With their tiny propellers buzzing, the fleet of Chinese aircraft, little larger than model planes, are flung into the air one at a time by huge rubber bands. Soon the sky is full of toylike drones flying in formations over unidentified mountains in China.

This unlikely spectacle could represent a revolution in military affairs. The June 11 demonstration of “swarm” technology by China Electronics Technology Group, a state-owned high-tech company, included 119 drones. That made it the world’s largest-ever swarm, according to CETC, breaking a US-held record.

Each tiny aircraft — bought online for a few hundred dollars — is loaded with software and sensors capable of communicating with the other drones in the swarm. Developers are working towards a future where thousands could operate in sync, identifying and attacking targets. In theory, such swarms could feature drones fitted with missiles or warheads capable of sophisticated attacks designed to overwhelm defences with their sheer numbers.