A ruddervator is a type of control surface that combines the functions of both a rudder and an elevator. It is used on an aircraft with a V-tail configuration, which has two slanted tail surfaces instead of the conventional horizontal and vertical stabilizers.
The ruddervators are located at the trailing edge of each of the two airfoils making up the tail of the plane.
When the pilot moves the control column forward or aft, the ruddervators move symmetrically to change the pitch of the aircraft. When the pilot moves the rudder pedals, the ruddervators move differentially to change the yaw of the aircraft.
The ruddervators can also move simultaneously to produce a combined pitch and yaw effect.