Which of the following best describes primary flight controls?

• A. Secondary controls include flaps, slats, spoilers, and trim.
• B. They regulate cabin pressurization through bleed air and outflow valves.
• C. Primary controls are for basic vehicle control (ailerons, elevator, rudder).
• D. They are mainly used to manage engine speed and fuel with FADEC.

Answer: (C)

The main concept is that primary flight controls are the surfaces that directly govern the aircraft’s basic attitudes and flight path. They provide the pilot with control over roll, pitch, and yaw, using the ailerons for bank, the elevator for nose-up/nose-down movement, and the rudder for left-right yaw. This direct control of the airplane’s attitude is what makes them the fundamental flight controls in normal flight. Secondary controls, like flaps, slats, spoilers, and trim, adjust lift, drag, and stability but don’t command the basic attitude in the same way. Environmental systems such as cabin pressurization and the engine control system (FADEC) handle different functions altogether, not the primary maneuvering surfaces.