English For Aircraft system maintenance 2 pot

Regulations, explanations, - present perfect ~ conditional - more complex conjunctions and longer sentences * Note: Only the Aircraft and Component Maintenance Manuals are written consis

ENGHIEY

ENGLISH FOR AIRCRAFT

En application de la loi du 11 mars 1957, il est interdit de repraduire intégralement ou partiellement le présent ouvrage sans autorisation de 'éditeur ou du Centre Frangais d'exploitation du droit de Copie (3, rue Haute feuille - 75006 Paris)

CONTENTS Foreword

ATA 21 Air Conditioning

ATA 22 Auto Flight

ATA 23 Communications

ATA 24 Electrical Power

ATA 25 Equipment and Furnishing

ATA 26 Fire Protection

ATA 27 Flight Controls

ATA 28 Fuel

ATA 29 Hydraulic Power

ATA 30 Ice and Rain Protection

ATA 38 Water and Waste

ATA 49 Airborne Auxiliary Power

FOREWORLS

FOR THE STUDENT

The aim

English for Aircraft will help you use

aeronautical manuals more easily It is designed

for civilian or military technicians engineers

and mechanics and can be used with a qualified

teacher in a training course or for self-study It is

for users of English with an intermediate level in

written English

The first volume Documentation Handbook,

contains the basic principles structure and

vocabulary of aeronautical English, with a large

number of authentic one-sentence examples

from all aircraft systems

System Maintenance is a companion volume to

the first It contains extensive texts and figures

which are practical examples of the principles

explained in the Documentation Handbook A

cross-reference system (p 332) enables you to

move from one volume to the other and

consolidate your knowledge

How is the book organized?

System Maintenance is divided into twenty-four

chapters, each one corresponding to a major

ATA system (or group of systems in the case of

the first and last chapters)

Every chapter begins with a checklist of basic

terms and ends with a short glossary that

provides a brief explanation of words of special

interest or difficulty The main body of the

chapter consists of a series of texts of various

types accompanied by numerous illustrations

and activities The activities are technically-

based as well as linguistic, enabling you to

explore both the technical content and the

language used, and to acquire essential reading

techniques

4

FOR TRAINING PURPOSES ONLY

You can check your answers to the exercises in the Exercise Key at the end of the book The Index gives you access to the terms explained in the glossaries at the end of each chapter

References in the margin to the Documentation

Handbook make it easy to find explanations of

the language, syntax and grammar used

A wide range of texts

In System Maintenance, we have used

documents which reflect the range of styles and difficulty that a fitter, a mechanic, a technician

or an engineer has to deal with today The texts are identified in such a way that it is very easy to select only the type of texts you actually need to

use,

The texts have been chosen to cover as wide a range as possible in the field of aircraft maintenance documentation You can choose the texts you want to study according to several variables :

- the ATA chapter;

- the type of document : AMM, SB, AD, TFU,

CMM, SRM, OIT, SIL, Technical Incident Reports, Technical Logs telexes and letters;

- conventional (A300, A310) or glass cockpit

(A320) technology:

- conventional English (A300, A310) or

Simplified English (A320)

Variety of language

The language varies in style and complexity The

table on the next page gives you a rough idea of the language you can expect to find in the various types of document

- function - present participle, gerund

- location - past participle, passive

> conjunctions

AD, TFU, Accounts of past events, 4-5 As above plus:

AOT OIT, SIL, on-going, incomplete and - past simple

reports, telexes, future actions - present continuous

letters Regulations, explanations, - present perfect

~ conditional

- more complex conjunctions and longer sentences

* Note: Only the Aircraft and Component Maintenance Manuals are written consistently in Simplified English and

this only since 1986,

Simplified English

Today, a relatively mature form of Simplified

English is used in the Aircraft Maintenance

Manuals and most Component Maintenance

Manuals of aircraft such as the A320, Fokker

100 B747-400, B737-500, B767, A340, A330

and other aircraft of this generation

This means that the ground engineer on the shop

floor working on these aircraft will be using job

cards and reading system descriptions in

Simplified English However, this is not always

the case when working on planes produced prior

to 1986 Therefore, even people working on the

basic documentation will be faced with both Sim-

plified and conventional English for some time

This is all the more true for Engineering

Departments where virtually none of the “day-

to-day” documentation issued -by the vendors

and manufacturers is in Simplified English Consequently, English for Aircraft is not a Simplified English manual: we have taken both forms of the language into account A short account of Simplified English is given on pages 195-202 of the Documentation Handbook

The activities There are three basic categories of activity, identified by one, two or three stars:

* rapid “scanning” or “skimming” activities to improve the speed, accuracy and efficiency of your reading

** linguistic activities to practise the syntax, grammar or vocabulary used in the documents

**%*% comprehension activities to check your understanding and your ability to use the technical content of the documents

FOR TRAINING PURPOSES ONLY

Points to remember

It is important, at least initially to approach the

texts only through the activities Do not try to

translate word for word or understand everything

in the texts

Most of the modules of texts and exercises

should only require about 20 minutes’ work

This means that it is easy to work regularly and

frequently

FOR THE TEACHER

The learning process

System Maintenance has been designed to

provide a reservoir of texts of convenient length

enabling the student or the teacher to go back

and forth between explanations and examples in

the first volume and application in the second

This pendular movement consolidates the

learning process

The variety of systems types of document and

types of activity make it easy to choose course

material according to the language ability,

technical background and professional ability of

the students

Every teacher will naturally draw on his or her

personal experience and skill to adapt these

materials to the needs and abilities of each

group Most of the exercises can be used

successfully in the form of pair work group

research, competitive team activities,

information exchange, etc

The aim of all the activities is to lead the student

gradually to acquire the various facets of an

effective reading technique In no case do the

activities represent an exhaustive treatment of a

text; it is always possible to go further

Returning to a text that has already been covered

is highly profitable

FOR TRAINING PURPOSES ONLY

Reading techniques The activities reflect the different skills or

knowledge necessary to read and use a technical document They include:

- vocabulary acquisition and expansion;

— recognition of verb forms, word endings, prefixes compound words, etc

~ recognition of the significance of the above as

regards their differences in functional and not just grammatical terms:

— a knowledge of basic English sentence

- the ability to find information quickly:

knowing where to look and what to look for:

— the ability to find the key words and the main

verb in a sentence:

- immediate recognition of the type of

information contained in a document or a sentence (e.g instruction description operation, location, purpose means cause conse-

quences ):

- the use of prior technical knowledge to

interpret a text:

— the ability to follow a logical thought process

in English and to visualize meaning, thereby reducing translation to a minimum;

— the creation of a “checklist” of points which should develop into an automatic reflex for tackling any document

Acknowledgements

I should especially like to thank Airbus Industrie for their kind permission to reproduce the texts and figures which make up a large part of the

book

My thanks also to Air France and Air Inter for the interest and encouragement shown by their

staff

Finally, I am very grateful to Jonathan Main for

all his assistance with the first draft of the

manuscript

Philip Shawcross

00 = Introduction SI Standard Practices and Structures

05 Time Limits/Maintenance 523 Doors

06 Dimensions and Areas 51+ _ Nacelles/Pylons

07 Lifting and Shoring 55 _ Stabilizers

08 Leveling and Weighing $6 Windows

09 Towing and Taxiing 357 Wings

10 Parking Mooring, Storage and

Return to Service

II Placards and Markings

I2 Servicing

AIRFRAME SYSTEMS POWER PLANT

20 Standard Practices-Airrame 70 Standard Practices-Engine 2L Air Conditioning 71 Power Plant

23 Communications 73 Eng Fuel and Control

24 Electrical Power 74 Ignition

25 _ Equipment/Furnishings 75 Air

26 — Fire Protection 77 Engine Indicating

27 ~~ Flight Controls 78 Exhaust

29 Hydraulic Power 80 Starting

30 Ice and Rain Protection

Here are some common aircraft parts, assemblies and sub-assemblies Use the list of ATA chapters to identify their chapter number as in the examples Check your answers in the Exercise Key

24 SURGE VENT TANK

38 CABIN SEATS

39 ALTITUDE KNOB

40 TRIM AIR VALVE

CENTER OF GRAVITY _ CABIN INTERCOMMUNICATION DATA SYSTEM CALIBRATION MEMORY MODULE

CABIN PRESSURE CONTROLLER CABIN PRESSURE CONTROLLER UNIT CENTRAL PROCESSOR UNIT

CATHODE RAY TUBE COMMAND SENSOR UNIT (SLATS/FLAPS) CARGO SMOKE DETECTION UNIT DIGITAL AIDS RECORDER

DIRECT CURRENT DECODER/ENCODER UNIT DEDICATED DISPLAY AND CONTROL UNIT DIGITAL FLIGHT DATA RECORDER

DIGITAL FLIGHT DATA RECORDING SYSTEM DISPLAY MANAGEMENT COMPUTER

DISTANCE MEASURING EQUIPMENT DATA MANAGEMENT UNIT

FULL AUTHORITY DIGITAL ENGINE CONTROL FLIGHT AUGMENTATION COMPUTER

FLIGHT CONTROL DATA CONCENTRATOR FLIGHT CONTROL UNIT

FUEL CONTROL UNIT FUEL LEVEL SENSING AMPLIFIER FUEL LEVEL SENSING CONTROL UNIT FLIGHT MANAGEMENT AND GUIDANCE SYSTEM FLIGHT MANAGEMENT AND GUIDANCE COMPUTER FIRST OFFICER

FEEDBACK POSITION PICK-OFF UNIT FUEL QUANTITY INDICATION COMPUTER FUEL QUANTITY INDICATOR

FLOW REGULATION UNIT PASSENGER ADDRESS PITCH ATTITUDE SENSOR PASSENGER ASSIGNMENT SYSTEM PUSH BUTTON

PASSENGER CALL BUTTON PRINTED CIRCUIT BOARD

9

FOR TRAINING PURPOSES ONLY

PCU PCU PES PFD PHC P&T PIU PTU

POWER CONTROL UNIT PASSENGER CONTROL UNIT PAX ENTERTAINMENT SYSTEM PRIMARY FLIGHT DISPLAY PROBES HEAT COMPUTER PROGRAMMING AND TEST PASSENGER INFORMATION UNIT POWER TRANSFER UNIT

* Put these words in the correct order and find the acronym (abbreviation),

1, DIGITAL AUTHORITY FULL CONTROL ENGINE

2, PRESSURE CABIN CONTROLLER

3 SYSTEM ENTERTAINMENT PAX

3 Reconstitute the complete words from the following contractions

Before you read this chapter, check that you know these important terms

Mark a tick ( W) if you do If you do not, use the glossary, a dictionary or ask a colleague

JACKING OF THE MAIN LANDING GEAR

+ ———— DOUBLE FLAP MLG TIRES

WEIGHT AND SALANCE | SENSOAS

=HE-

B A When the aircraft is on its wheels, remove the hydraulic jack

B Remove the wheel chocks

c C Install the wheel chocks:

- on the wheels of the nose landing gear

~ on the wheels of the main landing gear that it is not necessary to

change

D Make sure that the jack adaptor is in the correct condition

To prevent this, operate the hydraulic control of the jack slowly

4 Procedure

aftward in position so that its adaptor is under the ball-pad of the shock absorber

Put the jack in position so that the adaptor touches the bail-pad

Make sure that this assembly is level

Make sure that the aircraft is clear to lift

Make sure that the parking brake is released

15 FOR TRAINING PURPOSES ONLY

OILS PREFORMED PACKING

TOOLS AND OTHER ITEMS

4 Procedure

A

B

C

Remove the oil-fill plug (1)

Remove and discard the preformed packing (2)

Slowly add OILS (Material No 03-003) to the flap PCU gearbox until it comes out of the oil-fill hole

Clean the oil-fill plug (1) with a clean lint-free cloth

Lubricate a new preformed packing (2) with OILS

Install the new preformed packing (2) on the oil-fill plug (1)

- Install the oil-fill plug (1) and TORQUE it to between 2.0 and 2.5 m daN (14.74 and 18.43 Ib ft)

Remove unwanted oil from near the oil-fill plug (1) with a clean cloth Examine the preformed packing (2) for signs of oil leakage

5 Close-up

A Remove the container

Remove the warning notice(s)

Cc Make sure that the work area is clean and clear of tool(s) and other items,

Close the right MLG door

Remove the safety clip(s) and the tag(s) and close this (these) circuit breaker(s): 6CV, 8CV

Remove all the ground support equipment, the maintenance equipment, the standard and special tool(s) and all other items

Flap Power Control Unit

FOR TRAINING PURPOSES ONLY

ACCESSORY GEARBOX DRAIN PLUG

FLUSHING OF OIL SYSTEM

50 DRAIN PLUG

FOR TRAINING PURPOSES ONLY

A Completely oil from tank

B Completely drain oi! from accessory section

oil system with new oil

system

E Completely drain oil from tank

F Completely drain oil from accessory drive section

scavenge filters

If deposits are normal (non-metallic chips) clean and install If

uw (Ref TSM 710000001)

1 Operate engine at ground for 10 minutes

K.Check for undesirable products in oil by sight and by

E through K

WARNING: DO NOT REMOVE THE FILLER CAP OF THE OIL

TANK IMMEDIATELY AFTER ENGINE OPERATION

THE OIL PRESSURE DECREASE FOR A MINIMUM OF 5 MINUTES AFTER THE ENGINE SHUTDOWN

IF YOU OPEN THE FILLER CAP WHEN THERE IS IN THE TANK THE OIL CAN BURN YOU DANGEROUSLY

supply the common scavenge filters

WARNING: DO N OT ‘REMOVE THE FILLER CAP OF THE OIL

OPERATION LET THE OIL PRESSURE

FOR A MINIMUM OF 5 MINUTES

THERE is PRESSURE IN THE TANK THE OIL

N Fill oil tank to maximum

4 Close-up

A Make sure that the work area is clean and trang of

(s) and other items

19

FOR TRAINING PURPOSES ONLY

OIL SERVICING (2)

4 * Identify and classify the verbs used in this procedure The first paragraph (job set-up) is already here as an example

3 Job Set-up

A Make sure that you put a warning notice in the cockpit to tell persons not

to operate the Landing gear

B Make sure that you show a warning notice to tell persons not to operate

the Landing gear doors

C Put an access platform in position below the applicable shock absorber

4 Procedure

A Aircraft on the Ground

(1) Examine the gland seals of the shock absorber for signs of oil leaks

(2) Measure and write down the shock absorber extension (dimension ‘H’)

20

FOR TRAINING PURPOSES ONLY

2

DOCUMENTATION

HANDBOOK 8,G

(4) Install the standard charging equipment on the charging valve

(5) Slowly open the charging valve (1)

(6) Read and write down the pressure shown on the pressure gage

(7) Close the charging valve (1)

(8) Use the graph and the pressure you wrote down, to find the correct value of dimension ‘H’ for the ambient temperature Compare this value with the dimension ‘H’ you wrote down

(9) If the dimension ‘H’ is not correct:

(a) Connect a nitrogen source to the standard charging equipment (b) Adjust the nitrogen source to give the necessary pressure

WARNING: MAKE SURE THAT THE AREA AROUND THE

AIRCRAFT IS CLEAR OF PERSONS AND EQUIPMENT WHEN YOU PRESSURIZE/

DEPRESSURIZE THE SHOCK ABSORBER,WITH THE AIRCRAFT WEIGHT ON THE GROUND, THE AIRCRAFT WILL MOVE

(c ) Slowly open the charging valve (1)

(d) Monitor the dimension ‘N’ and adjust the pressure until the dimension ‘N’ is correct

(e) When the dimension ‘N’ is correct, close the charging valve (1) (f) Stop the supply from the nitrogen source Release the pressure

and remove the nitrogen source from the standard charging

equipment

(10) Remove the standard charging equipment from the charging valve (1) (il) TORQUE the charging valve (1) to between 0.57 and 0.79 m.daN (50.44 and 69.91 Ibf in) and install the blanking cap (2)

(12) Examine the charging valve (1) for leaks

%* There are 7 location words used in this procedure What are they?

MAJOR AIRCRAFT DIMENSIONS

terms for these dimensions

() Basic horizontal area

(2) Basic vertical area

WARNINGS AND CAUTIONS

The Maintenance Manual is full of WARNINGs and CAUTIONS On the next

few pages are examples from many different aircraft systems The activities

that follow help you with the language and expressions

Rauchmaske

BEFORE SUPPLYING EXTERNAL AIR,ENSURE THAT AT LEAST ONE WINDOW OR PASSENGER DOOR

tS OPEN AND REMAINS OPEN DURING SERVICING

TO REPLACE PANEL PULL PANEL DOWNWARD UNTIL RED LEVER ENGAGES

ACCES NON AUTORISE ENTRANCE PROHIBITED

No smoking

in lavatory

Pnère de verrouiller la porte Please lock door

DO NOT INTERRUPT, DURING OPERATION

There are risks to you and other persons when you work with composite

repair materials To prevent risks, read and obey the warnings given below WARNING:

CARBON DUST IS ELECTRICALLY CONDUCTIVE AND CAN CAUSE AN EXPLOSION WHEN YOU WORK WITH CFRP COMPOSITE MATERIALS IMMEDIATELY REMOVE DUST WITH A VACUUM CLEANER

USE AN ISOLATION TRANSFORMER WHEN YOU USE MAINS ELECTRIC POWER ON THE AIRCRAFT YOU MUST ONLY USE POWER TOOLS AND EQUIPMENT THAT ARE EXPLOSION PROOF

THE CORRECT FIRE FIGHTING EQUIPMENT MUST BE AVAILABLE NEAR THE WORK AREA BEFORE YOU START WORK IN A FUEL TANK

USE THE APPROVED HAND AND EYE PRO- TECTION WHEN YOU APPLY THE SEALANT ITIS A SKIN IRRITANT

DO NOT GET THE COMPOUND ON YOUR SKIN

IF YOU DO:

- RUB IT OFF IMMEDIATELY WITH A CLEAN CLOTH

- WASH THE SKIN WITH SOAP AND RINSE WITH CLEAN WATER

BEFORE PRESSURIZING HYDRAULIC SYSTEMS, CHECK THAT ALL CONTROLS ARE SET TO CORRESPOND WITH THE ACTUAL POSITION ON THE SERVICES THEY OPERATE

BEFORE PROCEEDING WITH MAINTENANCE WORK ON

OR NEAR MECHANICAL FLIGHT CONTROLS OR PRIMARY FLIGHT CONTROL SURFACES, LANDING GEARS, ASSOCIATED DOORS OR ANY MOVING COMPONENT, MAKE CERTAIN THAT GROUND SAFETIES AND/OR WARNING NOTICES ARE IN CORRECT POSITION TO PREVENT INADVERTENT OPERATION

OF CONTROLS

FOR TRAINING PURPOSES ONLY

OBEY THE MANUFACTURER’S INSTRUCTIONS

PUT ON PROTECTIVE CLOTHING,

DO NOT GET THEM IN YOUR MOUTH

DO NOT SMOKE

DO NOT BREATHE THE GAS

THESE MATERIALS ARE POISONOUS AND FLAMMABLE AND SKIN IRRITANTS

GET MEDICAL HELP IF YOUR SKIN OR EYES BECOME IRRITATED

LANDING GEAR - SERVICING MAKE SURE THAT THE GROUND SAFETY-LOCKS ARE

IN POSITION ON THE LANDING GEAR

DO NOT PUT COMPRESSED GAS IN CONTACT WITH YOUR SKIN THE GAS CAN GO THROUGH THE SKIN AND MAKE BUBBLES IN THE BLOOD THIS CONDITION CAN KILL YOU

LET THE BRAKES AND THE WHEELS BECOME COOL BEFORE YOU GO NEAR THE LANDING GEAR DO NOT APPLY A LIQUID OR GAS FIRE EXTINGUISHER DIRECTLY ON A HOT WHEEL OR BRAKE UNIT THIS COULD CAUSE AN EXPLOSION

CUT THE TUBE SLOWLY AND SMOOTHLY TO MAKE SURE THAT THE END OF THE TUBE DOES NOT CHANGE ITS SHAPE

FULLY CLEAN THE STEM WITH Material No 11-

003 IF IT TOUCHED HYDRAULIC FLUID

THEN DRY IT IMMEDIATELY

DO NOT EXTEND THE SLATS AND FLAPS WHEN THE THRUST REVERSER COWLS ARE DEPLOYED IN THE 45° POSITION

MAKE SURE THAT THE TRAVEL RANGES OF THE FLIGHT CONTROLS ARE CLEAR

IF YOU GET THE FLUID ON YOUR SKIN OR IN YOUR EYES:

- FLUSH IT AWAY WITH CLEAN WATER

- GET MEDICAL AID

instructions with a tick (’)

1 MAKE SURE Cj 5 DO NOT EXTEND LÌ

LJ

%* Make a scan of (read quickly) the texts and find the words which you can

classify under these categories

4 * Find the actions associated with each of these items

5 * x Place these words in the correct sentence

COULD CAN PREVENT AVOIDED MUST CAREFUL CANCELS REQUIRES ALLOWED DONOT MAKE SURE OBEY

1 This condition Kill you

2 This cause an explosion

3 No step on the whole surface

4 the travel ranges are clear

5 cleaning agent contamination by pouring

6 the manufacturer's instructions

7 You use only power tools

8 warning notices are in correct position to inadvertent operation of controls

10 The accomplishment of this service bulletin the previous requirements

11 If interference cannot be using these methods contact Airbus

12 Removal of the six inserts heating

All these sentences come from the warnings and cautions on the previous pages Read them again Repetition helps you remember better

FOR TRAINING PURPOSES ONLY

GLOSSARY0-20

Here is a glossary of some terms from the texts in ATA chapters 0-20 It is

not complete, but explains some important words You can add a translation

in your own language

to do, to perform particles they stop wheels at parking stand

# dirty

to remove obstacles free of obstacles distance between two objects

to conform to, to obey

to command

to press, to push indication

"

LOWER (1) MANDATORY PLACARD

REQUIRE (1) SECURE (:)

STEPS TAG TIP TOWING TRAVEL RANGE

WIDTH

WING SPAN

FOR TRAINING PURPOSES ONLY

to incorporate, to include

a part used to attach or instal

to clean to wash to rinse with fluid not permitted

risk danger damage to humans used to lift aircraft/gear

to move up without particles

to move down compulsory necessary sign notice

to stop to avoid

to need

to attach, to keep in position

to position stairs for access label

extremity, end pulling aircraft zone of movement distance from side to side distance between two wing tips

HOT

ICE INLET

NOZZLE OUTFLOW VALVE OUTLET

PACK

PRESSURE

RAM AIR RING

TRIM AIR

VENT (v.) WARM LILILILILILILILILILILILILILIL]

31

FOR TRAINING PURPOSES ONLY

32

MODIFIED DUCTS AND AIRFLOW

SERVICE BULLETIN (A)

On in-service aircraft, cracks, caused by vibration, have been discovered on

refrigeration unit intermediate ducts

To remedy this condition, improved intermediate ducts (addition of three additional riveted stiffeners) have been installed on aircraft MSNO37 thru 052

on production line

As this solution proved to be an unsatisfactory improvement, it is recommended to replace existing intermediate ducts by reinforced ducts (with all stiffeners completely riveted)

This new technical status has been incorporated on production aircraft

MSNO053 and subsequent

DESCRIPTION Accomplishment of this Service Bulletin consists in carrying out the following jobs on the aircraft: `

(1) Removal of refrigeration units (2) Removal of cooling air intermediate ducts (3) _ Installation of new cooling air intermediate ducts (4) Installation of refrigeration units

APPROVAL This Service Bulletin is approved by the Airworthiness Authorities

FOR TRAINING PURPOSES ONLY

To improve conditioning airflow regulation in flight compartment

When both packs are operating, some flight crews find that airflow is too

high

This Service Bulletin proposes addition of a manual control electric valve

on air supply duct to permit variation of airflow in flight compartment

according to flight crew \requirements

In order to alleviate the jinconvenience resulting from excessively long lead

time for availability of Service Bulletin 21033 kits, a particular scheme has

been implemented This)scheme calls for reduced air flow in the cockpit in

compliance with Mod 1620 requirements

This Service Bulletin covers this particular scheme

Accomplishment of this temporary solution consists in carrying out the following jobs on the air¢raft:

(1) Modification on air conditioning duct in zone 121 between

FR.14A/STA1187 and FR.18/STA 1340

(a) Removal and modification of the old duct

(b) Installation of duct mounting brackets

(c) Installation of the modified duct

1 *x** Read the two SBs and fill in this table

1 Which components are

** These words/expressions are used in both SBs Write them next to their

synonyms (words with the same meaning)

INCORPORATED ⁄/ TOO HIGH - IMPROVED

CARRYINGOUT ~ ITIS RECOMMENDED TO REQUIREMENTS

IN COMPLIANCE WITH ;

34

FOR TRAINING PURPOSES ONLY

_ AIR-COOLING SYSTEM

AMM A320 21.52.00

RAM AIA INLET

INLET ACTUATOR (REF 2t-81-00}

x In the text on the following page the ends of some words are missing Try

to find what is missing, (e.g ED, S, ING, ER, OR, ES, IES)

%* Do not read the text in detail Simply find and underline or highlight these prefixes and suffixes

DOCUMENTATION

HANDBOOK D EX- BY- RE- IN- HIGH- DIS- OUT- ANTI- DOWN- OVER- -TYPE

-FLOW -OFF -UP

35

FOR TRAINING PURPOSES ONLY

FOR TRAINING PURPOSES ONLY

4 Operation (Ref Fig 002)

A Normal Operating Mode When the bleed air enters the system, it is coolad_ in the primary heat exchang zx with ambient ram air Part of this air pass@_ through the

bypass valve 1OHH (30HH) (Ref 21-61-00) the remainder is then

compress «“ (in the air-cycle machine compress), which increases the temperature and pressure It is coola/_ again in the main heat exchanger with ambient ram air The air now enters the high-pressure water- extraction loop, where it is cooled to about its dew point This happen —_

in the reheater which uses turbine inlet air The condenser then uses cold turbine air to further cool the air to below its dew point Condensed water is then extracte¢_ and drain;z from the air, as it passes through

ambient ram airflow to help cool it The air re-enters the reheater where it is heated before being expandz¢ and cooled in the air-cycle machine turbine After pass.» through the condenser the now

condition£7 air leaves the air cool‘.: system

To prevent freezing at low ambient temperatures and to limit high pack discharge temperatures, the water extractor outlet temperature is

limits to between 2 DEG, C (35.60 DEG.F) and to 70 DEG C (158.00 DEG F) Air is bled from the compressor inlet through the

bypass valve 1OHH (30HH) to the turbine outlet This modulates pack discharge to the required level, if the limits for the water

extractor are not exceeded An anti-ice valve 17HH (37HH) (Ref 21-61-00)

is used to stop (as a back-up) ice formation downstream of the turbine When a significant pressure drop is sense the valve opens,

tapp¬„_ hot air from downstream of the flow control 8HB (11HB) This hot air is deliveré.4_ to the turbine which eliminates any ice formation

The ambient ram air for heat exchanger cooling enter%_ the air cooling system through fully modulated NACA-type inletg_ After pass_v through the primary heat exchanger and main heat exchanger the air is discharga/ overboard through a variable outlet When the aircraft is on the ground, the air-cycle machine fan supplizs the cooling airflow During flight the inlet and outlet areas are moduated so that the airflow

kept to a minimum During takeoff and landing, the inlet is fully close2

to prevent the ingestion of foreign matter

AIR CYCLE MACHINE

A320 AMM AIR CYCLE MACHINE 21.52.00 p 5

NOY AIR INLET

FOR TURBINE

ANTIAICING AND ACM HOT AIR

TEMP, CONTROL BYPASS

TURBINE INLET

SECTION BEARING AA

VENTILATION

COMPRESSOR TURBINE INLET \

COMPRESSOA OUTLET ScAOLL HOTAIA eee BYPASS

COMPRESSOR

INLET

FOR TRAINING PURPOSES ONLY

† *x** Answer these questions about the following text

1 There are 3 materials in this text What are they?

DOCUMENTATION

HANDBOOK H A B Œ

2 What is the purpose of/reason for

A air tapped from the turbine inlet?

B the labyrinth seals?

C the stainless steel nozzle, in case of turbine break up?

3 What is the most important component of the air-cycle machine?

4 Which of these words or expressions is not in paragraph B?

ALONG SELF- THRUST LOADS RAM LEAKAGE NOZZLE CENTER OUTER THROUGH INCASEOF HOUSING BEARING

B Air-Cycle Machine (Ref Fig 004)

The main component of the air-cycle machine is a rotating shaft A turbine, a compressor and a fan are mounted along the shaft The shaft rotates on two self-acting foil-air bearings, a double self-acting air- thrust bearing takes the axial thrust loads Air tapped from the turbine inlet,

is used to cool the bearing and then discharged into the ram airflow Labyrinth seals reduce air leakage between static and rotating parts The light-alloy turbine is supplied with air through a stainless-steel nozzle and a light-alloy scroll In case of turbine break up, the stainless-steel nozzle acts

as a containment ring The light-alloy centrifugal compressor is mounted in

the center of the rotating shaft Air is supplied from a light-alloy scroll An

outer scroll has a stainless-steel diffuser In case of a compressor break up, the stainless-steel diffuser acts as a containment ring Fan air is discharged through a conical nozzle, this gives a jet-pump effect in the fiberglass plenum diffuser The primary heat exchanger outlet is connected to the discharge ram airflow through the fiberglass diffuser

38

FOR TRAINING PURPOSES ONLY