Manual Entrenamiento Arrius Ia

0.1

ARRIUS 1

For training purposes only© Copyright - TURBOMECA Edition: May 2006

Training Notes

FOREWORDThis document is intended to assist a TURBOMECA qualified instructor inteaching basic information related to the operation and maintenance of theARRIUS 1 turboshaft engine.

It is a training aid and should only be used to support the training course towhich it refers and only by a person attending such training. It must not be usedin any other circumstances.

It will not be updated and should not be relied upon for maintenance or repairof ARRIUS 1 engines. Only the approved and current TURBOMECA mainte-nance technical publications should be used for such purposes.

The acquisition of this document does not constitute proof of official formaltraining. Only completion of a course delivered by a TURBOMECA qualifiedinstructor can lead to the issuance of a TURBOMECA recognized training coursecertificate, stating when applicable a successful result.

This document is the property of TURBOMECA and it may not be copied without the express authority of TURBOMECA.

FOREWORD

0.2For training purposes only© Copyright - TURBOMECA

ARRIUS 1

Edition: May 2006

Training Notes

SUMMARY

0 - Foreword

1 - Introduction

2 - Power plant

3 - Engine

4 - Oil system

5 - Air system

6 - Fuel system

7 - Control system

8 - Measurement and indicatingsystems

9 - Starting

10 - Electrical system

11 - Engine installation

12 - Operating limitations andprocedures

13 - Various aspects of maintenance

14 - Maintenance procedures

15 - Trouble shooting

16 - Checking of knowledge

SUMMARY

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ARRIUS 1


Training Notes

TABLE OF CONTENTS0 - FOREWORD

- Summary ............................................ 0.2

- Table of contents ................................ 0.3

- List of abbreviations .......................... 0.7

- Conversion table ................................ 0.10

1 - INTRODUCTION

- General information ........................... 1.2

- Training method ................................. 1.4

- Training aids ...................................... 1.6

- Training programme ......................... 1.8 to 1.14

2 - POWER PLANT

- Power plant ........................................ 2.2

• General ........................................... 2.2• Description ..................................... 2.4• Operation ....................................... 2.6

- Principle of adaptation to the

helicopter ........................................... 2.10

- Main characteristics ........................... 2.12

- Design and development ................... 2.18 to 2.21

3 - ENGINE- Engine ................................................ 3.2

- Air intake ........................................... 3.8

- Compressor ........................................ 3.10

- Combustion chamber ......................... 3.16

- Gas generator turbine ......................... 3.22

- Power turbine ..................................... 3.28

- Exhaust system .................................. 3.34

- Reduction gearbox ............................. 3.38

• Reduction gear train ....................... 3.40• Accessory drive train ...................... 3.46 to 3.51

4 - OIL SYSTEM- Oil system ......................................... 4.2

- Oil reservoir ....................................... 4.8

- Oil pumps ........................................... 4.10

- Oil filter .............................................. 4.14

- Pre-blockage pressure switch............. 4.20

TABLE OF CONTENTS


ARRIUS 1

Edition: May 2006

Training Notes

TABLE OF CONTENTS(CONTINUED)

6 - FUEL SYSTEM- Fuel system ....................................... 6.2

- Fuel pressure transmitter .................... 6.16

- LP fuel pump - Alternator unit ........... 6.18

- Fuel filter ............................................ 6.24

- Pre-blockage pressure switch............. 6.30

- HP fuel pump and metering unit ........ 6.32

- Stop electro-valve .............................. 6.38

- Fuel valve assembly ........................... 6.42

- Start injectors ..................................... 6.48

- Main injectors .................................... 6.54

- Combustion chamber drain valve ...... 6.60

- Fuel pipes ........................................... 6.62 to 6.63

7 - CONTROL SYSTEM- Control system ................................... 7.2

• General ........................................... 7.2• Description ..................................... 7.4• Operation ........................................ 7.6

4 - OIL SYSTEM (CONTINUED)- Cooling unit ....................................... 4.22

- Centrifugal breather ........................... 4.24

- Electrical magnetic plugs ................... 4.26

- Strainers ............................................. 4.28

- Low oil pressure switch ..................... 4.30

- Oil pressure transmitter ...................... 4.32

- Oil temperature probe ........................ 4.34

- Oil pipes ............................................. 4.36 to 4.37

5 - AIR SYSTEM- Air system ......................................... 5.2

- Internal air system ............................. 5.4

- Air tappings........................................ 5.6

- Air tapping unions ............................. 5.8

- Air pressure sensor ............................. 5.10

- Air temperature probe ........................ 5.12 to 13

TABLE OF CONTENTS

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Training Notes


7 - CONTROL SYSTEM (CONTINUED)- Digital Control Unit .................................. 7.34

•General .................................................... 7.34•Functional description ............................. 7.36 to 7.39

8 - MEASUREMENT AND INDICATINGSYSTEMS

- Measurement and indicating systems ....... 8.2

- Speed measurement and indicating

system ................................................ 8.4

•N1 speed sensor....................................... 8.6•N2 speed sensors ..................................... 8.10

- Gas temperature measurement andindicating system ...................................... 8.14•Thermocouple probes and t4.5conformation box .................................... 8.16

- Torque measurement and indicatingsystem ....................................................... 8.20•Torque transmitter ................................... 8.24

- Miscellaneous indications ......................... 8.26

•Indicators ................................................. 8.26•∆N1 measurement and indicating system ...... 8.28•Display system ........................................ 8.30 to 8.33

9 - STARTING- Starting system................................... 9.2

- Starter ................................................. 9.6

- Ignition system................................... 9.10

• Ignition unit .................................... 9.12• Igniter plugs .................................... 9.14• Ignition cables ................................ 9.16 to 9.17

10 - ELECTRICAL SYSTEM- Electrical system ................................ 10.2

- Alternator ........................................... 10.4

- Electrical harnesses ............................ 10.6 to 10.7

11 - ENGINE INSTALLATION- Engine compartment .......................... 11.2

- Engine mounting and lifting .............. 11.4

- Power drive ........................................ 11.6

- Air intake ........................................... 11.8

- Exhaust system .................................. 11.10

- Drain system ...................................... 11.12

- Fire protection .................................... 11.14 to 11.15

TABLE OF CONTENTS


ARRIUS 1

Edition: May 2006

Training Notes


15 - TROUBLE SHOOTING- General ............................................... 15.2

- Trouble shooting ................................ 15.4 to 15.23

16 - CHECKING OF KNOWLEDGE- Introduction ........................................ 16.2

- Questionnaire 1 ................................. 16.3

- Questionnaire 2 ................................. 16.6

- Questionnaire 3 ................................. 16.12

- Questionnaire 4 .................................. 16.15 to 16.17

OBSERVATIONS ..................................... Last page

These training notes are established to meet trainingrequirements and take into consideration, to a certain extent,ATA 104 specifications.

This document has 397 pages. It was produced using adesktop publishing system

12 - OPERATING LIMITATIONS ANDPROCEDURES

- Operating limitations ......................... 12.2

- Operating procedures ........................ 12.4 to 12.7

13 - VARIOUS ASPECTS OF MAINTENANCE- Maintenance concept ......................... 13.2

- Life limitation .................................... 13.4

- Preventive maintenance ..................... 13.6

- "On-condition" monitoring ................ 13.8

- Corrective maintenance ..................... 13.10

- Technical publications ....................... 13.12 to 13.15

14 - MAINTENANCE PROCEDURES- General ............................................... 14.2

- 1st line (O level) ................................ 14.4

- 2nd line (I level) ................................. 14.8

- 3rd line (H level) ................................ 14.10

- 4th line (D level) ................................ 14.12 to 14.13

TABLE OF CONTENTS

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Training Notes

EGT .............. Exhaust Gas TemperatureF .................... FrequencyFAA .............. Federal Aviation AgencyFADEC ......... Full Authority Digital Engine ControlFCU .............. Fuel Control Unitft .................... FeetFLI ................ First Limit IndicatorFOD .............. Foreign Object DamageFWD ............. ForwardG ................... Mass air flowHE ................. High EnergyHP ................. Horse PowerHP ................. High PressurehPa ................ Hecto PascalHUMS........... Health and Usage Monitoring SystemHz ................. HertzID .................. IdentificationILS ................ Integrated Logistic SupportIRAN ............ Inspect and Repair as Necessary

A/C ............... AircraftAC................. Alternating CurrentACW ............. Anti-clockwiseADP .............. Aero Design PointAEO .............. All Engines OperatingATA .............. Air Transport AssociationBITE ............. Built In Test EquipmentC ................... Torquecc/h ............... Cubic centimetres per hourCDS .............. Cockpit Display SystemCFT ............... Frequency/Voltage ConverterCH................. Fuel consumptionCW ................ ClockwisedB ................. DecibelDC................. Direct CurrentDGAC ........... Direction Générale de l'Aviation CivileDMC ............. Direct Maintenance CostEc .................. Kinetic energyEECU ............ Engine Electronic Control Unit

LIST OF ABBREVIATIONS

The abbreviations / symbols shown below may be used during training:

LIST OF ABBREVIATION


ARRIUS 1

Edition: May 2006

Training Notes

LIST OF ABBREVIATIONS(CONTINUED)

ISA ................ International Standard AtmospherekHz ............... KilohertzkPa ................ KilopascalkW ................ Kilowattlb ................... Poundlb/hr ............... Pounds per hourlb/sec. ............ Pounds per secondlb/HP.hr ........ Pounds per Horse Power per hourLCD .............. Liquid Crystal DisplayLP ................. Low PressureLRU .............. Line Replaceable UnitLTT ............... Learning Through TeachingLVDT ........... Linear Voltage Differential Transducerm ................... MetremA ................ MilliampereMAX ............. MaximumMCP .............. Max. Continuous PowerMCQ ............. Multi Choice QuestionnaireMGB ............. Main gearboxMHz .............. Mega HertzMIN .............. Minimum

mm ................ MillimetreMTBF ........... Mean Time Between FailureMTBUR ........ Mean Time Between Unscheduled RemovalmV ................ MillivoltN ................... Rotation speedN1 ................. Gas generator rotation speedN2 ................. Power turbine rotation speedNOVRAM .... Non Volatile Read Only MemoryNR................. Rotor rotation speedO/S ................ OverspeedOEI ............... One Engine InoperativeP .................... PressureP3 .................. Compressor outlet pressurePH ................. Oil pressurePOS ............... PositionPT ................. Power TurbineQ ................... Fuel flowRAM ............. Random Access MemoryROM ............. Read Only MemoryRPM .............. Revolutions Per MinuteRTD .............. Resistive Temperature Device


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Training Notes

LIST OF ABBREVIATIONS(CONTINUED)

SFC ............... Specific Fuel ConsumptionPSI ................ Pounds per Square InchPSID ............. Pounds per Square Inch DifferentialShp ................ Shaft horse powerSI ................... International Systemt ..................... TimeT/O ................ Take-OffTBO .............. Time Between OverhaulTET ............... Turbine Entry Temperaturet° ................... Temperaturet°4.5 ............. Gas temperaturet°H................. Oil temperatureUS G ............. US GallonVAC .............. Volt, Alternating CurrentVDC .............. Volt, Direct CurrentVEMD .......... Vehicle and Engine Multifunction Display


W .................. PowerZ .................... AltitudeZp .................. Pressure altitude

°C .................. Degrees Celsius°F .................. Degrees Fahrenheit°K.................. Degrees Kelvin± .................... Positive and negative for electrical circuits≈ .................... ApproximatelyΩ ................... OhmµP.................. Micro-processor∆ .................... Difference∆P ................. Pressure difference% ................... Percent< .................... Is lower than> .................... Is higher than


ARRIUS 1

Edition: May 2006

Training Notes

International System British or American Systems

1 mm = 0.039 inch1 m = 3.28 ft = 1.09 yard

1 dm3 = 1 litre = 0.26 US gallon

1 kg = 2.2 lbs

1 kW = 1.34 HP

°C = (°F-32). 5/9°K = [(°F-32)5/9] + 273

1 kPa = 0.01 bar = 0.145 PSI

1 kg/s = 2.2 lbs/sec.

1 g/kW.h = 0.00164 lb/HP.hr

Length

Volume

Mass

Power

Temperature

Pressure

Flow (air, oil, fuel)

Specific Fuel Consumption

CONVERSION TABLEUNITS

CONVERSION TABLE

1.1INTRODUCTION

ARRIUS 1


Training Notes

1 - INTRODUCTION

- General information............................................... 1.2

- Training method ..................................................... 1.4

- Training aids ........................................................... 1.6

- Training programme ............................................. 1.8 to 1.14

1.2INTRODUCTION

For training purposes only© Copyright - TURBOMECA

ARRIUS 1

Edition: May 2006

Training Notes

GENERAL INFORMATION

«The power of knowledge»

Adequate training is essential for obvious safety reasons,but also to reduce additional maintenance costs incurredby unjustified removals and excessive downtime.

"Greater knowledge leads to greater efficiency".

Objectives of training

The main objective is the acquisition of the knowledgerequired for the tasks to be achieved (know and knowhow).

Further information is also communicated to widen theskill and the experience of the trainee.

Training approach

- Performance based training according to taskanalysis, with classroom sessions, student involvement,practical work and troubleshooting techniques

- Advanced training aids: training notes, Computer AidedPresentation (or overhead projection), multimediacourseware and demonstration mock-ups

- Experienced and formally trained instructors

- Courses are taught in English and French and, inspecial circumstances, in German and Spanish.

Training Centre

The Training Centre is located in one of the buildings ofTURBOMECA's TARNOS factory.

TARNOS .. 5 kms north of the BAYONNE -ANGLET - BIARRITZ district - Accessby train (BAYONNE station), by plane(BIARRITZ-PARME airport), by road(A63 highway, exit 7: ONDRES -TARNOS).

Address .... TURBOMECA - 40220 TARNOSFRANCE

Telephone (33) 5 59 74 40 07 or 05 59 74 40 07

Fax ............ (33) 5 59 74 45 16 or 05 59 74 45 16

E-mail ....... [email protected]

Web site ... w w w . t u r b o m e c a - s u p p o r t . c o m"T.O.O.L.S." (Turbomeca Operator On-Line Support).

The training centre is organized in order to answer totraining demands (administration, training aids,instructors).

Training sites

Training courses are also conducted in subsidiaries, inapproved training centres and on site:- by a TURBOMECA qualified instructor, in certain

subsidiaries and approved training centres- or by an instructor detached from TURBOMECA France,

in our subsidiaries and in the clients' premises.

1.3INTRODUCTION

ARRIUS 1


Training Notes

GENERAL INFORMATION

PARIS

TARNOS

BORDES

SPAIN

FRANCE

BAYONNE

ATLANTIC

OCEAN

TRAININGOBJECTIVES OF TRAINING

TRAINING APPROACH

«The power of knowledge»

Adequate training is essential for obvious safety reasons, but also to reduce additional

maintenance costs incurred by unjustified removals and excessive downtime.

"Greater knowledge leads to greater efficiency".

TRAINING SITES

Training courses are alsoconducted in subsidiaries, in

approved training centres and on site.

TRAINING CENTRE,TURBOMECA Tarnos

(FRANCE)

1.4INTRODUCTION


ARRIUS 1

Edition: May 2006

Training Notes

TRAINING METHOD

Knowledge transmission process

The required knowledge is transmitted in such a mannerthat the student may use it efficiently in various circum-stances.

The training is conducted in accordance with a processwhich considers:

- A phase of explanation for understanding

- A phase of assimilation leading to the complete acqui-sition and long-term retention of the knowledge.

Continuous checking of knowledge helps to ensure theinformation is assimilated. It is more a method of workthan a testing in the traditional sense (refer to chapter 16).

Training method

The training method is a carefully balanced combinationof:

- Lecture

- Exercises

- Discussions

- Practical work.

1.5INTRODUCTION

ARRIUS 1


Training Notes

TRAINING METHOD

1

4 3

2

KNOWLEDGETRANSMISSION PROCESS

TRAINING METHOD

1 - LECTURE

2 - EXERCISES

3 - DISCUSSIONS

4 - PRACTICAL WORK

INSTRUCTOR

MEDIA

STUDENT

EXPLANATION ASSIMILATION

KNOWLEDGE TRANSMISSION,PHASES:

- Explanation

- Assimilation

CHECKING OF KNOWLEDGE:

- Continuous checking, treated in chapter 16

1.6INTRODUCTION


ARRIUS 1

Edition: May 2006

Training Notes

TRAINING AIDS

The acquisition of TURBOMECA training aids does notconstitute proof of official formal training.

Only completion of a course delivered by a TURBOMECAqualified instructor can lead to the issuance of aTURBOMECA recognized training course certificate, stat-ing when applicable a successful result.

The information contained in the training aids is in-tended for training purposes only. It is not a substitutefor the official TURBOMECA maintenance technicalpublications.

Refer to the approved and current TURBOMECAmaintenance technical publications to carry out anymaintenance procedure.

Training notes

The training notes are the basic source of information.

They contain, in a teaching form, all required informationand explanations based on the layout specified in standardATA 104. Each subject is thus dealt with according to aplan which allows the information to be adapted to differ-ent levels of training:

- General (function, position, main characteristics, maincomponents)

- Description (general and detailed)

- Operation (phases, synthesis).

Other technical publications are also used during a course.

Computer Aided Presentation

Computer Aided Presentation consists of a file whichallows the illustrations contained in the training notes tobe projected via a computer.

The Computer Aided Presentation replaces the transpar-encies which were used before to display these sameillustrations

Multimedia courseware

The multimedia courseware is Computer based Trainingsoftware following the training notes layout. It givesinformation in a teaching and interactive manner.

This multimedia system uses text, photos, illustrations,sounds, animation and video. Questionnaires are also usedfor check-up of knowledge.

It forms the essential support of training courses andensures their uniformity.

This system with quick and easy access can be very usefulfor maintaining knowledge levels.

Note: The multimedia courseware and the ComputerAided Presentation are available on CD-ROM.

Demonstration mock-ups

Demonstration mock-ups are also used for componentidentification and maintenance procedures.

1.7INTRODUCTION

ARRIUS 1


Training Notes

MULTIMEDIACOURSEWARE

DEMONSTRATIONMOCK-UPS

COMPUTER AIDEDPRESENTATION

TRAININGNOTES

TRAINING AIDS

The acquisition of TURBOMECA training aids does not constitute proof of official formal training.

Only completion of a course delivered by a TURBOMECA qualified instructor can lead to the issuanceof a TURBOMECA recognized training course certificate, stating when applicable a successful result.

The information contained in the training aids is intended for training purposes only. It is not asubstitute for the official TURBOMECA maintenance technical publications.

Refer to the approved and current TURBOMECA maintenance technical publications to carry outany maintenance procedure.

1.8INTRODUCTION


ARRIUS 1

Edition: May 2006

Training Notes

Examples of programme:

The following pages provide examples of training pro-gramme:

- Familiarization course

- 1st line maintenance (O level): preventive and correctivemaintenance

- 2nd line maintenance (I level): modules, SRU

- 3rd line maintenance (H level): deep maintenance

- Refresher

- Trouble shooting

- Fuel and control system

- Engine documentation.

TRAINING PROGRAMME

The course programme is established to meet trainingrequirements and takes into consideration ATA 104specifications.

It should be noted that the "classroom sessions" alternatewith periods devoted to demonstrations, practical exercisesand visits.

1.9INTRODUCTION

ARRIUS 1


Training Notes

FAMILIARIZATION COURSE

Objective: At the end of this course, the student will be able to describe the engine, to explain its principle of operationand to identify the main components of the engine and systems.

Programme:

- Engine systems (continued)

- Main aspects of maintenance

- Revision - Checking of knowledge

FIRST DAY

SECOND DAY

- Introduction

- General presentation of the engine

- Engine description

- Engine systems

1.10INTRODUCTION


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Edition: May 2006

Training Notes

1st LINE MAINTENANCE COURSE (O LEVEL): PREVENTIVE AND CORRECTIVE MAINTENANCE

Objective: At the end of this course, the student will be able to identify the engine components, to describe and toexplain the operation of the engine and its systems, to carry out maintenance procedures (engine installedin the airframe) and trouble shooting.

Programme:

FIRST DAY

SECOND DAY

THIRD DAY

FOURTH DAY

FIFTH DAY

- Introduction - General

- Engine presentation - Engine description - Oil system - Air system

- Fuel system - Control system - Indication - Starting

- Electrical system

- Engine installation - Operating limitations and procedures

- Various aspects of maintenance - Pratical work

- Pratical work

- Trouble shooting

- Visits - Revision

- Examination - Course conclusion

1.11INTRODUCTION

ARRIUS 1


Training Notes

- Introduction

- Revision (if this course is not conducted directly after the 1st linecourse)

- Removal of modules

- Inspection and check of modules

- Installation of modules

- Inspection and checks after installation

FIRST DAY

SECOND DAY

2nd LINE MAINTENANCE COURSE (I LEVEL): MODULES, SRU

Objective: At the end of this course, the student will be able to identify the engine components, to carry out all themaintenance procedures (engine removed from the airframe), mainly the removal/installation of modulesand shop replaceable units.

Programme: The programme mainly includes practical work. This programme can be carried out after the 1st linemaintenance programme.

1.12INTRODUCTION


ARRIUS 1

Edition: May 2006

Training Notes

3rd LINE MAINTENANCE COURSE (H LEVEL): DEEP MAINTENANCE

Objective: At the end of the course, the trainee will be able to carry out the intramodular maintenance procedures(deep maintenance).

Programme: This course consists entirely of pratical work and the students must have certain qualifications. Thecourse documentation consists of Maintenance Technical Instructions and the Maintenance Manual.

The qualification awarded at the end of this course has certain limits and requires regular renewal.

- Introduction

- Definition of procedures

- Practical work

FROM 3 DAYS TO 3 WEEKS

1.13INTRODUCTION

ARRIUS 1


Training Notes

REFRESHER

Objective: At the end of this course, the trainee will have a greater understanding of the engine and its systems.

Programme:

Note: This course is recommended for technicians who have attended the first line maintenance course, afterabout one year of experience on the engine type.

TROUBLE SHOOTING

Objective: At the end of this course, the trainee will be able to better identify and correct operating problems.

Programme:


- Introduction- Revision of the 1st line maintenance course

- Revision (continued)- Fleet situation - Engine evolution - Course conclusion

FIRST DAY

SECOND DAY

- Introduction- Revision of all engine systems

- Fault finding and rectification- Fleet situation - Engine evolution - Course conclusion

FIRST DAY

SECOND DAY

1.14INTRODUCTION


ARRIUS 1

Edition: May 2006

Training Notes

FUEL AND CONTROL SYSTEM

Objective: At the end of this course, the trainee will have an in-depth understanding of the engine fuel and controlsystems.

Programme:


ENGINE DOCUMENTATION

Objective: At the end of this course, the trainee will be able to understand and use the engine documentation.

Programme:

Note: A general knowledge of engines is recommended.

- Introduction- Fuel and control systems

- Measurement and indicating systems- Engine evolution - Course conclusion

FIRST DAY

SECOND DAY

- Introduction- Presentation of the engine documentation

- Exercises- Course conclusion

FIRST DAY

SECOND DAY

2.1POWER PLANT

ARRIUS 1


Training Notes

2 - POWER PLANT

- Power plant ............................................................ 2.2

• General ................................................................ 2.2

• Description........................................................... 2.4

• Operation ............................................................ 2.6

- Principle of adaptation to the helicopter ............. 2.10

- Main characteristics ............................................. 2.12

- Design and development ....................................... 2.18 to 2.21

2.2POWER PLANT


ARRIUS 1

Edition: May 2006

Training Notes

POWER PLANT - GENERAL

Function

The power plant provides power by transforming theenergy contained in the air and fuel into shaft power.

Main characteristics

- Type: free turbine turboshaft engine with integralreduction gearbox and front power drive

- Concept: modular

- Power: 350 kW class (470 Shp)

- Output shaft rotation speed: 6016 RPM (100% N2)

- Mass dry (with DCU and specific equipment): approx.111.5 kg (246 lbs)

Note: Specific equipment: air inlet guard, exhaust pipeand DCU.

Main components

- Turboshaft engine with specific equipment

- Digital Control Unit (DCU).

2.3POWER PLANT

ARRIUS 1


Training Notes

POWER PLANT - GENERAL

DIGITALCONTROL UNIT

(DCU)

GAS

AIRAIR

AIRAIR

GAS

Power:350 kW class (470 Shp)

Output shaft rotation speed:6016 RPM (at 100% N2)

POWER PLANT

Type:Free turbine turboshaft enginewith integral reduction gearbox

and front power drive

Concept:Modular

Mass dry:111.5 kg (246 lbs)

with "specific equipment"

POWER FUELFUEL

2.4POWER PLANT


ARRIUS 1

Edition: May 2006

Training Notes

POWER PLANT - ENGINE DESCRIPTION

This description considers the engine main functionalcomponents.

Reduction gearbox

- Reduction gear train and main power drive

- Accessory drive train.

Gas generator

- Annular air intake

- Single stage centrifugal compressor

- Reverse flow annular combustion chamber

- Single stage axial turbine.

Power turbine

- Single stage axial turbine

- Co-axial transmission shaft, housed in the gas generatorshaft.

Exhaust pipe

- Exhaust pipe mounted on the turbine casing flange.

2.5POWER PLANT

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Training Notes

POWER PLANT - ENGINE DESCRIPTION

AIRINTAKE

CENTRIFUGALCOMPRESSOR

COMBUSTIONCHAMBER

TURBINE

REDUCTION GEARBOX

ACCESSORYDRIVE TRAIN

REDUCTIONGEAR TRAIN

MAINPOWER DRIVE

GAS GENERATOR

EXHAUSTPIPE

POWER TURBINE

2.6POWER PLANT


ARRIUS 1

Edition: May 2006

Training Notes

POWER PLANT - OPERATION

This part deals with the basic operation of the engine.

Reduction gearbox

- The reduction gear train provides a reduced speed outputfor the main power drive

- The accessory drive train drives the various engineaccessories.

Gas generator

- Admission of the air through the air intake

- Compression of the air in the centrifugal compressor

- Combustion of the fuel/air mixture in a reverse flowannular combustion chamber

- Gas expansion in the single stage axial turbine to drivethe centrifugal compressor and the various engineaccessories.

Power turbine

- Gas expansion in the single stage power turbine to drive

the main power drive through the reduction gear train.

Digital Control Unit

- Control and monitoring of the engine operation.

2.7POWER PLANT

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Training Notes

POWER PLANT - OPERATION

AIR ADMISSION

GAS GENERATOR

COMPRESSION COMBUSTION EXPANSION

REDUCTION GEARBOX

ACCESSORYDRIVE

POWERDRIVE

EXPANSION

POWER TURBINE

FUEL

DIGITAL CONTROL UNIT(engine control and monitoring)

AIR

GAS

2.8POWER PLANT


ARRIUS 1

Edition: May 2006

Training Notes

POWER PLANT - OPERATION -ADAPTATION

This part deals with the parameters and the adaptation ofthe gas generator and power turbine functional assemblies.

Component adaptation

For the engine operation, two functional assemblies can beconsidered:

- The gas generator which provides kinetic energy

- The power turbine which transforms this kinetic energyinto mechanical power on a shaft.

The two assemblies have different rotation speeds.

Gas generator

The gas generator operation is defined by:

- The air mass flow G (air flow which enters the engine)

- The air pressure P3 and air temperature t3 at thecentrifugal compressor outlet

- The fuel flow Q injected into the combustion chamber

- The gas temperature TET at the turbine entry

- The rotation speed N1 of the gas generator

- The kinetic energy Ec supplied to the power turbine.

Power turbine

The power turbine operation is defined by the balancebetween the power received from the gas generator and thetorque applied on the shaft; that is: the torque C and therotation speed N2.

Operation

The operation is represented by the diagram below whichshows the power W, the rotation speeds N1 and N2 and themax. torque limit C imposed by the mechanicaltransmission.

- The torque C is a function of the N2 rotation speed (thetorque is an inverse function of the speed)

- The power W is equal to the torque C multiplied by theangular velocity ω.

- At constant N2 speed, the power is only a function of thetorque

- The engine parameters can be represented as a functionof a reference parameter; N1 for example.

2.9POWER PLANT

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Training Notes

POWER PLANT - OPERATION - ADAPTATION

G(air mass

flow)

N1(rotation speed)

N2(constant rotation speed)

C(shaft torque)

Q(fuel flow)

TET(turbine entrytemperature)

P3, t3(compressor outlet

pressure and temperature)

Ec(kineticenergy)

W(shaft power)

GAS GENERATOR POWER TURBINE

ENGINEPARAMETERS

Power W and speeds N1, N2 P3/P0: Compression ratioCH: Hourly fuel consumption

SFC : Specific fuel consumption

Torque C as a function of N2

Max. torq

ueIsospeeds

N1

W

N2

C

N2 N1

G

P3/P0

WCH

TET

SFC

W = C .

= 2 N60

2.10POWER PLANT


ARRIUS 1

Edition: May 2006

Training Notes

PRINCIPLE OF ADAPTATION TO THEHELICOPTER

Power transmission

The mechanical power supplied by the engine, is used todrive the helicopter rotors through a mechanicaltransmission.

This power drives:

- The main rotor (approximately 82%)

- The tail rotor (approximately 10%)

- The main gearbox (approximately 8%).

Power plant installation (twin-engineconfiguration)

The engines are installed at the rear of the main gearbox.

The power turbines of the two engines are mechanicallyconnected to the main gearbox which drives the rotors(main and tail rotors).

Installation requirements

The main functional requirements of the installation are:

- Constant rotation speed NR in all operating conditions

- Max. torque limit C (usually imposed by the mechanicaltransmission)

- Complete engine protection (against N2 overspeed,TET overtemperature, compressor surge, flame-out...)

- Good load sharing in twin-engine configuration.

Adaptation to requirements

To have a constant rotation speed of the power turbine N2,the power supplied by the engine is automatically adaptedto the needs. This adaptation is ensured by the controlsystem which meters the fuel flow injected into thecombustion chamber so as to deliver the required power(variation of the gas generator N1 rotation speed) whilekeeping the engine within its operational limits.

2.11POWER PLANT

ARRIUS 1


Training Notes

PRINCIPLE OF ADAPTATION TO THE HELICOPTER

N2

∆N2

∆N2

∆W

∆t

ADAPTATION TO REQUIREMENTS

MAIN GEARBOX 8%

MAIN ROTOR82%

TAIL ROTOR10%

POWER TRANSMISSION TWIN-ENGINE CONFIGURATION

MAIN ROTOR

TAILROTOR

Power - W

INSTALLATION REQUIREMENTS

Max. torque(C)

NR

N1, N2, TET...

Time

ENGINE100%

ENGINE

ENGINE 2

ENGINE 1

MAINGEARBOX

2.12POWER PLANT


ARRIUS 1

Edition: May 2006

Training Notes

MAIN CHARACTERISTICS (1)

Engine ratings

The operational ratings correspond to given conditions ofhelicopter operation. The ratings are generally definedunder determined speed and atmosphere conditions(altitude and temperature).

The following operational ratings are considered:

- AEO ratings (All Engines Operating):• Max. Take-Off Power (MTOP): max. rating which

can be used during take-off. This rating has a limitedduration (5 minutes continuous)

• Max. Continuous Power (MCP): rating which can beused without time limitation (this does not imply thatit is used continuously)

- OEI ratings (One Engine Inoperative)• OEI 2 min. 30 sec. (Max. Contingency Power):

rating which can be used in the case of one enginefailure during take-off or landing. This rating isusually limited to a period of continuous operation (2minutes 30 seconds, 15 minutes max. cumulated)

• OEI 30 min. (Intermediate Contingency Power):rating which can be used in the case of one enginefailure in flight. This rating is usually limited to 30minutes.

Note: The power indicated corresponds to the followingconfiguration: engine installed, max. torque in thecorresponding rating, ISA conditions at sea level.

2.13POWER PLANT

ARRIUS 1


Training Notes

ENGINE RATINGS


O.E.I. RATINGSW

A.E.O. RATINGS

MTOP5 min.

MCPContinuous

OEI2 min. 30 sec. OEI

30 min.

2.14POWER PLANT


ARRIUS 1

Edition: May 2006

Training Notes


Operational performance

The values given are min. performance in determinedconditions:

- ISA condition, sea level

- No air bleed

- On test bench with no air intake and exhaust losses

- Under specified N1 speeds (those corresponding to theratings).

Power (W): power available on the engine output shaftconsidering the corresponding torque limitation. It isexpressed in kilowatt (kW) or Shaft horse power (Shp).

Fuel consumption (CH): fuel quantity consumed in oneunit of time; expressed in kilogrammes per hour (kg/hr).

Specific fuel consumption (SFC): fuel quantity required toproduce one unit of power per unit of time: SFC = CH/W;expressed in grammes per kilowatt per hour (g/kW.hr)

2.15POWER PLANT

ARRIUS 1


Training Notes

OPERATIONAL PERFORMANCE


For the 1M and 1E versions, refer to the maintenance manual

Power

< 390 g/kW.h at 221 kW(0.640 lb/HP.hr at 296 Shp)

RatingsSpecific fuel consumption SFC

Max. N1 rotationspeed in RPM

MTOP (5 min.) *

MCP

kW Shp

ARRIUS 1A: example of values

388

357

340

296

520

478

456

397

N1: 54117 RPM (100%).N2: 45438 RPM (100%) 1M/1A/1E*: The N1 speed of the Max. Take-Off Power (calculated as a function of the ambient pressure and temperature) corresponds to the "0" of the N1 difference indicator (∆N1 indicator).

The power indicated corresponds to the following configuration: ISA conditions, Z=0, on test bed or bench

56119

55307

54658

53305

103.7%

102.2%

101%

98.5%

OEI2 min. 30 sec.

OEI30 min.

2.16POWER PLANT


ARRIUS 1

Edition: May 2006

Training Notes


Engine operating envelope

The engine is designed to operate within a given climaticenvelope.

The envelope is defined by:

- The atmospheric temperature t0

- The pressure altitude Zp

- And lines of standard atmosphere.

Flight envelope

The flight envelope is illustrated by the t0/Zp diagram andthe lines of standard atmosphere, with the max. tropicalzone and the min. arctic zone.

Engine starting and relight envelope

The starting and relight envelope is defined in the sameway, but it is also affected by the specifications of oil andfuel used, and sometimes by particular instructions.

Limitations

The engine operates within various limits: rotation speeds,temperatures, pressures…

Refer to corresponding chapters and official publications.

2.17POWER PLANT

ARRIUS 1


Training Notes

ENGINE OPERATING ENVELOPE


6100 m(20000 ft)

+50°C(+122 °F)

5000 m(16400 ft)

+50°C(+122°F)

-50°C(-89.6°F)

-20°C(-4°F)

-500 m(-1640 ft) -50°C

(-89.6 F)

-500 m(-1640 ft)

0 m (0 ft) 0 m (0 ft)

ALTITUDE Zp

TEMPERATUREt0

MA

X. TR

OP

ICA

L

STA

ND

AR

D A

TMO

SP

HE

RE

AR

TIC

NORMALENVELOPE

ENVELOPEENLARGEMENT

WITH PARTICULARINSTRUCTIONS

FLIGHT ENVELOPE ENGINE STARTING ANDRELIGHT ENVELOPE

STARTINGLIMIT

ALTITUDE Zp

TEMPERATUREt0

MIN

.

2.18POWER PLANT


ARRIUS 1

Edition: May 2006

Training Notes

DESIGN AND DEVELOPMENT (1)

Design principles

The engine is designed to meet the aircraft propulsionrequirements and particularly for the new generation ofhelicopters.

The engine design is based on:

- An optimised thermodynamic cycle which allows highperformance

- Simple and reliable components giving a goodsupportability, and a good maintainability to reduce thecosts.

Engine development

The ARRIUS 1 engine is based on the research andexperience of other engines:

- First generation engines: ASTAZOU, ARTOUSTE andTURMO

- Second generation engines: ARRIEL, MAKILA

- New generation engines: ARRIUS, TM 333, MTR 390and RTM 322.

Development steps

The main steps of engine development are:

- September 1981: launch

- 1983: pre-qualification tests (50 h)

- May 1983: first flight

- December 1987: D.G.A.C. certification.

Engine designation

ARRIUS - According to Turbomeca tradition: name of aPyrenean lake.

- 1: Type

- A: Variant

- 1: Version

2.19POWER PLANT

ARRIUS 1


Training Notes


19831st Flight

ARRIUS450 Shp

TM 333850 Shp

MTR 3901200 Shp

RTM 3222100 Shp

ARRIEL650 - 700 Shp

MAKILA1700 - 1800 Shp

ASTAZOU500 - 1000 Shp

TURMO1500 - 1600 Shp

ARTOUSTE400 - 850 Shp

STEPS

TIME

1987D.G.A.C.

certification

1981Launching

DEVELOPMENT STEPS ENGINE DESIGNATION

ENGINE DEVELOPMENT

Optimised thermodynamiccycle

Simple and reliablecomponents

SupportabilityMaintainability

Cost reductionHigh performance

DESIGN PRINCIPLES

Engine design

Example: ARRIUS 1A1ARRIUS: Pyrenean lake

1: TypeA: Variant1: Version

ARRIUS lake

2.20POWER PLANT


ARRIUS 1

Edition: May 2006

Training Notes


Application

The ARRIUS 1 engine is designed for the followingapplications:

- Twin engine AS 355 Ecureuil: ARRIUS 1A-E

- Twin engine AS 555 Fennec: ARRIUS 1M.

Maintenance concept

The ARRIUS 1 is designed to provide a high availabilityrate with reduced maintenance costs.

The main aspects of the maintenance concept are thefollowing:

- Full modularity

- Good accessibility

- Reduced removal and installation times

- "On condition" monitoring

- High initial TBO

- Low cost of ownership:• Low production costs• Durability (defined and proven TBO and life limits)• High reliability• Low fuel consumption.

Engine fleet status

In ......, we can note:

- Number of engines produced: ...

- Operating hours: ...

2.21POWER PLANT

ARRIUS 1


Training Notes


MAINTENANCE CONCEPT

- Full modularity- Good accessibility- Reduced removal and installation times- "On condition" monitoring- High initial TBO- Low cost of ownership:

• Low production costs• Durability (defined and proven TBO

and life limits)• High reliability• Low fuel consumption.

FLEET STATUS

- Number of engines produced- ARRIUS 1 operating hours

Twin engine AS 355 Squirrel Twin engine AS 555 Fennec

Arrius 1A - E Arrius 1M

3.1ENGINE

ARRIUS 1


Training Notes

3 - ENGINE

- Engine ..................................................................... 3.2

- Air intake (72-42-10 and 75-30-01) ..................... 3.8

- Compressor (72-42-20) ......................................... 3.10

- Combustion chamber (72-42-40) .......................... 3.16

- Gas generator turbine (72-42-30) ......................... 3.22

- Power turbine (72-42-50) ..................................... 3.28

- Exhaust system (78-10-01) .................................... 3.34

- Reduction gearbox (72-11-10) .............................. 3.38

• Reduction gear train (72-11-10) ...................... 3.40

• Accessory drive train (72-11-20) ..................... 3.46 to 3.51

(XX-XX-XX): Page references which deal with the subject in the maintenance documentation.

3.2ENGINE


ARRIUS 1

Edition: May 2006

Training Notes

ENGINE - GENERAL

Function

The engine transforms the energy in the fuel and air intomechanical power on a shaft.


- Type: free turbine, integral reduction gearbox and frontpower drive

- Gas generator rotation speed N1: 54117 RPM (100%)• Direction of rotation: anti-clockwise (ACW)

- Power turbine rotation speed N2: 45438 RPM (100%)• Direction of rotation: clockwise (CW)

- Power drive rotation speed: 6016 RPM (100% N2)• Direction of rotation: clockwise (CW).

Note: Direction of rotation given viewed from the rear.

Main components

- Reduction gearbox (reduction gear train and accessorydrive train)

- Gas generator (air intake, centrifugal compressor,combustion chamber, turbine)

- Power turbine.

3.3ENGINE

ARRIUS 1


Training Notes

ENGINE - GENERAL

TypeFree turbine, integral reductiongearbox and front power drive

Gas generator (N1)54117 RPM (100%) - ACW

Power turbine (N2)45438 RPM (100%) - CW

Output shaft6016 RPM (100% N2) - CW

POWERTURBINE

TURBINECENTRIFUGALCOMPRESSOR

COMBUSTIONCHAMBER

REDUCTIONGEAR TRAIN

AIRINTAKE


3.4ENGINE


ARRIUS 1

Edition: May 2006

Training Notes

ENGINE - DESCRIPTION

Main functional components

- Reduction gearbox• Reduction gear train• Accessory drive train

- Gas generator• Annular air intake• Single stage centrifugal compressor• Annular, reverse flow combustion chamber• Single stage axial turbine

- Power turbine• Single stage axial turbine• Coaxial transmission shaft.

Modular layout

The engine comprises 2 modules:

- Module M01: Reduction gear train and accessory drivetrain

- Module M02: Gas generator (air intake, centrifugalcompressor, combustion chamber and turbine) and powerturbine.

Note 1: A module is a sub-assembly which can bereplaced on-site (2nd line maintenance) withoutcomplex tooling or adaptation work.

Each module has an identification plate. Theengine identification plate is fitted on the face ofthe reduction gearbox casing.

Note 2: Some accessories are provided with eachmodule.

In these training notes, those components aredealt with in the chapters corresponding to themain systems.

3.5ENGINE

ARRIUS 1


Training Notes

ENGINE - DESCRIPTION

M01 MODULEREDUCTION GEARBOX

M02 MODULEGAS GENERATOR AND POWER TURBINE

M01 moduleidentification

plate

Engineidentification

plate

M02 moduleidentification

plate

3.6ENGINE


ARRIUS 1

Edition: May 2006

Training Notes

ENGINE - OPERATION

The process comprises admission, compression,combustion, expansion and power transmission.

Compression

The ambient air is compressed by a single stage centrifugalcompressor.

This phase is essentially characterised by the air flow(1.6 kg/s; 3.5 lbs/sec.) and the compression ratio (approx.8.5).

Combustion

The compressed air is admitted into the combustionchamber, mixed with the fuel and burnt in a continuousprocess.

The air is divided into two flows:

- A primary air flow for combustion

- A secondary air flow for the cooling of the gas.

This phase is essentially characterised by the temperaturerise (flame temperature approx. 2500°C; 4530°F) and apressure drop of about 4%.

Expansion

- In the gas generator turbine which extracts the energyrequired to drive the compressor (N1 speed: 54117 RPMat 100%, ACW).

During this phase, the gas pressure and temperature dropwhilst the velocity increases

- In the power turbine which extracts most of the remainingenergy to drive the power drive through the reductiongearbox (N2 speed: 45438 RPM at 100%, CW).

After the expansion through the power turbine, the gasare discharged overboard through an outlet diffuser anda divergent exhaust pipe. The expansion phase goes onand the gas are expelled overboard with a slight residualforward thrust.

Note: The engine reference stations are:1 - Ambient air2 - Compressor inlet3 - Compressor outlet4 - Gas generator turbine inlet

4.5 - Gas generator turbine outlet5 - Power turbine outlet.

3.7ENGINE

ARRIUS 1


Training Notes

ENGINE - OPERATION

4.54 5

P kPa(PSI)

T°C(°F)

15

320

(59)

(608)

321

101.3

861826.5

1000230

(14.6)

(125)

(1832)

(120)

(33.3)

800(1472)

100

(14.5)

Gas generator54117 RPM (100%) - ACW

FUELAMBIENT AIR

1.6 kg/s(3.5 lbs/sec.)

Power turbine45438 RPM (100%) - CW

Residual thrust

ROTATION SPEED

EXHAUST

2500°C (4532°F)

Primary air(combustion air)

Secondary air(dilution air)

Gas

Values given forinformation at a

given reference rating

ADMISSION

CompressorCombustion

chamber Turbines

EXPANSIONCOMBUSTIONCOMPRESSION

Exhaust

3.8ENGINE


ARRIUS 1

Edition: May 2006

Training Notes

AIR INTAKE

Function

The air intake directs the ambient air into the centrifugalcompressor.

Position

- At the front of the centrifugal compressor.


- Type: annular

- Air flow: 1.6 kg/s (3.5 lbs/sec.).

Description

The air intake includes the following components:

- Air intake casing. It is made of aluminium alloy. It isannular with a parallel passage. It is secured by a ring ofbolts to the rear casing of the reduction gearbox at thefront and to the centrifugal compressor front cover andthe intermediate casing at the rear. The internal hub ofthe air intake casing, which is supported by four struts,houses the gas generator front bearing

- Air intake guard. It is made of two half screens. One ofthem has an orifice for borescopic inspection. It issecured around the air intake casing.

- Compressor washing device (optional). The washingdevice comprises a supply union, an internal duct and ajet to spray the washing product.

Operation

The ambient air is admitted through the aircraft air intakeduct, the plenum, the intake guard and the engine airintake.

If the intake guard becomes obstructed the air can passthrough the inner part of the guard as a "by-pass".

3.9ENGINE

ARRIUS 1


Training Notes

AIR INTAKE

TypeAnnular

Air flow1.6 kg/s (3.5 lbs/sec.)

NORMALSUPPLY

BY-PASSSUPPLY

ENGINE AIRINTAKE CASING

STREAMLINEDSTRUT

FRONTBEARING

AIR INTAKEGUARD

MOUNTING FLANGE(on air intake casing)

10 mm ORIFICE(compressor washing -borescopic inspection)

COMPRESSORWASHING DEVICE

(optional)

SUPPLYUNION

AIR INTAKEGUARD

3.10ENGINE


ARRIUS 1

Edition: May 2006

Training Notes

COMPRESSOR - GENERAL

Function

The centrifugal compressor provides the compressed airrequired for combustion.

Position

- At the rear of the air intake casing.


- Type: centrifugal, single stage

- Overall compression ratio: approx. 8.5

- Rotation speed: N1; ACW.

Main components

- Rotating component (centrifugal wheel)

- Stationary components (diffuser assembly, front cover,intermediate casing).

3.11ENGINE

ARRIUS 1


Training Notes

COMPRESSOR - GENERAL

TypeCentrifugal, single stage

Overall compressionratio

approx. 8.5

Rotation speedN1; ACW

CENTRIFUGALWHEEL

INTERMEDIATECASING

FRONTCOVER

DIFFUSERASSEMBLY

3.12ENGINE


ARRIUS 1

Edition: May 2006

Training Notes

COMPRESSOR - DESCRIPTION

The centrifugal compressor assembly includes rotatingand stationary components.

Rotating components

The main rotating component is the centrifugal impeller.The wheel has blades which are cut from the solid in a discof titanium alloy.

The rear part has a curvic-coupling for the connection tothe gas generator turbine.

The wheel is mounted on the gas generator shaft.

Stationary components

The stationary assembly includes the casings and thediffuser assembly.

The compressor front cover houses the centrifugalcompressor and is provided with an abradable coatingwhich gives a reduced clearance. The cover fits into the airintake casing. It is bolted to the intermediate casing bymeans of a ring of bolts.

The diffuser assembly comprises the first stage diffuserformed by radial stator vanes and the second stage diffuserformed by axial stator vanes. The rear cover of the diffuserassembly separates the compressor from the combustionchamber. It is bolted to the intermediate casing by a ring ofbolts.

The intermediate casing ensures the mechanicalconnection between the air intake casing and the externalcasing.

3.13ENGINE

ARRIUS 1


Training Notes

COMPRESSOR - DESCRIPTION

AIR INTAKECASING

INTERMEDIATECASING

CENTRIFUGAL IMPELLER(titanium impeller with

blades cut from the solid)

DIFFUSERASSEMBLY

CURVIC-COUPLING

FRONT COVER(provided with an

abradable coating)

GAS GENERATORSHAFT

REARCOVER

INTERMEDIATECASING

AIR INTAKECASING

FRONTCOVER

DIFFUSERASSEMBLY

CENTRIFUGALIMPELLER

3.14ENGINE


ARRIUS 1

Edition: May 2006

Training Notes

COMPRESSOR - OPERATION

The compressor ensures the compression stage.

Compressor air flow

The air from the air intake flows into the centrifugalcompressor.

The air flows between the blades of the centrifugalcompressor. The air pressure increases due to the divergentpassage between the blades and the air velocity increasesdue to the centrifugal flow.

The air leaves the tips of the blades at a very high velocityand then flows through the first stage diffuser vanes wherethe velocity reduces and the pressure increases.

The air then passes through an elbow and the flow becomesaxial. In the second stage diffuser, the velocity is againreduced and the pressure increased. This air is then admittedinto the combustion chamber.

3.15ENGINE

ARRIUS 1


Training Notes

COMPRESSOR - OPERATION

AIR STRAIGHTENINGAND COMPRESSION

AIR ADMISSION

AIR ACCELERATIONAND COMPRESSION

AIR ADMITTED INTOTHE COMBUSTION CHAMBER

3.16ENGINE


ARRIUS 1

Edition: May 2006

Training Notes

COMBUSTION CHAMBER - GENERAL

Function

The combustion chamber burns the fuel/air mixture anddelivers the gas thus generated to the turbine.

Position

- Central section of the gas generator.


- Type: annular, reverse flow

- Overall fuel/air ratio: 1/45.

Main components

- Flame tube

- Inner and outer elbows

- External casing.

3.17ENGINE

ARRIUS 1


Training Notes

COMBUSTION CHAMBER - GENERAL

EXTERNALCASING

TypeAnnular, reverse flow

Overall fuel/air ratio1/45

OUTERELBOW

INNERELBOW

FLAME TUBE

3.18ENGINE


ARRIUS 1

Edition: May 2006

Training Notes

COMBUSTION CHAMBER - DESCRIPTION

The combustion chamber assembly includes the externalcasing, the flame tube, the external and internal elbowsand the fuel injection system.

External casing

This casing houses the combustion chamber. It has bossesfor the mounting of the main injectors, the start injectors,the igniter plugs, the air tappings and the combustionchamber purge valve.

There is also a borescope port for inspection.

The external casing is bolted at the front to the diffuserassembly and to the intermediate casing.

Flame tube

The flame tube is made of special alloy. It forms anenclosure in which the fuel/air mixture is burnt. It hasnumerous calibrated orifices for the passage of air.

The flame tube fits in the outer and inner elbows by slidingcontacts. It is maintained inside the external casing andcentered by the igniter plug housings and two centeringpins.

Note: The calibrated orifices are drilled using the electronbeam process.

Outer elbow

The outer elbow directs the gas to the turbine nozzle guidevane. It is attached to the diffuser holder plate and to thenozzle guide vane of the gas generator turbine.

Inner elbow

The inner elbow is mounted on the turbine nozzle guidevane.

Fuel injection system

- The start fuel injection is ensured by 4 simple injectorslocated on the combustion chamber casing, 2 are closeto the igniter plugs

- The main fuel injection is ensured by nine main injectorsand a "preference" injector, all located on the rear faceof the combustion chamber casing. The injectorspenetrate into T-shaped tubes welded at the rear of theflame tube.

Refer to chapter "FUEL SYSTEM" for more informationabout the fuel injection system.

3.19ENGINE

ARRIUS 1


Training Notes

COMBUSTION CHAMBER - DESCRIPTION

MAININJECTOR

FLAMETUBE

STARTINJECTOR

IGNITERPLUG

VAPORISERTUBE

VAPORISERTUBE

EXTERNALCASING

INNERELBOW

OUTERELBOW

NOZZLE GUIDEVANE

OUTERELBOW

INNERELBOW

(with nozzleguide vane)

FLAMETUBE

3.20ENGINE


ARRIUS 1

Edition: May 2006

Training Notes

COMBUSTION CHAMBER - OPERATION

The combustion chamber forms an enclosure in which thefuel/air mixture is burnt.

Flow in the combustion chamber

In the combustion chamber, the compressed air is dividedinto two flows: a primary air flow mixed with the fuel forcombustion and a secondary air flow (or dilution air flow)for cooling.

Primary air

The primary air flows through the calibrated orifices of theflame tube and through the hollow vanes of the turbinenozzle guide vane (cooling of the vanes).

In the flame tube, the primary air is mixed with the fuelsprayed by the injectors. The combustion occurs inside theflame tube. The flame temperature reaches approx. 2500°C(4530°F).

Secondary air

The secondary air (or dilution air) flows through theorifices of the flame tube. It is calibrated to obtain flamestability, cooling of the gas and an even distribution oftemperature on the turbine.

Gas

The gas flow rearward through the combustion chamberelbow and then through the turbine nozzle guide vane.

3.21ENGINE

ARRIUS 1


Training Notes

COMBUSTION CHAMBER - OPERATION

PRIMARY AIR(combustion)

SECONDARY AIR(dilution)

GAS

FUELINJECTION

GAS DIRECTEDTO THE TURBINE

COMPRESSEDAIR

COMBUSTION2500°C (4530°F)

3.22ENGINE


ARRIUS 1

Edition: May 2006

Training Notes

GAS GENERATOR TURBINE - GENERAL

Function

The turbine extracts sufficient energy from the gas flow todrive the centrifugal compressor and the engine accessories.

Position

- At the rear of the gas generator.


- Type: axial, single stage turbine with uncooled insertedblades

- Rotation speed: N1; ACW.

Main components

- Rotating components (wheel, shaft, bearing)

- Stationary components (nozzle guide vane, intermediatediffuser, containment shield…).

3.23ENGINE

ARRIUS 1


Training Notes

GAS GENERATOR TURBINE - GENERAL

BEARING

SHAFT

CONTAINMENTSHIELD

NOZZLE GUIDEVANE

TypeAxial, single stage turbine

with uncooled inserted blades

Rotation speedN1; ACW

WHEEL

INTERMEDIATEDIFFUSER

3.24ENGINE


ARRIUS 1

Edition: May 2006

Training Notes

GAS GENERATOR TURBINE - DESCRIPTION

The gas generator turbine assembly includes rotating andstationary components.

Rotating components

The main rotating component is the turbine wheel. Thewheel consists of a disc with fir-tree mounted singlecrystal blades.

At the front, the wheel is coupled to the centrifugalcompressor shaft by a curvic-coupling.

The rear part of the gas generator is supported by a rollerbearing.

Rotating labyrinth seals ensure the sealing of the bearing.

A nut at the rear secures the turbine wheel labyrinth andbearing to the gas generator shaft.

A balance piston is located on the front of the turbinewheel.


The main stationary components are the turbine nozzleguide vane, the containment shield and the intermediatediffuser.

The turbine nozzle guide vane includes a row of hollowvanes through which the cooling air flows. It is bolted tothe combustion chamber inner part and to the containmentshield.

The containment shield is located around the turbine wheelto ensure its containment in case of blade failure.

The intermediate diffuser ensures the gas flow from the gasgenerator to the power turbine. Its internal hub houses thegas generator rear bearing. The diffuser also includesstruts which house the lubrication tubes for the rear bearings.

3.25ENGINE

ARRIUS 1


Training Notes

GAS GENERATOR TURBINE - DESCRIPTION

TURBINE WHEEL(inserted blades)

ROLLERBEARING

CONTAINMENTSHIELD

BALANCEPISTON

CURVIC-COUPLING(with compressor)

INTERMEDIATEDIFFUSER

TURBINE NOZZLEGUIDE VANE(hollow vanes)

GAS GENERATORSHAFT

SECURINGNUT

TURBINE BLADE(fir-tree root)

REAR BEARING(roller)

NOZZLEGUIDE VANE

GAS GENERATORSHAFT

LABYRINTHSEAL(rear)

BALANCEPISTON

TURBINEWHEEL

3.26ENGINE


ARRIUS 1

Edition: May 2006

Training Notes

GAS GENERATOR TURBINE - OPERATION

The gas generator turbine transforms the kinetic energycontained in the gas into mechanical power required todrive the compressor and the engine accessories.

Turbine gas flow

The gas from the combustion chamber first flows throughthe nozzle guide vanes. The gas velocity increases due tothe convergent passage.

The flow over the turbine blades results in aerodynamicforces whose resultant causes the rotation of the wheel anddrives the compressor and the engine accessories.

The gas, still containing energy, is directed to the powerturbine through the intermediate diffuser.

3.27ENGINE

ARRIUS 1


Training Notes

GAS GENERATOR TURBINE - OPERATION

COMPRESSOR ANDACCESSORY DRIVE

NOZZLE GUIDEVANE

GAS FROM THECOMBUSTION CHAMBER

TURBINE WHEELROTATION

GAS DIRECTED TOTHE POWER TURBINE

Nozzleguide vane

Turbinewheel

Rotation

3.28ENGINE


ARRIUS 1

Edition: May 2006

Training Notes

POWER TURBINE - GENERAL

Function

The power turbine extracts the energy which remains inthe gas to drive the power drive through the reduction geartrain.

Position

- At the rear of the engine. It belongs to the M02 module.


- Type: axial, single stage, one piece wheel (or disc andfir-tree mounted blades after TU71) mounted on thepower turbine shaft

- Rotation speed: N2; CW.

Main components

- Rotating components (wheel, shaft, bearing)

- Stationary components (nozzle guide vane, containmentshield, casing, internal hub, bearing cage).

3.29ENGINE

ARRIUS 1


Training Notes

POWER TURBINE - GENERAL

TypeAxial, single stage, one piece wheel

(or disc and fir-tree mounted blades after TU71)mounted on the power turbine shaft

Rotation speedN2; CW

WHEEL

POWER TURBINENOZZLE GUIDE VANE

SHAFT

BEARING

INTERNALHUB

BEARINGCAGE

POWER TURBINECASING

CONTAINMENTSHIELD

3.30ENGINE


ARRIUS 1

Edition: May 2006

Training Notes

POWER TURBINE - DESCRIPTION

The power turbine assembly belongs to the M02 module.It includes rotating components and stationary components.

Rotating components

The main rotating component is the turbine wheel. It is aone piece wheel ( or disc and fir-tree mounted blades afterTU71) mounted on the power turbine shaft.

The power turbine shaft is supported by a ball bearing(squeeze film bearing) housed in the intermediate diffuserinternal hub. Rotating labyrinth seals ensure the bearingsealing.

The power turbine shaft passes through the hollow shaft ofthe gas generator. At the front, it has splines for themounting of the reduction gear train drive gear.


The main stationary components are the nozzle guidevane, the containment shield and the casing.

The nozzle guide vane forms a one piece assembly ofvanes located between external and internal rings.

The containment shield is located around the externalring of the nozzle guide vane. It ensures the bladecontainment in case of blade breaking.

The power turbine casing is bolted to the gas generatorexternal casing. It is formed by an outer case and an innercase connected by four hollow struts. Two struts house theoil tubes for the lubrication of the power turbine bearingand the gas generator turbine bearing.

The internal hub supports the bearing cage. The lubricationtubes are screwed into the internal hub. The internal hub issecured at the rear to the power turbine casing.

The bearing cage supports the power turbine ball bearingand the gas generator roller bearing.

3.31ENGINE

ARRIUS 1


Training Notes

POWER TURBINE - DESCRIPTION

INTERNALHUB

INTERNALHUB

BALLBEARING

POWER TURBINESHAFT

BEARINGCAGE

LABYRINTHSEALS

SPLINES(to drive the input gear

of the reduction gear train)

LUBRICATIONTUBE

POWER TURBINENOZZLE GUIDE VANE

CONTAINMENTSHIELD

POWER TURBINECASING

POWER TURBINECASING

POWERTURBINE

TURBINESHAFT

BEARINGCAGE

PHONICWHEEL

POWER TURBINEBEARING

(ball bearing)

SECURING NUT(to secure the bearing

on the shaft)

POWER TURBINEWHEEL

3.32ENGINE


ARRIUS 1

Edition: May 2006

Training Notes

POWER TURBINE - OPERATION

The power turbine transforms the gas energy provided bythe gas generator into mechanical power to drive thepower drive through the reduction gear train.

Power turbine flow

The gas supplied by the gas generator flows first throughthe nozzle guide vane in which the velocity increases dueto the convergent passage.

The gas is directed onto the turbine wheel and the resultantof the aerodynamic forces on the blades causes the wheelto rotate and drive the power drive through the reductiongear train.

The gas is then expelled overboard through the exhaustpipe.

3.33ENGINE

ARRIUS 1


Training Notes

POWER TURBINE - OPERATION

Nozzleguide vane

Turbinewheel

Rotation

GAS FROM THEGAS GENERATOR TURBINE

NOZZLEGUIDE VANE

POWER TURBINEWHEEL ROTATION

GAS EXPELLEDOVERBOARD

REDUCTIONGEAR TRAIN DRIVE

3.34ENGINE


ARRIUS 1

Edition: May 2006

Training Notes

EXHAUST SYSTEM - GENERAL

Function

The exhaust system continues the expansion phase andexpels the gas overboard.

It also ensures the axial containment of the power turbinewheel.

Position

- Behind the power turbine.


- Type: axial, exhaust pipe with extension

- Replaceable non modular component.

Main components

- Exhaust pipe

- Extension

- Mounting clamp (M02 module)

- Heat shield

- Oil system vent pipe

- Central cone.

3.35ENGINE

ARRIUS 1


Training Notes

EXHAUST SYSTEM - GENERAL

EXHAUSTPIPE

EXHAUSTPIPE

OIL SYSTEMVENT PIPE

MOUNTINGCLAMP

(M02 module)

EXTENSION

CENTRALCONE

HEAT SHIELD

TypeAxial, exhaust pipe

with extension

Replaceable nonmodular component

3.36ENGINE


ARRIUS 1

Edition: May 2006

Training Notes

EXHAUST SYSTEM - DESCRIPTION -OPERATION

Description

The main components of the exhaust system are:

The exhaust pipe which is a sheet metal worked assembly.It includes a central cone which improves the gas flow andreduces the residual thrust. The exhaust pipe has bosses forthe drain unions and a boss for the oil system vent pipe.

The venturi extension which increases the cooling airflow through the engine compartment by venturi effect.

The mounting clamp which secures the exhaust pipe tothe turbine casing rear part.

Note: The central cone is design to ensure the axialcontainment of the power turbine wheel.

Operation

The gas are expelled overboard through the divergentpassage of the exhaust diffuser and exhaust pipe. They stillhave a certain amount of energy causing a slight residualthrust.

The exhaust system collects the oil system general air vent.

The gap between the exhaust pipe and the extensionimproves the engine compartment ventilation.

3.37ENGINE

ARRIUS 1


Training Notes

EXHAUST SYSTEM - DESCRIPTION - OPERATION

Oil systemvent pipe

CLAMP

GAS EXHAUST

Engine compartment air suctionby Venturi effect

POWERTURBINE

EXHAUST PIPE EXTENSIONCENTRALCONE

3.38ENGINE


ARRIUS 1

Edition: May 2006

Training Notes

REDUCTION GEARBOX

General

Function

The reduction gearbox drives the main power drive and thevarious accessories required for the engine operation.

Position

- At the front of the engine; it forms the M01 module.


- Casings: light alloy

- Gears: steel• Reduction gear train: helical gears• Accessory drive train: spur gears

- Power drive:• Rotation speed: 6016 RPM (100% N2)• Direction of rotation: CW

Main components

- Front and rear casings

- Reduction gear train

- Accessory drive train

- Accessories installed on the reduction gearbox.

3.39ENGINE

ARRIUS 1


Training Notes

REDUCTION GEARBOX

POWER DRIVE6016 RPM (100% N2) - CW


REDUCTIONGEAR TRAIN

REARCASING

FRONTCASING

CasingsLight alloy

GearsSteel

MANUFACTURINGMATERIALS

3.40ENGINE


ARRIUS 1

Edition: May 2006

Training Notes

REDUCTION GEAR TRAIN - GENERAL

Function

The reduction gear train provides an output drive speed tomeet the drive requirements of the helicopter rotor.

Position

- In the lower part of the reduction gearbox.


- Type: 1 gear train with direct output parallel to theengine axis

- Input gear:• Type: helical gear• Rotation speed: 45438 RPM (100%)

- Double intermediate gear:• Type: helical gears

- Output gear:• Type: helical gear• Rotation speed: 6016 RPM (100%).

Main components

- Input gear

- Double intermediate gear

- Output gear

- Casings.

3.41ENGINE

ARRIUS 1


Training Notes

REDUCTION GEAR TRAIN - GENERAL

Type1 gear train with output

parallel to the engine axis

Input gear rotation speed45438 RPM (100% N2)

Output gear rotation speed6016 RPM (100% N2)

CASINGS

INPUT GEAR

DOUBLE INTERMEDIATEGEAR

OUTPUTGEAR

POWER TURBINESHAFT

3.42ENGINE


ARRIUS 1

Edition: May 2006

Training Notes

REDUCTION GEAR TRAIN - DESCRIPTION

The reduction gear train includes three gears supported byball and roller bearings.

Input gear

The input gear is a simple helical gear directly mounted onthe power turbine shaft by splines. It is supported by tworoller bearings.

Double intermediate gear

The intermediate gear is a double gear. One gear is drivenby the input gear and the other gear drives the output gear.

The intermediate gear is supported by two roller bearings.

The double intermediaire gear houses a hydraulictorquemeter.

Output gear

The output gear is a simple helical gear. The output shaftis fitted with a triangular flange for the adaptation to thehelicopter transmission.

The output gear is supported by a roller bearing at the frontand a ball bearing at the rear.

A graphite seal ensures the sealing of the power drive.

3.43ENGINE

ARRIUS 1


Training Notes

REDUCTION GEAR TRAIN - DESCRIPTION

GRAPHITESEAL

INPUTGEAR

INPUTGEAR

DOUBLEINTERMEDIATE

GEAR

OUTPUTGEAR

POWERDRIVE

HYDRAULICTORQUEMETER

3.44ENGINE


ARRIUS 1

Edition: May 2006

Training Notes

REDUCTION GEAR TRAIN - OPERATION

The reduction gear train provides a forward output drive ata reduced speed to meet the drive requirements of thehelicopter.

It also houses an engine torque measuring system.

Operation of the reduction gear train

The drive gear is driven by the transmission shaft splinesat the power turbine rotation speed (of approx. 45438 RPMat 100 %). It drives the intermediate gear.

The intermediate gear then drives the output gear whichprovides the main power drive at a speed of 6016 RPM.

Operation of the torquemeter

The engine torque measuring system is a hydraulictorquemeter housed in the double intermediate gear.

The system includes the hydraulic torquemeter, thetransmitter and the indicator.

Refer to chapter "MEASUREMENT AND INDICATINGSYSTEMS" for the description and operation of the enginetorque measuring system.

3.45ENGINE

ARRIUS 1


Training Notes

REDUCTION GEAR TRAIN - OPERATION

INPUTGEAR

DOUBLEINTERMEDIATE

GEAR

OUTPUT GEAR6016 RPM - 100% N2 Front face of the reduction gearbox

POWERTURBINE

INPUT GEAR45438 RPM - 100% N2

3.46ENGINE


ARRIUS 1

Edition: May 2006

Training Notes

ACCESSORY DRIVE TRAIN - GENERAL

Function

Driven by the gas generator shaft, the accessory drive trainprovides the mechanical power required to drive the engineaccessories.

Position

- In the upper part of the reduction gearbox.


- Type: spur gear train

- Drive gear rotation speed: 54117 RPM (100 % N1)

Main components

- Accessory drive train

- Casings.

3.47ENGINE

ARRIUS 1


Training Notes

ACCESSORY DRIVE TRAIN - GENERAL

TypeSpur gear train

Drive gear rotation speed54117 RPM (100% N1)


CASINGS

3.48ENGINE


ARRIUS 1

Edition: May 2006

Training Notes

ACCESSORY DRIVE TRAIN - DESCRIPTION

The accessory drive train has 8 spur gears supported byball bearings.

Drive gear

The drive gear is mounted on the gas generator shaft.

- Rotation speed: 54117 RPM (100% N1).

LP fuel pump and alternator gear

It is a double gear.

Intermediate gear (1)


Oil pump gear

It is a single gear.



Starter-generator gear

This gear also incorporates the centrifugal breather and theN1 phonic wheels. It is provided with a magnetic seal.



HP fuel pump gear


3.49ENGINE

ARRIUS 1


Training Notes

ACCESSORY DRIVE TRAIN - DESCRIPTION

INTERMEDIATEGEAR (1)

OIL PUMPGEAR

STARTER-GENERATOR GEAR(centrifugal breather, phonic wheels)




LP FUEL PUMP ANDALTERNATOR GEAR

HP FUELPUMP GEAR

DRIVEGEAR

DRIVE GEAR(54117 RPM)


MAGNETICSEAL

3.50ENGINE


ARRIUS 1

Edition: May 2006

Training Notes

ACCESSORY DRIVE TRAIN - OPERATION

The accessory drive train drives the various accessoriesrequired for the engine operation.

Operation engine running

The drive gear is directly driven by the gas generator shaftat a speed of 54117 RPM (100% N1). It drives the doubleintermediate gear which then drives:

- The oil pump gear through the intermediate gear (3)

- The starter-generator gear through the intermediate gears(2) and (3)

- The HP fuel pump through the intermediate gear (1).

Operation during starting

During starting, the starter motor drives, through theaccessory gear train, the gas generator rotating assembly.

At self-sustaining speed (approximately 50% N1), theelectrical supply to the starter motor is automatically cut.The starter is then driven and operates as an electricalgenerator.

3.51ENGINE

ARRIUS 1


Training Notes

ACCESSORY DRIVE TRAIN - OPERATION

Front face of the reduction gearbox

STARTER-GENERATOR GEAR(centrifugal breather, phonic wheels)

OIL PUMPGEAR




HP FUELPUMP GEAR

DRIVE GEAR54117 RPM(100% N1)


STARTER-GENERATORGEAR

OIL PUMPGEAR


HP FUELPUMP GEAR

GAS GENERATORSHAFT

4.1OIL SYSTEM

ARRIUS 1


Training Notes

4 - OIL SYSTEM- Oil system (79-00-00) ............................................ 4.2- Oil reservoir .......................................................... 4.8- Oil pumps (79-20-01) ............................................ 4.10- Oil filter (79-20-02) ............................................... 4.14- Pre-blockage pressure switch (79-00-00) ............. 4.20- Cooling unit ............................................................ 4.22- Centrifugal breather.............................................. 4.24- Electrical magnetic plugs (79-30-01) .................... 4.26- Strainers (79-30-02) ............................................... 4.28- Low oil pressure switch (79-30-03) ....................... 4.30- Oil pressure transmitter (79-30-04)...................... 4.32- Oil temperature probe ........................................... 4.34- Oil pipes (79-20-03) ................................................ 4.36 to 4.37


4.2OIL SYSTEM


ARRIUS 1

Edition: May 2006

Training Notes

OIL SYSTEM - GENERAL

Function

The oil system ensures lubrication and cooling of theengine. It is also used for the hydraulic torquemeteroperation.

Position

All the system components are fitted on the engine exceptthe cooling unit and the oil reservoir.


- Type: variable pressure, full flow, dry sump system,synthetic oil

- Max. oil temperature: 110°C (230°F)

- Max. oil consumption: 0.3 l/h (0.08 US G/hr)

- Oil pressure: 300 - 400 kPa (43.5 - 58 PSI)

- Low oil pressure warning: 170 kPa (24.6 PSI)

- Max. oil pressure: 1000 kPa (145 PSI)

- Total oil volume: approx. 4.8 litres (1.25 US G).

Lubrication requirements

Lubrication is required for the following components :

- Front bearing

- Rear bearings

- Gears and bearings of the reduction gear train and theaccessory drive train.

Sealing

The gas generator and power turbine bearings are sealedby pressurised labyrinths, which are provided withabradable deposits.

4.3OIL SYSTEM

ARRIUS 1


Training Notes

OIL SYSTEM - GENERAL

Sealing:the gas generator and power turbine bearings are sealed by pressurised labyrinths, which are provided with abradable deposits.

REARBEARINGS

FRONTBEARING

GEARS AND BEARINGSOF THE ACCESSORY

DRIVE TRAIN

GEARS AND BEARINGS OFTHE REDUCTION GEAR TRAIN

TypeVariable pressure, full flow,

dry sump, synthetic oil

Max. oil temperature110°C (230°F)

Max. oil consumption0.3 l/h (0.08 US G/hr)

Oil pressure300 - 400 kPa (43.5 - 58 PSI)

Low oil pressure warning170 kPa (24.6 PSI)

Max. oil pressure1000 kPa (145 PSI)

Total oil volumeapprox. 4.8 litres (1.25 US G)

OIL SYSTEM

ENGINELUBRICATION

TORQUEMETER

ENGINECOOLING

4.4OIL SYSTEM


ARRIUS 1

Edition: May 2006

Training Notes

OIL SYSTEM - DESCRIPTION

The main components of the oil system are:

Oil reservoir

The oil reservoir contains the volume of oil required tolubricate the engine.

It is installed in the aircraft and is supplied by the aircraftmanufacturer.

Oil pump assembly

The pump assembly includes one pressure pump and twoscavenge pumps which ensure the oil circulation in thesystem.

The pumps are mechanically driven by the accessory drivetrain.

The pressure pump is provided with a pressure relief valve.

The pumps are installed on the gearbox casing front face.

Oil filter

The filter retains any particles which may be contained inthe oil. The filter includes a by-pass valve and a pre-blockage pressure switch.

It is located on the upper part of the gearbox casing.

Strainers

The strainers protect the scavenge pumps from debris inthe system.

Cooling unit

The unit cools the lubricating oil by air circulation throughan oil cooler. The oil cooler is provided with a by-passvalve.

It is installed in the aircraft and it is supplied by the aircraftmanufacturer.

Centrifugal breather

The centrifugal breather separates the oil from the air-oilmist and vents the system.

It is located in the accessory drive train, in the upper partof the gearbox casing.

Indicating devices

- Filter pre-blockage pressure switch

- Low oil pressure switch

- Oil pressure transmitter

- Electrical magnetic plugs

- Level indicator, temperature probe and magnetic plug(supplied by the aircraft manufacturer).

Note: The oil system also supplies the torque transmitter.Refer to the "MEASUREMENT AND INDICATINGSYSTEMS" chapter for more details.

4.5OIL SYSTEM

ARRIUS 1


Training Notes

OIL SYSTEM - DESCRIPTION

SCAVENGEPUMPS

AIRCRAFT SYSTEM ENGINE SYSTEM

OIL PRESSURE TRANSMITTER

LOW OILPRESSURE SWITCH

COOLING UNIT(cooler provided with

a by-pass valve)

PRESSURE PUMP(with pressure relief valve)

ELECTRICALMAGNETIC PLUGS

MAGNETICPLUG

STRAINER

CENTRIFUGALBREATHER

TORQUETRANSMITTER

TEMPERATUREPROBE

OILRESERVOIR

OILFILTER

STRAINER

4.6OIL SYSTEM


ARRIUS 1

Edition: May 2006

Training Notes

OIL SYSTEM - OPERATION

The main functions of the oil system are: supply, scavenge,breathing and indicating.

Supply

The supply system provides oil under pressure to thedifferent engine sections which require lubrication.

The pressure pump draws the oil from the reservoir anddelivers it under pressure to the system. A pressure reliefvalve limits maximum pressure by returning oil to thepump inlet.

The oil is then delivered, through the filter and a restrictor,to the engine sections which require lubrication:

- Gears and bearings of the accessory drive train andreduction gear train

- Gas generator front bearing

- Gas generator rear bearing

- Power turbine front bearing

- Torquemeter.

Scavenge

After lubrication, the oil falls by gravity to the bottom ofthe sumps. The oil is then immediately drawn away by thescavenge pumps and returned to the reservoir through thecooling unit (dry sump system).

Strainers protect the scavenge pumps against any particleswhich may be held in the lubrication oil.

Breathing

The reservoir oil mist and the oil mist which results fromlubrication are returned to the reduction gearbox where theoil is separated from the air by a centrifugal breather whichvents the oil system to the exhaust through an externalpipe.

Indication of the oil system operation

The indication is ensured by the following components:

- Low oil pressure switch

- Oil pressure transmitter

- Electrical magnetic plugs

- Oil filter pre-blockage pressure switch

- Aircraft components: level indicator, magnetic plug andtemperature probe.

4.7OIL SYSTEM

ARRIUS 1


Training Notes

OIL SYSTEM - OPERATION

SUPPLY

SCAVENGE

BREATHING

AIR VENT

OIL SYSTEM INDICATING

Level, pressure, temperature,magnetic particles, low pressure

and filter pre-blockage

4.8OIL SYSTEM


ARRIUS 1

Edition: May 2006

Training Notes

OIL RESERVOIR

Function

The reservoir contains the volume of oil required forengine lubrication.

Position

- It is installed in the aircraft.


- Aircraft manufacturer's supply

- Oil system capacity: 4.8 litres (1.25 US G

- Max. consumption: 0.3 l/h (0.08 US G/hr).

Main components

- Filler cap

- Oil level sight glass (x 2)

- Air vent union

- Oil return union

- Oil supply union

- Magnetic drain plug

- Temperature probe.

Note: Refer to manufacturer's documentation fordescription and operation information.

4.9OIL SYSTEM

ARRIUS 1


Training Notes

OIL RESERVOIR

BREATHING(to centrifugal

breather)

OILRETURN

OILSUPPLY

INTERFACESAircraft/Engine

MAGNETIC DRAINPLUG

Aircraft manufacturer's supply

Oil system capacity4,8 litres (1.25 US G)

Max. consumption0,3 l/h (0.08 US G/hr)

FILLERCAP

TEMPERATUREPROBE

OIL LEVELSIGHT GLASS

OILRESERVOIR

Note: Refer to manufacturer's documentation for description and operation information.

4.10OIL SYSTEM


ARRIUS 1

Edition: May 2006

Training Notes

OIL PUMPS - GENERAL - DESCRIPTION

Function

The pumps ensure oil circulation in the system.

Position

- In the system: the pressure pump is located downstreamof the oil reservoir and the scavenge pumps upstream ofthe cooling unit

- On the engine: the oil pump unit is installed on thegearbox front face.


- Type: spur gear type

- Pressure relief valve setting: 1500 kPa (217.5 PSI).

Description

They are driven at a speed proportional to N1.

The pump assembly includes:

- The pump drive shaft

- The driven shaft

- The spur gear type pumps:• Pressure pump• Front bearing scavenge pump• Rear bearing scavenge pump

- The pump bodies which comprise the oil inlet and outletunions

- The seal support plate

- The pressure relief valve.

O'ring seals ensure the sealing between the various pumpbodies.

Note: The accessory drive train is provided with acoupling sleeve which is engaged on the oil pumpassembly.

4.11OIL SYSTEM

ARRIUS 1


Training Notes

OIL PUMPS - GENERAL - DESCRIPTION

TypeSpur gear type

Pressure relief valve setting1500 kPa (217.5 PSI)

OIL PUMPS PRESSUREPUMP

SEAL SUPPORTPLATE

DRIVENSHAFT

REAR BEARINGSCAVENGE PUMP

FRONT BEARINGSCAVENGE PUMP

PUMP DRIVESHAFT

4.12OIL SYSTEM


ARRIUS 1

Edition: May 2006

Training Notes

OIL PUMPS - OPERATION

Principle of operation of a spur gear type pump

The pumps are spur gear type. One pump has two gears:one drive gear, and one driven gear. The oil flows betweenthe pump gears and the casing; the oil is then deliveredunder pressure to the system.

Pressure pump operation

The pressure pump draws the oil from the reservoir anddelivers it under pressure to the supply system.

The full pressure pump flow is used (full flow, oil pressureas a function of the rotation speed and the oil viscosity).

Operation of the pressure relief valve

The pressure relief valve limits the pressure at the pressurepump outlet.

The valve returns the excess oil to the pressure pump inletwhen the pressure is higher than the valve setting.

In normal operation, the pressure relief valve is closed.

Scavenge pump operation

Two scavenge pumps, one for the reduction gearbox andfront bearings, and one for the rear bearings, return the oilto the reservoir.

The scavenge pump flow is higher than the pressure pumpflow (dry sump system).

4.13OIL SYSTEM

ARRIUS 1


Training Notes

OIL PUMPS - OPERATION

OIL OUTLET(to filter)

OIL OUTLET(to cooling unit)

SCAVENGE(reduction gearboxand front bearings)

SCAVENGE(rear bearings)

OIL INLET(from reservoir)

Oil inlet Oil outlet

DRIVE GEAR

DRIVEN GEAR

OPERATION OF THEPRESSURE RELIEF VALVE

PRINCIPLE OF OPERATIONOF A SPUR GEAR TYPE PUMP

Normal operation(valve closed)

Overpressure(valve open)

4.14OIL SYSTEM


ARRIUS 1

Edition: May 2006

Training Notes

OIL FILTER - GENERAL

Function

The filter retains any particles that may be held in the oil.

Position

- In the system: downstream of the pressure pump

- On the engine: the oil filter is installed beside the fuelfilter inside the filter assembly which is mounted at theupper part of the gearbox casing.


- Type: metal cartridge (or fiberglass)

- Filtering ability: 20 microns

- Pre-blockage pressure switch setting: ∆P 120 kPa(18 PSID)

- By-pass valve setting: ∆P 220 kPa (32 PSID).

Main components

- Pre-blockage pressure switch

- By-pass valve

- Filtering element

- Filter bowl

- Filter casing.

4.15OIL SYSTEM

ARRIUS 1


Training Notes

OIL FILTER - GENERAL

PRE-BLOCKAGEPRESSURE SWITCH

BY-PASSVALVE

FILTERINGELEMENT

FILTERBOWL

FILTERCASING

TypeMetal cartridge (or fiberglass)

Filtering ability20 microns

Pre-blockage pressure switch∆P 120 kPa (18 PSID)

By-pass valve∆P 220 kPa (32 PSID)

4.16OIL SYSTEM


ARRIUS 1

Edition: May 2006

Training Notes

OIL FILTER - DESCRIPTION

The assembly comprises:

- The pre-blockage pressure switch

- The by-pass valve (valve, magnetic rod and spring)

- The filtering element

- The filter bowl

- The filter casing (base)

- The heat exchanger wall (oil cooling by fuel heating).Refer to the chapter "FUEL SYSTEM"

- The filter drain valve.

Note: During filter removal, the drain valve lifts from itssupport. The oil which remains in the filter thenflows to the gearbox sump through the drain orifice.

4.17OIL SYSTEM

ARRIUS 1


Training Notes

OIL FILTER - DESCRIPTION

FILTERINGELEMENT

Oil inlet

Oil outlet

DRAIN VALVE

FILTER DRAIN

To the reduction gearbox


BY-PASSVALVE

FILTERBOWL

HEAT EXCHANGERWALL

BASE

Fuel inlet

Fuel filter

4.18OIL SYSTEM


ARRIUS 1

Edition: May 2006

Training Notes

OIL FILTER - OPERATION

Normal operation

In normal operation, the oil delivered by the pressurepump enters the filtering unit through an orifice located inthe filter base.

The oil flows between the fuel filter wall and the heatexchanger wall (oil cooling by fuel heating).

The oil enters the oil filter through an orifice locatedbetween the two chambers and then flows through thefiltering element. The filtered oil then flows to the differentengine sections which require lubrication.

Pre-blockage

When the filtering element becomes dirty, the pressuredifference on the by-pass valve increases. For a pressuredifference higher than the pre-blockage switch setting, theby-pass valve moves slightly to release the switch whichprovides indication in the cockpit.

The pre-blockage switch is automatically rearmed as thepressure difference decreases (normally at engine shut-down).

Blockage (by-pass operation)

When the pressure difference on the by-pass valve ishigher than by-pass valve setting, the valve opens andallows the supply of unfiltered oil to the engine.

4.19OIL SYSTEM

ARRIUS 1


Training Notes

OIL FILTER - OPERATION

PRE-BLOCKAGE

NORMAL OPERATION

BLOCKAGE

SLIGHT BLOCKAGE OF THEFILTERING ELEMENT

BY-PASS VALVEOPENING

FILTERING ELEMENTOPERATION(filter clean)

BLOCKAGE OF THEFILTERING ELEMENT


INDICATION INDICATION


4.20OIL SYSTEM


ARRIUS 1

Edition: May 2006

Training Notes

PRE-BLOCKAGE PRESSURE SWITCH

Function

The pressure switch provides a cockpit indication of the oilfilter pre-blockage.

Position

- On the engine: located at the upper part of the oil filter.


- Type: with plunger

- Setting: ∆P 120 kPa (18 PSID)

- Cockpit indication.

Functional description

It has a valve fitted with a spring, and a magnetic rod. Themicroswitch plunger faces the magnetic rod.

This plunger is inoperative at lower oil temperature due tothe thermal lock.

The switch thermal lock is released for an increasingtemperature of + 50°C (122°F) and actuated for a decreasingtemperature of + 30°C (86°F).

When the filtering element becomes dirty, the valve doesn’topen but moves down slightly and reduces the magneticfield between the magnetic rod and the plunger. Then thereleased plunger closes the electrical circuit and theindication is given in the cockpit.

The indication is cancelled if the differential pressurebecomes lower than ∆P 100 kPa (14.5 PSID) (automaticreset).

4.21OIL SYSTEM

ARRIUS 1


Training Notes


TypeWith plunger

Setting∆P 120 kPa (18 PSID)

Cockpit indication


FILTERINGUNIT

Oil inlet

Oil outlet

MAGNETICROD

ELECTRICALCONNECTOR

MICROSWITCH PLUNGER

THERMAL LOCK( +50°C / 122°F)( +30°C / 86°F)

BY-PASSVALVE

SPRING

FILTERINGELEMENT

4.22OIL SYSTEM


ARRIUS 1

Edition: May 2006

Training Notes

COOLING UNIT

Function

The unit cools the oil which has lubricated the engine. Thecooling is ensured by air circulation through a cooler.

Position

- In the system: between the scavenge pumps and the oilreservoir

- The cooling unit is installed in the aircraft.



- Type: air-oil cooler

- By-pass and thermostatic valve:• Fully open: < 96°C (205°F)• Fully closed: > 106°C (223°F).

Description

The unit mainly comprises a cooler and a fan. The oil iscooled by circulation of air.

The unit is provided with a by-pass and thermostatic valve.

Note: Refer to aircraft manufacturer' s documentationfor further information.

4.23OIL SYSTEM

ARRIUS 1


Training Notes

COOLING UNIT

From scavengepumps

To reservoir

AIR

OILCOOLER


COOLINGUNIT Aircraft manufacturer's supply

TypeAir-oil cooler

By-pass andthermostatic valve

Fully open: < 96°C (205°F)Fully closed: > 106°C (223°F)

Cooling airoutlet

BY-PASS ANDTHERMOSTATIC VALVE

OIL COOLER COOLING FAN

Note: Refer to manufacturer's documentation for further information.

4.24OIL SYSTEM


ARRIUS 1

Edition: May 2006

Training Notes

CENTRIFUGAL BREATHER

General

Function

The centrifugal breather separates the oil from the air-oilmist resulting from lubrication and vents the oil system.

Position

- On the engine: formed by the starter-generator drivegear.


- Type: centrifugal

- Air vent: through the rear part of the hollow shaft,connected to the exhaust.

Description

The centrifugal breather is formed by the starter-generatordrive gear.

The gear is supported by two ball bearings. Graphite sealsensure the sealing of the ball bearings.

Operation

The centrifugal breather is driven by the intermediate gear.

When the engine is running, the air-oil mist resulting fromlubrication passes through the breather:

- Centrifugal force throws the oil droplets out into thereduction gearbox

- The de-oiled air is vented through an external pipe intothe exhaust pipe.

4.25OIL SYSTEM

ARRIUS 1


Training Notes

CENTRIFUGAL BREATHER

AIR VENT(to the exhaust pipe

through an external pipe)

AIR-OIL MIST(from reservoir)

BREATHER(starter-generator

drive gear)

GRAPHITESEAL

TypeCentrifugal

Air ventThrough the rear partof the hollow shaft,

connected to the exhaust

OILDROPLETS

REDUCTIONGEARBOX

CASING

INTERMEDIATE GEAR(accessory drive train)

DE-OILEDAIR

GRAPHITESEAL

4.26OIL SYSTEM


ARRIUS 1

Edition: May 2006

Training Notes

ELECTRICAL MAGNETIC PLUGS

Function

The magnetic plugs retain magnetic particles contained inthe oil and provide cockpit indication.

Position

- In the system: 2 electrical magnetic plugs upstream ofthe scavenge pumps

- On the engine:• 1 electrical magnetic plug at the front lower part of

the reduction gearbox• 1 electrical magnetic plug underneath the combustion

chamber casing.


- Type: magnetic probe

- Quantity: 2 in parallel


Main components

- Magnetic plug body

- Magnetic probe

- Electrical connector (connection with the cockpit)

- Locking slot

- Mounting pins.

Note: A magnetic plug is located at the reservoir outlet(supplied by the aircraft manufacturer).

Operation

The electrical magnetic plugs have magnetic probes whichattract magnetic particles in the scavenge return lines:

- Of the front part (reduction gearbox and gas generatorfront bearing)

- Of the rear part (gas generator rear bearing and powerturbine bearings).

When particles bridge the gap between the magnetic poles,it provides cockpit indication.

4.27OIL SYSTEM

ARRIUS 1


Training Notes

ELECTRICAL MAGNETIC PLUGS

OPERATION WITH PARTICLES

+ INDICATION

BRIDGE OFPARTICLES

INDICATION

LOCKING SLOT

MOUNTINGPIN

TypeMagnetic probe

Quantity2 in parallel

Cockpit indication

ELECTRICAL CONNECTOR(connection with the cockpit)

ELECTRICALMAGNETIC PLUG

STRAINER

MAGNETICPROBE

4.28OIL SYSTEM


ARRIUS 1

Edition: May 2006

Training Notes

STRAINERS

Function

The strainers protect the scavenge pumps against largeparticles which might be in the oil.

Position

- In the system: 1 strainer upstream of each scavengepump

- On the engine: 1 strainer at the front lower part of thereduction gearbox and 1 underneath the combustionchamber casing.


- Type: wide mesh filter and electrical magnetic plugreceptacle

- Quantity: 2


A strainer is a wide mesh filter which retains any largeparticles which may be held in the oil, in order to protectthe scavenge pumps.

The strainers are also provided with receptacles for theinstallation of the electrical magnetic plugs.

4.29OIL SYSTEM

ARRIUS 1


Training Notes

STRAINERS

TypeWide mesh filter and electrical

magnetic plug receptacle

Quantity2

WIDE MESHFILTER

STRAINERELECTRICAL MAGNETIC

PLUG RECEPTACLE

4.30OIL SYSTEM


ARRIUS 1

Edition: May 2006

Training Notes

LOW OIL PRESSURE SWITCH

Function

The pressure switch detects low pressure in the oil supplysystem and illuminates an indication in the cockpit.

Position

- In the system: downstream of the filter, in the oil supplysystem

- On the engine: on a mounting pad located on the gearboxcasing front face.


- Type: Diaphragm pressure switch

- Setting:• Decreasing pressure: 170 kPa (25 PSI)• Increasing pressure: 200 kPa (29 PSI)


Main components

- Pressure switch body

- Electrical connector (connection with the cockpit).

Operation

Normal operation

Increasing pressure: when the oil pressure is higher thanthe low oil pressure switch setting, the diaphragm lifts theplunger which acts on the microswitch and thus opens theelectrical circuit.

“Low pressure” operation

Decreasing pressure: when the oil pressure is lower thanthe setting, the diaphragm drops, and the plunger releasesthe microswitch and thus closes the electrical circuit andprovides the low oil pressure indication in the cockpit.

4.31OIL SYSTEM

ARRIUS 1


Training Notes

LOW OIL PRESSURE SWITCH

TypeDiaphragm pressure switch

SettingDecreasing pressure

170 kPa (25 PSI)Increasing pressure

200 kPa (29 PSI)

Cockpit indicationLOW OIL

PRESSURE SWITCH

ELECTRICALCONNECTOR

(to the cockpit)

4.32OIL SYSTEM


ARRIUS 1

Edition: May 2006

Training Notes


Function

This transmitter provides signals of oil pressure to thecockpit.

Position

- In the system: downstream of the filter, in the oil supplysystem

- On the engine: on a mounting pad located on the gearboxcasing front face.


- Type: resistive

- Output signals: electrical voltage proportional to the oilpressure


Main components

- Transmitter body

- Electrical connector (connection with the cockpit).

Operation

It has a resistor bridge printed on a flexible support.

This flexible support is subjected to the oil pressure and theresistor bridge is supplied electrically from the indicatingsystem. Changes in oil pressure cause movement of theflexible support which changes the resistance and thus theoutput voltage.

4.33OIL SYSTEM

ARRIUS 1


Training Notes


TypeResistive

Output signalElectrical voltage

proportional to the oil pressure

Cockpit indication

OIL PRESSURETRANSMITTER

OIL PRESSURETRANSMITTER

ELECTRICALCONNECTOR

(connection with the cockpit)

4.34OIL SYSTEM


ARRIUS 1

Edition: May 2006

Training Notes

OIL TEMPERATURE PROBE

General

Function

The oil temperature probe measures the oil temperature atthe oil reservoir outlet and provides indication to thecockpit.

Position

- In the oil system: the probe is located downstream of theoil reservoir.



- Type: nickel resistance

- Resistance value:• 100 Ω at 0°C (32°F)• 165 Ω at 100°C (212°F)

- Output signal: electrical voltage proportional to the oiltemperature



The oil temperature sensor is a nickel resistor housed in asteel probe; the resistance value varies according to thetemperature.

4.35OIL SYSTEM

ARRIUS 1


Training Notes

OIL TEMPERATURE PROBE


Aircraft manufacturer's supply

TypeNickel resistor

Resistance value100 Ω at 0°C (32°F)

165 Ω at 100°C (212°F)

Output signalElectrical voltage proportional

to the oil temperature

Cockpit indication

OIL TEMPERATUREPROBE

1

2

3CONSTANT I

(mA)

NICKELRESISTOR

VARIABLE OUTPUTVOLTAGE

CONTROL PANEL(to oil temperature

indicator)

4.36OIL SYSTEM


ARRIUS 1

Edition: May 2006

Training Notes

OIL PIPES

This part deals with the external pipes and internal ducts ofthe oil system.

External pipes

Supply

- From reservoir to pressure pump

- From air intake casing to rear bearings.

Scavenge

- From rear bearings to strainer support box

- From strainer support box to air intake casing

- From scavenge pumps to oil cooler

- From oil cooler to reservoir.

Breathing

- From reservoir to reduction gearbox

- From reduction gearbox to exhaust pipe.

Internal ducts

Supply

- From pressure pump to oil filter

- From oil filter:• To front bearings• To gears and bearings of the reduction gear train• To gears and bearings of the accessory drive train• To torquemeter• To air intake for the rear bearings.

Scavenge

- From reduction gearbox to scavenge pump.

4.37OIL SYSTEM

ARRIUS 1


Training Notes

OIL PIPES

AIR VENT(from reduction gearbox

to exhaust pipe)

SUPPORT BOX(strainer and electrical

magnetic plug)

SUPPLY(rear bearings)

OIL INLET UNION(from reservoir)

OIL OUTLET UNION(to oil cooler) TOP VIEW

LEFT SIDE VIEW AIR VENT(from reduction gearbox

to exhaust pipe)AIR VENT UNION(from reservoir)

SCAVENGE(rear bearings)

5.1AIR SYSTEM

ARRIUS 1


Training Notes

5 - AIR SYSTEM

- Air system (75-00-00) ............................................ 5.2

- Internal air system ................................................. 5.4

- Air tappings ............................................................ 5.6

- Air tapping unions (75-30-02) ............................... 5.8

- Air pressure sensor (77-30-03) .............................. 5.10

- Air temperature probe (77-30-04) ........................ 5.12 to 5.13


5.2AIR SYSTEM


ARRIUS 1

Edition: May 2006

Training Notes

AIR SYSTEM

Function

The engine air system includes:

- The internal air system which ensures:• The pressurisation of the labyrinth seals• The cooling of the engine internal parts• The balance of forces on the rotating assemblies

- Air tappings which ensure:• The start injector ventilation• The air pressure supply to the control system• The aircraft air system supply.

Note: Refer to the various systems for the position, maincharacteristics, description and operation.

5.3AIR SYSTEM

ARRIUS 1


Training Notes

AIR SYSTEM

INTERNAL AIR SYSTEM

- Pressurisation of labyrinth seals- Cooling of engine internal parts- Balance of forces on the rotating assemblies

AIR TAPPINGS

- Start injector ventilation- Air pressure supply to the control system- Aircraft air system supply

5.4AIR SYSTEM


ARRIUS 1

Edition: May 2006

Training Notes

INTERNAL AIR SYSTEM

Function

The internal air system pressurises the labyrinth seals,cools certain internal parts and provides a balancing offorces.


Pressurisation of labyrinth seals

- The air tapped from the compressor wheel passes throughthe internal ducts of the air intake casing, to pressurisethe gas generator front bearing housing

- The air tapped from the tip of the compressor wheel,flows behind the compressor through the curvic-coupling.It then passes between the gas generator turbine shaftand the turbine disc and goes out through holes in therear of the turbine disc to pressurise the rear bearinglabyrinths.

Cooling of internal parts

The air from the outlet of the compressor diffuser, coolsthe following components:

- The combustion chamber walls

- The turbine nozzle guide vanes

- The front face of the gas generator turbine disc

- The blade roots of the gas generator turbine.

The air tapped from the outlet of the compressor wheel,cools the following components:

- The rear face of the gas generator turbine disc

- The front face of the power turbine disc.

Balance of forces on rotating assemblies

Some of the diffuser outlet air applies a compensationpressure on the balance piston located at the front of the gasgenerator turbine through a labyrinth.

5.5AIR SYSTEM

ARRIUS 1


Training Notes

INTERNAL AIR SYSTEM

P2.5 - AIR TAPPED FROM THE MIDDLEOF THE COMPRESSOR WHEEL

AIR TAPPED FROM THE TIPOF THE COMPRESSOR WHEEL

P3 - AIR TAPPED FROM THE OUTLETOF THE COMPRESSOR DIFFUSER

LABYRINTH SEAL OF THEGAS GENERATOR FRONT BEARING

GAS GENERATOR REAR BEARINGLABYRINTH SEAL

POWER TURBINE BEARINGLABYRINTH SEAL

AIR TAPPED FROM THE TIPOF THE COMPRESSOR WHEEL

BALANCEPISTON

5.6AIR SYSTEM


ARRIUS 1

Edition: May 2006

Training Notes

AIR TAPPINGS

Function

The air tappings are used for:

- Start injector ventilation

- The control system (pressure signal)

- Aircraft services.

Start injector ventilation

An air bleed (located on the engine right side) bleedscompressor delivery pressure air. This air supplies, throughan external pipe, the start electro-valve for start injectorventilation.

Ventilation of the start injectors purges fuel from them atthe end of starting and prevents carbonisation.

Air pressure signal for the control system

The air tapped from the combustion chamber casing (P3),is also used as a pressure signal for the control system.

P3 air is tapped through a calibrated restrictor; and is takenby an external pipe to a pressure sensor, to provide a P3signal to the Digital Control Unit.

Note: The engine has also a temperature probe installedon the plenum lower part (refer to following pagesfor more details).

Aircraft services

The engine has an air bleed on each side of the combustionchamber casing. The air, tapped from the compressoroutlet, can be used by the aircraft systems for variouspurposes (refer to following pages for more details).

5.7AIR SYSTEM

ARRIUS 1


Training Notes

AIR TAPPINGS

DIGITAL CONTROLUNIT

STARTINJECTORS

P3 PRESSURESIGNAL TO THE

CONTROL SYSTEM

AIRCRAFTSERVICES

VENTILATIONOF START INJECTORS

STARTELECTRO-VALVE

AIR PRESSURESENSOR

P3 air

5.8AIR SYSTEM


ARRIUS 1

Edition: May 2006

Training Notes

AIR TAPPING UNIONS

Function

The air tapping unions allow air to be tapped from thecentrifugal compressor outlet.

Position

Aircraft air tappings

The aircraft air tappings are located on each side of thecombustion chamber casing.

Start injector ventilation tapping

The air tapping for the ventilation of the start injectors isinstalled on the right upper part of the combustion chambercasing.

Air pressure sensor tapping

The tapping for the pressure sensor is installed on the leftupper part of the combustion chamber casing.


- Quantity: 4

- Air pressure: 860 kPa (125 PSI)

- Air temperature: 320°C (608°F).


The air tappings have unions which are provided withrestrictors to limit flow in order to prevent loss of enginepower in the event of a broken pipe.

The air tapping not in use is provided with a blank.

Note: The air tapping use is limited since it affects theengine performance.

5.9AIR SYSTEM

ARRIUS 1


Training Notes

AIR TAPPING UNIONS

RESTRICTOR

UNION

START INJECTORVENTILATION TAPPING

PRESSURE SENSORTAPPING

Quantity4

Pressure860 kPa (125 PSI)

Temperature320°C (608°F)

AIRCRAFT AIRTAPPING UNION

5.10AIR SYSTEM


ARRIUS 1

Edition: May 2006

Training Notes

AIR PRESSURE SENSOR

Function

The sensor measures the air pressure at the centrifugalcompressor outlet and provides a pressure signal to theDigital Control Unit.

Position

- The sensor is secured on the upper part of the gearboxcasing. It is connected to an air tapping located on the leftside of the combustion chamber casing by means of anexternal pipe.


- Type: resistive

- Output signal: voltage proportional to the P3 air pressure.

Main components

- Air pressure sensor

- Pipe

- Air tapping.


The air pressure sensor is of resistive type. It has a resistorbridge printed on a flexible support subjected to P3 airpressure.

The support deformations, according to the air pressure,create an output voltage proportional to the pressure, fora constant input voltage.

The output voltage is used by the Digital Control Unit.

5.11AIR SYSTEM

ARRIUS 1


Training Notes

AIR PRESSURE SENSOR

Vs3

2

4

5

1-

-

+

+Ve

TypeResistive

Output signalVoltage proportional

to the P3 air pressure

AIR PRESSURESENSOR

PIPE AIRTAPPING

Ve: Constant input voltage (resistor bridge supply)Vs: Variable output voltage (measurement)

PRESSURESENSOR

TO DIGITALCONTROL UNIT

5.12AIR SYSTEM


ARRIUS 1

Edition: May 2006

Training Notes

AIR TEMPERATURE PROBE

Function

The probe measures the ambient air temperature at the airintake and provides the temperature indication to theDigital Control Unit (fuel control).

Position

- The probe is secured on the lower part of the air intakeplenum.


- Probe supplied by the engine manufacturer but installedon the air intake volute which is supplied by the aircraftmanufacturer

- Type: platinum resistor

- Resistor value: 100 Ω at 0°C (32°F)

- Output signal: voltage proportional to the ambient airtemperature.

Main components

- Electrical connector (connection with the DCU)

- Mounting flange

- Seal

- Probe.


The temperature probe has a platinum resistor whoseresistance varies according to the temperature.

The Digital Control Unit supplies the resistor with a directcurrent and measures the output voltage available at theresistor terminals.

5.13AIR SYSTEM

ARRIUS 1


Training Notes

AIR TEMPERATURE PROBE

TypePlatinum resistor

Resistor value100 Ω at 0°C (32°F)

Output signalVoltage proportional to

the ambient air temperature

ELECTRICALCONNECTOR

(to DCU)

MOUNTINGFLANGE

SEAL

PROBEVoltage

Constant I(mA)

Resistor

DIGITALCONTROL UNIT

6.1FUEL SYSTEM

ARRIUS 1


Training Notes

6 - FUEL SYSTEM- Fuel system (73-00-00) .......................................... 6.2- Fuel pressure transmitter (73-30-02) ................... 6.16- LP fuel pump - Alternator unit (73-10-01) ......... 6.18- Fuel filter (73-10-02) .............................................. 6.24- Pre-blockage pressure switch (73-30-01) ............. 6.30- HP fuel pump and metering unit (73-10-03)........ 6.32- Stop electro-valve (73-10-04) ................................ 6.38- Fuel valve assembly (73-10-05) ............................ 6.42- Start injectors (73-10-06) ..................................... 6.48- Main injectors (73-10-07) ...................................... 6.54- Combustion chamber drain valve (73-10-08) ........ 6.60- Fuel pipes (73-10-09)............................................. 6.62 to 6.63


6.2FUEL SYSTEM


ARRIUS 1

Edition: May 2006

Training Notes

Main components

- Low Pressure unit (pump and alternator)

- Fuel filter

- High Pressure unit (pump and metering unit)

- Valve assembly

- Injection system

- Sensors and input signals.

FUEL SYSTEM - GENERAL

Function

The fuel system ensures fuel supply, distribution, control,metering and injection.

Position

The fuel reservoir and the supply system are installed onthe aircraft. The other fuel system components are installedon the engine.

The Digital Control Unit is installed in the aircraft cargocompartment.


- Supply from the aircraft system and the engine pumps

- Main fuel injection (pre-vaporisation)

- Start injection by injectors

- Distribution by a valve assembly

- Fuel flow control by the DCU and the metering unit.

6.3FUEL SYSTEM

ARRIUS 1


Training Notes

FUEL SYSTEM - GENERAL

P3

EngineAircraft

LOW PRESSUREUNIT

(pump and alternator)

HIGH PRESSUREUNIT

(pump andmetering unit)

FUELFILTER

MANUALCONTROL

INJECTIONSYTEM

FUEL RESERVOIR

FUEL VALVEASSEMBLY

SENSORS ANDINPUT SIGNALS

DIGITALCONTROL UNIT

6.4FUEL SYSTEM


ARRIUS 1

Edition: May 2006

Training Notes

FUEL SYSTEM - DESCRIPTION

The fuel system includes the following components:

Booster pump (low pressure aircraft system).

Low pressure pump unit

This unit includes a centrifugal low pressure pump and analternator to electrically supply the Digital Control Unit.

Filtering unit

The filtering unit includes a filtering element, a pre-blockage pressure switch, a by-pass valve and a filterblockage indicator.

High pressure pump unit - Metering unit

This unit includes a gear type high pressure pump fittedwith a pressure relief valve.

It also has a metering unit which includes:

- A constant ∆P valve

- A manual metering valve

- A fuel metering valve (controlled by the DCU)

- A bi-stable stop electro-valve.

Valve assembly

The assembly includes:

- A 3 way start electro-valve

- A pressurising valve

- A flow divider

- A manual purge device.

Start injectors: 4 injectors fitted around thecombustion chamber casing.

Main injectors: 10 pre-vaporising injectors installed atthe rear of the combustion chamber.

Fuel pressure transmitter

The fuel pressure transmitter is of resistive type. It ismounted at the left upper part of the gearbox casing.

Fuel flow transmitter

This is optional on the 1A and 1E and is standard on the1M. It is fitted in the delivery line between the meteringunit and the valve assembly.

6.5FUEL SYSTEM

ARRIUS 1


Training Notes

FUEL SYSTEM - DESCRIPTION

Filteringelement

FILTERINGUNIT

High Pressurepump

Manualcontrol

Meteringvalve

Pressurisingvalve

Flowdivider

MAININJECTORS

Startelectro-valve

STARTINJECTORS

Stopelectro-valve

BOOSTER PUMP(aircraft system)

Constant ∆Pvalve

FUEL PRESSURETRANSMITTER

Alternator

Low pressurepump

LOW PRESSUREPUMP UNIT

HIGH PRESSURE PUMP AND METERING UNIT

Pressure reliefvalve

Manual purgedevice

Flowmeter(optional)

FUEL VALVEASSEMBLY

By-passvalve

Pre-blockagepressure switch

Blockageindicator

6.6FUEL SYSTEM


ARRIUS 1

Edition: May 2006

Training Notes

FUEL SYSTEM - OPERATION (1)

This part deals with the following operating phases: pre-start, starting, normal operation, manual control and shut-down.

Pre-start

- The LP and HP pumps are not operating and there is nopressure in the system

- The constant ∆P valve is closed

- The stop electro-valve is in the "stop" position

- The start electro-valve is in the ventilation position

- The pressurising valve is closed

- The flow divider is closed

- The manual control valve is in the "neutral" position

- The metering valve can be in any position.

During the electrical power up, the metering valve isinitialised (refer to "CONTROL SYSTEM" chapter) andthe "stop" coil of the stop electro-valve is electricallysupplied.

6.7FUEL SYSTEM

ARRIUS 1


Training Notes


PRE-START

HP PUMP(stopped)

METERINGVALVE

(any position)

PRESSURISINGVALVE(closed)

FLOW DIVIDER(closed)

STARTELECTRO-VALVE

(in ventilation position)

STOPELECTRO-VALVE

(stop position)

CONSTANT∆P VALVE

(closed)

LP PUMP(stopped)

MANUAL CONTROL(neutral position)

6.8FUEL SYSTEM


ARRIUS 1

Edition: May 2006

Training Notes


Starting

The engine start command causes the pump to rotate andthe fuel is first supplied to the start injectors and then to themain injectors.

The constant ∆P valve operates and the fuel flow ismetered by the metering unit controlled by the DigitalControl Unit according to given laws (refer to the“CONTROL SYSTEM” chapter).

At the end of starting, the start components are de-energisedand the start injectors are ventilated. The speed is stabilisedat a controlled value.

6.9FUEL SYSTEM

ARRIUS 1


Training Notes


STARTING

HP PUMP(driven)

METERINGVALVE

(in control)

PRESSURISINGVALVE(open)

FLOWDIVIDER

(open)

STARTELECTRO-VALVE

(open)

STOPELECTRO-VALVE(running position)

CONSTANT∆P VALVE(in control)

LP PUMP(driven)

BOSTER PUMP(in operation)

MAININJECTORS

(supplied)

LP PRESSURE

HP PRESSURE

METERED FUEL

STARTINJECTORS

(supplied)

6.10FUEL SYSTEM


ARRIUS 1

Edition: May 2006

Training Notes


Normal running

The required fuel flow is metered by the metering unit. Themetering unit position is determined by the Digital ControlUnit (refer to the “CONTROL SYSTEM” chapter).

The high pressure pump (HP) always supplies more fuelthan the engine requires. The excess fuel returns to the HPpump inlet through the constant ∆P valve.

The start injectors are continuously ventilated by airtapped from the combustion chamber casing.

6.11FUEL SYSTEM

ARRIUS 1


Training Notes


NORMAL RUNNING

HP PUMP(driven)

METERINGVALVE

(in control)

PRESSURISINGVALVE(open)

FLOWDIVIDER

(open)

STARTELECTRO-VALVE

(in ventilation)

P3 air

CONSTANT∆P VALVE(in control)

LP PUMP(driven)

MAININJECTORS

(supplied)

STARTINJECTORS(ventilated)

6.12FUEL SYSTEM


ARRIUS 1

Edition: May 2006

Training Notes


Manual control

In case of a fuel system failure, the fuel flow can bemanually controlled by actuating the manual meteringvalve in the "+" range (flow increase) or "-" range (flowdecrease).

In the "+" range, the fuel by-passes the main valve and isadded to the main valve flow. In the "-" range, the flow isdirectly limited by the manual metering valve.

6.13FUEL SYSTEM

ARRIUS 1


Training Notes


MANUAL CONTROL

Q ≠ 0Q

Q

MANUAL +

N

NORMAL (N)

Q = 0

Q

N

MANUAL -

Q = 0

N

6.14FUEL SYSTEM


ARRIUS 1

Edition: May 2006

Training Notes


Shut-down

The stop command opens the stop electro-valve whichreduces the fuel pressure downstream of the constant ∆Pvalve which opens fully.

The fuel then returns to the HP pump inlet; the flow to theinjectors is shut-off and the engine stops.

6.15FUEL SYSTEM

ARRIUS 1


Training Notes


SHUT-DOWN

CONSTANT∆P VALVE

(open)

STOPELECTRO-VALVE

(stop position)

6.16FUEL SYSTEM


ARRIUS 1

Edition: May 2006

Training Notes

FUEL PRESSURE TRANSMITTER

Function

The fuel pressure transmitter measures the fuel pressure atthe LP pump inlet.

Position

- In the system: upstream of the LP pump

- On the engine: secured by a clamp on a support locatedon the upper left side of the gearbox.


- Type: resistive

- Output signals: electrical voltage proportional to thefuel pressure


Main components

- Fuel pressure transmitter

- Support

- Fuel pipe

- Electrical harness.

Note: A optional fuel flow transmitter can be supplied asoptional equipment.


The fuel pressure transmitter is of resistive type. It has aresistor bridge printed on a flexible support.

This flexible support is subjected to the fuel pressure andthe resistor bridge is supplied electrically from the indicatingsystem. Changes in fuel pressure cause movement of theflexible support which changes the resistance and thus theoutput voltage.

The transmitter is subjected to the fuel pressure deliveredthrough a flexible pipe which is connected to the LP pump/alternator union.

6.17FUEL SYSTEM

ARRIUS 1


Training Notes

FUEL PRESSURE TRANSMITTER

Vs3

2

4

5

1-

-

+

+Ve

FUEL PIPE


SUPPORT

ELECTRICALHARNESS

FUEL FLOW TRANSMITTER(optional)

TypeResistive

Output signalElectrical voltage

proportional to the fuel pressure

Cockpit indication

Ve: Constant input voltage (resistor bridge supply)Vs: Variable output voltage (measurement)

PRESSURETRANSMITTER

ELECTRICALCONNECTOR

CONTROLPANEL

6.18FUEL SYSTEM


ARRIUS 1

Edition: May 2006

Training Notes

LP FUEL PUMP - ALTERNATOR UNIT -GENERAL

Function

The LP fuel pump - alternator unit supplies fuel underpressure and electrically supplies the Digital Control Unit.

Position

- On the front of the gearbox casing.


LP pump

- Type: centrifugal with ejector

- Rotation speed: 24052 RPM (100% N1).

Alternator

- Nominal power: 100 V.A.

- Operation: continuous

- Output voltage: 28 to 63 Volts.

Main components

- LP pump

- Alternator.

The following components can also be mentioned:

- Fuel inlet union (from aircraft system)

- Union and pipe of the pressure transmitter

- Drain union

- Alternator electrical connector.

6.19FUEL SYSTEM

ARRIUS 1


Training Notes

LP FUEL PUMP - ALTERNATOR UNIT - GENERAL

PRESSURETRANSMITTER

PIPE

FUEL INLETUNION

(from aircraftlow pressure system)

LP PUMP DRAINUNION

ALTERNATORCONNECTOR

(to Digital Control Unit)

ALTERNATOR

Return fromstop electro-valve

LP PUMPType

Centrifugal with ejector

Rotation speed24052 RPM (100% N1)

ALTERNATORNominal power

100 V.A.

OperationContinuous

Output voltage28 to 63 Volts

6.20FUEL SYSTEM


ARRIUS 1

Edition: May 2006

Training Notes

LP FUEL PUMP - ALTERNATOR UNIT -DESCRIPTION

LP pump unit

The LP pump includes the following components :

- The fuel inlet union and the return from the stop electro-valve

- The ejector jet which improves the LP pump fuel flow byventuri effect

- The LP pump rotor

- The pump and alternator drive shaft. The shaft issupported by two ball bearings

- The fuel return from the constant ∆P valve

- The fuel outlet to the filter through an internal duct

- Two seals on the drive shaft ensure that no fuel passesinto the gearbox. A drain between the seals drains anyleaks overboard.

Note: The accessory drive train is provided with a driveshaft which is engaged on the LP fuel pump -alternator.

Alternator

The alternator includes:

- A rotor mounted on the drive shaft of the LP fuel pump

- A stator housed in the alternator body and supported bytwo ball bearings (lubricated by oil mist). Two deliveryand return orifices are located on the support

- The sealing between the different elements is ensured byO’ring seals.

6.21FUEL SYSTEM

ARRIUS 1


Training Notes

LP FUEL PUMP - ALTERNATOR UNIT - DECRIPTION

DRAIN

BALLBEARING

ALTERNATOR(rotor and stator)

BALLBEARING

Fuel outlet(to filter)

Fuel return(from constant ∆P valve)

LP PUMPDRIVE SHAFT

EJECTORJET

Fuel inlet union(and return from

stop electro-valve)

SEALINGRINGS

LP PUMPROTOR

6.22FUEL SYSTEM


ARRIUS 1

Edition: May 2006

Training Notes

LP FUEL PUMP - ALTERNATOR UNIT -OPERATION

LP pump unit

The fuel supplied by the aircraft system enters the helicalinducer which draws the fuel into the impeller. The impellerpumps the fuel to the outlet.

A given quantity of fuel is returned to the ejector toincrease the inlet pressure of the LP pump.

An internal duct takes the fuel from the constant ∆P valveto the fuel outlet.

On engine shut-down, the fuel from the stop electro-valvereturns to the LP pump inlet.

6.23FUEL SYSTEM

ARRIUS 1


Training Notes

LP FUEL PUMP - ALTERNATOR UNIT - OPERATION

LP PUMP

From stopelectro-valve

BOOSTERPUMP

ALTERNATOR


To filter

Aircraft

6.24FUEL SYSTEM


ARRIUS 1

Edition: May 2006

Training Notes

FUEL FILTER - GENERAL

Function

The filter retains any particles that may be in the fuel inorder to protect the metering unit components.

Position

- In the system: at the LP pump outlet

- On the engine: it is installed beside the oil filter insidethe filter assembly located at the upper part of thegearbox casing.


- Type: metal cartridge (or fiberglass)

- Filtering ability: 20 microns

- Pre-blockage pressure switch: ∆P 120 kPa (17.4 PSID)

- By-pass valve: ∆P 220 kPa (32 PSID).

Main components

- Filtering element

- Pre-blockage pressure switch

- Blockage indicator (red visual indicator and transparentcover)

- By-pass valve

- Drain valve and drain union

- Filter bowl

- Filter casing.

6.25FUEL SYSTEM

ARRIUS 1


Training Notes

FUEL FILTER - GENERAL

TypeMetal cartridge (or fiberglass)

Filtering ability20 microns

Pre-blockage pressure switch∆P 120 kPa (17.4 PSID)

By-pass valve∆P 220 kPa (32 PSID)

BLOCKAGEINDICATOR

BY-PASSVALVE

FILTERBOWL

FILTERCASING

FILTERINGELEMENT

DRAIN UNION(fitted with a blank)

MOUNTING OF THEPRE-BLOCKAGE SWITCH

6.26FUEL SYSTEM


ARRIUS 1

Edition: May 2006

Training Notes

FUEL FILTER - DESCRIPTION

The main components of the fuel filter are:

- A heat exchanger wall (oil cooling by fuel heating).

- A filtering element (20 microns filtering ability)

- An electrical pre-blockage pressure switch

- A blockage indicator (red visual indicator and transparentcover)

- A by-pass valve

- A filter bowl

- A filter casing

- A drain valve and a drain union.

Note: During filter removal, the drain valve lifts from itssupport.

The fuel which remains in the filter then flowsthrough the drain orifice.

6.27FUEL SYSTEM

ARRIUS 1


Training Notes

FUEL FILTER - DESCRIPTION

Fuel inletFuel outlet

DRAINVALVE

FILTER DRAIN

To drain system

BLOCKAGEINDICATOR

BY-PASSVALVE

FILTERINGELEMENT

FILTERBOWL

FILTERCASING

HEAT EXCHANGERWALL

Oil inlet

Oil filter

6.28FUEL SYSTEM


ARRIUS 1

Edition: May 2006

Training Notes

FUEL FILTER - OPERATION

The operation is considered in normal operation, pre-blockage and blockage.

Normal operation

In normal operation, the fuel delivered by the LP pumpenters the filtering unit through an orifice located in thefilter base.

The fuel flows inside the heat exchanger (oil cooling andfuel heating).

The fuel enters the fuel filter and flows through thefiltering element. The filtering element retains particleslarger than 20 microns. The fuel then flows to the HPpump.

Pre-blockage

When the filter becomes dirty, the pressure differenceacross the filtering element increases. If the pressuredifference becomes higher than the pre-blockage pressureswitch setting, the electrical contact of the pressure switchcloses and gives a cockpit indication.

Blockage

When the pressure difference on the by-pass valve exceedsthe setting, the spring loaded mechanical indicator popsout.

The fuel then by-passes the filtering element and flows tothe HP pump.

6.29FUEL SYSTEM

ARRIUS 1


Training Notes

FUEL FILTER - OPERATION

NORMAL OPERATION

PRE-BLOCKAGE

BLOCKAGE

COCKPITINDICATOR

CLOGGEDFILTER

OPERATION OF THEBLOCKAGE INDICATOR


OPERATION

OPENING OFBY-PASS VALVE

ONSET OF FILTERBLOCKAGE

FILTERING ELEMENTOPERATION(20 microns)

6.30FUEL SYSTEM


ARRIUS 1

Edition: May 2006

Training Notes


General

Function

The pressure switch provides a cockpit indication of fuelfilter pre-blockage.

Position

- On the engine: on the base of the filtering unit.


- Type: with microswitch

- Pre-adjusted setting: ∆P 120 kPa (17.4 PSID)


Functional descripion

Normal operation

The filtering element is clean. The pressure difference oneach side of the filter is lower than the pre-blockagepressure switch setting: the electrical contact is open andthere is no indication in the cockpit.

Filter pre-blockage

When the filtering element becomes dirty, the pressuredifference on each side of the filter increases.

When the pressure difference exceeds the pressure switchsetting, the electrical switch closes and illuminates in thecockpit.

The indication stops as soon as the differential pressurebecomes lower than ∆P 60 kPa (8.7 PSID) (automaticreset of the pre-blockage switch).

6.31FUEL SYSTEM

ARRIUS 1


Training Notes


TypeWith microswitch

Pre-adjusted setting∆P 120 kPa (17.4 PSID)

Cockpit indication


ELECTRICALCONNECTOR

FILTERINGUNIT

Microswitchclosed

COCKPIT(indicator)

FILTER PRE-BLOCKAGE

6.32FUEL SYSTEM


ARRIUS 1

Edition: May 2006

Training Notes

HP FUEL PUMP AND METERING UNIT -GENERAL

Function

The HP fuel pump and metering unit supplies fuel underpressure to the fuel system and meters the fuel flowaccording to the power required. A pressure relief valverelieves the excess fuel pressure to the pump inlet.

Position

- In the system: downstream of the filtering unit.

- On the engine: the HP fuel pump and metering unit isinstalled on the gearbox front face.


HP fuel pump unit

- Type: gear type

- Pressure relief valve setting: 6000 kPa (870 PSI).

Metering unit

- Type: actuated by a stepper motor which is controlled bythe Digital Control Unit

- Position transmitter: resolver type.

Main components

The HP fuel pump and metering unit includes:

- An HP fuel pump unit and a pressure relief valve

- A metering unit (main metering valve, constant ∆Pvalve, manual metering lever).

6.33FUEL SYSTEM

ARRIUS 1


Training Notes

HP FUEL PUMP AND METERING UNIT - GENERAL

MANUALMETERING

LEVER

CONSTANT∆P VALVE

FUEL METERINGUNIT

HP PUMP

HP FUEL PUMP UNITType

Gear type

Pressure relief valve setting6000 kPa (870 PSI)

METERING UNITType

Actuated by a stepper motor whichis controlled by the Digital Control Unit

Position transmitter Resolver type

6.34FUEL SYSTEM


ARRIUS 1

Edition: May 2006

Training Notes

Metering unit

Manual metering valve

The manual metering valve includes:

- A rotary plate valve actuated by a control lever. Therotary plate valve has a fuel outlet orifice and a neutralnotch

- A fixed plate, with a fuel inlet orifice, a fuel outlet mainorifice, and a by-pass outlet orifice.

Main metering valve

Electrically, the unit includes a stepper motor (electricalrotary actuator) to drive the metering unit and a resolver totransmit the metering unit position to the Digital ControlUnit.

HP FUEL PUMP AND METERING UNIT -DESCRIPTION

HP fuel pump unit

The HP fuel pump unit includes:

- A shaft which drives the drive gear

- A driven gear

- A pressure relief valve

- Two lip seals which ensure the drive shaft sealing

- A drain which evacuates any leaks overboard

- Two journal bearings which support the pump gears

- A drive sleeve.

6.35FUEL SYSTEM

ARRIUS 1


Training Notes

HP FUEL PUMP AND METERING UNIT - DESCRIPTION

F0

HP PUMPUNIT

STOPELECTRO-VALVE

ELECTRICALCONNECTOR

DRIVENGEAR

DRIVEGEAR

DRAIN

DRIVESHAFT

LIPSEALS

JOURNALBEARINGS

PRESSURERELIEF VALVE

HP FUEL PUMP UNIT

STEPPERMOTOR

RESOLVER

REDUCTIONGEAR

DRIVESHAFT

HIGH PRESSUREPUMP

MANUALMETERING VALVE

METERINGVALVE

To pressurisingvalve

FromLP pump

PRESSURE RELIEFVALVE

6.36FUEL SYSTEM


ARRIUS 1

Edition: May 2006

Training Notes

The manual metering valve increases or reduces the fuelflow:

- To increase the power (above 0° position), the rotaryplate valve opens slightly the by-pass orifice and causesthe fuel to by-pass to the injectors

- To reduce the power (below 0° position), the rotary platevalve closes slightly the main orifice of the fixed plate.

At the manual metering valve outlet, the fuel flows to themetering unit. The flow depends on the cam positioncontrolled by the rotary actuator.

The fuel then flows through internal ducts and externalpipes to the start electro-valve, to the pressurising valveand to the LP pump through the stop electro-valve.

Engine shut-down

- In normal operation or in case of power turbineoverspeed, the engine shut-down is caused by the openingof the stop electro-valve which returns the fuel to the LPpump inlet

- In manual operation, the engine shut-down is effectedby closing the main and by-pass orifices of the fixedplate.

HP FUEL PUMP AND METERING UNIT -OPERATION

Engine normal operation

The fuel delivered by the LP pump enters the HP pumpafter filtering. The fuel is then delivered by the HP pumpthrough the internal ducts. A pressure relief valve returnsthe excess pressure to the HP pump inlet.

The fuel then enters the metering unit and flows to:

- The constant ∆P valve which maintains a constantdifference of pressure on both sides of the metering unitby returning the excess fuel to the LP pump outletthrough the ∆P return duct

- The manual metering valve which operates as follows:• In normal operation, the manual metering valve is in

the neutral position (0° on the graduated scale): themain orifice of the fixed plate faces the orifice of theplate valve and allows fuel flow to the metering unit

• In manual operation, the metering unit is "frozen" inthe position at the time of failure or of manualselection.

6.37FUEL SYSTEM

ARRIUS 1


Training Notes

HP FUEL PUMP AND METERING UNIT - OPERATION

HIGH PRESSUREPUMP

MANUALMETERING VALVE

METERINGVALVE

STOPELECTRO-VALVE

To startelectro-valve

To pressurisingvalve

To LP pumpinlet

To HP pumpinlet

From LP pump

CONSTANT∆P VALVE

PRESSURE RELIEFVALVE

ROTARY PLATEVALVE

MANUAL METERING VALVE(neutral position)

FIXEDPLATE

Mainorifice

By-passorifice

+-

6.38FUEL SYSTEM


ARRIUS 1

Edition: May 2006

Training Notes

STOP ELECTRO-VALVE - GENERAL -DESCRIPTION

Function

The stop electro-valve is used to shut-down the engine innormal operation or in case of power turbine overspeed.

Position

- In the system: between the fuel metering valve outletand the LP pump

- On the engine: at the lower part of the HP pump unit.


- Type: bistable, ball type.

Description

The stop electro-valve includes:

- An electrical connector

- An opening control coil A

- A closing control coil B

- A ball valve installed on a bistable reversible springplate

- A fuel outlet orifice (to LP pump inlet)

- A fuel inlet orifice (from the metering unit and constant∆P valve spring chamber)

- A mounting flange.

6.39FUEL SYSTEM

ARRIUS 1


Training Notes

STOP ELECTRO-VALVE - GENERAL - DESCRIPTION

F0

HP PUMPUNIT

STOPELECTRO-VALVE

ELECTRICALCONNECTOR

Fuel inlet(from fuel metering unitand constant ∆P valve)

Fuel outlet(to LP pump)

BALLVALVE

MOUNTINGFLANGE

ELECTRICALCONNECTOR

OPENINGCOIL A

CLOSINGCOIL B

SPRINGPLATE

TypeBistable, ball type

6.40FUEL SYSTEM


ARRIUS 1

Edition: May 2006

Training Notes

STOP ELECTRO-VALVE - OPERATION

Engine operation

The stop electro-valve is selected closed when start isinitiated, and when the starter - generator and the startingsystem are electrically supplied.

The supply of the B coil displaces the core to thecorresponding seat. The ball valve is in contact on its seatand closes the fuel return to pump inlet.

Note: The closing of the valve permits the fuel to flow tothe injectors.

Engine shut-down

The electrical supply of the A coil by the Digital ControlUnit displaces the core in oposite direction. The ball valvelifts from its seat and allows the fuel to return to the pumpinlet.

The stop electro-valve opening causes the fuel injectionpressure to drop, which closes the pressurising valve andcuts the injection manifold supply.

6.41FUEL SYSTEM

ARRIUS 1


Training Notes

STOP ELECTRO-VALVE - OPERATION

VALVE CLOSEDENGINE OPERATION

VALVE OPENENGINE SHUT-DOWN

Fuel inlet(from constant

∆P valve)

Fuel outlet(to LP pump)

CORE

OPENINGCOIL A

CLOSINGCOIL B

CORE

6.42FUEL SYSTEM


ARRIUS 1

Edition: May 2006

Training Notes

FUEL VALVE ASSEMBLY - GENERAL

Function

The valve assembly ensures fuel distribution under certainconditions:

- To supply in priority the start injectors

- To protect the start injectors from the risk of blockagedue to carbonisation

- To give supply preference to one main injector at lowfuel flow

- To allow the manual purge of the system.

Position

- In the system: between the metering unit and the injectionsystem

- On the engine: on a support secured at the upper part of

the combustion chamber casing.


- Type: 1 electro-valve and 2 spring-loaded valves

- Pressurising valve setting: 500 kPa (72.5 PSI)

- Flow divider setting: 150 kPa (22 PSI).

Main components

- Start electro-valve (3 way)

- Pressurising valve

- Flow divider

- Purge screw.

6.43FUEL SYSTEM

ARRIUS 1


Training Notes

FUEL VALVE ASSEMBLY - GENERAL

Type1 electro-valve

2 spring loaded valves

Pressurising valve setting500 kPa (72.5 PSI)

Flow divider setting150 kPa (22 PSI)

PURGESCREW

Maininjector supply

P3 air

Fuel inlet(from metering unit)

PRESSURISINGVALVE

STARTELECTRO-VALVE

FLOWDIVIDER

Preferenceinjector supply

Start injectorsupply

6.44FUEL SYSTEM


ARRIUS 1

Edition: May 2006

Training Notes

FUEL VALVE ASSEMBLY - DESCRIPTION

The valve assembly includes the start electro-valve, thepressurising valve, the flow divider and the purge screw.

Start electro-valve

The start electro-valve distributes fuel to the start injectors.

It is a 3-way, mono-stable valve. The 3 ways are: the fuelinlet, the fuel outlet to the start injectors and the P3 air inletfor the start injector ventilation.

The start electro-valve mainly includes:

- Two opposed ball valves integral with a shaft andsubjected to spring action in one direction and to theelectro-valve winding in the other direction

- Two filters

- An electrical connector.

Pressurising valve

The pressurising valve ensures fuel supply priority to thestart injectors during starting.

The pressurising valve includes a valve which is springloaded closed.

Flow divider

In case of low fuel flow, the flow divider closes and the fuelflows only to the preference injector. This is done in orderto preserve at least one injection point in the combustionchamber with an acceptable spraying quality-flow .

The flow divider includes:

- One valve, with leak rate, spring loaded closed (supplyof 9 of the main injectors)

- One restrictor, screwed into the flow divider body (supplyof the preference injector).

Purge screw

The valve assembly includes a purge screw which allowsthe manual purge of the fuel system (refer to"MAINTENANCE PROCEDURES" chapter).

6.45FUEL SYSTEM

ARRIUS 1


Training Notes

FUEL VALVE ASSEMBLY - DESCRIPTION

PRESSURISINGVALVE

FLOWDIVIDER

STARTELECTRO-VALVE

P3 air

Fuel outlet(to start injectors)

Fuel outlet(to preference injector)

Fuel outlet(to main injectors)

Fuel inlet(from

metering unit)

PURGESCREW

VALVEASSEMBLY

6.46FUEL SYSTEM


ARRIUS 1

Edition: May 2006

Training Notes

FUEL VALVE ASSEMBLY - OPERATION

Six operating phases are considered: engine stopped,initial phase of starting, starting, normal running, rapidfuel flow decrease and engine shut-down.

Engine stopped

There is no pressure in the system and no electrical supplyto the accessories. The pressurising valve and the flowdivider are closed, the start electro-valve is in the ventilationposition.

Initial phase of starting (N1 < 10%)

When start is selected, the start electro-valve coil iselectrically supplied. The start electro-valve opens andallows the fuel supply to the start injectors.

Starting (N1 > 10%)

It opens as soon as the fuel pressure is sufficient (about500 kPa / 72.5 PSI which is obtained for an N1 speed ofabout 10%).

When the fuel pressure is sufficient, the pressurising valveopens and supplies the main injection with fuel.

The fuel first flows to the preference injector.

The flow divider includes an internal jet (leak rate) whichsupplies the main injector manifold before the effectiveopening of the valve.

When the flow is sufficient, the flow divider opens andsupplies the main injectors with fuel.

Normal running (N1 > self-sustaining speed)

When the engine reaches self-sustaining speed(approx. 50 % of N1), the electrical supply to the startelectro-valve is cut. The start electro-valve closes the fuelsupply to the start injectors and allows their ventilation byP3 air in order to prevent carbonisation.

Rapid fuel flow decrease

When the fuel flow decreases rapidly, the flow dividercloses and reduces the fuel supply to the main injectors.

However, the flow is maintained to the preference injectorto avoid engine flame-out.

Shut-down

When shut-down is selected, the closing coil of the stopelectro-valve is electrically supplied and opens the thevalve. The pressurising valve closes and the fuel supply tothe injection system stops. The engine shuts-down.

6.47FUEL SYSTEM

ARRIUS 1


Training Notes

FUEL VALVE ASSEMBLY - OPERATION

P3P3

ENGINE STOPPED

SHUT-DOWN

INITIAL PHASE OF STARTING (N1 < 10%)

RAPID FUEL FLOW DECREASE

STARTING (N1 > 10%)

NORMAL RUNNING(N1 > self-sustaining speed)

6.48FUEL SYSTEM


ARRIUS 1

Edition: May 2006

Training Notes

START INJECTORS - GENERAL

Function

The start injectors spray fuel into the flame tube duringengine starting.

Position

- On the engine: around the combustion chamber casing.


- Quantity: 4

- Ventilation: by P3 air flow.

Main components

There are four start injectors. Two of them are installedbeside the igniter plugs.

The injectors are connected two by two to the half manifolds.

6.49FUEL SYSTEM

ARRIUS 1


Training Notes

START INJECTORS - GENERAL

Quantity4

VentilationBy P3 air flow

STARTINJECTOR

(with igniter plug)

STARTINJECTOR

FUEL SUPPLYHALF MANIFOLD

STARTELECTRO-VALVE

INJECTOR INJECTOR ANDIGNITER PLUG

INJECTOR ANDIGNITER PLUG

INJECTOR

6.50FUEL SYSTEM


ARRIUS 1

Edition: May 2006

Training Notes

START INJECTORS - DESCRIPTION

A start injector comprises:

- A mounting flange (secured by 2 screws)

- A circlip

- A filter

- A spring with a thrust washer

- A jet holder which swirls the fuel to the orifice plate bymeans of inclined and displaced planes

- An orifice plate provided in its centre with an orifice.

The two injectors located close to the igniter plugs aremounted on inclined bosses with a sleeve to secure thecombustion chamber. The two other injectors are mountedon flat bosses.

6.51FUEL SYSTEM

ARRIUS 1


Training Notes

START INJECTORS - DESCRIPTION

INJECTOR INJECTOR ANDIGNITER PLUG

INJECTOR ANDIGNITER PLUG

INJECTOR

IGNITERPLUG

INJECTOR(on inclined boss)

CIRCLIP

ORIFICEPLATE

JETHOLDER

SPRING

FILTER

MOUNTINGFLANGE

SLEEVE INJECTOR(on flat boss)

6.52FUEL SYSTEM


ARRIUS 1

Edition: May 2006

Training Notes

START INJECTORS - OPERATION

Starting

During starting, the start electro-valve permits the supplyof fuel to the start injectors.

The igniter plugs ignite the fuel sprayed by the injectorsinto the combustion chamber.

As soon as the pressurising valve opens the fuel flows tothe main injectors. The fuel sprayed by the injectors isignited and the combustion goes on.

Normal running

At the end of starting, the start electro-valve cuts off thestart injector fuel supply and allows their ventilation withP3 air in order to prevent their carbonisation.

The start injectors are continuously ventilated during theengine operation.

6.53FUEL SYSTEM

ARRIUS 1


Training Notes

START INJECTORS - OPERATION

NORMAL RUNNINGSTARTING

STARTELECTRO-VALVE

(open)

MAIN INJECTORSUPPLY

START INJECTORSUPPLY

STARTELECTRO-VALVE

(in ventilation position)

P3 air

IGNITERPLUG

START INJECTORVENTILATION

6.54FUEL SYSTEM


ARRIUS 1

Edition: May 2006

Training Notes

MAIN INJECTORS - GENERAL

Function

The main injection system sprays fuel into the combustionchamber in order to give stable and efficient combustion.

Position

- On the engine: around the rear part of the combustionchamber casing.


- Type: pre-vaporising injector

- Quantity: 10 injectors with 1 "preference" injector

- Fuel supply: through two half-manifolds and a pipe forthe "preference" injector.

Main components

There are ten main injectors. They are arranged as follows:

- 5 injectors connected by a half-manifold, on the left side

- 4 injectors connected by a half-manifold, on the rightside

- 1 injector connected by a pipe to the valve assembly.This is the "preference injector".

6.55FUEL SYSTEM

ARRIUS 1


Training Notes

MAIN INJECTORS - GENERAL

TypePre-vaporising injector

Quantity10 injectors

with 1 "preference" injector

SupplyThrough 2 half-manifolds and

a pipe for the "preference" injector

MAIN INJECTORS

HALF-MANIFOLDSUPPLY

(from valve assembly)

"PREFERENCE"INJECTOR

FUEL SUPPLY

RIGHTHALF-MANIFOLD

LEFTHALF-MANIFOLD

6.56FUEL SYSTEM


ARRIUS 1

Edition: May 2006

Training Notes

MAIN INJECTORS - DESCRIPTION

A main injector comprises:

- A mounting flange

- A circlip

- A filter

- A brazed jet

- The injector end is drilled with two calibrated holes,diametrically opposed. The two holes form the sprayingjet.

The injectors penetrate into the pre-vaporising tubes whichare welded on the flame tube.

6.57FUEL SYSTEM

ARRIUS 1


Training Notes

MAIN INJECTORS - DESCRIPTION

EXTERNALCASING FLANGEAIR

PRE-VAPORISINGTUBE

VAPORISEDFUEL

INJECTORMOUNTING FLANGE

FUEL

PRE-VAPORISING SYSTEMMOUNTING FLANGE

(welded on the flame tube)

MOUNTINGFLANGE

FILTER

JET

SPRAYINGJET

BODYENDARM

CIRCLIPFuelinlet

6.58FUEL SYSTEM


ARRIUS 1

Edition: May 2006

Training Notes

MAIN INJECTORS - OPERATION

Normal operation

When the fuel pressure exceeds a given value, thepressurising valve and the flow divider open and supplyfuel to the 10 main injectors through 2 half-manifolds andan external pipe (preference injector).

The fuel supplied by the main injectors is vaporised due tothe temperature and the mixture with combustion air.

The air-fuel mixture is sprayed into the flame-tube throughthe pre-vaporising tubes located in front of each maininjector and is continuously burnt.

Rapid fuel flow decrease

During rapid fuel flow decrease (rapid load decreasetransient phase), the pressure drop causes the flow dividerto close. The fuel supply to the main injectors is then cut.

However, the fuel flow to the "preference" injector ismaintained to avoid engine flame-out.

6.59FUEL SYSTEM

ARRIUS 1


Training Notes

MAIN INJECTORS - OPERATION

NORMAL OPERATION RAPID FUEL FLOW DECREASE(transient phase of rapid load decrease)

MAIN INJECTORFUEL SUPPLY

FLOW DIVIDER OPEN

PREFERENCE INJECTORFUEL SUPPLY

FLOW DIVIDER CLOSED(pressure drop at the metering valve outlet)

PREFERENCE INJECTORFUEL SUPPLY

6.60FUEL SYSTEM


ARRIUS 1

Edition: May 2006

Training Notes

COMBUSTION CHAMBER DRAIN VALVE

Function

This valve drains overboard any unburnt fuel remaining inthe combustion chamber.

Position

- On the engine: at the bottom of the combustion chambercasing lower part.


- Type: diaphragm

- Closing pressure: between 35 kPa (5 PSI) and 40 kPa(5.8 PSI) for a N1 speed of approx. 50%.


The drain valve includes:

- A union (screwed into the lower part of the combustionchamber casing)

- A valve actuated by the pressure in the combustionchamber. It opens at engine shut-down to drain fuel. Itcloses during starting when the air pressure becomeshigher than the setting

- A diaphragm which opens the valve when the pressuredecreases in the combustion chamber

- A guiding sleeve which supports the diaphragm

- An outlet union (to drain collector).

6.61FUEL SYSTEM

ARRIUS 1


Training Notes

COMBUSTION CHAMBER DRAIN VALVE

GUIDINGSLEEVE

DIAPHRAGMType

Diaphragm

Closing pressure35 - 40 kPa (5 - 5.8 PSI)

for N1 approx. 50%

VALVEOPEN

OUTLETUNION

FUEL

FUEL(to drain collector)

AIR PRESSURE(from combustion

chamber)

VALVECLOSED

UNION

ENGINE SHUT-DOWN ENGINE RUNNING

6.62FUEL SYSTEM


ARRIUS 1

Edition: May 2006

Training Notes

FUEL PIPES

Left front view

- Pipe from valve assembly to main manifolds

- Start injection manifold

- Main injection manifold

- Pipe from HP pump unit to valve assembly

- Drain union

- LP pump drain

- Drain of the HP pump and metering unit

- Fuel inlet union

- Pipe from stop electro-valve to HP pump

- Pressure transmitter pipe.

Right rear view

- Start injection manifold

- Air pipe for the ventilation of start injectors

- Combustion chamber drain valve

- Main injection manifolds.

6.63FUEL SYSTEM

ARRIUS 1


Training Notes

FUEL PIPES

PRESSURETRANSMITTER PIPE

PIPE FROMSTOP ELECTRO-VALVE

TO LP PUMP

FUEL INLETUNION

DRAINUNION

HP PUMP PIPE TOVALVE ASSEMBLY

DRAIN OF THE HP PUMPAND METERING UNIT

LP PUMPDRAIN

FWD

MAIN INJECTIONMANIFOLD

AIR PIPE FOR THEVENTILATION OFTHE INJECTORS

COMBUSTION CHAMBERDRAIN VALVE

STARTINJECTION/VENTILATION

MANIFOLD

PIPE FROM VALVEASSEMBLY TO

MAIN INJECTORS

FWD

7.1CONTROL SYSTEM

ARRIUS 1


Training Notes

7 - CONTROL SYSTEM

- Control system ....................................................... 7.2

• General .............................................................. 7.2• Description ........................................................ 7.4• Operation .......................................................... 7.6

- Digital Control Unit (77-30-01)............................. 7.34

• General .............................................................. 7.34• Functional description ..................................... 7.36 to 7.39


7.2CONTROL SYSTEM


ARRIUS 1

Edition: May 2006

Training Notes

CONTROL SYSTEM - GENERAL

Functions

The control system is designed to automatically adapt theengine to the aircraft power requirements whilst remainingwithin defined limits.

The main functions of the control system are the following:

- Start control

- Speed control and miscellaneous limitations

- Manual control

- Overspeed protection

- Fault monitoring and processing.

Position

The control system components are located on the engineand on the aircraft.

The DCU is supplied by the engine manufacturer butinstalled in the aircraft.


- DCU type: single channel digital electronic

- Manual control type: mechanical

- Electrical supply: redundant.

Main components

- Digital Control Unit (DCU)

- Engine (engine and systems)

- Aircraft: various systems (control, indication, supply).

7.3CONTROL SYSTEM

ARRIUS 1


Training Notes

CONTROL SYSTEM - GENERAL

AIRCRAFT(various systems)

ENGINE(engine and systems)

MAIN FUNCTIONS

- Start control

- Speed control and miscellaneous limitations

- Manual control

- Overspeed protection

- Fault monitoring and processing

DIGITAL CONTROL UNIT(DCU)

7.4CONTROL SYSTEM


ARRIUS 1

Edition: May 2006

Training Notes

CONTROL SYSTEM - DESCRIPTION

This part briefly describes the whole control system : theDCU inputs and outputs, the Digital Control Unit, theaircraft and engine systems.

DCU inputs and outputs

Inputs from the aircraft

- Logic inputs- Analog inputs.

Inputs from the engine

- Sensors (N1 and N2 rotation speeds, P3 air pressure,thermocouples, fuel metering unit resolver).

Outputs to the aircraft

- Logic outputs (indicating lights, relays)- Serial data link.

Outputs to the engine

- Accessories (electro-valve, fuel metering unit).

Digital Control Unit (DCU)

The DCU is a single channel, digital controller.

It is installed in the aircraft cargo compartment.

The DCU is of modular design and includes a controldigital part and a power turbine overspeed protection partof analog technology.

The DCU is electrically supplied from the 28 V aircraftsupply circuit and from the engine driven alternator.

Aircraft and engine systems

Various aircraft and engine systems are connected to thecontrol system.

These systems are dealt with in corresponding chapters.

7.5CONTROL SYSTEM

ARRIUS 1


Training Notes

CONTROL SYSTEM - DESCRIPTION

CONTROLSYSTEM

POWER TURBINEOVERSPEEDPROTECTION

(analog)

ALTERNATOR

SUPPLY

LOGIC INPUTS

AIRCRAFT ENGINE

DIGITAL CONTROL UNIT

ENGINE ACCESSORIES(electro-valve, fuelmetering unit, sensors ...)

LOGIC OUTPUTS(indicating lights, relays)

28V AIRCRAFTSUPPLY CIRCUIT

SENSORS(rotation speed, air pressure,thermocouples ...)

SERIAL DATA LINK

ANALOG INPUTS(T1 probe, collective pitch,

rudder control bar, trims)

7.6CONTROL SYSTEM


ARRIUS 1

Edition: May 2006

Training Notes

CONTROL SYSTEM - OPERATION (1)

GENERAL PRINCIPLES

This part is an introduction to the operation of the controlsystem.

Prior to dealing with the various functions, it is worthremembering the engine configuration and the installationrequirements.

Engine configuration

The engine includes a gas generator which providesmechanical power to a power turbine which is connectedto a receiver.

The gas generator (compressor, combustion chamber,turbine) has its operating point defined by the air flow, thefuel flow, the rotation speed and the turbine entrytemperature. The only available physical parameter forcontrol purposes is the fuel flow injected into thecombustion chamber.

The power turbine has its operating point defined by thebalance between the power provided by the gas generatorand the power required to drive the helicopter rotor; that isto say the rotation speed and the torque.

Installation requirements

We can consider the receiver requirements (helicopter)and the engine requirements.

The helicopter requirements are the following:

- A rotor rotation speed (NR) adapted (i.e.: almost constantin all operating conditions and whatever the load applied)

- A max. torque (C) of the power shaft (max. limit imposedby the mechanical transmission and mainly by the maingearbox of the helicopter).

The engine requirements are the following:

- A power turbine rotation speed (N2) maintained withingiven limits (in fact, almost constant because it isconnected to the helicopter rotor). An overspeedprotection is also required in case of failure of thetransmission shaft for example

- The gas generator rotation speeds (N1)• Max. limit imposed by the rotating assembly strength.• Min. speed imposed by critical speeds.

- Turbine entry max. temperature (max. limit imposed bythe hot section strength and particularly by the turbineblades)

- Fuel flow (Q)• Max. limit which corresponds to a power stop• Min. limit to avoid flame-out• Variation limit in time (∆Q/∆T) to avoid compressor

surge.

7.7CONTROL SYSTEM

ARRIUS 1


Training Notes

GENERAL PRINCIPLESCONTROL SYSTEM - OPERATION (1)

Air flow G Gas

N1 speed

COMBUSTIONCHAMBER

N2 speed

Torque C

Maingearbox

FUELCONTROL UNIT

DIGITALCONTROL UNIT

Fuelflow Q

Turbine entrytemperature TET

COMPRESSOR

GAS GENERATOR POWER TURBINE RECEIVER

REQUIREMENTS

- NR N2- Max. C- N1 Limits- TET- Q

INPUT SIGNALS

OTHER FUNCTIONS (code display, ∆N1,indicating lights, accessory control ...)

Compressor outletpressure P3

TURBINENR

7.8CONTROL SYSTEM


ARRIUS 1

Edition: May 2006

Training Notes


MAIN FUNCTIONS OF THE CONTROL SYSTEM

This part describes in a general way the miscellaneousfunctions of the control system: start control, speed control,manual control, twin-engine configuration, overspeedprotection, monitoring and fault processing.

Start control

The start control function is to obtain a safe start of theengine in all operating conditions.

It includes:- The fuel flow control during starting- The idle speed control- The acceleration up to the nominal speed.

Speed control

Its main function is to maintain the power turbine rotationspeed constant by metering the fuel flow.

The control loop ensures in fact the power turbine rotationspeed control and various limitations:

- Speed limitation of the gas generator- Acceleration and deceleration control- Overtorque limitation in transient conditions- Fuel flow limitation.

Manual control

This function ensures a manual control in case of a controlsystem failure.

The control is ensured by a fuel valve actuated by thecockpit throttle lever.

Twin-engine configuration

The control system takes into account the twin-engineconfiguration (synchronization) and the case of one enginefailure.

Overspeed protection

The power turbine overspeed protection systemautomatically shuts down the engine when the overspeedthreshold is reached.

Monitoring and fault processing

The control system also ensures engine monitoring andfault processing.

7.9CONTROL SYSTEM

ARRIUS 1


Training Notes

MAIN FUNCTIONS OF THE CONTROL SYSTEMCONTROL SYSTEM - OPERATION (2)

CONTROL

SYSTEM

Q

- N2 speed

- N1 speed

- Acceleration / deceleration

- Fuel flow

MONITORING ANDFAULT PROCESSING

MANUAL CONTROL

TWIN-ENGINE CONFIGURATION

OVERSPEED PROTECTION

STARTING

- Fuel flow

- Idle speed

- Acceleration

SPEED

METERINGVALVE

7.10CONTROL SYSTEM


ARRIUS 1

Edition: May 2006

Training Notes


START CONTROL

The start control includes: the fuel flow control duringstarting control, the N1 idle control and the accelerationcontrol.

Starting control

This flow control ensures rapid starting (N1 accelerationup to 68%) without overheat in all operating conditions.

The fuel flow Q injected into the combustion chamber isequal to (Q1+Q2)-∆Q

Thus, the fuel flow Q* datum is controlled as a function ofdetermined laws:

- Q1 basic flow law. Flow determined to obtain ignitionas a function of:

• the t1 air temperature• the t4.5 residual temperature

- Q2 start flow law. Flow determined to obtain theacceleration as a function of:

• the N1 rotation speed• a k factor which varies as a function of the atmospheric

pressure P0

- ∆Q flow correction law. Fuel flow correction as afunction of:

• the t4.5• the t4.5* datum which varies according to the N1

rotation speed

- Flow limitation law. Corrected fuel flow limited by amin. and a max. flow value.

7.11CONTROL SYSTEM

ARRIUS 1


Training Notes

START CONTROLCONTROL SYSTEM - OPERATION (3)

t4.5*

648

472

0 55 76N1

t4.5

N1

t4.5

t1

P0

N1 (%)

68

0

=∆t4.5*

t4.5*

=Q1+

Q2

0 160 670

255

65

∆Q

∆t4.5

Q

0 68N1

Q2

30

15 61.5N1

P0

k

1

0 1023

Q1

39

30

-60 -50 0 +60t1

t4.5 < 50°C

t4.5 > 50°Ct4.5 > 50°C

FUELFLOW Q*

FLOW LIMITATION LAW

Q2 STARTFLOW LAW

Q1 BASICFLOW LAW

t4.5 DATUM (limit)AS A FUNCTION OF N1

∆Q FLOWCORRECTION LAW

∆Q

N1 idle

Time

7.12CONTROL SYSTEM


ARRIUS 1

Edition: May 2006

Training Notes


START CONTROL (CONTINUED)

N1 idle control

To start the engine a 3-position selector is moved to eitherTraining or Flight.

Starting in the Training position, the engine will start andaccelerate to N2 idle (90% N2), with N1 approx. 75%.

Starting in the Flight position, the engine will start andaccelerate to 100% N2, with N1 approx. 80%.

1 - If for any reason (eg. rotor brake applied), the N2 speeddoes not accelerate sufficiently, the system will maintainthe engine at 68% N1 to avoid overtorque.

Acceleration control

2 - Acceleration up to N2 idle ensured by the speedcontrol loop as a function of determined laws:

• N2 speed control law: the N2 controller provides avariable N1* datum. The N1* datum varies according tothe actual acceleration of the power turbine (law ∆N1/∆N2; to avoid overtorque).

• N1 speed control law: it determines the Q* flow datumso that the actual N1 is equal to the N1* datum providedby the control law N2.

3 - N2 idle: at the end of the acceleration, the N2 isstabilised at a controlled speed as function of determinedlaws:

• N2 speed control law: the actual N2 speed is comparedwith the N2* idle datum (approx. 90%). The N2 controllerprovides an N1* datum

• N1 speed control law: the actual N1 speed is comparedwith the N1* datum to elaborate the Q* flow datum.

4 - Acceleration up to the N2 nominal speed: Theacceleration is commanded when the mode selector is setto the "Flight" position: the two engines have the sameacceleration rate.

5 - The system stabilises the engine at 100% N2

6 - Training mode control: if the selector is moved fromFlight to Training, the engine will decelerate to 90% N2.

7 - If the other engine stops the control unit will maintaina minimun N2 of 85% (if the pilot increases the collectivepitch).

7.13CONTROL SYSTEM

ARRIUS 1


Training Notes

START CONTROL (CONTINUED)CONTROL SYSTEM - OPERATION (4)

85

1N1 (%)

96

70

90

N2 (%)

N1 (%)

time

N2 = 100%

N2 = 90%

N1

N1* = 68% if N2 < threshold

N2 Q

Q

N2*

N1*

2

3

4

5

6

7

N1

Q*

Flight80

N2 idle75

N1 idle68

0

1 N1 IDLE

N1 Controlunit

2ENGINE ACCELERATION: RAMPS OF N1* ACCORDING TOACTUAL N2

3 N2 IDLE: N2* DATUM (N2 approx. 90%)

4 ACCELERATION: N2* RAMP

5 N2 NOMINAL: N2* DATUM (N2 = 100%)

6DECELERATION: N2* RAMP WHEN PASSING FROM FLIGHT TO TRAINING

7 TRAINING MODE CONTROL

N1 Controlunit

Fuel meteringunit

Fuel meteringunit

N2 Controlunit

N1 CONTROL

N2 CONTROL

7.14CONTROL SYSTEM


ARRIUS 1

Edition: May 2006

Training Notes


SPEED CONTROL - GENERAL

The speed control loop mainly includes:

- An N2 power turbine speed control unit

- An N1 gas generator speed control unit

- A fuel flow metering unit (Q).

The power turbine control unit measures the actual speed(N2) and a datum provided by the collective pitch. Itdetermines a speed datum (N1*) according to the measureddifference.

The gas generator control unit measures the speed datum(N1*) and the actual speed (N1) and determines a flowdatum in order to adapt the gas generator to the operatingconditions.

The fuel metering unit receives the flow datum (Q*) andcalculates the actual flow (Q).

N1/N2 relation (control unit static droop)

In this type of control system, the N1 speed is madeinversely proportional to N2. The N1/N2 relation illustratesthis proportionality and the N2 variation is called "staticdroop" (St).

The static droop ensures the system stability, but it is notacceptable because the helicopter rotor requires a constantspeed.

As the largest load variations come from the collectivepitch, a link between the control unit and the collectivepitch compensates the static droop. Furthermore, thedetection phase is advanced (this explains the name"anticipator") to reduce the response time.

Static droop compensation

The "static droop compensation" curve illustrates thestatic droop lines for different collective pitch positions(angles).

In operation, points 1, 2 and 3 are obtained and the staticdroop is then compensated; this means: constant powerturbine speed (and therefore rotor speed) in all operatingconditions.

In transient operation, the power turbine speed varies, butthe control unit operates quickly to return the speed to itsnominal value, within the value of the static droop.

7.15CONTROL SYSTEM

ARRIUS 1


Training Notes

SPEED CONTROL - GENERALCONTROL SYSTEM - OPERATION (5)

N2 Speed

COLLECTIVE PITCH

N1

N1

N1

N2

N2

N2

N1

N2

1

3

2

Static droop

N1 / N2 RELATION CURVE(control unit static droop)

STATIC DROOP COMPENSATION CURVE

high pitch

medium

pitch

low pitch

Fuel meteringunit

Flow Q

Gas generatorcontrol unit

Q* flowdatum

N1 Speed

N2* speed datum

SPEED CONTROL LOOP

N1* speeddatum

Power turbinecontrol unit

COLLECTIVE PITCH

7.16CONTROL SYSTEM


ARRIUS 1

Edition: May 2006

Training Notes


SPEED CONTROL - CONTROL LOOP

We can distinguish the following functional assemblies:

- The N2 control unit (speed control unit, acceleration anddeceleration limiter, torque limiter, N1 min. and max.stops)

- The N1 control unit (speed control unit, flow limiter)

- The fuel metering unit.

N2 control unit

- Determines an N2* datum as a function of the rotorcollective pitch and of the tail rotor pitch α0, of the"trims" α1 and of an N2

0 datum speed

- Compares this datum to the actual N2 and calculates thedifference

- Processes this difference with a proportional control

- Provides an N1* datum

- Controls the acceleration and deceleration, limits thetorque (the min. selector selects the lowest signal) andensures the N1 max. and min. stops.

Anticipator

A signal proportional to the collective pitch angle, calledXCP, is added to the N1* datum.

N1 control unit

- Compares the N1* datum to the actual speed N1

- Determines a Q* flow datum limited by the max. andmin. flow conditions.

Fuel metering unit

- Ensures the Q* flow signal conversion

- Outputs the signal to the stepper motor of the fuelmetering valve.

Speed control - Example of transient condition

When the collective pitch increases the XCP signal givesan initial increase of the N1* datum. The N2 speed drops.The N2 control unit detects the drop and calculates a newN1* datum. The N1 control unit processes this datumaccording to certain limitations (acceleration, torque,flow…) and determines a Q* flow datum which istransmitted to the metering unit. The flow increases, theN1 speed increases, the N2 speed returns to its nominalvalue.

7.17CONTROL SYSTEM

ARRIUS 1


Training Notes

SPEED CONTROL - CONTROL LOOPCONTROL SYSTEM - OPERATION (6)

N1XCP

N1*

N20

P

N2

N2*

∆N2

α1

α0

N1* N1*

N1*

Q*

Q*

Q

FUEL METERINGUNIT Q

N1 CONTROL UNIT

N2 CONTROL UNIT

Control unit

P

I

: Proportional

: Integral

Max. N1Min. N1

Meteringunit

Minimum selector

Acceleration /DecelerationTorque

Max. QMin. Q

timePower turbine

speed N2

Fuel flow Q

Load C

Gas generatorspeed N1

Signals

α0: Rotor collective pitch and rudder control barα1: Balancing and rotor trims*: DatumN20: N2 reference = 100%XCP: Collective pitch

time

time

time

7.18CONTROL SYSTEM


ARRIUS 1

Edition: May 2006

Training Notes


SPEED CONTROL - MISCELLANEOUS LIMITS

Beyond the speed control, the N2 speed control unitensures some limitations. It acts on the N1* datum transfer:

- Acceleration and deceleration limitations

- Transient overtorque limitation

- N1 speed limitation.

Acceleration and deceleration limitations

These limitations ensure a protection against:

- Compressor surge in case of rapid acceleration (collectivepitch increase)

- Flame out in case of rapid deceleration (collective pitchdecrease).

The system limits the variation rate of the N1* datum as afunction of the time t (dN1*/dt).

The max. rating is comprised between + 13%/s inacceleration and - 25%/s in deceleration and depends onthe P0 atmospheric pressure. It decreases when the pressuredecreases (slower acceleration and deceleration).

Overtorque limitation

This limitation avoids torque overshoot due to the dynamicsof the control loop during transient load increase.

The overtorque limitation limits the variation rate of N1*datum as follows:

From the input signals (N2* - N2 difference) and N1*delivered by the control unit, the overtorque limitation unitanalyses the direction of the N2* - N2 variation:

- If the change is negative: no effect

- If the change is positive: a dN1*/dt datum is calculatedas a function of dN2/dt.

7.19CONTROL SYSTEM

ARRIUS 1


Training Notes

SPEED CONTROL - MISCELLANEOUS LIMITSCONTROL SYSTEM - OPERATION (7)

N1*

N1*

t1P0

N1* N1*

(dN2 / dt) N1* N1* P0

N1* N1*

N2

dN2 / dt < 0 dN2 / dt > 0

N1*

A B

ACCELERATION / DECELERATION CONTROLAND OVERTORQUE LIMITATION

Minimumselector

N1 limitation(max. N1, min. N1)

Controls

Overtorquelimitation

Acceleration anddeceleration

limitation

Acceleration rate

time

High P0

Deceleration ratetime

Low P0

OVERTORQUE LIMITATION

A: - N2 speed drop- N1* increase without overtorque control and under acceleration control (acceleration rate law applies here)

B: - Return to N2 nominal speed- N1* acceleration with overtorque control

- Transient phase without overtorque control

time

time

Low P0

High P0

7.20CONTROL SYSTEM


ARRIUS 1

Edition: May 2006

Training Notes


SPEED CONTROL - MISCELLANEOUS LIMITS(CONTINUED)

N1 speed limitation

The N1 speed limitation system provides the max. ratingwhile protecting the engine. The ratings are selected by thepilot (i.e.: OEI 2 min. 30 sec. rating, training 2 min. 30 sec.rating control…). Limitation also depends on theatmospheric conditions (P0 pressure, t1 temperature).

max. N1*: N1 (t1) - ∆N1 (P0)

The min. N1 speed is also limited to avoid operation atcritical ratings.

A push button on collective pitch lever selects betweenOEI 2 min. 30 sec. rating and OEI 30 min. rating.

A training-normal selector allows one engine to be selectedto training. The engine selected to training is reduced toidle (90% N2), and the other engine has its max. powerlimited to take-off power.

Flow limitation

The control ensures two fuel flow limitations:

- Max. fuel flow. This limitation is calculated as a functionof the compressor outlet pressure (P3). It is a max. powerstop.

There are in fact two stops: a max. flow stop in normaloperation and a max. flow stop in training mode

- Min. fuel flow. This limitation is calculated as a functionof the P0 atmospheric pressure in order to avoid flameout especially during rapid load decrease.

7.21CONTROL SYSTEM

ARRIUS 1


Training Notes

SPEED CONTROL - MISCELLANEOUS LIMITS (CONTINUED)CONTROL SYSTEM - OPERATION (8)

t1 (°C)

103

102

101

100

99

N1 (%)

-50 0 15 +50

1,3

0500 1013

∆N1 (%)

N1*

Q*

t1

P0

N1* N1*

(dN2 / dt) N1* N1* P0

Q*

Q*

0

0

P3

P0

P3P0

P0

OEI 2 min. 30 sec.

OEI 30 min.

T/O

MCP

t1 (°C)

N1 SPEED LIMITATION

Max. N1* = N1(t1) - ∆N1(P0)

Minimumselector

N1 limitation(max. N1, min. N1)

Controls

Overtorquelimitation

Acceleration anddeceleration

limitation

NORMAL

TRAINING

MAX. FLOW

MIN. FLOW

FLOW LIMITATION

Max. Q Min. Q

Normalconfiguration

7.22CONTROL SYSTEM


ARRIUS 1

Edition: May 2006

Training Notes


MANUAL CONTROL

This system ensures a manual control of the fuel flow. Itis used in case of a failure of the automatic control system.

In most cases, a control system failure locks the meteringvalve in its position at time of failure.

The manual control acts on a valve of the hydromechanicalcontrol unit located between the fuel pump and the meteringunit. This valve will either cause a reduction of flowthrough the main valve or allow an increased flow in by-pass of the main valve.

Control positions of the manual metering valve

- "Normal" position. Neutral position, the flow iscontrolled by the metering unit

- "Flow decrease" range. The manual metering valvereduces the section of the direct passage and thus the fuelflow

- "Flow increase" range. The fuel flow by-passes themetering unit, and thus allows the fuel flow increasewhilst limiting the flow to the "frozen" metering unit.

Flow range of the manual control

- Manual valve effect with the main metering valve fullyopen:

All the fuel flow range is open between the zero flow (-45°)and the max. flow (5°)

- Manual valve effect with the main metering valve fullyclosed:

All the fuel flow range is open between the zero flow (5°)and the max. flow (45°)

- Manual valve effect with the main metering valve lockedat any flow, at the neutral notch:

All the fuel flow range is open between the fully closedflow (-45°) and the fully open flow (45°)

- Reduction notch:

The reduction notch ensures a min. flow to avoid flame outin all conditions.

Note: An auto-manual selector is used for automaticcontrol failure training. When selected to manual,the stepper motor is frozen and the engine has to becontrolled manually.

7.23CONTROL SYSTEM

ARRIUS 1


Training Notes

MANUAL CONTROLCONTROL SYSTEM - OPERATION (9)

Q ≠ 0

Q = 0

N

Q

Q

N

Q = 0

Q

N

Man

ual v

alve

effe

ct w

ith th

e m

ain

met

erin

g va

lve

fully

clo

sed

Fuel flow

Q2(min. flow at thereduction notch)

Q1(no flow)

Man

ual v

alve

effe

ct w

ith th

e m

ain

met

erin

g va

lve

fully

ope

n

Manua

l valv

e effec

t with

themain meteri n g

valve

lock

edat

any

flow

atth

ene

utra

l not

ch

Q3(controlledmax. flow)

X(any flow)

Neutral notch rangewith no effect

(±5°)

Valve stopopen(+45°)

Valveposition (°)

CONTROL POSITIONS OF THEMANUAL METERING VALVE

FLOW RANGE OF THE MANUAL CONTROL

MANUAL DECREASE

MANUAL INCREASE

NORMAL (N)

Valve stopclosed(-45°)

7.24CONTROL SYSTEM


ARRIUS 1

Edition: May 2006

Training Notes


OVERSPEED PROTECTION

The protection against power turbine overspeedautomatically stops the engine when an overspeed thresholdis reached.

The protection system includes:

- The overspeed module of the Digital Control Unit(analog processing)

- The power turbine speed sensors

- Some control and monitoring components (aircraftoverspeed test unit)

- The stop electro-valve (to shut-off the injector fuelsupply when electrically supplied).

Operation

During starting, the system is tested at approximately 25%N2.

In normal operation, the power turbine speed is stabilisedat around 100% by the control unit (nominal speed).

In the event of an overspeed (112 +3%), the systemoperates as follows:

- Overspeed detection

- Electrical supply to the stop electro-valve (shut-downorder)

- Overspeed indication.

After the overspeed operation a specific procedure allowsthe rearming of the system.

A cross monitoring system between the two DCUs inhibitsthe operation of the overspeed protection system of theengine remaining in operation.

7.25CONTROL SYSTEM

ARRIUS 1


Training Notes

OVERSPEED PROTECTIONCONTROL SYSTEM - OPERATION (10)

112 ± 3

25

N2 (%)

t0

100

N2 PHONICWHEEL

POWERTURBINE

DIGITALCONTROL UNIT

OVERSPEEDTEST UNIT

Aircraft

SENSOR

PRINCIPLE OF THE POWER TURBINEOVERSPEED PROTECTION

OVERSPEED MODULE OF THEDIGITAL CONTROL UNIT

28V aircraftsupply

N2signals

Rearmingand test signals

Stop electro-valve

Crossmonitoring

OVERSPEED MODULE DIAGRAM

SPEED THRESHOLD DIAGRAM

SYSTEM TEST

OVERSPEED

NOMINAL SPEED

Indication

Q

STOPELECTRO-VALVE

7.26CONTROL SYSTEM


ARRIUS 1

Edition: May 2006

Training Notes


SPEED UNIT - OVERSPEED DETECTION SYSTEM

Function

The overspeed detection system stops the engine when thepower turbine rotation speed (N2) reaches a given value.

Position

The overspeed detection system is part of the speed unit.


- Analog system

- System electrically independent from the DCU

- Response time: very short.

Main components of the system (per engine)

- Two speed sensors measuring the speed of power turbineshaft

- A speed printed circuit board connected to the otherengine DCU. This printed circuit board includes amonostable relay V, a bistable relay S-S', 25% and112% detection modules and a 112% N2 oscillator

- A stop electro-valve (ECA)

- One overspeed test box for the two engines, whichincludes the TEST and REARMING push buttons andOVERSPEED (OVSP + indicating light) and ARMING(S + indicating light) indications.

Operation

Power-up

When N2 ≤ 25%, the push button and the arming indicatinglight "S" are electricaly supplied.Rearming is possible.

Overspeed test

An OVERSPEED TEST push button allows the checkingof the detection system operation.

When the TEST push button is depressed, the oscillatoroperates and simulates a 112% power turbine overspeed.

The test is inhibited at power turbine rotation speedshigher than 25%.

At each starting, when N2 > 25%, the push button and thearming indicating light "S" shut-off.

Note: The OVERSPEED and ARMING indicating lightsand the push buttons are located in the luggagecompartment.

Overspeed

The overspeed detection system monitors the N2 speedthrough two different channels.

If the signals reach the given thresholds (112 ±3% N2), thesystem opens the stop electro-valve and provides theoverspeed signal. The engine stops.

The overspeed detection system also controls the mutuallock of both engine protection loops. This lock prevents anengine being shut-down through the N2 overspeedprotection loop if the other engine has already suffered anoverspeed shut-down.

7.27CONTROL SYSTEM

ARRIUS 1


Training Notes

SPEED UNIT - OVERSPEED DETECTION SYSTEMCONTROL SYSTEM - OPERATION (11)

S V

112%

112%

25%

25%

S'

N2

N2

"S" +

- Supply of the arming signal "S" + indicating light (up to 25% of N2)- Rearming (if necessary)

SYSTEM POWER ON(N2 ≤ 25%)

- Oscillator supply 112%*- Oscillator inhibited for N2 > 25%

OVERSPEED TEST

- V monostable relay supply- S bistable relay supply- Stop electro-valve supply- Overspeed signal "OVSP" supply + indicating light- 2nd engine system inhibition

OVERSPEED(N2 = 112 ± 3%)

Oscillator

Engineshut-down

Stop electro-valve

"OVSP" +

2nd engine inhibition

Test

RearmingCircuits which are inhibited if N2>0%

7.28CONTROL SYSTEM


ARRIUS 1

Edition: May 2006

Training Notes


TWIN-ENGINE CONFIGURATION

Configuration description

The helicopter rotor is driven by the two engines throughthe main gearbox and the free wheels.

Each engine has its own control unit which includes:

- A power turbine N2 speed control unit (calculation ofthe N1* datum in relation to various parameters)

- A gas generator N1 speed control unit (metering of thefuel flow Q to keep the N1 speed constant and equal tothe N1* speed datum).

The N2 control units of the two engines receive signalsfrom the same collective pitch control ("anticipator" link).

Load sharing principle

In normal conditions, the helicopter rotor is driven by thetwo power turbines; thus:

NR = kN2 eng 1 = kN2 eng 2

The speed signals received by the two control units are thesame, so are the collective pitch signals. The control unitsthen determine identical datums which are kept constantby the fuel metering devices.

As the power is linked to the N1 speed and as the powerturbine efficiency varies very little from one turbine toanother, a good load sharing is obtained.

The N1* datums can be modified if a difference appears;in this case, the datums can be modified by the manual trimcontrol.

Operation on a single engine

In this case, the operating engine provides the power andthe other is disengaged through the free wheel. The enginespeed limit is represented by the gas generator speed; OEI2 min. 30 sec. rating.

7.29CONTROL SYSTEM

ARRIUS 1


Training Notes

TWIN-ENGINE CONFIGURATIONCONTROL SYSTEM - OPERATION (12)

Q

N2 N1

N1*

N1

N2

HELICOPTER ROTOR

Maingearbox

POWERTURBINE

N1 CONTROL UNIT N2 CONTROL UNITN2 CONTROL UNIT

FREE WHEELCOLLECTIVEPITCH

CONTROL PRINCIPLE

Max.

Min.

OPERATING POINTON ONE ENGINE

(same power suppliedby a single engine)

OPERATING POINTON TWO ENGINES

CONTROL DIAGRAM

GASGENERATOR

7.30CONTROL SYSTEM


ARRIUS 1

Edition: May 2006

Training Notes


TRAINING MODE

This system is designed to simulate an engine failure.

During flight, the failure of one engine is simulated byswitching the "STOP/TRAINING/FLIGHT" selector ofthe chosen engine to the "TRAINING" position. Then, theengine is controlled in training idle mode (90% N2). Thus,the power turbine is disengaged from the helicopter maingearbox. The other engine operates in the "TRAININGFLIGHT" (Training OEI) mode.

The "TRAINING FLIGHT" mode is identical to the"FLIGHT MODE" but uses derated N1 stops in order toavoid the use of the OEI ratings.The working rating is thenthe MTOP.

However, the engine operating in the training idle mode isable to deliver the required power in the event of a realfailure of the other engine. The speed is controlled at atraining speed of 90% N2 and the anticipator function iscancelled.

7.31CONTROL SYSTEM

ARRIUS 1


Training Notes

TRAINING MODECONTROL SYSTEM - OPERATION (13)

DCUENGINE 1

ENGINE 1REDUCE TO

90% N2

ENGINE 2LIMITED TO

MAX. TAKE-OFF POWER

"TRAINING"indication DCU

ENGINE 2

FLIGHT

TRAINING

STOP

FLIGHT

TRAINING

STOP

7.32CONTROL SYSTEM


ARRIUS 1

Edition: May 2006

Training Notes


MONITORING AND FAILURE PROCESSING

The control system ensures a continuous monitoring (builtin test equipment) of various parameters: circuit continuity,signal validity, tests before starting, supply monitoring.

There are three predetermined levels of failure: majorfailure, minor failure and loss of redundancy.

Major failure

In case of a major failure, the stepper motor is "frozen" andthe manual control valve can be used (e.g.: metering unitfailure, loss of two N1 or N2 signals, loss of two powersupplies, DCU failure).

Minor failure

In case of a minor failure, the stepper motor operatesnormally and the control system operates from a recoverylaw (e.g.: loss of one sensor without redundancy).

Loss of redundancy

In the event of loss of redundancy, the system continues innormal control and maintenance action is necessary afterflight (e.g.: loss of one N1 or N2 sensor, loss of one powersupply).

Recovery laws

In case of defective operation or hardware failures, theDigital Control Unit can continue to operate, but only fromrecovery values.

The Digital Control Unit uses recovery laws for thefollowing failures:

- P0 failure

- T1 failure

- t4.5 failure

- P3 failure

- Collective pitch failure

- Trim failure.

7.33CONTROL SYSTEM

ARRIUS 1


Training Notes

MONITORING AND FAILURE PROCESSINGCONTROL SYSTEM - OPERATION (14)

- P0 failure- T1 failure- t4.5 failure- P3 failure- Collective pitch failure- Trim failure

RECOVERY LAWS (minor failures)

SUPPLY

INTERNALCHECKS


EXTERNALCHECKS

- Content of memories- Calculations- Internal supply- ...

- Continuity- Sensor insulation- Lack or evidence of signals- …

- Major failure- Minor failure- Loss of redundancy

OPERATION PRINCIPLE

WARNINGS

7.34CONTROL SYSTEM


ARRIUS 1

Edition: May 2006

Training Notes

DIGITAL CONTROL UNIT - GENERAL

Function

The Digital Control Unit controls and monitors the engineoperation.

Position

It is installed in the helicopter baggage compartment.


- DCU type: single channel, digital electronic

- Design: modular

- Electrical supply: redundant.

Main components

The Digital Control Unit includes the following mainunits :

- Interconnection unit

- Power supply unit

- Speed unit

- Output unit

- Processor unit

- Input unit

- Connectors

- Anti-vibration mountings

- Earth braid mounting flange.

The 6 units are attached by means of tie bolts and pins.

Identification

There is an identification plate located on the front face ofthe interconnection unit.

7.35CONTROL SYSTEM

ARRIUS 1


Training Notes

DIGITAL CONTROL UNIT - GENERAL

CONNECTORSTIE BOLTPIN

MOUNTING(with anti vibration device)

SPEEDUNIT

OUTPUTUNIT

PROCESSORUNIT

INPUTUNIT

DIGITALCONTROL UNIT

(helicopter baggage compartment)

DCU typeSingle channel

digital electronic

DesignModular

Electrical supplyRedundant

IDENTIFICATIONPLATE

INTERCONNECTIONUNIT

POWER SUPPLYUNIT

EARTH BRAIDMOUNTING FLANGE

7.36CONTROL SYSTEM


ARRIUS 1

Edition: May 2006

Training Notes

DIGITAL CONTROL UNIT - FUNCTIONALDESCRIPTION (1)

DCU inputs

From the aircraft

- Overspeed TEST and REARM selector

- FLIGHT - TRAINING - STOP selector

- OEI 2 min. 30 sec. - OEI 30 min. selector

- AUTO - MANUAL selector

- Collective pitch and tail rotor pitch α0

- Trims (balance and rotor) α1

- Cross monitoring (overspeed)

- Serial data link.

From the engine

- T1 temperature probe

- N1 speed sensors

- N2 speed sensors

- P3 air pressure sensor

- t4.5 thermocouples

- Fuel metering unit resolver.

Power supply

- 28 V Aircraft supply circuit

- Engine alternator.

7.37CONTROL SYSTEM

ARRIUS 1


Training Notes

DCU INPUTSDIGITAL CONTROL UNIT - FUNCTIONAL DESCRIPTION (1)

- SERIAL DATA LINK

- N1 SPEED SENSORS

- T1 TEMPERATURE PROBE

- FUEL METERING UNIT RESOLVER

- t4.5 THERMOCOUPLES

- P3 AIR PRESSURE SENSOR

ENGINE

DIGITALCONTROL UNIT

(ENGINE 1)

- OVERSPEED TEST

SUPPLY

ALTERNATOR

- OVERSPEED REARMING

- FLIGHT - TRAINING - STOP SELECTOR

- OEI 2 min. 30 sec. - OEI 30 min. SELECTOR

- AUTO - MANUAL SELECTOR

- TRIMS α1

DIGITALCONTROL UNIT

(ENGINE 2)

- N2 SPEED SENSORS

AIRCRAFT

28V AIRCRAFTSUPPLY CIRCUIT

- COLLECTIVE PITCH AND TAIL-ROTOR PITCH α0

7.38CONTROL SYSTEM


ARRIUS 1

Edition: May 2006

Training Notes

DIGITAL CONTROL UNIT - FUNCTIONALDESCRIPTION (2)

DCU outputs

To the aircraft

- ∆N1 indicator

- Indicating lights• Overspeed• Overspeed armed• Contingency power• Minor / redundancy failures (amber GOV)• Major failure (red GOV)• Training.

- Start control relay

- Serial data link

- Cross monitoring.

To the engine

- Stop electro-valve

- Fuel metering unit

- P3 air pressure sensor

- T1 probe.

7.39CONTROL SYSTEM

ARRIUS 1


Training Notes

DCU OUTPUTSDIGITAL CONTROL UNIT - FUNCTIONAL DESCRIPTION (2)

ENGINE

DIGITALCONTROL UNIT

(ENGINE 1)

DIGITALCONTROL UNIT

(ENGINE 2)

AIRCRAFT

STOP ELECTRO-VALVE

- FUEL METERING UNIT

- P3 AIR PRESSURE SENSOR

- T1 PROBE

- ∆N1 INDICATOR

- OVERSPEED INDICATING LIGHT

- OVERSPEED ARMED INDICATING LIGHT

- CONTINGENCY POWER INDICATING LIGHT

- MINOR/REDUNDANCY FAILURES

INDICATING LIGHT (amber GOV)

- MAJOR FAILURE

INDICATING LIGHT (red GOV)

- TRAINING INDICATING LIGHT

- START CONTROL RELAY

- SERIAL DATA LINK

8.1MEASUREMENT AND INDICATING SYSTEMS

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Training Notes

8 - MEASUREMENT ANDINDICATING SYSTEMS

- Measurement and indicating systems ........................................ 8.2- Speed measurement and indicating system ............................... 8.4

• N1 speed sensor (77-10-01)........................................................ 8.6• N2 speed sensors (77-10-02) ...................................................... 8.10

- Gas temperature measurement and indicatingsystem (77-20-01) .......................................................................... 8.14• Thermocouple probes and t4.5 conformation box (77-10-03) .. 8.16

- Torque measurement and indicating system ............................. 8.20• Torque transmitter (77-10-03) ........................................................ 8.24

- Miscellaneous indications ............................................................ 8.26• Indicators.................................................................................... 8.26• ∆N1 measurement and indicating system................................ 8.28• Display system............................................................................ 8.30 to 8.33




ARRIUS 1

Edition: May 2006

Training Notes

MEASUREMENT AND INDICATING SYSTEMS

Functions

The measurement and indicating system provides thefollowing functions:

- It allows to check that the engine is operating withindetermined limits

- It signals faults or abnormal changes of parameters

- It permits the checking of certain operating phases.

Miscellaneous indications

- Electrical measurement system directly connected toindicators or through the engine electronic control unit

- We can distinguish:• The operating parameters (N1, ∆N1 and torque)• The monitoring parameters (N2, t4.5, oil pressure

and temperature, miscellaneous indications).

Miscellaneous measurement and indicatingsystems

- N1 gas generator rotation speed

- N2 power turbine rotation speed

- t4.5 gas temperature

- Engine torque

- Lubricating system (refer to chapter "OIL SYSTEM")

- Miscellaneous (indicating lights and monitoring).


ARRIUS 1


Training Notes

MEASUREMENT AND INDICATING SYSTEMS

FUNCTIONS

- To ensure that the engine operates within determined limits

- To signal a fault or an abnormal change of parameters

- To check certain operating phases

MISCELLANEOUS(indicating lightsand monitoring)

N1SPEED

t4.5 GASTEMPERATURE

N2SPEED

LUBRICATINGSYSTEM

ENGINETORQUE



ARRIUS 1

Edition: May 2006

Training Notes

SPEED MEASUREMENT AND INDICATINGSYSTEM

Function

This system measures the rotation speeds of the gasgenerator (N1) and the power turbine (N2).


- Type: phonic wheels and electromagnetic sensors

- Sensor signals: frequency proportional to the rotationspeed

- Indication: digital in percentage.

Main components

- N1 speed sensor

- N2 speed sensors

- Connections with the DCU

- Connections with the indicators.

Description

Refer to sensors and to aircraft publications.

General operation

The gas generator rotation speed (N1) signal is used for:

- Engine control (starting, speed control loop)

- Indication (N1 and ∆N1).

The N1 speed is an operating parameter as it reflects theengine power and serves to determine the limit ratings.

The power turbine rotation speed (N2) signal is used for:

- Engine control (speed control loop and overspeedprotection)

- Indication (associated with the NR rotation speedindication).


ARRIUS 1


Training Notes

SPEED MEASUREMENT AND INDICATING SYSTEM

CONTROL

STARTING

SPEEDCONTROL LOOP

OVERSPEEDPROTECTION

N1gas generatorrotation speed

N2 power turbinerotation speed

+NR rotor

rotation speed

∆N1indicator

N1 SENSOR, Y2

FirewallENGINE

N1 SENSOR, Y1

N1 SENSOR, Y3

NR signal

DIGITAL CONTROL UNITCOCKPIT

N2 SENSOR, X1

N2 SENSOR, X2

N2 SENSOR, X3

N2 SENSOR, Y1

N2 SENSOR, Y3



ARRIUS 1

Edition: May 2006

Training Notes


N1 SPEED SENSOR - GENERAL

Function

The N1 speed sensor measures the rotation speed of the gasgenerator rotating assembly.

Position

- Upper part of the reduction gearbox.


- Type: electromagnetic

- Quantity: 1 triple sensor (signals: Y1, Y2 and Y3)

- Phonic wheel:• Quantity: 1 triple

2 wheels with 41 teeth1 wheel with 37 teeth

• On the starter drive gear

- Signals at 100% N1:• Y2 and Y3: 7844 Hz for 11479 RPM• Y1: 7078.7 Hz for 11479 RPM.

Main components

- Starter drive gear

- Triple phonic wheel

- Triple electromagnetic sensor

- Electrical connector (connections with the DCU and theN1 indicator).


ARRIUS 1


Training Notes

N1 SPEED SENSOR - GENERALSPEED MEASUREMENT AND INDICATING SYSTEM

TypeElectromagnetic

Quantity1 triple sensor

(Y1, Y2 and Y3)

Phonic wheel- Quantity: 1 triple

2 wheels with 41 teeth1 wheel with 37 teeth- Starter drive gear

Signals (100% N1)Y2 and Y3: 7844 Hz for 11479 RPM

Y1: 7078.7 Hz for 11479 RPM

ELECTRICALCONNECTOR

- Connection with the DCU for Y1 and Y3- Connection with the indicator for Y2

N1 SENSOR

TRIPLEPHONIC WHEEL

TRIPLE N1SENSOR

STARTER DRIVEGEAR



ARRIUS 1

Edition: May 2006

Training Notes


N1 SPEED SENSOR - DESCRIPTION - OPERATION

Description

The measurement and indicating system includes:

- A triple phonic wheel (two wheels with 41 teeth and onewith 37 teeth)

- A triple electromagnetic sensor which includes threemagnetic cores and coils.

The gap between the phonic wheel and the sensor is0.5 mm (0.018 inch). The gap is adjustable with a laminatedshim.

The three sensors are located in a single casing. Theelectrical connection is made through a 12 pin connector.

Operation

The phonic wheel rotates in front of the sensor andproduces a pseudo sinusoidal alternating voltage.

The alternating voltage frequency is proportional to thegas generator rotation speed and to the number of phonicwheel teeth.

Phonic wheel Gas generator

F (Hz) =teeth number (d) x rotation speed

60

The Y1 and Y3 sensors are connected to the DigitalControl Unit for the control system operation and the splitindication.

The Y2 sensor is connected to the speed indicator installedin the cockpit.


ARRIUS 1


Training Notes

N1 SPEED SENSOR - DESCRIPTION - OPERATIONSPEED MEASUREMENT AND INDICATING SYSTEM

Y1 & Y3

Y2

12 PINCONNECTOR

ELECTROMAGNETICSENSOR

PHONIC WHEEL

PRINCIPLE OF SPEED MEASUREMENT

SCHEMATIC DIAGRAM

DESCRIPTION

(F)

GapMagnetic

core

Coil

N F = N x d60

Gap = 0.5 mm (0.018 inch)

PHONICWHEEL (d)

Y3 Y2 Y1

COCKPIT

STARTERDRIVE GEAR

DIGITALCONTROL UNIT(control system)

∆N1INDICATOR



ARRIUS 1

Edition: May 2006

Training Notes

Main components

- Power turbine shaft

- Triple phonic wheel

- Triple electromagnetic sensors

- Electrical connectors (connections with the DCU andthe N2 indicator).


N2 SPEED SENSORS - GENERAL

Function

The N2 speed sensors measure the rotation speed of thepower turbine rotating assembly.

Position

- Front face of the reduction gearbox casing, around thefront part of the power turbine shaft.


- Type: electromagnetic sensor

- Quantity: 2 triple sensors (signals: X1, X2 and X3; Y1,Y2 and Y3)

- Phonic wheel:• Quantity: 1 triple

2 wheels with 16 teeth1 wheel with 13 teeth

• Fitted at the end of the power turbine shaft

- Signals at 100% N2:• X1, X2, Y1 and Y2: 12116.8 Hz for 45438 RPM• X3 and Y3: 9844.9 Hz for 45438 RPM.


ARRIUS 1


Training Notes

N2 SPEED SENSORS - GENERALSPEED MEASUREMENT AND INDICATING SYSTEM

TypeElectromagnetic

Quantity2 triple sensors

(X1, X2 and X3 ; Y1, Y2 and Y3)

Phonic wheel- Quantity: 1 triple

2 wheels with 16 teeth, 1 wheel with 13 teeth- Fitted at the end of the power turbine shaft

Signals (100% N2)

X1, X2, Y1 and Y2: 12116.8 Hz for 45438 RPMX3 and Y3: 9844.9 Hz for 45438 RPM

N2SENSORS

REDUCTION GEARBOXCASING

TRIPLE N2SENSORS

TRIPLEPHONIC WHEEL

POWER TURBINESHAFT

ELECTRICALCONNECTORS

- Connection with the DCU- Connection with the N2 indicator



ARRIUS 1

Edition: May 2006

Training Notes


N2 SPEED SENSORS - DESCRIPTION - OPERATION

Description

The measurement and indicating system includes:

- A triple phonic wheel (two wheels with 16 teeth and onewith 13 teeth)

- Two triple electromagnetic sensors which include, each,three magnetic cores and coils.

The gap between the phonic wheel and the sensor is0.5 mm (0.018 inch). The gap is adjustable with laminatedshims.

The six sensors are housed in a single casing. The electricalconnection is made through two 12 pin connectors.

Operation

The phonic wheel rotates in front of the sensor andproduces a pseudo sinusoidal alternating voltage.

The alternating voltage frequency is proportional to thepower turbine rotation speed and to the number of thephonic wheel teeth.

Phonic wheel Gas generator

F (Hz) =teeth number (d) x rotation speed

60

The X1 and Y3 sensors are connected to the DigitalControl Unit for the control system operation.

The X3 and Y1 sensors are connected to the power turbineoverspeed protection circuit.

The X2 sensor is connected to the speed indicator locatedin the cockpit.

The Y2 sensor is not used.

Note: In a twin-engine configuration, the same indicatorcan display the rotor speed and the two powerturbine speeds.


ARRIUS 1


Training Notes

N2 SPEED SENSORS - DESCRIPTION - OPERATIONSPEED MEASUREMENT AND INDICATING SYSTEM

(F)

N F = N x d60

X2

X1-X3

Y1-Y3

Y3 Y2 Y1

X3 X2 X1

DIGITALCONTROL UNIT

(control system andoverspeed protection)

N2 SPEEDINDICATOR

PRINCIPLE OF SPEED MEASUREMENT

SCHEMATIC DIAGRAM

DESCRIPTION

Magneticcore

PHONICWHEEL (d)

COCKPIT

12 PINCONNECTORS

ELECTROMAGNETICSENSORS

PHONICWHEEL

Gap = 0.5 mm (0.018 inch)Gap



ARRIUS 1

Edition: May 2006

Training Notes

GAS TEMPERATURE MEASUREMENT ANDINDICATING SYSTEM

Function

This system monitors the gas temperature particularlyduring engine starting.

As it is difficult to measure the gas temperature at theturbine inlet, the measurement is carried out at the gasgenerator outlet.

Position

- All the system components are located on the engineexcept the DCU and the t4.5 indicator.


- Type: thermocouple probes

- Indication: degrees Celsius.

Main components

- Thermocouple probes

- t4.5 conformation box

- Digital Control Unit

- t4.5 indicator (aircraft manufacturer's supply).

Description

Refer to following pages.

General operation

The t4.5 gas temperature is an operating parameter,particularly during engine starting.

The signal from the thermocouples is used for:

- Engine control (start fuel flow control)

- Indication (in degrees Celsius).


ARRIUS 1


Training Notes

GAS TEMPERATURE MEASUREMENT AND INDICATING SYSTEM

t4.5 THERMOCOUPLEPROBE LOCATION

CONFORMATIONBOX

DIGITALCONTROL UNIT

t4.5 INDICATOR(cockpit)

FUEL METERINGVALVE



ARRIUS 1

Edition: May 2006

Training Notes


THERMOCOUPLE PROBES - t4.5 CONFORMATIONBOX - GENERAL

Function

The thermocouple probes measure the gas temperature(t4.5) at the gas generator outlet.

Position

- The thermocouple probes are installed on the powerturbine diffuser casing. The tip of the probes is set in thegas flow before the power turbine nozzle guide vanes.

- The t4.5 conformation box is secured by three bolts ona support located above the gas generator.


- Type: Chromel-Alumel

- Quantity: 4 double probes

- Connection: to the conformation box, in parallel.

Main components

- 4 double thermocouple probes

- t4.5 conformation box.


ARRIUS 1


Training Notes

THERMOCOUPLE PROBES AND t4.5 CONFORMATION BOX - GENERALGAS TEMPERATURE MEASUREMENT AND INDICATING SYSTEM

CONFORMATIONBOX

DOUBLETHERMOCOUPLE

PROBES

Thermocouple typeChromel - Alumel

Quantity4 double probes

ConnectionTo the conformation box,

in parallel



ARRIUS 1

Edition: May 2006

Training Notes


THERMOCOUPLE PROBES - t4.5 CONFORMATIONBOX - DESCRIPTION - OPERATION

Description

Each double thermocouple sensor includes:

- A cold junction subjected to the indicator temperature

- A chromel conductor

- An alumel conductor

- A hot junction subjected to the gas temperature.

The conformation box includes:

- Some resistors to produce a uniform gas temperatureindication for a given turbine inlet temperature

- A shorting link support (not used).

Operation

A thermocouple probe produces an electromotive forceproportional to the temperature difference between the hotjunction (gas temperature) and the cold junction (indicatortemperature).

This electromotive force is then provided through theconformation box:

- To the Digital Control Unit for the starting controlsystem

- To the gas temperature indicator (millivoltmeter) locatedin the cockpit.


ARRIUS 1


Training Notes

THERMOCOUPLE PROBES AND t4.5 CONFORMATION BOX - DESCRIPTION - OPERATIONGAS TEMPERATURE MEASUREMENT AND INDICATING SYSTEM

COCKPIT

CONFORMATIONBOX

SHORTING LINKSUPPORT(not used)

THERMOCOUPLES

t°

Chromel wire

Alumel wire

ELECTROMOTIVEFORCE

RECEIVER

COLD JUNCTION(indicator temperature)

HOT JUNCTION(gas temperature)

THERMOCOUPLE PROBE

CONFORMATION BOX

RESISTORS

SHORTING LINKSUPPORT(not used)

THERMOCOUPLECONNECTOR

CONDUCTORCONNECTORS (Cr-Al)

ELECTRICALCONNECTOR(Digital Control

Unit and indicator)

RESISTORS

DIGITALCONTROL UNIT

TEMPERATUREINDICATOR



ARRIUS 1

Edition: May 2006

Training Notes

TORQUE MEASUREMENT ANDINDICATING SYSTEM - GENERAL

Function

The system provides an indication of engine torquemeasured on the intermediate gear of the reduction geartrain.

Position

- The hydraulic torquemeter is located in the doubleintermediate gear of the reduction gear train.

- The torque transmitter is secured on the front face of thereduction gearbox casing.


- Torquemeter• Type: hydraulic

- Transmitter• Type: resistive.

Main components

- Hydraulic torquemeter

- Torque transmitter

- Torque indicator.


ARRIUS 1


Training Notes

GENERALTORQUE MEASUREMENT AND INDICATING SYSTEM

TORQUE LIMITWARNING LIGHT

TORQUEINDICATOR

TORQUETRANSMITTER

INTERMEDIATE GEAR OF THEREDUCTION GEAR TRAIN

COCKPIT

HYDRAULICTORQUEMETER

- Hydraulic torquemeter located in the double intermediate gear of the reduction gear train

- Resistive type torque transmitter

TORQUE MEASUREMENT



ARRIUS 1

Edition: May 2006

Training Notes

TORQUE MEASUREMENT ANDINDICATING SYSTEM -DESCRIPTION - OPERATION

Description

The hydraulic torquemeter includes:

- A restrictor which controls the torquemeter oil inlet(lubricating oil pump pressure)

- A stop

- A piston linked to the intermediate gear through a ballbearing and a securing nut

- An orifice which supplies the torque transmitter withmodulated pressure (pressure which represents thetorque).

The torque transmitter includes:

- A resistive system which measures the modulatedpressure provided by the torquemeter

- An electrical connector which connects the transmitterto the torque indicator in the cockpit.

Operation

In normal operation, the lubricating oil pump supplies therestrictor, which controls the torquemeter inlet pressure.

This inlet pressure acts on the front face of the piston andbalances the axial force F of the intermediate gear whichhas helical teeth (reaction changing with the load).

The piston is fixed on the intermediate gear. Any gear axialmovement determines a new balanced position of thepiston by modifying the oil flow between the modulatedpressure chamber and the piston chamber.

The torque transmitter measures the modulated pressureand delivers an electrical signal to the torque indicatorlocated in the cockpit.


ARRIUS 1


Training Notes

DESCRIPTION - OPERATIONTORQUE MEASUREMENT AND INDICATING SYSTEM

F

TORQUETRANSMITTER

TORQUEINDICATOR

From lubricationpump

Modulated pressure(measured by the

torque transmitter)

Modulated flowaccordingto torque C

PISTON

STOP

OIL INLETRESTRICTOR

TORQUEMETERPISTON

Axial forceon the piston

INTERMEDIATEGEAR



ARRIUS 1

Edition: May 2006

Training Notes

TORQUE MEASUREMENT ANDINDICATING SYSTEM

TORQUE TRANSMITTER

Function

The transmitter transforms a modulated pressure into anelectrical signal.

Position

- In the system: downstream of the filter, after the torquepressure restrictor

- On the engine: on the front face of the reduction gearboxcasing.


- Type: resistive

- Output signal: electrical voltage proportional to thetorquemeter oil pressure

- Output pressure (100% torque): 740 kPa (107.3 PSI)

- Output voltage (100% torque): 370 mV.


The transmitter contains a resistor bridge mounted on adeformable support. The pressure causes the variation ofone of the resistor.

The indicator supplies the reference input voltage (Ve).This voltage is fixed. The bridge provides an outputvoltage (Vs) of a few millivolts proportional to the oilpressure.


ARRIUS 1


Training Notes

TORQUE TRANSMITTERTORQUE MEASUREMENT AND INDICATING SYSTEM

TORQUETRANSMITTER

TypeResistive

Output signalElectrical voltageproportional to the

torquemeter oil pressure

Output pressuretorque 100%

740 kPa (107.3 PSI)

Output voltagetorque 100%

370 mV Ve : Constant input voltage (resistor bridge supply)Vs : Variable output voltage (measurement)

Vs3

2

4

5

1-

-

+

+VeCOCKPIT

(to torque indicator)

Modulatedpressure

TORQUE %

100

740 kPa



ARRIUS 1

Edition: May 2006

Training Notes

MISCELLANEOUS INDICATIONS

INDICATORS

Indicator lights

Some indicator lights provide indications of the engineoperation.

The control panel includes the following indicating lights:

- Chips

- Min. oil pressure

- Fire

- Redundancy or min.or failure (amber GOV)

- Training

- Major failure (red GOV).

The torque indicator includes the max. power warninglight (torque higher than 80%; ∆N1 > "0" twin-engine,rotor load factor).

The speed indicator includes the OEI 2 min. 30 sec.warning light (permanently switched off since power on,except if OEI 30 min. is selected).

Alphanumeric display

The alphanumeric display is connected to the DCU.

It displays some information in real or delayed time (referto the following pages for more details).


ARRIUS 1


Training Notes

INDICATORSMISCELLANEOUS INDICATIONS

0

12

CONTROL PANEL

ALPHANUMERIC DISPLAY

TORQUE INDICATOR ∆N1 INDICATOR

MAX. POWERWARNING LIGHT

(torque, ∆N1,load factor)

OEI 30 min.WARNING LIGHT

FIRE 1 AND 2

GOVERNORMIN. OILPRESSURE

TRAINING

GOVERNORCHIPS 1 AND 2



ARRIUS 1

Edition: May 2006

Training Notes


∆N1 MEASUREMENT AND INDICATING SYSTEM

Function

The ∆N1 indicator displays the margin available in relationto the max. take-off power.

It thus avoids permanent evaluation of the limit whichmust be respected.

Position

- Aircraft cockpit.


- Indicator graduated in percent

- Signal supplied by the DCU.

Main components

- Engine sensors

- Digital Control Unit

- Indicator.

Operation

The DCU supplies the margin value between the actualpower and the max. take-off power. The limit parameter iscontinuously calculated and corresponds to the zero valueof the indicator.

The double indicator is graduated in percent. The marginbetween the indicator needle and the limit value representsthe reserve or the exceeding in relation to the limit value.The display is achieved on an expanded scale (-8 to +4%).

The DCU carries out continuously the followingcomparisons:

- Real N1-limit N1 (T/O N1), that is to say ∆N1.

- Real CH fuel flow-limit CH (T/O CH), that is to say∆CH. The ∆CH is converted to ∆N1.

The DCU compares the two ∆N1 and sends to the indicatorthe nearest ∆N1 from the T/O limit or the one whichexceeds this limit ("0" of the indicator).

Note: During power-up of the DCU, the indicator needlemakes a partial sweep of the graduated scale.


ARRIUS 1


Training Notes

∆N1 MEASUREMENT AND INDICATING SYSTEMMISCELLANEOUS INDICATIONS

0 (T/O)

-8

(OEI 2'30")

(MCP)

∆N1 INDICATOR

(OEI 30')

+4

∆N1 SIGNAL


T/O N1 (fP0, T1)

REAL N1

T/O CH

REAL CH

∆CH TO ∆N1CONVERSION

∆N1SIGNAL

∆N1 ∆CH

∆N1

ENGINE 1 AND 2NEEDLES

DIGITALCONTROL

UNIT



ARRIUS 1

Edition: May 2006

Training Notes


DISPLAY SYSTEM - GENERAL - DESCRIPTION

General

Function

The system displays parameters, operating status andfailures.

Main components

Main components of the system:

- Display unit

- Control module

- Digital Contol Unit

- Engine sensors.

Description

Display unit

It is an alphanumeric display with 5 digits, located in thecockpit.

In a twin-engine configuration, the display units of the twoengines are located one above the other.

Control module

It includes the following components:

- Mode selector• N1 mode• Failure mode• Memory mode• Parameter mode.

- Test selector• Test mode• Scroll mode.

- Trim controls.


RS 232 serial link.

Engine sensors

Refer to the corresponding chapters.


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Training Notes

DISPLAY SYSTEM - GENERAL - DESCRIPTIONMISCELLANEOUS INDICATIONS

Memory

Parameters

Failure

TESTN1

N1 TRIM

NR ADJ

ENGINE 2DCU

ENGINE 1DCU

SCROLL

CONTROLMODULE

ALPHANUMERICDISPLAY

ENGINE 1

ENGINE 2

ENGINE 2SENSORS

ENGINE 1SENSORS

SERIAL DATALINKS



ARRIUS 1

Edition: May 2006

Training Notes


DISPLAY SYSTEM - OPERATION

The display unit has four operating modes: Ng, failure,memory, parameter.

"N1" mode

It is the normal mode in flight.

The four digits, located on the right, display the gasgenerator speed (N1 or Ng) in tenths of one percent.

The digit located on the left displays the letter "S" foroverspeed arming. At power up, the letter "S" mustextinguish at a speed of approx. 25% N2.

"Failure" mode

It displays engine and control system failure codes.

In case of several failures, the failure display is sequential :each failure is displayed for 3 seconds.

"Memory" mode

This mode can be used after flight, engine stopped.

The system sends the failure code that is in the NOVRAMtype memory of the control module.

Note: "Memory" mode is not available in flight (N1>20%)

"Parameter" mode

This mode helps in fault finding.

This mode can be used on ground, engine stopped orrunning and during a test flight.

This mode displays the failure codes, the logic output andinput status, the trim and sensor status in real time.

Note: Refer to the maintenance manual for moreinformation.


ARRIUS 1


Training Notes

DISPLAY SYSTEM - OPERATIONMISCELLANEOUS INDICATIONS

3 - Ng speed (N1)

"N1" MODE "FAILURE" MODE "MEMORY" MODE "PARAMETER" MODE

321

1 - Overspeed armed(switched off above 25% N2)

2 - BUS condition

CARB

T1P0

P COLTRIM

P2T4

ALIMNgNp

OVSPOIL FE BUS

Major failure

Minor failures

Redundancy failures

Overspeednot armedOverspeedOil filterSerial data link

A ……B ……C ……

OIL FDI T1DI P0E BUS

Last flight storedfailures

Failures

D ……E ……F ……

G ……H ……J ……

L ……………M ……………N ……………P ……………

Logic outputs

Logic inputs

α 0%α 1%T1°CP0 mb

MODE TABLE

Refer to themaintenance manual for

more information.

9.1STARTING

ARRIUS 1


Training Notes

9 - STARTING

- Starting system....................................................... 9.2

- Starter ..................................................................... 9.6

- Ignition system (74-00(00) ..................................... 9.10

• Ignition unit (74-10-01)....................................... 9.12

• Igniter plugs (74-20-01) ...................................... 9.14

• Ignition cables (74-20-01) ................................... 9.16 to 9.17


9.2STARTING


ARRIUS 1

Edition: May 2006

Training Notes

STARTING SYSTEM - GENERAL -DESCRIPTION

Function

The starting system ensures starting (on the ground and inflight) and ventilation of the engine. It includes the followingfunctions: cranking, fuel supply, ignition, sequential controland indicating.

Position

All the starting accessories are installed on the engineexcept the Digital Control Unit which is installed in theaircraft.

Indicating and control components, except the DCU, aresupplied by the aircraft manufacturer.


- Starting envelope: refer to flight manual

- Start duration: approx. 30 sec.

- Dry crank time: approx. 20 sec. max.

- Stabilisation time before shut-down: ≥ 60 seconds

- Max. gas temperature during starting: refer to flightmanual.

Description

The system includes the following components:

- In the cockpit:• Fuses• Stop-Training-Flight selector• Dry crank push-button• Rotor brake microswitch

- In the aircraft:• Starter contactor• Accessory relay• DCU

- On the engine:• Starter• Ignition system• Start electro-valve• Stop electro-valve.

9.3STARTING

ARRIUS 1


Training Notes

STARTING SYSTEM - GENERAL - DESCRIPTION

TRAINING

FLIGHT

STOP

ROTOR BRAKEMICROSWITCH

Starting envelope:Refer to Flight Manual

Start duration:Approx. 30 sec.

Dry crank time:Approx. 20 sec. max.

Stabilisation timebefore shut-down:

≥ 60 seconds

Max. gas temperatureduring starting:

Refer to flight manual

COCKPIT COMPONENTS ENGINE COMPONENTS

STARTER

IGNITION SYSTEM

START ELECTRO-VALVE

STOP ELECTRO-VALVE

FUSES

STOP-TRAINING-FLIGHTSELECTOR

DRY CRANKPUSH-BUTTON

28V BUS BAR

0V LOGICBUS BAR

ACCESSORYRELAY

DCU

STARTERCONTACTOR

9.4STARTING


ARRIUS 1

Edition: May 2006

Training Notes

STARTING SYSTEM - OPERATION

This section deals with operating sequences associatedwith the starting system: starting, shut-down and drycrank.

Starting cycle

The starting cycle is characterised by the evolution of theengine parameters and particularly the rotation speed andgas temperature.

The main points of the starting cycle are:

- Start selection

- Self-sustaining speed (the starter and ignition systemare turned off)

- End of starting (stabilisation at idle speed).

Shut-down cycle

The typical phases of this cycle are the following:

- Stabilisation at idle speed

- Stop selection

- Run-down until the complete engine stop.

Dry crank cycle

A dry crank consists of cranking the rotating assemblywithout supplying fuel or ignition (dry ventilation). It isused for cooling the engine or for maintenance procedures.

The dry crank cycle comprises the following phases:

- Dry crank selection

- Cranking of the rotating assembly

- End of dry crank and run-down.

9.5STARTING

ARRIUS 1


Training Notes

STARTING SYSTEM - OPERATION

N2 100%

DCU

ACCESSORYRELAY

STARTERCONTACTOR

Startingaccessories

Starter

START

SELECTION

DRY CRANK SELECTION

+

+

Time

N1

TimeN1

FlightN2 92%Training

Self-sustainingspeed

Selection

t4.5 gastemperature

Stop selection

Run-down

SHUT-DOWN CYCLE

N1 Dry crank cancel

STARTING CYCLE DRY CRANK CYCLESelection

Stabilisationat idle speed

Time(20 sec. max.)

9.6STARTING


ARRIUS 1

Edition: May 2006

Training Notes

STARTER - GENERAL

Function

The starter drives the gas generator rotating assemblywithin given conditions of torque and acceleration.

At the end of starting and when the rotation speed issufficient, the starter operates as a generator.

Position

The starter is located on the front face of the gearboxcasing.



- Type: starter generator

- Power supply: direct current on high intensity line.

Main components

The main components of the starter are:

- The starter (starter and generator)

- The mounting flange

- The supply terminals.

Interfaces

- Electrical supply of the starter from the batteries throughthe starter contactor

- Direct current supply to the aircraft circuit from thegenerator when the starting phase is completed

- Drive of the gas generator rotating assembly through theaccessory drive train.

9.7STARTING

ARRIUS 1


Training Notes

STARTER - GENERAL

STARTERCONTACTOR

SUPPLYBUS BAR

+VDC

STARTER

ELECTRICAL INTERFACE

Directcurrent

Aircraftelectrical system

MECHANICAL INTERFACE

STARTER ACCESSORYDRIVE TRAIN

DRIVE OF THEGAS GENERATOR

ROTATING ASSEMBLY

Aircraft manufacturer'ssupply

TypeStarter generator

Power supplyDirect current

on high intensity line

9.8STARTING


ARRIUS 1

Edition: May 2006

Training Notes

STARTER - DESCRIPTION - OPERATION

The starter includes the following components:

- Supply terminals• Excitation• Generator• Negative terminal (-)• Starter• Balancing.

- Casing (starter frame)

- Mounting flange on gearbox casing

- Brushes

- Windings (stator and rotor)

- Fan

- Splined shaft

- Commutator.

Operation

The starter ensures:

- The engine cranking during starting

- The electrical supply to the aircraft electrical system atthe end of the starting phase.

Engine cranking

When the start is selected (in the cockpit), the startercontactor closes and allows the direct current supply of thestarter through the aircraft supply bus bar.

The electrical motor of the starter then provides the torquerequired to crank the gas generator.

The cranking torque is inversely proportional to the gasgenerator rotation speed. The torque increases when theatmospheric temperature decreases.

The gas generator rotation speed increases up to a selfsustaining speed (50% N1). At a speed of 50%, the torquebecomes negative and the electrical supply to the startermotor is cut (opening of the starter contactor).

Electrical generator

When starting is completed (N1 > 50%), the electricalsupply to the starter motor is cut, but the starter ismechanically driven by the gas generator through theaccessory drive train. The starter then operates as anelectrical DC generator and supplies the aircraft electricalsystem.

9.9STARTING

ARRIUS 1


Training Notes

STARTER - DESCRIPTION - OPERATION

WINDINGS(stator and rotor)

CASINGMOUNTING FLANGE(on reduction gearbox

casing)

BRUSHES

SPLINED SHAFT

COOLING FAN

SUPPLY TERMINALS

COMMUTATOR

Balancing (Eq)

COOLING AIR

Generator (+G) Starter (+D)NegativeterminalExcitation (Ex)

STARTINGTORQUE

SELF-SUSTAINING SPEED

DECREASING ATMOSPHERICTEMPERATURE

GENERATORSTARTER

ELECTRICAL CURRENT GENERATION

AIRCRAFT SYSTEMELECTRICAL SUPPLY

+D

-

+G

Eq

Ex

+

+ VDC

50% N1

0

9.10STARTING


ARRIUS 1

Edition: May 2006

Training Notes

IGNITION SYSTEM

Function

This system ensures the ignition of the fuel sprayed by thestart injectors into the combustion chamber.

Position

- All the ignition system components are installed on theengine except the electrical supply circuit.


- Type: High Energy (HE)

- Electrical power supply: 10 to 32 VDC.

Main components

- Ignition unit

- Ignition cables

- Igniter plugs.

Note: Refer to the following pages for the descriptionand the operation of the ignition systemcomponents.

9.11STARTING

ARRIUS 1


Training Notes

IGNITION SYSTEM

TypeHigh Energy (HE)

Electrical power supply10 to 32 VDC

M

PP21 bus

PP8 bus

High Energyignition unit

Igniterplugs

Ignitioncables

Startercontactor

M controlrelay

Starter

9.12STARTING


ARRIUS 1

Edition: May 2006

Training Notes

IGNITION SYSTEM

IGNITION UNIT

Function

The ignition unit transforms the DC voltage provided bythe aircraft circuit into high energy voltage required tooperate the igniter plugs.

Position

The unit is installed on the upper right part of the air intakeplenum (aircraft).

Main characteristics- Type: High Energy, sealed case.

Main components

The main components of the ignition unit are:

- The High Energy ignition unit

- The DC electrical connector

- The HE electrical connectors

- The cables which connect the ignition unit to the igniterplugs.

Operation

The ignition unit operation is characterised by anaccumulation phase of the electrical loads and a quickdischarge phase.

The ignition unit is supplied with 28 V, it changes this toa high energy voltage (3 kVolts).

9.13STARTING

ARRIUS 1


Training Notes

IGNITION UNITIGNITION SYSTEM

TypeHigh Energy, sealed case

INPUT ELECTRICALCONNECTOR(direct current)

HIGH ENERGYIGNITION UNIT

OUTPUT ELECTRICALCONNECTORS

(High Energy current)

CABLES(to igniter plugs)

9.14STARTING


ARRIUS 1

Edition: May 2006

Training Notes

IGNITION SYSTEM

IGNITER PLUGS

Function

The two igniter plugs ignite the fuel/air mixture sprayed bythe start injectors during starting. Two cables connect theigniter plugs to the ignition unit.

Position

- The igniter plugs are installed beside two start injectors.They are located at the rear of the combustion chamberon each side of the engine (at 11 o'clock and 5 o'clock).


- Type: High Energy, surface discharge (semi-conductorsurface coating)

- Quantity: 2.

Description

An igniter plug includes:

- An external body connected to the negative terminal

- An insulator

- A central electrode connected to the positive terminal

- A semi-conductor.

Operation

When the high energy current produced by the ignitionunit is discharged to the igniter plug, the voltage appliedbetween the central electrode and the external bodyproduces a powerful spark.

This spark ignites the fuel/air mixture sprayed into thecombustion chamber by the two start injectors.

9.15STARTING

ARRIUS 1


Training Notes

IGNITER PLUGSIGNITION SYSTEM

IGNITERPLUG Engine rear face

IGNITERPLUG

Spark

EXTERNALBODY

(-)

CENTRALELECTRODE

(+)

SEMI-CONDUCTOR

INSULATOR

SLEEVE

MOUNTINGFLANGE

SEALS

ELECTRICALCONNECTOR

(to ignition unit)

TypeHigh Energy

Semi-conductor

Quantity2

9.16STARTING


ARRIUS 1

Edition: May 2006

Training Notes

IGNITION SYSTEM

IGNITION CABLES

Function

The ignition cables supply the high energy current(produced by the ignition unit) to the igniter plugs.

Position

- Between the ignition unit and the igniter plugs.


- Type: multi-core nickel-plated copper wire

- Quantity: 2 identical independent cables

- Shielding: triple braided.

Description

One ignition cable includes:

- A nickel-plated copper multicore

- An outer shielding (stainless steel braid)

- Two inner shields (silver-plated copper braid)

- Two stainless steel rigid end fittings

- Two electrical connectors• One igniter plug connector (ceramic insulator, spring

and nut)• One ignition unit connector (teflon insulator, silicone

joint, spring and nut).

9.17STARTING

ARRIUS 1


Training Notes

IGNITION CABLESIGNITION SYSTEM

TypeMulti-core nickel-plated

copper wire

Quantity2 identical and

independent cables

ShieldingTriple braided

ELECTRICAL CONNECTOR(connection with the ignition unit)

ELECTRICAL CONNECTOR(connection with the igniter plug)

IGNITION CABLE(wire and shield)

10.1ELECTRICAL SYSTEM

ARRIUS 1


Training Notes

10 - ELECTRICAL SYSTEM

- Electrical system ................................................ 10.2

- Alternator ........................................................... 10.4

- Electrical harnesses (77-30-02) .......................... 10.6 to 10.7




ARRIUS 1

Edition: May 2006

Training Notes

ELECTRICAL SYSTEM

Function

The system contributes to the various indicating and controlfunctions of the engine:

- Control

- Control system

- Safety system

- Maintenance aid.


- Direct current: 28 VDC from aircraft electrical system

- Dedicated alternator electrical power: 100 VA.

Main components

- Engine electrical components (control components andsensors)

- Control and indicating components

- Digital Control Unit (installed in the airframe)

- Electrical harnesses.


ARRIUS 1


Training Notes

ELECTRICAL SYSTEM

CONTROLAND INDICATINGCOMPONENTS

DIGITALCONTROL UNIT

ACCESSORIESAND SENSORS

ELECTRICALHARNESSES

Direct current:28 VDC from aircraft

electrical system

Dedicated alternatorelectrical power:

100 VA



ARRIUS 1

Edition: May 2006

Training Notes

ALTERNATOR

Function

The altenator is dedicated to the Digital Control Unitelectrical supply.

Position

- On the engine: on the front face of the reduction gearbox.


- Type: Three-phase, continuous operation

- Power: 100 VA

- Output voltage: 28 to 63 Volts.

Main components

- Drive shaft

- Body

- Rotor

- Electrical connector (to the DCU).

Note: The rotor is mounted on the drive shaft.

The LP fuel pump and the alternator are driven bythe same shaft.

Operation

The three-phase voltage produced by the alternator is sentto the Digital Control Unit

An electrical connector connects the alternator to theDigital Control Unit and is protected by a fuse.

DCU power supply

The DCU is electrically supplied either from the 28 Vaircraft supply (J2 connector) or from the engine alternator(J1 connector) as follows.

- The 28 V aircraft supply is used alone:• During starting• In case of an alternator failure during flight.

- The alternator is used during flight (normal operation)

- The alternator is used alone in case of 28 V aircraftsupply failure during flight.


ARRIUS 1


Training Notes

ALTERNATOR

U

+

STATOR

DIGITAL CONTROL UNITSUPPLY PRINCIPLE

Normal operation

28V network aircraft failure

Alternator failure

Aircraft supply

Aircraft supply

Alternator

Alternator

Aircraft supply

N1

0% 100%50%

LP PUMP

ELECTRICAL CONNECTOR(to DCU)

ALTERNATOR

FUSE(in the alternator

connector)

INSIDETHE DCU

TypeThree-phase,

continuous operation

Power100 VA

Output voltage28 to 63 Volts



ARRIUS 1

Edition: May 2006

Training Notes

ELECTRICAL HARNESSES

Function

The harnesses connect the electrical accessories to theDCU and the aircraft circuit.


- Cable type: plaited, shielded or overshielded

- Connector type: screw-in connectors.

Main components

The main electrical harnesses connect:

- The engine to the aircraft controls, indicators andindicating lights

- The engine accessories and sensors to the DCU J1 plug

- The engine accessories and sensors to the DCU J5 plug

- The battery to the DCU

- The DCU to the aircraft indicating lights

- The 1st engine DCU to the 2nd engine DCU (twin-engine configuration).


The engine electrical harness connects the engine to theaircraft systems.

Two electrical plugs connect the engine accessories to theDCU J1 and J5 plugs through the P1 and P5 connectors.

The third plug connects the engine to the aircraft controls,indicators and indicating lights.


ARRIUS 1


Training Notes

ELECTRICAL HARNESSES

AIRCRAFT/ENGINECONNECTION

P5 CONNECTOR P1 CONNECTORAIR TEMPERATUREPROBE

DCU / ENGINECONNECTION

11.1ENGINE INSTALLATION

ARRIUS 1


Training Notes

11 - ENGINE INSTALLATION

- Engine compartment .......................................... 11.2

- Engine mounting and lifting (71-20-01) ............ 11.4

- Power drive .......................................................... 11.6

- Air intake ............................................................. 11.8

- Exhaust system (78-10-01).................................. 11.10

- Drain system ........................................................ 11.12

- Fire protection (26-10-01)................................... 11.14 to 11.15




ARRIUS 1

Edition: May 2006

Training Notes

ENGINE COMPARTMENT

Function

The helicopter engine compartment houses the enginesand ensures their ventilation.

Position

- At the rear of the helicopter main gearbox.

Description

Each engine compartment includes:

- Three fire walls which ensure sealing and protection incase of fire:

• One firewall is located in front of the engine (betweenthe helicopter main gearbox and the engine)

• One firewall is located at the rear of the engine• One firewall separates the two engine compartments.

- A removable cowling, located above the enginecompartment, which mainly includes:

• The engine air intake• An oil cooler air outlet• Compartment ventilation scoops…

- Removable cowlings which allow access to the engines

- A support platform fitted with engine support fittings.

Engine compartment ventilation

The engine compartment is ventilated by atmospheric airin order to limit the temperature in different engine areas.

The atmospheric air circulation through the compartmentis ensured by ventilation scoops located on each side of theremovable cowling. The air is accelerated by the venturiextension of the exhaust system.


ARRIUS 1


Training Notes

ENGINE COMPARTMENT

FRONTFIREWALL

SUPPORT PLATFORM(fitted with the engine

support fittings)

REARFIREWALL

ENGINECOMPARTMENTS

ENGINE

ENGINE

FIREWALL (separation of the

engine compartments)

REMOVABLECOWLING

REMOVABLE COWLING- Engine air intake- Oil cooler air outlet- Compartment ventilation scoops



ARRIUS 1

Edition: May 2006

Training Notes

ENGINE MOUNTING AND LIFTING

Engine mounting

Function

The engine mountings attach the engine to the airframe.

Description

- Front support: circular flange fitted with nine studs

- Rear support: bracket fitted on the underside of thegearbox casing.

Engine lifting

Function

The lifting rings permit engine lifting.

Description

- At the front: one ring fitted on the gearbox casing flange

- At the rear: two rings fitted on the compressor casingflange.

Engine removal and installation

Turbomeca provides an engine lifting sling which attachesto the lifting rings on the engine.

This permits the removal and installation of the engine inthe airframe.

The removal/installation procedure is described in theairframe maintenance manual and must only be carried outin accordance with this procedure, using the appropriatetool.


ARRIUS 1


Training Notes

ENGINE MOUNTING AND LIFTING

LIFTINGSLING

REAR LIFTINGRINGS

FRONT LIFTINGRING

REARATTACHMENT

ENGINESTAND

ENGINE SUPPORTBRACKETS

(on engine stand)

REARATTACHMENT

FRONTATTACHMENT

TRANSPORTATTACHMENT



ARRIUS 1

Edition: May 2006

Training Notes

POWER DRIVE

Function

The engine power drive provides the mechanical powerrequired to drive the helicopter main gearbox.

Position

- The power drive is located at the front lower part of thegearbox casing.


- Mechanical power: 350 kW (470 HP)

- Rotation speed: 6016 RPM (100% N2); CW.

Description

The power drive includes a triangular flange which issplined onto the output gear and secured by a nut. Thetriangular flange has three bolt holes.

Power drive sealing is ensured by a graphite seal installedaround a ring which is fitted on the output shaft.

The power drive casing also has a drain which expels anyoil leaks.

Helicopter main gearbox - engine transmission

The link to the helicopter main gearbox is ensured by:

- A flexible coupling installed on the triangular flange

- A transmission shaft

- A helicopter coupling which links the transmission shaftto the helicopter main gearbox.

Note: The transmission system is supplied by the aircraftmanufacturer.


ARRIUS 1


Training Notes

POWER DRIVE

GRAPHITESEAL

RING

ROLLERBEARING

POWER DRIVE(triangular flange)

REDUCTION GEAROUTPUT SHAFT

TRANSMISSIONSHAFT

HELICOPTERMAIN GEARBOX

HELICOPTERCOUPLING

POWERDRIVE

(triangular flange)

SECURINGNUT

DRAIN

FLEXIBLECOUPLING

REDUCTION GEAROUTPUT GEAR



ARRIUS 1

Edition: May 2006

Training Notes

AIR INTAKE

Function

The air intake system collects and guides the ambient airinto the engine.

Position

- On each side of the helicopter, at the rear of the maingearbox.


- Lateral air intake on aircraft and annular air supply for

each engine (plenum chamber).


The air intake system includes the following components :

- Air intake duct. Supplied by the aircraft manufacturer, itcomprises filtering and protecting elements

- Air intake plenum. Supplied by the aircraft manufacturer,it ensures a good air supply to the engine

- Air intake volute and engine air intake casing (refer tochapter "ENGINE"). A compressor cleaning connectioncan be installed on the intake and a vibration sensorsupport is installed permanently.


ARRIUS 1


Training Notes

AIR INTAKE

AIR INTAKEDUCT

AIR INTAKEPLENUM

AIR INTAKEGUARD

ENGINE AIRINTAKE CASING



ARRIUS 1

Edition: May 2006

Training Notes

EXHAUST SYSTEM

Function

The exhaust system discharges the exhaust gas overboard.

Position

- At the rear of the engine.


- Type: axial, exhaust pipe with extension

- Replaceable non modular component.

Main components

- Engine exhaust pipe

- Exhaust extension.


The gases pass from the engine exhaust to the extensionwhich directs the gases overboard through the cowlingpassage.

Air is drawn from the engine compartment by the venturieffect between the extension and the exhaust pipe thusensuring compartment ventilation.

The oil system vent pipe is connected to a mounting on topof the exhaust pipe.


ARRIUS 1


Training Notes

EXHAUST SYSTEM

Oil systemvent line

POWERTURBINE

EXHAUSTPIPE

EXTENSION

GAS EXHAUST

Engine compartment air suctionby venturi effect



ARRIUS 1

Edition: May 2006

Training Notes

DRAIN SYSTEM

Function

The drain system collects the various drains and any leaksfrom the engine.

Engine drains

LP fuel pump drive drain

It is a dry drain which will collect any leaks between thetwo seals of the alternator/LP pump drive shaft

HP fuel pump unit drain

It is a dry drain which will collect:

- Any fuel which leaks between the two seals installed onthe HP pump drive shaft

- Any fuel which leaks from the fuel metering unit.

Combustion chamber drain

The combustion drain valve drains the residual fuel duringengine shut-down and during starting.

Power drive drain

This drain will collect any leaks from the power drive.There are in fact two orifices, one on each side of thesupport.

Fuel valve assembly support drain

The fuel valve assembly is mounted on a dished steel platewhich is equipped with a drain pipe at each side at the rear.Any fuel leaks from the fuel valve will be dischargedoverboard via these drain pipes.


ARRIUS 1


Training Notes

DRAIN SYSTEM

HP FUEL PUMP UNITAND METERING UNIT DRAIN

COMBUSTIONCHAMBER DRAIN

POWER DRIVEDRAIN

FUEL VALVEASSEMBLY DRAIN

LP FUEL PUMPDRIVE DRAIN



ARRIUS 1

Edition: May 2006

Training Notes

FIRE PROTECTION

Fire detection

Function

The fire detection system detects overtemperature in theengine compartment and gives a cockpit indication.

Position

- In the system: connected to the cockpit

- On the engine:• "Cold" zone: one detector located on the upper part

of the gearbox mounting flange and one detectorlocated on the LP fuel pump/alternator assembly,

• "Hot" zone: one detector located on the lower part ofthe rear bearing casing and one detector locatedabove the oil inlet union of the rear bearing.


- "Cold" zone:• Detector setting: nominal value: 200°C (392°F),• Quantity: 2

- "Hot" zone:• Detector setting: nominal value: 400°C (752°F),• Quantity: 2

Description

The system includes:

- On the engine: detectors and electrical wiring

- In the aircraft: indicating lights, fire detection unit, testselector and extinguishing system (aircraftmanufacturer's supply).

Fire detectors

Each fire detector includes a bi-metallic strip which opensthe electrical circuit in case of overheat. It is fitted with aresistance in parallel which enables the system todifferentiate between the normal opening of a detector anda wiring defect.

Extinguishing systemThe fire extinguishing system includes an extinguisherbottle and spraying jets. The extinguishing system can beoperated from the cockpit (system supplied by the aircraftmanufacturer).

Note: Refer to the aircraft manual for more informationon the extinguishing system.


ARRIUS 1


Training Notes

FIRE PROTECTION

+

+

+

FIREDETECTOR

"COLD" ZONE

Detector setting:Nominal value:200°C (392°F)

Quantity:2

"HOT" ZONE:

Detector setting:Nominal value:400°C (752°F)

Quantity:2

Note: Refer to the aircraft manual for more information on the extinguishing system.

Detection

logic

Extinguishingbutton

Test button

Alarm

Aircraft Engine

Cold zone Hot zone

INSULATEDBI-METALLIC STRIP

UNINSULATEDBI-METALLIC STRIP

MOUNTINGFLANGE

MECHANICALSTOP

12.1OPERATING LIMITATIONS AND PROCEDURES

ARRIUS 1


Training Notes

12 - OPERATING LIMITATIONS AND PROCEDURES

- Operating limitations ......................................... 12.2

- Operating procedures ........................................ 12.4 to 12.7



ARRIUS 1

Edition: May 2006

Training Notes

OPERATING LIMITATIONS

All operating limitations are defined in the officialdocuments:

- Flight manual

- Maintenance manual(s).

The main engine limitations are:

- Flight envelope

- Gas generator rotation speed

- Power turbine rotation speed

- Turbine entry gas temperature

- Torque

- Miscellaneous (load factors, vibration ...).

The systems general limitations are:

- Pressure, flow, volume, voltage, ...


ARRIUS 1


Training Notes

OPERATING LIMITATIONS

MAINTENANCE MANUAL

FLIGHT MANUAL

ENGINE AND SYSTEMLIMITATIONS

- Flight envelope- Gas generator rotation speed- Power turbine rotation speed- Turbine entry gas temperature- Torque- Miscellaneous (load factors, vibration...)- Pressure, flow, volume, voltage...



ARRIUS 1

Edition: May 2006

Training Notes

OPERATING PROCEDURES (1)

The operating procedures are considered for trainingpurposes only. It is mandatory to refer to the aircraftmanual.

Preparation before starting

- Inspection, checks…

Starting

Start procedures:

- Electrical system power on

- Booster pump on

- Actuate the STOP-TRAINING-FLIGHT selector switch(direct selection of the FLIGHT position is possible)

- Set the selector switch to the FLIGHT position toaccelerate the engine

- Check the indicating lights, the engine parameters:• N1• N2 and NR• Gas temperature• Oil pressure and temperature• The idle control operation• The acceleration and the control system operation at

the normal NR.

Note: To start a cold engine with a low ambienttemperature, the oil temperature must increasebefore any load is applied.

In flight engine control

- Normal automatic procedure: before the engine power-up, check the oil temperature

- The control unit adapts the engine to the flight conditions(control): check the indicating lights and monitor theengine parameters (N1, N2, gas temperature, torque, oilpressure and temperature)

- "Trim" action if necessary: check the effect on NR (rotorspeed) or engine matching.

Engine shut-down

- Stabilisation: minimum collective pitch (stabilisation of60 seconds at least)

- FLIGHT-TRAINING-STOP selector on STOP position:check the parameters and the rundown time.


ARRIUS 1


Training Notes

NORMAL PROCEDURES


STARTING

PRE-START CHECKS

- Inspections, checks…

ENGINE SHUT-DOWN

The operating procedures are considered

for training purposes only. It is mandatory to refer to the

aircraft manual.- Electrical system power on- Booster pump on- Selector actuation (direct selection of the "Flight" position possible)- Checks

- Minimum collective pitch- Stabilisation (approx. 60 sec.)- Selector on "Stop" position- Check…

IN FLIGHT ENGINE CONTROL

- Normal automatic procedure- Engine adaptation to the flight conditions (control system)- "Trim" action if necessary



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Training Notes

Manual control in flight

- Manual control of the metering valve (after a failure orcontrolled "freezing")

- Move the lever in the + or - range to alter the fuel flow

- Check the engine parameters.

Caution

Do not move the lever down below the reductionnotch in order to prevent flame out.

Special procedures (flame out, fire, failures…)

Refer to flight manual.

Note: The operating procedures are considered fortraining purposes only. It is mandatory to refer tothe aircraft manual.


Particular procedures.

Relight

The relight procedure is the same as the ground startprocedure. However, the N1 rotation speed must be lowerthan 17% (automatic interlock).

Engine ventilation

- FLIGHT-TRAINING-STOP selector on STOP position

- Depress the Dry crank push-button

- Check the N1 speed.

Note: No more than 20 seconds.

Training procedures

- Automatic training operating procedure: only with areduced load helicopter; the operating engine limitationsare derated and the other engine is set to the idle rating(N2)

- Manual mode: the main metering valve is "frozen".Allows training for a major failure or manual control.Return to automatic is possible without restriction.


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Training Notes

PARTICULAR PROCEDURES


TRAINING PROCEDURES

- Automatic training operating procedure - Manual mode: allows training for a major failure

DRY CRANK

The operating procedures are considered

for training purposes only. It is mandatory to refer to the

aircraft manual.

MANUAL CONTROL IN FLIGHT

- Metering valve manual control- Move the lever in the + or - range- Check the engine parameters

- Selector on "Stop" position- Dry crank push-button actuated- Check the N1 speed

Note: 20 sec. max.

RELIGHT

- Same procedure as for the ground start procedure- Wait for N1 < 17%

13.1VARIOUS ASPECTS OF MAINTENANCE

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13 - VARIOUS ASPECTS OFMAINTENANCE

- Maintenance concept .................................................... 13.2

- Life limitation ................................................................ 13.4

- Preventive maintenance ................................................ 13.6

- "On-condition" monitoring .......................................... 13.8

- Corrective maintenance ................................................ 13.10

- Technical publications .................................................. 13.12 to 13.15



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Training Notes

MAINTENANCE CONCEPT

Introduction

The engine is designed to have a high availability rate withreduced maintenance.

The main aspects of the maintenance concept are thefollowing:

- Effective modularity

- Good accessibility

- Reduced removal and installation times

- On-condition facility

- Quick repair.

Maintenance levels

Four maintenance levels can be considered:

First line maintenance: engine installed on the aircraft(O level).

- Scheduled and preventive maintenance:• Checks and inspections• Life limit or completed TBO removal

- Corrective maintenance:• Fault detection• Component replacement (LRU)• Check

Second line maintenance: engine maintenance in shop(I level).

- Corrective maintenance: SRU and module removal andinstallation.

Third line maintenance: deep maintenance whichinvolves module repairs (H level).

- Corrective maintenance: component replacement.

Fourth line maintenance: overhaul and repair in specificshop (D level).

- Maintenance scheduled when the TBO is completed orwhen the life limit of a component is reached

- Corrective maintenance.

Other aspects of maintenance

Refer to the following pages.

Note 1: LRU - Line Replaceable Unit

SRU - Shop Replaceable Unit.

Note 2: The maintenance steps are determined by theoperator taking into account the difficulties, thepersonnel and logistic considerations.

As far as the engine manufacturer is concerned,the current maintenance procedures (1st, 2nd

line) are defined and described in themaintenance manual. Deep maintenance (3rd

line) and general overhaul (4th line) aredescribed in other documents and are subject toparticular license agreements.


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Training Notes

MAINTENANCE CONCEPT

2nd LINE MAINTENANCE(I level)

(engine removed)- Corrective maintenance

(modules, SRU)

Maintenance Manual Maintenance TechnicalInstruction

Overhaul Manual

MAINTENANCE LEVELS

3rd LINE MAINTENANCE(H level)

(engine removed)- Deep maintenance

1st LINE MAINTENANCE(O level)

(engine installed on aircraft)- Scheduled or preventive

maintenance- Corrective maintenance

4th LINE MAINTENANCE(D level)

(engine removed in specific shop)- Scheduled maintenance

(overhaul, repair)- Corrective maintenance



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Training Notes

LIFE LIMITATION

TBOsTBOs (Time Between Overhauls) are defined for theengine, the modules and some accessories. These TBOs,determined by tests and experience, are subject to anextension programme.

The TBO is expressed in operating hours.

Life-limited partsCertain components (mainly rotating parts such ascompressor, turbines, …) have a life limit which requiresthe part to be scrapped when the limit is reached. This limitis calculated in hours and/or cycles.

A cycle is a clearly defined operating sequence.

The first limit achieved necessitates their replacement bya deep maintenance procedure or by a TURBOMECAagreed repair centre.

A list of these parts is given in Chapter 5 of the EngineMaintenance Manual, and in Section D of the engine logbook.

Counting of hours and cyclesCycle counting is effected either manually or automatically.The method of counting cycles and the various limits aredescribed in Chapter 5 of the maintenance manual.

A counting check (comparison between automatic countingand manual counting) is a procedure planned in the periodicmaintenance.

A simple check can be carried out by comparing the twoengine readings for a given period of operation.

Calendar limitsThe calendar limit is the time (expressed in years) afterwhich the complete engine, modules or parts subjected tocalendar limit has to be returned to the factory or anapproved repair center.

The count starts at the engine first installation in theaircraft (since new, overhaul or repair).

"On-condition"Some components have no TBO, no life limit, no calendarlimits. They are generally considered as "on-condition".

Use-limited partsThese parts have a maximum usage defined in hours; thisincludes parts such as bearings, casings and shafts. Theirlimits are greater than the normal TBO of the engine, thuspermitting them to be used for two or more TBOs, whichreduce engine overhaul costs for the customer.

These parts and their corresponding limits are listed insection D of the engine log book.


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Training Notes

LIFE LIMITATION

- Manual counting- Automatic counting- Counting check

CALENDAR LIMITS

Time limits (since new, overhaulor repair):- Engine- Modules- Parts

First limit reached:- Operating hours and/or- Operating cycles

Cycles for:- Compressors- Turbines- ...

COUNTING OF HOURSAND CYCLES

Some components have no TBO,no life limit, no calendar limits.They are generallyconsidered as "on-condition".

"ON-CONDITION"

Maximum usage:- Defined in hours- Greater than the normal TBOUsable for two or more TBOs,which reduce engine overhaulcosts

USE-LIMITED PARTS

AUTOMATIC COUNTING

Display inthe cockpitElectronic Control

Unit

TBOs

- Engine- Modules- Accessories

LIFE-LIMITED PARTS



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Training Notes

PREVENTIVE MAINTENANCE

Preventive maintenance includes the procedures whichmust be systematically carried out and the procedureswhich are recommended.

Refer to maintenance manual (chapter 05).

Servicing inspections- Inspection before the "first flight of the day"- Inspection after the "last flight of the day"- Inspection... (according to engine type).

Periodic inspections- These procedures can be "blocked" (at fixed intervals

for all the procedures) or "staggered" (the procedures aredistributed over a period of time to reduce the turnaroundtime while still respecting the intervals)

- Visits are scheduled as a function of flight hours (ex:every 500 hours) or calendar (ex: 2 years)

- Special inspections:• Particular inspections• Inspections according to airworthiness.

The procedures are also qualified as follows:

- Mandatory maintenance tasks.These are actions that must be performed in order tocomply with airworthiness objectives. They are listed,along with their associated frequencies, in the table ofmandatory maintenance tasks.These mandatory maintenance tasks and/or theirassociated frequencies can only be modified with theprior approval of the EASA (European Aviation SafetyAgency) and TURBOMECA.

- Obligatory maintenance tasks.TURBOMECA considers that obligatory maintenancetasks must be performed at the frequencies specified.These obligatory maintenance tasks and/or theirassociated frequencies can be adapted with the priorapproval of TURBOMECA and the RegulatoryAuthorities.

- Optional maintenance tasks.Turbomeca advises that optional maintenance tasks beperformed at the frequencies specified in order to improvereliability and operational availability, and in order toreduce engine operating costs.These optional maintenance tasks and/or their associatedfrequencies can be adapted with the prior approval ofTURBOMECA, subject to compliance with theregulations of the local Regulatory Authorities.

Mandatory maintenance tasks are listed in the"Airworthiness Limitations" section of the MaintenanceManuals. Obligatory and optional maintenance tasks arelisted outside the "Airworthiness Limitations" section.

Main inspection points (preventive maintenance)- Visual inspections- Run-down time check- Magnetic plug and filter inspection- Oil sampling for analysis- Oil level checks- Compressor cleaning (according to operating conditions)- Operating checks and ground run test- Electronic control unit data operation.


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Training Notes

PREVENTIVE MAINTENANCE

MAIN INSPECTION POINTS

- Visual checks - Run-down time check- Inspection of filters - Inspection of magnetic plugs- Oil sampling (for analysis)- Oil level (and replenishment if required)- Compressor cleaning (depending on operating conditions)- Ground run test- Electronic control unit data operation

REFER TO THEMAINTENANCE MANUAL

Chapter 05

PERIODIC INSPECTIONS

- Procedures "blocked" or "staggered" (flight hours or calendar schedule)- Special inspections

SERVICING INSPECTIONS

- Inspection "before the first flight of the day"- Inspection "after the last flight of the day"- Inspection... (according to engine type)

- Mandatory- Obligatory- Optional



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Training Notes

"ON-CONDITION" MONITORING

When applying on-condition maintenance, the maintenanceprocedures are carried out according to the condition ofengine components. It requires a monitoring which includesappropriate procedures studied during the engine design.

Objectives of on-condition monitoring

The objective is to increase safety and to reducemaintenance costs.

This is obtained as the monitoring ensures an early diagnosisof anomalies which could have serious consequences; onthe other hand, monitoring avoids unnecessary maintenancetasks.

On-condition monitoring resources

On-condition monitoring implies an appropriate design ofthe engine which allows the use of monitoring tools.

The following procedures are available:

- Borescopic inspection: this permits inspection of internalparts which are not accessible without disassembly:compressor, combustion chamber and turbine. A specialtool is used to allow direct visual inspection of the parts

- Lubrication oil check: various methods are used to checkfor the contamination of the oil (magnetic plugs, strainerssampling). Samples of oil are taken at regular intervalsand the samples are analysed to measure thecontamination and anticipate incipient failures (analysisby magnetoscopy, ferrography, spectrometric oilanalysis)

- Vibration level check: the vibration level of the rotatingassemblies gives an indication of the engine condition.Sensors installed at given points are used to measure thevibration level. This type of check is carried out duringperiodic inspections or according to engine condition

- Power check: the monitoring is ensured by means of theElectronic Control Unit (refer to "CONTROL SYSTEM"chapter and Flight Manual)

- Visual inspection: conventional visual inspections arealso considered for on-condition monitoring (air intakeinspection, exhaust pipe inspection, exhaust and engineexternal inspections…).


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Training Notes

"ON-CONDITION" MONITORING

- To increase safety- To reduce maintenance costs

OBJECTIVES OFON-CONDITION MONITORING

POWER CHECK

BORESCOPIC INSPECTION VIBRATION CHECK VISUAL INSPECTION

LUBRICATION OIL CHECK



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Training Notes

CORRECTIVE MAINTENANCE

Objective of corrective maintenance

The objective is to put the engine back into normal serviceas soon as possible. Corrective maintenance includes allprocedures which must be carried out when required(failure, fault…). It implies general and particular activities.

Corrective maintenance main tasks

- Fault finding (refer to Maintenance Manual or TroubleShooting Manual: chapter 71)

- Functional checks

- Condition checks

- Removal and installation: removal and installation ofthe complete power plant, of the accessories and of themodules and of some engine components as required.

Note: Assembly and disassembly of the engine is dealtwith in general overhaul and repair.

- Adjustments

- Miscellaneous procedures: cleaning, storage…

- Repair or replacement

- Particular instructions: for example, procedures in theevent of oil contamination, surge, heavy landing, handlingaccident, lightning...


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Training Notes

CORRECTIVE MAINTENANCE

OBJECTIVE OF CORRECTIVEMAINTENANCE

- To put the engine back into normal service as soon as possible

CORRECTIVE MAINTENANCEMAIN TASKS

- Fault finding

- Functional and condition checks

- Removal and installation

- Adjustments

- Miscellaneous procedures (cleaning, storage ...)

- Repair (or replacement)

- Particular instructions



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Training Notes

TECHNICAL PUBLICATIONS - GENERAL

This part deals with the engine technical documentation.

Operation documents

The operation documents are:

- The control documents (e.g.: flight manual)

- The management documents:• Engine log book (records and provides information

on the engine status).

Maintenance documents

- The current maintenance documents are the following (1st

and 2nd lines):• Maintenance manual (describes the engine and its

systems and all the maintenance procedures)

• Service bulletins (approved by the authorities, andissued to inform the operators of a modification or aninstruction which affects the operational aspects)

• Service letters (letter sent to inform the operator ofcertain instructions related to the operation of theengine)

• Modification index

- The deep maintenance instructions (3rd line):• Maintenance technical instructions

- The general overhaul and repair documents (4th line):• Overhaul manual• Standard practices manual• Work specification.

Identification documents

The identification documents are:

- The current maintenance documents:• Spare parts catalogue (list and reference of all the

spare parts)• Special tool catalogue (tool designations and

references)

- Overhaul and repair documents:• Illustrated Parts Catalogue (illustrates in detail all the

engine and accessory parts; only used for generaloverhaul)

• Descriptive list and drawings.

Note: Before all maintenance procedures:- It is mandatory to refer to official documentation- Use the documentation "in a rational way"- Make sure that documentation is up-to-date.


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Training Notes

TECHNICAL PUBLICATIONS - GENERAL

OPERATION

OVERHAULREPAIR

CURRENTMAINTENANCE

MANAGEMENTCONTROL

DOCUMENTS

MAINTENANCE IDENTIFICATION

CURRENT MAINTENANCE(1st and 2nd lines)

DEEPMAINTENANCE

(3rd line)

GENERAL OVERHAULREPAIR(4th line)

Example:Engine log book

Example:Flight manual

- Spare parts catalogue- Special tool catalogue

- IPC- Descriptive list

and drawings

- Maintenance manual- Service bulletins and letters- Modification index

Maintenance technicalinstructions

- Overhaul manual- Standard practices manual- Work specification



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Training Notes

TECHNICAL PUBLICATIONS - ADVISORYNOTICES

Three types of advisory notice are used in the technicalpublications:

- WARNING

- CAUTION

- NOTE.

Interpretation

WARNING: warns the reader of the possibility of physicalharm (e.g.: wounding, intoxication, electrocution).

CAUTION: warns the reader of the possibility of damagingthe engine or tooling.

NOTE: gives the reader advice on how best to carry out atask.

Examples

WARNING: do not breath the oil fumes. Do not leave oilin contact with the skin.

CAUTION: if the flush is being carried out because ofmetal particles in the oil system, change the filter andthoroughly clean the tank.

NOTE: take the oil sample before carrying out anyreplenishment.


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TECHNICAL PUBLICATIONS - ADVISORY NOTICES

Examples:

- Oil analysis- Cycle counting- Installation of O'ring seals- Engine storage- Insulation measurements- Procedural change with modification- ……

NOTE(advice)

Examples:

- Titanium part cleaning- Scrapping of O'ring seals- Use of the correct cleaning products- Engine cooling- Engine cleaning after use ofextinguishing product

- Orifice protection during removal- Borescope fragility- Tightening torque- ……

CAUTION(possibility of damage)

Examples:

- Toxicity of engine oil and vapours- Toxicity of cleaning products- Toxicity of extinguishing products- Eye protection- Fire risk- Electrical discharge from ignition units:

- electrocution- risks with use in an inflammable

atmosphere- ……

WARNING(physical harm)

14.1MAINTENANCE PROCEDURES

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14 - MAINTENANCE PROCEDURES

- General ................................................................... 14.2

- 1st line (O level )..................................................... 14.4

- 2nd line (I level )..................................................... 14.8

- 3rd line (H level ).................................................... 14.10

- 4th line (D level ) .................................................... 14.12 to 14.13

It is mandatory to refer to the approved and

current TURBOMECA maintenance technical publications

to carry out any maintenance procedure.



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Training Notes

MAINTENANCE PROCEDURES - GENERAL

This part is an introduction to the different maintenanceprocedures, which are described in the following pages fortraining purposes only.

These procedures are dealt with in discussion and practicalwork during a training course.

Procedures

- Definition

- Instructions and operating modes

List of procedures

- Standard practices

- Cautions

- Washing

- Miscellaneous checks

- Miscellaneous procedures

- Removal, installation

- Repair

- Adjustments

- ...

- Engine removal and installation

- Removal and installation of the accessories

- Module removal and installation

- Repair, general overhaul.

Note: It is mandatory to refer to refer to the approved andcurrent TURBOMECA maintenance technicalpublications to carry out any maintenanceprocedure.


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Training Notes

MAINTENANCE PROCEDURES - GENERAL




- Standard practices- Cautions- Washing- Miscellaneous checks- Miscellaneous procedures- Removal, installation- Repair- Adjustments- …

- Definition- Instructions and operating modes

PROCEDURES LIST OF PROCEDURES



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Training Notes

1ST LINE MAINTENANCE PROCEDURES(O LEVEL)

The 1st line maintenance procedures are described in theMaintenance Manual and can be carried out on the engineinstalled, in the airframe.

They include:

- Preventive maintenance procedures

- Corrective or unscheduled maintenance procedures(engine installed).

These 1st line procedures are listed in the following pagesin two groups:

- Check and servicing procedures

- LRU removal and installation procedures.

Consumable or repairable components

The accessories are considered as either consumable orrepairable.

Some accessories which are considered as consumable:fire detectors, start injector, igniter plug, ignition unit,speed sensors, filters, strainers, magnetic plug…

Note 1: LRU - Line Replaceable Unit.

Note 2: The accessories either have a TBO or are on-condition.

Note 3: It is mandatory to refer to refer to the approvedand current TURBOMECA maintenancetechnical publications to carry out anymaintenance procedure.


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3 screws on the support3 screws on the casing4 screws 4 screws on the casing2 screws on the flange3 screws2 screws on the support2 screws2 screws 2 screws Screwed onto the turbine casing3 screws on the filter support secured by a clamp3 screws on the support2 screws on the casingScrewed to the unit2 screws on the gearbox casing6 screws on the gearbox casingScrewed on the gearbox casing3 screws on the support2 screws on the casingClamps - screwsInstalled on the airframeHalf-clamps and 2 screws

2 screws on the plenumClamp4 parts secured by locking wire4 screws on the casingScrewed and bayonetScrewed on the gearbox casingScrewed on the gearbox casing

Fire detectorsAlternator - LP pumpOil-Fuel filter unitHP pump - Metering valveStop electro-valveValve assemblyStart electro-valveFlow dividerStart injectorsMain injectorsDrain valveFuel preblockage switchFuel pressure transmitterIgnition unitIgniter plugIgnition cableN1 sensorN2 sensorTorquemeter transmitterConformation boxThermocouplesElectrical harnessDigital Control UnitP3 sensor

T1 probeExhaust pipeHeat protectionOil pumpStrainers - Electrical magnetic plugs Min. oil pressure switchOil pressure transmitter

IDENTIFICATION ATTACHMENT

Polarity + or -

Do not remove the sleeves

WarningWarningWarningPossible adjustmentPossible adjustment

Colour codeColour code

Removal-installation when the unit is turned-offFrom the higher diameter,observe the tightening torque

Observe the tightening torque

Coupling sleeve

REMARKS




1ST LINE MAINTENANCE PROCEDURES (O LEVEL)



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Edition: May 2006

Training Notes

1ST LINE MAINTENANCE PROCEDURES(O LEVEL)

PRESERVATION AND STORAGE

General

When an engine is not used for a long time, it must beprotected against corrosive agents.

The most efficient preservation consists of:

- Washing and protecting the air path by spraying aspecific product

- Housing the engine in a waterproof container withdessicant bags.

If there is no container, the engine can be housed in a waterand vapour proof cover with dessicant bags.

Type of storage

"Short term" storage

Procedure which protects the engine for a duration of lessthan three months if the engine is not installed in thehelicopter.

"Long term" storage

Procedure which protects the engine for a duration ofmore than three months if the engine is not installed inthe helicopter. The engine is then inhibited in the package(in a wooden case or in metal container).

Engine installed in the aircraft

If the engine is installed in the aircraft:• When the engine is not used for less than 7 days,

install the air intake and exhaust blanking devicesand close the cowlings

• When the engine is not used between 7 days and 6months, drain and replace the oil, do a 5 minuteground run every 7 days

• When the engine is not used for more than 6 months,remove the engine and do the "long term" storageprocedure.

Storage inspection

Once the engine has been put into storage, it must beperiodically checked to ensure that it is in good condition.In the event of an anomaly, the preservation and storageprocedures must be renewed.

The max. duration of storage and inspection to be carriedout vary with the type of container used.

Note: Refer to maintenance manual for preservation andstorage procedures and periodicity.


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Training Notes

PRESERVATION AND STORAGE1ST LINE MAINTENANCE PROCEDURES (O LEVEL)

Refer to maintenance manual for preservation and

storage procedures and periodicity

GENERAL

- Protection against corrosive agents- Cleaning, internal and external protection

TYPE OF STORAGE

- "Short term": duration less than 3 months (protection covers)- "Long term": duration more than 3 months (storage in a wooden case or in a metal container)- Engine installed in the aircraft

STORAGE INSPECTION

- To be carried out periodically- Renewal of preservation and storage if necessary- Max. duration of storage and inspection to be carried out depend on the type of container used

PROCEDURES

- For engine installed in aircraft (less than 7 days or between 7 days and 6 months)- For uninstalled engines (3 months and more than 3 months)- Internal and external protection- System protection- Inhibiting products- Blanking devices- ...



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Training Notes

2ND LINE MAINTENANCE PROCEDURES(I LEVEL)

Modular designThe engine is of modular construction. This conceptavoids the return of the complete engine to a specializedworkshop and thus provides a higher operationalavailability and a reduction of maintenance costs.

Modular replacementEach module is a unit which can be replaced withoutbalancing or adaptation work.

However, some precautions must be taken when replacinga module. This page mentions the main points related tothis question:

- Reasons for module removal• Inspection (access to some components)• Replacement

- Module identification• Identification plate on module• Compatibility table• Engine log book

- Removal and installation conditions• Engine installed (or not) on the aircraft• Installation on working stand• Particular position (horizontal or vertical)

- Tools• Standard tools• Special tools

- Inspection after replacement• Ground run check• Condition checks• Functional checks• Performance checks

- Module follow-up• Engine log book

- Interfaces• Intermodular parts• Equipment• Mounting.

Note: Refer to Maintenance Manual.

Module M01 and M02 removal and installationThe procedure is carried out with a special tool with theengine in the vertical position and placed on module M02.

Power turbine module removal and installation(only 1M version)The procedure is carried out with a special tool with theengine in the vertical position and placed on module M02.

Note 1: In a training course, these procedures are dealtwith in video and practical sessions.

Note 2: It is mandatory to refer to refer to the approvedand current TURBOMECA maintenancetechnical publications to carry out anymaintenance procedure.


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Training Notes

2ND LINE MAINTENANCE PROCEDURES (I LEVEL)




MODULE M01 AND M02REMOVAL AND INSTALLATION

POWER TURBINE MODULE REMOVAL AND INSTALLATION (1M version)



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Training Notes

3RD LINE MAINTENANCE PROCEDURES(H LEVEL)

Definition

The 3rd line (or deep) maintenance procedures are carriedout on removed major parts (e.g. modules) in a workshop.

They consist of replacement or reconditioning ofsubassemblies without repair or adjustment (e.g. injectionwheel replacement).

Procedure

3rd Line Maintenance may be carried out on site byoperators, provided that the operator has been formallytrained, is in possession of the official updateddocumentation (maintenance technical instruction) andhas received the corresponding TURBOMECA approval(periodically renewable).


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3RD LINE MAINTENANCE PROCEDURES (H LEVEL)

3rd line maintenance may be carried out on site by operators,

provided that the operator has been formally trained, is in possession of the official updated

documentation (maintenance technical instruction) and has received the corresponding TURBOMECA approval (periodically

renewable).

3rd LINE MAINTENANCE (H Level)(engine removed)

- Deep maintenance



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Training Notes

4TH LINE MAINTENANCE PROCEDURES(D LEVEL)

REPAIR AND OVERHAUL

Overhaul

Overhaul is a major maintenance operation that must becarried out in a specific workshop when the engine (ormodule) has reached the end of its TBO or cyclic life.

The overhauled engine (or module) is then put back intoservice with zero hours for a new TBO.

Repair

Repair is a maintenance operation that must be carried outin a specific workshop when the engine (or module) isunserviceable or damaged.

After a repair, the engine (or module) is returned to servicewith a TBO according to the work carried out and theengine standard.

Note: TBO: Time Between Overhaul.

Main steps of 4th line maintenance

- Engine reception

- Disassembly

- Cleaning

- Inspection

- Investigation

- Repair

- Installation (of engine and accessories)

- Tests

- Delivery.


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Training Notes

REPAIR AND OVERHAUL

4TH LINE MAINTENANCE PROCEDURES (D LEVEL)

DISASSEMBLY - REPAIRACCESSORY ASSEMBLY

INSPECTIONCLEANING

ENGINE OR MODULEAT THE END OF TBO

OR FOR REPAIR

ENGINE OR MODULE DELIVERYAFTER OVERHAUL WITHFULL TBO, OR REPAIRED

DELIVERY

DISASSEMBLY

INVESTIGATION

ENGINEASSEMBLY

4TH LINEMAINTENANCE

WORKSHOP

TESTS

ENGINERECEPTION

REPAIR

15.1TROUBLE SHOOTING

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15 - TROUBLE SHOOTING

- General ................................................................... 15.2

- Trouble shooting ................................................... 15.4 to 15.23



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Training Notes

GENERAL

Introduction

Trouble shooting is a very important aspect of themaintenance.

Efficient diagnosis reduces the extra maintenance costsdue to unjustified removals and additional diagnosis time.

In fact, even with a very high reliability product, failure isinevitable and required actions should be taken efficiently.

After the fault analysis which consists of finding the effectof a given failure, this section considers the case in reverse;i.e.: finding the probable cause of a fault.

Repair procedure

The repair procedure should be guided by two mainconsiderations:

- A minimum downtime

- A justified removal of components.

The procedure to be applied depends on the case but, ingeneral, a good knowledge of the product and a methodicresearch would permit a safe diagnosis and a quickcorrective action.

In a general way, the procedure includes the failureidentification, its analysis, the isolation of the defectivecomponent, and the repair choice.


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Training Notes

GENERAL

Symptoms (and other additional indications…)All factors should be taken into considerationas well as the interactions.

Analysis of the fault

Identification of the faulty component

Additionalchecks

Deduction Substitution

Remedy(adjustment, replacement, cleaning, repair...)

Or otherperception

Fault(single, double,

dormant)

Inevitable Random

Trouble shooting

- Diagnosis- Remedy- Repair- Check

- Adequate means and procedures- Training of personnel

MTTR(Mean Time To Repair)

Total time requiredfor repairing



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Training Notes

TROUBLE SHOOTING - STARTING FAULTS (1)

Or fuel supplyanomaly

No effect after selecting startN doesn't increase

Is ventilationpossible?

- Circuit breaker, selector switch, relay- Digital Control Unit

- Starter contactor- Supply- Starter

Note

Note: Further tests (failure code, engaging noise of the contactor) help locate the failure.

Yes No

On selection of start, N increases, but no increase in t4.5

The ignitionsystem operates

(noise of HE components)

- Start electro-valve- Injectors

- HE ignition units- Igniters

Yes No

Note: Refer to the testprocedure in orderto discriminate

Possible start on1 injector (or 1 igniter)

Note: It is also possible to checkthe fuel flow through thecombustion chamber drain.

Fuel flow

Ignition system - Start electro-valve- Fuel supply

Yes No


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Training Notes

TROUBLE SHOOTING - STARTING FAULTS (2)

Abnormal t4.5

t4.5 ≈ 200°C

Other possibility: N and t4.5 increase, but no start

t4.5 > 200°Cbut not sufficient

t4.5 too high

Increase due to theinjectors, but themain system is notsupplied

- Digital Control Unit- Sensors- Drain valve of the combustion chamber

- Digital Control Unit, sensors, metering valve.- Fuel supply (LP circuit, filters...)

- Pressurising valve- Digital Control Unit

Note: In any case, check the electricalsupply (battery voltage).

Failure of the accessory drive shaft

Anomaly during starting acceleration

Too quick or too slowN1 increase

The starter is not cut-out at

self-sustaining speed

Abnormalidle speed

- Digital Control Unit- Fuel system

- Digital Control Unit- Starter contactor

- Abnormal t4.5- Starter system- Fuel system

Anomaly during accelerationfrom idle to nominal N

Acceleration withsurge

Acceleration(too slow

or no acceleration)No control

Control:- Electronic part- Hydromechanical part

Digital Control Unit orhydromechanical part




ARRIUS 1

Edition: May 2006

Training Notes

TROUBLE SHOOTING - FAULTS DURING SHUT-DOWN

Deceleration selected by moving the flightselector switch to the idle position

N1deceleration

Yes

Note: A crank with the power turbine fixed (rotorbreak allows) discrimination between the gasgenerator and the power turbine.

N1 stabilisationYes No

Select stop position

No

Yes

Correctrundown time

No

Abnormal rubbing of the rotating assembly

The engine shut-down can then beaffected by the manual fuel valveof the LP system. Further checkingrequired.

No

Normalshut-down

Yes

Fuel system

The engine stops N1 , t4.5

- Selector- Stop electro-valve

- Selector- Digital Control Unit


ARRIUS 1


Training Notes

TROUBLE SHOOTING - FAULT DURING DRY CRANK

Dry crank selection(press and hold)

N1 Indication

Yes

Gas generator rotates

No

Accessory drivetrain

Normaldry crank

Note: 20 sec. max. limit to avoidstarter overheat

NoYes

The starter turns

NoYes

N1 indicationIs startingpossible?

NoYes

- Starter- Starter contactor- 24V supply

Dry crankcontrol



ARRIUS 1

Edition: May 2006

Training Notes

TROUBLE SHOOTING - LUBRICATION FAULTS (1)

Abnormal oil pressure indication

VariationNo pressureLow High pressure

- Oil condition- Seal- Blockage inside the system

- Filter blockage indication- Pump valve

- Measuring system- Blockage of a jet

Low pressureindicator

Yes No

- Failure of the pump shaft- Pressure relief valve- Blockage inside the system- Large internal or external leak

Pressure indicating system:- Transmitter or- Indicator light


ARRIUS 1


Training Notes

TROUBLE SHOOTING - LUBRICATION FAULTS (2)

Abnormal temperature indication

HighLow

Yes No

- Measuring system- Insufficient cooling- Lubrication local anomaly, blockage of a jet

Measuring system

Abnormal oil consumption

Visible leak

External leak Internal leak

Pipe or accessoryseal on casing

Contamination of theaircraft air tapping

Smoke and oil evidencein the exhaust pipe

Oil contamination

Corrective actionDetection

According to the amount,origin and rate ofcontamination…

Magnetic plugAnalysisColor, aspect

- Leak from the hot section- Rear bearing housing, or defective pressurisation of the labyrinth seal.

- Leak from the cold section of the labyrinth seal- Rear bearing housing or pressurisation of the labyrinth seal.



ARRIUS 1

Edition: May 2006

Training Notes

TROUBLE SHOOTING - FAILURE LEADING TO ENGINE SHUT-DOWN IN FLIGHT

Unexpected shut-down

Yes

Actualoverspeed

No

Safety system: - Loss of signal - Electronic box

NoYes

Engine internalanomaly

N2, N1, C, t4.5, and oil pressure decrease

Operation of thepower turbine overspeed

safety

Fuel supply:- Pump shaft failure- Pipe rupture- Water in fuel- Digital control unit

Water or iceingestion

- Failure of the power transmission shaft- Control unit

Doubt

Rearming andcorrective actions

Note: In a twin engine configuration, the engine which remains in operation supplies the required power up to a certain limit.

Note: Unlikely


ARRIUS 1


Training Notes

TROUBLE SHOOTING - MISCELLANEOUS CASES (1)

- Blockage of the injection system- Fuel supply (pumps, filters...)- Digital Control Unit- Mode selector switch- T1 temperature probe

Yes

Max. N1 reached

No

Loss of power

- Torque and gas temperature indication- Engine: compressor fouling, turbine creep, ...

Note: Particular attention: check of the max. N1.

Abnormal gas temperature indication

Dirty compressor Engine internal problemMeasuring system

Compressor surge

Abnormally low Fluctuation Abnormally high

During start In operation

Engine problem(air intake, compressor...)




ARRIUS 1

Edition: May 2006

Training Notes


Gas generator speed - N1

Note: The total stabilisation of one engine, while the second engine is in normal operation, indicates a major failure ("fixed" metering valve).

Incorrectresponse time

- P3 supply to the Digital Control Unit- Gas generator

Overspeed


VariationsUnexpecteddeceleration

Unexpectedacceleration

- Anticipator- Wrong P3 and T1 signals to the Digital Control Unit- Digital Control Unit

- Wrong P3 and T1 signals to the Digital Control Unit- Mode selector switch- Fuel supply- Digital Control Unit- Abnormal operation of one of the fuel system accessories (refer to the chapter "fuel system")

- Air in the fuel system- Dirt in the fuel system- Constant P valve- Blockage of several main injectors- Digital Control Unit


ARRIUS 1


Training Notes


Power turbine speed - N2

Overspeed

- Failure of the transmission shaft- Control system

Incorrect speed

- N2 sensors- Indicators- Setting of the anticipator- Digital Control Unit- Abnormal operation of the gas generator

Vibration

Rotating assemblyof the gas generatoror the power turbine

Engine attachmentPower transmissionshaft

Engine - aircraftalignment



ARRIUS 1

Edition: May 2006

Training Notes


Instruments

Note: Failures which result in abnormal indication.

- Inaccurate indication (transmitter / receiver)- Systems associated with the engine

Refer to other cases

Fire "failure"Unexpected illumination Open circuit

No illumination in test mode Test system

Fire warningUnexpected illumination Bi-metallic strip broken

No illumination in test mode Test system

Indicator lights

Justified illumination

No illumination in the event of overheat

Overheat or fire

Reverse terminals + or -

Chip detection Unexpected illumination Sensor "sensibility"

No illumination despite the deposits Detectors

Justified illumination Particles on plug

Min. lubrication oil pressureMin. fuel pressure

Unexpected illumination Pressure switch

No illumination despite the pressure drop Pressure switch

Justified illumination Pressure drop

Oil filter pre-blockageUnexpected illumination Pressure switch

No illumination despite thedifferencial pressure increase

Pressure switch

Justified illumination Blockage

Fuel filter pre-blockage


ARRIUS 1


Training Notes


Note: Failures which result in abnormal indication

Overspeed rearmingUnexpected illumination N2 sensors

No illumination Overspeed system not rearmed

Air bleed prohibiting(if installed) Unexpected illumination DCU, interfaces

No illumination DCU, interfaces

Justified illumination Exceeded OEI 30 min. rating

Fixed metering valve(or major failure) Illumination not justified:

use the manual controlDCU

No illumination in case of a major failure:use the manual control

DCU

Justified illumination:use the manual control

DCU, sensors ...

Overspeed operationJustified illumination Overspeed

Unexpected illumination(at power on)

Overspeed system not rearmed

Minor failure

Illumination not justified DCU

Justified illumination Sensor, Digital Control Unitor serial data link(refer to the alphadigital code)

Loss of redundancy

Illumination not justified DCU

Justified illumination N1, N2 sensors; DCU supply(refer to the alphadigital code)



ARRIUS 1

Edition: May 2006

Training Notes

TROUBLE SHOOTING - FAULT FINDING

Introduction

We should note that a failure identification is easier whenan integrated system is used (Digital Control Unit andalphanumeric display; refer to chapter "CONTROL ANDINDICATION").

But a good knowledge of the engine and systems and amethodic research still remain necessary.

Procedure

An anomaly detected by the Digital Control Unit, isindicated by the amber or red GOV warning light.

To identify the failure, it is necessary to use thealphanumeric display. It is possible to choose the Memorymode for the faults occured during the last flight; Failureor Parameter modes for the faults in real time.

The problems are displayed with three codes: A xxxx, Bxxxx, C xxxx to which correspond three tables provided bythe flight manual and maintenance manual.

Another table provided by the maintenance manualsupplies the procedure to follow (see next page).


ARRIUS 1


Training Notes

TROUBLE SHOOTING - FAULT FINDING

Selectors lane+ Res.

TRIM lane +Selectors lane+ Res.

TRIM lane + Selectors lane+ Res. + Res.

TRIM lane

TRIM lane + Res.

TRIM lane + Res.

TRIM lane + Res.+ Res.

TRIM lane +Selectors lane

TRIM lane +Selectors lane+ Res.

No failure

Res.

Res.

Selectors lane

Selectors lane+ Res.

Res. + Res.

Selectors lane+ Res. + Res.

0

1

2

3

4

5

6

7

8

9

A

B

C

D

E

F

P3 lane +PITCH lane +T1 lane

No failure

PITCH lane

T4.5 lane

PITCH lane +T4.5 lane

T1 lane

PITCH lane +T1 lane

T4.5 lane +T1 lane

P3 lane +PITCH lane +T4.5 lane +T1 lane

P3 lane

P3 lane + PITCH lane

P3 lane + T4.5 lane

PITCH lane +T4.5 lane +T1 lane

P3 lane +PITCH lane +T4.5 lane

P3 lane + T1 lane

P3 lane + T4.5 lane+ T1 lane

0 No failure

1 Input mod.

2 Internal F.

Input mod. +internal F.

3

4 External F.

Input mod. +external F.

5

internal F. +external F.

6

Input mod. +Internal F. +external F.

7

8 Nil

9

A

B

C

D

E

F

0 No failure

1 Power mod.

2 Output mod.

Power mod. +output mod.

3

4 Airspeed mod.

Power mod. +speed mod.

5

output mod. +speed mod.

6

Power mod. +output mod. +speed mod.

7

8

9

A

B

C

D

E

F

0

1

2

3

4

5

6

7

8

9

A

B

C

D

E

F

Memory

Parameter

Failure

TESTNg

Ng TRIM

NR ADJ

SCROLL

ENGINE 2DCU

ENGINE 1DCU

ALPHANUMERICDISPLAY

ENGINE 1

ENGINE 2

ENGINE 2SENSORS

ENGINE 1SENSORS

INTEGRATED SYSTEM



ARRIUS 1

Edition: May 2006

Training Notes

TROUBLE SHOOTING - FAULT FINDING(CONTINUED)

Procedure (continued)

Example: A 4040 code or external failure (T1 probechannel).

A failure external to the DCU requires a check of thecorresponding harness and accessory (by means of anappropriate test box).

The DCU can be incriminated because the failure cancome from an external failure to the digital processingchannel (e.g.: interconnection unit).


ARRIUS 1


Training Notes

15 D TABLEDCU FAILURE PROCESSING

The DCU maintenance principle is as follows:1) Carefully look at the A-xxxx code; it will indicate in the column located after A- if the failure is internal or external:

- if it is an internal failure, replace the incriminated DCU,- if it is an external failure, the two last values ease fault finding.

2) The B-00xx code must be read after the A-xxxx code and ease maintenance (refer to associated procedures),3) The C-00xx code must be read after the A-xxxx code and ease maintenance (refer to associated procedures),

Split within tolerances indicated by the faultdisplay unit; resulting from a P0 differencebetween the 2 "Digital Control Units"

Inner fault on the outlet module

Light "on" without fault display

Without fault indication, there is no moredialog with the Control Unit

Lights "on" without fault indication

Fault code without light GOV; AMBER orRED

Particular case

Internal(s)

Internal(s)

Internal(s)

External(s)

Internal(s) or External(s)Internal(s) or External(s)Internal(s) or External(s)

Internal(s)

According to A-xxx code; internal or external

A-3000

X-xxxx

A-4000B-0001B-0002

A-1xxx

A-2xxx

A-3xxx

A-4040

A-5xxxA-6xxxA-7xxx

B-00x0

B-000x

The removed Digital Control Unit can bekept to check with another one having asimilar P0 difference

Minor fault light "on"



Test box ref. 8815800000



FAILURES ACTIONS OBSERVATIONSLIGHTS INDICATIONS

DIPO

EBUS

FUELandor

Compare P0 and QFE and change the ControlUnit with the greatest P0 difference

Standard exchange of the Control Unitconcerned by A-3000

Standard exchange of the Control Unit

Standard exchange of the Control Unit or faultdisplay unit


Standard exchange of the fault display unit

Standard exchange of the pump-metering valveunit and if the fault occurs again replace theDigital Control Unit




Check the harness and the sensor concernedtaking into account the tenth digit which canhelp in finding the channel anomaly (e.g. :A-4040 = T1 probe channel)

Apply the procedure for external faults A-4xxxthen if no result, replace the Digital Control Unit


AMBER GOV

RED GOV

AMBER & REDGOV

RED GOV

TROUBLE SHOOTING - FAULT FINDING (CONTINUED)

Exampleof codes for instruction

purposes only.In all cases, refer to

the maintenancemanual.



ARRIUS 1

Edition: May 2006

Training Notes

TROUBLE SHOOTING - DOCUMENTATION

Chapter 71.00.09 of the Maintenance Manual, which isdedicated to trouble shooting includes:

- A list of faults observed in operation

- A list of faults observed during maintenance

- A list of faults codes and their interpretation

- A list of trouble shooting tasks.


ARRIUS 1


Training Notes

TROUBLE SHOOTING - DOCUMENTATION

ARRIUS 1

CHAP. 71.00.09TROUBLESHOOTING

MAINTENANCEMANUAL

Trouble shootingtasks

Faultcodes

Maintenancefaults

Operatingfaults



ARRIUS 1

Edition: May 2006

Training Notes

TROUBLE SHOOTING - CONCLUSION

Despite the high reliability of the product, failures remaininevitable and happen at random. But their rate and effectscan be reduced if the "enemies" of the engine are taken intoconsideration.

When the failure occurs, you have to be in a position tocorrect it.

"Enemies" of the engine

The traditional adverse conditions for this type of engineare:

- Supply (oil, air, fuel, electricity):• Oil - Not in conformity with spec., contamination• Air - Sand, salt, pollution• Fuel - Not in conformity with spec., contamination• Electricity - Low voltage, connectors

- Operation ("non respect" of instructions and procedures)

- Maintenance ("non respect" of inspection frequencies,and of the strict application of the procedures).


ARRIUS 1


Training Notes

"ENEMIES" OF THE ENGINETROUBLE SHOOTING - CONCLUSION

- Not in conformitywith specifications

- Contamination

- Too low voltageduring starting

- Interference

MAINTENANCE

AIR

FUEL

- Not in conformity withspecifications

- Water in fuel- Sulphur + salt in the air =

sulfidation

OPERATION

- "Non respect" of instructionsand procedures

- Severe operating conditions

- "Non respect" of inspectionfrequencies

- Various mistakes- Wrong logistic

- Sand- Salt- Pollution

OIL

ELECTRICITY

16.1CHECKING OF KNOWLEDGEEdition: May 2006

Training Notes ARRIUS 1


16 - CHECKING OF KNOWLEDGE

- Introduction ........................................................... 16.2

- Questionnaire 1 ..................................................... 16.3

- Questionnaire 2 ..................................................... 16.6

- Questionnaire 3 ..................................................... 16.12

- Questionnaire 4 ...................................................... 16.15 to 16.17




INTRODUCTION

Method

Continuous checking helps to ensure the information isassimilated. It is more a method of work than a testing inthe traditional sense.

Objectives of the questionnaires

The questionnaires permit a progressive assimilation anda long term retention. The questionnaires are a subject fordiscussion (effects of group dynamics). They also permitstudents to consider important subjects several times underdifferent aspects.

Integration into the training programme

- First hour every day for revision of the subjects previouslystudied

- After each chapter (or module) of the course

- At the end of the training course.

Types of questionnaires

Several types of questionnaire can be employed during acourse:

- Traditional written questionnaire

- "Short answer" questionnaire

- Multi Choice Questionnaire (MCQ)

- Oral questionnaire

- Learning Through Teaching (LTT; the student has toexplain a given subject).

Examination

The final examination at the end of the course consists ofthree tests: written, oral and practical. A certificate and anapproval card are given to the student if the results aresatisfactory.




QUESTIONNAIRE 1

This traditional questionnaire is established according tothe same plan as the Training Notes in which the answerscan be found.

Turboshaft engine1 - List the main functional components of the power

plant.

2 - Explain the thermodynamic operation of the engine

3 - State the following characteristics (at take-off, instandard atmosphere):

• Power on the shaft

• Specific fuel consumption

• Compression ratio

• Gas generator turbine entry temperature

• Gas generator 100% rotation speed

• Nominal power turbine rotation speed

• Output shaft rotation speed

• Mass of the engine with specific equipment.

4 - Explain the principle of engine adaptation to helicopterpower requirements.

5 - Give a definition of the operating ratings.

6 - How do temperature and altitude affect the engineperformance.

Engine1 - List the main components of the gas generator.

2 - Describe the power turbine assembly.

3 - Describe the fuel injection system.

4 - List the engine driven accessories.

5 - List the bearings which support the gas generator.

6 - Describe the system used for the bearing sealing.

7 - Describe the reduction gear assembly.

8 - Describe the engine air intake.

9 - Describe how the modules are connected together.

10 - List the manufacturing materials of the engine maincomponents.




QUESTIONNAIRE 1 (continued)

Oil system1 - What type of system is it?

2 - At what pressure does the pressure warning light comeon?

3 - Describe the oil filter assembly.

4 - State the location of strainers and magnetic plugs.

5 - What is the max. oil consumption?

Air system1 - List the functions ensured by the internal air system

(secondary system).

2 - List the function of the various air bleeds.

3 - Why are the starting injectors ventilated?

4 - Explain the effect of air bleeds on engine performance.

Fuel system1 - Type of main fuel injection?

2 - Describe the low pressure fuel pump assembly.

3 - Function of the relief valve of the high pressure pump.

4 - Describe the fuel filter assembly.

5 - Explain the principle of fuel injection (main and startinginjection).

6 - What is the purpose of the constant ∆P valve.

7 - Give the operating procedure for manual fuel flowcontrol.

8 - Explain the operation of the system during starting.

Control system1 - List the main functions of the control system.

2 - Explain the basic principle of the control system.

3 - Explain the operating principle of the speed control.

4 - List the logic input signals of the DCU.

5 - List the analog input signals of the DCU.

6 - Describe and explain the operation of the overspeedsafety systems of the power turbine.

7 - Describe the Digital Control Unit.

Measurement and indicating systems1 - List the indicating systems of the power plant.

2 - Describe the rotation speed indicating system of thepower turbine.

3 - Explain the principle of the torquemeter system.

4 - Describe the t4.5 gas temperature indicating system.





Starting1 - Describe the cranking function of the engine.

2 - Describe the ignition system (ignition unit and igniterplugs).

3 - List the main phases of the starting cycle.

4 - Describe the starting control electrical system.

Electrical system1 - List the electrical control components.

2 - Indicate the alternator location.

3 - Describe the electrical harness and connectors.

Engine installation1 - Describe the attachment of the engine to the aircraft.

2 - Describe the engine power drive and the powertransmission.

3 - List the various engine / aircraft connections.

4 - Describe the fire protection system of the engine.

Maintenance1 - List the main operating limitations of the engine (explain

the reason for each limit).

2 - Describe the engine starting procedure.

3 - List the main practices of a preventive periodicinspection.

4 - List the means used for "on condition monitoring".

5 - Describe the procedure for engine removal.

6 - List the technical publications used for enginemaintenance.

7 - Do the "fault analysis" exercises.

8 - Do the "fault finding" exercises.




9 - Limit temperatures of the flightenvelope?

10 - Max. starting altitude?

11 - Engine mass?

12 - Max. gas temperature at the gasgenerator turbine entry?

13 - Air pressure at the compressoroutlet?

14 - Air temperature at the compressoroutlet?

15 - Gas generator 100% rotation speed?

16 - Type of compressor?

17 - Type of mounting of the powerturbine blades?

18 - Number of bearings which supportthe power turbine shaft?

19 - Number of bearings which supportthe output shaft?

QUESTIONNAIRE 2

The following questions require short and accurate answers.

The student can answer orally or in the space provided forthe answers.

Questions Answers

Questions Answers

1 - Location of the Digital ControlUnit?

2 - Direction of rotation of the powerturbine?

3 - Engine air flow?

4 - Power turbine nominal rotationspeed?

5 - Direction of rotation of the gasgenerator?

6 - Power on the shaft at take off rating?

7 - MTOP rating max. use duration?

8 - OEI 2 min. 30 sec. rating max. useduration?




30 - Setting of the oil filter by-passvalve?

31 - Type of oil pressure transmitter?

32 - Location of the low oil pressureswitch?

33 - Oil pressure illuminating theindicator light?

34 - How many oil pumps?

35 - Location of the oil temperatureprobe?

36 - Filtering ability of the oil filter?

37 - Type of oil pumps?

38 - Setting of the oil filter pre-blockageswitch?

39 - Max. oil consumption?


Questions Answers Questions Answers

20 - Location of the centrifugalbreather?

21 - Number of power turbine bearings?

22 - Type of seal on the power shaft?

23 - Manufacturing material for thecompressor?

24 - Number of stages of the gasgenerator turbine?

25 - Number of accessory drives?

26 - Number of bearings which supportthe gas generator?

27 - Overall compression ratio?

28 - Type of combustion chamber?

29 - Is the oil pressure adjustable?




50 - Start injector flow?

51 - Number of main injectors?

52 - Position of the fuel pump pressurerelief valve in normal operation?

53 - Location of the alternator?

54 - Number of gas generator rotationspeed sensors?

55 - Number of thermocouple probes?

56 - Number of power turbine rotationspeed sensors?

57 - Location of the torquemeter?

58 - Torquemeter average pressure at100%?

59 - Type of connection of thethermocouples.

40 - Air bleed for the power turbinebearing pressurisation?

41 - Air bleed characteristics?

42 - Number of start injectors?

43 - Position of the combustion chamberdrain valve engine stopped?

44 - Setting of the combustion chamberdrain valve?

45 - Fuel specific consumption (atcruise rating)?

46 - Type of main fuel injection?

47 - Position of the stop electro-valve atengine shut-down?

48 - Position of the main metering valvein case of an electronic failure?

49 - Type of LP fuel pump?






60 - Overspeed safety setting of thepower turbine?

61 - Type of ignition?

62 - Max. duration of a ventilation?

63 - Gas generator speed at starter cut-off?

64 - Max. and min. temperatures of thestarting envelope?

65 - Min. electrical voltage at starting?

66 - Number of engine electricalharnesses?

67 - Number of fire sensors?

68 - Is borescope inspection of thecombustion chamber possible?


Questions Answers

69 - Procedure to be carried out if theengine is not expected to operate formore than 7 days?

70 - Rundown check during engineshut-down:- Time?

- Noises?

71 - Tolerance to apply to periodicinspections?

72 - Method to record the engine hours?from …… to ……

73 - Is the removal-installation of thepower shaft seal possible in currentmaintenance?

74 - Document stating the basic andindividual TBO's?

75 - Definition of a complete engine cycle?

76 - Definition of a partial cycle?

Questions Answers





84 - Is it necessary to remove thecentering sleeve when replacing astart injector?

85 - Procedure for cleaning the airtapping union restrictors?

77 - Stabilisation time before engineshut-down?

78 - Is a vibration check to be carried outwith only one engine in operation ?

79 - Procedure to be applied in the caseof chip indicator "on" followed by adrop of engine power?

80 - What are the parameters affectingthe oil pressure?

81 - Setting of the combustion chamberdrain valve (expressed in N1)?

82 - How is the N1 speed sensor gapadjusted?

83 - Is the fuel filter pre-blockagepressure switch an LRU?





QUESTIONNAIRE 3

This multi-choice questionnaire is used to review, in arelatively short time, certain important points and to testthe acquired knowledge.

Answers to the questions are to be found at the end of thequestionnaire.

1 - The ARRIUS 1 engine is:a) a free turbine turboshaft engineb) a turbo-jet enginec) a fixed turbine turboshaft engine.

2 - Section of passage of the compressor diffusers:a) regularb) divergentc) convergent.

3 - Type of combustion chamber:a) annular with centrifugal injectionb) annular, reverse flowc) annular, indirect flow.

4 - The power turbine shaft belongs:a) to the reduction gearboxb) to the power turbinec) to the gas generator.

5 - Type of exhaust pipe attachment:a) boltsb) mounting padsc) clamp.

6 - Number of bearings which hold the gas generator:a) 4b) 2c) 3

7 - The output shaft belongs to:a) gas generatorb) power turbinec) reduction gearbox.

8 - Type of oil system:a) dry sumpb) constant pressurec) lubrication by splashing.

9 - Setting of the oil filter pre-blockage switch:a) lower than the by-pass valveb) higher than the by-pass valvec) the same as the pump valve.

10 - The oil strainers are located:a) at the outlet of the pumpsb) on the suction side of the scavenge pumpsc) at the inlet of the lubricated components.

11 - Is there a max. oil temperature:a) yes, 60°Cb) noc) yes, 110°C max.





12 - The air bled from the outlet of the centrifugalcompressor wheel is used for the pressurisation of:a) some labyrinth sealsb) the tankc) the pumps.

13 - The balance piston is balanced by:a) air bled from the middle of the centrifugal

compressorb) air bled from the outlet of the compressor wheelc) air bled from the outlet of the centrifugal compressor

diffuser.

14 - Type of ambient air temperature probe?a) platinum probeb) nickel probec) thermocouple.

15 - Ventilation of starting injectors:a) does not existb) is made with air from the compressorc) is made with atmospheric pressure air.

16 - The manual metering valve:a) does not control the metering unitb) controls the metering unit mechanicallyc) controls the metering unit electrically.

17 - The maximum rotation speed of the gas generator:a) is set by the control systemb) is set by a mechanical stopc) there is no maximum speed.

18 - The signature box is part of:a) the torque indicating systemb) the temperature indicating systemc) does not exist.

19 - With the anticipator, the static droop is:a) compensatedb) cancelledc) overcompensated.

20 - Type of Digital Control Unit:a) hydraulicb) analogc) digital electronic.

21 - The thermocouples are installed:a) in seriesb) in parallelc) on the turbine casing.

22 - The conformation box is used for:a) the synchronisationb) the torquemeter operationc) the gas temperature measurement.





23 - Number of thermocouples?a) 2 x 4b) 2 x 5c) 2 x 3

24 - Number of N2 signals?a) 2b) 6c) 3

25 - Number of N1 signals?a) 3b) 4c) 6

26 - The starter cut-out is made:a) automaticallyb) manuallyc) with air pressure.

27 - Starting is possible with one igniter:a) yesb) noc) yes, in emergency.

28 - HE ignition means:a) Hot Electrodeb) High Energyc) High Emission.

29 - Borescopic inspection is used to check:a) the external parts conditionb) the internal parts condition which are not accessible

without removalc) the reduction gearbox condition.

30 - The reliability of the engine is:a) goodb) fairly goodc) extremely good.

1 - a6 - b

11 - c16 - a21 - b26 - a

Answers

2 - b7 - c

12 - a17 - a22 - c27 - a

3 - b8 - a

13 - c18 - c23 - a28 - b

4 - b9 - a

14 - a19 - a24 - b29 - b

5 - c10 - b15 - b20 - c25 - a30 - abc?




QUESTIONNAIRE 4

This questionnaire is a sort of drill which is also used to testand perfect the knowledge acquired.

1 - List the reference stations (numbers) on the illustrationbelow:

2 - Complete this table (with values):

3 - Engine description - List the components on the diagram:

1 - ................................ 3 - ................................

2 - ................................ 4 - ................................

Ratings shp N1 N2kW

2 min. 30sec.

5 min.

30 min.

1 2 3 4





4 - Oil system - Name the components on the diagram:

1 - .......................... 2 - .......................... 3 - ......................... 4- ..........................

5 - .......................... 6 - .......................... 7 - ......................... 8- ..........................

1

2

3

4

5

6

7 8





5 - Air system - Indicate (with different colours) thefollowing air circuits:

a) pressurisation of turbine bearing seals

b) pressurisation of the segments

c) pressurisation of the balance piston

d) cooling of turbine NGV.

6 - Fuel system - Name the components:

1 - .................................................................................

2 - .................................................................................

3 - .................................................................................

4 - .................................................................................

5 - .................................................................................

6 - .................................................................................

5

6

1

2

3

4





7 - Fuel system - Name the components of the meteringunit assembly:

1 - ................................................................................

2 - ................................................................................

3 - ................................................................................

2

1

3

END

but not the END of your t ra iningwhich must be cont inued (again and again)

harmonizing knowledge and experience.

THANK YOU for your kind at tent ion.

of these training notes and (maybe also) of the course

Au revo i rGood bye

Ad iósAuf Wiedersehen

AdeusAr r i vederc i

Fa r ve lTo t z i ens

A d j öNäkemi in

A n t i oMa sa laam

Se lamat Ja lan

TURBOMECA Training Centre

REMARKS CONCERNING THE TRAINING AIDS REMARKS CONCERNING THE TRAINING COURSE

Name ....................................................................................................................................... .

Address .................................................................................................................................... .

Course .............................................................. from............................ to ............................. .

REMARKS

Remarks (appreciations, criticisms, suggestions...) should be forwarded to:

TURBOMECACENTRE D'INSTRUCTION40220 TARNOS - FRANCE

Documents

Manual Entrenamiento Arrius Ia