How it works
The vertical stabilizer is a fixed vertical fin at the tail that provides directional (yaw) stability. The rudder is its hinged trailing section. Deflecting the rudder to the left pushes the tail to the right, rotating the nose left about the vertical axis — a left yaw. Deflecting it right has the opposite effect.
The vertical stabilizer's weather-vaning effect means the aircraft inherently resists uncommanded yaw and tends to align with the relative wind. The rudder works against and with this tendency to give the pilot control.
Quick reference
| Controls | Yaw (normal / vertical axis) |
| Location | Trailing edge of the vertical stabilizer |
| Movement | Single surface, deflects left or right |
| Pilot input | Rudder pedals (left foot forward = left yaw) |
Coordination, not steering: In most cruise flight, the rudder's job is to coordinate turns — balancing the adverse yaw produced by ailerons — rather than to actively steer. Directly yawing the aircraft without banking is inefficient and rarely done. The primary uses are: coordination in turns, crosswind correction on final approach and landing, and directional control during the takeoff and landing roll.