Stabilator - General Aviation

General Aviation

Because it involves a large moving surface, a stabilator can allow the pilot to generate greater pitching moment with little effort. Due to the high forces involved in tail balancing loads, stabilators are designed to pivot about their aerodynamic center (at the tail's quarter-chord). This is the point at which the pitching moment is constant regardless of the angle of attack, and thus any movement of the stabilator can be made without added pilot effort. An airplane certified by the appropriate regulatory agency (e.g. the US Federal Aviation Administration) must show an increasing resistance to an increasing pilot input (movement), so to provide this resistance, stabilators on small aircraft contain an anti-servo tab (sometimes combined with the trim tab) that deflects in the same direction as the stabilator, thus providing an aerodynamic force resisting the pilot's input. General aviation aircraft with stabilators include the Piper Cherokee and the Cessna 177.