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Boeing 777 flaperon.
Flaperons on a Kitfox Model 3, built in 1991.
Flaperons (Junkers style) on an ICP Savannah Model S, built in 2010.

A flaperon is a type of aircraft control surface that combines aspects of both flaps and ailerons.[citation needed]


In addition to controlling the roll or bank of an aircraft, as do conventional ailerons, both flaperons can be lowered together to function similarly to a dedicated set of flaps. Both ailerons could also be raised, which would give spoilerons.[citation needed]

The pilot has separate controls for ailerons and flaps. A mixer is used to combine the separate pilot input into this single set of control surfaces called flaperons. The use of flaperons instead of separate ailerons and flaps can reduce the weight of an aircraft. The complexity is transferred from having a double set of control surfaces (flaps and ailerons) to the mixer.[citation needed][clarification needed]

Many designs that incorporate flaperons mount the control surfaces away from the wing to provide undisturbed airflow at high angles of attack or low airspeeds.[citation needed]

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 aircraft of the 1930s, such as the Junkers Ju 52 airliner, and Junkers Ju 87 Stuka iconic World War II dive bomber.[citation needed]

A single flaperon discovered on Reunion Island is the sole piece of debris found to date from the missing Boeing 777 that was involved in Malaysian Airlines Flight MH370.


Several technology research and development efforts exist to integrate the functions of aircraft flight control systems such as ailerons, elevators, elevons, flaps, and flaperons into wings to perform the aerodynamic purpose of reducing factors such as mass, cost, drag, inertia (for faster, stronger control response), complexity (mechanically simpler, fewer moving parts or surfaces, less maintenance), and radar cross section for stealth. Expected uses would be for many unmanned aerial vehicles (UAVs) as well as 6th generation fighter aircraft. Two promising approaches are: flexible wings; and fluidics.[citation needed]

Flexible wings[edit]

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 is a NASA effort. The Adaptive Compliant Wing is a military and commercial effort.[1][2][3]


In fluidics, 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.[4][5][6] In this use, fluidics promises lower mass, costs (up to 50% less), and very low inertia and response times, as well as simplicity.[citation needed]

See also[edit]


  1. ^ Scott, William B. (27 November 2006), "Morphing Wings", Aviation Week & Space Technology 
  2. ^ "FlexSys Inc.: Aerospace". Retrieved 2011-04-26. 
  3. ^ Kota, Sridhar; Osborn, Russell; Ervin, Gregory; Maric, Dragan; Flick, Peter; Paul, Donald. "Mission Adaptive Compliant Wing – Design, Fabrication and Flight Test" (PDF). Ann Arbor, MI; Dayton, OH, U.S.A.: FlexSys Inc., Air Force Research Laboratory. Retrieved 2011-04-26. 
  4. ^ P John (2010). "The flapless air vehicle integrated industrial research (FLAVIIR) programme in aeronautical engineering". Proceedings of the Institution of Mechanical Engineers, Part G: Journal of Aerospace Engineering (London: Mechanical Engineering Publications) 224 (4): 355–363. doi:10.1243/09544100JAERO580. ISSN 0954-4100. 
  5. ^ "Showcase UAV Demonstrates Flapless Flight". BAE Systems. 2010. Retrieved 2010-12-22. 
  6. ^ "Demon UAV jets into history by flying without flaps". Metro.co.uk (London: Associated Newspapers Limited). 28 September 2010.