Flight is a fiddly affair filled with flaps. While early human attempts to create flying machines that generated thrust and steering by flapping didn’t pan out, fixed-wing flight is still very much a field of flaps, of raised and lowered surfaces for directional control.

Working with researchers at The University of Manchester, engineers from British defense giant BAE successfully flew a flapless flier over the skies of northwest Wales. Dubbed “MAGMA,” the drone tested two technologies with implications for stealthy flight and cheaper maintenance.

How does the drone steer without flaps? Well, it blows.

More specifically, the MAGMA drone relies on two techniques. The first is “wing circulation control,” where air taken from the plane’s engine is blown supersonically through narrow slots “around a specially shaped wing tailing edge in order to control the aircraft,” and the second is “fluidic thrust vectoring,” which controls the aircraft by “blowing air jets inside the nozzle to deflect the exhaust jet and generate a control force.”

The cumulative effect is that, instead of angling physical flaps to direct how outside air flows around the plane, flows of air through the vehicle can be shaped to provide steering, thanks to careful distribution through the craft and the introduction of other, injected air to disperse the flow. With no injected air, the drone flies with its nose angled down. With some injected air, it flies parallel to the ground, and with a lot of injected air, the drone flies nose angled up. That likely accounts for pitch, with the wing circulation accounting for yaw.

Wedge-shaped and V-tailed, the MAGMA isn’t the first time BAE demonstrated flapless flight in a drone. In 2010, BAE used thrust vectoring with the DEMON UAV to show that such steering could be done. MAGMA, too, has been in the works for some time, with earlier flights in 2017. In the meantime, BAE has been able to use 3D printed titanium parts, refining the technology to demonstrate what is possible now and what might come in the future.

Without flaps, drones would have an increased stealth profile, though the extent of that stealth improvement may be limited by the persistence of prominent tails. BAE’s existing stealth combat drone demonstrator, the Taranis, is similarly wedge shaped by a true flying wing, no tails included. As such, the technology demonstrated here should be seen as a possible inclusion for future stealth, rather than an inevitability.

Watch the MAGMA fly below: