Manual Entrenamiento Arrius Ia

Training Notes

ARRIUS 1

FOREWORD This document is intended to assist a TURBOMECA qualified instructor in teaching basic information related to the operation and maintenance of the ARRIUS 1 turboshaft engine. It is a training aid and should only be used to support the training course to which it refers and only by a person attending such training. It must not be used in any other circumstances. It will not be updated and should not be relied upon for maintenance or repair of ARRIUS 1 engines. Only the approved and current TURBOMECA maintenance technical publications should be used for such purposes. The acquisition of this document does not constitute proof of official formal training. Only completion of a course delivered by a TURBOMECA qualified instructor can lead to the issuance of a TURBOMECA recognized training course certificate, 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. For training purposes only © Copyright - TURBOMECA

0.1 Edition: May 2006

FOREWORD

Training Notes

ARRIUS 1

SUMMARY 9 - Starting

0 - Foreword 1 - Introduction

10 - Electrical system

2 - Power plant

11 - Engine installation

3 - Engine

12 - Operating limitations and procedures

4 - Oil system

13 - Various aspects of maintenance

5 - Air system

14 - Maintenance procedures

6 - Fuel system

15 - Trouble shooting

7 - Control system 8 - Measurement and indicating systems

For training purposes only © Copyright - TURBOMECA

16 - Checking of knowledge

0.2

Edition: May 2006

SUMMARY

ARRIUS 1

Training Notes

TABLE OF CONTENTS 0 - FOREWORD -

Summary ............................................ Table of contents ................................ List of abbreviations .......................... Conversion table ................................

3 - ENGINE -

0.2 0.3 0.7 0.10

1 - INTRODUCTION -

General information ........................... Training method ................................. Training aids ...................................... Training programme .........................

1.2 1.4 1.6 1.8 to 1.14


3.2 3.8 3.10 3.16 3.22 3.28 3.34 3.38 3.40 3.46 to 3.51

4 - OIL SYSTEM

2 - POWER PLANT - Power plant ........................................ • General ........................................... • Description ..................................... • Operation ....................................... - Principle of adaptation to the helicopter ........................................... - Main characteristics ........................... - Design and development ...................

Engine ................................................ Air intake ........................................... Compressor ........................................ Combustion chamber ......................... Gas generator turbine ......................... Power turbine ..................................... Exhaust system .................................. Reduction gearbox ............................. • Reduction gear train ....................... • Accessory drive train ......................

-

2.2 2.2 2.4 2.6

Oil system ......................................... Oil reservoir ....................................... Oil pumps ........................................... Oil filter.............................................. Pre-blockage pressure switch .............

4.2 4.8 4.10 4.14 4.20

2.10 2.12 2.18 to 2.21

0.3

Edition: May 2006

TABLE OF CONTENTS

ARRIUS 1

Training Notes

TABLE OF CONTENTS (CONTINUED) 6 - FUEL SYSTEM

4 - OIL SYSTEM (CONTINUED) -

Cooling unit ....................................... Centrifugal breather ........................... Electrical magnetic plugs ................... Strainers ............................................. Low oil pressure switch ..................... Oil pressure transmitter ...................... Oil temperature probe ........................ Oil pipes .............................................

-

4.22 4.24 4.26 4.28 4.30 4.32 4.34 4.36 to 4.37

5 - AIR SYSTEM -

Air system ......................................... Internal air system ............................. Air tappings........................................ Air tapping unions ............................. Air pressure sensor............................. Air temperature probe ........................


5.2 5.4 5.6 5.8 5.10 5.12 to 13

Fuel system ....................................... Fuel pressure transmitter .................... LP fuel pump - Alternator unit ........... Fuel filter............................................ Pre-blockage pressure switch ............. HP fuel pump and metering unit ........ Stop electro-valve .............................. Fuel valve assembly ........................... Start injectors ..................................... Main injectors .................................... Combustion chamber drain valve ...... Fuel pipes ...........................................

6.2 6.16 6.18 6.24 6.30 6.32 6.38 6.42 6.48 6.54 6.60 6.62 to 6.63

7 - CONTROL SYSTEM - Control system ................................... • General ........................................... • Description ..................................... • Operation ........................................

7.2 7.2 7.4 7.6


TABLE OF CONTENTS

ARRIUS 1

Training Notes

TABLE OF CONTENTS (CONTINUED) 7 - CONTROL SYSTEM (CONTINUED)

9 - STARTING - Starting system ................................... - Starter ................................................. - Ignition system ................................... • Ignition unit .................................... • Igniter plugs .................................... • Ignition cables ................................

- Digital Control Unit .................................. 7.34 •General .................................................... 7.34 •Functional description ............................. 7.36 to 7.39

8 - MEASUREMENT AND INDICATING SYSTEMS - Measurement and indicating systems ....... - Speed measurement and indicating system ................................................ 8.4 •N1 speed sensor....................................... •N2 speed sensors ..................................... - Gas temperature measurement and indicating system ...................................... •Thermocouple probes and t4.5 conformation box .................................... - Torque measurement and indicating system ....................................................... •Torque transmitter ................................... - Miscellaneous indications ......................... •Indicators ................................................. •∆N1 measurement and indicating system ...... •Display system ........................................ For training purposes only © Copyright - TURBOMECA

8.2

9.2 9.6 9.10 9.12 9.14 9.16 to 9.17

10 - ELECTRICAL SYSTEM - Electrical system ................................ 10.2 - Alternator ........................................... 10.4 - Electrical harnesses ............................ 10.6 to 10.7

8.6 8.10

11 - ENGINE INSTALLATION 8.14 8.16 8.20 8.24 8.26 8.26 8.28 8.30 to 8.33

-

Engine compartment .......................... Engine mounting and lifting .............. Power drive ........................................ Air intake ........................................... Exhaust system .................................. Drain system ...................................... Fire protection ....................................

11.2 11.4 11.6 11.8 11.10 11.12 11.14 to 11.15


TABLE OF CONTENTS

ARRIUS 1

Training Notes

TABLE OF CONTENTS (CONTINUED) 12 - OPERATING LIMITATIONS AND PROCEDURES

15 - TROUBLE SHOOTING - General ............................................... 15.2 - Trouble shooting ................................ 15.4 to 15.23

- Operating limitations ......................... 12.2 - Operating procedures ........................ 12.4 to 12.7

16 - CHECKING OF KNOWLEDGE 13 - VARIOUS ASPECTS OF MAINTENANCE -

Maintenance concept ......................... Life limitation .................................... Preventive maintenance ..................... "On-condition" monitoring ................ Corrective maintenance ..................... Technical publications .......................

13.2 13.4 13.6 13.8 13.10 13.12 to 13.15

14 - MAINTENANCE PROCEDURES -

General ............................................... 1st line (O level) ................................ 2nd line (I level) ................................. 3rd line (H level) ................................ 4th line (D level) ................................


14.2 14.4 14.8 14.10 14.12 to 14.13

-

Introduction ........................................ Questionnaire 1 ................................. Questionnaire 2 ................................. Questionnaire 3 ................................. Questionnaire 4 ..................................

16.2 16.3 16.6 16.12 16.15 to 16.17

OBSERVATIONS ..................................... Last page These training notes are established to meet training requirements and take into consideration, to a certain extent, ATA 104 specifications. This document has 397 pages. It was produced using a desktop publishing system


TABLE OF CONTENTS

Training Notes

ARRIUS 1

LIST OF ABBREVIATIONS The abbreviations / symbols shown below may be used during training: A/C ............... AC ................. ACW ............. ADP .............. AEO .............. ATA .............. BITE ............. C ................... cc/h ............... CDS .............. CFT ............... CH ................. CW ................ dB ................. DC ................. DGAC ........... DMC ............. Ec .................. EECU ............

Aircraft Alternating Current Anti-clockwise Aero Design Point All Engines Operating Air Transport Association Built In Test Equipment Torque Cubic centimetres per hour Cockpit Display System Frequency/Voltage Converter Fuel consumption Clockwise Decibel Direct Current Direction Générale de l'Aviation Civile Direct Maintenance Cost Kinetic energy Engine Electronic Control Unit


EGT .............. F .................... FAA .............. FADEC ......... FCU .............. ft .................... FLI ................ FOD .............. FWD ............. G ................... HE ................. HP ................. HP ................. hPa ................ HUMS ........... Hz ................. ID .................. ILS ................ IRAN ............

Exhaust Gas Temperature Frequency Federal Aviation Agency Full Authority Digital Engine Control Fuel Control Unit Feet First Limit Indicator Foreign Object Damage Forward Mass air flow High Energy Horse Power High Pressure Hecto Pascal Health and Usage Monitoring System Hertz Identification Integrated Logistic Support Inspect and Repair as Necessary


LIST OF ABBREVIATION

Training Notes

ARRIUS 1

LIST OF ABBREVIATIONS (CONTINUED)

ISA ................ kHz ............... kPa ................ kW ................ lb ................... lb/hr ............... lb/sec. ............ lb/HP.hr ........ LCD .............. LP ................. LRU .............. LTT ............... LVDT ........... m ................... mA ................ MAX ............. MCP .............. MCQ ............. MGB ............. MHz .............. MIN ..............

International Standard Atmosphere Kilohertz Kilopascal Kilowatt Pound Pounds per hour Pounds per second Pounds per Horse Power per hour Liquid Crystal Display Low Pressure Line Replaceable Unit Learning Through Teaching Linear Voltage Differential Transducer Metre Milliampere Maximum Max. Continuous Power Multi Choice Questionnaire Main gearbox Mega Hertz Minimum


mm ................ MTBF ........... MTBUR ........ mV ................ N ................... N1 ................. N2 ................. NOVRAM .... NR ................. O/S ................ OEI ............... P .................... P3 .................. PH ................. POS ............... PT ................. Q ................... RAM ............. ROM ............. RPM .............. RTD ..............

Millimetre Mean Time Between Failure Mean Time Between Unscheduled Removal Millivolt Rotation speed Gas generator rotation speed Power turbine rotation speed Non Volatile Read Only Memory Rotor rotation speed Overspeed One Engine Inoperative Pressure Compressor outlet pressure Oil pressure Position Power Turbine Fuel flow Random Access Memory Read Only Memory Revolutions Per Minute Resistive Temperature Device



ARRIUS 1

Training Notes

LIST OF ABBREVIATIONS (CONTINUED)

SFC ............... PSI ................ PSID ............. Shp ................ SI ................... t ..................... T/O ................ TBO .............. TET ............... t° ................... t°4.5 ............. t°H................. US G ............. VAC .............. VDC .............. VEMD ..........

Specific Fuel Consumption Pounds per Square Inch Pounds per Square Inch Differential Shaft horse power International System Time Take-Off Time Between Overhaul Turbine Entry Temperature Temperature Gas temperature Oil temperature US Gallon Volt, Alternating Current Volt, Direct Current Vehicle and Engine Multifunction Display


W .................. Z .................... Zp ..................

Power Altitude Pressure altitude

°C .................. °F .................. °K .................. ± .................... ≈ .................... Ω ................... µP .................. ∆ .................... ∆P ................. % ................... < .................... > ....................

Degrees Celsius Degrees Fahrenheit Degrees Kelvin Positive and negative for electrical circuits Approximately Ohm Micro-processor Difference Pressure difference Percent Is lower than Is higher than



ARRIUS 1

Training Notes

CONVERSION TABLE UNITS

International System

Length

1 mm 1m

= =

0.039 inch 3.28 ft = 1.09 yard

Volume

1 dm3 = 1 litre

=

0.26 US gallon

Mass

1 kg

=

2.2 lbs

Power

1 kW

=

1.34 HP

Temperature

°C °K

= =

(°F-32). 5/9 [(°F-32)5/9] + 273

Pressure

1 kPa = 0.01 bar

=

0.145 PSI

Flow (air, oil, fuel)

1 kg/s

=

2.2 lbs/sec.

Specific Fuel Consumption

1 g/kW.h

=

0.00164 lb/HP.hr


British or American Systems


CONVERSION TABLE

Training Notes

ARRIUS 1

1 - INTRODUCTION - General information............................................... 1.2 - Training method ..................................................... 1.4 - Training aids ........................................................... 1.6 - Training programme ............................................. 1.8 to 1.14



INTRODUCTION

ARRIUS 1

Training Notes

Training Centre

GENERAL INFORMATION

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

«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.

TARNOS ..

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

Address ....

TURBOMECA - 40220 TARNOS FRANCE

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 ...

www.turbomeca-support.com "T.O.O.L.S." (Turbomeca Operator OnLine Support).

"Greater knowledge leads to greater efficiency".

Objectives of training The main objective is the acquisition of the knowledge required for the tasks to be achieved (know and know how). Further information is also communicated to widen the skill and the experience of the trainee.

Training approach - Performance based training according to task analysis, with classroom sessions, student involvement, practical work and troubleshooting techniques - Advanced training aids: training notes, Computer Aided Presentation (or overhead projection), multimedia courseware and demonstration mock-ups - Experienced and formally trained instructors - Courses are taught in English and French and, in special circumstances, in German and Spanish.


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

Training sites Training courses are also conducted in subsidiaries, in approved 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.


INTRODUCTION

ARRIUS 1

Training Notes

TRAINING OBJECTIVES OF TRAINING

«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.

TRAINING APPROACH

"Greater knowledge leads to greater efficiency".

TRAINING CENTRE, TURBOMECA Tarnos (FRANCE)

FRANCE ATLANTIC OCEAN

TARNOS BAYONNE BORDES

SPAIN

PARIS

TRAINING SITES Training courses are also conducted in subsidiaries, in approved training centres and on site.

GENERAL INFORMATION For training purposes only © Copyright - TURBOMECA


INTRODUCTION

Training Notes

ARRIUS 1

TRAINING METHOD Knowledge transmission process

Training method

The required knowledge is transmitted in such a manner that the student may use it efficiently in various circumstances.

The training method is a carefully balanced combination of: - Lecture

The training is conducted in accordance with a process which considers:

- Exercises

- A phase of explanation for understanding

- Discussions

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

- Practical work.

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



INTRODUCTION

ARRIUS 1

Training Notes

EXPLANATION

ASSIMILATION

1 KNOWLEDGE TRANSMISSION, PHASES:

2

MEDIA

3

4

- Explanation - Assimilation CHECKING OF KNOWLEDGE: - Continuous checking, treated in chapter 16

1 - LECTURE 2 - EXERCISES 3 - DISCUSSIONS 4 - PRACTICAL WORK

INSTRUCTOR

STUDENT

KNOWLEDGE TRANSMISSION PROCESS

TRAINING METHOD

TRAINING METHOD For training purposes only © Copyright - TURBOMECA


INTRODUCTION

Training Notes

ARRIUS 1

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

Computer Aided Presentation

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

Computer Aided Presentation consists of a file which allows the illustrations contained in the training notes to be projected via a computer.

The information contained in the training aids is intended for training purposes only. It is not a substitute for the official TURBOMECA maintenance technical publications. Refer to the approved and current TURBOMECA maintenance technical publications to carry out any maintenance procedure.

Training notes The training notes are the basic source of information.

The Computer Aided Presentation replaces the transparencies which were used before to display these same illustrations

Multimedia courseware The multimedia courseware is Computer based Training software following the training notes layout. It gives information in a teaching and interactive manner. This multimedia system uses text, photos, illustrations, sounds, animation and video. Questionnaires are also used for check-up of knowledge.

They contain, in a teaching form, all required information and explanations based on the layout specified in standard ATA 104. Each subject is thus dealt with according to a plan which allows the information to be adapted to different levels of training:

It forms the essential support of training courses and ensures their uniformity.

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

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

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

- Description (general and detailed) - Operation (phases, synthesis).

Demonstration mock-ups

Other technical publications are also used during a course.

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



INTRODUCTION

ARRIUS 1

Training Notes

COMPUTER AIDED PRESENTATION

TRAINING NOTES

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 issuance of 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 a substitute for the official TURBOMECA maintenance technical publications. Refer to the approved and current TURBOMECA maintenance technical publications to carry out any maintenance procedure.

DEMONSTRATION MOCK-UPS

MULTIMEDIA COURSEWARE

TRAINING AIDS For training purposes only © Copyright - TURBOMECA


INTRODUCTION

Training Notes

ARRIUS 1

TRAINING PROGRAMME The course programme is established to meet training requirements and takes into consideration ATA 104 specifications. It should be noted that the "classroom sessions" alternate with periods devoted to demonstrations, practical exercises and visits.

Examples of programme: The following pages provide examples of training programme: - Familiarization course - 1st line maintenance (O level): preventive and corrective maintenance - 2nd line maintenance (I level): modules, SRU - 3rd line maintenance (H level): deep maintenance - Refresher - Trouble shooting - Fuel and control system - Engine documentation.



INTRODUCTION

Training Notes

ARRIUS 1

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

- Introduction - General presentation of the engine

FIRST DAY

- Engine description - Engine systems

- Engine systems (continued)

SECOND DAY

- Main aspects of maintenance - Revision - Checking of knowledge



INTRODUCTION

Training Notes

ARRIUS 1

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 to explain the operation of the engine and its systems, to carry out maintenance procedures (engine installed in the airframe) and trouble shooting. Programme:

- Introduction - General

FIRST DAY - Engine presentation - Engine description - Oil system - Air system - Fuel system - Control system - Indication - Starting

SECOND DAY - Electrical system - Engine installation - Operating limitations and procedures

THIRD DAY - Various aspects of maintenance - Pratical work

FOURTH DAY

- Pratical work - Trouble shooting

FIFTH DAY

- Visits - Revision - Examination - Course conclusion



INTRODUCTION

Training Notes

ARRIUS 1

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 the maintenance procedures (engine removed from the airframe), mainly the removal/installation of modules and shop replaceable units. Programme:

The programme mainly includes practical work. This programme can be carried out after the 1st line maintenance programme.

- Introduction

FIRST DAY

- Revision (if this course is not conducted directly after the 1st line course) - Removal of modules - Inspection and check of modules - Installation of modules

SECOND DAY


- Inspection and checks after installation


INTRODUCTION

Training Notes

ARRIUS 1

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. The course 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 FROM 3 DAYS TO 3 WEEKS

- Definition of procedures - Practical work



INTRODUCTION

Training Notes

ARRIUS 1

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

FIRST DAY SECOND DAY

- Introduction - Revision of the 1st line maintenance course - Revision (continued) - Fleet situation - Engine evolution - Course conclusion

Note: This course is recommended for technicians who have attended the first line maintenance course, after about 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 all engine systems - Fault finding and rectification - Fleet situation - Engine evolution - Course conclusion

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



INTRODUCTION

Training Notes

ARRIUS 1

FUEL AND CONTROL SYSTEM Objective: At the end of this course, the trainee will have an in-depth understanding of the engine fuel and control systems. Programme:


- Introduction - Fuel and control systems - Measurement and indicating systems - Engine evolution - Course conclusion

Note: This course is recommended for technicians who have attended the first line maintenance course, after about one year of experience on the engine type. ENGINE DOCUMENTATION Objective: At the end of this course, the trainee will be able to understand and use the engine documentation. Programme:


- Introduction - Presentation of the engine documentation - Exercises - Course conclusion

Note: A general knowledge of engines is recommended. For training purposes only © Copyright - TURBOMECA


INTRODUCTION

Training Notes

ARRIUS 1

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



POWER PLANT

Training Notes

ARRIUS 1

POWER PLANT - GENERAL Function

Main components

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

- Turboshaft engine with specific equipment - Digital Control Unit (DCU).

Main characteristics - Type: free turbine turboshaft engine with integral reduction 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 pipe and DCU.



POWER PLANT

ARRIUS 1

Training Notes POWER PLANT

Type: Free turbine turboshaft engine with integral reduction gearbox and front power drive Concept: Modular Mass dry: 111.5 kg (246 lbs) with "specific equipment" AIR

GAS

DIGITAL CONTROL UNIT (DCU) POWER

AIR

FUEL

Power: 350 kW class (470 Shp) Output shaft rotation speed: 6016 RPM (at 100% N2)

POWER PLANT - GENERAL For training purposes only © Copyright - TURBOMECA


POWER PLANT

Training Notes

ARRIUS 1

POWER PLANT - ENGINE DESCRIPTION This description considers the engine main functional components.

Exhaust pipe - Exhaust pipe mounted on the turbine casing flange.

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 generator shaft.



POWER PLANT

ARRIUS 1

Training Notes

REDUCTION GEARBOX ACCESSORY DRIVE TRAIN

GAS GENERATOR AIR INTAKE

CENTRIFUGAL COMPRESSOR

COMBUSTION CHAMBER

TURBINE

REDUCTION GEAR TRAIN

MAIN POWER DRIVE

POWER TURBINE

EXHAUST PIPE

POWER PLANT - ENGINE DESCRIPTION For training purposes only © Copyright - TURBOMECA


POWER PLANT

Training Notes

ARRIUS 1

POWER PLANT - OPERATION This part deals with the basic operation of the engine.

Power turbine

Reduction gearbox

- Gas expansion in the single stage power turbine to drive the main power drive through the reduction gear train.

- The reduction gear train provides a reduced speed output for the main power drive - The accessory drive train drives the various engine accessories.

Digital Control Unit - Control and monitoring of the engine operation.

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 flow annular combustion chamber - Gas expansion in the single stage axial turbine to drive the centrifugal compressor and the various engine accessories.



POWER PLANT

ARRIUS 1

Training Notes REDUCTION GEARBOX ACCESSORY DRIVE

POWER DRIVE

GAS GENERATOR AIR ADMISSION

COMPRESSION

COMBUSTION

EXPANSION

AIR

GAS

FUEL EXPANSION DIGITAL CONTROL UNIT (engine control and monitoring)

POWER TURBINE

POWER PLANT - OPERATION For training purposes only © Copyright - TURBOMECA


POWER PLANT

Training Notes

POWER PLANT - OPERATION ADAPTATION

ARRIUS 1

Power turbine

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

Component adaptation

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

For the engine operation, two functional assemblies can be considered:

Operation

- The gas generator which provides kinetic energy - The power turbine which transforms this kinetic energy into mechanical power on a shaft.

The operation is represented by the diagram below which shows the power W, the rotation speeds N1 and N2 and the max. torque limit C imposed by the mechanical transmission. - The torque C is a function of the N2 rotation speed (the torque is an inverse function of the speed)

The two assemblies have different rotation speeds. Gas generator

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

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 the centrifugal compressor outlet

- At constant N2 speed, the power is only a function of the torque - The engine parameters can be represented as a function of a reference parameter; N1 for example.

- 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 PLANT

ARRIUS 1

Training Notes GAS GENERATOR

POWER TURBINE

C

N1

(shaft torque)

(rotation speed)

G

Ec

(air mass flow)

(kinetic energy)

N2 (constant rotation speed)

W (shaft power)

P3, t3

TET

(compressor outlet pressure and temperature)

(turbine entry temperature)

Q (fuel flow)

W

ENGINE PARAMETERS

C ue

t x. Ma

q or

Isospeeds N1

G

W=C. = 2 N 60

0 /P 3 P W

CH T TE

SFC

N2 Power W and speeds N1, N2

N2 Torque C as a function of N2

N1 P3/P0: Compression ratio CH: Hourly fuel consumption SFC : Specific fuel consumption

POWER PLANT - OPERATION - ADAPTATION For training purposes only © Copyright - TURBOMECA


POWER PLANT

Training Notes

ARRIUS 1

PRINCIPLE OF ADAPTATION TO THE HELICOPTER Power transmission

Installation requirements

The mechanical power supplied by the engine, is used to drive the helicopter rotors through a mechanical transmission.

The main functional requirements of the installation are: - Constant rotation speed NR in all operating conditions - Max. torque limit C (usually imposed by the mechanical transmission)

This power drives: - The main rotor (approximately 82%) - The tail rotor (approximately 10%)

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

- The main gearbox (approximately 8%).

- Good load sharing in twin-engine configuration.

Power plant installation (twin-engine configuration)

Adaptation to requirements

The engines are installed at the rear of the main gearbox. The power turbines of the two engines are mechanically connected to the main gearbox which drives the rotors (main and tail rotors).


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


POWER PLANT

ARRIUS 1

Training Notes MAIN GEARBOX

MAIN ROTOR 82%

TAIL ROTOR

ENGINE 2

ENGINE 100%

ENGINE 1

MAIN GEARBOX 8%

TAIL ROTOR 10%

MAIN ROTOR

POWER TRANSMISSION

TWIN-ENGINE CONFIGURATION

N2

Power - W

NR ∆W

N1, N2, TET... ENGINE

∆N2 ∆N2 Time

Max. torque (C)

∆t

INSTALLATION REQUIREMENTS

ADAPTATION TO REQUIREMENTS

PRINCIPLE OF ADAPTATION TO THE HELICOPTER For training purposes only © Copyright - TURBOMECA


POWER PLANT

Training Notes

ARRIUS 1

MAIN CHARACTERISTICS (1) Engine ratings The operational ratings correspond to given conditions of helicopter operation. The ratings are generally defined under determined speed and atmosphere conditions (altitude and temperature).

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

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 limited duration (5 minutes continuous) • Max. Continuous Power (MCP): rating which can be used without time limitation (this does not imply that it 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 engine failure during take-off or landing. This rating is usually limited to a period of continuous operation (2 minutes 30 seconds, 15 minutes max. cumulated) • OEI 30 min. (Intermediate Contingency Power): rating which can be used in the case of one engine failure in flight. This rating is usually limited to 30 minutes.



POWER PLANT

ARRIUS 1

Training Notes

W A.E.O. RATINGS

O.E.I. RATINGS OEI 2 min. 30 sec.

MTOP 5 min.

OEI 30 min.

MCP Continuous

ENGINE RATINGS

MAIN CHARACTERISTICS (1) For training purposes only © Copyright - TURBOMECA


POWER PLANT

Training Notes

ARRIUS 1

MAIN CHARACTERISTICS (2) Operational performance The values given are min. performance in determined conditions: - ISA condition, sea level

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

- No air bleed - On test bench with no air intake and exhaust losses - Under specified N1 speeds (those corresponding to the ratings). Power (W): power available on the engine output shaft considering the corresponding torque limitation. It is expressed in kilowatt (kW) or Shaft horse power (Shp).



POWER PLANT

ARRIUS 1

Training Notes

ARRIUS 1A: example of values Power Ratings

Max. N1 rotation speed in RPM

kW

Shp

OEI 2 min. 30 sec.

388

520

56119

103.7%

OEI 30 min.

357

478

55307

102.2%

MTOP (5 min.) *

340

456

54658

101%

MCP

296

397

53305

98.5%

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

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

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

OPERATIONAL PERFORMANCE



POWER PLANT

Training Notes

ARRIUS 1

MAIN CHARACTERISTICS (3) Engine operating envelope

Limitations

The engine is designed to operate within a given climatic envelope.

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

The envelope is defined by:

Refer to corresponding chapters and official publications.

- 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 and the lines of standard atmosphere, with the max. tropical zone and the min. arctic zone. Engine starting and relight envelope The starting and relight envelope is defined in the same way, but it is also affected by the specifications of oil and fuel used, and sometimes by particular instructions.



POWER PLANT

ARRIUS 1

Training Notes

ALTITUDE Zp

ALTITUDE Zp

6100 m (20000 ft) STARTING LIMIT

MAX PICA

. TRO L

NORMAL ENVELOPE

E

R PHE

ARTIC

MOS

D AT

MIN.

R NDA STA

5000 m (16400 ft)

ENVELOPE ENLARGEMENT WITH PARTICULAR INSTRUCTIONS

0 m (0 ft) -500 m (-1640 ft)

0 m (0 ft) +50°C TEMPERATURE t0 (+122 °F)

-50°C (-89.6 F)

-500 m (-1640 ft)

FLIGHT ENVELOPE

-50°C (-89.6°F)

-20°C (-4°F)

+50°C TEMPERATURE t0 (+122°F)

ENGINE STARTING AND RELIGHT ENVELOPE

ENGINE OPERATING ENVELOPE



POWER PLANT

Training Notes

ARRIUS 1

DESIGN AND DEVELOPMENT (1) Design principles

Development steps

The engine is designed to meet the aircraft propulsion requirements and particularly for the new generation of helicopters.

The main steps of engine development are: - September 1981: launch

The engine design is based on:

- 1983: pre-qualification tests (50 h)

- An optimised thermodynamic cycle which allows high performance

- May 1983: first flight

- Simple and reliable components giving a good supportability, and a good maintainability to reduce the costs.

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

Engine designation ARRIUS - According to Turbomeca tradition: name of a Pyrenean lake.

Engine development The ARRIUS 1 engine is based on the research and experience of other engines: - First generation engines: ASTAZOU, ARTOUSTE and TURMO

- 1: Type - A: Variant - 1: Version

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



POWER PLANT

ARRIUS 1

Training Notes

Engine design

Optimised thermodynamic cycle

ARRIUS 450 Shp

TM 333 850 Shp

MTR 390 1200 Shp

RTM 322 2100 Shp

Simple and reliable components ARRIEL 650 - 700 Shp

Supportability Maintainability

High performance

Cost reduction

ASTAZOU 500 - 1000 Shp

MAKILA 1700 - 1800 Shp

ARTOUSTE 400 - 850 Shp

TURMO 1500 - 1600 Shp

DESIGN PRINCIPLES ENGINE DEVELOPMENT STEPS

1987 D.G.A.C. certification

ARRIUS lake

1983 1st Flight

1981 Launching

TIME

DEVELOPMENT STEPS

Example: ARRIUS: 1: A: 1:

ARRIUS 1A1 Pyrenean lake Type Variant Version

ENGINE DESIGNATION

DESIGN AND DEVELOPMENT (1) For training purposes only © Copyright - TURBOMECA


POWER PLANT

Training Notes

ARRIUS 1

DESIGN AND DEVELOPMENT (2) Application

Engine fleet status

The ARRIUS 1 engine is designed for the following applications:

In ......, we can note: - Number of engines produced: ...

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

- Operating hours: ...

- Twin engine AS 555 Fennec: ARRIUS 1M.

Maintenance concept The ARRIUS 1 is designed to provide a high availability rate with reduced maintenance costs. The main aspects of the maintenance concept are the following: - 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.



POWER PLANT

ARRIUS 1

Training Notes

Arrius 1A - E

Arrius 1M

Twin engine AS 355 Squirrel

Twin engine AS 555 Fennec

MAINTENANCE CONCEPT

FLEET STATUS

- 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.

- Number of engines produced - ARRIUS 1 operating hours

DESIGN AND DEVELOPMENT (2) For training purposes only © Copyright - TURBOMECA


POWER PLANT

Training Notes

ARRIUS 1

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. For training purposes only © Copyright - TURBOMECA


ENGINE

Training Notes

ARRIUS 1

ENGINE - GENERAL Function

Main components

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

- Reduction gearbox (reduction gear train and accessory drive train)

Main characteristics

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

- Type: free turbine, integral reduction gearbox and front power drive

- Power turbine.

- 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.



ENGINE

ARRIUS 1

Training Notes

ACCESSORY DRIVE TRAIN

CENTRIFUGAL COMPRESSOR

TURBINE

POWER TURBINE

Type Free turbine, integral reduction gearbox and front power drive Gas generator (N1) 54117 RPM (100%) - ACW Power turbine (N2) 45438 RPM (100%) - CW Output shaft 6016 RPM (100% N2) - CW

AIR INTAKE

COMBUSTION CHAMBER

REDUCTION GEAR TRAIN

ENGINE - GENERAL For training purposes only © Copyright - TURBOMECA


ENGINE

ARRIUS 1

Training Notes

ENGINE - DESCRIPTION Main functional components

Modular layout

- Reduction gearbox • Reduction gear train • Accessory drive train

The engine comprises 2 modules:

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

- Module M01: Reduction gear train and accessory drive train - Module M02: Gas generator (air intake, centrifugal compressor, combustion chamber and turbine) and power turbine. Note 1:

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

A module is a sub-assembly which can be replaced on-site (2nd line maintenance) without complex tooling or adaptation work. Each module has an identification plate. The engine identification plate is fitted on the face of the reduction gearbox casing.

Note 2:

Some accessories are provided with each module. In these training notes, those components are dealt with in the chapters corresponding to the main systems.



ENGINE

ARRIUS 1

Training Notes Engine identification plate

M01 module identification plate

M02 module identification plate

M02 MODULE GAS GENERATOR AND POWER TURBINE

M01 MODULE REDUCTION GEARBOX

ENGINE - DESCRIPTION For training purposes only © Copyright - TURBOMECA


ENGINE

Training Notes

ARRIUS 1

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

Compression The ambient air is compressed by a single stage centrifugal compressor. 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 combustion chamber, mixed with the fuel and burnt in a continuous process. 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 temperature rise (flame temperature approx. 2500°C; 4530°F) and a pressure drop of about 4%.


Expansion - In the gas generator turbine which extracts the energy required to drive the compressor (N1 speed: 54117 RPM at 100%, ACW). During this phase, the gas pressure and temperature drop whilst the velocity increases - In the power turbine which extracts most of the remaining energy to drive the power drive through the reduction gearbox (N2 speed: 45438 RPM at 100%, CW). After the expansion through the power turbine, the gas are discharged overboard through an outlet diffuser and a divergent exhaust pipe. The expansion phase goes on and the gas are expelled overboard with a slight residual forward thrust. Note: The engine reference stations are: 1 - Ambient air 2 - Compressor inlet 3 - Compressor outlet 4 - Gas generator turbine inlet 4.5 - Gas generator turbine outlet 5 - Power turbine outlet.


ENGINE

ARRIUS 1

Training Notes Primary air (combustion air)

FUEL

AMBIENT AIR 1.6 kg/s (3.5 lbs/sec.)

Secondary air (dilution air)

Residual thrust

Gas 2500°C (4532°F) EXHAUST ROTATION SPEED

Gas generator 54117 RPM (100%) - ACW Power turbine 45438 RPM (100%) - CW

1

2

3

4

861 (125)

4.5

T°C (°F)

101.3 (14.6)

320 (608)

ADMISSION

Compressor

230 (33.3) 800 (1472)

15 (59)

Values given for information at a given reference rating

826.5 (120)

1000 (1832) P kPa (PSI)

5

Combustion chamber

COMPRESSION COMBUSTION

100 (14.5)

Turbines

Exhaust EXPANSION

ENGINE - OPERATION For training purposes only © Copyright - TURBOMECA


ENGINE

Training Notes

ARRIUS 1

AIR INTAKE Function The air intake directs the ambient air into the centrifugal compressor.

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

Operation

Position

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

- At the front of the centrifugal compressor.


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

- 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 is annular with a parallel passage. It is secured by a ring of bolts to the rear casing of the reduction gearbox at the front and to the centrifugal compressor front cover and the intermediate casing at the rear. The internal hub of the 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 of them has an orifice for borescopic inspection. It is secured around the air intake casing.



ENGINE

ARRIUS 1

Training Notes

Type Annular Air flow 1.6 kg/s (3.5 lbs/sec.)

MOUNTING FLANGE (on air intake casing)

ENGINE AIR INTAKE CASING

AIR INTAKE GUARD

STREAMLINED STRUT

FRONT BEARING

NORMAL SUPPLY

10 mm ORIFICE (compressor washing borescopic inspection)

BY-PASS SUPPLY

COMPRESSOR WASHING DEVICE (optional)

AIR INTAKE GUARD

SUPPLY UNION

AIR INTAKE For training purposes only © Copyright - TURBOMECA


ENGINE

Training Notes

ARRIUS 1

COMPRESSOR - GENERAL Function

Main components

The centrifugal compressor provides the compressed air required for combustion.

- Rotating component (centrifugal wheel)

Position

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

- At the rear of the air intake casing.

Main characteristics - Type: centrifugal, single stage - Overall compression ratio: approx. 8.5 - Rotation speed: N1; ACW.



ENGINE

ARRIUS 1

Training Notes

INTERMEDIATE CASING

DIFFUSER ASSEMBLY

Type Centrifugal, single stage Overall compression ratio approx. 8.5 Rotation speed N1; ACW

CENTRIFUGAL WHEEL

FRONT COVER

COMPRESSOR - GENERAL For training purposes only © Copyright - TURBOMECA


ENGINE

Training Notes

ARRIUS 1

COMPRESSOR - DESCRIPTION The centrifugal compressor assembly includes rotating and stationary components.

The stationary assembly includes the casings and the diffuser assembly.

Rotating components The main rotating component is the centrifugal impeller. The wheel has blades which are cut from the solid in a disc of titanium alloy. The rear part has a curvic-coupling for the connection to the gas generator turbine. The wheel is mounted on the gas generator shaft.

Stationary components

The compressor front cover houses the centrifugal compressor and is provided with an abradable coating which gives a reduced clearance. The cover fits into the air intake casing. It is bolted to the intermediate casing by means of a ring of bolts. The diffuser assembly comprises the first stage diffuser formed by radial stator vanes and the second stage diffuser formed by axial stator vanes. The rear cover of the diffuser assembly separates the compressor from the combustion chamber. It is bolted to the intermediate casing by a ring of bolts. The intermediate casing ensures the mechanical connection between the air intake casing and the external casing.



ENGINE

ARRIUS 1

Training Notes

FRONT COVER (provided with an abradable coating)

INTERMEDIATE CASING

DIFFUSER ASSEMBLY

DIFFUSER ASSEMBLY REAR COVER

FRONT COVER

AIR INTAKE CASING

CENTRIFUGAL IMPELLER

AIR INTAKE CASING

INTERMEDIATE CASING

GAS GENERATOR SHAFT

CENTRIFUGAL IMPELLER (titanium impeller with blades cut from the solid)

CURVIC-COUPLING

COMPRESSOR - DESCRIPTION For training purposes only © Copyright - TURBOMECA


ENGINE

Training Notes

ARRIUS 1

COMPRESSOR - OPERATION The compressor ensures the compression stage.

Compressor air flow The air from the air intake flows into the centrifugal compressor. The air flows between the blades of the centrifugal compressor. The air pressure increases due to the divergent passage between the blades and the air velocity increases due to the centrifugal flow. The air leaves the tips of the blades at a very high velocity and then flows through the first stage diffuser vanes where the velocity reduces and the pressure increases. The air then passes through an elbow and the flow becomes axial. In the second stage diffuser, the velocity is again reduced and the pressure increased. This air is then admitted into the combustion chamber.



ENGINE

ARRIUS 1

Training Notes AIR ACCELERATION AND COMPRESSION

AIR ADMITTED INTO THE COMBUSTION CHAMBER

AIR ADMISSION AIR STRAIGHTENING AND COMPRESSION

COMPRESSOR - OPERATION For training purposes only © Copyright - TURBOMECA


ENGINE

Training Notes

ARRIUS 1

COMBUSTION CHAMBER - GENERAL Function

Main components

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

- Flame tube - Inner and outer elbows

Position

- External casing.

- Central section of the gas generator.

Main characteristics - Type: annular, reverse flow - Overall fuel/air ratio: 1/45.



ENGINE

ARRIUS 1

Training Notes

EXTERNAL CASING OUTER ELBOW

INNER ELBOW

FLAME TUBE

Type Annular, reverse flow Overall fuel/air ratio 1/45

COMBUSTION CHAMBER - GENERAL For training purposes only © Copyright - TURBOMECA


ENGINE

Training Notes

ARRIUS 1

COMBUSTION CHAMBER - DESCRIPTION The combustion chamber assembly includes the external casing, the flame tube, the external and internal elbows and the fuel injection system.

External casing

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

Inner elbow

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

The inner elbow is mounted on the turbine nozzle guide vane.

There is also a borescope port for inspection.

Fuel injection system

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

- The start fuel injection is ensured by 4 simple injectors located on the combustion chamber casing, 2 are close to the igniter plugs

Flame tube The flame tube is made of special alloy. It forms an enclosure in which the fuel/air mixture is burnt. It has numerous calibrated orifices for the passage of air.

- The main fuel injection is ensured by nine main injectors and a "preference" injector, all located on the rear face of the combustion chamber casing. The injectors penetrate into T-shaped tubes welded at the rear of the flame tube.

The flame tube fits in the outer and inner elbows by sliding contacts. It is maintained inside the external casing and centered by the igniter plug housings and two centering pins.

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

Note: The calibrated orifices are drilled using the electron beam process.



ENGINE

ARRIUS 1

Training Notes

FLAME TUBE INNER ELBOW (with nozzle guide vane)

EXTERNAL CASING

START INJECTOR

IGNITER PLUG

VAPORISER TUBE

OUTER ELBOW

INNER ELBOW VAPORISER TUBE

NOZZLE GUIDE VANE

OUTER ELBOW FLAME TUBE

MAIN INJECTOR

COMBUSTION CHAMBER - DESCRIPTION For training purposes only © Copyright - TURBOMECA


ENGINE

Training Notes

ARRIUS 1

COMBUSTION CHAMBER - OPERATION The combustion chamber forms an enclosure in which the fuel/air mixture is burnt.

Flow in the combustion chamber In the combustion chamber, the compressed air is divided into two flows: a primary air flow mixed with the fuel for combustion and a secondary air flow (or dilution air flow) for cooling. Primary air The primary air flows through the calibrated orifices of the flame tube and through the hollow vanes of the turbine nozzle guide vane (cooling of the vanes). In the flame tube, the primary air is mixed with the fuel sprayed by the injectors. The combustion occurs inside the flame tube. The flame temperature reaches approx. 2500°C (4530°F). Secondary air The secondary air (or dilution air) flows through the orifices of the flame tube. It is calibrated to obtain flame stability, cooling of the gas and an even distribution of temperature on the turbine. Gas The gas flow rearward through the combustion chamber elbow and then through the turbine nozzle guide vane.



ENGINE

ARRIUS 1

Training Notes

PRIMARY AIR (combustion)

COMPRESSED AIR

SECONDARY AIR (dilution)

COMBUSTION 2500°C (4530°F)

GAS FUEL INJECTION

GAS DIRECTED TO THE TURBINE

COMBUSTION CHAMBER - OPERATION For training purposes only © Copyright - TURBOMECA


ENGINE

Training Notes

ARRIUS 1

GAS GENERATOR TURBINE - GENERAL Function

Main components

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

- Rotating components (wheel, shaft, bearing) - Stationary components (nozzle guide vane, intermediate diffuser, containment shield…).

Position - At the rear of the gas generator.

Main characteristics - Type: axial, single stage turbine with uncooled inserted blades - Rotation speed: N1; ACW.



ENGINE

ARRIUS 1

Training Notes

CONTAINMENT SHIELD

SHAFT

WHEEL

Type Axial, single stage turbine with uncooled inserted blades

BEARING

Rotation speed N1; ACW

INTERMEDIATE DIFFUSER

NOZZLE GUIDE VANE

GAS GENERATOR TURBINE - GENERAL For training purposes only © Copyright - TURBOMECA


ENGINE

Training Notes

ARRIUS 1

GAS GENERATOR TURBINE - DESCRIPTION The gas generator turbine assembly includes rotating and stationary components.

Rotating components The main rotating component is the turbine wheel. The wheel consists of a disc with fir-tree mounted single crystal blades. At the front, the wheel is coupled to the centrifugal compressor shaft by a curvic-coupling. The rear part of the gas generator is supported by a roller bearing. Rotating labyrinth seals ensure the sealing of the bearing. A nut at the rear secures the turbine wheel labyrinth and bearing to the gas generator shaft.

Stationary components The main stationary components are the turbine nozzle guide vane, the containment shield and the intermediate diffuser. The turbine nozzle guide vane includes a row of hollow vanes through which the cooling air flows. It is bolted to the combustion chamber inner part and to the containment shield. The containment shield is located around the turbine wheel to ensure its containment in case of blade failure. The intermediate diffuser ensures the gas flow from the gas generator to the power turbine. Its internal hub houses the gas generator rear bearing. The diffuser also includes struts which house the lubrication tubes for the rear bearings.

A balance piston is located on the front of the turbine wheel.



ENGINE

ARRIUS 1

Training Notes TURBINE BLADE (fir-tree root)

GAS GENERATOR SHAFT

LABYRINTH SEAL (rear)

REAR BEARING (roller)

TURBINE WHEEL SECURING NUT

BALANCE PISTON NOZZLE GUIDE VANE

TURBINE NOZZLE GUIDE VANE (hollow vanes)

CONTAINMENT SHIELD

INTERMEDIATE DIFFUSER

GAS GENERATOR SHAFT

CURVIC-COUPLING (with compressor)

BALANCE PISTON

TURBINE WHEEL (inserted blades)

ROLLER BEARING

GAS GENERATOR TURBINE - DESCRIPTION For training purposes only © Copyright - TURBOMECA


ENGINE

Training Notes

ARRIUS 1

GAS GENERATOR TURBINE - OPERATION The gas generator turbine transforms the kinetic energy contained in the gas into mechanical power required to drive the compressor and the engine accessories.

Turbine gas flow The gas from the combustion chamber first flows through the nozzle guide vanes. The gas velocity increases due to the convergent passage. The flow over the turbine blades results in aerodynamic forces whose resultant causes the rotation of the wheel and drives the compressor and the engine accessories. The gas, still containing energy, is directed to the power turbine through the intermediate diffuser.



ENGINE

ARRIUS 1

Training Notes GAS FROM THE COMBUSTION CHAMBER

NOZZLE GUIDE VANE Rotation

COMPRESSOR AND ACCESSORY DRIVE

Nozzle guide vane

Turbine wheel

GAS DIRECTED TO THE POWER TURBINE TURBINE WHEEL ROTATION

GAS GENERATOR TURBINE - OPERATION For training purposes only © Copyright - TURBOMECA


ENGINE

Training Notes

ARRIUS 1

POWER TURBINE - GENERAL Function

Main components

The power turbine extracts the energy which remains in the gas to drive the power drive through the reduction gear train.

- Rotating components (wheel, shaft, bearing) - Stationary components (nozzle guide vane, containment shield, casing, internal hub, bearing cage).

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

Main characteristics - Type: axial, single stage, one piece wheel (or disc and fir-tree mounted blades after TU71) mounted on the power turbine shaft - Rotation speed: N2; CW.



ENGINE

Training Notes

ARRIUS 1

POWER TURBINE CASING

CONTAINMENT SHIELD INTERNAL HUB

Type Axial, single stage, one piece wheel (or disc and fir-tree mounted blades after TU71) mounted on the power turbine shaft

BEARING CAGE

Rotation speed N2; CW

SHAFT

WHEEL

BEARING

POWER TURBINE NOZZLE GUIDE VANE

POWER TURBINE - GENERAL For training purposes only © Copyright - TURBOMECA


ENGINE

Training Notes

ARRIUS 1

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

Stationary components The main stationary components are the nozzle guide vane, the containment shield and the casing.

Rotating components The main rotating component is the turbine wheel. It is a one piece wheel ( or disc and fir-tree mounted blades after TU71) mounted on the power turbine shaft. The power turbine shaft is supported by a ball bearing (squeeze film bearing) housed in the intermediate diffuser internal hub. Rotating labyrinth seals ensure the bearing sealing. The power turbine shaft passes through the hollow shaft of the gas generator. At the front, it has splines for the mounting of the reduction gear train drive gear.

The nozzle guide vane forms a one piece assembly of vanes located between external and internal rings. The containment shield is located around the external ring of the nozzle guide vane. It ensures the blade containment in case of blade breaking. The power turbine casing is bolted to the gas generator external casing. It is formed by an outer case and an inner case connected by four hollow struts. Two struts house the oil tubes for the lubrication of the power turbine bearing and the gas generator turbine bearing. The internal hub supports the bearing cage. The lubrication tubes are screwed into the internal hub. The internal hub is secured at the rear to the power turbine casing. The bearing cage supports the power turbine ball bearing and the gas generator roller bearing.



ENGINE

ARRIUS 1

Training Notes SECURING NUT (to secure the bearing on the shaft)

TURBINE SHAFT

POWER TURBINE WHEEL

POWER TURBINE CASING

POWER TURBINE CASING POWER TURBINE BEARING (ball bearing)

BEARING CAGE

LUBRICATION TUBE CONTAINMENT SHIELD

POWER TURBINE NOZZLE GUIDE VANE

PHONIC WHEEL

INTERNAL HUB

SPLINES (to drive the input gear of the reduction gear train)

POWER TURBINE

INTERNAL HUB

BEARING CAGE

POWER TURBINE BALL SHAFT BEARING

LABYRINTH SEALS

POWER TURBINE - DESCRIPTION For training purposes only © Copyright - TURBOMECA


ENGINE

Training Notes

ARRIUS 1

POWER TURBINE - OPERATION The power turbine transforms the gas energy provided by the gas generator into mechanical power to drive the power drive through the reduction gear train.

Power turbine flow The gas supplied by the gas generator flows first through the nozzle guide vane in which the velocity increases due to the convergent passage. The gas is directed onto the turbine wheel and the resultant of the aerodynamic forces on the blades causes the wheel to rotate and drive the power drive through the reduction gear train. The gas is then expelled overboard through the exhaust pipe.



ENGINE

ARRIUS 1

Training Notes GAS FROM THE GAS GENERATOR TURBINE

NOZZLE GUIDE VANE

GAS EXPELLED OVERBOARD

Rotation

Nozzle guide vane

REDUCTION GEAR TRAIN DRIVE

Turbine wheel

POWER TURBINE WHEEL ROTATION

POWER TURBINE - OPERATION For training purposes only © Copyright - TURBOMECA


ENGINE

Training Notes

ARRIUS 1

EXHAUST SYSTEM - GENERAL Function

Main components

The exhaust system continues the expansion phase and expels the gas overboard.

- Exhaust pipe - Extension

It also ensures the axial containment of the power turbine wheel.

- Mounting clamp (M02 module)

Position

- Heat shield

- Behind the power turbine.


- Oil system vent pipe - Central cone.

- Type: axial, exhaust pipe with extension - Replaceable non modular component.



ENGINE

ARRIUS 1

Training Notes

Type Axial, exhaust pipe with extension Replaceable non modular component OIL SYSTEM VENT PIPE

CENTRAL CONE

MOUNTING CLAMP (M02 module)

EXHAUST PIPE

EXHAUST PIPE

EXTENSION

HEAT SHIELD

EXHAUST SYSTEM - GENERAL For training purposes only © Copyright - TURBOMECA


ENGINE

Training Notes

ARRIUS 1

EXHAUST SYSTEM - DESCRIPTION OPERATION Description

Operation

The main components of the exhaust system are:

The gas are expelled overboard through the divergent passage of the exhaust diffuser and exhaust pipe. They still have a certain amount of energy causing a slight residual thrust.

The exhaust pipe which is a sheet metal worked assembly. It includes a central cone which improves the gas flow and reduces the residual thrust. The exhaust pipe has bosses for the drain unions and a boss for the oil system vent pipe. The venturi extension which increases the cooling air flow through the engine compartment by venturi effect.

The exhaust system collects the oil system general air vent. The gap between the exhaust pipe and the extension improves the engine compartment ventilation.

The mounting clamp which secures the exhaust pipe to the turbine casing rear part. Note: The central cone is design to ensure the axial containment of the power turbine wheel.



ENGINE

ARRIUS 1

Training Notes

Oil system vent pipe POWER TURBINE

Engine compartment air suction by Venturi effect

CLAMP

GAS EXHAUST

CENTRAL CONE

EXHAUST PIPE

EXTENSION

EXHAUST SYSTEM - DESCRIPTION - OPERATION For training purposes only © Copyright - TURBOMECA


ENGINE

Training Notes

ARRIUS 1

REDUCTION GEARBOX General

Main components

Function

- Front and rear casings

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

- Reduction gear train

Position

- Accessories installed on the reduction gearbox.

- Accessory drive train

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



ENGINE

ARRIUS 1

Training Notes


FRONT CASING

POWER DRIVE 6016 RPM (100% N2) - CW

MANUFACTURING MATERIALS Casings Light alloy Gears Steel REDUCTION GEAR TRAIN

REAR CASING

REDUCTION GEARBOX For training purposes only © Copyright - TURBOMECA


ENGINE

Training Notes

ARRIUS 1

REDUCTION GEAR TRAIN - GENERAL Function

Main components

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

- Input gear - Double intermediate gear

Position

- Output gear

- In the lower part of the reduction gearbox.

- Casings.

Main characteristics - Type: 1 gear train with direct output parallel to the engine 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%).



ENGINE

ARRIUS 1

Training Notes

INPUT GEAR

POWER TURBINE SHAFT

DOUBLE INTERMEDIATE GEAR

Type 1 gear train with output parallel to the engine axis Input gear rotation speed 45438 RPM (100% N2) Output gear rotation speed 6016 RPM (100% N2)

OUTPUT GEAR

CASINGS

REDUCTION GEAR TRAIN - GENERAL For training purposes only © Copyright - TURBOMECA


ENGINE

Training Notes

ARRIUS 1

REDUCTION GEAR TRAIN - DESCRIPTION The reduction gear train includes three gears supported by ball and roller bearings.

Output gear

Input gear

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

The input gear is a simple helical gear directly mounted on the power turbine shaft by splines. It is supported by two roller bearings.

The output gear is supported by a roller bearing at the front and a ball bearing at the rear. A graphite seal ensures the sealing of the power drive.

Double intermediate gear The intermediate gear is a double gear. One gear is driven by 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 hydraulic torquemeter.



ENGINE

Training Notes INPUT GEAR

ARRIUS 1 INPUT GEAR

HYDRAULIC TORQUEMETER DOUBLE INTERMEDIATE GEAR

POWER DRIVE OUTPUT GEAR

GRAPHITE SEAL

REDUCTION GEAR TRAIN - DESCRIPTION For training purposes only © Copyright - TURBOMECA


ENGINE

Training Notes

ARRIUS 1

REDUCTION GEAR TRAIN - OPERATION The reduction gear train provides a forward output drive at a reduced speed to meet the drive requirements of the helicopter.

Operation of the torquemeter The engine torque measuring system is a hydraulic torquemeter housed in the double intermediate gear.

It also houses an engine torque measuring system.

Operation of the reduction gear train

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

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

Refer to chapter "MEASUREMENT AND INDICATING SYSTEMS" for the description and operation of the engine torque measuring system.

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



ENGINE

ARRIUS 1

Training Notes

POWER TURBINE

INPUT GEAR

INPUT GEAR 45438 RPM - 100% N2

DOUBLE INTERMEDIATE GEAR

OUTPUT GEAR 6016 RPM - 100% N2

Front face of the reduction gearbox

REDUCTION GEAR TRAIN - OPERATION For training purposes only © Copyright - TURBOMECA


ENGINE

Training Notes

ARRIUS 1

ACCESSORY DRIVE TRAIN - GENERAL Function Driven by the gas generator shaft, the accessory drive train provides the mechanical power required to drive the engine accessories.

Position - In the upper part of the reduction gearbox.

Main characteristics - Type: spur gear train - Drive gear rotation speed: 54117 RPM (100 % N1)

Main components - Accessory drive train - Casings.



ENGINE

Training Notes

ARRIUS 1 CASINGS

ACCESSORY DRIVE TRAIN Type Spur gear train Drive gear rotation speed 54117 RPM (100% N1)

ACCESSORY DRIVE TRAIN - GENERAL For training purposes only © Copyright - TURBOMECA


ENGINE

Training Notes

ARRIUS 1

ACCESSORY DRIVE TRAIN - DESCRIPTION The accessory drive train has 8 spur gears supported by ball bearings.

Intermediate gear (3) It is a double gear.

Drive gear

HP fuel pump gear

The drive gear is mounted on the gas generator shaft. It is a single gear. - Rotation speed: 54117 RPM (100% N1).

LP fuel pump and alternator gear It is a double gear.

Intermediate gear (1) It is a double gear.

Oil pump gear It is a single gear.

Intermediate gear (2) It is a single gear.

Starter-generator gear This gear also incorporates the centrifugal breather and the N1 phonic wheels. It is provided with a magnetic seal.



ENGINE

ARRIUS 1

Training Notes MAGNETIC SEAL

STARTER-GENERATOR GEAR (centrifugal breather, phonic wheels)

OIL PUMP GEAR

INTERMEDIATE GEAR (2) DRIVE GEAR INTERMEDIATE GEAR (3)

INTERMEDIATE GEAR (3)

LP FUEL PUMP AND ALTERNATOR GEAR DRIVE GEAR (54117 RPM)


INTERMEDIATE GEAR (1) HP FUEL PUMP GEAR

ACCESSORY DRIVE TRAIN - DESCRIPTION For training purposes only © Copyright - TURBOMECA


ENGINE

Training Notes

ARRIUS 1

ACCESSORY DRIVE TRAIN - OPERATION The accessory drive train drives the various accessories required for the engine operation.

Operation during starting During starting, the starter motor drives, through the accessory gear train, the gas generator rotating assembly.

Operation engine running The drive gear is directly driven by the gas generator shaft at a speed of 54117 RPM (100% N1). It drives the double intermediate gear which then drives:

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

- 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).



ENGINE

ARRIUS 1

Training Notes

STARTER-GENERATOR GEAR (centrifugal breather, phonic wheels)

STARTER-GENERATOR GEAR

OIL PUMP GEAR


GAS GENERATOR SHAFT

OIL PUMP GEAR


LP FUEL PUMP AND ALTERNATOR GEAR


LP FUEL PUMP AND ALTERNATOR GEAR

HP FUEL PUMP GEAR

DRIVE GEAR 54117 RPM (100% N1)

HP FUEL PUMP GEAR

Front face of the reduction gearbox

ACCESSORY DRIVE TRAIN - OPERATION For training purposes only © Copyright - TURBOMECA


ENGINE

ARRIUS 1

Training Notes

4 - OIL SYSTEM -

Oil system (79-00-00) ............................................ Oil reservoir .......................................................... Oil pumps (79-20-01) ............................................ Oil filter (79-20-02) ............................................... Pre-blockage pressure switch (79-00-00) ............. Cooling unit ............................................................ Centrifugal breather.............................................. Electrical magnetic plugs (79-30-01) .................... Strainers (79-30-02) ............................................... Low oil pressure switch (79-30-03) ....................... Oil pressure transmitter (79-30-04)...................... Oil temperature probe ........................................... Oil pipes (79-20-03) ................................................

4.2 4.8 4.10 4.14 4.20 4.22 4.24 4.26 4.28 4.30 4.32 4.34 4.36 to 4.37



OIL SYSTEM

Training Notes

ARRIUS 1

OIL SYSTEM - GENERAL Function

Lubrication requirements

The oil system ensures lubrication and cooling of the engine. It is also used for the hydraulic torquemeter operation.

Lubrication is required for the following components :

- Rear bearings

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

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

Sealing

Main characteristics - Type: variable pressure, full flow, dry sump system, synthetic oil - Max. oil temperature: 110°C (230°F)

- Front bearing

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

- 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).



OIL SYSTEM

ARRIUS 1

Training Notes GEARS AND BEARINGS OF THE ACCESSORY DRIVE TRAIN

OIL SYSTEM

ENGINE LUBRICATION

FRONT BEARING

REAR BEARINGS

ENGINE COOLING

TORQUEMETER

Type Variable pressure, full flow, dry sump, 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)

GEARS AND BEARINGS OF THE REDUCTION GEAR TRAIN

Max. oil pressure 1000 kPa (145 PSI)

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

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

OIL SYSTEM - GENERAL For training purposes only © Copyright - TURBOMECA


OIL SYSTEM

Training Notes

ARRIUS 1

OIL SYSTEM - DESCRIPTION The main components of the oil system are:

Cooling unit

Oil reservoir

The unit cools the lubricating oil by air circulation through an oil cooler. The oil cooler is provided with a by-pass valve.

The oil reservoir contains the volume of oil required to lubricate the engine. It is installed in the aircraft and is supplied by the aircraft manufacturer.

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

Centrifugal breather

Oil pump assembly The pump assembly includes one pressure pump and two scavenge pumps which ensure the oil circulation in the system.

The centrifugal breather separates the oil from the air-oil mist and vents the system. It is located in the accessory drive train, in the upper part of the gearbox casing.

The pumps are mechanically driven by the accessory drive train.

Indicating devices

The pressure pump is provided with a pressure relief valve.

- Filter pre-blockage pressure switch

The pumps are installed on the gearbox casing front face.

- Low oil pressure switch

Oil filter

- Oil pressure transmitter

The filter retains any particles which may be contained in the oil. The filter includes a by-pass valve and a preblockage pressure switch.

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

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

Strainers The strainers protect the scavenge pumps from debris in the system.


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


OIL SYSTEM

ARRIUS 1

Training Notes AIRCRAFT SYSTEM

ENGINE SYSTEM LOW OIL PRESSURE SWITCH

OIL FILTER

OIL PRESSURE TRANSMITTER

TORQUE TRANSMITTER

CENTRIFUGAL BREATHER

OIL RESERVOIR

MAGNETIC PLUG TEMPERATURE PROBE

COOLING UNIT (cooler provided with a by-pass valve)

PRESSURE PUMP (with pressure relief valve)

STRAINER

SCAVENGE PUMPS

ELECTRICAL MAGNETIC PLUGS

STRAINER

OIL SYSTEM - DESCRIPTION For training purposes only © Copyright - TURBOMECA


OIL SYSTEM

Training Notes

ARRIUS 1

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 the different engine sections which require lubrication. The pressure pump draws the oil from the reservoir and delivers it under pressure to the system. A pressure relief valve limits maximum pressure by returning oil to the pump 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 and reduction gear train

Scavenge After lubrication, the oil falls by gravity to the bottom of the sumps. The oil is then immediately drawn away by the scavenge pumps and returned to the reservoir through the cooling unit (dry sump system). Strainers protect the scavenge pumps against any particles which may be held in the lubrication oil.

Breathing The reservoir oil mist and the oil mist which results from lubrication are returned to the reduction gearbox where the oil is separated from the air by a centrifugal breather which vents the oil system to the exhaust through an external pipe.

- Gas generator front bearing

Indication of the oil system operation

- Gas generator rear bearing

The indication is ensured by the following components:

- Power turbine front bearing

- Low oil pressure switch

- Torquemeter.

- Oil pressure transmitter - Electrical magnetic plugs - Oil filter pre-blockage pressure switch - Aircraft components: level indicator, magnetic plug and temperature probe.



OIL SYSTEM

Training Notes

OIL SYSTEM INDICATING Level, pressure, temperature, magnetic particles, low pressure and filter pre-blockage

ARRIUS 1

SUPPLY SCAVENGE BREATHING AIR VENT

OIL SYSTEM - OPERATION For training purposes only © Copyright - TURBOMECA


OIL SYSTEM

Training Notes

ARRIUS 1

OIL RESERVOIR Function

Main components

The reservoir contains the volume of oil required for engine lubrication.

- Filler cap - Oil level sight glass (x 2)

Position

- Air vent union

- It is installed in the aircraft.

- Oil return union


- Oil supply union

- Aircraft manufacturer's supply

- Magnetic drain plug

- Oil system capacity: 4.8 litres (1.25 US G

- Temperature probe.

- Max. consumption: 0.3 l/h (0.08 US G/hr). Note: Refer to manufacturer's documentation for description and operation information.



OIL SYSTEM

ARRIUS 1

Training Notes

INTERFACES Aircraft/Engine OIL RESERVOIR

BREATHING (to centrifugal breather) OIL RETURN

OIL LEVEL SIGHT GLASS

FILLER CAP

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)

OIL SUPPLY

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

MAGNETIC DRAIN PLUG

TEMPERATURE PROBE

OIL RESERVOIR For training purposes only © Copyright - TURBOMECA


OIL SYSTEM

Training Notes

ARRIUS 1

OIL PUMPS - GENERAL - DESCRIPTION Function

Description

The pumps ensure oil circulation in the system.

They are driven at a speed proportional to N1.

Position

The pump assembly includes:

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

- The pump drive shaft

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

Main characteristics - Type: spur gear type

- 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 outlet unions

- Pressure relief valve setting: 1500 kPa (217.5 PSI). - The seal support plate - The pressure relief valve. O'ring seals ensure the sealing between the various pump bodies.

Note: The accessory drive train is provided with a coupling sleeve which is engaged on the oil pump assembly.



OIL SYSTEM

ARRIUS 1

Training Notes

Type Spur gear type Pressure relief valve setting 1500 kPa (217.5 PSI) PUMP DRIVE SHAFT

REAR BEARING SCAVENGE PUMP

PRESSURE PUMP

OIL PUMPS

SEAL SUPPORT PLATE

FRONT BEARING SCAVENGE PUMP

DRIVEN SHAFT

OIL PUMPS - GENERAL - DESCRIPTION For training purposes only © Copyright - TURBOMECA


OIL SYSTEM

Training Notes

ARRIUS 1

OIL PUMPS - OPERATION Principle of operation of a spur gear type pump

Scavenge pump operation

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

Two scavenge pumps, one for the reduction gearbox and front bearings, and one for the rear bearings, return the oil to the reservoir. The scavenge pump flow is higher than the pressure pump flow (dry sump system).

Pressure pump operation The pressure pump draws the oil from the reservoir and delivers it under pressure to the supply system. The full pressure pump flow is used (full flow, oil pressure as 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 pressure pump outlet. The valve returns the excess oil to the pressure pump inlet when the pressure is higher than the valve setting. In normal operation, the pressure relief valve is closed.



OIL SYSTEM

ARRIUS 1

Training Notes OIL INLET (from reservoir)

OIL OUTLET (to filter)

SCAVENGE (reduction gearbox and front bearings) Normal operation (valve closed)

OIL OUTLET (to cooling unit)

SCAVENGE (rear bearings)

DRIVE GEAR

Overpressure (valve open)

Oil inlet

OPERATION OF THE PRESSURE RELIEF VALVE

Oil outlet

DRIVEN GEAR

PRINCIPLE OF OPERATION OF A SPUR GEAR TYPE PUMP

OIL PUMPS - OPERATION For training purposes only © Copyright - TURBOMECA


OIL SYSTEM

Training Notes

ARRIUS 1

OIL FILTER - GENERAL Function

Main components

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

- Pre-blockage pressure switch

Position

- By-pass valve - Filtering element

- In the system: downstream of the pressure pump - On the engine: the oil filter is installed beside the fuel filter inside the filter assembly which is mounted at the upper part of the gearbox casing.

- Filter bowl - Filter casing.

Main characteristics - 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).



OIL SYSTEM

Training Notes

ARRIUS 1

PRE-BLOCKAGE PRESSURE SWITCH

BY-PASS VALVE

FILTERING ELEMENT

Type Metal cartridge (or fiberglass)

FILTER BOWL

Filtering ability 20 microns Pre-blockage pressure switch ∆P 120 kPa (18 PSID) By-pass valve ∆P 220 kPa (32 PSID)

FILTER CASING

OIL FILTER - GENERAL For training purposes only © Copyright - TURBOMECA


OIL SYSTEM

Training Notes

ARRIUS 1

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 its support. The oil which remains in the filter then flows to the gearbox sump through the drain orifice.



OIL SYSTEM

ARRIUS 1

Training Notes PRE-BLOCKAGE PRESSURE SWITCH

HEAT EXCHANGER WALL

BY-PASS VALVE

Fuel filter

FILTERING ELEMENT FILTER BOWL Oil inlet BASE Fuel inlet Oil outlet

DRAIN VALVE To the reduction gearbox

FILTER DRAIN

OIL FILTER - DESCRIPTION For training purposes only © Copyright - TURBOMECA


OIL SYSTEM

Training Notes

ARRIUS 1

OIL FILTER - OPERATION Normal operation

Blockage (by-pass operation)

In normal operation, the oil delivered by the pressure pump enters the filtering unit through an orifice located in the filter base.

When the pressure difference on the by-pass valve is higher than by-pass valve setting, the valve opens and allows the supply of unfiltered oil to the engine.

The oil flows between the fuel filter wall and the heat exchanger wall (oil cooling by fuel heating). The oil enters the oil filter through an orifice located between the two chambers and then flows through the filtering element. The filtered oil then flows to the different engine sections which require lubrication.

Pre-blockage When the filtering element becomes dirty, the pressure difference on the by-pass valve increases. For a pressure difference higher than the pre-blockage switch setting, the by-pass valve moves slightly to release the switch which provides indication in the cockpit. The pre-blockage switch is automatically rearmed as the pressure difference decreases (normally at engine shutdown).



OIL SYSTEM

ARRIUS 1

Training Notes FILTERING ELEMENT OPERATION (filter clean)

NORMAL OPERATION PRE-BLOCKAGE PRESSURE SWITCH


INDICATION

INDICATION

SLIGHT BLOCKAGE OF THE FILTERING ELEMENT

BY-PASS VALVE OPENING

PRE-BLOCKAGE

BLOCKAGE OF THE FILTERING ELEMENT BLOCKAGE

OIL FILTER - OPERATION For training purposes only © Copyright - TURBOMECA


OIL SYSTEM

Training Notes

ARRIUS 1

PRE-BLOCKAGE PRESSURE SWITCH Function

Functional description

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

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

Position

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

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

Main characteristics - Type: with plunger - Setting: ∆P 120 kPa (18 PSID) - Cockpit indication.

The switch thermal lock is released for an increasing temperature of + 50°C (122°F) and actuated for a decreasing temperature of + 30°C (86°F). When the filtering element becomes dirty, the valve doesn’t open but moves down slightly and reduces the magnetic field between the magnetic rod and the plunger. Then the released plunger closes the electrical circuit and the indication is given in the cockpit. The indication is cancelled if the differential pressure becomes lower than ∆P 100 kPa (14.5 PSID) (automatic reset).



OIL SYSTEM

ARRIUS 1

Training Notes ELECTRICAL CONNECTOR

MICROSWITCH

PLUNGER

THERMAL LOCK ( +50°C / 122°F) ( +30°C / 86°F) MAGNETIC ROD Oil inlet


BY-PASS VALVE

SPRING

FILTERING UNIT

FILTERING ELEMENT

Oil outlet

Type With plunger Setting ∆P 120 kPa (18 PSID) Cockpit indication

PRE-BLOCKAGE PRESSURE SWITCH For training purposes only © Copyright - TURBOMECA


OIL SYSTEM

Training Notes

ARRIUS 1

COOLING UNIT Function

Description

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

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

Position

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

- In the system: between the scavenge pumps and the oil reservoir - The cooling unit is installed in the aircraft.

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

Main characteristics - Aircraft manufacturer's supply - Type: air-oil cooler - By-pass and thermostatic valve: • Fully open: < 96°C (205°F) • Fully closed: > 106°C (223°F).



OIL SYSTEM

ARRIUS 1

Training Notes

OIL COOLER

INTERFACES Aircraft/Engine

COOLING UNIT

Aircraft manufacturer's supply Type Air-oil cooler By-pass and thermostatic valve Fully open: < 96°C (205°F) Fully closed: > 106°C (223°F)

OIL COOLER

AIR

COOLING FAN

To reservoir Cooling air outlet

From scavenge pumps

BY-PASS AND THERMOSTATIC VALVE

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

COOLING UNIT For training purposes only © Copyright - TURBOMECA


OIL SYSTEM

Training Notes

ARRIUS 1

CENTRIFUGAL BREATHER General

Operation

Function

The centrifugal breather is driven by the intermediate gear.

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

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

Position

- Centrifugal force throws the oil droplets out into the reduction gearbox

- On the engine: formed by the starter-generator drive gear.

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

Main characteristics - 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-generator drive gear. The gear is supported by two ball bearings. Graphite seals ensure the sealing of the ball bearings.



OIL SYSTEM

ARRIUS 1

Training Notes

AIR-OIL MIST (from reservoir) AIR VENT (to the exhaust pipe through an external pipe)

DE-OILED AIR REDUCTION GEARBOX CASING

GRAPHITE SEAL

GRAPHITE SEAL

Type Centrifugal Air vent Through the rear part of the hollow shaft, connected to the exhaust

INTERMEDIATE GEAR (accessory drive train)

OIL DROPLETS

BREATHER (starter-generator drive gear)

CENTRIFUGAL BREATHER For training purposes only © Copyright - TURBOMECA


OIL SYSTEM

Training Notes

ARRIUS 1

ELECTRICAL MAGNETIC PLUGS Function

Main components

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

- Magnetic plug body - Magnetic probe

Position

- Electrical connector (connection with the cockpit)

- In the system: 2 electrical magnetic plugs upstream of the 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.

Main characteristics - Type: magnetic probe - Quantity: 2 in parallel - Cockpit indication.

- 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 which attract magnetic particles in the scavenge return lines: - Of the front part (reduction gearbox and gas generator front bearing) - Of the rear part (gas generator rear bearing and power turbine bearings). When particles bridge the gap between the magnetic poles, it provides cockpit indication.



OIL SYSTEM

ARRIUS 1

Training Notes

ELECTRICAL CONNECTOR (connection with the cockpit)

LOCKING SLOT

MOUNTING PIN

ELECTRICAL MAGNETIC PLUG

+

MAGNETIC PROBE

INDICATION

STRAINER

Type Magnetic probe

BRIDGE OF PARTICLES

Quantity 2 in parallel Cockpit indication

OPERATION WITH PARTICLES

ELECTRICAL MAGNETIC PLUGS For training purposes only © Copyright - TURBOMECA


OIL SYSTEM

Training Notes

ARRIUS 1

STRAINERS Function


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

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

Position - In the system: 1 strainer upstream of each scavenge pump

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

- On the engine: 1 strainer at the front lower part of the reduction gearbox and 1 underneath the combustion chamber casing.

Main characteristics - Type: wide mesh filter and electrical magnetic plug receptacle - Quantity: 2



OIL SYSTEM

ARRIUS 1

Training Notes

STRAINER

ELECTRICAL MAGNETIC PLUG RECEPTACLE

Type Wide mesh filter and electrical magnetic plug receptacle WIDE MESH FILTER

Quantity 2

STRAINERS For training purposes only © Copyright - TURBOMECA


OIL SYSTEM

Training Notes

ARRIUS 1

LOW OIL PRESSURE SWITCH Function

Main components

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

- Pressure switch body - Electrical connector (connection with the cockpit).

Position - In the system: downstream of the filter, in the oil supply system

Operation Normal operation

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

Main characteristics - Type: Diaphragm pressure switch - Setting: • Decreasing pressure: 170 kPa (25 PSI) • Increasing pressure: 200 kPa (29 PSI) - Cockpit indication.


Increasing pressure: when the oil pressure is higher than the low oil pressure switch setting, the diaphragm lifts the plunger which acts on the microswitch and thus opens the electrical circuit. “Low pressure” operation Decreasing pressure: when the oil pressure is lower than the setting, the diaphragm drops, and the plunger releases the microswitch and thus closes the electrical circuit and provides the low oil pressure indication in the cockpit.


OIL SYSTEM

Training Notes

ARRIUS 1

Type Diaphragm pressure switch Setting Decreasing pressure 170 kPa (25 PSI) Increasing pressure 200 kPa (29 PSI) Cockpit indication

LOW OIL PRESSURE SWITCH

ELECTRICAL CONNECTOR (to the cockpit)

LOW OIL PRESSURE SWITCH For training purposes only © Copyright - TURBOMECA


OIL SYSTEM

Training Notes

ARRIUS 1

OIL PRESSURE TRANSMITTER Function

Main components

This transmitter provides signals of oil pressure to the cockpit.

- Transmitter body

Position

- Electrical connector (connection with the cockpit).

Operation

- In the system: downstream of the filter, in the oil supply system - On the engine: on a mounting pad located on the gearbox casing front face.


It has a resistor bridge printed on a flexible support. This flexible support is subjected to the oil pressure and the resistor bridge is supplied electrically from the indicating system. Changes in oil pressure cause movement of the flexible support which changes the resistance and thus the output voltage.

- Type: resistive - Output signals: electrical voltage proportional to the oil pressure - Cockpit indication.



OIL SYSTEM

ARRIUS 1

Training Notes


ELECTRICAL CONNECTOR (connection with the cockpit)

Type Resistive Output signal Electrical voltage proportional to the oil pressure


Cockpit indication

OIL PRESSURE TRANSMITTER For training purposes only © Copyright - TURBOMECA


OIL SYSTEM

Training Notes

ARRIUS 1

OIL TEMPERATURE PROBE General


Function

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

The oil temperature probe measures the oil temperature at the oil reservoir outlet and provides indication to the cockpit. Position - In the oil system: the probe is located downstream of the oil reservoir. Main characteristics - Aircraft manufacturer's supply - 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 oil temperature - Cockpit indication.



OIL SYSTEM

ARRIUS 1

Training Notes

INTERFACES Aircraft/Engine

OIL TEMPERATURE PROBE

NICKEL RESISTOR

CONTROL PANEL (to oil temperature indicator)

1 2 3

CONSTANT I (mA)

Aircraft manufacturer's supply Type Nickel resistor VARIABLE OUTPUT VOLTAGE

Resistance value 100 Ω at 0°C (32°F) 165 Ω at 100°C (212°F) Output signal Electrical voltage proportional to the oil temperature Cockpit indication

OIL TEMPERATURE PROBE For training purposes only © Copyright - TURBOMECA


OIL SYSTEM

Training Notes

ARRIUS 1

OIL PIPES This part deals with the external pipes and internal ducts of the oil system.

Internal ducts Supply

External pipes Supply - From reservoir to pressure pump - From air intake casing to rear bearings. Scavenge

- 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.

- From rear bearings to strainer support box Scavenge - From strainer support box to air intake casing - From reduction gearbox to scavenge pump. - From scavenge pumps to oil cooler - From oil cooler to reservoir. Breathing - From reservoir to reduction gearbox - From reduction gearbox to exhaust pipe.



OIL SYSTEM

ARRIUS 1

Training Notes SUPPLY (rear bearings)

AIR VENT (from reduction gearbox to exhaust pipe)

SCAVENGE (rear bearings)

SUPPORT BOX (strainer and electrical magnetic plug)

LEFT SIDE VIEW

AIR VENT (from reduction gearbox to exhaust pipe)

AIR VENT UNION (from reservoir) OIL INLET UNION (from reservoir)

OIL OUTLET UNION (to oil cooler)

TOP VIEW

OIL PIPES For training purposes only © Copyright - TURBOMECA


OIL SYSTEM

Training Notes

ARRIUS 1

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



AIR SYSTEM

Training Notes

ARRIUS 1

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, main characteristics, description and operation.



AIR SYSTEM

ARRIUS 1

Training Notes

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

AIR SYSTEM For training purposes only © Copyright - TURBOMECA


AIR SYSTEM

Training Notes

ARRIUS 1

INTERNAL AIR SYSTEM Function

- The front face of the gas generator turbine disc

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

- 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

Pressurisation of labyrinth seals

- The front face of the power turbine disc.

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

Balance of forces on rotating assemblies

- 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 shaft and the turbine disc and goes out through holes in the rear of the turbine disc to pressurise the rear bearing labyrinths.

Some of the diffuser outlet air applies a compensation pressure on the balance piston located at the front of the gas generator turbine through a labyrinth.

Cooling of internal parts The air from the outlet of the compressor diffuser, cools the following components: - The combustion chamber walls - The turbine nozzle guide vanes



AIR SYSTEM

Training Notes

ARRIUS 1 GAS GENERATOR REAR BEARING LABYRINTH SEAL

POWER TURBINE BEARING LABYRINTH SEAL

AIR TAPPED FROM THE TIP OF THE COMPRESSOR WHEEL

BALANCE PISTON

LABYRINTH SEAL OF THE GAS GENERATOR FRONT BEARING

P2.5 - AIR TAPPED FROM THE MIDDLE OF THE COMPRESSOR WHEEL AIR TAPPED FROM THE TIP OF THE COMPRESSOR WHEEL P3 - AIR TAPPED FROM THE OUTLET OF THE COMPRESSOR DIFFUSER

INTERNAL AIR SYSTEM For training purposes only © Copyright - TURBOMECA


AIR SYSTEM

Training Notes

ARRIUS 1

AIR TAPPINGS Function

Air pressure signal for the control system

The air tappings are used for:

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

- Start injector ventilation P3 air is tapped through a calibrated restrictor; and is taken by an external pipe to a pressure sensor, to provide a P3 signal to the Digital Control Unit.

- The control system (pressure signal) - Aircraft services.

Start injector ventilation An air bleed (located on the engine right side) bleeds compressor delivery pressure air. This air supplies, through an external pipe, the start electro-valve for start injector ventilation. Ventilation of the start injectors purges fuel from them at the end of starting and prevents carbonisation.


Note: The engine has also a temperature probe installed on the plenum lower part (refer to following pages for more details).

Aircraft services The engine has an air bleed on each side of the combustion chamber casing. The air, tapped from the compressor outlet, can be used by the aircraft systems for various purposes (refer to following pages for more details).


AIR SYSTEM

ARRIUS 1

Training Notes

DIGITAL CONTROL UNIT

AIRCRAFT SERVICES

P3 PRESSURE SIGNAL TO THE CONTROL SYSTEM

AIR PRESSURE SENSOR

START ELECTRO-VALVE

P3 air VENTILATION OF START INJECTORS

START INJECTORS

AIR TAPPINGS For training purposes only © Copyright - TURBOMECA


AIR SYSTEM

Training Notes

ARRIUS 1

AIR TAPPING UNIONS Function


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

- Quantity: 4 - Air pressure: 860 kPa (125 PSI)

Position

- Air temperature: 320°C (608°F).

Aircraft air tappings


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

The air tappings have unions which are provided with restrictors to limit flow in order to prevent loss of engine power in the event of a broken pipe.

Start injector ventilation tapping The air tapping not in use is provided with a blank. The air tapping for the ventilation of the start injectors is installed on the right upper part of the combustion chamber casing.

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

Air pressure sensor tapping The tapping for the pressure sensor is installed on the left upper part of the combustion chamber casing.



AIR SYSTEM

ARRIUS 1

Training Notes

START INJECTOR VENTILATION TAPPING

PRESSURE SENSOR TAPPING

AIRCRAFT AIR TAPPING UNION RESTRICTOR

Quantity 4 Pressure 860 kPa (125 PSI) Temperature 320°C (608°F)

UNION

AIR TAPPING UNIONS For training purposes only © Copyright - TURBOMECA


AIR SYSTEM

Training Notes

ARRIUS 1

AIR PRESSURE SENSOR Function

Main components

The sensor measures the air pressure at the centrifugal compressor outlet and provides a pressure signal to the Digital Control Unit.

- Air pressure sensor

Position

- Air tapping.

- The sensor is secured on the upper part of the gearbox casing. It is connected to an air tapping located on the left side of the combustion chamber casing by means of an external pipe.



The air pressure sensor is of resistive type. It has a resistor bridge printed on a flexible support subjected to P3 air pressure. The support deformations, according to the air pressure, create an output voltage proportional to the pressure, for a constant input voltage.

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


- Pipe

The output voltage is used by the Digital Control Unit.


AIR SYSTEM

ARRIUS 1

Training Notes AIR PRESSURE SENSOR

PIPE

AIR TAPPING

PRESSURE SENSOR

1 TO DIGITAL CONTROL UNIT

Type Resistive

-

3 2

Ve

Vs

+

Output signal Voltage proportional to the P3 air pressure

4 5

+

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

AIR PRESSURE SENSOR For training purposes only © Copyright - TURBOMECA


AIR SYSTEM

Training Notes

ARRIUS 1

AIR TEMPERATURE PROBE Function

Main components

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

- Electrical connector (connection with the DCU) - Mounting flange

Position

- Seal

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

- Probe.



- Probe supplied by the engine manufacturer but installed on the air intake volute which is supplied by the aircraft manufacturer

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

- Type: platinum resistor

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

- Resistor value: 100 Ω at 0°C (32°F) - Output signal: voltage proportional to the ambient air temperature.



AIR SYSTEM

ARRIUS 1

Training Notes

ELECTRICAL CONNECTOR (to DCU)

Type Platinum resistor

MOUNTING FLANGE

Resistor value 100 Ω at 0°C (32°F) SEAL

Output signal Voltage proportional to the ambient air temperature

Resistor DIGITAL CONTROL UNIT

PROBE

Voltage Constant I (mA)

AIR TEMPERATURE PROBE For training purposes only © Copyright - TURBOMECA


AIR SYSTEM

ARRIUS 1

Training Notes

6 - FUEL SYSTEM -

Fuel system (73-00-00) .......................................... Fuel pressure transmitter (73-30-02) ................... LP fuel pump - Alternator unit (73-10-01) ......... Fuel filter (73-10-02) .............................................. Pre-blockage pressure switch (73-30-01) ............. HP fuel pump and metering unit (73-10-03)........ Stop electro-valve (73-10-04) ................................ Fuel valve assembly (73-10-05) ............................ Start injectors (73-10-06) ..................................... Main injectors (73-10-07) ...................................... Combustion chamber drain valve (73-10-08) ........ Fuel pipes (73-10-09).............................................

6.2 6.16 6.18 6.24 6.30 6.32 6.38 6.42 6.48 6.54 6.60 6.62 to 6.63



FUEL SYSTEM

Training Notes

ARRIUS 1

FUEL SYSTEM - GENERAL Function

Main components

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

- Low Pressure unit (pump and alternator) - Fuel filter

Position

- High Pressure unit (pump and metering unit)

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

- Valve assembly

The Digital Control Unit is installed in the aircraft cargo compartment.

- Sensors and input signals.

- Injection system

Main characteristics - 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.



FUEL SYSTEM

ARRIUS 1

Training Notes

SENSORS AND INPUT SIGNALS


HIGH PRESSURE UNIT (pump and metering unit)

P3

MANUAL CONTROL FUEL FILTER

FUEL RESERVOIR

FUEL VALVE ASSEMBLY

INJECTION SYTEM

LOW PRESSURE UNIT (pump and alternator) Aircraft

Engine

FUEL SYSTEM - GENERAL For training purposes only © Copyright - TURBOMECA


FUEL SYSTEM

Training Notes

ARRIUS 1

FUEL SYSTEM - DESCRIPTION The fuel system includes the following components:

Valve assembly

Booster pump (low pressure aircraft system).

The assembly includes: - A 3 way start electro-valve

Low pressure pump unit - A pressurising valve This unit includes a centrifugal low pressure pump and an alternator to electrically supply the Digital Control Unit.

- A flow divider

Filtering unit

- A manual purge device.

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

Start injectors: 4 injectors fitted around the combustion chamber casing. Main injectors: 10 pre-vaporising injectors installed at the rear of the combustion chamber.

High pressure pump unit - Metering unit This unit includes a gear type high pressure pump fitted with a pressure relief valve.

Fuel pressure transmitter

It also has a metering unit which includes:

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

- A constant ∆P valve

Fuel flow transmitter

- A manual metering valve

This is optional on the 1A and 1E and is standard on the 1M. It is fitted in the delivery line between the metering unit and the valve assembly.

- A fuel metering valve (controlled by the DCU) - A bi-stable stop electro-valve.



FUEL SYSTEM

ARRIUS 1

Training Notes HIGH PRESSURE PUMP AND METERING UNIT Constant ∆P valve

High Pressure Pressure relief valve pump

Manual control

Metering Flowmeter Manual purge (optional) device valve

Pressurising Flow valve divider

FILTERING UNIT Filtering element By-pass valve

MAIN INJECTORS FUEL VALVE ASSEMBLY

Pre-blockage pressure switch Blockage indicator

Start electro-valve Alternator

LOW PRESSURE PUMP UNIT

Low pressure pump FUEL PRESSURE TRANSMITTER

BOOSTER PUMP (aircraft system)

Stop electro-valve

START INJECTORS

FUEL SYSTEM - DESCRIPTION For training purposes only © Copyright - TURBOMECA


FUEL SYSTEM

Training Notes

ARRIUS 1

FUEL SYSTEM - OPERATION (1) This part deals with the following operating phases: prestart, starting, normal operation, manual control and shutdown.

Pre-start - The LP and HP pumps are not operating and there is no pressure 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 is initialised (refer to "CONTROL SYSTEM" chapter) and the "stop" coil of the stop electro-valve is electrically supplied.



FUEL SYSTEM

ARRIUS 1

Training Notes

HP PUMP (stopped)

MANUAL CONTROL (neutral position)

METERING PRESSURISING VALVE VALVE (any position) (closed)

FLOW DIVIDER (closed)

CONSTANT ∆P VALVE (closed)

START ELECTRO-VALVE (in ventilation position)

LP PUMP (stopped)

STOP ELECTRO-VALVE (stop position) PRE-START

FUEL SYSTEM - OPERATION (1) For training purposes only © Copyright - TURBOMECA


FUEL SYSTEM

Training Notes

ARRIUS 1

FUEL SYSTEM - OPERATION (2) Starting The engine start command causes the pump to rotate and the fuel is first supplied to the start injectors and then to the main injectors. The constant ∆P valve operates and the fuel flow is metered by the metering unit controlled by the Digital Control Unit according to given laws (refer to the “CONTROL SYSTEM” chapter). At the end of starting, the start components are de-energised and the start injectors are ventilated. The speed is stabilised at a controlled value.



FUEL SYSTEM

ARRIUS 1

Training Notes LP PRESSURE HP PRESSURE

HP PUMP (driven)

METERING VALVE (in control)

PRESSURISING VALVE (open)

FLOW DIVIDER (open)

METERED FUEL

CONSTANT ∆P VALVE (in control)

MAIN INJECTORS (supplied)

START ELECTRO-VALVE (open) LP PUMP (driven)

BOSTER PUMP (in operation)

STOP ELECTRO-VALVE (running position)

START INJECTORS (supplied)

STARTING



FUEL SYSTEM

Training Notes

ARRIUS 1

FUEL SYSTEM - OPERATION (3) Normal running The required fuel flow is metered by the metering unit. The metering unit position is determined by the Digital Control Unit (refer to the “CONTROL SYSTEM” chapter). The high pressure pump (HP) always supplies more fuel than the engine requires. The excess fuel returns to the HP pump inlet through the constant ∆P valve. The start injectors are continuously ventilated by air tapped from the combustion chamber casing.



FUEL SYSTEM

ARRIUS 1

Training Notes HP PUMP (driven)

METERING VALVE (in control)

PRESSURISING VALVE (open)

FLOW DIVIDER (open)

MAIN INJECTORS (supplied)

CONSTANT ∆P VALVE (in control)

P3 air

START ELECTRO-VALVE (in ventilation) LP PUMP (driven)

START INJECTORS (ventilated) NORMAL RUNNING



FUEL SYSTEM

Training Notes

ARRIUS 1

FUEL SYSTEM - OPERATION (4) Manual control In case of a fuel system failure, the fuel flow can be manually controlled by actuating the manual metering valve in the "+" range (flow increase) or "-" range (flow decrease). In the "+" range, the fuel by-passes the main valve and is added to the main valve flow. In the "-" range, the flow is directly limited by the manual metering valve.



FUEL SYSTEM

ARRIUS 1

Training Notes

N

N

N

Q

Q=0

NORMAL (N)

Q

Q

MANUAL +

Q≠0

Q=0

MANUAL -

MANUAL CONTROL



FUEL SYSTEM

Training Notes

ARRIUS 1

FUEL SYSTEM - OPERATION (5) Shut-down The stop command opens the stop electro-valve which reduces the fuel pressure downstream of the constant ∆P valve which opens fully. The fuel then returns to the HP pump inlet; the flow to the injectors is shut-off and the engine stops.



FUEL SYSTEM

Training Notes

ARRIUS 1

CONSTANT ∆P VALVE (open)

STOP ELECTRO-VALVE (stop position)

SHUT-DOWN



FUEL SYSTEM

Training Notes

ARRIUS 1

FUEL PRESSURE TRANSMITTER Function

Main components

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

- Fuel pressure transmitter - Support

Position

- Fuel pipe

- In the system: upstream of the LP pump - On the engine: secured by a clamp on a support located on the upper left side of the gearbox.


- Electrical harness. Note: A optional fuel flow transmitter can be supplied as optional equipment.

- Type: resistive


- Output signals: electrical voltage proportional to the fuel pressure

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

- Cockpit indication.

This flexible support is subjected to the fuel pressure and the resistor bridge is supplied electrically from the indicating system. Changes in fuel pressure cause movement of the flexible support which changes the resistance and thus the output voltage. The transmitter is subjected to the fuel pressure delivered through a flexible pipe which is connected to the LP pump/ alternator union.



FUEL SYSTEM

ARRIUS 1

Training Notes

ELECTRICAL CONNECTOR

Type Resistive Output signal Electrical voltage proportional to the fuel pressure Cockpit indication FUEL PRESSURE TRANSMITTER FUEL PIPE

SUPPORT ELECTRICAL HARNESS

PRESSURE TRANSMITTER

1

-

3 CONTROL PANEL

2

Ve

Vs

+

4 5

FUEL FLOW TRANSMITTER (optional)

+

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

FUEL PRESSURE TRANSMITTER For training purposes only © Copyright - TURBOMECA


FUEL SYSTEM

Training Notes

ARRIUS 1

LP FUEL PUMP - ALTERNATOR UNIT GENERAL Function

Main components

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

- LP pump

Position

The following components can also be mentioned:

- On the front of the gearbox casing.

- Fuel inlet union (from aircraft system)


- Union and pipe of the pressure transmitter

LP pump - Type: centrifugal with ejector

- Alternator.

- Drain union - Alternator electrical connector.

- Rotation speed: 24052 RPM (100% N1). Alternator - Nominal power: 100 V.A. - Operation: continuous - Output voltage: 28 to 63 Volts.



FUEL SYSTEM

ARRIUS 1

Training Notes

PRESSURE TRANSMITTER PIPE

ALTERNATOR CONNECTOR (to Digital Control Unit)

ALTERNATOR

LP PUMP Type Centrifugal with ejector Rotation speed 24052 RPM (100% N1) ALTERNATOR Nominal power 100 V.A.

FUEL INLET UNION (from aircraft low pressure system)

Operation Continuous LP PUMP

Output voltage 28 to 63 Volts

DRAIN UNION

Return from stop electro-valve

LP FUEL PUMP - ALTERNATOR UNIT - GENERAL For training purposes only © Copyright - TURBOMECA


FUEL SYSTEM

Training Notes

ARRIUS 1

LP FUEL PUMP - ALTERNATOR UNIT DESCRIPTION LP pump unit

Alternator

The LP pump includes the following components :

The alternator includes:

- The fuel inlet union and the return from the stop electrovalve

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

- The ejector jet which improves the LP pump fuel flow by venturi effect - The LP pump rotor

- A stator housed in the alternator body and supported by two ball bearings (lubricated by oil mist). Two delivery and return orifices are located on the support - The sealing between the different elements is ensured by O’ring seals.

- The pump and alternator drive shaft. The shaft is supported 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 passes into the gearbox. A drain between the seals drains any leaks overboard.

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



FUEL SYSTEM

ARRIUS 1

Training Notes

BALL BEARING

ALTERNATOR (rotor and stator)

BALL BEARING

EJECTOR JET Fuel outlet (to filter) Fuel inlet union (and return from stop electro-valve)

LP PUMP ROTOR Fuel return (from constant ∆P valve) DRAIN SEALING RINGS

LP PUMP DRIVE SHAFT

LP FUEL PUMP - ALTERNATOR UNIT - DECRIPTION For training purposes only © Copyright - TURBOMECA


FUEL SYSTEM

Training Notes

ARRIUS 1

LP FUEL PUMP - ALTERNATOR UNIT OPERATION LP pump unit The fuel supplied by the aircraft system enters the helical inducer which draws the fuel into the impeller. The impeller pumps the fuel to the outlet. A given quantity of fuel is returned to the ejector to increase the inlet pressure of the LP pump. An internal duct takes the fuel from the constant ∆P valve to the fuel outlet. On engine shut-down, the fuel from the stop electro-valve returns to the LP pump inlet.



FUEL SYSTEM

ARRIUS 1

Training Notes

To filter

ALTERNATOR

LP PUMP

From stop electro-valve

Aircraft FUEL PRESSURE TRANSMITTER

BOOSTER PUMP

LP FUEL PUMP - ALTERNATOR UNIT - OPERATION For training purposes only © Copyright - TURBOMECA


FUEL SYSTEM

Training Notes

ARRIUS 1

FUEL FILTER - GENERAL Function

Main components

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

- Filtering element - Pre-blockage pressure switch

Position

- Blockage indicator (red visual indicator and transparent cover)

- In the system: at the LP pump outlet - On the engine: it is installed beside the oil filter inside the filter assembly located at the upper part of the gearbox casing.

- By-pass valve - Drain valve and drain union - Filter bowl


- Filter 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).



FUEL SYSTEM

ARRIUS 1

Training Notes

BLOCKAGE INDICATOR

BY-PASS VALVE

FILTERING ELEMENT

FILTER BOWL

Type Metal cartridge (or fiberglass) Filtering ability 20 microns

FILTER CASING

Pre-blockage pressure switch ∆P 120 kPa (17.4 PSID) By-pass valve ∆P 220 kPa (32 PSID) DRAIN UNION (fitted with a blank)

MOUNTING OF THE PRE-BLOCKAGE SWITCH

FUEL FILTER - GENERAL For training purposes only © Copyright - TURBOMECA


FUEL SYSTEM

Training Notes

ARRIUS 1

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 transparent cover) - 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 its support. The fuel which remains in the filter then flows through the drain orifice.



FUEL SYSTEM

ARRIUS 1

Training Notes HEAT EXCHANGER WALL

BLOCKAGE INDICATOR

BY-PASS VALVE

FILTERING ELEMENT FILTER BOWL

Oil filter

FILTER CASING Oil inlet

Fuel inlet Fuel outlet

DRAIN VALVE To drain system

FILTER DRAIN

FUEL FILTER - DESCRIPTION For training purposes only © Copyright - TURBOMECA


FUEL SYSTEM

Training Notes

ARRIUS 1

FUEL FILTER - OPERATION The operation is considered in normal operation, preblockage and blockage.

Normal operation In normal operation, the fuel delivered by the LP pump enters the filtering unit through an orifice located in the filter base.

Blockage When the pressure difference on the by-pass valve exceeds the setting, the spring loaded mechanical indicator pops out. The fuel then by-passes the filtering element and flows to the HP pump.

The fuel flows inside the heat exchanger (oil cooling and fuel heating). The fuel enters the fuel filter and flows through the filtering element. The filtering element retains particles larger than 20 microns. The fuel then flows to the HP pump.

Pre-blockage When the filter becomes dirty, the pressure difference across the filtering element increases. If the pressure difference becomes higher than the pre-blockage pressure switch setting, the electrical contact of the pressure switch closes and gives a cockpit indication.



FUEL SYSTEM

ARRIUS 1

Training Notes PRE-BLOCKAGE PRESSURE SWITCH OPERATION

ONSET OF FILTER BLOCKAGE

COCKPIT INDICATOR

FILTERING ELEMENT OPERATION (20 microns)

PRE-BLOCKAGE

OPENING OF BY-PASS VALVE

CLOGGED FILTER

OPERATION OF THE BLOCKAGE INDICATOR NORMAL OPERATION

BLOCKAGE

FUEL FILTER - OPERATION For training purposes only © Copyright - TURBOMECA


FUEL SYSTEM

Training Notes

ARRIUS 1

PRE-BLOCKAGE PRESSURE SWITCH General

Functional descripion

Function

Normal operation

The pressure switch provides a cockpit indication of fuel filter pre-blockage. Position

The filtering element is clean. The pressure difference on each side of the filter is lower than the pre-blockage pressure switch setting: the electrical contact is open and there is no indication in the cockpit.

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

Filter pre-blockage


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

- Type: with microswitch - Pre-adjusted setting: ∆P 120 kPa (17.4 PSID) - Cockpit indication.


When the pressure difference exceeds the pressure switch setting, the electrical switch closes and illuminates in the cockpit. The indication stops as soon as the differential pressure becomes lower than ∆P 60 kPa (8.7 PSID) (automatic reset of the pre-blockage switch).


FUEL SYSTEM

ARRIUS 1

Training Notes FILTERING UNIT



Microswitch closed Type With microswitch Pre-adjusted setting ∆P 120 kPa (17.4 PSID)

COCKPIT (indicator)

Cockpit indication

FILTER PRE-BLOCKAGE

PRE-BLOCKAGE PRESSURE SWITCH For training purposes only © Copyright - TURBOMECA


FUEL SYSTEM

Training Notes

ARRIUS 1

HP FUEL PUMP AND METERING UNIT GENERAL Function

Main components

The HP fuel pump and metering unit supplies fuel under pressure to the fuel system and meters the fuel flow according to the power required. A pressure relief valve relieves the excess fuel pressure to the pump inlet.

The HP fuel pump and metering unit includes:

Position

- An HP fuel pump unit and a pressure relief valve - A metering unit (main metering valve, constant ∆P valve, manual metering lever).

- In the system: downstream of the filtering unit. - On the engine: the HP fuel pump and metering unit is installed on the gearbox front face.

Main characteristics 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 by the Digital Control Unit - Position transmitter: resolver type.



FUEL SYSTEM

ARRIUS 1

Training Notes

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 by the Digital Control Unit

MANUAL METERING LEVER

Position transmitter Resolver type

FUEL METERING UNIT

CONSTANT ∆P VALVE

HP PUMP

HP FUEL PUMP AND METERING UNIT - GENERAL For training purposes only © Copyright - TURBOMECA


FUEL SYSTEM

Training Notes

ARRIUS 1

HP FUEL PUMP AND METERING UNIT DESCRIPTION HP fuel pump unit

Metering unit

The HP fuel pump unit includes:

Manual metering valve

- A shaft which drives the drive gear

The manual metering valve includes:

- A driven gear

- A rotary plate valve actuated by a control lever. The rotary plate valve has a fuel outlet orifice and a neutral notch

- A pressure relief valve

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

- Two lip seals which ensure the drive shaft sealing - A drain which evacuates any leaks overboard

Main metering valve - Two journal bearings which support the pump gears - A drive sleeve.


Electrically, the unit includes a stepper motor (electrical rotary actuator) to drive the metering unit and a resolver to transmit the metering unit position to the Digital Control Unit.


FUEL SYSTEM

ARRIUS 1

Training Notes

F

MANUAL METERING PRESSURE RELIEF METERING VALVE VALVE VALVE

0

To pressurising valve ELECTRICAL CONNECTOR

STOP ELECTRO-VALVE

HP PUMP UNIT

PRESSURE RELIEF VALVE

From LP pump

HIGH PRESSURE PUMP

JOURNAL BEARINGS DRIVEN GEAR LIP SEALS

DRIVE GEAR

RESOLVER

STEPPER MOTOR

REDUCTION GEAR

DRIVE SHAFT

DRIVE SHAFT DRAIN

HP FUEL PUMP UNIT

HP FUEL PUMP AND METERING UNIT - DESCRIPTION For training purposes only © Copyright - TURBOMECA


FUEL SYSTEM

Training Notes

ARRIUS 1

HP FUEL PUMP AND METERING UNIT OPERATION Engine normal operation

The manual metering valve increases or reduces the fuel flow:

The fuel delivered by the LP pump enters the HP pump after filtering. The fuel is then delivered by the HP pump through the internal ducts. A pressure relief valve returns the excess pressure to the HP pump inlet.

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

The fuel then enters the metering unit and flows to:

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

- The constant ∆P valve which maintains a constant difference of pressure on both sides of the metering unit by returning the excess fuel to the LP pump outlet through the ∆P return duct

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

- 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): the main orifice of the fixed plate faces the orifice of the plate valve and allows fuel flow to the metering unit • In manual operation, the metering unit is "frozen" in the position at the time of failure or of manual selection.

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

Engine shut-down - In normal operation or in case of power turbine overspeed, the engine shut-down is caused by the opening of the stop electro-valve which returns the fuel to the LP pump inlet - In manual operation, the engine shut-down is effected by closing the main and by-pass orifices of the fixed plate.



FUEL SYSTEM

ARRIUS 1

Training Notes

HIGH PRESSURE PUMP

PRESSURE RELIEF VALVE

MANUAL METERING VALVE

METERING VALVE

To pressurising valve By-pass orifice

ROTARY PLATE VALVE From LP pump

FIXED PLATE

+ -

Main orifice

MANUAL METERING VALVE (neutral position)

CONSTANT ∆P VALVE

To start electro-valve

To HP pump inlet

To LP pump inlet STOP ELECTRO-VALVE

HP FUEL PUMP AND METERING UNIT - OPERATION For training purposes only © Copyright - TURBOMECA


FUEL SYSTEM

Training Notes

ARRIUS 1

STOP ELECTRO-VALVE - GENERAL DESCRIPTION Function

Description

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

The stop electro-valve includes: - An electrical connector

Position

- An opening control coil A

- In the system: between the fuel metering valve outlet and the LP pump

- A closing control coil B

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

- A ball valve installed on a bistable reversible spring plate


- A fuel outlet orifice (to LP pump inlet)

- Type: bistable, ball type.

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



FUEL SYSTEM

ARRIUS 1

Training Notes

F

0


OPENING COIL A


STOP ELECTRO-VALVE

HP PUMP UNIT

SPRING PLATE

CLOSING COIL B BALL VALVE

Type Bistable, ball type

MOUNTING FLANGE

Fuel inlet (from fuel metering unit and constant ∆P valve)

Fuel outlet (to LP pump)

STOP ELECTRO-VALVE - GENERAL - DESCRIPTION For training purposes only © Copyright - TURBOMECA


FUEL SYSTEM

Training Notes

ARRIUS 1

STOP ELECTRO-VALVE - OPERATION Engine operation

Engine shut-down

The stop electro-valve is selected closed when start is initiated, and when the starter - generator and the starting system are electrically supplied.

The electrical supply of the A coil by the Digital Control Unit displaces the core in oposite direction. The ball valve lifts from its seat and allows the fuel to return to the pump inlet.

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

The stop electro-valve opening causes the fuel injection pressure to drop, which closes the pressurising valve and cuts the injection manifold supply.

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



FUEL SYSTEM

ARRIUS 1

Training Notes

CORE

OPENING COIL A

CORE

CLOSING COIL B

Fuel inlet (from constant ∆P valve) VALVE CLOSED ENGINE OPERATION

Fuel outlet (to LP pump)

VALVE OPEN ENGINE SHUT-DOWN

STOP ELECTRO-VALVE - OPERATION For training purposes only © Copyright - TURBOMECA


FUEL SYSTEM

Training Notes

ARRIUS 1

FUEL VALVE ASSEMBLY - GENERAL Function

Main components

The valve assembly ensures fuel distribution under certain conditions:

- Start electro-valve (3 way) - Pressurising valve

- To supply in priority the start injectors - Flow divider - To protect the start injectors from the risk of blockage due to carbonisation

- Purge screw.

- To give supply preference to one main injector at low fuel flow - To allow the manual purge of the system.

Position - In the system: between the metering unit and the injection system - On the engine: on a support secured at the upper part of the combustion chamber casing.

Main characteristics - Type: 1 electro-valve and 2 spring-loaded valves - Pressurising valve setting: 500 kPa (72.5 PSI) - Flow divider setting: 150 kPa (22 PSI).



FUEL SYSTEM

ARRIUS 1

Training Notes

FLOW DIVIDER

START ELECTRO-VALVE

PRESSURISING VALVE Preference injector supply

Fuel inlet (from metering unit)

P3 air Type 1 electro-valve 2 spring loaded valves Pressurising valve setting 500 kPa (72.5 PSI) Flow divider setting 150 kPa (22 PSI)

Main injector supply

Start injector supply

PURGE SCREW

FUEL VALVE ASSEMBLY - GENERAL For training purposes only © Copyright - TURBOMECA


FUEL SYSTEM

Training Notes

ARRIUS 1

FUEL VALVE ASSEMBLY - DESCRIPTION The valve assembly includes the start electro-valve, the pressurising 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 fuel inlet, the fuel outlet to the start injectors and the P3 air inlet for the start injector ventilation. The start electro-valve mainly includes: - Two opposed ball valves integral with a shaft and subjected to spring action in one direction and to the electro-valve winding in the other direction - Two filters

Flow divider In case of low fuel flow, the flow divider closes and the fuel flows only to the preference injector. This is done in order to preserve at least one injection point in the combustion chamber with an acceptable spraying quality-flow . The flow divider includes: - One valve, with leak rate, spring loaded closed (supply of 9 of the main injectors) - One restrictor, screwed into the flow divider body (supply of the preference injector).

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

- An electrical connector.

Pressurising valve The pressurising valve ensures fuel supply priority to the start injectors during starting. The pressurising valve includes a valve which is spring loaded closed.



FUEL SYSTEM

ARRIUS 1

Training Notes

PRESSURISING VALVE PURGE SCREW

FLOW DIVIDER Fuel outlet (to preference injector)

Fuel inlet (from metering unit)

Fuel outlet (to main injectors)

P3 air VALVE ASSEMBLY START ELECTRO-VALVE Fuel outlet (to start injectors)

FUEL VALVE ASSEMBLY - DESCRIPTION For training purposes only © Copyright - TURBOMECA


FUEL SYSTEM

Training Notes

ARRIUS 1

FUEL VALVE ASSEMBLY - OPERATION Six operating phases are considered: engine stopped, initial phase of starting, starting, normal running, rapid fuel flow decrease and engine shut-down.

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

Normal running (N1 > self-sustaining speed) Engine stopped There is no pressure in the system and no electrical supply to the accessories. The pressurising valve and the flow divider are closed, the start electro-valve is in the ventilation position.

When the engine reaches self-sustaining speed (approx. 50 % of N1), the electrical supply to the start electro-valve is cut. The start electro-valve closes the fuel supply to the start injectors and allows their ventilation by P3 air in order to prevent carbonisation.

Initial phase of starting (N1 < 10%)

Rapid fuel flow decrease

When start is selected, the start electro-valve coil is electrically supplied. The start electro-valve opens and allows the fuel supply to the start injectors.

When the fuel flow decreases rapidly, the flow divider closes and reduces the fuel supply to the main injectors. However, the flow is maintained to the preference injector to avoid engine flame-out.

Starting (N1 > 10%) It opens as soon as the fuel pressure is sufficient (about 500 kPa / 72.5 PSI which is obtained for an N1 speed of about 10%). When the fuel pressure is sufficient, the pressurising valve opens and supplies the main injection with fuel.

Shut-down When shut-down is selected, the closing coil of the stop electro-valve is electrically supplied and opens the the valve. The pressurising valve closes and the fuel supply to the injection system stops. The engine shuts-down.

The fuel first flows to the preference injector. The flow divider includes an internal jet (leak rate) which supplies the main injector manifold before the effective opening of the valve.



FUEL SYSTEM

Training Notes

ENGINE STOPPED

INITIAL PHASE OF STARTING (N1 < 10%)

P3

NORMAL RUNNING (N1 > self-sustaining speed)

ARRIUS 1

STARTING (N1 > 10%)

P3

RAPID FUEL FLOW DECREASE

SHUT-DOWN

FUEL VALVE ASSEMBLY - OPERATION For training purposes only © Copyright - TURBOMECA


FUEL SYSTEM

Training Notes

ARRIUS 1

START INJECTORS - GENERAL Function

Main components

The start injectors spray fuel into the flame tube during engine starting.

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

Position

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

- On the engine: around the combustion chamber casing.

Main characteristics - Quantity: 4 - Ventilation: by P3 air flow.



FUEL SYSTEM

ARRIUS 1

Training Notes

START ELECTRO-VALVE

START INJECTOR (with igniter plug)

FUEL SUPPLY HALF MANIFOLD

START INJECTOR Quantity 4

INJECTOR

INJECTOR AND IGNITER PLUG


INJECTOR

Ventilation By P3 air flow

START INJECTORS - GENERAL For training purposes only © Copyright - TURBOMECA


FUEL SYSTEM

Training Notes

ARRIUS 1

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 by means of inclined and displaced planes - An orifice plate provided in its centre with an orifice. The two injectors located close to the igniter plugs are mounted on inclined bosses with a sleeve to secure the combustion chamber. The two other injectors are mounted on flat bosses.



FUEL SYSTEM

ARRIUS 1

Training Notes INJECTOR (on inclined boss)

IGNITER PLUG

MOUNTING FLANGE INJECTOR

CIRCLIP


FILTER

JET HOLDER

SPRING ORIFICE PLATE


INJECTOR

SLEEVE

INJECTOR (on flat boss)

START INJECTORS - DESCRIPTION For training purposes only © Copyright - TURBOMECA


FUEL SYSTEM

Training Notes

ARRIUS 1

START INJECTORS - OPERATION Starting

Normal running

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

At the end of starting, the start electro-valve cuts off the start injector fuel supply and allows their ventilation with P3 air in order to prevent their carbonisation.

The igniter plugs ignite the fuel sprayed by the injectors into the combustion chamber.

The start injectors are continuously ventilated during the engine operation.

As soon as the pressurising valve opens the fuel flows to the main injectors. The fuel sprayed by the injectors is ignited and the combustion goes on.



FUEL SYSTEM

ARRIUS 1

Training Notes

MAIN INJECTOR SUPPLY

P3 air

START ELECTRO-VALVE (open)

IGNITER PLUG

START ELECTRO-VALVE (in ventilation position)

START INJECTOR VENTILATION

START INJECTOR SUPPLY

STARTING

NORMAL RUNNING

START INJECTORS - OPERATION For training purposes only © Copyright - TURBOMECA


FUEL SYSTEM

Training Notes

ARRIUS 1

MAIN INJECTORS - GENERAL Function

Main components

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

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

Position - On the engine: around the rear part of the combustion chamber casing.


- 5 injectors connected by a half-manifold, on the left side - 4 injectors connected by a half-manifold, on the right side - 1 injector connected by a pipe to the valve assembly. This is the "preference injector".

- Type: pre-vaporising injector - Quantity: 10 injectors with 1 "preference" injector - Fuel supply: through two half-manifolds and a pipe for the "preference" injector.



FUEL SYSTEM

ARRIUS 1

Training Notes

HALF-MANIFOLD SUPPLY (from valve assembly)

"PREFERENCE" INJECTOR FUEL SUPPLY

MAIN INJECTORS

Type Pre-vaporising injector Quantity 10 injectors with 1 "preference" injector Supply Through 2 half-manifolds and a pipe for the "preference" injector

LEFT HALF-MANIFOLD

RIGHT HALF-MANIFOLD

MAIN INJECTORS - GENERAL For training purposes only © Copyright - TURBOMECA


FUEL SYSTEM

Training Notes

ARRIUS 1

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 spraying jet. The injectors penetrate into the pre-vaporising tubes which are welded on the flame tube.



FUEL SYSTEM

ARRIUS 1

Training Notes

FILTER

CIRCLIP

PRE-VAPORISING TUBE

Fuel inlet

VAPORISED FUEL

AIR

MOUNTING FLANGE

EXTERNAL CASING FLANGE

JET FUEL

ARM

END

BODY

SPRAYING JET

PRE-VAPORISING SYSTEM MOUNTING FLANGE (welded on the flame tube)

INJECTOR MOUNTING FLANGE

MAIN INJECTORS - DESCRIPTION For training purposes only © Copyright - TURBOMECA


FUEL SYSTEM

Training Notes

ARRIUS 1

MAIN INJECTORS - OPERATION Normal operation

Rapid fuel flow decrease

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

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

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

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

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



FUEL SYSTEM

ARRIUS 1

Training Notes

PREFERENCE INJECTOR FUEL SUPPLY

PREFERENCE INJECTOR FUEL SUPPLY

MAIN INJECTOR FUEL SUPPLY

FLOW DIVIDER OPEN

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

NORMAL OPERATION

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

MAIN INJECTORS - OPERATION For training purposes only © Copyright - TURBOMECA


FUEL SYSTEM

Training Notes

ARRIUS 1

COMBUSTION CHAMBER DRAIN VALVE Function


This valve drains overboard any unburnt fuel remaining in the combustion chamber.

The drain valve includes:

Position - On the engine: at the bottom of the combustion chamber casing lower part.


- A union (screwed into the lower part of the combustion chamber casing) - A valve actuated by the pressure in the combustion chamber. It opens at engine shut-down to drain fuel. It closes during starting when the air pressure becomes higher than the setting

- Type: diaphragm

- A diaphragm which opens the valve when the pressure decreases in the combustion chamber

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

- A guiding sleeve which supports the diaphragm - An outlet union (to drain collector).



FUEL SYSTEM

ARRIUS 1

Training Notes

AIR PRESSURE (from combustion chamber)

FUEL UNION

Type Diaphragm Closing pressure 35 - 40 kPa (5 - 5.8 PSI) for N1 approx. 50%

DIAPHRAGM

VALVE OPEN

VALVE CLOSED

GUIDING SLEEVE

OUTLET UNION

FUEL (to drain collector) ENGINE SHUT-DOWN

ENGINE RUNNING

COMBUSTION CHAMBER DRAIN VALVE For training purposes only © Copyright - TURBOMECA


FUEL SYSTEM

Training Notes

ARRIUS 1

FUEL PIPES Left front view

Right rear view

- Pipe from valve assembly to main manifolds

- Start injection manifold

- Start injection manifold

- Air pipe for the ventilation of start injectors

- Main injection manifold

- Combustion chamber drain valve

- Pipe from HP pump unit to valve assembly

- Main injection manifolds.

- 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.



FUEL SYSTEM

ARRIUS 1

Training Notes PRESSURE TRANSMITTER PIPE

LP PUMP DRAIN

PIPE FROM VALVE ASSEMBLY TO MAIN INJECTORS AIR PIPE FOR THE VENTILATION OF THE INJECTORS

PIPE FROM STOP ELECTRO-VALVE TO LP PUMP

MAIN INJECTION MANIFOLD

FWD FWD FUEL INLET UNION

DRAIN OF THE HP PUMP AND METERING UNIT

START INJECTION/VENTILATION MANIFOLD DRAIN UNION

HP PUMP PIPE TO VALVE ASSEMBLY

COMBUSTION CHAMBER DRAIN VALVE

FUEL PIPES For training purposes only © Copyright - TURBOMECA


FUEL SYSTEM

Training Notes

ARRIUS 1

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



CONTROL SYSTEM

Training Notes

ARRIUS 1

CONTROL SYSTEM - GENERAL Functions


The control system is designed to automatically adapt the engine to the aircraft power requirements whilst remaining within defined limits.

- DCU type: single channel digital electronic

The main functions of the control system are the following:

- Electrical supply: redundant.

- Start control

Main components

- Speed control and miscellaneous limitations

- Digital Control Unit (DCU)

- Manual control

- Engine (engine and systems)

- Overspeed protection

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

- Manual control type: mechanical

- Fault monitoring and processing.

Position The control system components are located on the engine and on the aircraft. The DCU is supplied by the engine manufacturer but installed in the aircraft.



CONTROL SYSTEM

Training Notes

AIRCRAFT (various systems)

ARRIUS 1

DIGITAL CONTROL UNIT (DCU)

MAIN FUNCTIONS

- Start control - Speed control and miscellaneous limitations - Manual control - Overspeed protection

ENGINE (engine and systems)

- Fault monitoring and processing

CONTROL SYSTEM - GENERAL For training purposes only © Copyright - TURBOMECA


CONTROL SYSTEM

Training Notes

ARRIUS 1

CONTROL SYSTEM - DESCRIPTION This part briefly describes the whole control system : the DCU inputs and outputs, the Digital Control Unit, the aircraft and engine systems.

The DCU is a single channel, digital controller. It is installed in the aircraft cargo compartment.

DCU inputs and outputs

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

Inputs from the aircraft - Logic inputs - Analog inputs.

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

Inputs from the engine

Aircraft and engine systems

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

Digital Control Unit (DCU)

Various aircraft and engine systems are connected to the control system. These systems are dealt with in corresponding chapters.

- Logic outputs (indicating lights, relays) - Serial data link. Outputs to the engine - Accessories (electro-valve, fuel metering unit).



CONTROL SYSTEM

ARRIUS 1

Training Notes

28V AIRCRAFT SUPPLY CIRCUIT

ALTERNATOR

SUPPLY AIRCRAFT

ENGINE

DIGITAL CONTROL UNIT LOGIC INPUTS

ANALOG INPUTS (T1 probe, collective pitch, rudder control bar, trims)

CONTROL SYSTEM

POWER TURBINE OVERSPEED PROTECTION (analog)

SENSORS (rotation speed, air pressure, thermocouples ...) ENGINE ACCESSORIES (electro-valve, fuel metering unit, sensors ...)

LOGIC OUTPUTS (indicating lights, relays)

SERIAL DATA LINK

CONTROL SYSTEM - DESCRIPTION For training purposes only © Copyright - TURBOMECA


CONTROL SYSTEM

Training Notes

ARRIUS 1

CONTROL SYSTEM - OPERATION (1) GENERAL PRINCIPLES This part is an introduction to the operation of the control system. Prior to dealing with the various functions, it is worth remembering the engine configuration and the installation requirements.

Engine configuration The engine includes a gas generator which provides mechanical power to a power turbine which is connected to a receiver. The gas generator (compressor, combustion chamber, turbine) has its operating point defined by the air flow, the fuel flow, the rotation speed and the turbine entry temperature. The only available physical parameter for control purposes is the fuel flow injected into the combustion chamber. The power turbine has its operating point defined by the balance between the power provided by the gas generator and the power required to drive the helicopter rotor; that is to 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 constant in all operating conditions and whatever the load applied) - A max. torque (C) of the power shaft (max. limit imposed by the mechanical transmission and mainly by the main gearbox of the helicopter). The engine requirements are the following: - A power turbine rotation speed (N2) maintained within given limits (in fact, almost constant because it is connected to the helicopter rotor). An overspeed protection is also required in case of failure of the transmission 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 by the hot section strength and particularly by the turbine blades) - 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.


CONTROL SYSTEM

ARRIUS 1

Training Notes

GAS GENERATOR

POWER TURBINE

RECEIVER NR

TURBINE

COMPRESSOR

N2 speed

N1 speed Air flow G

Main gearbox

Gas

Torque C

Compressor outlet pressure P3

Turbine entry temperature TET

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

COMBUSTION CHAMBER Fuel flow Q FUEL CONTROL UNIT


INPUT SIGNALS

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

GENERAL PRINCIPLES

CONTROL SYSTEM - OPERATION (1) For training purposes only © Copyright - TURBOMECA


CONTROL SYSTEM

Training Notes

ARRIUS 1

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

Manual control

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

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

Start control

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

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

Twin-engine configuration

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

The control system takes into account the twin-engine configuration (synchronization) and the case of one engine failure.

Speed control

The power turbine overspeed protection system automatically shuts down the engine when the overspeed threshold is reached.

Overspeed protection

Its main function is to maintain the power turbine rotation speed constant by metering the fuel flow. The control loop ensures in fact the power turbine rotation speed control and various limitations: -

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


Monitoring and fault processing The control system also ensures engine monitoring and fault processing.


CONTROL SYSTEM

Training Notes STARTING

ARRIUS 1 MANUAL CONTROL

- Fuel flow - Idle speed - Acceleration


CONTROL SYSTEM

METERING VALVE

OVERSPEED PROTECTION

SPEED - N2 speed - N1 speed

MONITORING AND FAULT PROCESSING

- Acceleration / deceleration

Q

- Fuel flow

MAIN FUNCTIONS OF THE CONTROL SYSTEM



CONTROL SYSTEM

Training Notes

ARRIUS 1

CONTROL SYSTEM - OPERATION (3) START CONTROL

Starting control

- ∆Q flow correction law. Fuel flow correction as a function of: • the t4.5 • the t4.5* datum which varies according to the N1 rotation speed

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

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

The start control includes: the fuel flow control during starting control, the N1 idle control and the acceleration control.

The fuel flow Q injected into the combustion chamber is equal to (Q1+Q2)-∆Q Thus, the fuel flow Q* datum is controlled as a function of determined laws: - Q1 basic flow law. Flow determined to obtain ignition as a function of: • the t1 air temperature • the t4.5 residual temperature - Q2 start flow law. Flow determined to obtain the acceleration as a function of: • the N1 rotation speed • a k factor which varies as a function of the atmospheric pressure P0



CONTROL SYSTEM

ARRIUS 1

Training Notes

∆Q

=

t4.5

N1 (%)

255

∆t4.5* t4.5*

65

648

N1

0

t4.5*

472

0

55

76

N1 idle

68 160

670

∆t4.5

∆Q FLOW CORRECTION LAW

N1

t4.5 DATUM (limit) AS A FUNCTION OF N1 0 Time

Q2

30

Q1

t4.5 < 50°C

39

∆Q

t4.5 > 50°C

t4.5 15

30

t1 P0

61.5

N1

t1 0

+60

FUEL FLOW Q*

=

k

-60 -50

Q

Q1 + Q2

1

0

68

N1

FLOW LIMITATION LAW 0

Q1 BASIC FLOW LAW

1023

P0

Q2 START FLOW LAW

START CONTROL



CONTROL SYSTEM

Training Notes

ARRIUS 1

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

N1 idle control To start the engine a 3-position selector is moved to either Training or Flight.

3 - N2 idle: at the end of the acceleration, the N2 is stabilised at a controlled speed as function of determined laws:

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

• N2 speed control law: the actual N2 speed is compared with the N2* idle datum (approx. 90%). The N2 controller provides an N1* datum

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

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

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

4 - Acceleration up to the N2 nominal speed: The acceleration is commanded when the mode selector is set to the "Flight" position: the two engines have the same acceleration rate.

Acceleration control

5 - The system stabilises the engine at 100% N2

2 - Acceleration up to N2 idle ensured by the speed control loop as a function of determined laws: • N2 speed control law: the N2 controller provides a variable N1* datum. The N1* datum varies according to the actual acceleration of the power turbine (law ∆N1/ ∆N2; to avoid overtorque).

6 - Training mode control: if the selector is moved from Flight to Training, the engine will decelerate to 90% N2. 7 - If the other engine stops the control unit will maintain a minimun N2 of 85% (if the pilot increases the collective pitch).

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



CONTROL SYSTEM

ARRIUS 1

Training Notes N1 (%)

N1 CONTROL N1

Flight 80

5

N1 Control unit

Fuel metering unit

Q

N1* = 68% if N2 < threshold

N2 = 100%

N2 CONTROL

4 6

N2

N2 idle 75

N2 = 90%

N1 Control unit

N2*

N1 (%)

7

Q*

Fuel metering unit

Q

N1 IDLE

2

ENGINE ACCELERATION: RAMPS OF N1* ACCORDING TO ACTUAL N2

3

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

4

ACCELERATION: N2* RAMP

5

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

6

DECELERATION: N2* RAMP WHEN PASSING FROM FLIGHT TO TRAINING

7

TRAINING MODE CONTROL

N2 (%)

70 85

90

N1

1

1 96

0

N1*

3

2

N1 idle 68

N2 Control unit

time

START CONTROL (CONTINUED)



CONTROL SYSTEM

Training Notes

ARRIUS 1

CONTROL SYSTEM - OPERATION (5) SPEED CONTROL - GENERAL

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

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).

Static droop compensation

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

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

The gas generator control unit measures the speed datum (N1*) and the actual speed (N1) and determines a flow datum in order to adapt the gas generator to the operating conditions. The fuel metering unit receives the flow datum (Q*) and calculates the actual flow (Q).

In operation, points 1, 2 and 3 are obtained and the static droop is then compensated; this means: constant power turbine speed (and therefore rotor speed) in all operating conditions. In transient operation, the power turbine speed varies, but the control unit operates quickly to return the speed to its nominal value, within the value of the static droop.

N1/N2 relation (control unit static droop) In this type of control system, the N1 speed is made inversely proportional to N2. The N1/N2 relation illustrates this proportionality and the N2 variation is called "static droop" (St). The static droop ensures the system stability, but it is not acceptable because the helicopter rotor requires a constant speed.



CONTROL SYSTEM

ARRIUS 1

Training Notes N1 N2

N1

N2

N1

Flow Q Fuel metering unit Q* flow datum Gas generator control unit

N1 / N2 RELATION CURVE (control unit static droop) N1 Speed

N1

3

N1* speed datum

COLLECTIVE PITCH

2

h

COLLECTIVE PITCH

tc

iu ed

pi

m

1

gh hi

N2 Speed Power turbine control unit

N2

Static droop

m h

h

tc pi

tc pi

w

lo

N2

N2* speed datum SPEED CONTROL LOOP

STATIC DROOP COMPENSATION CURVE

SPEED CONTROL - GENERAL



CONTROL SYSTEM

Training Notes

ARRIUS 1

CONTROL SYSTEM - OPERATION (6) SPEED CONTROL - CONTROL LOOP We can distinguish the following functional assemblies:

N1 control unit

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

- Compares the N1* datum to the actual speed N1

- The N1 control unit (speed control unit, flow limiter) - The fuel metering unit.

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

Fuel metering unit

N2 control unit

- Ensures the Q* flow signal conversion

- Determines an N2* datum as a function of the rotor collective pitch and of the tail rotor pitch α0, of the "trims" α1 and of an N20 datum speed

- Outputs the signal to the stepper motor of the fuel metering valve.

- Compares this datum to the actual N2 and calculates the difference

Speed control - Example of transient condition

- Processes this difference with a proportional control

When the collective pitch increases the XCP signal gives an initial increase of the N1* datum. The N2 speed drops. The N2 control unit detects the drop and calculates a new N1* datum. The N1 control unit processes this datum according to certain limitations (acceleration, torque, flow…) and determines a Q* flow datum which is transmitted to the metering unit. The flow increases, the N1 speed increases, the N2 speed returns to its nominal value.

- Provides an N1* datum - Controls the acceleration and deceleration, limits the torque (the min. selector selects the lowest signal) and ensures the N1 max. and min. stops.

Anticipator A signal proportional to the collective pitch angle, called XCP, is added to the N1* datum.



CONTROL SYSTEM

ARRIUS 1

Training Notes Signals

Control unit P : Proportional I : Integral

Q

α0: Rotor collective pitch and rudder control bar α1: Balancing and rotor trims *: Datum N20: N2 reference = 100% XCP: Collective pitch

Load C

FUEL METERING UNIT Q

Metering unit

Q* Max. Q Min. Q N1 CONTROL UNIT

Q* N1 XCP

N1* Power turbine speed N2

Max. N1 Min. N1

time

Minimum selector

time

N1*

N1*

Acceleration / Deceleration

Torque

Fuel flow Q N2 CONTROL UNIT

N1*

P ∆N2

time Gas generator speed N1

N2 N2* α1

time

N20 α0

SPEED CONTROL - CONTROL LOOP



CONTROL SYSTEM

Training Notes

ARRIUS 1

CONTROL SYSTEM - OPERATION (7) SPEED CONTROL - MISCELLANEOUS LIMITS Beyond the speed control, the N2 speed control unit ensures some limitations. It acts on the N1* datum transfer: - Acceleration and deceleration limitations

Overtorque limitation This limitation avoids torque overshoot due to the dynamics of the control loop during transient load increase. The overtorque limitation limits the variation rate of N1* datum as follows:

- Transient overtorque limitation - N1 speed limitation.

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

Acceleration and deceleration limitations These limitations ensure a protection against:

- If the change is negative: no effect

- Compressor surge in case of rapid acceleration (collective pitch increase)

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

- Flame out in case of rapid deceleration (collective pitch decrease). The system limits the variation rate of the N1* datum as a function of the time t (dN1*/dt). The max. rating is comprised between + 13%/s in acceleration and - 25%/s in deceleration and depends on the P0 atmospheric pressure. It decreases when the pressure decreases (slower acceleration and deceleration).



CONTROL SYSTEM

ARRIUS 1

Training Notes N1*

N1*

N1*

High P0

N1 limitation (max. N1, min. N1)

Low P0

Controls t1 P0

Low P0 High P0

N1*

time

time

Acceleration rate

Deceleration rate

N2

Minimum selector

time N1*

N1*

dN2 / dt < 0

Overtorque limitation

(dN2 / dt)

Acceleration and deceleration limitation

N1*

N1*

A N1*

B

A: - N2 speed drop - N1* increase without dN2 / dt > 0 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

P0

time OVERTORQUE LIMITATION

ACCELERATION / DECELERATION CONTROL AND OVERTORQUE LIMITATION

SPEED CONTROL - MISCELLANEOUS LIMITS



CONTROL SYSTEM

Training Notes

ARRIUS 1

CONTROL SYSTEM - OPERATION (8) SPEED CONTROL - MISCELLANEOUS LIMITS (CONTINUED)

N1 speed limitation

Flow limitation

The N1 speed limitation system provides the max. rating while protecting the engine. The ratings are selected by the pilot (i.e.: OEI 2 min. 30 sec. rating, training 2 min. 30 sec. rating control…). Limitation also depends on the atmospheric conditions (P0 pressure, t1 temperature).

The control ensures two fuel flow limitations: - Max. fuel flow. This limitation is calculated as a function of the compressor outlet pressure (P3). It is a max. power stop. There are in fact two stops: a max. flow stop in normal operation and a max. flow stop in training mode

max. N1*: N1 (t1) - ∆N1 (P0) The min. N1 speed is also limited to avoid operation at critical ratings. A push button on collective pitch lever selects between OEI 2 min. 30 sec. rating and OEI 30 min. rating.

- Min. fuel flow. This limitation is calculated as a function of the P0 atmospheric pressure in order to avoid flame out especially during rapid load decrease.

A training-normal selector allows one engine to be selected to training. The engine selected to training is reduced to idle (90% N2), and the other engine has its max. power limited to take-off power.



CONTROL SYSTEM

ARRIUS 1

Training Notes

N1 (%) OEI 2 min. 30 sec.

103 102 101

T/O

100

P3 P0

Max. Q Min. Q

OEI 30 min.

NORMAL

Q*

Q*

Normal configuration

99

N1 limitation (max. N1, min. N1)

MCP t1 (°C) -50

0

15

TRAINING

Controls t1 P0

MAX. FLOW

N1*

+50

Minimum selector

0

P3

∆N1 (%) N1*

N1*

1,3 Q* 0

500

1013 P0

Overtorque limitation

MIN. FLOW

Acceleration and deceleration limitation

0

Max. N1* = N1(t1) - ∆N1(P0)

P0 (dN2 / dt)

N1*

N1*

P0

N1 SPEED LIMITATION

FLOW LIMITATION

SPEED CONTROL - MISCELLANEOUS LIMITS (CONTINUED)



CONTROL SYSTEM

Training Notes

ARRIUS 1

CONTROL SYSTEM - OPERATION (9) MANUAL CONTROL

Flow range of the manual control

This system ensures a manual control of the fuel flow. It is used in case of a failure of the automatic control system. In most cases, a control system failure locks the metering valve in its position at time of failure. The manual control acts on a valve of the hydromechanical control unit located between the fuel pump and the metering unit. This valve will either cause a reduction of flow through the main valve or allow an increased flow in bypass of the main valve.

Control positions of the manual metering valve

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 fully closed: 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 locked at any flow, at the neutral notch:

- "Normal" position. Neutral position, the flow is controlled by the metering unit - "Flow decrease" range. The manual metering valve reduces the section of the direct passage and thus the fuel flow - "Flow increase" range. The fuel flow by-passes the metering unit, and thus allows the fuel flow increase whilst limiting the flow to the "frozen" metering unit.


- Manual valve effect with the main metering valve fully open:

All the fuel flow range is open between the fully closed flow (-45°) and the fully open flow (45°) - Reduction notch: The reduction notch ensures a min. flow to avoid flame out in all conditions. Note: An auto-manual selector is used for automatic control failure training. When selected to manual, the stepper motor is frozen and the engine has to be controlled manually.


CONTROL SYSTEM

ARRIUS 1

Training Notes N

Fuel flow

Q3 (controlled max. flow)

full

yo

pen

Q=0

at the ne fully ut clos ed ral n otc h

Q

Q

MANUAL INCREASE CONTROL POSITIONS OF THE MANUAL METERING VALVE

valv e

ny

ring in m

lve

ma the

m

th e

effe

ct w

ith

ef fe ct wi th

lve

lv

l va

ua an

nua

M

nua

g

Ma

Q1 (no flow)

Ma

Q2 (min. flow at the reduction notch)

l va

N

meteri n ain

al ve

lve

MANUAL DECREASE

Q

va

ma the ct w

ith

X (any flow)

effe

Q=0

ete

lo c

in m

Q≠0

ke

ete

da

ta

ring

N

fl o

val

w

ve

NORMAL (N)

Valve stop closed (-45°)

Neutral notch range with no effect (±5°)

Valve stop open (+45°)

Valve position (°)

FLOW RANGE OF THE MANUAL CONTROL

MANUAL CONTROL



CONTROL SYSTEM

Training Notes

ARRIUS 1

CONTROL SYSTEM - OPERATION (10) OVERSPEED PROTECTION The protection against power turbine overspeed automatically stops the engine when an overspeed threshold is reached.

In the event of an overspeed (112 +3%), the system operates as follows: - Overspeed detection

The protection system includes: - The overspeed module of the Digital Control Unit (analog processing)

- Electrical supply to the stop electro-valve (shut-down order) - Overspeed indication.

- The power turbine speed sensors - Some control and monitoring components (aircraft overspeed test unit) - The stop electro-valve (to shut-off the injector fuel supply when electrically supplied).

After the overspeed operation a specific procedure allows the rearming of the system. A cross monitoring system between the two DCUs inhibits the operation of the overspeed protection system of the engine remaining in operation.

Operation During starting, the system is tested at approximately 25% N2. In normal operation, the power turbine speed is stabilised at around 100% by the control unit (nominal speed).



CONTROL SYSTEM

ARRIUS 1

Training Notes N2 PHONIC WHEEL

28V aircraft supply

POWER TURBINE

N2 signals

Rearming and test signals

OVERSPEED MODULE OF THE DIGITAL CONTROL UNIT

SENSOR

Cross monitoring

Indication


Stop electro-valve

OVERSPEED MODULE DIAGRAM N2 (%) OVERSPEED Aircraft Q

STOP ELECTRO-VALVE

OVERSPEED TEST UNIT

112 ± 3 100

NOMINAL SPEED

SYSTEM TEST

25

PRINCIPLE OF THE POWER TURBINE OVERSPEED PROTECTION

0

t

SPEED THRESHOLD DIAGRAM




CONTROL SYSTEM

Training Notes

ARRIUS 1

CONTROL SYSTEM - OPERATION (11)

Operation

SPEED UNIT - OVERSPEED DETECTION SYSTEM

Power-up

Function

When N2 ≤ 25%, the push button and the arming indicating light "S" are electricaly supplied.Rearming is possible.

The overspeed detection system stops the engine when the power turbine rotation speed (N2) reaches a given value.

Overspeed test

Position

An OVERSPEED TEST push button allows the checking of the detection system operation.

The overspeed detection system is part of the speed unit.

When the TEST push button is depressed, the oscillator operates and simulates a 112% power turbine overspeed.


The test is inhibited at power turbine rotation speeds higher than 25%.

- Analog system

At each starting, when N2 > 25%, the push button and the arming indicating light "S" shut-off.

- 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 turbine shaft - A speed printed circuit board connected to the other engine DCU. This printed circuit board includes a monostable relay V, a bistable relay S-S', 25% and 112% detection modules and a 112% N2 oscillator - A stop electro-valve (ECA) - One overspeed test box for the two engines, which includes the TEST and REARMING push buttons and OVERSPEED (OVSP + indicating light) and ARMING (S + indicating light) indications.


Note: The OVERSPEED and ARMING indicating lights and the push buttons are located in the luggage compartment. Overspeed The overspeed detection system monitors the N2 speed through two different channels. If the signals reach the given thresholds (112 ±3% N2), the system opens the stop electro-valve and provides the overspeed signal. The engine stops. The overspeed detection system also controls the mutual lock of both engine protection loops. This lock prevents an engine being shut-down through the N2 overspeed protection loop if the other engine has already suffered an overspeed shut-down.


CONTROL SYSTEM

ARRIUS 1

Training Notes

Test Oscillator

SYSTEM POWER ON (N2 ≤ 25%) - Supply of the arming signal "S" + indicating light (up to 25% of N2) - Rearming (if necessary)

S

112%

N2

Stop electro-valve Engine shut-down

OVERSPEED (N2 = 112 ± 3%) -

N2

V

OVERSPEED TEST - Oscillator supply 112%* - Oscillator inhibited for N2 > 25%

112%

"OVSP" + 2nd engine inhibition

V monostable relay supply S bistable relay supply Stop electro-valve supply Overspeed signal "OVSP" supply + indicating light - 2nd engine system inhibition

25% S'

"S" + 25%

Rearming Circuits which are inhibited if N2>0%

SPEED UNIT - OVERSPEED DETECTION SYSTEM



CONTROL SYSTEM

ARRIUS 1

Training Notes

CONTROL SYSTEM - OPERATION (12) TWIN-ENGINE CONFIGURATION

Configuration description

Load sharing principle

The helicopter rotor is driven by the two engines through the main gearbox and the free wheels.

In normal conditions, the helicopter rotor is driven by the two power turbines; thus: NR = kN2 eng 1 = kN2 eng 2

Each engine has its own control unit which includes: - A power turbine N2 speed control unit (calculation of the N1* datum in relation to various parameters) - A gas generator N1 speed control unit (metering of the fuel flow Q to keep the N1 speed constant and equal to the N1* speed datum). The N2 control units of the two engines receive signals from the same collective pitch control ("anticipator" link).

The speed signals received by the two control units are the same, so are the collective pitch signals. The control units then determine identical datums which are kept constant by the fuel metering devices. As the power is linked to the N1 speed and as the power turbine efficiency varies very little from one turbine to another, 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 trim control.

Operation on a single engine In this case, the operating engine provides the power and the other is disengaged through the free wheel. The engine speed limit is represented by the gas generator speed; OEI 2 min. 30 sec. rating.



CONTROL SYSTEM

ARRIUS 1

Training Notes

HELICOPTER ROTOR

Main gearbox

COLLECTIVE PITCH

OPERATING POINT ON ONE ENGINE (same power supplied by a single engine)

FREE WHEEL N1

Max.

OPERATING POINT ON TWO ENGINES

POWER TURBINE GAS GENERATOR Q

N2

N1

Min.

N1* N2 N2 CONTROL UNIT

N1 CONTROL UNIT

N2 CONTROL UNIT

CONTROL PRINCIPLE

CONTROL DIAGRAM




CONTROL SYSTEM

Training Notes

ARRIUS 1

CONTROL SYSTEM - OPERATION (13) TRAINING MODE This system is designed to simulate an engine failure. During flight, the failure of one engine is simulated by switching the "STOP/TRAINING/FLIGHT" selector of the chosen engine to the "TRAINING" position. Then, the engine is controlled in training idle mode (90% N2). Thus, the power turbine is disengaged from the helicopter main gearbox. The other engine operates in the "TRAINING FLIGHT" (Training OEI) mode. The "TRAINING FLIGHT" mode is identical to the "FLIGHT MODE" but uses derated N1 stops in order to avoid the use of the OEI ratings.The working rating is then the MTOP. However, the engine operating in the training idle mode is able to deliver the required power in the event of a real failure of the other engine. The speed is controlled at a training speed of 90% N2 and the anticipator function is cancelled.



CONTROL SYSTEM

ARRIUS 1

Training Notes

FLIGHT

FLIGHT

TRAINING

TRAINING

STOP

STOP

DCU ENGINE 1

"TRAINING" indication

ENGINE 1 REDUCE TO 90% N2

DCU ENGINE 2

ENGINE 2 LIMITED TO MAX. TAKE-OFF POWER

TRAINING MODE



CONTROL SYSTEM

Training Notes

ARRIUS 1

CONTROL SYSTEM - OPERATION (14) MONITORING AND FAILURE PROCESSING The control system ensures a continuous monitoring (built in test equipment) of various parameters: circuit continuity, signal validity, tests before starting, supply monitoring. There are three predetermined levels of failure: major failure, minor failure and loss of redundancy.

Recovery laws In case of defective operation or hardware failures, the Digital Control Unit can continue to operate, but only from recovery values. The Digital Control Unit uses recovery laws for the following failures:

Major failure In case of a major failure, the stepper motor is "frozen" and the manual control valve can be used (e.g.: metering unit failure, loss of two N1 or N2 signals, loss of two power supplies, DCU failure).

- P0 failure - T1 failure - t4.5 failure

Minor failure

- P3 failure

In case of a minor failure, the stepper motor operates normally and the control system operates from a recovery law (e.g.: loss of one sensor without redundancy).

- Collective pitch failure - Trim failure.

Loss of redundancy In the event of loss of redundancy, the system continues in normal control and maintenance action is necessary after flight (e.g.: loss of one N1 or N2 sensor, loss of one power supply).



CONTROL SYSTEM

ARRIUS 1

Training Notes

SUPPLY

INTERNAL CHECKS - Content of memories - Calculations - Internal supply - ...

EXTERNAL CHECKS - Continuity - Sensor insulation - Lack or evidence of signals - …

RECOVERY LAWS (minor failures) - P0 failure - T1 failure - t4.5 failure - P3 failure - Collective pitch failure - Trim failure

WARNINGS - Major failure - Minor failure - Loss of redundancy


OPERATION PRINCIPLE

MONITORING AND FAILURE PROCESSING



CONTROL SYSTEM

Training Notes

ARRIUS 1

DIGITAL CONTROL UNIT - GENERAL Function

Main components

The Digital Control Unit controls and monitors the engine operation.

The Digital Control Unit includes the following main units :

Position

- Interconnection unit

It is installed in the helicopter baggage compartment.

- Power supply unit


- Speed unit - Output unit

- DCU type: single channel, digital electronic - Processor unit - Design: modular - Input unit - Electrical supply: redundant. - 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 of the interconnection unit.



CONTROL SYSTEM

ARRIUS 1

Training Notes DCU type Single channel digital electronic Design Modular Electrical supply Redundant DIGITAL CONTROL UNIT (helicopter baggage compartment)

PIN

TIE BOLT

CONNECTORS

INPUT UNIT

PROCESSOR UNIT OUTPUT UNIT

SPEED UNIT EARTH BRAID MOUNTING FLANGE POWER SUPPLY UNIT

INTERCONNECTION UNIT

MOUNTING (with anti vibration device)

IDENTIFICATION PLATE

DIGITAL CONTROL UNIT - GENERAL For training purposes only © Copyright - TURBOMECA


CONTROL SYSTEM

Training Notes

ARRIUS 1

DIGITAL CONTROL UNIT - FUNCTIONAL DESCRIPTION (1) DCU inputs

From the engine

From the aircraft

- T1 temperature probe

- Overspeed TEST and REARM selector - FLIGHT - TRAINING - STOP selector - OEI 2 min. 30 sec. - OEI 30 min. selector - AUTO - MANUAL selector

- N1 speed sensors - N2 speed sensors - P3 air pressure sensor - t4.5 thermocouples

- Collective pitch and tail rotor pitch α0

- Fuel metering unit resolver.

- Trims (balance and rotor) α1

Power supply

- Cross monitoring (overspeed)

- 28 V Aircraft supply circuit

- Serial data link.

- Engine alternator.



CONTROL SYSTEM

ARRIUS 1

Training Notes

28V AIRCRAFT SUPPLY CIRCUIT AIRCRAFT

ALTERNATOR SUPPLY

- T1 TEMPERATURE PROBE

- OVERSPEED TEST - OVERSPEED REARMING - FLIGHT - TRAINING - STOP SELECTOR

ENGINE

DIGITAL CONTROL UNIT (ENGINE 1)

- N1 SPEED SENSORS

- OEI 2 min. 30 sec. - OEI 30 min. SELECTOR

- N2 SPEED SENSORS

- AUTO - MANUAL SELECTOR

- P3 AIR PRESSURE SENSOR

- COLLECTIVE PITCH AND TAIL-ROTOR PITCH α0

- t4.5 THERMOCOUPLES

- TRIMS α1

- FUEL METERING UNIT RESOLVER

- SERIAL DATA LINK


DCU INPUTS

DIGITAL CONTROL UNIT - FUNCTIONAL DESCRIPTION (1) For training purposes only © Copyright - TURBOMECA


CONTROL SYSTEM

Training Notes

ARRIUS 1

DIGITAL CONTROL UNIT - FUNCTIONAL DESCRIPTION (2) DCU outputs

To the engine

To the aircraft

- Stop electro-valve

- ∆N1 indicator

- Fuel metering unit

- Indicating lights • Overspeed • Overspeed armed • Contingency power • Minor / redundancy failures (amber GOV) • Major failure (red GOV) • Training.

- P3 air pressure sensor - T1 probe.

- Start control relay - Serial data link - Cross monitoring.



CONTROL SYSTEM

ARRIUS 1

Training Notes

ENGINE

AIRCRAFT

- ∆N1 INDICATOR - OVERSPEED INDICATING LIGHT - OVERSPEED ARMED INDICATING LIGHT - CONTINGENCY POWER INDICATING LIGHT


STOP ELECTRO-VALVE - FUEL METERING UNIT

- MINOR/REDUNDANCY FAILURES INDICATING LIGHT (amber GOV)

- P3 AIR PRESSURE SENSOR

- MAJOR FAILURE - T1 PROBE

INDICATING LIGHT (red GOV) - TRAINING INDICATING LIGHT - START CONTROL RELAY - SERIAL DATA LINK


DCU OUTPUTS

DIGITAL CONTROL UNIT - FUNCTIONAL DESCRIPTION (2) For training purposes only © Copyright - TURBOMECA


CONTROL SYSTEM

ARRIUS 1

Training Notes

8 - MEASUREMENT AND INDICATING SYSTEMS - Measurement and indicating systems ........................................ - Speed measurement and indicating system ............................... • N1 speed sensor (77-10-01)........................................................ • N2 speed sensors (77-10-02) ...................................................... - Gas temperature measurement and indicating system (77-20-01) .......................................................................... • Thermocouple probes and t4.5 conformation box (77-10-03) .. - Torque measurement and indicating system ............................. • Torque transmitter (77-10-03) ........................................................ - Miscellaneous indications ............................................................ • Indicators.................................................................................... • ∆N1 measurement and indicating system ................................ • Display system ............................................................................

8.2 8.4 8.6 8.10 8.14 8.16 8.20 8.24 8.26 8.26 8.28 8.30 to 8.33



MEASUREMENT AND INDICATING SYSTEMS

ARRIUS 1

Training Notes

MEASUREMENT AND INDICATING SYSTEMS Functions

Miscellaneous measurement and indicating systems

The measurement and indicating system provides the following functions:

- N1 gas generator rotation speed

- It allows to check that the engine is operating within determined limits - It signals faults or abnormal changes of parameters

- N2 power turbine rotation speed - t4.5 gas temperature - Engine torque

- It permits the checking of certain operating phases.

- Lubricating system (refer to chapter "OIL SYSTEM")

Miscellaneous indications

- Miscellaneous (indicating lights and monitoring).

- Electrical measurement system directly connected to indicators 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).




Training Notes

ARRIUS 1

N1 SPEED

t4.5 GAS TEMPERATURE

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 N2 SPEED

ENGINE TORQUE

MISCELLANEOUS (indicating lights and monitoring)

LUBRICATING SYSTEM

MEASUREMENT AND INDICATING SYSTEMS For training purposes only © Copyright - TURBOMECA



ARRIUS 1

Training Notes

SPEED MEASUREMENT AND INDICATING SYSTEM Function

General operation

This system measures the rotation speeds of the gas generator (N1) and the power turbine (N2).

The gas generator rotation speed (N1) signal is used for: - Engine control (starting, speed control loop)


- Indication (N1 and ∆N1).

- Type: phonic wheels and electromagnetic sensors - Sensor signals: frequency proportional to the rotation speed - Indication: digital in percentage.

Main components - N1 speed sensor

The N1 speed is an operating parameter as it reflects the engine power and serves to determine the limit ratings. The power turbine rotation speed (N2) signal is used for: - Engine control (speed control loop and overspeed protection) - Indication (associated with the NR rotation speed indication).

- N2 speed sensors - Connections with the DCU - Connections with the indicators.

Description Refer to sensors and to aircraft publications.




ARRIUS 1

Training Notes

COCKPIT


N1 gas generator rotation speed

Firewall

ENGINE

N1 SENSOR, Y2

CONTROL N1 SENSOR, Y1 ∆N1 indicator

STARTING

SPEED CONTROL LOOP


N1 SENSOR, Y3

N2 SENSOR, X1 N2 SENSOR, X3 N2 SENSOR, Y1 N2 SENSOR, Y3

N2 power turbine rotation speed + NR rotor rotation speed

N2 SENSOR, X2 NR signal

SPEED MEASUREMENT AND INDICATING SYSTEM For training purposes only © Copyright - TURBOMECA



ARRIUS 1

Training Notes

SPEED MEASUREMENT AND INDICATING SYSTEM N1 SPEED SENSOR - GENERAL

Function

Main components

The N1 speed sensor measures the rotation speed of the gas generator rotating assembly.

- Starter drive gear - Triple phonic wheel

Position - Upper part of the reduction gearbox.


- Triple electromagnetic sensor - Electrical connector (connections with the DCU and the N1 indicator).

- Type: electromagnetic - Quantity: 1 triple sensor (signals: Y1, Y2 and Y3) - Phonic wheel: • Quantity: 1 triple 2 wheels with 41 teeth 1 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.




ARRIUS 1

Training Notes

ELECTRICAL N1 SENSOR CONNECTOR - Connection with the DCU for Y1 and Y3 - Connection with the indicator for Y2

Type Electromagnetic TRIPLE N1 SENSOR

Quantity 1 triple sensor (Y1, Y2 and Y3) Phonic wheel - Quantity: 1 triple 2 wheels with 41 teeth 1 wheel with 37 teeth - Starter drive gear

STARTER DRIVE GEAR

TRIPLE PHONIC WHEEL

Signals (100% N1) Y2 and Y3: 7844 Hz for 11479 RPM Y1: 7078.7 Hz for 11479 RPM

N1 SPEED SENSOR - GENERAL




ARRIUS 1

Training Notes

SPEED MEASUREMENT AND INDICATING SYSTEM N1 SPEED SENSOR - DESCRIPTION - OPERATION

Description

Operation

The measurement and indicating system includes:

The phonic wheel rotates in front of the sensor and produces a pseudo sinusoidal alternating voltage.

- A triple phonic wheel (two wheels with 41 teeth and one with 37 teeth) - A triple electromagnetic sensor which includes three magnetic cores and coils. The gap between the phonic wheel and the sensor is 0.5 mm (0.018 inch). The gap is adjustable with a laminated shim. The three sensors are located in a single casing. The electrical connection is made through a 12 pin connector.

The alternating voltage frequency is proportional to the gas generator rotation speed and to the number of phonic wheel teeth.

F (Hz) =

Phonic wheel teeth number (d) x

Gas generator rotation speed

60 The Y1 and Y3 sensors are connected to the Digital Control Unit for the control system operation and the split indication. The Y2 sensor is connected to the speed indicator installed in the cockpit.




ARRIUS 1

Training Notes PHONIC WHEEL (d) N

F=

Gap Magnetic core 12 PIN CONNECTOR

ELECTROMAGNETIC SENSOR

Coil

Nxd 60

Gap = 0.5 mm (0.018 inch) (F)

PRINCIPLE OF SPEED MEASUREMENT STARTER DRIVE GEAR ∆N1 INDICATOR

DIGITAL CONTROL UNIT (control system) Y1 & Y3 PHONIC WHEEL

Y3 Y2 Y1 Y2

COCKPIT

DESCRIPTION SCHEMATIC DIAGRAM

N1 SPEED SENSOR - DESCRIPTION - OPERATION




ARRIUS 1

Training Notes

SPEED MEASUREMENT AND INDICATING SYSTEM N2 SPEED SENSORS - GENERAL

Function

Main components

The N2 speed sensors measure the rotation speed of the power turbine rotating assembly.

- Power turbine shaft - Triple phonic wheel

Position

- Triple electromagnetic sensors

- Front face of the reduction gearbox casing, around the front part of the power turbine shaft.

- Electrical connectors (connections with the DCU and the N2 indicator).

Main characteristics - 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 teeth 1 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 SENSORS REDUCTION GEARBOX CASING

ELECTRICAL CONNECTORS - Connection with the DCU - Connection with the N2 indicator TRIPLE N2 SENSORS

Type Electromagnetic Quantity 2 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 RPM X3 and Y3: 9844.9 Hz for 45438 RPM TRIPLE PHONIC WHEEL

POWER TURBINE SHAFT

N2 SPEED SENSORS - GENERAL




ARRIUS 1

Training Notes

SPEED MEASUREMENT AND INDICATING SYSTEM N2 SPEED SENSORS - DESCRIPTION - OPERATION

Description

Operation

The measurement and indicating system includes:

The phonic wheel rotates in front of the sensor and produces a pseudo sinusoidal alternating voltage.

- A triple phonic wheel (two wheels with 16 teeth and one with 13 teeth) - Two triple electromagnetic sensors which include, each, three magnetic cores and coils. The gap between the phonic wheel and the sensor is 0.5 mm (0.018 inch). The gap is adjustable with laminated shims. The six sensors are housed in a single casing. The electrical connection is made through two 12 pin connectors.

The alternating voltage frequency is proportional to the power turbine rotation speed and to the number of the phonic wheel teeth.

F (Hz) =

Phonic wheel teeth number (d) x

Gas generator rotation speed

60 The X1 and Y3 sensors are connected to the Digital Control Unit for the control system operation. The X3 and Y1 sensors are connected to the power turbine overspeed protection circuit. The X2 sensor is connected to the speed indicator located in the cockpit. The Y2 sensor is not used. Note: In a twin-engine configuration, the same indicator can display the rotor speed and the two power turbine speeds.




ARRIUS 1

Training Notes PHONIC WHEEL (d) N

F=

Gap

Gap = 0.5 mm (0.018 inch)

Magnetic core 12 PIN CONNECTORS

Nxd 60

(F)

ELECTROMAGNETIC SENSORS

PRINCIPLE OF SPEED MEASUREMENT

N2 SPEED INDICATOR

X2 X3 X2 X1

Y3 Y2 Y1 DIGITAL CONTROL UNIT (control system and overspeed protection)

PHONIC WHEEL

DESCRIPTION

X1-X3 Y1-Y3

COCKPIT

SCHEMATIC DIAGRAM

N2 SPEED SENSORS - DESCRIPTION - OPERATION




ARRIUS 1

Training Notes

GAS TEMPERATURE MEASUREMENT AND INDICATING SYSTEM Function

Description

This system monitors the gas temperature particularly during engine starting.

Refer to following pages.

General operation

As it is difficult to measure the gas temperature at the turbine inlet, the measurement is carried out at the gas generator outlet.

The t4.5 gas temperature is an operating parameter, particularly during engine starting.

Position

The signal from the thermocouples is used for:

- All the system components are located on the engine except the DCU and the t4.5 indicator.

- Engine control (start fuel flow control) - Indication (in degrees Celsius).

Main characteristics - Type: thermocouple probes - Indication: degrees Celsius.

Main components - Thermocouple probes - t4.5 conformation box - Digital Control Unit - t4.5 indicator (aircraft manufacturer's supply).




Training Notes

ARRIUS 1

t4.5 THERMOCOUPLE PROBE LOCATION

CONFORMATION BOX

t4.5 INDICATOR (cockpit)


FUEL METERING VALVE

GAS TEMPERATURE MEASUREMENT AND INDICATING SYSTEM For training purposes only © Copyright - TURBOMECA



ARRIUS 1

Training Notes

GAS TEMPERATURE MEASUREMENT AND INDICATING SYSTEM THERMOCOUPLE PROBES - t4.5 CONFORMATION BOX - GENERAL

Function

Main components

The thermocouple probes measure the gas temperature (t4.5) at the gas generator outlet.

- 4 double thermocouple probes - t4.5 conformation box.

Position - The thermocouple probes are installed on the power turbine diffuser casing. The tip of the probes is set in the gas flow before the power turbine nozzle guide vanes. - The t4.5 conformation box is secured by three bolts on a support located above the gas generator.

Main characteristics - Type: Chromel-Alumel - Quantity: 4 double probes - Connection: to the conformation box, in parallel.




ARRIUS 1

Training Notes

CONFORMATION BOX

Thermocouple type Chromel - Alumel Quantity 4 double probes Connection To the conformation box, in parallel DOUBLE THERMOCOUPLE PROBES

THERMOCOUPLE PROBES AND t4.5 CONFORMATION BOX - GENERAL




Training Notes

ARRIUS 1

GAS TEMPERATURE MEASUREMENT AND INDICATING SYSTEM THERMOCOUPLE PROBES - t4.5 CONFORMATION BOX - DESCRIPTION - OPERATION

Description

Operation

Each double thermocouple sensor includes:

A thermocouple probe produces an electromotive force proportional to the temperature difference between the hot junction (gas temperature) and the cold junction (indicator temperature).

- A cold junction subjected to the indicator temperature - A chromel conductor

This electromotive force is then provided through the conformation box:

- An alumel conductor - A hot junction subjected to the gas temperature.

- To the Digital Control Unit for the starting control system

The conformation box includes: - Some resistors to produce a uniform gas temperature indication for a given turbine inlet temperature

- To the gas temperature indicator (millivoltmeter) located in the cockpit.

- A shorting link support (not used).




ARRIUS 1

Training Notes Chromel wire CONFORMATION BOX

ELECTROMOTIVE FORCE

t°

RESISTORS

Alumel wire

RECEIVER COLD JUNCTION (indicator temperature)

TEMPERATURE INDICATOR

HOT JUNCTION (gas temperature)

THERMOCOUPLE PROBE RESISTORS

THERMOCOUPLE CONNECTOR ELECTRICAL CONNECTOR (Digital Control Unit and indicator)

COCKPIT

DIGITAL CONTROL UNIT SHORTING LINK SUPPORT (not used)

THERMOCOUPLES

CONDUCTOR CONNECTORS (Cr-Al) SHORTING LINK SUPPORT (not used)

CONFORMATION BOX

THERMOCOUPLE PROBES AND t4.5 CONFORMATION BOX - DESCRIPTION - OPERATION




ARRIUS 1

Training Notes

TORQUE MEASUREMENT AND INDICATING SYSTEM - GENERAL Function

Main components

The system provides an indication of engine torque measured on the intermediate gear of the reduction gear train.

- Hydraulic torquemeter

Position

- Torque indicator.

- Torque transmitter

- The hydraulic torquemeter is located in the double intermediate gear of the reduction gear train. - The torque transmitter is secured on the front face of the reduction gearbox casing.

Main characteristics - Torquemeter • Type: hydraulic - Transmitter • Type: resistive.




ARRIUS 1

Training Notes TORQUE LIMIT WARNING LIGHT

TORQUE MEASUREMENT - Hydraulic torquemeter located in the double intermediate gear of the reduction gear train - Resistive type torque transmitter COCKPIT

TORQUE INDICATOR

TORQUE TRANSMITTER

HYDRAULIC TORQUEMETER

INTERMEDIATE GEAR OF THE REDUCTION GEAR TRAIN

GENERAL

TORQUE MEASUREMENT AND INDICATING SYSTEM For training purposes only © Copyright - TURBOMECA



Training Notes

ARRIUS 1

TORQUE MEASUREMENT AND INDICATING SYSTEM DESCRIPTION - OPERATION Description

Operation

The hydraulic torquemeter includes:

In normal operation, the lubricating oil pump supplies the restrictor, which controls the torquemeter inlet pressure.

- A restrictor which controls the torquemeter oil inlet (lubricating oil pump pressure) - A stop - A piston linked to the intermediate gear through a ball bearing and a securing nut - An orifice which supplies the torque transmitter with modulated pressure (pressure which represents the torque). The torque transmitter includes:

This inlet pressure acts on the front face of the piston and balances the axial force F of the intermediate gear which has helical teeth (reaction changing with the load). The piston is fixed on the intermediate gear. Any gear axial movement determines a new balanced position of the piston by modifying the oil flow between the modulated pressure chamber and the piston chamber. The torque transmitter measures the modulated pressure and delivers an electrical signal to the torque indicator located in the cockpit.

- A resistive system which measures the modulated pressure provided by the torquemeter - An electrical connector which connects the transmitter to the torque indicator in the cockpit.




ARRIUS 1

Training Notes TORQUE INDICATOR

TORQUE TRANSMITTER

TORQUEMETER PISTON

From lubrication pump

OIL INLET RESTRICTOR

PISTON INTERMEDIATE GEAR

STOP

Modulated pressure (measured by the torque transmitter)

F

Axial force on the piston

Modulated flow according to torque C

DESCRIPTION - OPERATION




ARRIUS 1

Training Notes

TORQUE MEASUREMENT AND INDICATING SYSTEM TORQUE TRANSMITTER

Function


The transmitter transforms a modulated pressure into an electrical signal.

The transmitter contains a resistor bridge mounted on a deformable support. The pressure causes the variation of one of the resistor.

Position - In the system: downstream of the filter, after the torque pressure restrictor

The indicator supplies the reference input voltage (Ve). This voltage is fixed. The bridge provides an output voltage (Vs) of a few millivolts proportional to the oil pressure.

- On the engine: on the front face of the reduction gearbox casing.

Main characteristics - Type: resistive - Output signal: electrical voltage proportional to the torquemeter oil pressure - Output pressure (100% torque): 740 kPa (107.3 PSI) - Output voltage (100% torque): 370 mV.




ARRIUS 1

Training Notes

TORQUE TRANSMITTER

Type Resistive Output signal Electrical voltage proportional to the torquemeter oil pressure

TORQUE % 1 100

COCKPIT (to torque indicator)

Output pressure torque 100% 740 kPa (107.3 PSI) Output voltage torque 100% 370 mV

-

3 2

Ve Vs

+

-

4 5 740 kPa

Modulated pressure

+

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

TORQUE TRANSMITTER




ARRIUS 1

Training Notes

MISCELLANEOUS INDICATIONS INDICATORS

Indicator lights

Alphanumeric display

Some indicator lights provide indications of the engine operation.

The alphanumeric display is connected to the DCU.

The control panel includes the following indicating lights:

It displays some information in real or delayed time (refer to the following pages for more details).

- Chips - Min. oil pressure - Fire - Redundancy or min.or failure (amber GOV) - Training - Major failure (red GOV). The torque indicator includes the max. power warning light (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).




ARRIUS 1

Training Notes

CHIPS 1 AND 2

GOVERNOR

FIRE 1 AND 2

CONTROL PANEL

MAX. POWER WARNING LIGHT (torque, ∆N1, load factor)

TRAINING

MIN. OIL PRESSURE

GOVERNOR

0 2 1

ALPHANUMERIC DISPLAY

TORQUE INDICATOR

OEI 30 min. WARNING LIGHT

∆N1 INDICATOR

INDICATORS

MISCELLANEOUS INDICATIONS For training purposes only © Copyright - TURBOMECA



Training Notes

ARRIUS 1

MISCELLANEOUS INDICATIONS ∆N1 MEASUREMENT AND INDICATING SYSTEM

Function

Operation

The ∆N1 indicator displays the margin available in relation to the max. take-off power.

The DCU supplies the margin value between the actual power and the max. take-off power. The limit parameter is continuously calculated and corresponds to the zero value of the indicator.

It thus avoids permanent evaluation of the limit which must be respected.

- Aircraft cockpit.

The double indicator is graduated in percent. The margin between the indicator needle and the limit value represents the 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 following comparisons:

- Indicator graduated in percent

- Real N1-limit N1 (T/O N1), that is to say ∆N1.

- Signal supplied by the DCU.

- Real CH fuel flow-limit CH (T/O CH), that is to say ∆CH. The ∆CH is converted to ∆N1.

Position

Main components - Engine sensors

The DCU compares the two ∆N1 and sends to the indicator the nearest ∆N1 from the T/O limit or the one which exceeds this limit ("0" of the indicator).

- Digital Control Unit - Indicator.


Note: During power-up of the DCU, the indicator needle makes a partial sweep of the graduated scale.



ARRIUS 1

Training Notes

0 (T/O) (OEI 30')

(MCP)


∆N1 SIGNAL

(OEI 2'30") +4 ENGINE 1 AND 2 NEEDLES

-8 ∆N1 INDICATOR

T/O N1 (fP0, T1) ∆N1

REAL N1

∆N1 SIGNAL

T/O CH ∆N1

∆CH TO ∆N1 CONVERSION

∆CH

REAL CH DIGITAL CONTROL UNIT

∆N1 MEASUREMENT AND INDICATING SYSTEM




ARRIUS 1

Training Notes

MISCELLANEOUS INDICATIONS DISPLAY SYSTEM - GENERAL - DESCRIPTION

General

Control module

Function

It includes the following components:

The system displays parameters, operating status and failures.

- Mode selector • N1 mode • Failure mode • Memory mode • Parameter mode.

Main components Main components of the system:

- Control module

- Test selector • Test mode • Scroll mode.

- Digital Contol Unit

- Trim controls.

- Display unit

- Engine sensors.

Digital Control Unit

Description

RS 232 serial link.

Display unit

Engine sensors

It is an alphanumeric display with 5 digits, located in the cockpit.

Refer to the corresponding chapters.

In a twin-engine configuration, the display units of the two engines are located one above the other.




ARRIUS 1

Training Notes

ENGINE 1 ALPHANUMERIC DISPLAY ENGINE 2

SERIAL DATA LINKS

ENGINE 2 SENSORS ENGINE 1 SENSORS

ENGINE 2 DCU ENGINE 1 DCU

CONTROL MODULE Parameters N1

TEST

N1 TRIM NR ADJ

Failure Memory

SCROLL

DISPLAY SYSTEM - GENERAL - DESCRIPTION




ARRIUS 1

Training Notes

MISCELLANEOUS INDICATIONS DISPLAY SYSTEM - OPERATION The display unit has four operating modes: Ng, failure, memory, parameter.

"Parameter" mode

"N1" mode

This mode can be used on ground, engine stopped or running and during a test flight.

It is the normal mode in flight. The four digits, located on the right, display the gas generator speed (N1 or Ng) in tenths of one percent. The digit located on the left displays the letter "S" for overspeed arming. At power up, the letter "S" must extinguish at a speed of approx. 25% N2.

This mode helps in fault finding.

This mode displays the failure codes, the logic output and input status, the trim and sensor status in real time. Note: Refer to the maintenance manual for more information.

"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 NOVRAM type memory of the control module. Note: "Memory" mode is not available in flight (N1>20%)




ARRIUS 1

Training Notes

"N1" MODE

1 2

3

1 - Overspeed armed (switched off above 25% N2) 2 - BUS condition

"FAILURE" MODE CARB

Major failure

T1 P0 P COL TRIM P2 T4

Minor failures

ALIM Ng Np

3 - Ng speed (N1) OVSP OIL F E BUS

"MEMORY" MODE A …… B …… C ……

Last flight stored failures

OIL F DI T1 DI P0 E BUS Redundancy failures

Overspeed not armed Overspeed Oil filter Serial data link

"PARAMETER" MODE

Refer to the maintenance manual for more information.

Failures

D …… E …… F ……

Logic outputs

G …… H …… J ……

Logic inputs

L …………… α 0% M …………… α 1% N …………… T1°C P …………… P0 mb

MODE TABLE

DISPLAY SYSTEM - OPERATION




Training Notes

ARRIUS 1

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



STARTING

Training Notes

ARRIUS 1

STARTING SYSTEM - GENERAL DESCRIPTION Function

Description

The starting system ensures starting (on the ground and in flight) and ventilation of the engine. It includes the following functions: cranking, fuel supply, ignition, sequential control and indicating.

The system includes the following components:

Position All the starting accessories are installed on the engine except the Digital Control Unit which is installed in the aircraft. Indicating and control components, except the DCU, are supplied by the aircraft manufacturer.


- 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.

- 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 flight manual.



STARTING

ARRIUS 1

Training Notes

Starting envelope: Refer to Flight Manual

FUSES

Start duration: Approx. 30 sec. Dry crank time: Approx. 20 sec. max.

STOP-TRAINING-FLIGHT SELECTOR FLIGHT

Stabilisation time before shut-down: ≥ 60 seconds Max. gas temperature during starting: Refer to flight manual

STARTER CONTACTOR

STARTER

TRAINING STOP

DRY CRANK PUSH-BUTTON IGNITION SYSTEM

ACCESSORY RELAY

ROTOR BRAKE MICROSWITCH

START ELECTRO-VALVE

28V BUS BAR DCU

STOP ELECTRO-VALVE

0V LOGIC BUS BAR

COCKPIT COMPONENTS

ENGINE COMPONENTS

STARTING SYSTEM - GENERAL - DESCRIPTION For training purposes only © Copyright - TURBOMECA


STARTING

Training Notes

ARRIUS 1

STARTING SYSTEM - OPERATION This section deals with operating sequences associated with the starting system: starting, shut-down and dry crank.

Starting cycle The starting cycle is characterised by the evolution of the engine parameters and particularly the rotation speed and gas temperature.

Dry crank cycle A dry crank consists of cranking the rotating assembly without supplying fuel or ignition (dry ventilation). It is used for cooling the engine or for maintenance procedures. The dry crank cycle comprises the following phases: - Dry crank selection - Cranking of the rotating assembly

The main points of the starting cycle are:

- End of dry crank and run-down.

- Start selection - Self-sustaining speed (the starter and ignition system are 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.



STARTING

ARRIUS 1

Training Notes +

STARTER CONTACTOR

N1

Starter

Stabilisation at idle speed

DRY CRANK SELECTION

+

Stop selection

ACCESSORY RELAY

Starting accessories

Run-down

START SELECTION

DCU

N1 N2 100%

Flight

N2 92%

Training

Time

SHUT-DOWN CYCLE

t4.5 gas temperature

Dry crank cancel

N1

Self-sustaining speed

Selection Time

STARTING CYCLE

Selection

(20 sec. max.)

Time

DRY CRANK CYCLE

STARTING SYSTEM - OPERATION For training purposes only © Copyright - TURBOMECA


STARTING

Training Notes

ARRIUS 1

STARTER - GENERAL Function

Main components

The starter drives the gas generator rotating assembly within given conditions of torque and acceleration.

The main components of the starter are:

At the end of starting and when the rotation speed is sufficient, the starter operates as a generator.

The starter is located on the front face of the gearbox casing.

- Aircraft manufacturer's supply - Type: starter generator - Power supply: direct current on high intensity line.


- The mounting flange - The supply terminals.

Position


- The starter (starter and generator)

Interfaces - Electrical supply of the starter from the batteries through the starter contactor - Direct current supply to the aircraft circuit from the generator when the starting phase is completed - Drive of the gas generator rotating assembly through the accessory drive train.


STARTING

ARRIUS 1

Training Notes

Aircraft electrical system

SUPPLY BUS BAR

Direct current STARTER

+VDC STARTER CONTACTOR

ELECTRICAL INTERFACE Aircraft manufacturer's supply

DRIVE OF THE GAS GENERATOR ROTATING ASSEMBLY

Type Starter generator Power supply Direct current on high intensity line

STARTER


MECHANICAL INTERFACE

STARTER - GENERAL For training purposes only © Copyright - TURBOMECA


STARTING

Training Notes

ARRIUS 1

STARTER - DESCRIPTION - OPERATION The starter includes the following components:

Engine cranking

- Supply terminals • Excitation • Generator • Negative terminal (-) • Starter • Balancing.

When the start is selected (in the cockpit), the starter contactor closes and allows the direct current supply of the starter through the aircraft supply bus bar. The electrical motor of the starter then provides the torque required to crank the gas generator. The cranking torque is inversely proportional to the gas generator rotation speed. The torque increases when the atmospheric temperature decreases.

- Casing (starter frame) - Mounting flange on gearbox casing

The gas generator rotation speed increases up to a self sustaining speed (50% N1). At a speed of 50%, the torque becomes negative and the electrical supply to the starter motor is cut (opening of the starter contactor).

- Brushes - Windings (stator and rotor) - Fan - Splined shaft

Electrical generator

- Commutator.

When starting is completed (N1 > 50%), the electrical supply to the starter motor is cut, but the starter is mechanically driven by the gas generator through the accessory drive train. The starter then operates as an electrical DC generator and supplies the aircraft electrical system.

Operation The starter ensures: - The engine cranking during starting - The electrical supply to the aircraft electrical system at the end of the starting phase.



STARTING

ARRIUS 1

Training Notes MOUNTING FLANGE (on reduction gearbox casing)

CASING

BRUSHES STARTING TORQUE COOLING FAN DECREASING ATMOSPHERIC TEMPERATURE

50% 0 SPLINED SHAFT

WINDINGS (stator and rotor)

N1

SELF-SUSTAINING SPEED

COMMUTATOR

STARTER

GENERATOR

COOLING AIR -

SUPPLY TERMINALS +D

Generator (+G) Starter (+D) Negative Balancing (Eq) Excitation (Ex) terminal

+G Eq Ex

+ VDC +

AIRCRAFT SYSTEM ELECTRICAL SUPPLY

ELECTRICAL CURRENT GENERATION

STARTER - DESCRIPTION - OPERATION For training purposes only © Copyright - TURBOMECA


STARTING

Training Notes

ARRIUS 1

IGNITION SYSTEM Function

Main components

This system ensures the ignition of the fuel sprayed by the start injectors into the combustion chamber.

- Ignition unit

Position

- Igniter plugs.

- All the ignition system components are installed on the engine except the electrical supply circuit.

Note: Refer to the following pages for the description and the operation of the ignition system components.

- Ignition cables

Main characteristics - Type: High Energy (HE) - Electrical power supply: 10 to 32 VDC.



STARTING

ARRIUS 1

Training Notes

Starter contactor

M control relay

Starter

PP8 bus Ignition cables

Igniter plugs

PP21 bus High Energy ignition unit Type High Energy (HE)

M

Electrical power supply 10 to 32 VDC

IGNITION SYSTEM For training purposes only © Copyright - TURBOMECA


STARTING

Training Notes

ARRIUS 1

IGNITION SYSTEM IGNITION UNIT

Function

Operation

The ignition unit transforms the DC voltage provided by the aircraft circuit into high energy voltage required to operate the igniter plugs.

The ignition unit operation is characterised by an accumulation phase of the electrical loads and a quick discharge phase.

Position

The ignition unit is supplied with 28 V, it changes this to a high energy voltage (3 kVolts).

The unit is installed on the upper right part of the air intake plenum (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 igniter plugs.



STARTING

ARRIUS 1

Training Notes

HIGH ENERGY IGNITION UNIT

OUTPUT ELECTRICAL CONNECTORS (High Energy current)

Type High Energy, sealed case

INPUT ELECTRICAL CONNECTOR (direct current)

CABLES (to igniter plugs)

IGNITION UNIT



STARTING

Training Notes

ARRIUS 1

IGNITION SYSTEM IGNITER PLUGS

Function

Description

The two igniter plugs ignite the fuel/air mixture sprayed by the start injectors during starting. Two cables connect the igniter plugs to the ignition unit.

An igniter plug includes:

- An insulator

Position - The igniter plugs are installed beside two start injectors. They are located at the rear of the combustion chamber on each side of the engine (at 11 o'clock and 5 o'clock).

- A central electrode connected to the positive terminal - A semi-conductor.

Operation

Main characteristics - Type: High Energy, surface discharge (semi-conductor surface coating) - Quantity: 2.

- An external body connected to the negative terminal

When the high energy current produced by the ignition unit is discharged to the igniter plug, the voltage applied between the central electrode and the external body produces a powerful spark. This spark ignites the fuel/air mixture sprayed into the combustion chamber by the two start injectors.



STARTING

ARRIUS 1

Training Notes MOUNTING FLANGE SEALS

ELECTRICAL CONNECTOR (to ignition unit)

SLEEVE IGNITER PLUG

INSULATOR EXTERNAL BODY (-) Type High Energy Semi-conductor IGNITER PLUG

Quantity 2 Engine rear face

Spark

CENTRAL ELECTRODE (+)

SEMICONDUCTOR

IGNITER PLUGS



STARTING

Training Notes

ARRIUS 1

IGNITION SYSTEM IGNITION CABLES

Function

Description

The ignition cables supply the high energy current (produced by the ignition unit) to the igniter plugs.

One ignition cable includes: - A nickel-plated copper multicore

Position - Between the ignition unit and the igniter plugs.

- An outer shielding (stainless steel braid) - Two inner shields (silver-plated copper braid)


- Two stainless steel rigid end fittings

- Type: multi-core nickel-plated copper wire

- Two electrical connectors • One igniter plug connector (ceramic insulator, spring and nut) • One ignition unit connector (teflon insulator, silicone joint, spring and nut).

- Quantity: 2 identical independent cables - Shielding: triple braided.



STARTING

Training Notes

ELECTRICAL CONNECTOR (connection with the igniter plug)

ARRIUS 1 ELECTRICAL CONNECTOR (connection with the ignition unit)

Type Multi-core nickel-plated copper wire Quantity 2 identical and independent cables Shielding Triple braided

IGNITION CABLE (wire and shield)

IGNITION CABLES



STARTING

ARRIUS 1

Training Notes

10 - ELECTRICAL SYSTEM - Electrical system ................................................ 10.2 - Alternator ........................................................... 10.4 - Electrical harnesses (77-30-02) .......................... 10.6 to 10.7



ELECTRICAL SYSTEM

ARRIUS 1

Training Notes

ELECTRICAL SYSTEM Function

Main components

The system contributes to the various indicating and control functions of the engine:

- Engine electrical components (control components and sensors)

- Control

- Control and indicating components

- Control system

- Digital Control Unit (installed in the airframe)

- Safety system

- Electrical harnesses.

- Maintenance aid.

Main characteristics - Direct current: 28 VDC from aircraft electrical system - Dedicated alternator electrical power: 100 VA.



ELECTRICAL SYSTEM

Training Notes

CONTROL AND INDICATING COMPONENTS

ARRIUS 1

Direct current: 28 VDC from aircraft electrical system Dedicated alternator electrical power: 100 VA

ACCESSORIES AND SENSORS ELECTRICAL HARNESSES


ELECTRICAL SYSTEM For training purposes only © Copyright - TURBOMECA


ELECTRICAL SYSTEM

Training Notes

ARRIUS 1

ALTERNATOR Function

Operation

The altenator is dedicated to the Digital Control Unit electrical supply.

The three-phase voltage produced by the alternator is sent to the Digital Control Unit

Position

An electrical connector connects the alternator to the Digital Control Unit and is protected by a fuse.

- On the engine: on the front face of the reduction gearbox. DCU power supply


The DCU is electrically supplied either from the 28 V aircraft supply (J2 connector) or from the engine alternator (J1 connector) as follows.

- Type: Three-phase, continuous operation - Power: 100 VA

- The 28 V aircraft supply is used alone: • During starting • In case of an alternator failure during flight.

- Output voltage: 28 to 63 Volts.

Main components - The alternator is used during flight (normal operation) - Drive shaft - The alternator is used alone in case of 28 V aircraft supply failure during flight.

- 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 by the same shaft.



ELECTRICAL SYSTEM

ARRIUS 1

Training Notes ELECTRICAL CONNECTOR (to DCU)

ALTERNATOR

Type Three-phase, continuous operation Power 100 VA Output voltage 28 to 63 Volts LP PUMP

DIGITAL CONTROL UNIT SUPPLY PRINCIPLE

N1 0%

50%

100% STATOR

Normal operation

Aircraft supply

28V network aircraft failure

Alternator failure

Alternator

U +

Alternator

Aircraft supply

Aircraft supply

FUSE (in the alternator connector)

INSIDE THE DCU

ALTERNATOR For training purposes only © Copyright - TURBOMECA


ELECTRICAL SYSTEM

Training Notes

ARRIUS 1

ELECTRICAL HARNESSES Function


The harnesses connect the electrical accessories to the DCU and the aircraft circuit.

The engine electrical harness connects the engine to the aircraft systems.


Two electrical plugs connect the engine accessories to the DCU J1 and J5 plugs through the P1 and P5 connectors.

- Cable type: plaited, shielded or overshielded

The third plug connects the engine to the aircraft controls, indicators and indicating lights.

- Connector type: screw-in connectors.

Main components The main electrical harnesses connect: - The engine to the aircraft controls, indicators and indicating 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 (twinengine configuration).



ELECTRICAL SYSTEM

ARRIUS 1

Training Notes

AIR TEMPERATURE PROBE AIRCRAFT/ENGINE CONNECTION

P5 CONNECTOR

P1 CONNECTOR

DCU / ENGINE CONNECTION

ELECTRICAL HARNESSES For training purposes only © Copyright - TURBOMECA


ELECTRICAL SYSTEM

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



ENGINE INSTALLATION

ARRIUS 1

Training Notes

ENGINE COMPARTMENT Function

- Removable cowlings which allow access to the engines

The helicopter engine compartment houses the engines and ensures their ventilation.

- A support platform fitted with engine support fittings.

Engine compartment ventilation Position The engine compartment is ventilated by atmospheric air in order to limit the temperature in different engine areas.

- At the rear of the helicopter main gearbox.

The atmospheric air circulation through the compartment is ensured by ventilation scoops located on each side of the removable cowling. The air is accelerated by the venturi extension of the exhaust system.

Description Each engine compartment includes: - Three fire walls which ensure sealing and protection in case of fire: • One firewall is located in front of the engine (between the 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 engine compartment, which mainly includes: • The engine air intake • An oil cooler air outlet • Compartment ventilation scoops…



ENGINE INSTALLATION

ARRIUS 1

Training Notes ENGINE COMPARTMENTS

REMOVABLE COWLING - Engine air intake - Oil cooler air outlet - Compartment ventilation scoops

REMOVABLE COWLING

FIREWALL (separation of the engine compartments)

ENGINE

ENGINE

FRONT FIREWALL

REAR FIREWALL

SUPPORT PLATFORM (fitted with the engine support fittings)

ENGINE COMPARTMENT For training purposes only © Copyright - TURBOMECA


ENGINE INSTALLATION

ARRIUS 1

Training Notes

ENGINE MOUNTING AND LIFTING Engine mounting

Engine lifting

Function

Function

The engine mountings attach the engine to the airframe.

The lifting rings permit engine lifting.

Description

Description

- Front support: circular flange fitted with nine studs

- At the front: one ring fitted on the gearbox casing flange

- Rear support: bracket fitted on the underside of the gearbox casing.

- At the rear: two rings fitted on the compressor casing flange. Engine removal and installation Turbomeca provides an engine lifting sling which attaches to the lifting rings on the engine. This permits the removal and installation of the engine in the airframe. The removal/installation procedure is described in the airframe maintenance manual and must only be carried out in accordance with this procedure, using the appropriate tool.



ENGINE INSTALLATION

ARRIUS 1

Training Notes

REAR LIFTING RINGS

FRONT LIFTING RING

LIFTING SLING

TRANSPORT ATTACHMENT

ENGINE SUPPORT BRACKETS (on engine stand)

REAR ATTACHMENT

FRONT ATTACHMENT

REAR ATTACHMENT

ENGINE STAND

ENGINE MOUNTING AND LIFTING For training purposes only © Copyright - TURBOMECA


ENGINE INSTALLATION

Training Notes

ARRIUS 1

POWER DRIVE Function

Helicopter main gearbox - engine transmission

The engine power drive provides the mechanical power required to drive the helicopter main gearbox.

The link to the helicopter main gearbox is ensured by: - A flexible coupling installed on the triangular flange

Position

- A transmission shaft

- The power drive is located at the front lower part of the gearbox casing.

- A helicopter coupling which links the transmission shaft to the helicopter main gearbox.


Note: The transmission system is supplied by the aircraft manufacturer.

- Mechanical power: 350 kW (470 HP) - Rotation speed: 6016 RPM (100% N2); CW.

Description The power drive includes a triangular flange which is splined onto the output gear and secured by a nut. The triangular flange has three bolt holes. Power drive sealing is ensured by a graphite seal installed around a ring which is fitted on the output shaft. The power drive casing also has a drain which expels any oil leaks.



ENGINE INSTALLATION

ARRIUS 1

Training Notes

HELICOPTER MAIN GEARBOX

TRANSMISSION SHAFT

HELICOPTER COUPLING

POWER DRIVE (triangular flange)

FLEXIBLE COUPLING

POWER REDUCTION GEAR DRIVE OUTPUT SHAFT (triangular flange)

ROLLER BEARING

REDUCTION GEAR OUTPUT GEAR

SECURING NUT

DRAIN

GRAPHITE SEAL

RING

POWER DRIVE For training purposes only © Copyright - TURBOMECA


ENGINE INSTALLATION

Training Notes

ARRIUS 1

AIR INTAKE Function


The air intake system collects and guides the ambient air into the engine.

The air intake system includes the following components :

Position - On each side of the helicopter, at the rear of the main gearbox.

Main characteristics - Lateral air intake on aircraft and annular air supply for each engine (plenum chamber).


- Air intake duct. Supplied by the aircraft manufacturer, it comprises 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 to chapter "ENGINE"). A compressor cleaning connection can be installed on the intake and a vibration sensor support is installed permanently.


ENGINE INSTALLATION

ARRIUS 1

Training Notes

AIR INTAKE PLENUM

AIR INTAKE GUARD

AIR INTAKE DUCT

ENGINE AIR INTAKE CASING

AIR INTAKE For training purposes only © Copyright - TURBOMECA


ENGINE INSTALLATION

Training Notes

ARRIUS 1

EXHAUST SYSTEM Function

Main components

The exhaust system discharges the exhaust gas overboard.

- Engine exhaust pipe

Position

- Exhaust extension.

- At the rear of the engine.



The gases pass from the engine exhaust to the extension which directs the gases overboard through the cowling passage.

- Type: axial, exhaust pipe with extension - Replaceable non modular component.

Air is drawn from the engine compartment by the venturi effect between the extension and the exhaust pipe thus ensuring compartment ventilation. The oil system vent pipe is connected to a mounting on top of the exhaust pipe.



ENGINE INSTALLATION

Training Notes

Oil system vent line

ARRIUS 1

Engine compartment air suction by venturi effect

POWER TURBINE

GAS EXHAUST

EXHAUST PIPE

EXTENSION

EXHAUST SYSTEM For training purposes only © Copyright - TURBOMECA


ENGINE INSTALLATION

Training Notes

ARRIUS 1

DRAIN SYSTEM Function

Power drive drain

The drain system collects the various drains and any leaks from the engine.

This drain will collect any leaks from the power drive. There are in fact two orifices, one on each side of the support.

Engine drains

Fuel valve assembly support drain

LP fuel pump drive drain It is a dry drain which will collect any leaks between the two seals of the alternator/LP pump drive shaft

The fuel valve assembly is mounted on a dished steel plate which is equipped with a drain pipe at each side at the rear. Any fuel leaks from the fuel valve will be discharged overboard via these drain pipes.

HP fuel pump unit drain It is a dry drain which will collect: - Any fuel which leaks between the two seals installed on the HP pump drive shaft - Any fuel which leaks from the fuel metering unit. Combustion chamber drain The combustion drain valve drains the residual fuel during engine shut-down and during starting.



ENGINE INSTALLATION

Training Notes

ARRIUS 1

LP FUEL PUMP DRIVE DRAIN

FUEL VALVE ASSEMBLY DRAIN

COMBUSTION CHAMBER DRAIN

POWER DRIVE DRAIN

HP FUEL PUMP UNIT AND METERING UNIT DRAIN

DRAIN SYSTEM For training purposes only © Copyright - TURBOMECA


ENGINE INSTALLATION

Training Notes

ARRIUS 1

FIRE PROTECTION Fire detection

Description

Function

The system includes:

The fire detection system detects overtemperature in the engine compartment and gives a cockpit indication.

- On the engine: detectors and electrical wiring

Position

- In the aircraft: indicating lights, fire detection unit, test selector and extinguishing system (aircraft manufacturer's supply).

- In the system: connected to the cockpit Fire detectors - On the engine: • "Cold" zone: one detector located on the upper part of the gearbox mounting flange and one detector located on the LP fuel pump/alternator assembly, • "Hot" zone: one detector located on the lower part of the rear bearing casing and one detector located above the oil inlet union of the rear bearing. Main characteristics - "Cold" zone: • Detector setting: nominal value: 200°C (392°F), • Quantity: 2

Each fire detector includes a bi-metallic strip which opens the electrical circuit in case of overheat. It is fitted with a resistance in parallel which enables the system to differentiate between the normal opening of a detector and a wiring defect.

Extinguishing system The fire extinguishing system includes an extinguisher bottle and spraying jets. The extinguishing system can be operated from the cockpit (system supplied by the aircraft manufacturer). Note: Refer to the aircraft manual for more information on the extinguishing system.

- "Hot" zone: • Detector setting: nominal value: 400°C (752°F), • Quantity: 2



ENGINE INSTALLATION

ARRIUS 1

Training Notes

MECHANICAL STOP MOUNTING FLANGE

Cold zone

Hot zone Aircraft

UNINSULATED BI-METALLIC STRIP

Engine

+ Alarm

Detection

INSULATED BI-METALLIC STRIP

FIRE DETECTOR

logic + Test button

+ Extinguishing button

Note: Refer to the aircraft manual for more information on the extinguishing system.

"COLD" ZONE

"HOT" ZONE:

Detector setting: Nominal value: 200°C (392°F)

Detector setting: Nominal value: 400°C (752°F)

Quantity: 2

Quantity: 2

FIRE PROTECTION For training purposes only © Copyright - TURBOMECA


ENGINE INSTALLATION

ARRIUS 1

Training Notes

12 - OPERATING LIMITATIONS AND PROCEDURES - Operating limitations ......................................... 12.2 - Operating procedures ........................................ 12.4 to 12.7



OPERATING LIMITATIONS AND PROCEDURES

Training Notes

ARRIUS 1

OPERATING LIMITATIONS All operating limitations are defined in the official documents: - 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

FLI

GH

TM

AN U

AL

ENGINE AND SYSTEM LIMITATIONS -

Flight envelope Gas generator rotation speed Power turbine rotation speed Turbine entry gas temperature Torque Miscellaneous (load factors, vibration...) - Pressure, flow, volume, voltage...

L

NUA

MA

EN

INT

MA

E ANC

OPERATING LIMITATIONS For training purposes only © Copyright - TURBOMECA



ARRIUS 1

Training Notes

OPERATING PROCEDURES (1) The operating procedures are considered for training purposes only. It is mandatory to refer to the aircraft manual.

Preparation before starting

Note: To start a cold engine with a low ambient temperature, the oil temperature must increase before any load is applied.

- Inspection, checks…

In flight engine control

Starting

- Normal automatic procedure: before the engine powerup, check the oil temperature

Start procedures:

- The control unit adapts the engine to the flight conditions (control): check the indicating lights and monitor the engine parameters (N1, N2, gas temperature, torque, oil pressure and temperature)

- 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 to accelerate 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.


- "Trim" action if necessary: check the effect on NR (rotor speed) or engine matching.

Engine shut-down - Stabilisation: minimum collective pitch (stabilisation of 60 seconds at least) - FLIGHT-TRAINING-STOP selector on STOP position: check the parameters and the rundown time.



ARRIUS 1

Training Notes

The operating procedures are considered for training purposes only. It is mandatory to refer to the aircraft manual.

STARTING - Electrical system power on - Booster pump on - Selector actuation (direct selection of the "Flight" position possible) - Checks

PRE-START CHECKS - Inspections, checks…

ENGINE SHUT-DOWN

IN FLIGHT ENGINE CONTROL

- Minimum collective pitch - Stabilisation (approx. 60 sec.) - Selector on "Stop" position - Check…

- Normal automatic procedure - Engine adaptation to the flight conditions (control system) - "Trim" action if necessary

NORMAL PROCEDURES

OPERATING PROCEDURES (1) For training purposes only © Copyright - TURBOMECA



ARRIUS 1

Training Notes

OPERATING PROCEDURES (2) Particular procedures.

Manual control in flight

Relight

- Manual control of the metering valve (after a failure or controlled "freezing")

The relight procedure is the same as the ground start procedure. However, the N1 rotation speed must be lower than 17% (automatic interlock).

- Move the lever in the + or - range to alter the fuel flow

Engine ventilation

- Check the engine parameters. Caution

- FLIGHT-TRAINING-STOP selector on STOP position - Depress the Dry crank push-button - Check the N1 speed.

Do not move the lever down below the reduction notch in order to prevent flame out.

Special procedures (flame out, fire, failures…)

Note: No more than 20 seconds. Refer to flight manual.

Training procedures - Automatic training operating procedure: only with a reduced load helicopter; the operating engine limitations are derated and the other engine is set to the idle rating (N2)

Note: The operating procedures are considered for training purposes only. It is mandatory to refer to the aircraft manual.

- Manual mode: the main metering valve is "frozen". Allows training for a major failure or manual control. Return to automatic is possible without restriction.




ARRIUS 1

Training Notes

The operating procedures are considered for training purposes only. It is mandatory to refer to the aircraft manual.

DRY CRANK

RELIGHT

- Selector on "Stop" position - Dry crank push-button actuated - Check the N1 speed

- Same procedure as for the ground start procedure - Wait for N1 < 17%

Note:

20 sec. max.

TRAINING PROCEDURES MANUAL CONTROL IN FLIGHT - Automatic training operating procedure - Manual mode: allows training for a major failure

- Metering valve manual control - Move the lever in the + or - range - Check the engine parameters

PARTICULAR PROCEDURES

OPERATING PROCEDURES (2) For training purposes only © Copyright - TURBOMECA



ARRIUS 1

Training Notes

13 - VARIOUS ASPECTS OF MAINTENANCE - Maintenance concept .................................................... - Life limitation ................................................................ - Preventive maintenance ................................................ - "On-condition" monitoring .......................................... - Corrective maintenance ................................................ - Technical publications ..................................................


13.2 13.4 13.6 13.8 13.10 13.12 to 13.15


VARIOUS ASPECTS OF MAINTENANCE

ARRIUS 1

Training Notes

MAINTENANCE CONCEPT

Second line maintenance: engine maintenance in shop (I level).

Introduction

- Corrective maintenance: SRU and module removal and installation.

The engine is designed to have a high availability rate with reduced maintenance.

Third line maintenance: deep maintenance which involves module repairs (H level).

The main aspects of the maintenance concept are the following:

- Corrective maintenance: component replacement.

- Effective modularity

Fourth line maintenance: overhaul and repair in specific shop (D level).

- Good accessibility

- Maintenance scheduled when the TBO is completed or when the life limit of a component is reached - Corrective maintenance.

- Reduced removal and installation times - On-condition facility - Quick repair.

Other aspects of maintenance

Maintenance levels

Refer to the following pages.

Four maintenance levels can be considered:

Note 1:

SRU - Shop Replaceable Unit.

First line maintenance: engine installed on the aircraft (O level). - Scheduled and preventive maintenance: • Checks and inspections • Life limit or completed TBO removal

Note 2:

The maintenance steps are determined by the operator taking into account the difficulties, the personnel and logistic considerations. As far as the engine manufacturer is concerned, the current maintenance procedures (1st, 2nd line) are defined and described in the maintenance manual. Deep maintenance (3rd line) and general overhaul (4 th line) are described in other documents and are subject to particular license agreements.

- Corrective maintenance: • Fault detection • Component replacement (LRU) • Check


LRU - Line Replaceable Unit



Training Notes

ARRIUS 1

MAINTENANCE LEVELS

1st LINE MAINTENANCE (O level) (engine installed on aircraft) - Scheduled or preventive maintenance - Corrective maintenance

2nd LINE MAINTENANCE (I level) (engine removed) - Corrective maintenance (modules, SRU)

Maintenance Manual

3rd LINE MAINTENANCE (H level) (engine removed) - Deep maintenance

4th LINE MAINTENANCE (D level) (engine removed in specific shop) - Scheduled maintenance (overhaul, repair) - Corrective maintenance

Maintenance Technical Instruction

Overhaul Manual

MAINTENANCE CONCEPT For training purposes only © Copyright - TURBOMECA



Training Notes

ARRIUS 1

LIFE LIMITATION TBOs

Calendar limits

TBOs (Time Between Overhauls) are defined for the engine, the modules and some accessories. These TBOs, determined by tests and experience, are subject to an extension programme. The TBO is expressed in operating hours.

The calendar limit is the time (expressed in years) after which the complete engine, modules or parts subjected to calendar limit has to be returned to the factory or an approved repair center.

Life-limited parts Certain components (mainly rotating parts such as compressor, turbines, …) have a life limit which requires the part to be scrapped when the limit is reached. This limit is calculated in hours and/or cycles. A cycle is a clearly defined operating sequence. The first limit achieved necessitates their replacement by a deep maintenance procedure or by a TURBOMECA agreed repair centre. A list of these parts is given in Chapter 5 of the Engine Maintenance Manual, and in Section D of the engine log book.

Counting of hours and cycles Cycle counting is effected either manually or automatically. The method of counting cycles and the various limits are described in Chapter 5 of the maintenance manual. A counting check (comparison between automatic counting and manual counting) is a procedure planned in the periodic maintenance. A simple check can be carried out by comparing the two engine readings for a given period of operation.


The count starts at the engine first installation in the aircraft (since new, overhaul or repair).

"On-condition" Some components have no TBO, no life limit, no calendar limits. They are generally considered as "on-condition".

Use-limited parts These parts have a maximum usage defined in hours; this includes parts such as bearings, casings and shafts. Their limits are greater than the normal TBO of the engine, thus permitting them to be used for two or more TBOs, which reduce engine overhaul costs for the customer. These parts and their corresponding limits are listed in section D of the engine log book.



ARRIUS 1

Training Notes

CALENDAR LIMITS

TBOs

Time limits (since new, overhaul or repair): - Engine - Modules - Parts

- Engine - Modules - Accessories

LIFE-LIMITED PARTS "ON-CONDITION"

First limit reached: - Operating hours and/or - Operating cycles

Some components have no TBO, no life limit, no calendar limits. They are generally considered as "on-condition".

Cycles for: - Compressors - Turbines - ...

USE-LIMITED PARTS Maximum usage: - Defined in hours - Greater than the normal TBO Usable for two or more TBOs, which reduce engine overhaul costs

COUNTING OF HOURS AND CYCLES - Manual counting - Automatic counting - Counting check

Electronic Control Unit

Display in the cockpit AUTOMATIC COUNTING

LIFE LIMITATION For training purposes only © Copyright - TURBOMECA



Training Notes

PREVENTIVE MAINTENANCE Preventive maintenance includes the procedures which must be systematically carried out and the procedures which 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 are distributed over a period of time to reduce the turnaround time 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 to comply with airworthiness objectives. They are listed, along with their associated frequencies, in the table of mandatory maintenance tasks. These mandatory maintenance tasks and/or their associated frequencies can only be modified with the prior approval of the EASA (European Aviation Safety Agency) and TURBOMECA. For training purposes only © Copyright - TURBOMECA

ARRIUS 1

- Obligatory maintenance tasks. TURBOMECA considers that obligatory maintenance tasks must be performed at the frequencies specified. These obligatory maintenance tasks and/or their associated frequencies can be adapted with the prior approval of TURBOMECA and the Regulatory Authorities. - Optional maintenance tasks. Turbomeca advises that optional maintenance tasks be performed at the frequencies specified in order to improve reliability and operational availability, and in order to reduce engine operating costs. These optional maintenance tasks and/or their associated frequencies can be adapted with the prior approval of TURBOMECA, subject to compliance with the regulations of the local Regulatory Authorities. Mandatory maintenance tasks are listed in the "Airworthiness Limitations" section of the Maintenance Manuals. Obligatory and optional maintenance tasks are listed 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.



ARRIUS 1

Training Notes

SERVICING INSPECTIONS - Inspection "before the first flight of the day" - Inspection "after the last flight of the day" - Inspection... (according to engine type)

REFER TO THE MAINTENANCE MANUAL Chapter 05

PERIODIC INSPECTIONS - Procedures "blocked" or "staggered" (flight hours or calendar schedule) - Special inspections

- Mandatory - Obligatory - Optional

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

PREVENTIVE MAINTENANCE For training purposes only © Copyright - TURBOMECA



Training Notes

ARRIUS 1

"ON-CONDITION" MONITORING When applying on-condition maintenance, the maintenance procedures are carried out according to the condition of engine components. It requires a monitoring which includes appropriate procedures studied during the engine design.

Objectives of on-condition monitoring The objective is to increase safety and to reduce maintenance costs. This is obtained as the monitoring ensures an early diagnosis of anomalies which could have serious consequences; on the other hand, monitoring avoids unnecessary maintenance tasks.

On-condition monitoring resources On-condition monitoring implies an appropriate design of the engine which allows the use of monitoring tools. The following procedures are available:

- Lubrication oil check: various methods are used to check for the contamination of the oil (magnetic plugs, strainers sampling). Samples of oil are taken at regular intervals and the samples are analysed to measure the contamination and anticipate incipient failures (analysis by magnetoscopy, ferrography, spectrometric oil analysis) - Vibration level check: the vibration level of the rotating assemblies gives an indication of the engine condition. Sensors installed at given points are used to measure the vibration level. This type of check is carried out during periodic inspections or according to engine condition - Power check: the monitoring is ensured by means of the Electronic Control Unit (refer to "CONTROL SYSTEM" chapter and Flight Manual) - Visual inspection: conventional visual inspections are also considered for on-condition monitoring (air intake inspection, exhaust pipe inspection, exhaust and engine external inspections…).

- Borescopic inspection: this permits inspection of internal parts which are not accessible without disassembly: compressor, combustion chamber and turbine. A special tool is used to allow direct visual inspection of the parts




ARRIUS 1

Training Notes

OBJECTIVES OF ON-CONDITION MONITORING - To increase safety - To reduce maintenance costs

BORESCOPIC INSPECTION POWER CHECK

VIBRATION CHECK

VISUAL INSPECTION

LUBRICATION OIL CHECK

"ON-CONDITION" MONITORING For training purposes only © Copyright - TURBOMECA



Training Notes

ARRIUS 1

CORRECTIVE MAINTENANCE Objective of corrective maintenance The objective is to put the engine back into normal service as soon as possible. Corrective maintenance includes all procedures 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 Trouble Shooting Manual: chapter 71) - Functional checks - Condition checks - Removal and installation: removal and installation of the complete power plant, of the accessories and of the modules and of some engine components as required. Note: Assembly and disassembly of the engine is dealt with in general overhaul and repair. - Adjustments - Miscellaneous procedures: cleaning, storage… - Repair or replacement - Particular instructions: for example, procedures in the event of oil contamination, surge, heavy landing, handling accident, lightning...




ARRIUS 1

Training Notes

OBJECTIVE OF CORRECTIVE MAINTENANCE - To put the engine back into normal service as soon as possible

CORRECTIVE MAINTENANCE MAIN TASKS - Fault finding - Functional and condition checks - Removal and installation - Adjustments - Miscellaneous procedures (cleaning, storage ...) - Repair (or replacement) - Particular instructions

CORRECTIVE MAINTENANCE For training purposes only © Copyright - TURBOMECA



ARRIUS 1

Training Notes

TECHNICAL PUBLICATIONS - GENERAL This part deals with the engine technical documentation.

Operation documents The operation documents are:

- The general overhaul and repair documents (4th line): • Overhaul manual • Standard practices manual • Work specification.

- The control documents (e.g.: flight manual)

Identification documents

- The management documents: • Engine log book (records and provides information on the engine status).

The identification documents are:

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, and issued to inform the operators of a modification or an instruction which affects the operational aspects) • Service letters (letter sent to inform the operator of certain instructions related to the operation of the engine) • Modification index

- 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 general overhaul) • 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.

- The deep maintenance instructions (3rd line): • Maintenance technical instructions




ARRIUS 1

Training Notes

DOCUMENTS

MAINTENANCE

OPERATION

CONTROL

Example: Flight manual

CURRENT MAINTENANCE

MANAGEMENT

Example: Engine log book

CURRENT MAINTENANCE (1st and 2nd lines)

- Maintenance manual - Service bulletins and letters - Modification index

IDENTIFICATION

- Spare parts catalogue - Special tool catalogue

DEEP MAINTENANCE (3rd line)

Maintenance technical instructions

OVERHAUL REPAIR

- IPC - Descriptive list and drawings

GENERAL OVERHAUL REPAIR (4th line)

- Overhaul manual - Standard practices manual - Work specification

TECHNICAL PUBLICATIONS - GENERAL For training purposes only © Copyright - TURBOMECA



Training Notes

ARRIUS 1

TECHNICAL PUBLICATIONS - ADVISORY NOTICES Three types of advisory notice are used in the technical publications: - WARNING

Examples WARNING: do not breath the oil fumes. Do not leave oil in contact with the skin. CAUTION: if the flush is being carried out because of metal particles in the oil system, change the filter and thoroughly clean the tank.

- CAUTION - NOTE.

NOTE: take the oil sample before carrying out any replenishment.

Interpretation WARNING: warns the reader of the possibility of physical harm (e.g.: wounding, intoxication, electrocution). CAUTION: warns the reader of the possibility of damaging the engine or tooling. NOTE: gives the reader advice on how best to carry out a task.




ARRIUS 1

Training Notes

WARNING (physical harm)

CAUTION (possibility of damage)

NOTE (advice)

Examples:

Examples:

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 - ……

- Titanium part cleaning - Scrapping of O'ring seals - Use of the correct cleaning products - Engine cooling - Engine cleaning after use of extinguishing product - Orifice protection during removal - Borescope fragility - Tightening torque - ……

- Oil analysis - Cycle counting - Installation of O'ring seals - Engine storage - Insulation measurements - Procedural change with modification - ……

TECHNICAL PUBLICATIONS - ADVISORY NOTICES For training purposes only © Copyright - TURBOMECA



ARRIUS 1

Training Notes

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.



MAINTENANCE PROCEDURES

ARRIUS 1

Training Notes

MAINTENANCE PROCEDURES - GENERAL This part is an introduction to the different maintenance procedures, which are described in the following pages for training purposes only.

- Engine removal and installation

These procedures are dealt with in discussion and practical work during a training course.

- Module removal and installation

Procedures

Note: It is mandatory to refer to refer to the approved and current TURBOMECA maintenance technical publications to carry out any maintenance procedure.

- Definition - Instructions and operating modes

- Removal and installation of the accessories

- Repair, general overhaul.

List of procedures - Standard practices - Cautions - Washing - Miscellaneous checks - Miscellaneous procedures - Removal, installation - Repair - Adjustments - ...




ARRIUS 1

Training Notes

LIST OF PROCEDURES

PROCEDURES

- Standard practices - Cautions - Washing - Miscellaneous checks - Miscellaneous procedures - Removal, installation - Repair - Adjustments -…

- Definition - Instructions and operating modes

It is mandatory to refer to the approved and current TURBOMECA maintenance technical publications to carry out any maintenance procedure.

MAINTENANCE PROCEDURES - GENERAL For training purposes only © Copyright - TURBOMECA



ARRIUS 1

Training Notes

1ST LINE MAINTENANCE PROCEDURES (O LEVEL) The 1st line maintenance procedures are described in the Maintenance Manual and can be carried out on the engine installed, in the airframe. They include:

Consumable or repairable components The accessories are considered as either consumable or repairable.

- Preventive maintenance procedures

Some accessories which are considered as consumable: fire detectors, start injector, igniter plug, ignition unit, speed sensors, filters, strainers, magnetic plug…

- Corrective or unscheduled maintenance procedures (engine installed).

Note 1:

These 1st line procedures are listed in the following pages in two groups:

Note 2: The accessories either have a TBO or are oncondition.

- Check and servicing procedures

Note 3: It is mandatory to refer to refer to the approved and current TURBOMECA maintenance technical publications to carry out any maintenance procedure.

- LRU removal and installation procedures.


LRU - Line Replaceable Unit.



ARRIUS 1

Training Notes

IDENTIFICATION Fire detectors Alternator - LP pump Oil-Fuel filter unit HP pump - Metering valve Stop electro-valve Valve assembly Start electro-valve Flow divider Start injectors Main injectors Drain valve Fuel preblockage switch Fuel pressure transmitter Ignition unit Igniter plug Ignition cableN1 sensor N2 sensor Torquemeter transmitter Conformation box Thermocouples Electrical harness Digital Control Unit P3 sensor T1 probe Exhaust pipe Heat protection Oil pump Strainers - Electrical magnetic plugs Min. oil pressure switch Oil pressure transmitter

REMARKS

ATTACHMENT 3 screws on the support 3 screws on the casing 4 screws 4 screws on the casing 2 screws on the flange 3 screws 2 screws on the support 2 screws 2 screws 2 screws Screwed onto the turbine casing 3 screws on the filter support secured by a clamp 3 screws on the support 2 screws on the casing Screwed to the unit 2 screws on the gearbox casing 6 screws on the gearbox casing Screwed on the gearbox casing 3 screws on the support 2 screws on the casing Clamps - screws Installed on the airframe Half-clamps and 2 screws 2 screws on the plenum Clamp 4 parts secured by locking wire 4 screws on the casing Screwed and bayonet Screwed on the gearbox casing Screwed on the gearbox casing

Polarity + or -

Do not remove the sleeves

Warning Warning Warning Possible adjustment Possible adjustment Colour code Colour code Removal-installation when the unit is turned-off From the higher diameter, observe the tightening torque Observe the tightening torque Coupling sleeve


1ST LINE MAINTENANCE PROCEDURES (O LEVEL) For training purposes only © Copyright - TURBOMECA



ARRIUS 1

Training Notes

1ST LINE MAINTENANCE PROCEDURES (O LEVEL) PRESERVATION AND STORAGE

Engine installed in the aircraft

General

- Housing the engine in a waterproof container with dessicant bags.

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 devices and close the cowlings • When the engine is not used between 7 days and 6 months, drain and replace the oil, do a 5 minute ground run every 7 days • When the engine is not used for more than 6 months, remove the engine and do the "long term" storage procedure.

If there is no container, the engine can be housed in a water and vapour proof cover with dessicant bags.

Storage inspection

When an engine is not used for a long time, it must be protected against corrosive agents. The most efficient preservation consists of: - Washing and protecting the air path by spraying a specific product

Once the engine has been put into storage, it must be periodically checked to ensure that it is in good condition. In the event of an anomaly, the preservation and storage procedures must be renewed.

Type of storage "Short term" storage Procedure which protects the engine for a duration of less than three months if the engine is not installed in the helicopter.

The max. duration of storage and inspection to be carried out vary with the type of container used.

"Long term" storage

Note: Refer to maintenance manual for preservation and storage procedures and periodicity.

Procedure which protects the engine for a duration of more than three months if the engine is not installed in the helicopter. The engine is then inhibited in the package (in a wooden case or in metal container).




ARRIUS 1

Training Notes

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

GENERAL - Protection against corrosive agents - Cleaning, internal and external protection

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 - ...

Refer to maintenance manual for preservation and storage procedures and periodicity

PRESERVATION AND STORAGE

1ST LINE MAINTENANCE PROCEDURES (O LEVEL) For training purposes only © Copyright - TURBOMECA



ARRIUS 1

Training Notes

2ND LINE MAINTENANCE PROCEDURES (I LEVEL) Modular design The engine is of modular construction. This concept avoids the return of the complete engine to a specialized workshop and thus provides a higher operational availability and a reduction of maintenance costs.

Modular replacement Each module is a unit which can be replaced without balancing or adaptation work. However, some precautions must be taken when replacing a module. This page mentions the main points related to this question: - Reasons for module removal • Inspection (access to some components) • Replacement

- 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 installation The procedure is carried out with a special tool with the engine in the vertical position and placed on module M02.

- Module identification • Identification plate on module • Compatibility table • Engine log book

Power turbine module removal and installation (only 1M version)

- Removal and installation conditions • Engine installed (or not) on the aircraft • Installation on working stand • Particular position (horizontal or vertical)

Note 1: In a training course, these procedures are dealt with in video and practical sessions.

- Tools • Standard tools • Special tools For training purposes only © Copyright - TURBOMECA

The procedure is carried out with a special tool with the engine in the vertical position and placed on module M02.

Note 2: It is mandatory to refer to refer to the approved and current TURBOMECA maintenance technical publications to carry out any maintenance procedure.



ARRIUS 1

Training Notes


MODULE M01 AND M02 REMOVAL AND INSTALLATION

POWER TURBINE MODULE REMOVAL AND INSTALLATION (1M version)

2ND LINE MAINTENANCE PROCEDURES (I LEVEL) For training purposes only © Copyright - TURBOMECA



Training Notes

ARRIUS 1

3RD LINE MAINTENANCE PROCEDURES (H LEVEL) Definition The 3rd line (or deep) maintenance procedures are carried out on removed major parts (e.g. modules) in a workshop. They consist of replacement or reconditioning of subassemblies without repair or adjustment (e.g. injection wheel replacement).

Procedure 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).




ARRIUS 1

Training Notes

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

3RD LINE MAINTENANCE PROCEDURES (H LEVEL) For training purposes only © Copyright - TURBOMECA



ARRIUS 1

Training Notes

4TH LINE MAINTENANCE PROCEDURES (D LEVEL) REPAIR AND OVERHAUL

Main steps of 4th line maintenance - Engine reception

Overhaul

- Disassembly

Overhaul is a major maintenance operation that must be carried out in a specific workshop when the engine (or module) has reached the end of its TBO or cyclic life. The overhauled engine (or module) is then put back into service with zero hours for a new TBO.

- Cleaning - Inspection - Investigation - Repair - Installation (of engine and accessories)

Repair

- Tests

Repair is a maintenance operation that must be carried out in a specific workshop when the engine (or module) is unserviceable or damaged.

- Delivery.

After a repair, the engine (or module) is returned to service with a TBO according to the work carried out and the engine standard. Note: TBO: Time Between Overhaul.




ARRIUS 1

Training Notes

4TH LINE MAINTENANCE WORKSHOP ENGINE OR MODULE DELIVERY AFTER OVERHAUL WITH FULL TBO, OR REPAIRED

ENGINE OR MODULE AT THE END OF TBO OR FOR REPAIR

ENGINE ASSEMBLY

TESTS

DISASSEMBLY - REPAIR ACCESSORY ASSEMBLY

DELIVERY DISASSEMBLY

INVESTIGATION ENGINE RECEPTION

REPAIR CLEANING

INSPECTION

REPAIR AND OVERHAUL

4TH LINE MAINTENANCE PROCEDURES (D LEVEL) For training purposes only © Copyright - TURBOMECA



ARRIUS 1

Training Notes

15 - TROUBLE SHOOTING - General ................................................................... 15.2 - Trouble shooting ................................................... 15.4 to 15.23



TROUBLE SHOOTING

ARRIUS 1

Training Notes

GENERAL Introduction

Repair procedure

Trouble shooting is a very important aspect of the maintenance.

The repair procedure should be guided by two main considerations:

Efficient diagnosis reduces the extra maintenance costs due to unjustified removals and additional diagnosis time.

- A minimum downtime - A justified removal of components.

In fact, even with a very high reliability product, failure is inevitable and required actions should be taken efficiently. After the fault analysis which consists of finding the effect of a given failure, this section considers the case in reverse; i.e.: finding the probable cause of a fault.

The procedure to be applied depends on the case but, in general, a good knowledge of the product and a methodic research would permit a safe diagnosis and a quick corrective action. In a general way, the procedure includes the failure identification, its analysis, the isolation of the defective component, and the repair choice.



TROUBLE SHOOTING

ARRIUS 1

Training Notes

Inevitable

Random

Fault (single, double, dormant)

Symptoms (and other additional indications…) All factors should be taken into consideration as well as the interactions.

Trouble shooting - Diagnosis - Remedy - Repair - Check

MTTR (Mean Time To Repair)

- Adequate means and procedures - Training of personnel

Analysis of the fault Identification of the faulty component Or other perception

Additional checks

Total time required for repairing

Deduction

Substitution

Remedy (adjustment, replacement, cleaning, repair...)

GENERAL For training purposes only © Copyright - TURBOMECA


TROUBLE SHOOTING

ARRIUS 1

Training Notes

On selection of start, N increases, but no increase in t4.5

The ignition system operates (noise of HE components)

No effect after selecting start N doesn't increase Yes

No

- Start electro-valve - Injectors

- HE ignition units - Igniters Note: Refer to the test procedure in order to discriminate

Possible start on 1 injector (or 1 igniter)

Is ventilation possible? No

Yes

- Circuit breaker, selector switch, relay - Digital Control Unit

Or fuel supply anomaly

Note: It is also possible to check the fuel flow through the combustion chamber drain.

- Starter contactor - Supply - Starter Note Yes

Note: Further tests (failure code, engaging noise of the contactor) help locate the failure.

Fuel flow

Ignition system

No

- Start electro-valve - Fuel supply

TROUBLE SHOOTING - STARTING FAULTS (1) For training purposes only © Copyright - TURBOMECA


TROUBLE SHOOTING

ARRIUS 1

Training Notes

Abnormal t4.5

t4.5 ≈ 200°C

Increase due to the injectors, but the main system is not supplied

t4.5 > 200°C but not sufficient

Anomaly during starting acceleration

t4.5 too high

- Digital Control Unit, - Digital Control Unit sensors, metering - Sensors valve. - Drain valve of the - Fuel supply combustion chamber (LP circuit, filters...)

Too quick or too slow N1 increase

The starter is not cut-out at self-sustaining speed

Abnormal idle speed

- Abnormal t4.5 - Starter system - Fuel system

- Digital Control Unit - Starter contactor

- Digital Control Unit - Fuel system

Anomaly during acceleration from idle to nominal N - Pressurising valve - Digital Control Unit

Note: In any case, check the electrical supply (battery voltage). Acceleration with surge

Acceleration (too slow or no acceleration)

No control


Digital Control Unit or hydromechanical part

Control: - Electronic part - Hydromechanical part

Other possibility: N and t4.5 increase, but no start

Failure of the accessory drive shaft

TROUBLE SHOOTING - STARTING FAULTS (2) For training purposes only © Copyright - TURBOMECA


TROUBLE SHOOTING

ARRIUS 1

Training Notes

Deceleration selected by moving the flight selector switch to the idle position

N1 deceleration

Yes

Yes

No

N1 stabilisation

Select stop position

No

- Selector - Digital Control Unit

Fuel system

The engine stops N1 , t4.5

No

Yes

Yes

Correct rundown time

Normal shut-down

No

- Selector - Stop electro-valve

The engine shut-down can then be affected by the manual fuel valve of the LP system. Further checking required.

Abnormal rubbing of the rotating assembly Note: A crank with the power turbine fixed (rotor break allows) discrimination between the gas generator and the power turbine.

TROUBLE SHOOTING - FAULTS DURING SHUT-DOWN For training purposes only © Copyright - TURBOMECA


TROUBLE SHOOTING

ARRIUS 1

Training Notes Dry crank selection (press and hold)

Note: 20 sec. max. limit to avoid starter overheat

N1 Indication

Yes

No

Gas generator rotates

The starter turns

Yes

No

Yes

Normal dry crank

Accessory drive train

N1 indication

No

Is starting possible? Yes

No

Dry crank control

- Starter - Starter contactor - 24V supply

TROUBLE SHOOTING - FAULT DURING DRY CRANK For training purposes only © Copyright - TURBOMECA


TROUBLE SHOOTING

ARRIUS 1

Training Notes

Abnormal oil pressure indication

Low

No pressure

- Oil condition - Seal - Blockage inside the system

Variation

High pressure

- Filter blockage indication - Pump valve

- Measuring system - Blockage of a jet

Low pressure indicator 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

TROUBLE SHOOTING - LUBRICATION FAULTS (1) For training purposes only © Copyright - TURBOMECA


TROUBLE SHOOTING

ARRIUS 1

Training Notes

Abnormal temperature indication

Low

High

Measuring system

- Measuring system - Insufficient cooling - Lubrication local anomaly, blockage of a jet

Abnormal oil consumption

Yes

No

Visible leak

External leak

Pipe or accessory seal on casing

Oil contamination

Internal leak

Contamination of the aircraft air tapping - Leak from the cold section of the labyrinth seal - Rear bearing housing or pressurisation of the labyrinth seal.

Detection

Corrective action

Magnetic plug Analysis Color, aspect

According to the amount, origin and rate of contamination…

Smoke and oil evidence in the exhaust pipe - Leak from the hot section - Rear bearing housing, or defective pressurisation of the labyrinth seal.

TROUBLE SHOOTING - LUBRICATION FAULTS (2) For training purposes only © Copyright - TURBOMECA


TROUBLE SHOOTING

ARRIUS 1

Training Notes

Unexpected shut-down

N2, N1, C, t4.5, and oil pressure decrease

Operation of the power turbine overspeed safety Yes

No

Water or ice ingestion

Actual overspeed Doubt

Yes

- Failure of the power transmission shaft - Control unit

No

Engine internal anomaly

Fuel supply: - Pump shaft failure - Pipe rupture - Water in fuel - Digital control unit

Safety system: - Loss of signal - Electronic box Note: Unlikely

Rearming and corrective actions

Note:

In a twin engine configuration, the engine which remains in operation supplies the required power up to a certain limit.

TROUBLE SHOOTING - FAILURE LEADING TO ENGINE SHUT-DOWN IN FLIGHT For training purposes only © Copyright - TURBOMECA


TROUBLE SHOOTING

ARRIUS 1

Training Notes

Abnormal gas temperature indication

Abnormally low

Fluctuation

Measuring system

Dirty compressor

Abnormally high Engine internal problem

Compressor surge

During start

In operation


Engine problem (air intake, compressor...) Loss of power

Max. N1 reached Yes

No

- Torque and gas temperature indication - Engine: compressor fouling, turbine creep, ...

- Blockage of the injection system - Fuel supply (pumps, filters...) - Digital Control Unit - Mode selector switch - T1 temperature probe

Note:

Particular attention: check of the max. N1.

TROUBLE SHOOTING - MISCELLANEOUS CASES (1) For training purposes only © Copyright - TURBOMECA


TROUBLE SHOOTING

ARRIUS 1

Training Notes

Gas generator speed - N1

Incorrect response time

Overspeed


- P3 supply to the Digital Control Unit - Gas generator

Unexpected acceleration

Unexpected deceleration

- 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")

Variations

- Air in the fuel system - Dirt in the fuel system - Constant P valve - Blockage of several main injectors - Digital Control Unit

Note: The total stabilisation of one engine, while the second engine is in normal operation, indicates a major failure ("fixed" metering valve).



TROUBLE SHOOTING

ARRIUS 1

Training Notes

Power turbine speed - N2

Incorrect speed

Overspeed

- N2 sensors - Indicators - Setting of the anticipator - Digital Control Unit - Abnormal operation of the gas generator

- Failure of the transmission shaft - Control system

Vibration

Power transmission shaft

Engine - aircraft alignment

Engine attachment

Rotating assembly of the gas generator or the power turbine



TROUBLE SHOOTING

ARRIUS 1

Training Notes Note: Failures which result in abnormal indication. - Inaccurate indication (transmitter / receiver) - Systems associated with the engine

Instruments

Refer to other cases Indicator lights Fire "failure"

Fire warning

Chip detection

Min. lubrication oil pressure Min. fuel pressure

Oil filter pre-blockage Fuel filter pre-blockage

Unexpected illumination

Open circuit

No illumination in test mode

Test system

Justified illumination

Overheat or fire


Bi-metallic strip broken

No illumination in test mode

Test system

No illumination in the event of overheat

Reverse terminals + or -


Particles on plug


Sensor "sensibility"

No illumination despite the deposits

Detectors


Pressure drop


Pressure switch

No illumination despite the pressure drop

Pressure switch


Blockage


Pressure switch

No illumination despite the differencial pressure increase

Pressure switch



TROUBLE SHOOTING

ARRIUS 1

Training Notes Note: Failures which result in abnormal indication

Overspeed rearming

Overspeed operation

Air bleed prohibiting (if installed)

Fixed metering valve (or major failure)


N2 sensors

No illumination

Overspeed system not rearmed


Overspeed

Unexpected illumination (at power on)

Overspeed system not rearmed


Exceeded OEI 30 min. rating


DCU, interfaces

No illumination

DCU, interfaces

Justified illumination: use the manual control

DCU, sensors ...

Illumination not justified: use the manual control

DCU

No illumination in case of a major failure: use the manual control

DCU


Sensor, Digital Control Unit or serial data link (refer to the alphadigital code)

Illumination not justified

DCU


N1, N2 sensors; DCU supply (refer to the alphadigital code)

Illumination not justified

DCU

Minor failure

Loss of redundancy



TROUBLE SHOOTING

Training Notes

ARRIUS 1

TROUBLE SHOOTING - FAULT FINDING Introduction We should note that a failure identification is easier when an integrated system is used (Digital Control Unit and alphanumeric display; refer to chapter "CONTROL AND INDICATION"). But a good knowledge of the engine and systems and a methodic research still remain necessary.

Procedure An anomaly detected by the Digital Control Unit, is indicated by the amber or red GOV warning light. To identify the failure, it is necessary to use the alphanumeric display. It is possible to choose the Memory mode for the faults occured during the last flight; Failure or Parameter modes for the faults in real time. The problems are displayed with three codes: A xxxx, B xxxx, C xxxx to which correspond three tables provided by the flight manual and maintenance manual. Another table provided by the maintenance manual supplies the procedure to follow (see next page).



TROUBLE SHOOTING

ARRIUS 1

Training Notes

ENGINE 1 ALPHANUMERIC DISPLAY ENGINE 2

ENGINE 2 DCU ENGINE 1 DCU ENGINE 2 SENSORS ENGINE 1 SENSORS

Parameter Ng

TEST

0 No failure

0 No failure

0 No failure

0 No failure

1 Input mod.

1 Power mod.

1 PITCH lane

1 Res.

2 Internal F.

2 Output mod.

2 T4.5 lane

2 Res.

Input mod. + 3 internal F.

Power mod. + 3 output mod.

PITCH lane + 3 T4.5 lane

3 Res. + Res.

4 External F.

4 Airspeed mod.

4 T1 lane

4 Selectors lane

5

Input mod. + external F.

5

Power mod. + speed mod.

5

PITCH lane + T1 lane

5

Selectors lane + Res.

6

internal F. + external F.

6

output mod. + speed mod.

6

T4.5 lane + T1 lane

6

Selectors lane + Res.

Input mod. + 7 Internal F. + external F.

Power mod. + 7 output mod. + speed mod.

PITCH lane + 7 T4.5 lane + T1 lane

Selectors lane 7 + Res. + Res.

8 Nil

8

8 P3 lane

8 TRIM lane

9

9

9 P3 lane + PITCH lane

9 TRIM lane + Res.

A

A

A TRIM lane + Res.

B

B

A P3 lane + T4.5 lane P3 lane + B PITCH lane + T4.5 lane

C

C

C P3 lane + T1 lane

C

D

D

P3 lane + D PITCH lane + T1 lane

E

E

E

TRIM lane + D Selectors lane + Res. TRIM lane + E Selectors lane + Res.

F

P3 lane + PITCH lane + F T4.5 lane + T1 lane

Ng TRIM NR ADJ

Failure Memory

SCROLL

INTEGRATED SYSTEM F

P3 lane + T4.5 lane + T1 lane

B TRIM lane + Res. + Res. TRIM lane + Selectors lane

TRIM lane + F Selectors lane + Res. + Res.

TROUBLE SHOOTING - FAULT FINDING For training purposes only © Copyright - TURBOMECA


TROUBLE SHOOTING

Training Notes

ARRIUS 1

TROUBLE SHOOTING - FAULT FINDING (CONTINUED) Procedure (continued) Example: A 4040 code or external failure (T1 probe channel). A failure external to the DCU requires a check of the corresponding harness and accessory (by means of an appropriate test box). The DCU can be incriminated because the failure can come from an external failure to the digital processing channel (e.g.: interconnection unit).



TROUBLE SHOOTING

ARRIUS 1

Training Notes 15 D TABLE DCU 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), LIGHTS

INDICATIONS

FAILURES

ACTIONS

OBSERVATIONS

Split within tolerances indicated by the fault display unit; resulting from a P0 difference between the 2 "Digital Control Units"

Compare P0 and QFE and change the Control Unit with the greatest P0 difference

The removed Digital Control Unit can be kept to check with another one having a similar P0 difference

Inner fault on the outlet module

Standard exchange of the Control Unit concerned by A-3000

Light "on" without fault display

Standard exchange of the Control Unit

Without fault indication, there is no more dialog with the Control Unit

Standard exchange of the Control Unit or fault display unit

Lights "on" without fault indication


X-xxxx

Fault code without light GOV; AMBER or RED

Standard exchange of the fault display unit

A-4000 B-0001 B-0002

Particular case

Standard exchange of the pump-metering valve unit and if the fault occurs again replace the Digital Control Unit

A-1xxx

Internal(s)


Minor fault light "on"

A-2xxx

Internal(s)



A-3xxx

Internal(s)



A-4040

External(s)

Check the harness and the sensor concerned taking into account the tenth digit which can help in finding the channel anomaly (e.g. : A-4040 = T1 probe channel)

Test box ref. 8815800000

A-5xxx A-6xxx A-7xxx

Internal(s) or External(s) Internal(s) or External(s) Internal(s) or External(s)

Apply the procedure for external faults A-4xxx then if no result, replace the Digital Control Unit


B-00x0

Internal(s)


B-000x

According to A-xxx code; internal or external

DIPO

AMBER GOV

A-3000

RED GOV EBUS

AMBER & RED GOV

RED GOV

FUEL and or

Example of codes for instruction purposes only. In all cases, refer to the maintenance manual.


TROUBLE SHOOTING - FAULT FINDING (CONTINUED) For training purposes only © Copyright - TURBOMECA


TROUBLE SHOOTING

Training Notes

ARRIUS 1

TROUBLE SHOOTING - DOCUMENTATION Chapter 71.00.09 of the Maintenance Manual, which is dedicated 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.



TROUBLE SHOOTING

ARRIUS 1

Training Notes

ARRIUS 1 MAINTENANCE MANUAL

Operating faults

CHAP. 71.00.09 TROUBLE SHOOTING

Maintenance faults

Fault codes

Trouble shooting tasks

TROUBLE SHOOTING - DOCUMENTATION For training purposes only © Copyright - TURBOMECA


TROUBLE SHOOTING

Training Notes

ARRIUS 1

TROUBLE SHOOTING - CONCLUSION Despite the high reliability of the product, failures remain inevitable and happen at random. But their rate and effects can be reduced if the "enemies" of the engine are taken into consideration. When the failure occurs, you have to be in a position to correct it.

"Enemies" of the engine The traditional adverse conditions for this type of engine are: - 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).



TROUBLE SHOOTING

ARRIUS 1

Training Notes

FUEL

ELECTRICITY

- Not in conformity with specifications - Water in fuel - Sulphur + salt in the air = sulfidation

- Too low voltage during starting - Interference

AIR

OPERATION

- Sand - Salt - Pollution

- "Non respect" of instructions and procedures - Severe operating conditions

OIL

MAINTENANCE

- Not in conformity with specifications - Contamination

- "Non respect" of inspection frequencies - Various mistakes - Wrong logistic

"ENEMIES" OF THE ENGINE

TROUBLE SHOOTING - CONCLUSION For training purposes only © Copyright - TURBOMECA


TROUBLE SHOOTING

ARRIUS 1

Training Notes

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



CHECKING OF KNOWLEDGE

ARRIUS 1

Training Notes

INTRODUCTION Method

Types of questionnaires

Continuous checking helps to ensure the information is assimilated. It is more a method of work than a testing in the traditional sense.

Several types of questionnaire can be employed during a course: - Traditional written questionnaire

Objectives of the questionnaires

- "Short answer" questionnaire

The questionnaires permit a progressive assimilation and a long term retention. The questionnaires are a subject for discussion (effects of group dynamics). They also permit students to consider important subjects several times under different aspects.

- Multi Choice Questionnaire (MCQ) - Oral questionnaire - Learning Through Teaching (LTT; the student has to explain a given subject).

Integration into the training programme - First hour every day for revision of the subjects previously studied - After each chapter (or module) of the course - At the end of the training course.


Examination The final examination at the end of the course consists of three tests: written, oral and practical. A certificate and an approval card are given to the student if the results are satisfactory.



ARRIUS 1

Training Notes

QUESTIONNAIRE 1 This traditional questionnaire is established according to the same plan as the Training Notes in which the answers can be found.

4 - Explain the principle of engine adaptation to helicopter power requirements.

Turboshaft engine

6 - How do temperature and altitude affect the engine performance.

1 - 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, in standard atmosphere): • Power on the shaft

5 - Give a definition of the operating ratings.

Engine 1 - List the main components of the gas generator. 2 - Describe the power turbine assembly. 3 - Describe the fuel injection system.

• Specific fuel consumption

4 - List the engine driven accessories.

• Compression ratio

5 - List the bearings which support the gas generator.

• Gas generator turbine entry temperature

6 - Describe the system used for the bearing sealing.

• Gas generator 100% rotation speed

7 - Describe the reduction gear assembly.

• Nominal power turbine rotation speed

8 - Describe the engine air intake.

• Output shaft rotation speed

9 - Describe how the modules are connected together.

• Mass of the engine with specific equipment.


10 - List the manufacturing materials of the engine main components.



ARRIUS 1

Training Notes

QUESTIONNAIRE 1 (continued) Oil system

7 - Give the operating procedure for manual fuel flow control.

1 - What type of system is it? 2 - At what pressure does the pressure warning light come on? 3 - Describe the oil filter assembly.

8 - Explain the operation of the system during starting.

Control system 1 - List the main functions of the control system.

4 - State the location of strainers and magnetic plugs. 5 - What is the max. oil consumption?

2 - Explain the basic principle of the control system. 3 - Explain the operating principle of the speed control.

Air system

4 - List the logic input signals of the DCU.

1 - List the functions ensured by the internal air system (secondary system).

5 - List the analog input signals of the DCU.

2 - List the function of the various air bleeds.

6 - Describe and explain the operation of the overspeed safety systems of the power turbine.

3 - Why are the starting injectors ventilated?

7 - Describe the Digital Control Unit.

4 - Explain the effect of air bleeds on engine performance.

Measurement and indicating systems

Fuel system

1 - List the indicating systems of the power plant.

1 - Type of main fuel injection?

2 - Describe the rotation speed indicating system of the power turbine.

2 - Describe the low pressure fuel pump assembly. 3 - Function of the relief valve of the high pressure pump.

3 - Explain the principle of the torquemeter system. 4 - Describe the t4.5 gas temperature indicating system.

4 - Describe the fuel filter assembly. 5 - Explain the principle of fuel injection (main and starting injection). 6 - What is the purpose of the constant ∆P valve. For training purposes only © Copyright - TURBOMECA



ARRIUS 1

Training Notes

QUESTIONNAIRE 1 (continued) Starting

Maintenance

1 - Describe the cranking function of the engine.

1 - List the main operating limitations of the engine (explain the reason for each limit).

2 - Describe the ignition system (ignition unit and igniter plugs). 3 - List the main phases of the starting cycle.

2 - Describe the engine starting procedure. 3 - List the main practices of a preventive periodic inspection.

4 - Describe the starting control electrical system.

4 - List the means used for "on condition monitoring".

Electrical system

5 - Describe the procedure for engine removal.

1 - List the electrical control components. 2 - Indicate the alternator location.

6 - List the technical publications used for engine maintenance.

3 - Describe the electrical harness and connectors.

7 - Do the "fault analysis" exercises. 8 - Do the "fault finding" exercises.

Engine installation 1 - Describe the attachment of the engine to the aircraft. 2 - Describe the engine power drive and the power transmission. 3 - List the various engine / aircraft connections. 4 - Describe the fire protection system of the engine.




ARRIUS 1

Training Notes

QUESTIONNAIRE 2

Questions

Answers

The following questions require short and accurate answers. The student can answer orally or in the space provided for the answers.

9 - Limit temperatures of the flight envelope? 10 - Max. starting altitude?

Questions

Answers

11 - Engine mass?

1 - Location of the Digital Control Unit?

12 - Max. gas temperature at the gas generator turbine entry?

2 - Direction of rotation of the power turbine?

13 - Air pressure at the compressor outlet?

3 - Engine air flow?

14 - Air temperature at the compressor outlet?

4 - Power turbine nominal rotation speed?

15 - Gas generator 100% rotation speed?

5 - Direction of rotation of the gas generator? 6 - Power on the shaft at take off rating?

16 - Type of compressor? 17 - Type of mounting of the power turbine blades?

7 - MTOP rating max. use duration?

18 - Number of bearings which support the power turbine shaft?

8 - OEI 2 min. 30 sec. rating max. use duration?

19 - Number of bearings which support the output shaft?




ARRIUS 1

Training Notes

QUESTIONNAIRE 2 (continued) Questions

Answers

Questions

Answers

20 - Location of the centrifugal breather?

30 - Setting of the oil filter by-pass valve?

21 - Number of power turbine bearings?

31 - Type of oil pressure transmitter?

22 - Type of seal on the power shaft?

32 - Location of the low oil pressure switch?

23 - Manufacturing material for the compressor?

33 - Oil pressure illuminating the indicator light?

24 - Number of stages of the gas generator turbine?

34 - How many oil pumps?

25 - Number of accessory drives?

35 - Location of the oil temperature probe?

26 - Number of bearings which support the gas generator?

36 - Filtering ability of the oil filter?

27 - Overall compression ratio?

37 - Type of oil pumps?

28 - Type of combustion chamber?

38 - Setting of the oil filter pre-blockage switch?

29 - Is the oil pressure adjustable?

39 - Max. oil consumption?




ARRIUS 1

Training Notes

QUESTIONNAIRE 2 (continued) Questions 40 - Air bleed for the power turbine bearing pressurisation?

Answers

Questions

Answers

50 - Start injector flow? 51 - Number of main injectors?

41 - Air bleed characteristics? 42 - Number of start injectors?

52 - Position of the fuel pump pressure relief valve in normal operation?

43 - Position of the combustion chamber drain valve engine stopped?

53 - Location of the alternator?

44 - Setting of the combustion chamber drain valve? 45 - Fuel specific consumption (at cruise rating)? 46 - Type of main fuel injection? 47 - Position of the stop electro-valve at engine shut-down? 48 - Position of the main metering valve in case of an electronic failure? 49 - Type of LP fuel pump?


54 - Number of gas generator rotation speed sensors? 55 - Number of thermocouple probes? 56 - Number of power turbine rotation speed sensors? 57 - Location of the torquemeter? 58 - Torquemeter average pressure at 100%? 59 - Type of connection thermocouples.

of

the



ARRIUS 1

Training Notes

QUESTIONNAIRE 2 (continued) Questions

Questions

Answers

Answers

60 - Overspeed safety setting of the power turbine?

69 - Procedure to be carried out if the engine is not expected to operate for more than 7 days?

61 - Type of ignition?

70 - Rundown check during engine shut-down: - Time?

62 - Max. duration of a ventilation?

- Noises? 63 - Gas generator speed at starter cutoff? 64 - Max. and min. temperatures of the starting envelope? 65 - Min. electrical voltage at starting? 66 - Number of engine electrical harnesses? 67 - Number of fire sensors? 68 - Is borescope inspection of the combustion chamber possible?


71 - Tolerance to apply to periodic inspections? 72 - Method to record the engine hours? from …… to …… 73 - Is the removal-installation of the power shaft seal possible in current maintenance? 74 - Document stating the basic and individual TBO's? 75 - Definition of a complete engine cycle? 76 - Definition of a partial cycle?



ARRIUS 1

Training Notes

QUESTIONNAIRE 2 (continued) Questions 77 - Stabilisation time before engine shut-down? 78 - Is a vibration check to be carried out with only one engine in operation ?

Questions

Answers

Answers

84 - Is it necessary to remove the centering sleeve when replacing a start injector? 85 - Procedure for cleaning the air tapping union restrictors?

79 - Procedure to be applied in the case of chip indicator "on" followed by a drop of engine power? 80 - What are the parameters affecting the oil pressure? 81 - Setting of the combustion chamber drain valve (expressed in N1)? 82 - How is the N1 speed sensor gap adjusted? 83 - Is the fuel filter pre-blockage pressure switch an LRU?




ARRIUS 1

Training Notes

QUESTIONNAIRE 3 This multi-choice questionnaire is used to review, in a relatively short time, certain important points and to test the acquired knowledge. Answers to the questions are to be found at the end of the questionnaire. 1 - The ARRIUS 1 engine is: a) a free turbine turboshaft engine b) a turbo-jet engine c) a fixed turbine turboshaft engine. 2 - Section of passage of the compressor diffusers: a) regular b) divergent c) convergent. 3 - Type of combustion chamber: a) annular with centrifugal injection b) annular, reverse flow c) annular, indirect flow. 4 - The power turbine shaft belongs: a) to the reduction gearbox b) to the power turbine c) to the gas generator. 5 - Type of exhaust pipe attachment: a) bolts b) mounting pads c) clamp.


6 - Number of bearings which hold the gas generator: a) 4 b) 2 c) 3 7 - The output shaft belongs to: a) gas generator b) power turbine c) reduction gearbox. 8 - Type of oil system: a) dry sump b) constant pressure c) lubrication by splashing. 9 - Setting of the oil filter pre-blockage switch: a) lower than the by-pass valve b) higher than the by-pass valve c) the same as the pump valve. 10 - The oil strainers are located: a) at the outlet of the pumps b) on the suction side of the scavenge pumps c) at the inlet of the lubricated components. 11 - Is there a max. oil temperature: a) yes, 60°C b) no c) yes, 110°C max.



ARRIUS 1

Training Notes

QUESTIONNAIRE 3 (continued) 12 - The air bled from the outlet of the centrifugal compressor wheel is used for the pressurisation of: a) some labyrinth seals b) the tank c) the pumps. 13 - The balance piston is balanced by: a) air bled from the middle of the centrifugal compressor b) air bled from the outlet of the compressor wheel c) air bled from the outlet of the centrifugal compressor diffuser. 14 - Type of ambient air temperature probe? a) platinum probe b) nickel probe c) thermocouple. 15 - Ventilation of starting injectors: a) does not exist b) is made with air from the compressor c) is made with atmospheric pressure air. 16 - The manual metering valve: a) does not control the metering unit b) controls the metering unit mechanically c) controls the metering unit electrically.


17 - The maximum rotation speed of the gas generator: a) is set by the control system b) is set by a mechanical stop c) there is no maximum speed. 18 - The signature box is part of: a) the torque indicating system b) the temperature indicating system c) does not exist. 19 - With the anticipator, the static droop is: a) compensated b) cancelled c) overcompensated. 20 - Type of Digital Control Unit: a) hydraulic b) analog c) digital electronic. 21 - The thermocouples are installed: a) in series b) in parallel c) on the turbine casing. 22 - The conformation box is used for: a) the synchronisation b) the torquemeter operation c) the gas temperature measurement.



ARRIUS 1

Training Notes

QUESTIONNAIRE 3 (continued)

5-c 10 - b 15 - b 20 - c 25 - a 30 - abc?

27 - Starting is possible with one igniter: a) yes b) no c) yes, in emergency. 28 - HE ignition means: a) Hot Electrode b) High Energy c) High Emission.

Answers


4-b 9-a 14 - a 19 - a 24 - b 29 - b

26 - The starter cut-out is made: a) automatically b) manually c) with air pressure.

3-b 8-a 13 - c 18 - c 23 - a 28 - b

25 - Number of N1 signals? a) 3 b) 4 c) 6

30 - The reliability of the engine is: a) good b) fairly good c) extremely good.

2-b 7-c 12 - a 17 - a 22 - c 27 - a

24 - Number of N2 signals? a) 2 b) 6 c) 3

29 - Borescopic inspection is used to check: a) the external parts condition b) the internal parts condition which are not accessible without removal c) the reduction gearbox condition.

1-a 6-b 11 - c 16 - a 21 - b 26 - a

23 - Number of thermocouples? a) 2 x 4 b) 2 x 5 c) 2 x 3



ARRIUS 1

Training Notes

QUESTIONNAIRE 4 This questionnaire is a sort of drill which is also used to test and perfect the knowledge acquired. 1 - List the reference stations (numbers) on the illustration below:

2 - Complete this table (with values): Ratings

shp

kW

N1

N2

2 min. 30 sec. 5 min. 30 min.

3 - Engine description - List the components on the diagram:

1


2

3

4

1 - ................................

3 - ................................

2 - ................................

4 - ................................



ARRIUS 1

Training Notes

QUESTIONNAIRE 4 (continued) 4 - Oil system - Name the components on the diagram:

3

1

7

8

4

2

6 5

1 - ..........................

2-

..........................

3-

.........................

4- ..........................

5 - ..........................

6-

..........................

7-

.........................

8- ..........................




ARRIUS 1

Training Notes

QUESTIONNAIRE 4 (continued) 5 - Air system - Indicate (with different colours) the following air circuits:

6 - Fuel system - Name the components:

a) pressurisation of turbine bearing seals b) pressurisation of the segments c) pressurisation of the balance piston d) cooling of turbine NGV.

5 4 6 1

3

2

1 - ................................................................................. 2 - ................................................................................. 3 - ................................................................................. 4 - ................................................................................. 5 - ................................................................................. 6 - .................................................................................




Training Notes

ARRIUS 1

QUESTIONNAIRE 4 (continued) 7 - Fuel system - Name the components of the metering unit assembly:

1 2

3

1 - ................................................................................ 2 - ................................................................................ 3 - ................................................................................




END of these training notes and (maybe also) of the course but n o t th e E N D o f y o u r tra in in g w hic h mu s t b e co n tin u e d (a g ain a n d a g ai n) ha rmon izin g k n o w led g e an d ex p e rie nc e . T H A N K Y O U fo r y o u r k in d atte nt ion . Au revoir Good bye Adiós Auf Wiedersehen Adeus Arrivederci Farvel To t z i e n s Adjö Näkemiin Antio Ma salaam Selamat Jalan

REMARKS Remarks (appreciations, criticisms, suggestions...) should be forwarded to: TURBOMECA CENTRE D'INSTRUCTION 40220 TARNOS - FRANCE

REMARKS CONCERNING THE TRAINING AIDS

REMARKS CONCERNING THE TRAINING COURSE

Name ....................................................................................................................................... . Address .................................................................................................................................... . Course .............................................................. from ............................to ............................. .

TURBOMECA Training Centre

Manual Entrenamiento Arrius Ia

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