Which control surface is responsible for changing an aircraft's pitch?

The control surface that is responsible for changing an aircraft's pitch is the elevators. Elevators are located on the tail section of the aircraft and are part of the horizontal stabilizer. When the pilot moves the control yoke or stick forward or backward, the elevators change their angle of deflection.

When the elevators are deflected upwards, they increase the angle of attack at the tail, resulting in a downward force on the tail and causing the nose of the aircraft to pitch up. Conversely, when the elevators are deflected downwards, they decrease the angle of attack, resulting in an upward force on the tail and causing the nose to pitch down. This ability to control pitch is crucial for managing the aircraft's altitude and angle of ascent or descent during flight.

In contrast, ailerons control the roll of the aircraft, effectively managing its lateral axis, while the rudder affects yaw, controlling the left or right movement of the aircraft's nose. Flaps are used primarily to increase lift during takeoff and landing, modifying the wing's shape rather than directly affecting pitch.