Aircraft

DEMON UAV achieves historic first 'flapless flight'

DEMON UAV achieves historic fi...
The DEMON UAV, that achieved flapless flight in Cumbria
The DEMON UAV, that achieved flapless flight in Cumbria
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The DEMON UAV, that achieved flapless flight in Cumbria
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The DEMON UAV, that achieved flapless flight in Cumbria
The air slots along the trailing edges of DEMON's wings
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The air slots along the trailing edges of DEMON's wings
The DEMON UAV, that achieved flapless flight in Cumbria
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The DEMON UAV, that achieved flapless flight in Cumbria
The DEMON UAV, that achieved flapless flight in Cumbria
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The DEMON UAV, that achieved flapless flight in Cumbria
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The DEMON UAV, that achieved flapless flight in Cumbria
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The DEMON UAV, that achieved flapless flight in Cumbria
The DEMON UAV, that achieved flapless flight in Cumbria
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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.

The DEMON UAV, that achieved flapless flight in Cumbria
The DEMON UAV, that achieved flapless flight in Cumbria

“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.

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9 comments
Skipjack
I would be worried about the holes for the jets of air freezing shut in cold environments.
PeetEngineer
This is a new development of an old technology, interesting though.
http://en.wikipedia.org/wiki/Blown_flap
ChoccyBoy
Freezing shut is easy to overcome - electrical heating is now used on propellers and leading edges together with windows on many types of aircraft. It does not take much energy to warm to just above freezing. Some parts also might, alternatively or in combination with electric heating, have a rubber jacket which is flexed using air pressure or electro mechanical devices to break and shake off any ice.
This is a great advance. Should also mean less weight in the craft and less fuel consumption, power required or more payload.
Gerfried Hans
Last time when flying I wondered about the gaps between flaps and wings introducing turbulence and thus drag. may be the first step would be to cover those gaps with fabric?
Crankie Fahrt
As with anything to do with bypass fan-jets, it would be simple to \"syphon-off\" some compressed air from each jet engine. Not only would this reduce hardware to create compressed air, as compression also tends to heat air up very quickly, taking care of any icing problems.
However, if the jet engines stop for whatever reason, the pilots would have absolutely NO control over the aircraft. None whatsoever.
So, that means that the compressed air must come from another source than the engines, and that just means more hardware and ducting to create, store and administer the compressed air to the appropriate outlets. I wonder if there would actually be any \"gain\". Hmmmmm.
Thomas Lewis
a little mix of hot jet exhaust should take care of any icing.
SimonClarke
I like the idea of a demonstration, I see it used as a back up system but the question always asked in aerospace design is, what happens if it stops working? in a conventional aircraft each aileron has two hydraulic systems, but even if one aileron stops working the other once will still provide some control.
Brian M
@Crankie Yes my thoughts as well, this seems to be taken something relatively simple and replacing it with something more complicated. The compressed air has to come from somewhere which I can only see as a higher risk than an ailerons and elevators.
Not sure I would refer to as flapless either, flaps are used for a different purpose!
Ralf Biernacki
Actually, a compressed air ducting system, with no moving parts other than valves and a compressor (and not even that, if engine compression is bled off instead) is much simpler, lighter, and more reliable than the traditional system with hydraulic lines, hydraulic pump, distributor valves, actuators, return lines, mechanical linkages, and moving flaps.