The Demon is an experimental

unmanned aerial vehicle An unmanned aerial vehicle (UAV), commonly known as a drone, is an aircraft without any human pilot, crew, or passengers on board. UAVs are a component of an unmanned aircraft system (UAS), which includes adding a ground-based controll ...

(UAV) developed and manufactured by British defence conglomerate BAE Systems. It has been referred to as being the world's first "

flap Flap may refer to: Arts, entertainment, and media * ''Flap'' (film), a 1970 American film * Flap, a boss character in the arcade game ''Gaiapolis'' * Flap, a minor character in the film '' Little Nemo: Adventures in Slumberland'' Biology and he ...

less" aircraft. The Demon was developed as a demonstrator for the ''flapless air vehicle integrated industrial research'' (FLAVIIR) programme. Developed from the conventional BAE Systems Eclipse UAV, it was used to trial an unconventional

aircraft flight control system A conventional fixed-wing aircraft flight control system consists of flight control surfaces, the respective cockpit controls, connecting linkages, and the necessary operating mechanisms to control an aircraft's direction in flight. Aircraft ...

over the course of two years. Various other technologies were also experimented with, including

modular Broadly speaking, modularity is the degree to which a system's components may be separated and recombined, often with the benefit of flexibility and variety in use. The concept of modularity is used primarily to reduce complexity by breaking a s ...

and cost-reduction techniques. On 17 September 2010, the Demon conducted its first flight without using any conventional flight control surfaces. It has been speculated that the technology has potential applications in both civilian and military aviation.

Development

During the early 21st century, British defence conglomerate BAE Systems initiated a five-year research programme known as ''flapless air vehicle integrated industrial research (FLAVIIR)''. This effort had a declared budget of £6.5 million, which was financed by both BAE Systems and the UK's Engineering and Physical Sciences Research Council. It had the aim of developing and testing a new

aerodynamic Aerodynamics, from grc, ἀήρ ''aero'' (air) + grc, δυναμική (dynamics), is the study of the motion of air, particularly when affected by a solid object, such as an airplane wing. It involves topics covered in the field of fluid dyn ...

circulation-based

, manipulating airflow via non-traditional means; unlike most prior efforts, it sought to bring technologies together to form a functional system rather than develop isolated elements. Participants in the programme included various British aeronautics companies, specialists, and academic institutions included Cranfield University and nine other British universities."Developing the next generation of Unmanned Aerial Vehicles (UAVs) with BAE Systems."
''Cranfield University'', Retrieved: 6 July 2019."Flaviir project trials new forms of wing command."
''The Engineer'', 11 July 2010. During August 2007, an American patent was filed for elements of this new control system concept; it was granted during July 2011. As development proceeded, it was decided that producing an experimental unmanned air vehicle to demonstrate manoeuvring without the aid of conventional

flight control surfaces Aircraft flight control surfaces are aerodynamic devices allowing a pilot to adjust and control the aircraft's flight attitude. Development of an effective set of flight control surfaces was a critical advance in the development of aircraft. Ea ...

. The conventional BAE Systems Eclipse was selected as the basis for the demonstrator. Ahead of the flight test programme, it was subjected to various ground-based tests, including the use of

wind tunnel Wind tunnels are large tubes with air blowing through them which are used to replicate the interaction between air and an object flying through the air or moving along the ground. Researchers use wind tunnels to learn more about how an aircraft ...

s and scale models.Coppinger, Rob
"Ground trials start for UK vectored thrust prototype UAV."
''Flight International'', 2 October 2009. The Demon participated in a two-year demonstration programme, during which the team studied the UAV's performance throughout its flight envelope. On 17 September 2010, the Demon performed its first flight in which all of its conventional control surfaces were deactivated during a portion of the flight off the coast of

Cumbria Cumbria ( ) is a ceremonial and non-metropolitan county in North West England, bordering Scotland. The county and Cumbria County Council, its local government, came into existence in 1974 after the passage of the Local Government Act 1972. C ...

, having flown out of

Barrow/Walney Island Airport Barrow/Walney Island Airport (formerly RAF Walney Island) is located on Walney Island, northwest of the centre of Barrow-in-Furness, Cumbria, England. The airport is owned by BAE Systems, who operate private communication flights to location ...

."BAE’s flapless UAV is breath of fresh air."
''

Institution of Mechanical Engineers The Institution of Mechanical Engineers (IMechE) is an independent professional association and learned society headquartered in London, United Kingdom, that represents mechanical engineers and the engineering profession. With over 120,000 member ...

'', 6 October 2010."Showcase UAV demonstrates 'Flapless Flight'."
''phys.org'', 27 September 2010. Richard Williams, BAE's programme director for future capability, stated of the occasion: "I feel sure I have witnessed a significant moment in aviation history". In late 2010, BAE Systems stated that the Demon shall not be followed up by a direct production aircraft, but its technologies would be filtered through to other platforms instead.Ford, Jason
"MAGMA jet-powered UAV sets course for flapless flight."
''The Engineer'', 14 December 2017. Aerospace periodical

Flight International ''Flight International'' is a monthly magazine focused on aerospace. Published in the United Kingdom and founded in 1909 as "A Journal devoted to the Interests, Practice, and Progress of Aerial Locomotion and Transport", it is the world's old ...

speculated that this unique circulation control system could one day be employed in civilian aviation to reduce the size of the wing on widebody

airliners An airliner is a type of aircraft for transporting passengers and air cargo. Such aircraft are most often operated by airlines. Although the definition of an airliner can vary from country to country, an airliner is typically defined as an ai ...

. Its developers have stated their hopes that the new technology could be used to reduce noise, cut fuel consumption, and lower maintenance costs. In terms of military applications, the technology might enable future combat aircraft to achieve greater levels of stealth than conventionally equipped counterparts.

Design

The BAE Systems Demon is an experimental

(UAV). In terms of its basic configuration, it is a blended wing-body aircraft, possessing an approximate wingspan of 8-foot (2.5m) and a weight of 200 lb (90 kg). In flight, it could attain a maximum speed of 150 kn. It was outfitted with a conventional

-based flight control system which can be switched on and off during flight, allowing the aircraft to alternate between its experimental and conventional control system. The Demon was built to flight test a novel aerodynamic control system. This system uses a combination of engine

exhaust gas Exhaust gas or flue gas is emitted as a result of the combustion of fuels such as natural gas, gasoline (petrol), diesel fuel, fuel oil, biodiesel blends, or coal. According to the type of engine, it is discharged into the atmosphere through an ...

, which is redirected using a

thrust vectoring Thrust vectoring, also known as thrust vector control (TVC), is the ability of an aircraft, rocket, or other vehicle to manipulate the direction of the thrust from its engine(s) or motor(s) to control the attitude or angular velocity of the ve ...

nozzle, and

bleed air Bleed air is compressed air taken from the compressor stage of a gas turbine upstream of its fuel-burning sections. Automatic air supply and cabin pressure controller (ASCPCs) valves bleed air from high or low stage engine compressor sections. Lo ...

, which is precisely controlled to provide control over the same aerodynamic forces that would be traditionally provided by numerous

, including flaps, ailerons and

elevators An elevator or lift is a cable-assisted, hydraulic cylinder-assisted, or roller-track assisted machine that vertically transports people or freight between floors, levels, or decks of a building, vessel, or other structure. They are ...

. Referred to as "fluidic flight controls", the arrangement used on the Demon reportedly functioned by directing air from a rectangular exhaust nozzle over upper and lower surfaces, using the Coandă effect to establish control over pitch."DEMON UAV – Flying Without Flaps."
'' BAE Systems'', Retrieved: 6 July 2019. For

roll Roll or Rolls may refer to: Movement about the longitudinal axis * Roll angle (or roll rotation), one of the 3 angular degrees of freedom of any stiff body (for example a vehicle), describing motion about the longitudinal axis ** Roll (aviation) ...

control,

is blown over a Coanda surface installed on the

trailing edge The trailing edge of an aerodynamic surface such as a wing is its rear edge, where the airflow separated by the leading edge meets.Crane, Dale: ''Dictionary of Aeronautical Terms, third edition'', page 521. Aviation Supplies & Academics, 199 ...

of the wing. By controlling

boundary layer In physics and fluid mechanics, a boundary layer is the thin layer of fluid in the immediate vicinity of a bounding surface formed by the fluid flowing along the surface. The fluid's interaction with the wall induces a no-slip boundary cond ...

conditions, the fluidic controls can also generate either greater

lift Lift or LIFT may refer to: Physical devices * Elevator, or lift, a device used for raising and lowering people or goods ** Paternoster lift, a type of lift using a continuous chain of cars which do not stop ** Patient lift, or Hoyer lift, mobil ...

or drag during the take-off and landing phases of flight. Beyond the novel flight control system, the Demon was used to trial various other technologies, such as the manufacture and assembly of a fully bonded structure. This structure possessed low cost material reinforcing features, which reportedly achieved roughly 50% cost savings over the use of conventional manufacturing processes. A key goal of the demonstrator was to trial cheaper, more

UAV technology, exploring designs have been generated through cross-disciplinary interactions.

References

External links

BAE FLAVIIR project

Engineering and Physical Sciences Research Council (EPSRC) Casestudy

Ground video of the Demon's first flight
{{BAE aircraft British Aerospace aircraft 2010s British experimental aircraft Unmanned military aircraft of the United Kingdom

Development

Design

See also

References

External links