1. Lecture 11: Flight Management System (FMS)

2. Introduction Modern aircraft are filled with the latest technology.
Technology which greatly reduces workload if the systems are understood and used properly.
The heart of all these systems is the FMS.

3. What is FMS?
FMS is stand for Flight Management System (FMS) is a specialized computer system that automates a wide variety of in-flight tasks.
FMS acts as the ‘brain’ of the aircraft navigation system.
The Flight Management System (FMS) can be thought of as the ‘brain’ of the aircraft navigation system, which assists pilots in navigation and flight preparation to compute the most efficient flight in fuel and time savings and automatically navigate the aircraft. It calculates performance data and the most fuel-efficient route to be flown based on typical aircraft parameters such as weight, cruise altitude and actual aircraft position, regardless of weather conditions.

4. FMS Components
From the cockpit, the FMS is normally controlled through a Control Display Unit (CDU) which incorporates a small screen and keyboard.
The FMS sends the flight plan for display on the EFIS, Navigation Display (ND)
Control Display Unit

5. FMS Components
Control Display Unit
Navigation Display

6. FMS database FMS Contains two types database which are:
NAVIGATION DATABASE
PERFORMANCE DATABASE
The flight plan is generally determined on the ground, before departure either by the flight dispatcher for airliners.
It is entered into the FMS either by typing it in, selecting it from a saved library of common routes (Company Routes) or via an datalink with the airline dispatch center.

7. FMS navigation database
All FMS contain a navigation database.
The navigation database contains the elements from which the flight plan is constructed.
Navigation Database include
Waypoints,
Airways (highways in the sky)
Radio navigation aids (DME,VOR,ILS)
Airports (Runways), Holding patterns
And a variety of other related information
The flight plan is generally determined on the ground, before departure either by the flight dispatcher for airliners.
It is entered into the FMS either by typing it in, selecting it from a saved library of common routes (Company Routes) or via an datalink with the airline dispatch center.

8. FMS performance database
During preflight, other information relevant to managing the flight plan is entered.
This can include performance information such as
Maximum take-off weight,
Fuel weight
Center of gravity.
It will include altitudes including the initial cruise altitude.

9. Flight Management Computer Input/output
The FMS is capable of :
Calculating optimum rate of climb/descent, altitude, power setting.
Controlling the aircraft to meet these optimum parameters through autopilot and auto-throttle.
Guiding pilot controlled flight path through a flight director, and target speed and engine setting bugs.
Cross referencing multiple navigation sources to continually update position.
Automatically tuning en-route navaids.
Alerting pilots of systems status and malfunctions.

10. FMS Operation Pilot key in input route information to CDU of FMS
The navigation and aircraft performance database must be verified.
Routing must be confirmed accurate and correct and any ATC changes to expected routing must be entered manually.
The pilot becomes a manager of this sophisticated system, monitoring progress and updating or changing parameters as necessary.
The pilot must initialize and program the FMS with relevant route information.
The navigation and aircraft performance database must be verified as current and correct. (performance must reflect the specific aircraft)
An initial position must be entered. (Lat and Long)
The required route must be entered. This can include specific departure, en-route, arrival, and approach procedures. (manually entered or previously stored)
Routing must be confirmed accurate and correct and any ATC changes to expected routing must be entered manually en-route.
The pilot becomes a manager of this sophisticated system, monitoring progress and updating or changing parameters as necessary.

11. FMS Advantages FMS are designed to : Improve Navigation
Aid Fuel Efficiency
Reduce Crew Workload
More Accurate

12. FMS Advantages FMS are designed to: Navigation Aid Fuel Efficiency
A principal task of the FMS is to determine the aircraft's position and the accuracy of that position.
Given the flight plan and the aircraft's position, the FMS calculates the course to follow.
Autopilot can be set to follow the course.
Aid Fuel Efficiency
It calculates performance data and the most fuel-efficient route to be flown based on typical aircraft parameters such as weight, cruise altitude and actual aircraft position, regardless of weather conditions.

13. FMS Advantages Reduce Crew Workload More Accurate.
Allows pilots more time to analyze and make decisions. (drink coffee too)
More Accurate.
Computer generated efficiency profiles are more accurate.
Navigation accuracy is improved through integration and cross referencing of multiple sources.
The Flight Management Computer is supplied with information from:
Navigation systems
Inertial reference system
Air data computer
Engine and system status
Aircraft specific performance database
Route, procedure and terrain database
EGPWS
TCAS
Datalink
Pilot inputs
It analyzes these inputs and continually reevaluates changing parameters to provide the autopilot, flight director, and auto-throttles with commands which optimize all aspects of a flight.

14. FMS Disadvantages Error Data Entry Loss of situational awareness
Reliant on pilot input.
There is potential of misinterpretation or erroneous data entry.
Loss of situational awareness
Loss of situational awareness. Pilots may become so involved in operating and monitoring the system that they forget to look outside.
Expensive.

15. Question Bank
1. a) Describe about FMS? b) Explain advantages and disadvantages of FMS