An unmanned aerial vehicle named DEMON made history last month when it demonstrated “flapless flight” at an airfield in Cumbria, England. The demonstrator aircraft’s ailerons/elevators were locked off, allowing it to maneuver using nothing but a series of forced-air jets along the trailing edges of its wings. In the future, such technology could be applied to military or commercial aircraft.
DEMON was developed by aerospace company BAE Systems, Cranfield University, and nine other UK universities. It is part of BAE’s £6.2 million (US$9.85 million) FLAVIIR (Flapless Air Vehicle Integrated Industrial Research) program, and took five years to complete.
Its “fluidic flight control” system consists of an auxiliary power unit that supplies compressed air to a series of circulation control devices, located in the wings. These release the compressed air from slots along the top and bottom trailing edges of both wings, creating a “blade of air” immediately behind them. Using flight control algorithms to vary which slots the air comes out of (top or bottom, left or right), the roll direction of the plane can be determined.
“What the FLAVIIR Team have achieved in such a short time is nothing short of remarkable,” said BAE’s Richard Williams. “I was in Cumbria to watch DEMON fly and I feel sure I have witnessed a significant moment in aviation history.”
Flapless aircraft would have several advantages over traditional planes, in that they would have fewer moving parts, require less maintenance and present a stealthier profile.