Which type of avionics system is designed to calculate the best route for a flight?

The Flight Management System (FMS) is specifically designed to calculate the best route for a flight. It integrates multiple functions, including navigation, performance management, and flight planning. By processing various inputs such as wind speed, aircraft weight, and air traffic control updates, the FMS can optimize the flight path to ensure efficiency and safety.

This system continuously updates the aircraft's trajectory, allowing pilots to manage the flight more effectively while minimizing fuel consumption and ensuring timely arrivals. The FMS also assists in managing complex airspace and can automatically adjust the route in response to changing conditions, making it an essential component of modern avionics.

In contrast, while other systems like the Flight Dynamics System, Navigation Communication System, and Ground Control System play important roles in aviation operations, they do not focus specifically on route calculation in the same comprehensive manner as the FMS.