What does the throttle quadrant control in an aircraft cockpit?

The throttle quadrant is a pivotal component in an aircraft cockpit that is primarily responsible for controlling engine power settings. This control is essential for managing the thrust produced by each engine, allowing the pilot to adjust power output during various phases of flight, such as takeoff, cruising, and landing.

By manipulating the throttle levers in the quadrant, pilots can effectively increase or decrease engine power as required for performance and operational needs. This includes adjustments for climbing, descending, and maintaining level flight, thereby directly influencing the aircraft's speed and altitude.

The other options represent different systems within the cockpit that do not relate to engine power management. While navigation systems assist in route planning and guidance, emergency protocols are focused on handling critical flight situations, and flight communication systems manage communication with air traffic control and other aircraft. These systems are crucial for safe and efficient operation of the aircraft, but they do not involve the direct control of engine power, which is the primary function of the throttle quadrant.