with precise perimeters that can safely grow to higher temperatures would better eliminate plants that are unnaturally creeping into prairie ecosystems, like juniper. The drone is still pending regulatory approval before it can really go to work, as the Federal Aviation Administration generally frowns upon lighting dangerously hot fires from the sky, even if it’s the safest way to do it.
Source: Restoring prairie and fighting wildfire with (drone launched) fire(balls), Scienmag
