Certified Flight Instructor - Flight Instructor Airplane Practice Exam

What is the main purpose of the aircraft’s rudder during flight?

1. Increase lift.

2. Control yaw.

3. Stabilize pitch.

4. Control roll.

The correct answer is: Control yaw.

The rudder's primary function during flight is to control yaw, which refers to the side-to-side movement of the aircraft's nose. By deflecting the rudder left or right, the pilot can create a yawing moment that can either turn the aircraft in the desired direction or counteract adverse yaw that can occur during turns. This capability is essential for maintaining coordinated flight, particularly during maneuvers such as turns or when compensating for wind conditions. While controlling lift, pitch, and roll are important aspects of an aircraft's flight dynamics, they are predominantly managed by other control surfaces such as ailerons (for roll) and elevators (for pitch). The rudder's exclusive responsibility for yaw makes it a fundamental component in ensuring that the aircraft responds accurately to the pilot’s inputs and maintains stability in flight.