In flight deck terminology, what is the primary purpose of the Control Display Unit?

• A. To provide the pilot with a single control point for all navigation systems, thereby reducing flight deck panels
• B. To monitor cabin pressure
• C. To display wind speed only
• D. To control engine thrust directly

Answer: (A)

The controls used for navigation data input and flight planning are centralized in one interface, the Control Display Unit. It serves as the pilot’s interface to the Flight Management System, giving a single place to input and edit routes, waypoints, altitudes, speeds, and other navigation parameters. The data entered on the CDU is used by the FMS to compute the flight plan and is shown on the navigation displays, helping you plan and adjust the route efficiently. By consolidating navigation control into one unit, it reduces the number of separate panels needed for navigation.

This unit isn’t for monitoring cabin pressure, nor is it limited to displaying wind speed, and it doesn’t directly control engine thrust—the thrust is managed by the engines and autothrottle system, while the CDU provides the data and inputs that guide navigation and flight planning.