What aspect of flight planning does an FMS optimize?

An FMS, or Flight Management System, is designed to integrate and optimize a variety of aspects related to flight planning, navigation, and performance all in one system. When considering navigation, the FMS calculates and determines the most efficient flight paths based on various parameters, such as airways, waypoints, and current weather conditions.

In terms of performance, the system can analyze aircraft capabilities, predicted weight, and balance, as well as external factors such as wind and altitude. It provides crucial information that helps pilots make informed decisions about fuel management, speed, and altitude changes throughout the flight.

Additionally, the FMS aids in the overall planning of a flight, helping pilots to generate optimized routes and manage changes in real-time, especially during unforeseen circumstances. This integration of navigation, performance data, and planning processes collectively enhances the efficiency and safety of a flight.

Therefore, recognizing that the FMS addresses a broader spectrum of flight planning aspects rather than focusing solely on one area like fuel efficiency or pilot workload, makes it clear why the optimization of navigation, performance, and planning is the correct and comprehensive answer.