A flaperon (a

portmanteau A portmanteau word, or portmanteau (, ) is a blend of wordsflap 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 ...

and

aileron An aileron (French for "little wing" or "fin") is a hinged flight control surface usually forming part of the trailing edge of each wing of a fixed-wing aircraft. Ailerons are used in pairs to control the aircraft in roll (or movement around ...

) on an aircraft's wing is a type of control surface that combines the functions of both flaps and ailerons. Some smaller

kitplane Homebuilt aircraft, also known as amateur-built aircraft or kit planes, are constructed by persons for whom this is not a professional activity. These aircraft may be constructed from "scratch", from plans, or from assembly kits.Armstrong, Kenn ...

s have flaperons for reasons of simplicity of manufacture, while some large commercial aircraft such as the

Boeing 747 The Boeing 747 is a large, long-range wide-body airliner designed and manufactured by Boeing Commercial Airplanes in the United States between 1968 and 2022. After introducing the 707 in October 1958, Pan Am wanted a jet times its size, t ...

, 767,

777 777 may refer to: * 777 (number), a number * AD 777, a year of the Julian calendar * 777 BC, a year in the 8th century BC * Boeing 777, a commercial jet airliner :* Boeing 777X, the newer generation of the Boeing 777. Art and entertainment Alb ...

, and

787 787 may refer to: * Boeing 787 Dreamliner, a jet airliner * AD 787, a year * 787 BC, a year * Mazda 787/787B, a Japanese rotary-engine race car which won the 1991 Le Mans Race * Porsche 787, a race car from the 1960s * 787 series, a train model o ...

may have a flaperon between the flaps and aileron. The 787 has a configuration known as a SpoileFlaperon that combines the action of spoilers, flaps and ailerons into one control surface.

Operation

In addition to controlling the

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), ...

or bank of an aircraft, as do conventional ailerons, both flaperons can be lowered together to reduce stall speed, similarly to a set of flaps. On a plane with flaperons, the pilot still has the standard separate controls for ailerons and flaps, but the flap control also varies the flaperon's range of movement. A mechanical device called a "mixer" is used to combine the pilot's input into the flaperons. While the use of flaperons rather than ailerons and flaps might seem to be a simplification, some complexity remains through the intricacies of the mixer. Some aircraft, such as the

Denney Kitfox The Denney Kitfox is a series of small side-by-side, two-seat, high-wing, single engine kit aircraft, designed and originally manufactured by Dan Denney and his company Denney Aerocraft of Boise, Idaho. The aircraft is amateur-built and ...

, suspend the flaperons below the wing (rather in the manner of slotted flaps) to provide undisturbed airflow at high angles of attack or low airspeeds. When the flaperon surface is hinged below the trailing edge of a wing, they are sometimes named "Junker Flaperons", from the ''doppelflügel'' (lit., "double wing") type of trailing edge surfaces used on a number of

Junkers Junkers Flugzeug- und Motorenwerke AG (JFM, earlier JCO or JKO in World War I, English: Junkers Aircraft and Motor Works) more commonly Junkers , was a major German aircraft and aircraft engine manufacturer. It was founded there in Dessau, Germ ...

aircraft of the 1930s, such as the

Junkers Ju 52 The Junkers Ju 52/3m (nicknamed ''Tante Ju'' ("Aunt Ju") and ''Iron Annie'') is a transport aircraft that was designed and manufactured by German aviation company Junkers. Development of the Ju 52 commenced during 1930, headed by German Aeros ...

airliner, and the iconic

Junkers Ju 87 The Junkers Ju 87 or Stuka (from ''Sturzkampfflugzeug'', "dive bomber") was a German dive bomber and ground-attack aircraft. Designed by Hermann Pohlmann, it first flew in 1935. The Ju 87 made its combat debut in 1937 with the Luftwaffe's Con ...

''Stuka'' World War II

dive bomber A dive bomber is a bomber aircraft that dives directly at its targets in order to provide greater accuracy for the bomb it drops. Diving towards the target simplifies the bomb's trajectory and allows the pilot to keep visual contact througho ...

Research

Current research seeks to coordinate the functions of aircraft flight control surfaces (ailerons,

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 ...

elevon Elevons or tailerons are aircraft control surfaces that combine the functions of the elevator (used for pitch control) and the aileron (used for roll control), hence the name. They are frequently used on tailless aircraft such as flying wings. ...

s, flaps, and flaperons) so as to reduce weight, cost, drag,

inertia Inertia is the idea that an object will continue its current motion until some force causes its speed or direction to change. The term is properly understood as shorthand for "the principle of inertia" as described by Newton in his first law ...

, and thereby achieve improved control response, reduced complexity, and reduced radar visibility for stealth purposes. Beneficiaries of such research might include drones (UAVs) and the latest

fighter aircraft Fighter aircraft are fixed-wing military aircraft designed primarily for air-to-air combat. In military conflict, the role of fighter aircraft is to establish air superiority of the battlespace. Domination of the airspace above a battlefield ...

. These research approaches include flexible wings and fluidics:

Flexible wings

In flexible wings, much or all of a wing surface can change shape in flight to deflect air flow. The

X-53 Active Aeroelastic Wing The X-53 Active Aeroelastic Wing (AAW) development program is a completed American research project that was undertaken jointly by the Air Force Research Laboratory (AFRL), Boeing Phantom Works and NASA's Dryden Flight Research Center, where t ...

is a

NASA The National Aeronautics and Space Administration (NASA ) is an independent agency of the US federal government responsible for the civil space program, aeronautics research, and space research. NASA was established in 1958, succeeding t ...

effort. The

Adaptive Compliant Wing An adaptive compliant wing is a wing which is flexible enough for aspects of its shape to be changed in flight. Flexible wings have a number of benefits. Conventional flight control mechanisms operate using hinges, resulting in disruptions to the ...

is a military and commercial effort. This may be seen as a return to the

wing warping Wing warping was an early system for lateral (roll) control of a fixed-wing aircraft. The technique, used and patented by the Wright brothers, consisted of a system of pulleys and cables to twist the trailing edges of the wings in opposite direc ...

used and

patented A patent is a type of intellectual property that gives its owner the legal right to exclude others from making, using, or selling an invention for a limited period of time in exchange for publishing an enabling disclosure of the invention."A p ...

by the Wright brothers.

Fluidics

fluidics Fluidics, or fluidic logic, is the use of a fluid to perform analog or digital operations similar to those performed with electronics. The physical basis of fluidics is pneumatics and hydraulics, based on the theoretical foundation of fluid dyna ...

, forces in vehicles occur via circulation control, in which larger, more complex mechanical parts are replaced by smaller simpler fluidic systems (slots which emit air flows), where larger forces in fluids are diverted by smaller jets or flows of fluid intermittently, to change the direction of vehicles. In this use, fluidics promises lower mass, costs (up to 50% less), and very low

and response times, as well as simplicity.

References

{{Aircraft components Aircraft controls Aircraft wing design

Operation

Research

Flexible wings

Fluidics

See also

References