Drones are everywhere these days: from using them to take elaborate selfies to launching missiles at military targets, delivering aid to war-torn areas to imaging the deadly environment around lava lakes, they appear to be the multipurpose tool of the moment. Perhaps slightly strangely, then, the Defense Advanced Research Projects Agency (DARPA) wants drones to vanish into thin air. Specifically, they want drones that are biodegradable, able to fade away after completing their mission.
It’s not difficult to see why DARPA – the division of the U.S. Department of Defense tasked with developing cutting-edge technologies for the military – would want to build a vanishing drone. A drone that is on a mission the military do not wish to disclose at the time is always at a risk of being caught, whether it is delivering aid or a weapon delivery system to a specific area. The U.S. infamously lost a top-secret surveillance drone over Iranian airspace in 2011, proving deeply embarrassing for the Obama administration at the time. If, hypothetically, this drone could have dissolved in water or even in the air, this wouldn’t have been a problem.
This sci-fi-sounding concept builds off a pre-existing DARPA program, the Vanishing Programmable Resources (VAPR) initiative, which sought to develop electronic materials that were capable of physically disappearing when triggered remotely. Seeing as these drones are designed to fly up towards the sun before vanishing, DARPA has given the new program an appropriate name: ICARUS, an acronym for “Inbound, Controlled, Air-Releasable, Unrecoverable Systems.”
These drones are only designed to make one solo trip to their destination, leaving no evidence behind that they were ever there. For $8 million (£5.3 million), DARPA wants some very specific things: It must vanish within four hours of delivery, or within just 30 minutes during civil twilight. These little drones, at only 3 meters (10 feet) across, must fly 150 kilometers (93 miles) in a straight line.
DARPA appears to want the drones to “sublimate,” meaning that the solid drones will become a gas, bypassing the liquid phase. DARPA’s report highlights their definition of physical disappearance, or “transience,” as producing remnants no larger than 100 micrometers (roughly 1/1000th of an inch) in size. They note that this is as much of a technical challenge as it sounds: They are worried that it will be difficult to engineer such a drone that can perform a disappearing act so readily without inadvertently breaking up halfway through its mission.