The Department of Defense has released video of a test of swarming drones conducted in the skies over the US Navy's test range at Naval Air Weapons Station China Lake in California. In the October test, conducted by the Department of Defense Strategic Capabilities Office in collaboration with the Naval Air Systems Command, three FA-18 Hornet aircraft dispersed 104 Perdix micro-drones from onboard flare dispensers. The drones then communicated with each other, swarmed, and performed a series of designated "missions"—including finally swarming in a circle around a designated point on the ground.

The sound of the drone swarm, audible from the ground at the designated rendezvous point (at about 2 minutes into the video below), might be described as terrifying. But we'll leave that judgment to the reader. In the course of the test, the drones demonstrated advanced swarm behaviors, including self-healing communications, self-adapting formation flying, and collective decision-making.

The battery-powered Perdix drones were developed at MIT's Lincoln Labs and can be largely produced with a 3-D printer. "Due to the complex nature of combat, Perdix are not pre-programmed synchronized individuals, they are a collective organism, sharing one distributed brain for decision-making and adapting to each other like swarms in nature,” Strategic Capabilities Office Director William Roper explained in a statement about the test. “Because every Perdix communicates and collaborates with every other Perdix, the swarm has no leader and can gracefully adapt to drones entering or exiting the team.”

Perdix began as an MIT student project and was pulled into Lincoln Labs for defense modification, science modification, and testing back in 2013. Based entirely on commercial components used in smart phones and 3D-printable parts, Perdix is currently in its sixth generation of modifications. The October air-launch test confirmed that the current design could withstand the shock of being launched from the aircraft, buffeting at speeds of Mach 0.6, and the cold temperature of high altitude (-10 degrees Celsius).

The sort of autonomy demonstrated by Perdix has all sorts of implications going forward for military use of drones. Since no one operator can control all of the drones individually, drone swarms have to act on general instructions and determine how to carry them out collectively. While the prototype drones' orders were simply to "patrol" an area, they could conceivably be used for surveillance, battlefield communications networks, or even attacks—imagine a swarm of self-guiding flying hand grenades.