What mechanism is used to select vertical and lateral modes along with speed control in an aircraft?

The Flight Control Unit is the primary interface for selecting vertical and lateral navigation modes, as well as managing speed control in an aircraft. This unit allows pilots to engage various autopilot modes and configure the flight management system as needed for specific flight operations.

By using the Flight Control Unit, pilots can toggle between different modes such as heading, vertical speed, or altitude hold, and make adjustments to speed settings. This centralized control minimizes workload and enhances situational awareness, allowing pilots to focus on other critical aspects of flight.

Other tools, like the Flight Management Computer, assist in navigation and performance calculations but do not directly provide the control interface for selecting modes. Similarly, while the control stick is critical for manual flight control, it does not facilitate the selection of autopilot modes or speed. The throttle quadrant is primarily used for engine thrust management and is essential for speed adjustments, but it does not encompass orientation control. Therefore, the Flight Control Unit is the correct choice for managing these functions effectively.