A flaperon is a type of aircraft control surface that combines aspects of both flaps

Flap (aircraft)

Flaps are normally hinged surfaces mounted on the trailing edges of the wings of a fixed-wing aircraft to reduce the speed an aircraft can be safely flown at and to increase the angle of descent for landing without increasing air speed. They shorten takeoff and landing distances as well as...

 and aileron

Aileron

Ailerons are hinged flight control surfaces attached to the trailing edge of the wing of a fixed-wing aircraft. The ailerons are used to control the aircraft in roll, which results in a change in heading due to the tilting of the lift vector...

s. In addition to controlling the roll

Flight controls

Aircraft flight control surfaces allow a pilot to adjust and control the aircraft's flight attitude.Development of an effective set of flight controls was a critical advance in the development of aircraft...

 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 spoileron

Spoileron

In aeronautics spoilerons are flight control surfaces, specifically spoilers that can be used asymmetrically to achieve the effect of ailerons, i.e. to roll an aircraft by reducing the lift of one wing but unlike ailerons not increasing the lift of the other wing...

s.

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.

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.

When the flaperon surface is hinged below the trailing edge of a wing, they are sometimes named "Junker Flaperons", from the doppelflügel type of trailing edge surfaces used on a number of Junkers

Junkers

Junkers Flugzeug- und Motorenwerke AG , more commonly Junkers, was a major German aircraft manufacturer. It produced some of the world's most innovative and best-known airplanes over the course of its fifty-plus year history in Dessau, Germany. It was founded there in 1895 by Hugo Junkers,...

 aircraft of the 1930s, such as the Junkers Ju 52

Junkers Ju 52

The Junkers Ju 52 was a German transport aircraft manufactured from 1932 to 1945. It saw both civilian and military service during the 1930s and 1940s. In a civilian role, it flew with over 12 air carriers including Swissair and Deutsche Luft Hansa as an airliner and freight hauler...

 airliner, and Junkers Ju 87

Junkers Ju 87

The Junkers Ju 87 or Stuka was a two-man German ground-attack aircraft...

 Stuka iconic World War II dive bomber

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 reduces the distance the bomb has to fall, which is the primary factor in determining the accuracy of the drop...

.

Notable experimental aircraft using flaperons include the V-22 Osprey

V-22 Osprey

The Bell Boeing V-22 Osprey is an American multi-mission, military, tiltrotor aircraft with both a vertical takeoff and landing , and short takeoff and landing capability...

, the Zenith STOL CH 701, the Kitfox, the ICP Savannah

ICP Savannah

The ICP Savannah is a high wing, single engine, ultralight with side-by-side seating for two produced in Italy. It has sold in large numbers, particularly in Europe. The Savannah is in production, in both kit and ready to fly form.-Design and development:...

 and the IBIS

Research

Several technology research and development efforts exist to integrate the functions of aircraft flight control systems such as ailerons, elevators

Elevator (aircraft)

Elevators are flight control surfaces, usually at the rear of an aircraft, which control the aircraft's orientation by changing the pitch of the aircraft, and so also the angle of attack of the wing. In simplified terms, they make the aircraft nose-up or nose-down...

, elevon

Elevon

Elevons are aircraft control surfaces that combine the functions of the elevator and the aileron , hence the name. They are frequently used on tailless aircraft such as flying wings. An elevon that is not part of the main wing, but instead is a separate tail surface, is a stabilator...

s, flaps and flaperons into wings to perform the aerodynamic purpose with the advantages of less: mass, cost, drag, inertia

Inertia

Inertia is the resistance of any physical object to a change in its state of motion or rest, or the tendency of an object to resist any change in its motion. It is proportional to an object's mass. The principle of inertia is one of the fundamental principles of classical physics which are used to...

 (for faster, stronger control response), complexity (mechanically simpler, fewer moving parts or surfaces, less maintenance), and radar cross section

Radar cross section

Radar cross section is a measure of how detectable an object is with a radar. A larger RCS indicates that an object is more easily detected.An object reflects a limited amount of radar energy...

 for stealth

Stealth technology

Stealth technology also termed LO technology is a sub-discipline of military tactics and passive electronic countermeasures, which cover a range of techniques used with personnel, aircraft, ships, submarines, and missiles, to make them less visible to radar, infrared, sonar and other detection...

. These may be used in many unmanned aerial vehicle

Unmanned aerial vehicle

An unmanned aerial vehicle , also known as a unmanned aircraft system , remotely piloted aircraft or unmanned aircraft, is a machine which functions either by the remote control of a navigator or pilot or autonomously, that is, as a self-directing entity...

s (UAVs) and 6th generation fighter aircraft

Fighter aircraft

A fighter aircraft is a military aircraft designed primarily for air-to-air combat with other aircraft, as opposed to a bomber, which is designed primarily to attack ground targets...

. Two promising approaches are flexible wings, and fluidics.

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

NASA

The National Aeronautics and Space Administration is the agency of the United States government that is responsible for the nation's civilian space program and for aeronautics and aerospace research...

 effort. The Adaptive Compliant Wing

Adaptive Compliant Wing

The Adaptive Compliant Wing is a wing design developed by FlexSys, Inc., which is flexible so that aspects of its shape can be changed in flight....

 is a military and commercial effort.

In 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 dynamics...

, 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 inertia

Inertia

Inertia is the resistance of any physical object to a change in its state of motion or rest, or the tendency of an object to resist any change in its motion. It is proportional to an object's mass. The principle of inertia is one of the fundamental principles of classical physics which are used to...

and response times, and simplicity.