What is the primary function of the flight management system (FMS)?

The primary function of the flight management system (FMS) is to manage navigation and route planning. The FMS integrates and processes information from various inputs, including navigational data, aircraft performance parameters, and flight plans, allowing the crew to optimize the flight path and ensure efficient fuel usage. It assists in calculating the most effective routing and helps manage changes in altitude or heading, enhancing overall flight safety and efficiency.

The FMS is crucial during all phases of flight, as it can automatically control the aircraft's flight path based on the planned route, which significantly reduces pilot workload. By using an integrated set of systems, such as GPS, inertial navigation systems, and air traffic data, the FMS allows pilots to focus more on overall flight management rather than just navigation, making it an indispensable tool in modern aviation.