In 2021, as US defence contractors sketched concepts for a futuristic drone controlled by blasts of air instead of mechanical flaps, China quietly flew one.
Now, newly published research has revealed for the first time details of how Beijing outpaced Washington in this pivotal arms race.
Next-generation air dominance hinges on eliminating traditional control surfaces. Rudders, flaps and tail fins create radar reflections and thermal signatures.
Assist or even replace them with fluidic systems – steering jets via precise air pulses – and you gain more invisibility, fuel efficiency and even underwater manoeuvrability.
The Pentagon recognised this early on, but it was not until 2023 that the Defence Advanced Research Projects Agency (DARPA) greenlit the X-65 programme, a radical drone designed to validate fluidic flight control, also known as CRANE (Control of Revolutionary Aircraft with Novel Effectors).
The legendary US agency, birthplace of stealth jets and GPS, has always been a leader in futuristic tech.
But according to a paper by Professor Luo Zhenbing with China’s National University of Defence Technology (NUDT), published last month in Acta Aeronautica et Astronautica Sinica, America’s “revolutionary” project is already years behind China’s operational systems.
China’s technology outperforms what DARPA is still prototyping – and with far broader applications, according to Luo and his colleagues.
At the heart of China’s breakthrough is what Luo calls “dual synthetic jet” (DSJ) technology, which can generate a whoosh of air by vibrating ceramic plates in wing-mounted compartments.
Unlike standard US designs – which use single air chambers prone to breakdown – China’s DSJ units pair two chambers that fire pulses alternately, cancelling stress on parts.
This dual-chamber trick solves a critical flaw: pressure damage during dives or underwater use. NUDT tests show DSJ units last three times longer than US equivalents while using half the energy.
By tweaking pulse timing, engineers can now steer drones at will mid-flight with air jets “pushing” the plane left or right, up or down.
Meanwhile the jets can prevent ice build-up by blowing supercooled droplets off the wings.
But one of the most impressive applications occurs in engine thrust vectoring.
A three-flow nozzle design, first tested in 2023, showed that a drone can change course freely and swiftly with a vector engine that has no moving parts in its exhaust nozzle – a revolutionary design that has not been revealed to the world until now.
DSJ-enabled thrusters also allow a submersible drone to switch seamlessly from underwater “swimming” to aerial flight, a first for active flow systems, according to the researchers.
China’s first DSJ-controlled drones took flight in 2021. A fixed-wing UAV equipped with DSJ circulation control actuators on its wing tips demonstrated roll rates of 15.62 degrees per second without traditional control surfaces.
By 2023, NUDT engineers expanded the system to a flying-wing drone, mastering pitch, yaw and roll via fluidic thrust vectoring and reverse jet streams. Trials showed that maximum roll and yaw control rate outperformed mechanical counterparts in responsiveness.
“It is the result of more than two decades of hard work,” Luo and his colleagues said in the paper.
In 2024, Beijing established the Flow Control and Thermal Management Committee under its Aeronautical Society, marshalling academia and state-owned giants like the Aviation Industry Corporation of China (AVIC) to accelerate the application of the new technology.
DARPA’s X-65, by contrast, remains grounded, according to openly available information.
The big-tail drone – originally designed to validate fluidic controls for the US Air Force’s secretive Next-Generation Air Dominance (NGAD) fighter – is expected to make its first flight later this year.
