Which of the following is listed as a secondary flight control?

• A. Elevators
• B. Ailerons
• C. Rudder
• D. Spoilers

Answer: (D)

Understanding flight control categories helps: primary controls are the ones pilots use to directly establish the aircraft’s attitude—elevator for pitch, ailerons for roll, and the rudder for yaw. Secondary flight controls modify how the airplane flies rather than set its immediate attitude. Spoilers fit this role: they deploy to disrupt lift and add drag, aiding descent and speed control, and in some designs can assist with roll. Because their primary job isn’t to directly command pitch, roll, or yaw, they’re considered secondary. The other surfaces—elevators, ailerons, and the rudder—are primary controls since they directly govern pitch, roll, and yaw.