BAE Systems has released an unmanned aerial vehicle (UAV) that uses the Coanda effect to maneuver the aircraft in place of control surfaces such as ailerons and flaps. The Coanda effect is the tendency of a fluid jet to be attracted to a near by solid surface. It has many applications in air conditioning and cardiovasular medicine apart from aeronautical and even space applications. In airplanes, directed air flows use the Coanda effect to cause the air to stick to the control surfaces such as ailerons and elevators to provide lift for attitude control.
BAE’s Advanced Technology Center, along with Manchester University and 9 other UK universities, with support from the Engineering and Physical Sciences Research Council (EPSRC) embarked on the Project FLAVIIR (Flapless, autonomous vehicle, integrated industry research) in 2004. They aim to bring together a range of technologies, including aerodynamics, control systems, electromagnetics, manufacturing, materials/Structures, numerical simulation and integration, “to develop technologies for a maintenance free, low cost UAV without conventional control surfaces and without performance penalty over conventional craft.”
Their first version is called the Demon UAV, which is a delta-winged, “blended wing body” aircraft configuration. The Coanda effect is utilized by blowing jets of air over specifically designed geometries strategically placed over the wing to provide lift as needed for the maneuvers. The “flapless system” would require less maintenance and would produce less noise, giving the aircraft tremendous stealth capabilities. The fluidic flight control system could also allow for planes with significantly reduced wing size.
A video of the Demon UAV in flight is seen here on Youtube.
Here is a link to an article at Popular Science.
I am not sure if the TARANIS also has similar technologies. I do not see any control surfaces on the wings, but two pairs of orifices are visible towards the rear end on the top surface of the wings on either side of the fuselage.