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The term canard has also come to mean the tail surface itself, when mounted in that configuration.

In colloquial French canard also means hoax, and that meaning occurs occasionally in English, too. In the field of computing, it has also acquired the meaning of "confused and mistaken belief".

1 Canard aircraft characteristics

1.1 Advantages

The canard surface normally produces positive (upwards) lift which adds to the overall lift, whereas a conventional tailplane normally produces a downforce, partially cancelling the lift from the main wings.

Careful design of a canard aircraft can make it effectively "stall-proof" - the canard surface stalls first which tends to pitch the nose down and prevent the main wing from stalling.

Canard designs can sometimes have a more useful range of centre of gravity.

1.2 Disadvantages

The wing operates in the downwash from the canard surface, which reduces its efficiency.

It is often difficult to apply flaps to the wing in a canard design. Deploying flaps causes a large nose-down pitching moment, but in a conventional aeroplane this effect is considerably reduced by the increased downwash on the tailplane which produces a restoring nose-up pitching moment. With a canard design there is no tailplane to alleviate this effect. The Beech Starship attempted to overcome this problem with a swing-wing canard surface which swept forwards to counteract the effect of deploying flaps, but many canard designs have no flaps at all.

In order to achieve longitudinal stability, most canard designs feature a small canard surface operating at a high lift coefficientThe coefficient of lift is a number associated with a particular shape of an aerofoil, and is incorporated in the lift equation to predict the lift force generated by a wing using this particular cross section. Note that the lift equation does not include (C_L), while the main wing, although much larger, operates at a much smaller C_L and never achieves its full lift potential.

2 Examples of canard aircraft

Aircraft that have successfully employed this configuration include:

• Wright Flyer
• Santos-Dumont 14-bis
• IAI KfirThe IAI Kfir is an Israeli-built military aircraft based on the French Mirage 5. Following a French government embargo that prevented Dassault selling Israel the Mirages that they had already paid for, IAI produced an unlicenced copy of this aircraft as t
• Saab ViggenThe Saab Viggen Thunderbolt ) or Saab 37 is a Swedish fighter aircraft manufactured between 1970 and 1990 to replace the Saab Draken. The first studies aimed at developing a successor to the Draken were carried out between 1952 and 1957. Construction star
• Eurofighter TyphoonThe Eurofighter Typhoon is a twin- engine multi-role canard- delta fighter aircraft, very similar to the US- German Rockwell-MBB X-31 prototype and designed and built by a consortium of European nations formed in 1983. History The initial members were the
• Saab GripenThe Saab JAS-39 "Gripen Griffin is a fighter aircraft, originally from Sweden but later also United Kingdom, manufactured by Saab and BAE Systems. The fighters are sold by the Gripen International corporation. Gripen is designed for the high demands put o
• Dassault RafaleThe Rafale is a sleek French twin-engine delta-wing multirole fighter aircraft designed and built by Dassault Aviation. It is being produced both for land-based use with the French air force and for carrier-based naval operation with the French Navy.
• Rutan VariViggen
• Rutan VariEzeHomebuilt aircraft The Rutan Model 31 VariEze is a composite, canard aircraft designed by Burt Rutan. The VariEze is a fairly high-performance homebuilt, hundreds of which have been constructed. The design later evolved into the Long-EZ and other, larger
• Rutan Defiant
• Rutan Long-EZ
• Cozy MK IV
• Beech Starship
• Grumman X-29A
• Sukhoi Su-35
• Atlas Cheetah
• XB-70 Valkyrie