Wing Configuration - Tailplanes and Foreplanes

Tailplanes and Foreplanes

The classic aerofoil section wing is unstable in pitch, and requires some form of horizontal stabilizing surface. Also it cannot provide any significant pitch control, requiring a separate control surface (elevator) mounted elsewhere.

• Conventional - "tailplane" surface at the rear of the aircraft, forming part of the tail or empennage.
• Canard - "foreplane" surface at the front of the aircraft. Common in the pioneer years, but from the outbreak of World War I no production model appeared until the Saab Viggen appeared in 1967.
• Tandem - two main wings, one behind the other. Both provide lift; the aft wing provides pitch stability (as a usual tailplane) . An example is the Rutan Quickie. To provide longitudinal stability, the wings must differ in aerodynamic characteristics : wing loading and aerofoils must be different between the two wings.
• Three surface - used to describe types having both conventional tail and canard auxiliary surfaces. Modern examples include the Sukhoi Su-33 and Piaggio P.180 Avanti. Pioneer examples included the Voisin-Farman I and Curtiss No. 1.
• Tailless - no separate surface, at front or rear. The lifting and stabilizing surfaces may be combined in a single plane, as on the Short SB.4 Sherpa whose whole wing tip sections acted as elevons. Alternatively the aerofoil profile may be modified to provide inherent stability. Aircraft having a tailplane but no vertical tail fin have also been described as "tailless".