Which of the following is NOT classified as a secondary flight control?

The concept of primary and secondary flight controls is fundamental in understanding aircraft design and operation. Primary flight controls are essential for basic maneuvering of the aircraft and include ailerons, elevators, and rudders. These controls are directly responsible for controlling the aircraft's pitch, roll, and yaw.

In contrast, secondary flight controls enhance the performance of the primary controls and help improve the aircraft's handling, efficiency, and safety, especially during specific phases of flight. Secondary controls include flaps, which increase lift and drag, and trim systems that help relieve pilot workload by maintaining desired flight attitudes.

The elevator is classified as a primary flight control because it directly manipulates the aircraft's pitch. In flight operations, the elevator's primary function is to control the angle of attack and maintain or change altitude, making it crucial for basic flying capabilities.

Consequently, identifying the elevator as a primary control solidifies the understanding that it is fundamentally important for the aircraft's maneuverability, while options like flaps and trim are considered secondary controls that assist the pilot without being essential for flight itself.