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FLIGHT MANAGEMENT SYSTEM

ABSTRACT

A flight management system (FMS) is a fundamental component of a modern

airliner's avionics. An FMS is a specialized computer system that automates a wide

variety of in-flight tasks, reducing the workload on the flight crew to the point that

modern aircraft no longer carry flight engineers or navigators. It helps in air traffic

control. A primary function is in-flight management of the flight plan. Using various

sensors (such as GPS and INS often backed up by radio navigation) to determine the

aircraft's position, the FMS can guide the aircraft along the flight plan. From the

cockpit, the FMS is normally controlled through a Control Display Unit (CDU) which

incorporates a small screen and keyboard or touch screen. The FMS sends the flight

plan for display on the EFIS, Navigation Display (ND) or Multifunction Display

(MFD).

The modern FMS was introduced on the Boeing 767, though earlier navigation

computers did exist. Now, systems similar to FMS exist on aircraft as small as the

Cessna 182. In its evolution an FMS has had many different sizes, capabilities and

controls.

A modern FMS is a fully integrated inertial, GPS, navigation, performance and fuel

management system controlled by an individual control and display unit.

Keywords: Flight Management System, Control Display Unit, Air Traffic Control

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CHAPTER 1

INTRODUCTION

1.1 HISTORY OF HAL

Hindustan Aeronautics Limited (HAL) came into existence on 1st October

1964. The Company was formed by the merger of Hindustan Aircraft Limited with Aeronautics India Limited and Aircraft Manufacturing Depot, Kanpur.

The Company traces its roots to the pioneering efforts of an industrialist with

extraordinary vision, the late Seth Walchand Hirachand, who set up Hindustan Aircraft Limited at Bangalore in association with the erstwhile princely State of Mysore in

December 1940. The Government of India became a shareholder in March 1941 and took over the Management in 1942.

Today, HAL has 19 Production Units and 10 Research & Design Centres in 8 locations in India. The Company has an impressive product track record - 15 types of

Aircraft/Helicopters manufactured with in-house R & D and 14 types produced under license. Hal has manufactured over 3658 aircrafts/helicopters, 4178 engines,

upgraded 272 aircrafts and overhauled over 9643 aircrafts and 29775 engines.

HAL has been successful in numerous R & D programs developed for both Defence and Civil Aviation sectors.

HAL has made substantial progress in its current projects :

Advanced Light Helicopter – Weapon System Integration (ALH-WSI)

Tejas - Light Combat Aircraft (LCA)

Intermediate Jet Trainer (IJT)

Light Combat Helicopter (LCH)

Various military and civil upgrades.

HAL has formed the following Joint Ventures (JVs) :

BAeHAL Software Limited

Indo-Russian Aviation Limited (IRAL)

Snecma

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SAMTEL-HAL Display System Limited

HALBIT Avionics Pvt Ltd

HAL-Edgewood Technologies Pvt Ltd

INFOTECH-HAL Ltd

TATA-HAL Technologies Ltd

HATSOFF Helicopter Training Pvt Ltd

International Aerospace Manufacturing Pvt Ltd

Multi Role Transport Aircraft Ltd

Several Co-production and Joint Ventures with international participation are under

consideration.

HAL's supplies / services are mainly to Indian Defence Services, Coast Guard and

Border Security Force. Transport Aircraft and Helicopters have also been supplied to

Airlines as well as State Governments of India. The Company has also achieved a foothold in export in more than 30 countries, having demonstrated its quality and price competitiveness.

HAL was conferred NAVRATNA status by the Government of India on 22nd

June 2007.

The Company scaled new heights in the Financial Year 2010-11 with Turnover of Rs.13, 116 Crores and PBT of Rs 2,841 Crores.

HAL has won several International & National Awards for achievements in R&D,

Technology, Managerial Performance, Exports, Energy Conservation, Quality

and fulfillment of Social Responsibilities.

There are several divisions under Hindustan Aeronautical Limited. They are as under:

BANGLORE COMPLEX

Aircraft Division Bangalore

Overhaul Division Bangalore

Aerospace Division Bangalore

Aircraft Services Division Bangalore

Engine Division Bangalore

Foundry and Forge Division Bangalore

IGMT Division Bangalore

Facilities Management Division Bangalore

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Mig COMPLEX

Aircraft Division Nasik

Engine Division Koraput

Aircraft Overhaul Division Nasik

Sukhoi Engine Division Koraput

ACCESSORIES COMPLEX

TAD-Kanpur Division

Accessories Division Lucknow

Avionics Division Hyderabad

Avionics Division Korwa

HELICOPTER COMPLEX

Helicopter Division Bangalore

Helicopter MRO Division Bangalore

Barrackpore Division

CMD Division Bangalore

1.2 PRESENT SETUP OF LUCKNOW DIVISION

Accessories Division of HAL was established in 1970 with the primary objective of

manufacturing systems and accessories for various aircraft and engines and attain self sufficiency in this area. Its facilities are spread over 116,000 sqm of built area set in

sylvan surroundings. At present it is turning out over 1300 different types of accessories. The Division started with manufacturing various Systems and Accessories viz, Hydraulics, Engine Fuel System, Air-conditioning and Pressurization, Flight

Control, Wheel and Brake, Gyro & Barometric Instruments, Electrical and Power Generation & Control System, Undercarriages, Oxygen System and Electronic System

all under one roof to meet the requirements of the aircraft, helicopters and engines being produced by HAL like MiG series of aircrafts, Dornier, Jaguar, Advanced Light Helicopters(ALH), PTA, Cheetah & Su-30 and repair / Overhaul of Avro, AN-32,

HPT-32, Mirage-2000 & Sea-Harrier aircrafts, Cheetah and Chetak helicopters.

The Division undertakes manufacturing and serviceing of accessories under Transfer of Technology (ToT) from more than 40 licensor from different countries. In addition, a

lot of emphasis has been given on developing indigenous capability for Design and Development of various systems and accessories. This capability has culminated in indigenous design and development of over 350 types of accessories for the Light

Combat Aircraft (LCA) (Air force and Navy version), Advanced Light Helicopter (all

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versions i.e. Army, Air force, Navy & Civil), SARAS and IJT (Intermediate Jet

Trainer). The Division has also developed and has made successful strides into the area of Microprocessor based control systems for the LCA Engine as well as other systems.

The Division has been in the forefront of accessories development and supply not only to Indian Force but to Army, Navy, Coast Guard and various Defence Laboratories as

well as for Space applications.

The Division is networked with all sister Divisions and R& D Centers by LAN/WAN. Lean manufacturing and ERP have been implemented to create an efficient

manufacturing system.

The Division today has a prime name in the Aviation market and various international companies are interested to join hands with it for future projects. The Division has also

made steady progress in the area of Export.

1.2.1 PRODUCTION OF LUCKNOW DIVISION

Products in Current Manufacturing Range

HYDRAULIC SYSTEM AND POWER CONTROL

Hydraulic Pumps, Accumulators, Actuators, Electro-selectors, Bootstrap

Reservoirs and various types of valves

ENVIRONMENTAL CONTROL SYSTEM

Cold Air Unit, Water Extractors, Non Return Valves and Venturies

ENGINE FUEL CONTROL SYSTEM

Fuel after Burner regulator and distributor, Main Fuel Distributor, Regulator and After Burner Pump, Plunger Pumps, Fuel Metering Device

INSTRUMENTS

Electrical Indicators, Fuel quantity and flow metering instruments, Flight instruments, Sensors and Switches

ELECTRICAL POWER GENERATION AND CONTROL SYSTEM

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AC/DC Generator, Control and Protection Units, AC and DC Master Box,

Inverters, Transformer Rectifier Unit, Actuators

UNDERCARRIAGE, WHEELS AND BRAKES

Main and Nose Undercarriage, Main and Nose Wheel, Brake System LRUs

TEST RIGS

Dedicated Test Rigs, custom-built Fuel/Hydraulic Test Rigs and Electrical Test Rigs.

Export Products

Supply of New along with Repair and Overhaul of Rotables and Spares of

aircraft accessories of MiG series, Jaguar International, Light Combat Aircraft (LCA), Su-30 MKI, Mirage-2000, Sea Harrier, Dornier DO-228, Avro HS-748 (Specific Version), Cheetah (Lama) / Chetak (Alouette III), MI - 17, Advanced

Light Helicopter (ALH) Helicopters to Royal Air Force Oman, Air Mauritius, Israel Aircraft Industries, ELTA Israel, Hamilton Susstrand U.S.A., Govt of

Namibia, Aerostar Romania, Ecuadorian Air Force etc.

Customers

Indian Air Force / Army / Navy / Coast Guard Defence R&D Laboratories / Department of Space

State Govt. Civil Aviation / Ordnance Factories / Corporate Sectors Flying Academics & Educational Institutions Airlines / Air Taxi / Air Cargo

Defence Forces of countries from South East Asia, Middle East and Africa Collaborators / Licensors

1.2.2 SERVICES OF LUCKNOW DIVISION

The Division carries out Repair and Overhaul of Accessories, with minimum turn-around-time. Site Repair facilities are offered by the Division by deputing team of expert Engineers / Technicians.

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Services provided for:

Military Aircraft

MiG Series

Jaguar Mirage-2000

Sea - Harrier AN-32 Kiran MK- I / MK- II

HPT - 32 SU-30 MKI

Civil Aircraft

Dornier-22B

AVRO HS-748

Helicopters

Chetak (Alouette) Cheetah (Lama)

ALH (IAF / NAVY / COAST GUARD / CIVIL)

Sub-contract Capabilities

The Division has comprehensive manufacturing capabilities for various Hi-tech components, Equipment and Systems to customer's specifications and ensures

high quality, reliability and cost effectiveness.

The Division has over 40 years of experience in producing aeronautical

accessories making it an ideal partner for the International Aero Engineering Industry.

The Division also manufactures and supplies complete range of components of Cheetah

(Lama) & Chetak (Alouette) Helicopters, Jaguar and MiG series Aircraft to Domestic and International Customers to support their fleet.

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CHAPTER 2

2.1 PRODUCTS MADE BY H.A.L. LUCKNOW

HYDRAULIC PUMP STARTER GENERATOR

MAIN ROTOR ACTUATOR

OTHER ACCESSORIES

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2.2 PRODUCTS IN CURRENT MANUFACTURING RANGE

Su 30 MKi MiG-27 M

MiG 21 Variants metallic drop tanks

Under carriage ejection seats

Canopy flexible rubber fuel tank

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2.3 HELICOPTER DIVISION

Dhruv (Advanced Light Helicopter) Dhruv (Advanced utility helicopter)

Chetak Cheetah

Lancer Cheetal

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2.4 PRODUCTS OF AEROSPACE DIVISION

2.4.1 PSLV: (POLAR SATELLITE LAUNCH VEHICLE)

No. Of Stages 4-Stage Rocket With Two Solid & Two

Liquid Stages With 6 Strap-on Motors Orbit Low Earth Polar Orbit 900 km Mission Inject 1000-1200 Kg Class Satellite (IRS) In

Polar Orbit

2.4.2 GSLV: (GEO-SYCHRONOUS SATELLITE LAUNCH VEHICLE) MK II

No. Of Stages 3-Stage Rocket with Solid, Liquid and Cryo Stages with 4 Strap-on Motors

Orbit Geo-Stationary Orbit 36000 km Mission Inject 2500 Kg Satellite INSAT Series in

Geo-Synchronous Orbit

2.4.3 GSLV: (GEO-SYCHRONOUS SATELLITE LAUNCH VEHICLE) MK III

No. Of Stages 2-Stage with Liquid and Cryo Stages and 2

Strap-on Motors Orbit Geo-Synchronous Orbit 36000 km

Mission Inject 4500 – 5000 Kg INSAT Class Satellite, in Geo-Synchronous Orbit

2.4.4 INDIAN REMOTE SENSING SATELLITE

Mission Resource Survey & Management In the area

of Agriculture, Forestry, Hydrology & Snow Melting.

Launch Vehicle PSLV

Orbit Low Earth Polar Orbit 900 km Life 5 Years

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2.4.5 INDIAN NATIONAL SATELLITE

Mission National Tele-communication, TV Broadcasting, Radio Net Working, Meteorological Observation Satellite Aided

Research & Rescue Launch Vehicle GSLV

Orbit Geo-Stationary Orbit 36000 km Life 7 Years

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CHAPTER 3

LITERATURE REVIEW

3.1 OVERVIEW – FLIGHT MANAGEMENT SYSTEM

A flight management system (FMS) is a fundamental component of a modern

airliner's avionics. An FMS is a specialized computer system that automates a wide

variety of in- flight tasks, reducing the workload on the flight crew to the point that

modern aircraft no longer carry flight engineers or navigators. The flight management

system typically consists of two units, a computer unit and a control display unit. The

computer unit can be a standalone unit providing both the computing platform and

various interfaces to other avionics or it can be integrated as a function on a hardware

platform such as an Integrated Modular Avionics cabinet (IMA). The Control Display

Unit (CDU or MCDU) provides the primary human/machine interface for data entry

and information display. Since hardware and interface implementations of flight

management systems can vary substantially, this discussion will focus on the functional

aspects of the flight management system.

Fig. 3.1 Basic Flight Management System

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The flight management system provides the primary navigation, flight planning, and

optimized route determination and en route guidance for the aircraft and is typically comprised of the following interrelated functions: navigation, flight planning,

trajectory prediction, performance computations, and guidance.

To accomplish these functions the flight management system must interface with

several other avionics systems. As mentioned above, the implementations of these interfaces can vary widely depending upon the vintage of equipment on the aircraft but generally will fall into the following generic categories:

Navigation sensors and radios

a) Inertial/attitude reference systems b) Navigation radios

c) Air data systems

Displays a) Primary flight and navigation

b) Multifunction c) Engine

Flight control system

Engine and fuel system

Data link system

Surveillance systems

A modern FMS is a fully integrated inertial, GPS, navigation, performance and fuel

management system controlled by an individual control and display unit. The major functions of a FMS are:

Reduces pilot workload and improves safety and economy

Calculates optimum flight track between departure and destination airport (L-NAV)

Calculates best profile for flight (V-NAV) – also called performance calculation

Calculates estimated time for each step for flight

Provides 4 dimensional (4D) navigation calculation

The FMS is a complex array of components whose purpose is to safely and efficiently

manage the operation of the flight. As illustrated in Figure 2-1, the FMS is composed of

navigation inputs, engine and aircraft performance monitors as well as the auto flight

and thrust management components. At the core of the FMS is the FMC.

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Fig. 3.2 Role of FMC

3.2 FUNDAMENTALS

At the center of the FMS functionality is the flight plan construction and subsequent construction of the four-dimensional aircraft trajectory defined by the specified flight

plan legs and constraints and the aircraft performance. Flight plan and trajectory prediction work together to produce the four-dimensional trajectory and consolidate all the relevant trajectory information into a flight plan/profile buffer. The navigation

function provides the dynamic current aircraft state to the other functions. The vertical, lateral steering, and performance advisory functions use the current aircraft state from

navigation and the Information in the flight plan/profile buffer to provide guidance, reference, and advisory information relative to the defined trajectory and aircraft state.

The navigation function – responsible for determining the best estimate of the

current state of the aircraft.

The flight planning function – allows the crew to establish a specific routing

for the aircraft.

The trajectory prediction function — responsible for computing the predicted

aircraft profile along the entire specified routing.

The performance function — provides the crew with aircraft unique

performance information such as takeoff speeds, altitude capability, and profile optimization advisories.

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The guidance functions — responsible for producing commands to guide the

aircraft along both the lateral and vertical computed profiles.

There are typically two loadable databases that support the core flight management functions. These are navigation database which must be updated on a monthly cycle and the performance database that only gets updated if there’s been a change in the

aircraft performance characteristics (i.e. engine variants or structural variants affecting the drag of the aircraft).

Navigation computer calculates data for lateral navigation (L-NAV) whereas Performance computer calculates data for vertical navigation (V-NAV).

Navigation

Navigation Database

Performance

Computations

Performance

Database

Trajectory

Prediction

Flight

Planning Lateral &

Vertical

Profile

Flight

Plan

Buffer

Lateral

Guidance

Vertical

Guidance

Data

link

Data entry

Fig. 3.3 Flight Management Functional Block Diagram

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3.3 Control Display Unit

FMS control display unit is the control panel of FMS computer.

It has three types of keys:

Line select keys allow selecting the function which is visible on the display next

to the key

Function keys allow to activate specific functions

Alphanumeric keyboard allows to insert data to the system

Fig. 3.3 CDU of a FMS

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Color code is used to display information on the FMS display (CDU) :

PARAMETER COLOR

Vertical data Blue (Cyan)

Atmospheric data

Lateral data Green

Index selection

FROM waypoint Yellow

TO waypoint Purple (Magenta)

Prompts and Titles White

Flight plan names Orange (Amber)

3.4 NAVIGATION DATABASE

All FMS contain a navigation database. The navigation database contains the elements from which the flight plan is constructed. These are defined via the ARINC 424 standard. The navigation database (NDB) is normally updated every 28 days, in order to ensure that its contents are current. Each FMS contains only a subset of the ARINC

data, relevant to the capabilities of the FMS.

The NDB contains all of the information required for building a flight plan, consisting of:

Waypoints/Intersection

Airways (highways in the sky) Radio navigation aids including distance measuring equipment (DME), VHF

omni directional range (VOR), non-directional beacons (NDBs) and instrument landing systems (ILSs).

Airports

Runways Standard instrument departure (SID)

Standard terminal arrival (STAR) Holding patterns (only as part of IAPs-although can be entered by command of

ATC or at pilot's discretion)

Instrument approach procedure (IAP)

Waypoints can also be defined by the pilot(s) along the route or by reference to other waypoints with entry of a place in the form of a waypoint (e.g. a VOR, NDB, ILS,

airport or waypoint/intersection).

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3.5 L-NAV

Navigation computer of FMC uses navigation database to store navigation data for flight operation. This database is updated every 28 days by maintenance organization.

Navigation computer creates flight plan and gives desired position for all steps of flight, for input pilot must enter company route on CDU.

Desired position from flight plan will be compared to the current position, this gives us the position error which will be sent to AP/FD computer as NAV steering signal.

Autopilot uses this signal to change aircraft movement around three axes.

FMC calculates present positions from signals of different sensors: GPS, IRS, VOR,

ILS, etc. Present position of aircraft is given by IRS, starting position of the aircraft must be selected from FMS during IRS alignment. During flight IRS position corrected

by GPS and if necessary navigation radios- DME, VOR, LOC all these stations will be automatically tuned by FMS.

FMS data presented on EFIS Navigation Display uses aircraft symbol shows present position in relation to flight plan.

L-NAV produces roll steering command to the autopilot.

3.6 V-NAV

Task of vertical navigation part of FMS is:

To optimize vertical flight profile

To calculate optimum speed for each flight phase

To calculate necessary thrust for engines (thrust limit calculation) Necessary aircraft and engine performance data is stored in performance database.

Optimum aircraft speed depends on many factors:

Environmental conditions – air pressure and temperature from ADC

Aircraft weight

Fuel and time costs

Sophisticated aircraft, generally airliners such as the Airbus A320 or Boeing 737 and larger, have full performance VNAV or Vertical Navigation. The purpose of VNAV is

to predict and optimize the vertical path. Guidance includes control of the pitch axis and control of the throttle.

In order to have the information necessary to accomplish this, the FMS must have a

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detailed flight and engine model. With this information, the function can build a

predicted vertical path along the lateral flight plan. This detailed flight model is generally only available from the aircraft manufacturer.

During pre-flight, the FMS builds the vertical profile. It uses the initial aircraft empty weight, fuel weight, centre of gravity and initial cruise altitude, plus the lateral flight

plan. A vertical path starts with a climb to cruise altitude. Some SID waypoints have vertical constraints such as "At or ABOVE 8,000". The climb may use a reduced thrust(derated) or "FLEX" climb to save stress on the engines. Each must be considered

in the predictions of the vertical profile.

Implementation of an accurate VNAV is difficult and expensive, but it pays off in fuel savings primarily in cruise and descent. In cruise, where most of the fuel is burned, there are multiple methods for fuel savings.

As an aircraft burns fuel it gets lighter and can cruise higher where it is generally more efficient. Step climbs or cruise climbs facilitate this. VNAV can determine where the step or cruise climbs (where the aircraft drifts up) should occur to minimize fuel

consumption.

Performance optimization allows the FMS to determine the best or most economical speed to fly in level flight. This is often called the ECON speed. This is based on the

cost index, which is entered to give a weighting between speed and fuel efficiency. Generally a cost index of 999 gives ECON speeds as fast as possible without consideration of fuel and a cost index of Zero gives maximum efficiency. ECON mode

is the VNAV speed used by most airliners in cruise.

An ideal idle descent, also known as a “green descent” uses the minimum fuel, minimizes pollution (both at high altitude and local to the airport) and minimizes local

noise. While most modern FMS of large airliners are capable of idle descents, most air traffic control systems cannot handle multiple aircraft each using its own optimum descent path to the airport, at this time. Thus the use of idle descents is minimized by

Air Traffic Control.

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CHAPTER 4

OUTSOURCING

The outsourcing activity started in the Division way back in 2003. Since then Division

has embarked upon selecting and creating base of sub-contractors for outsourcing precision components, tooling and test equipment. This is required to handle higher

loads of existing and new projects being undertaken in the division.

The outsourcing is done in the following areas:

1. Machining of components involving turning turning, milling, drilling, jig boring, grinding, centre-less grinding, lapping etc.

2. Machining / Fabrication of tools, jigs and fixtures.

3. Specialized processes like Ion - Nitriding, Tungsten Carbide Coating, Laser Beam

Welding, Electron Beam Welding, Moulding etc.

Apart from the above production work packages, Design work packages are also outsourced.

The components are classified in various families like A, B & C depending upon the

criticality of the operations. Depending on the capabilities of sub-contractors, tenders are being issued to respective registered vendors.

Organizations with established facilities & capabilities, willingness to learn and excel

in producing aeronautical quality product are encouraged for outsourcing of components required for various projects.

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CONCLUSION

This report is an introduction to the several functions that comprise a flight

management system and has focused on the basic functionality and relationships that are fundamental to understanding the flight management system and its role in the operations of the aircraft. Clearly, there is a myriad of complexity in implementing

each function that is beyond the scope of this publication.

The future evolution of the flight management system is expected to focus not on the core functions as described herein, but on the utilization within the aircraft and on the ground of the fundamental information produced by the flight management system

today. The use of the FMS aircraft state and trajectory intent, within the aircraft and on the ground, to provide strategic conflict awareness is a significant step toward better

management of the airspace. Communication of the optimized user-preferred trajectories will lead to more efficient aircraft operation. The full utilization of RNP-based navigation will increase the capacity of the airspace. Innovative methods to

communicate FMS information and specify flight plan construction with the crew to make flight management easier to use are expected as well. Clearly, the FMS is a key

system in moving toward the concepts embodied in CNS future airspace. FMS performs all the calculations and predictions required to determine the most

economical flight profile, either for minimum fuel or minimum time. When coupled to the automatic flight control system, with lateral and vertical navigation modes engaged

the flight crew act as managers monitoring and entering data as required. Much of the data presented on the CDU is also displayed in the primary flight displays, aircrafts with electronic flight instruments have the advantage in that the information is

displayed with colored symbols to identify key features of the flight plan, e.g. navigation aids, airfields and descent points.