Fms Fmc

🧭 Flight Management System (FMS) — Simple Explanation

The Flight Management System (FMS) is an integrated navigation and performance system that automates most of the tasks needed to manage a flight.

It combines:

• Navigation (where the aircraft is and where it’s going)
• Performance (how fast, how high, how efficient)
• Guidance (telling the autopilot how to follow the route)

⚙️ Main Functions

• Stores and follows the flight plan (waypoints, airways, procedures)
• Uses GPS, IRS, and radio aids to calculate the exact position
• Provides lateral (LNAV) and vertical (VNAV) guidance to the autopilot
• Calculates fuel, ETA, and optimal climb/descent profiles

🧩 Main Components

✅ In short:

The FMS is the aircraft’s navigation and performance manager — it plans, monitors, and guides the flight automatically, using data from multiple sensors to fly the most efficient route.

🧭 Flight Management Computer (FMC) — Simple Explanation

The Flight Management Computer (FMC) is the main brain of the Flight Management System (FMS).

It:

• Stores and manages the flight plan (route, waypoints, speeds, altitudes).
• Calculates the most efficient flight path, speed, and fuel use.
• Sends guidance commands to the autopilot and autothrust to follow the programmed route.

🧩 Main Functions

• Navigation: determines the aircraft’s position using IRS, GPS, and radio aids.
• Performance: calculates optimum speeds, climb/descent profiles, and fuel predictions.
• Guidance: provides lateral (LNAV) and vertical (VNAV) path commands to the flight director/autopilot.

💻 Inputs & Outputs

✅ In short:

The FMC is the computer inside the FMS that calculates and controls the most efficient and accurate way for the aircraft to follow its planned route — automatically guiding navigation, performance, and fuel management.