32-LANDING GEAR

A319/A320/A321TECHNICAL TRAINING MANUAL

MECHANICS / ELECTRICS & AVIONICS COURSE

32 LANDING GEAR

This document must be used for training purpose only

Under no circumstances should this document be used as a reference.

It will not be updated.

All rights reserved.No part of this manual may be reproduced in any form,

by photostat, microfilm, retrieval system, or any other means,without the prior written permission of Airbus Industrie.

GENERAL** System Presentation (1) 1.......................** System Controls & Indicating Present. (1) 9....

LANDING GEAR AND DOORS** Retraction/Extension Presentation (1) 13.......** System Indications (1) 23.......................** System Warnings (3) 27..........................** System Normal Operation (3) 31..................** Free Fall Extension (3) 47......................** Safety Precautions (2) 57.......................** Doors Ground Operation (2) 65...................** Doors Ground Opening D/O (3) 71.................** LGCIU Control Signals (3) 77....................** LGCIU Monitoring Interfaces (3) 81.............** MLG Description (2) 87..........................** MLG Doors Description (2) 97....................** NLG Description (2) 101.........................** NLG Doors Description (2) 105...................** Landing Gear Components (2) 109.................** Landing Gear Components (3) 115.................

WHEELS AND BRAKES** Brake System Presentation (1) 137...............** Brake System Description (3) 151................** Auto-Brake System D/O (3) 155...................** Anti-Skid Function (3) 159......................** Brake Hydraulic System Operation (3) 163.......** Brake Temperature System Presentation (3) 173..** Brake Cooling System Presentation (1) 177......** ECAM Page Presentation (1) 181..................** System Warnings (3) 185.........................** Normal Braking Components (3) 187...............** Alternate Braking Components (3) 209...........** Parking Brake Components (3) 227................

** Wheel Components (3) 237........................** Brake Temperature System Components (3) 249....** Brake Cooling System Components (3) 253........

NOSE WHEEL STEERING** System Presentation (1) 257.....................** System Description/Operation (3) 261...........** ECAM Page Presentation (1) 267..................** System Warnings (3) 271.........................** Components (2) 273...............................** Components (3) 277...............................

BRAKING AND STEERING** BSCU Control Interfaces (3) 285.................** BSCU Architecture & Monitoring INTFC (3) 289...

TIRE PRESSURE INDICATING** System Presentation (1) 295.....................** System Description/Operation (3) 299...........** System Warnings (3) 303.........................** Components (3) 305...............................

MAINTENANCE PRACTICES** MLG Servicing (3) 313............................** MLG Shock Absorber Servicing (3) 319...........** Low PRESS Circuit Filling and Bleeding(3) 337..** Wheel and Brake R/I (2) 341.....................** CFDS Specific Page Presentation (3) 347........

_A319/A320/A321 TECHNICAL TRAINING MANUAL32 LANDING GEARMECHANICS / ELECTRICS & AVIONICS COURSE

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32 LANDING GEAR

UFD4200 TABLE OF CONTENTS Page

32 CONTENTSPage i

Dec 31/00


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EFFECTIVITYALL

32 LANDING GEAR

UFD4200 TABLE OF CONTENTS Page

32 CONTENTSPage ii

Dec 31/00

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32 - LANDING GEAR

32-00-00 GENERAL SYSTEM PRESENTATION

CONTENTS:GearExtension/RetractionBrakesSteeringSelf Examination

TMULDG101 LEVEL 1

EFFECTIVITY 32-00-00 Page 1Feb 29/96


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Page 1EFFECTIVITYALL

LANDING GEAR GENERAL SYSTEM PRESENTATION

GEAR

The landing gear consists of a forward retracting nosegear and two inboard retracting main gear legs.Each gear has an oleopneumatic shock absorber and isequipped with two wheels.Each main wheel is fitted with anti-skid wheel brakes.The two-wheel nose gear comprises an oleopneumaticshock absorber and a nose wheel steering system.

TMULDG101-T01 LEVEL 1



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LANDING GEAR GENERAL SYSTEM PRESENTATIONTMULDG101-P01 LEVEL 1



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EXTENSION/RETRACTION

Gear and doors are electrically controlled andhydraulically operated by the green hydraulic system.The hydraulically operated doors open during landinggear transit.These doors close each time the landing gear is fullyextended or retracted.The doors which are fitted to the landing gear strutsare mechanically operated by the gear and close at theend of gear retraction.

BRAKES

Carbon multidisc brakes are installed on the main gearwheels.During take-off, the nose wheels are automaticallycentered by means of two centering cams.




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STEERING

The nose wheel steering system is electricallycontrolled and is powered by the green hydraulicsystem.This enables an available powered steering over therange of 74° below 22 knots.In addition, the aircraft can be towed or pushed backto a nose wheel angle of 95° from the aircraftcenterline after inserting a steering pin without anymechanical disconnection.




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SELF EXAMINATION

Which hydraulic system powers normal landing gearoperation ?

A - Green system.B - Blue system.C - Yellow system.

Which hydraulic system powers the nose wheelsteering ?

A - Green system.B - Blue system.C - Yellow system.

TMULDG101 LEVEL 1



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32 - LANDING GEAR

32-00-00 GENERAL LANDING GEAR SYSTEMCONTROLS AND INDICATINGPRESENTATION

CONTENTS:Landing Gear PanelAuto Brake PanelA/SKID & N/W STRG SwitchTriple IndicatorLanding Gear Control LeverGravity Extension Crank HandleParking Brake HandleECAM System DisplayRudder PedalsNose Wheel Steering HandleBrake Fan Control Panel

TMULD40ZZ LEVEL 1

EFFECTIVITY 32-00-00 Page 1Oct 31/97


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GENERAL LANDING GEAR SYSTEM CONTROLS AND INDICATING PRESENTATION

LANDING GEAR PANEL

Two indications are provided for each gear :- a red "UNLK" light indicates that thecorresponding gear is not locked in theselected position,

- a green triangle indicates that the relatedgear is locked down.

AUTO BRAKE PANEL

The three auto brake pushbuttons (LO, MED, MAX) controlthe arming of the required deceleration rate.The "ON" light comes on blue when the relatedpushbutton is selected and the system is armed.The "DECEL" light comes on green when the correctdeceleration is reached.

A/SKID & N/W STRG SWITCH

The A/SKID & N/W STRG switch is normally in the "ON"position and it is used to isolate anti-skid and nosewheel steering functions.When it is set to "OFF", the DC supply of the Brakingand Steering Control Unit (BSCU) is isolated.

TRIPLE INDICATOR

The triple indicator displays the yellow brakeaccumulator pressure.It also displays the yellow braking pressure deliveredto the left and right hand brakes.

LANDING GEAR CONTROL LEVER

The landing gear lever must be pulled before selectingone of the two possible positions.When the landing gear is not downlocked in landingconfiguration, the red arrow of the control lever comeson.

GRAVITY EXTENSION CRANK HANDLE

When the normal extension system fails, the gear canbe extended by gravity.The crank handle must be pulled, then rotated threeturns clockwise.

PARKING BRAKE HANDLE

When the parking brake handle is pulled and turned tothe "ON" position, yellow pressure is applied to thebrakes.

CAUTION : No progressive pressure can be applied usingthe parking brake system.As long as the parking brake handle is "ON",brake pressure is not necessarily applieddue to limited autonomy of the systemaccumulator.

ECAM SYSTEM DISPLAY

The ECAM "WHEEL" page displays landing gear and doorpositions, as well as braking and steering indications.

TMULD40ZZ-T01 LEVEL 1



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GENERAL LANDING GEAR SYSTEM CONTROLS AND INDICATING PRESENTATIONTMULD40ZZ-P01 LEVEL 1



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GENERAL LANDING GEAR SYSTEM CONTROLS AND INDICATING PRESENTATION

RUDDER PEDALS

Manual Braking is provided by the Captain and FirstOfficer brake pedals.Nose wheel steering is also provided by the Captainand First Officer rudder pedals.

NOSE WHEEL STEERING HANDLE

The steering handwheels control the nose wheel steeringangle up to 74° in either direction.On each handwheel, a rudder pedal disconnect pushbuttonallows the rudder pedal steering orders to bedisconnected.

BRAKE FAN CONTROL PANEL (OPTIONAL)

The BRK FAN pushbutton is used to operate the brakefans when a brake overheat is detected.

TMULD40ZZ-T01 LEVEL 1



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32 - LANDING GEAR

32-30-00 LANDING GEAR RETRACTION/EXTENSIONPRESENTATION

CONTENTS:PrincipleNormal RetractionNormal ExtensionFree Fall ExtensionSelf Examination

TMULDGD05 LEVEL 1

EFFECTIVITY 32-30-00 Page 1Nov 30/98


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LANDING GEAR RETRACTION/EXTENSION PRESENTATION

PRINCIPLE

Gear and door sequencing is electrically controlledby Landing Gear Control and Interface Units (LGCIU) 1and 2.Each Landing Gear Control Interface Unit in turncontrols a complete gear cycle : one "UP" selectionand one "DOWN" selection.They switch over automatically at each retractioncycle, or in case of sequencing system failure.The gear up and down positions and the door close andopen positions are monitored by duplicated detectors.An interlock mechanism prevents unsafe retraction bylocking the lever in the "DOWN" position when any shockabsorber is not extended.NOTE : The nose wheel is automatically centered by a

cam when the shock absorber is extended.The two systems are electrically segregated withdifferent connections on the related selector valves.The landing gear is powered by the green hydraulicsystem. In case of failure, the gear can be extendedmechanically from the cockpit by means of a gravityextension crank handle.The safety valve cuts landing gear hydraulic supplyin normal landing gear retraction/extension ; thecut-out valve cuts landing gear hydraulic supply infree fall extension.LGCIU 1 provides gear positions to the landing gearindicator panel.LGCIU 1 and 2 provide gear and door positions to theECAM system.Other aircraft systems are linked to the LGCIUs for"flight/ground" signals.

TMULDGD05-T01 LEVEL 1



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LANDING GEAR RETRACTION/EXTENSION PRESENTATION (PRINCIPLE)TMULDGD05-P01 LEVEL 1



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NORMAL RETRACTION

At this stage of the operation, the landing gear isdown and locked.The aircraft is in flight configuration.Landing Gear Control and Interface Unit 1 is incommand.Landing Gear Control and Interface Unit 2 is instandby.At each gear UP selection, there is a changeover fromLGCIU 1 to LGCIU 2 (or vice versa).

Landing gear retraction cycle :- DOORS OPEN.- GEAR RETRACTS : When all hydraulic operated

doors are fully open, thelanding gear is controlled toretract.

- DOORS CLOSE : When all the landing gear islocked up, the doors arecontrolled to close.

The hydraulic supply to the landing gear circuit isautomatically cut off by a safety valve above 260knots.




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TMULDGD05-P02 LEVEL 1

LANDING GEAR RETRACTION/EXTENSION PRESENTATION (NORMAL RETRACTION)



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NORMAL EXTENSION

All gears are retracted and uplocked, all doors areclosed and uplocked and the safety valve is closed.At each gear DOWN selection, the safety valve opensand the LGCIU in command controls the extensionsequence.

Landing gear extension cycle :- DOORS OPEN.- GEAR EXTENDS : When all hydraulic operated

doors are fully open, thelanding gear is controlled toextend.

- DOORS CLOSE : When all the landing gear islocked down, the doors arecontrolled to close.




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TMULDGD05-P03 LEVEL 1

LANDING GEAR RETRACTION/EXTENSION PRESENTATION (NORMAL EXTENSION)



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FREE FALL EXTENSION

Rotation of the handle closes the cut out valve andconnects all landing gear hydraulic components to thereturn line, and releases door and gear uplocks.The doors stay open. The main landing gear is lockeddown by spring forces. The nose landing gear is lockeddown by aerodynamic forces.Then the landing gear lever must be set to down inorder to switch off the UNLK lights.

NOTE : As the landing gear system is depressurized andthe nose landing gear doors stay open, the nosewheel steering is lost.




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LANDING GEAR RETRACTION/EXTENSION PRESENTATION (FREE FALL EXTENSION)TMULDGD05-P04 LEVEL 1



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SELF EXAMINATION

What controls the landing gear normal operatingsequence ?

A - Either LGCIU in turn.B - Both LGCIUs simultaneously.C - The crank handle.

Which unit gives the landing gear position to ECAMdisplay ?

A - Either LGCIU in turn.B - Both LGCIUs simultaneously.C - LGCIU 1 only.

When does the automatic changeover of the LGCIUs incontrol occur?

A - When "DOWN" is selected.B - When "UP" is selected.C - When the first engine starts.

TMULDGD05 LEVEL 1



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32 - LANDING GEAR

32-61-00 LANDING GEAR SYSTEM INDICATIONS

CONTENTS:Landing Gear System Indicator PanelECAM PageSelf Examination

TMULDG501 LEVEL 1



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LANDING GEAR SYSTEM INDICATIONS

The landing gear indicator panel indicates the landinggear positions monitored by Landing Gear Control andInterface Unit 1 (LGCIU 1).This indicator has to be used as a back up. The primaryindication system, displayed on the ECAM, receivesdata from both LGCIUs.

LANDING GEAR SYSTEM INDICATOR PANEL

UNLOCK LIGHTAn "UNLK" light is provided for each gear.It comes on red when the corresponding gear is notlocked in the selected position.

TRIANGLE LIGHTA green triangle light comes on when the correspondinggear is locked down.

ECAM PAGE

L/G POSITION INDICATIONSThe different landing gear positions are monitored byboth Landing Gear Control and Interface Units and aredisplayed on the WHEEL page as shown on the tablebelow.

L/G UP LOCK INDICATIONSThe "UP LOCK" indication appears amber if therespective up lock is engaged when the gear is lockeddown."UP LOCK" (amber) : In our example the nose gear andthe right main gear up locks are engaged while thegear is locked down.

L/G DOOR POSITION INDICATIONSThe landing gear door position indications aredisplayed as shown on the table below.

L/G CTL INDICATIONA "L/G CTL" (Landing gear control) indication appearsamber in case of disagreement between the landing gearlever and landing gear position.




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LANDING GEAR SYSTEM INDICATIONSTMULDG501-P01 LEVEL 1



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SELF EXAMINATION

When does the UNLK light come on ?A - When the gear and the related doors are

not locked up.B - When the gear is not locked down.C - When the gear is not locked in the

selected position.

TMULDG501 LEVEL 1



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32 - LANDING GEAR

32-61-00 LANDING GEAR SYSTEM WARNINGS

CONTENTS:Gear Not DownlockedGear Not DownShock Absorber FaultDoors Not ClosedGear Not UplockedGear Uplock FaultLGCIU 1 (2) FaultSystem Disagree

TMULDA601 LEVEL 3

EFFECTIVITY 32-61-00 Page 1Sep 30/99


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TMULDA601-P01 LEVEL 3

LANDING GEAR SYSTEM WARNINGS



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TMULDA601-P02 LEVEL 3

LANDING GEAR SYSTEM WARNINGS



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TMULDA601 LEVEL 3



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32 - LANDING GEAR

32-31-00 LANDING GEAR NORMAL OPERATION

CONTENTS:ExtensionRetractionSelf Examination

TMULDGE03 LEVEL 3



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LANDING GEAR NORMAL OPERATION

EXTENSION

DOOR OPENINGWhen DOWN is selected, the Landing Gear Control andInterface Unit takes the control of the extensionsequence.The LGCIU signals the doors to open via selector valvesand the door proximity detectors signal the doors’fully open position back to the LGCIU in order tocontinue the sequence.

TMULDGE03-T01 LEVEL 3



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LANDING GEAR EXTENSION - DOOR OPENINGTMULDGE03-P01 LEVEL 3



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EXTENSION

GEAR DOWNWhen ALL doors are fully open, the LGCIU commands agear extension while maintaining the doors "open"signal.The gear proximity detectors signal to the LGCIU thatthe gears are downlocked.




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LANDING GEAR EXTENSION - GEAR DOWNTMULDGE03-P02 LEVEL 3



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EXTENSION

DOOR CLOSINGWhen ALL the gear is down and locked, the LGCIU signalsthe doors to close and lock stay actuators topressurize, while maintaining the gear extendedsignal.Door closing hydraulic pressure is fed to the lockstay actuators to back up the downlock springs.Door uplock proximity detectors signal to the LGCIUthat the doors are uplocked.As the doors begin to close, the LGCIU cancels thegear extended signal while maintaining the door "close"signal.




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LANDING GEAR EXTENSION - DOOR CLOSINGTMULDGE03-P03 LEVEL 3



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RETRACTION

Setting the landing gear control lever to UP causessystem 1 and 2 changeover. This allows the system whichwas previously in standby to control the nextretraction and extension sequence.Each Landing Gear Control Interface Unit controls onecomplete gear cycle: one UP selection and one DOWNselection.

DOOR OPENINGThe LGCIU must detect all three shock absorbersextended before allowing the selection of the landinggear control lever to UP.The LGCIU signals the doors to open via selectorvalves, and the doors proximity detectors signal thedoors’ fully open position back to the LGCIU, in orderto continue the sequence.




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LANDING GEAR RETRACTION - DOOR OPENINGTMULDGE03-P04 LEVEL 3



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RETRACTION

GEAR UPWhen ALL doors are fully open, the LGCIU signals thelanding gear to raise while maintaining the doors"open" signal to keep the doors "open" linepressurized.The gear uplock proximity detectors signal the LGCIUthat the gear is uplocked.




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LANDING GEAR RETRACTION - GEAR UPTMULDGE03-P05 LEVEL 3



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RETRACTION

DOOR CLOSINGWhen ALL the landing gear is up and locked, the LGCIUsignals the doors to close while maintaining landinggear UP signal to keep the "raise" line pressurized.Door uplock proximity detectors signal the LGCIU thatthe doors are uplocked.As soon as the last door closes and locks, the LGCIUcancels the landing gear "raise" signal and maintainsthe door close signal as long as the safety valve isopen.




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LANDING GEAR RETRACTION - DOOR CLOSINGTMULDGE03-P06 LEVEL 3



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RETRACTION

HYDRAULIC SHUT OFFAir Data Inertial Reference Units 1 and 3 send a signalto the safety valve to shut off the hydraulic pressureto the landing gear system.When the airspeed is greater than 260 ±5 kts thehydraulic circuit to the landing gear is depressurized.




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LANDING GEAR RETRACTION - HYDRAULIC SHUT OFFTMULDGE03-P07 LEVEL 3



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SELF EXAMINATION

What is the normal retraction sequence?A - Door open, gear up, door close, cancel

gear up signal.B - Door open, gear up, door close, maintain

gear up signal.C - Door open, gear up, door close, cancel

door close signal.

Before the landing gear can be retracted, what mustthe LGCIU detect?

A - Three shock absorbers extended.B - Three shock absorbers compressed.C - Only one shock absorber extended.

When is the hydraulic circuit depressurized afterretraction?

A - As soon as the selector lever is movedto neutral.

B - As soon as the airspeed is greater than260 ± 5 kts.

C - As soon as the last door is closed.

TMULDGE03 LEVEL 3



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32 - LANDING GEAR

32-33-00 LANDING GEAR AND DOORS - FREEFALL EXTENSION

CONTENTS:GeneralInitial ConfigurationLever Movement up to 1.5 TurnsLever Movement between 1.6 and 1.8 TurnsLever Movement between 1.9 and 3 TurnsSelf Examination

TMULDGL02 LEVEL 3

EFFECTIVITY 32-33-00 Page 1Jan 31/95


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LANDING GEAR AND DOORS - FREE FALL EXTENSION

GENERAL

Free fall extension is used either when :- both LGCIUs have failed,- green hydraulic low pressure,- one door cannot be opened hydraulically,- one gear leg cannot be lowered hydraulically.

If both LGCIUs fail the solenoids are not energizedand the door "close" lines are not pressurized.If the green hydraulic pressure is low the door "close"lines are not pressurized.

INITIAL CONFIGURATION

The safety valve is open and residual pressure suppliesthe door "close" line downstream of the selector valve.Gears and doors are uplocked.Note that the door bypass valves (1, 2 and 3) are onlyoperated during ground maintenance.

TMULDGL02-T01 LEVEL 3



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FREE FALL EXTENSION - INITIAL CONFIGURATIONTMULDGL02-P01 LEVEL 3



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LEVER MOVEMENT UP TO 1.5 TURNS

Rotating the gravity extension crank handle initiallyoperates the cut-out valve and both vent valves todepressurize the system by connecting the entirelanding gear hydraulic system to return.




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FREE FALL EXTENSION - LEVER MOVEMENT UP TO 1.5 TURNSTMULDGL02-P02 LEVEL 3



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LEVER MOVEMENT BETWEEN 1.6 AND 1.8 TURNS

Then the door uplocks are released.




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FREE FALL EXTENSION - LEVER MOVEMENT BETWEEN 1.6 AND 1.8 TURNSTMULDGL02-P03 LEVEL 3



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LEVER MOVEMENT BETWEEN 1.9 AND 3 TURNS

Finally the gear uplocks are released and the landinggear extends by gravity.

NOTE: Normal landing gear operation is restored byrotating the crank handle 3 turnsanti-clockwise.




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FREE FALL EXTENSION - LEVER MOVEMENT BETWEEN 1.9 AND 3 TURNSTMULDGL02-P04 LEVEL 3



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SELF EXAMINATION

What happens when the gravity extension crankhandle is rotated?

A - The cut-out and vent valves operate.B - The safety and cut-out valves operate.C - The safety and vent valves operate.

TMULDGL02 LEVEL 3



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32 - LANDING GEAR

32-00-00 LANDING GEAR SAFETY PRECAUTIONS

CONTENTS:Landing Gear Control LeverHydraulic

TMULDGJ02 LEVEL 2



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LANDING GEAR SAFETY PRECAUTIONS

LANDING GEAR CONTROL LEVER

The lever is locked in the "DOWN" position by aninterlock mechanism as soon as either Landing GearControl and Interface Unit (LGCIU) detects any shockabsorber not extended or nose wheels not centered.

NOTE : Nose gear shock absorber extended and nosewheels centered signal comes from the sameproximity detectors.

TMULDGJ02-T01 LEVEL 2



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LANDING GEAR SAFETY PRECAUTIONS - LANDING GEAR CONTROL LEVERTMULDGJ02-P01 LEVEL 2



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HYDRAULIC

Be sure that all safety precautions are carried outbefore working on landing gear :

- wheel chocks are in place,- hydraulic system is depressurized,- safety sleeves and safety pins are fitted onthe landing gear and landing gear doors,

- ground door opening handles are in the openposition.

MLG AND MLG DOOR SAFETY DEVICES(see following page).




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LANDING GEAR SAFETY PRECAUTIONS - MLG AND MLG DOOR SAFETY DEVICES

TMULDGJ02-P02 LEVEL 2



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HYDRAULIC

NLG AND NLG DOOR SAFETY DEVICES(see following page).




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LANDING GEAR SAFETY PRECAUTIONS - NLG AND NLG DOOR SAFETY DEVICESTMULDGJ02-P03 LEVEL 2



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TMULDGJ02 LEVEL 2



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32 - LANDING GEAR

32-00-00 LANDING GEAR DOORS GROUNDOPERATION

CONTENTS:Main Landing Gear Door Ground OperationNose Landing Gear Doors Ground Operation

TMULDGC03 LEVEL 2

EFFECTIVITY 32-00-00 Page 1Jul 31/96


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LANDING GEAR DOORS GROUND OPERATION

MAIN LANDING GEAR DOOR GROUND OPERATION

The main landing gear doors can be opened on the ground,for servicing or inspection purposes.

DOOR OPENING PREPARATIONPrecautions have to be taken before the doors areopened:Outside,

- ground safeties and main wheel chocks, inplace,

- downlock safety pin, IN.In the cockpit, put the warning notices on,

- the free fall handle and on the landing gearcontrol lever,

- make sure that the green hydraulic system isdepressurized.

Outside again,- make certain that the door travel ranges are clear.

DOOR OPENINGStand forward of the door. Open, the blue hydraulicbay servicing panel for the left hand side door or theyellow hydraulic bay servicing panel for the righthand side door.Disengage the safety pin, press the button at the endof the handle, rotate the handle to the open position.The door opens by gravity.Safety it when fully opened.

CAUTION: A SAFETY SLEEVE MUST BE FITTED ON THE ACTUATORPISTON ROD IMMEDIATELY AFTER IT HAS BEENOPENED ON THE GROUND, AND BEFORE WORKING INTHE GEAR WELL.

DOOR CLOSING PREPARATIONAfter servicing, the door can be closed.Here are the precautions that have to be taken:In the cockpit,

- landing gear control lever DOWN with thewarning notice in position,

- landing gear free fall crank handle in thenormal position: folded and a warning noticein position,

- green hydraulic system depressurized.On the ground,

- make certain that the ground door openingcontrol handle is locked in the OPEN position,

- remove the safety sleeve from the actuator,- make certain that the door travel ranges areclear.

In the cockpit again,- make sure that the external power is ON,- pressurize the green hydraulic system,- check the pressure on the ECAM page.

DOOR CLOSINGOn the ground,

- Reposition the ground door opening controlhandle in the CLOSED position (the door closes)and put the safety pin back in position,

- close the access panel.In the cockpit,

- check that doors are UP and LOCKED, on theWHEEL ECAM page,

- depressurize the hydraulic systems,- and remove the warning notices.

TMULDGC03-T01 LEVEL 2



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LANDING GEAR DOORS GROUND OPERATION - MAIN LANDING GEAR DOOR GROUND OPERATIONTMULDGC03-P01 LEVEL 2



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NOSE LANDING GEAR DOORS GROUND OPERATION

The nose landing gear doors can be opened on the ground,for servicing or inspection purposes.

DOORS OPENING PREPARATIONSome precautions have to be taken before the doors areopened:Outside,

- ground safeties and nose wheel chocks, inplace,

- downlock safety pin, IN.In the cockpit,

- put warning notices on the free fall handleand the landing gear control lever,

- make sure that the green hydraulic system isdepressurized.

Outside again,- make certain that the door travel ranges areclear.

DOORS OPENINGStand AFT of the gear leg.Disengage the safety pin, press the button at the endof the handle and rotate the handle to the openposition.Doors open by gravity.Lock them with the safety pins.

CAUTION: A SAFETY PIN MUST BE FITTED ON EACH DOORIMMEDIATELY AFTER IT HAS BEEN OPENED ON THEGROUND AND BEFORE WORKING IN THE NOSE GEARWELL.ADJUST THE DOOR POSITION MANUALLY TO EASE THEINSTALLATION OF THE SAFETY PIN IF NECESSARY.

DOORS CLOSING PREPARATIONAfter servicing, the doors can be closed, here aresome precautions that have to be taken:In the cockpit,

- landing gear control lever DOWN with thewarning notice in position,

- landing gear free fall crank handle in thenormal position: folded and the warning noticein position,

- green hydraulic system depressurized.On the ground,

- make certain that the ground door openingcontrol handle is locked in the open position,

- remove the safety pin from the doors,- make certain that the door travel ranges areclear.

In the cockpit again,- make sure that the external power is ON,- pressurize the green hydraulic system,- check the pressure on the ECAM page.

TMULDGC03-T02 LEVEL 2



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LANDING GEAR DOORS GROUND OPERATION - NOSE LANDING GEAR DOORS GROUND OPERATIONTMULDGC03-P02 LEVEL 2



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NOSE LANDING GEAR DOORS GROUND OPERATION (CONTINUED)

DOORS CLOSINGOn the ground,

- reposition the ground door opening controlhandle in the CLOSED position (the doors close)and put the safety pin back in position.

In the cockpit,- check that doors are UP and LOCKED, on theWHEEL ECAM page,

- depressurize the hydraulic systems,- and remove the warning notices.

TMULDGC03 LEVEL 2



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32 - LANDING GEAR

32-00-00 LANDING GEAR DOORS GROUNDOPENING DESCRIPTION/OPERATION

CONTENTS:GeneralMain DoorsNose DoorsHydraulic Operation

TMULDGW01 LEVEL 3

EFFECTIVITY 32-00-00 Page 1Aug 31/96


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LANDING GEAR DOORS GROUND OPENING DESCRIPTION/OPERATION

GENERAL

Each main door and nose door has a ground door openingsystem that comprises these primary components :

- a ground door opening control handle,- a mechanical transmission,- a by-pass valve,- a release mechanism in the door uplock.

The control handle has two lockable positions.When it is set to the "DOOR OPEN" position, it causesthe mechanical system to :

- operate the door by-pass valve,- release the door from its uplock.

This prevents a hydraulic lock, and allows thehydraulic fluid to be released from the door actuatingcylinder "DOOR CLOSED" line. The door then moves bygravity.

MAIN DOORS

The ground opening control handle is located forwardof the respective main landing gear bay into thehydraulic compartment. This location places theoperator in a safe position with a clear view of thedoor travel.The handle is connected through a push-pull cable tothe door by-pass valve on the outboard side of themain landing gear bay.

NOSE DOORS

The ground opening control handle is located in ahousing in the aft of the nose landing gear bay. Thislocation places the operator in a safe position witha clear view of the door travel.The handle is connected to a lay shaft on the doorby-pass valve and the door uplock on the left handside wall of the nose landing gear bay.

TMULDGW01-T01 LEVEL 3



UFD4200


LANDING GEAR AND DOORS GROUND OPENING DESCRIPTION/OPERATION - MAIN DOORS - NOSE DOORSTMULDGW01-P01 LEVEL 3



UFD4200


LANDING GEAR DOORS GROUND OPENING DESCRIPTION/OPERATION

HYDRAULIC OPERATION

Each by-pass valve has three hydraulic connectionsmarked A, B and C.

- port A : door open line,- port B : door close line from the selectorvalve,

- port C : door close line to the door actuatingcylinder.

During normal operation of the landing gear, port Ais closed and port B is connected to port C allowingthe respective door actuating cylinder and door uplockto be operated.When the ground door opening control handle isoperated, port B is closed and port A is connected toport C.A locking plunger in the by-pass valve stops themovement of the control lever from the "DOOR OPEN" tothe "DOOR CLOSED" position.Before any selection can be made, a hydraulic pressuregreater than 70 bars (1015 psi) must be supplied toport B to retract the locking plunger.

TMULDGW01-T02 LEVEL 3



UFD4200


LANDING GEAR AND DOORS GROUND OPENING DESCRIPTION/OPERATION - HYDRAULIC OPERATIONTMULDGW01-P02 LEVEL 3



UFD4200



TMULDGW01 LEVEL 3



UFD4200


32 - LANDING GEAR

32-31-00 LANDING GEAR AND DOORS - LGCIUCONTROL SIGNALS

CONTENTS:Up SelectionDown SelectionDoor UplocksDoor Fully OpenGear UplocksGear DownlocksExtended or CompressedDoor Selector ValveGear Selector ValveL/G Retraction Interlock SolenoidLGCIU 2

TMULDGG01 LEVEL 3

EFFECTIVITY 32-31-00 Page 1Dec 31/94


UFD4200


LANDING GEAR AND DOORS - LGCIU CONTROL SIGNALS

UP SELECTION

Two UP selection signals which come from the lever,are sent to the Landing Gear Control Interface Unit(LGCIU) to initiate the gear retraction sequence.

DOWN SELECTION

Two DOWN selection signals coming from the lever, aresent to the LGCIU to initiate the gear extensionsequence.

DOOR UPLOCKS

Three door uplock signals which come from door uplockproximity detectors, are sent to the LGCIU to indicatewhether doors are uplocked, or not.

DOOR FULLY OPEN

Four door fully open signals (two for nose doors) whichcome from the corresponding proximity detectors, aresent to the LGCIU to indicate whether doors are fullyopen, or not.

GEAR UPLOCKS

Three gear uplock signals which come from gear uplockproximity detectors, are sent to the LGCIU to indicatewhether gears are uplocked, or not.

GEAR DOWNLOCKS

Three gear downlock signals which come from geardownlock proximity detectors, are sent to the LGCIUto indicate whether gears are down and locked, or not.

EXTENDED OR COMPRESSED

Three shock-absorber signals which come from the oleoproximity detectors are sent to the LGCIU to indicatewhether shock-absorbers are compressed, or not.Note that nose landing gear "flight" information isgiven when the gear is extended and wheels are in thecentered position.

DOOR SELECTOR VALVE

After analysing all the input signals, the LGCIU sendstwo signals to the corresponding solenoid of the doorselector valve according to the position of the gears.

GEAR SELECTOR VALVE

After analysing all the input signals, the LGCIU sendstwo signals to the corresponding solenoid of the gearselector valve according to the position of the doors.

L/G RETRACTION INTERLOCK SOLENOID

After analysing all shock absorber signals, the LGCIUsends a signal to the lever interlock solenoid toprevent gear retraction if any shock absorber iscompressed.

TMULDGG01-T01 LEVEL 3



UFD4200


LGCIU CONTROL SIGNALSTMULDGG01-P01 LEVEL 3



UFD4200


LANDING GEAR AND DOORS - LGCIU CONTROL SIGNALS

LGCIU 2

Same control signals for LGCIU 2.Four signals are used by the LGCIU for systemselection:

- two for system 1 status,- two for system 2 status.

TMULDGG01-T01 LEVEL 3



UFD4200


32 - LANDING GEAR

32-60-00 LANDING GEAR AND DOORS - LGCIUMONITORING INTERFACES

CONTENTS:ARINC and Indicator PanelDiscrete

TMULDGH01 LEVEL 3



UFD4200


LANDING GEAR AND DOORS - LGCIU MONITORING INTERFACES

ARINC AND INDICATOR PANEL

After analyzing both gear uplock and downlock signals,the LGCIU sends up to six signals to the correspondinglights on the landing gear indicator panel.

TMULDGH01-T01 LEVEL 3



UFD4200


LGCIU MONITORING INTERFACES - ARINC AND INDICATOR PANELTMULDGH01-P01 LEVEL 3



UFD4200


TMULDGH01-P02 LEVEL 3

LGCIU MONITORING INTERFACES - DISCRETE - LANDING GEAR COMPRESSED



UFD4200


TMULDGH01-P03 LEVEL 3

LGCIU MONITORING INTERFACES - DISCRETELANDING GEAR EXTENDED - DOWNLOCKED - UPLOCK UNLOCKED



UFD4200



TMULDGH01 LEVEL 3



UFD4200


32 - LANDING GEAR

32-11-00 LANDING GEAR AND DOORS - MAINLANDING GEAR DESCRIPTION

CONTENTS:GeneralMain FittingSliding Tube/AxleActuating CylinderSide Stay AssemblyLock StayLock Stay ActuatorTorque Links/Slave LinkTorque Link Damper

TMULDAI09 LEVEL 2



UFD4200


LANDING GEAR AND DOORS - MAIN LANDING GEAR DESCRIPTION

GENERAL

Each Main Landing Gear (MLG) includes these parts:- a main fitting,- a sliding tube,- a shock absorber,- a retraction actuating cylinder,- a side stay assembly,- a lock stay assembly and actuator,- torque and slave links.

TMULDAI09-T01 LEVEL 2



UFD4200


MAIN LANDING GEAR DESCRIPTION - GENERALTMULDAI09-P01 LEVEL 2



UFD4200



MAIN FITTING

The main fitting includes:- the main barrel,- the drag stay,- the cross tube,- the aircraft attachment lugs.

It contains a diaphragm and tube assembly which formthe top of the shock absorber.A pin connects the diaphragm and the tube assembly.This pin is located in the two lateral holes in themain fitting, and contains the shock absorber chargingvalve.A gland housing assembly, at the bottom end of themain fitting, seals the joint between the main fittingand the sliding tube.A spare seal activating valve can isolate the bottomgland seals if a leak occurs.




UFD4200


MAIN LANDING GEAR DESCRIPTION - MAIN FITTING(TOP CHARGING VALVE ASSEMBLY - SPARE SEAL ACTIVATING VALVE)

TMULDAI09-P02 LEVEL 2



UFD4200



SLIDING TUBE/AXLE

The sliding tube moves in the main fitting and is aprimary component of the shock absorber.The axle and the sliding tube are part of same assembly.The second stage inflation valve of the shock absorberis on the sliding tube.




UFD4200


MAIN LANDING GEAR DESCRIPTION - SLIDING TUBE/AXLETMULDAI09-P03 LEVEL 2



UFD4200



ACTUATING CYLINDER

The MLG actuating cylinder is installed on the mainfitting at the piston rod end. Two lugs attach thebody to the wing rear spar.When it is hydraulically supplied:

- the piston rod extends to retract the MLG,- the piston rod retracts to extend the MLG.

SIDE STAY ASSEMBLY

The main components of the side stay assembly are:- a basic side stay,- a lock stay,- a lock stay actuator,- two lock springs,- the proximity sensors and their relatedtargets.

The lock springs move the lock stay to an overcenterposition during the extension cycle.

LOCK STAY

The lock stay provides an overcenter stop and ageometric lock of the landing gear.

LOCK STAY ACTUATOR

During MLG extension the two lock stay actuator portsare open to return; a restritor controls the rate ofMLG extension.It is pressurized to extend during MLG door closureuntil hydraulic pressure on the door close line isreleased.During MLG retraction, the hydraulic fluid retractsthe piston which opens the overcentered lock, to foldthe side stay and the lock stay against the locksprings.

TORQUE LINKS/SLAVE LINK

The torque links align the main fitting and the slidingtube, but let vertical movement between the partsoccur.The slave link is mounted at the rear.

TORQUE LINK DAMPER

The torque link damper is a spring centered, two wayhydraulic unit, which has its own hydraulic reservoir.Its function is to decrease the landing vibrationsthrough the torque links.




UFD4200


TMULDAI09-P04 LEVEL 2

MAIN LANDING GEAR DESCRIPTION - ACTUATING CYLINDER - SIDE STAY ASSEMBLY - LOCK STAYLOCK STAY ACTUATOR - TORQUE LINKS/SLAVE LINK - TORQUE LINK DAMPER



UFD4200



TMULDAI09 LEVEL 2



UFD4200


32 - LANDING GEAR

32-12-00 LANDING GEAR AND DOORS - MAINLANDING GEAR DOORS DESCRIPTION

CONTENTS:GeneralMain DoorMain Landing Gear Door UplockHinged FairingFixed Fairing

TMULDCI03 LEVEL 2



UFD4200


LANDING GEAR AND DOORS - MAIN LANDING GEAR DOORS DESCRIPTION

GENERAL

Each main landing gear is enclosed by one door and twofairings:

- one main door,- one hinged fairing,- one fixed fairing.

MAIN DOOR

The main door is attached to the fuselage struture bytwo hinges and is operated by an hydraulic actuator.Attached to the forward end of the main door is thehydraulic actuator and an uplock roller which is usedto keep the main door in the closed position.Installed on the rear end of the main door are steps,used for access to the gear well compartment.Two ramps are installed on the inside of the main door.These ramps make sure that the gear does not catch onthe main door during a free-fall extension.Two proximity sensors and targets send the door openposition signal of the main door to the Landing GearControl and Interface Units (LGCIUs).

MAIN LANDING GEAR DOOR UPLOCK

The MLG door uplock is closed mechanically, lockingthe door in the closed position, and hydraulicallyopened, releasing the door during normal extension andretraction sequences. The uplock can also be openedmechanically in free fall extension and ground dooropening.

HINGED FAIRING

The hinged fairing is attached to the wing skin by asingle hinge and to the landing gear by an adjustabletie rod.The adjustable tie rod causes the hinged fairing tofollow the landing gear during the landing gearextension and retraction.

FIXED FAIRING

The fixed fairing is attached to the outboard side ofthe landing gear main fitting by two types ofattachment assembly.Two adjustable studs are installed on the front of themain fitting.Three rod ends are installed, one on the front of themain fitting and two on the rear of the main fitting.

TMULDCI03-T01 LEVEL 2



UFD4200


MAIN LANDING GEAR DOORS DESCRIPTIONTMULDCI03-P01 LEVEL 2



UFD4200



TMULDCI03 LEVEL 2



UFD4200


32 - LANDING GEAR

32-21-00 LANDING GEAR AND DOORS - NOSELANDING GEAR DESCRIPTION

CONTENTS:GeneralShock Strut AssemblyShock AbsorberActuating CylinderDrag Strut AssemblyLockstay AssemblyLockstay Downlock ActuatorSliding TubeRotating TubeTorque Link

TMULDBI01 LEVEL 2



UFD4200


LANDING GEAR AND DOORS - NOSE LANDING GEAR DESCRIPTION

GENERAL

The nose gear retracts forward into the fuselage, andthus favorably assisted by aerodynamic moments duringgear extension.The nose gear includes :

- a shock strut assembly,- a drag strut assembly,- a lockstay assembly,- a gear actuating cylinder,- nose wheel steering system components.

SHOCK STRUT ASSEMBLY

The shock strut assembly hangs on the structure fromtwo trunnions. It includes the shock absorber.

SHOCK ABSORBER

The shock absorber is an integral shock absorber filledwith hydraulic fluid and nitrogen through a singlestandard servicing valve at the upper part of the leg.It also includes the two centering cams which returnthe wheels to the centered position when the gear isextended.

ACTUATING CYLINDER

The actuating cylinder operates the nose gear duringretraction and extension sequences.

DRAG STRUT ASSEMBLY

The drag strut assembly consists of a forestay at thetop, a tubular arm at the bottom which areinterconnected by a universal joint. The uplock rolleris installed on the upper hinge pin of the universaljoint.

LOCKSTAY ASSEMBLY

The lockstay assembly provides an overcentered stopand a geometric lock of the nose gear. It includesboth systems downlock proximity detectors.On the ground, a safety pin locks the two arms of thelockstay.

LOCKSTAY DOWNLOCK ACTUATOR

The downlock actuator locks and unlocks both braceassemblies of the lockstay. It is assisted by twosprings.

SLIDING TUBE

The sliding tube includes the wheel axle. It isinclined 9 degrees forward, this design allows thewheels to return freely to the centered position.The two system proximity detectors provide signals forboth gear extended and wheel centered positions.The towing lug is designed to shear if the towing loadis more than the limit.

TMULDBI01-T01 LEVEL 2



UFD4200


NOSE LANDING GEAR DESCRIPTION - LOCKSTAY ASSEMBLYTMULDBI01-P01 LEVEL 2



UFD4200


LANDING GEAR AND DOORS - NOSE LANDING GEAR DESCRIPTION

ROTATING TUBE

The rotating tube is inside the shock strut. It isequipped with a pinion which transmits steering ordersfrom the steering actuating cylinder to the wheels.

TORQUE LINK

The torque link is installed on the rear. It connectsthe sliding tube to the rotating tube.

TMULDBI01 LEVEL 2



UFD4200


32 - LANDING GEAR

32-22-00 LANDING GEAR AND DOORS - NOSELANDING GEAR DOORS DESCRIPTION

CONTENTS:GeneralMain DoorsProximity DetectorsAft DoorsLeg Door

TMULDDI01 LEVEL 2



UFD4200


LANDING GEAR AND DOORS - NOSE LANDING GEAR DOORS DESCRIPTION

GENERAL

The doors of the nose landing gear include:- two main doors,- two aft doors,- one leg door.

MAIN DOORS

The two main doors are hydraulically operated. Thesetwo doors are connected mechanically to the aircraftby a linkage which has two control rods connected tothe same bellcrank.This bellcrank is installed at the roof of the landinggear well and is operated by one double-actingactuator.An uplock assembly latches the doors in the closedposition.

PROXIMITY DETECTORS

Two proximity detectors per door provide a signal itis in the open position (one per system).The doors must be in this position to permit the gearto operate.

AFT DOORS

The two aft doors are symmetrical and connected by anadjustable rod to the gear leg.These doors close the aft part of the nose gear wellwhen the gear is retracted.

LEG DOOR

The leg door is attached to the rear part of the gearleg.When the gear is retracted, this door closes off thearea through which the drag strut passes when the gearis extended.

TMULDDI01-T01 LEVEL 2



UFD4200


NOSE LANDING GEAR DOORS DESCRIPTIONTMULDDI01-P01 LEVEL 2



UFD4200



TMULDDI01 LEVEL 2



UFD4200


32 - LANDING GEAR

32-00-00 LANDING GEAR COMPONENTS

CONTENTS:NLG Shock AbsorberMLG Shock Absorber

TMULD1I02 LEVEL 2



UFD4200


LANDING GEAR COMPONENTS

NLG SHOCK ABSORBER

LOCATIONZONE: 711

DESCRIPTIONThe shock absorber is of the single chamber typewithout a separator piston and is double acting.The shock absorber is filled with hydraulic fluid andnitrogen through a single standard servicing valve inthe upper part of the leg. Calibration of the meteringdevices in the shock absorber is the same for thedifferent versions of the aircraft.Holes are included in the leg to show possible leaksfrom the dynamic seal of the shock absorber.It is possible to remove the shock absorber withoutdrainage of the hydraulic fluid.A placard bonded to the leg shows the filling curves.The shock absorber includes 2 centering cams, the lowercam is part of the plunger tube and the upper cam ispart of the sliding tube. When the shock absorber isfully extended the pressure of the nitrogen causes thecams to engage. The wheels then return automaticallyto the center position.

TMULD1I02-T01 LEVEL 2



UFD4200


TMULD1I02-P01 LEVEL 2

LANDING GEAR COMPONENTS - NLG SHOCK ABSORBER - CENTERING CAM



UFD4200



MLG SHOCK ABSORBER

LOCATIONZONE: 731, 741

DESCRIPTIONThe shock absorber is a telescopic oleo-pneumatic unitwhich includes the sliding tube. It is installed inthe main fitting to transmit the landing, take off andtaxiing loads to the wing.When the shock absorber is compressed, the load istransmitted to the hydraulic fluid and nitrogen gas.The shock absorber is a 2 stage unit and contains fourchambers:

- a first stage gas chamber contains gas at alow pressure and hydraulic fluid,

- a recoil chamber that contains hydraulic fluid,- a compression chamber that contains hydraulicfluid,

- a 2nd stage gas chamber that contains gas ata high pressure.

Primary control of the shock absorber recoil is:- the fluid flow from the recoil chamber intothe gas chamber,

- the fluid flow from the gas chamber intothe compression chamber.




UFD4200



LANDING GEAR COMPONENTS - MLG SHOCK ABSORBER



UFD4200



TMULD1I02 LEVEL 2



UFD4200


32 - LANDING GEAR

32-00-00 LANDING GEAR COMPONENTS

CONTENTS:LGCIUProximity DetectorsSafety ValveSelector Valve ManifoldHydraulic FusesMLG Actuating CylinderMLG Uplock BoxMLG Door Actuating CylinderMLG Door Uplock BoxNLG Actuating CylinderNLG Uplock BoxNLG Door Actuating CylinderNLG Door Uplock BoxCut-Out ValveVent ValvesDoor Bypass Valves

TMULD2I01 LEVEL 3

EFFECTIVITY 32-00-00 Page 1Apr 30/96


UFD4200



LGCIU

IDENTIFICATIONFIN: 5GA1 (LGCIU1), 5GA2 (LGCIU2)

LOCATIONZONE: 121 (LGCIU1), Rack 93VU122 (LGCIU2), Rack 94VU

DESCRIPTIONEach Landing Gear Control and Interface Unit (LGCIU)consists of an ARINC 600 4 MCU (Modular Concept Unit)case that contains:

- 7 Printed Circuit Boards (PCU),- an On Board Replaceable Memory Module (OBRM),- a Power Supply Unit (PSU).

PROXIMITY DETECTORS

IDENTIFICATIONFIN: See table

DESCRIPTIONThe proximity detector consists of:

- a proximity sensor,- a sensor target.

The proximity sensor uses the variable reluctanceprinciple and operates on the detection of ferrousmetals. In this application the ferrous metal sensortarget supplies the electrical signal.As the sensor target moves into or out of the proximitysensor’s actuation area it causes a change in theproximity sensor’s electrical property.

BE CAREFUL: If the aircraft is electrically suppliedand a piece of ferrous metal is set on theproximity sensor, a flight configurationcan be read by its associated system.




UFD4200


LANDING GEAR COMPONENTS - LGCIU - PROXIMITY DETECTORSTMULD2I01-P01 LEVEL 3



UFD4200



SAFETY VALVE

IDENTIFICATIONFIN: 49GA

LOCATIONZONE: 148

DESCRIPTIONThe safety valve is a single solenoid valve thatoperates independently of the LGCIUs.

CUT-VIEWSolenoid Energized:When energized, the safety valve is open.Solenoid De-energized:When de-energized, the safety valve shuts off thehydraulic pressure to the landing gear system when theairspeed signal from ADIRU 1 and 3 is greater than260 ±5 kts.




UFD4200



LANDING GEAR COMPONENTS - LANDING GEAR SAFETY VALVE



UFD4200



SELECTOR VALVE MANIFOLD

IDENTIFICATIONFIN: 2524GM

LOCATIONZONE: 148

DESCRIPTIONThe selector valve manifold assembly consists of:

- a manifold block, equipped with hydraulic pipeconnections, a restrictor valve and a checkvalve,

- a landing gear selector valve,- a landing gear door selector valve.

Each valve has two operating solenoids. Each solenoidhas two coil windings, one for each of the landinggear control sub-systems.Weight: 7,09 kg (15.62 lb).

HYDRAULIC FUSES

IDENTIFICATIONFIN: 2629GM, 2630GM

LOCATIONZONE: 148

DESCRIPTIONHydraulic fuses are installed in the open and closelines between the nose landing gear door actuator andthe landing gear door selector valve. They close theline in case of leakage downstream in case of a flowrate equal to or greater than 11 l/mn (2.91 USgal/mn).The hydraulic fuse is reset by depressurizing the greensystem reservoir or by opening the bleed screw.




UFD4200


LANDING GEAR COMPONENTS - HYDRAULIC FUSES - SELECTOR VALVE MANIFOLDTMULD2I01-P03 LEVEL 3



UFD4200



MLG ACTUATING CYLINDER

IDENTIFICATIONFIN: 2503GM (LH), 2504GM (RH)

LOCATIONZONE: 731 , 741

DESCRIPTIONIdentical for left-hand and right-hand installation.Weight: 29,8 kg (67.71 lb).

MLG UPLOCK BOX



DESCRIPTIONThe uplock is hung in the same for both the left orright-hand installations.The same applies for the left-hand and right-handactuators.Weight: 4,722 kg (10.412 lb).




UFD4200


LANDING GEAR COMPONENTS - MLG ACTUATING CYLINDER - MLG UPLOCK BOXTMULD2I01-P04 LEVEL 3



UFD4200



MLG DOOR ACTUATING CYLINDER



DESCRIPTIONThe actuator is suitable for left-hand and right-handinstallations.Weight: 6,601 kg (14.553 lb).

MLG DOOR UPLOCK BOX



DESCRIPTIONThe uplock box is suitable for left-hand and right-handinstallations.Weight: 4,38 kg (9.65 lb).




UFD4200


LANDING GEAR COMPONENTS - MLG DOOR ACTUATING CYLINDER - MLG DOOR UPLOCK BOXTMULD2I01-P05 LEVEL 3



UFD4200



NLG ACTUATING CYLINDER


LOCATIONZONE: 711

NLG UPLOCK BOX


LOCATIONZONE: 123




UFD4200


LANDING GEAR COMPONENTS - NLG ACTUATING CYLINDER - NLG UPLOCK BOXTMULD2I01-P06 LEVEL 3



UFD4200



NLG DOOR ACTUATING CYLINDER


LOCATIONZONE: 123

NLG DOOR UPLOCK BOX


LOCATIONZONE: 123




UFD4200


LANDING GEAR COMPONENTS - NLG DOOR ACTUATING CYLINDER - NLG DOOR UPLOCK BOXTMULD2I01-P07 LEVEL 3



UFD4200



CUT-OUT VALVE


LOCATIONZONE: 147

DESCRIPTIONShuts off the high pressure supply and connects theentire landing gear hydraulic system to the returncircuit during free fall extension.




UFD4200


LANDING GEAR COMPONENTS - CUT-OUT VALVETMULD2I01-P08 LEVEL 3



UFD4200



VENT VALVES

IDENTIFICATIONFIN: 2532GM (NLG), 2516GM (MLG)


DESCRIPTIONThere are two identical mechanically operated ventvalves in the landing gear free fall extension system.During landing gear free fall extension, operation ofthe vent valve connects door close and gear raise linesto the return circuit.




UFD4200


LANDING GEAR COMPONENTS - VENT VALVESTMULD2I01-P09 LEVEL 3



UFD4200



DOOR BYPASS VALVES

IDENTIFICATIONFIN: 2533GM (NLG), 2517GM (LH), 2518GM (RH)

LOCATIONZONE: 123, 147, 148

DESCRIPTIONEach bypass valve isolates its corresponding doorhydraulic actuator from the landing gear hydraulicsupply during ground opening of landing gear door(s).Weight: 0,88 kg (1.94 lb).




UFD4200


LANDING GEAR COMPONENTS - DOOR BYPASS VALVESTMULD2I01-P10 LEVEL 3



UFD4200



TMULD2I01 LEVEL 3



UFD4200


32 - LANDING GEAR

32-40-00 WHEELS AND BRAKES - BRAKE SYSTEMPRESENTATION

CONTENTS:Normal BrakingNormal Braking by Auto BrakeManual Normal BrakingInflight BrakingParking BrakeAlternate Braking with Anti-SkidAlternate Braking without Anti-SkidSelf Examination

TMULDZ101 LEVEL 1

EFFECTIVITYALL 32-40-00 Page 1

Feb 29/96


UFD4200


WHEELS AND BRAKE - BRAKES SYSTEM PRESENTATION

The four braking modes available depend on :- the hydraulic system,- the position of the A/SKID & N/W STRG switchand PARKING BRK control switch.

NORMAL BRAKING

Normal braking is obtained when :- the green high hydraulic pressure is available,- the A/SKID & N/W STRG switch is in the "ON"position,

- the PARKING BRK control switch is in the "OFF"position.

Electrical control is obtained :- through the pedals,- automatically : on the ground by the auto brakesystem or in flight when the landing gearcontrol lever is set to "UP".

No indicator of normal brake pressure is used.

NORMAL BRAKING BY AUTO BRAKE

Before landing, the crew can select one of the AUTOBRAKE modes to obtain the optimal deceleration ratecompatible with the length of the runway.Before take-off, MAX mode must be selected in case ofan aborted take-off.When a pushbutton deceleration rate is selected, the"ON" light comes on blue to indicate the positivearming of the auto brake mode.Braking begins when ground spoilers deployment ordersare present.The Braking and Steering Control Unit (BSCU) energizesthe selector valve allowing green pressure to supplythe brakes through the automatic selector and normalservovalves.The automatic reversible selector, when powered by thegreen hydraulic system cuts the yellow one.Depending on the deceleration rate and the anti-skidregulation, the BSCU regulates the pressure deliveredto each brake through the normally open normalservovalves.Wheels rotation speed and ADIRU data are supplied tothe BSCU for braking and anti-skid computation.When the aircraft deceleration reaches a given value,the "DECEL" green light comes on.

TMULDZ101-T01 LEVEL 1


Feb 29/96


UFD4200


BRAKE SYSTEM PRESENTATION - NORMAL BRAKING BY AUTOBRAKETMULDZ101-P01 LEVEL 1


Feb 29/96


UFD4200


WHEELS AND BRAKES - BRAKE SYSTEM PRESENTATION

MANUAL NORMAL BRAKING

Electrical braking orders are sent by the pedals tothe Braking and Steering Control Unit (BSCU).The BSCU energizes the selector valve allowing greenpressure to supply the brakes through the automaticselector and normal servovalves.The automatic reversible selector, when powered by thegreen hydraulic system cuts the yellow one.Depending on manual braking orders and anti-skidregulation, the BSCU regulates the pressure deliveredto each brake through the normally open servovalves.Wheel rotation speed, braking pressure and ADIRU dataare supplied to the BSCU for braking and anti-skidcomputation.



Feb 29/96


UFD4200


BRAKE SYSTEM PRESENTATION - MANUAL NORMAL BRAKINGTMULDZ101-P02 LEVEL 1


Feb 29/96


UFD4200



INFLIGHT BRAKING

In order to stop the main landing gear wheels rotationbefore entry into the landing gear bay, a preprogrammedbrake pressure is released to the normal brakes.When the landing gear control lever is set to "UP",the BSCU opens the selector valve and energizes theservovalves. The brake pressure is released either when the nosegear is no longer downlocked or three seconds afterthe "UP" selection.Furthermore, nose wheels are mechanically braked atthe end of the gear retraction cycle using brake bands.



Feb 29/96


UFD4200


BRAKE SYSTEM PRESENTATION - INFLIGHT BRAKINGTMULDZ101-P03 LEVEL 1


Feb 29/96


UFD4200



PARKING BRAKE

The parking brake system is hydraulically suppliedeither by yellow high pressure or by an accumulatorof 12 hours autonomy.The system needs either DC ground/flight bus or hotbus 1 electrical supply and uses segregated wiringroutes.When the parking brake system is activated, all otherbraking modes become electrically and hydraulicallyinoperative.Note that, as normal braking and auxiliary low pressurecontrol systems are not available, an ultimateemergency braking can be ensured by means of theparking brake system.

PARKING BRAKE ONWhen the parking brake handle is lifted and turned to"ON", the parking brake control valve is energized.The BSCU is informed that the parking brake system ison, which deactivates the other braking modes.Yellow pressure passes through the parking brakecontrol valve and reaches the dual shuttle valve.The dual shuttle valve moves, allowing alternate systemcircuit to be supplied by the parking brake system.Brakes are supplied through the normally open alternateservovalves.The pressure delivered to the left hand and right handbrakes as well as the brake accumulator pressure areindicated on the yellow pressure triple indicator.

PARKING BRAKE OFFWhen the parking brake handle is lifted and turned to"OFF", the parking brake control valve is energizedon the opposite way, the parking brake is reset andall the other braking modes are restored.The yellow brake accumulator can be pressurized bypressing the yellow electrical pump pushbutton switch.



Feb 29/96


UFD4200


BRAKE SYSTEM PRESENTATION - PARKING BRAKETMULDZ101-P04 LEVEL 1


Feb 29/96


UFD4200



ALTERNATE BRAKING WITH ANTI-SKID

The alternate braking with anti-skid associates theyellow high pressure with the anti-skid regulation.This mode is automatically obtained :

- in case of green pressure loss,- if a failure occurs on the normal braking systemduring operation or BSCU BITE test.

As the normal system becomes inoperative, the alternatebraking circuit is pressurized through the automaticselector.Orders are entered by the pedals and transmittedthrough an auxiliary low pressure control system tothe dual valve.The dual valve regulates the yellow braking pressure.The BSCU ensures the anti-skid regulation bycontrolling the normally open alternate servovalves.The braking pressure is read on the ACCU/PRESS tripleindicator.



Feb 29/96


UFD4200


BRAKE SYSTEM PRESENTATION - ALTERNATE BRAKING WITH ANTI-SKIDTMULDZ101-P05 LEVEL 1


Feb 29/96


UFD4200



ALTERNATE BRAKING WITHOUT ANTI-SKID

Alternate braking without anti-skid is different fromalternate braking with anti-skid in that there is noanti-skid regulation.The anti-skid regulation can be disconnected :

- either electrically (A/SKID & N/W STRG switchset to "OFF" or power supply failure),

- or hydraulically if the brake yellow pressureaccumulator only supplies the brakes.

Brake pressure has to be limited by the pilot to avoidwheel locking using ACCU/PRESS triple indicator.With the accumulator pressure only, a maximum of 7full brake pedal applications can be performed.



Feb 29/96


UFD4200


BRAKE SYSTEM PRESENTATION - ALTERNATE BRAKING WITHOUT ANTI-SKIDTMULDZ101-P06 LEVEL 1


Feb 29/96


UFD4200


SELF EXAMINATION

Which hydraulic system powers normal braking ?A - Green system.B - Yellow system.C - Blue system.

How is inflight braking initiated ?A - By setting the landing lever to the UP

position.B - By shock absorber extension.C - By auto brake deactivation.

In case of normal braking system failure, how isalternate braking applied ?

A - Automatically when the selector valve isde-energized.

B - Automatically through the automaticselector.

C - As soon as the brake pedals are pressedin.

How can the parking brake be hydraulically powered ?A - Only by yellow high pressure.B - Only by the brake accumulator.C - Either by yellow high pressure or by the

brake accumulator.

TMULDZ101 LEVEL 1


Feb 29/96


UFD4200


32 - LANDING GEAR

32-40-00 WHEELS AND BRAKES - BRAKE SYSTEMDESCRIPTION

CONTENTS:PedalsBrake Pedals XMTR UnitBSCUSelector ValveNormal ServovalveWheelsAutomatic SelectorAuxiliary Low Pressure Control SystemDual ValveDual Shuttle ValveAlternate ServovalveParking Brake Control ValveParking Brake Operated ValveAccumulator

TMULDZZ02 LEVEL 3



UFD4200


WHEELS AND BRAKES - BRAKE SYSTEM DESCRIPTION

PEDALS

The pedals give mechanical inputs to the brake pedaltransmitter unit for manual normal braking and to theauxiliary low pressure control system for alternatebraking.

BRAKE PEDALS XMTR UNIT

The brake pedal transmitter unit transforms themechanical input from the right and left pedals intoelectrical signals which are sent to the BSCU.

BSCU

The Braking and Steering Control Unit (BSCU) controlsnormal braking, auto braking as well as anti-skidoperation during normal and alternate braking.

SELECTOR VALVE

The selector valve is an on/off valve. When normalbraking is applied, the BSCU first energizes theselector valve, this allows full green pressure tosupply the normal servovalves.

NORMAL SERVOVALVES

The normal servovalve has a dual function: it regulatesbraking pressure, which depends on BSCU braking orders,and anti-skid control pressure delivered to the brakes.They are located on the main landing gear strut.

WHEELS

Each main wheel is equipped with multidisc carbonbrakes.Each main wheel rotation speed given by a tachometeris fed back to the BSCU for anti-skid computation.

AUTOMATIC SELECTOR

The automatic selector allows the pressurization ofeither normal brake systems or alternate brake systemsand preferential supply to the normal system.

AUXILIARY LOW PRESSURE CONTROL SYSTEM

The auxiliary low pressure control system transformsthe mechanical input from the left and right pedalsinto hydraulic pressure which controls the dual valve.

DUAL VALVE

The dual valve allows the operation of the alternatebraking system.

DUAL SHUTTLE VALVE

The dual shuttle valve selects either the alternatebraking system or the parking brake system.

TMULDZZ02-T01 LEVEL 3



UFD4200


BRAKE SYSTEM DESCRIPTIONTMULDZZ02-P01 LEVEL 3



UFD4200


WHEELS AND BRAKES - BRAKE SYSTEM DESCRIPTION

ALTERNATE SERVOVALVES

The alternate servovalves regulate only the anti-skidcontrol pressure.They are located on the rear pressure bulkhead abovethe main landing gear strut.

PARKING BRAKE CONTROL VALVE

The parking brake electrical control valve is operatedby the parking brake handle. It deactivates anti-skidand braking modes.

PARKING BRAKE OPERATED VALVE

The parking brake operated valve shuts off supply tothe alternate brake system to prevent leakage throughthe dual valve.

ACCUMULATOR

The accumulator is only used for braking. It is eitherpressurized by the yellow hydraulic system or by theyellow electric pump.

TMULDZZ02-T01 LEVEL 3



UFD4200


32 - LANDING GEAR

32-42-00 WHEELS AND BRAKES - AUTO BRAKESYSTEM DESCRIPTION/OPERATION

CONTENTS:Auto Brake ModesADIRSA/SKID & N/W STRG SwitchArmingActivationDisarmingSelf Examination

TMULDG902 LEVEL 3



UFD4200


WHEELS AND BRAKES - AUTO BRAKE SYSTEM DESCRIPTION/OPERATION

AUTO BRAKE MODES

The AUTO BRK panel is used to select the desireddeceleration rate of the system.MAX mode is normally selected for take-off: In theevent of an aborted take-off, maximum braking pressureis sent to the normal servovalves as soon as groundspoilers deployment order is present.MED or LO modes are selected for landing: Progressivepressure is sent to the brakes, for respectively 2 or4seconds after the ground spoilers deployment order.

ADIRS

The Air Data Inertial Reference System (ADIRS) signalsthe aircraft deceleration rate to the Braking andSteering Control Unit (BSCU) to be compared with theselected deceleration mode for braking computation.

A/SKID & N/W STRG SWITCH

The A/SKID & N/W STRG switch activates the anti-skidsystem and enables auto brake arming.ON: Anti-skid and nose wheel steering are availableand auto brake can be armed provided the green pressureis valid.If green pressure drops:

- Yellow pressure takes over automatically,anti-skid is available and nose wheel steeringis lost.

- Auto brake cannot be armed.OFF: Anti-skid, nose wheel steering and auto brake arelost.

ARMING

The auto brake system is armed if one of the threemode pushbuttons (LO, MED or MAX) is pressed in andthe following conditions are met:

- Green pressure available.- Anti-skid electrically powered.- No failure in the normal braking system.

The ON light comes on blue when the corresponding rateis armed.

ACTIVATION

The automatic braking system is activated by 2 of the3 ground spoiler extension signals coming from theSpoiler Elevator Computers (SECs).The DECEL light comes on green when actual aircraftdeceleration is 80 % of selected rate (LO and MEDmodes) or 0.27 g (MAX mode).

DISARMING

The auto brake is disarmed by:- Releasing the selected pushbutton out or,- Loss of one or more arming conditions or,- Applying sufficient force to the pedals whenauto brake is operating.

- Ground spoiler retraction.




UFD4200


AUTO BRAKE SYSTEM DESCRIPTION/OPERATIONTMULDG902-P01 LEVEL 3



UFD4200


SELF EXAMINATION

In which mode is progressive pressure sent to thebrakes, 2 seconds after ground spoiler deployment:

A - MAX mode.B - MED mode.C - LO mode.

What are the auto brake arming conditions?A - An AUTO BRK pushbutton pressed in, green

pressure and anti-skid powered and nofailure in normal braking system.

B - An AUTO BRK pushbutton pressed in,yellow pressure and anti-skid poweredand no failure in normal braking system.

C - An AUTO BRK pushbutton pressed in, greenpressure and anti-skid deactivated andno failure in normal braking system.

TMULDG902 LEVEL 3



UFD4200


32 - LANDING GEAR

32-42-00 WHEELS AND BRAKES - ANTI-SKIDFUNCTION

CONTENTS:PurposeBSCUPrincipleRegulationServovalvesADIRUSelf Examination

TMULD2004 LEVEL 3



UFD4200


WHEELS AND BRAKES - ANTI-SKID FUNCTION

PURPOSE

The anti-skid system gives the maximum brakingefficiency as it keeps each individual wheel at themaximum deceleration rate avoiding a skiddingconfiguration.

BSCU

The Braking and Steering Control Unit (BSCU) providesanti-skid control during normal and alternate brakingby either system 1 or 2 of the BSCU.System 1 and 2 have independent power supplies, andat each energization, the first system supplied takescontrol.If the two systems are supplied simultaneously system 1has priority and system 2 is in standby.

PRINCIPLE

The speed of each main gear wheel, given by atachometer, is compared with the aircraft speedsupplied by the Air Data Inertial Reference Units.A reference speed is determined by the BSCU from thelongitudinal deceleration given by Air Data InertialReference Units 1, 2 or 3 (ADIRU).When the speed of a wheel decreases below 0.87 timesthe reference speed, brake release orders are givento that wheel to maintain the wheel deceleration rateat that value.

REGULATION

The operational amplifier compares the calculatedreference speed with the speed of the deceleratingwheel.The operational amplifier supplies numerical valueswhich are converted into current to supply the coilof the normal and alternate servovalves in use toensure the anti-skid function.

SERVOVALVES

The normal and alternate servovalves are identical butconnected differently to the BSCU.While the two coils of the normal servovalve areconnected to system 1 and 2 respectively, only onecoil of the alternate servovalve is used.

ADIRU

The required reference speed during braking is directlyobtained from the average between the values from thethree Air Data Inertial Reference Units (ADIRUs).In case the ADIRU data is not valid, the referencespeed is equal to the maximum of either main landinggear wheel speeds. Aircraft deceleration is limitedto 1.7 m/s2 (5.6 ft/s2).

TMULD2004-T01 LEVEL 3



UFD4200


ANTI-SKID FUNCTIONTMULD2004-P01 LEVEL 3



UFD4200


SELF EXAMINATION

When does the BSCU provide anti-skid control?A - During normal and alternate braking.B - Only during normal braking.C - When the auto brake system has failed.

What happens when a wheel speed decreases below0.87 times the reference speed?

A - A brake release order is given to thewheels of the same gear.

B - A brake release order is given to therelated wheel.

C - A brake release order is given to allwheels.

TMULD2004 LEVEL 3



UFD4200


32 - LANDING GEAR

32-40-00 WHEELS AND BRAKES - BRAKEHYDRAULIC SYSTEM OPERATION

CONTENTS:Normal BrakingAlternate Braking with Anti-SkidAlternate Braking without Anti-SkidParking BrakeSelf Examination

TMULDGT05 LEVEL 3



UFD4200


WHEELS AND BRAKES - BRAKE HYDRAULIC SYSTEM OPERATION

The hydraulic braking architecture is shown with allcomponents. Note that only their main functions areshown.

NORMAL BRAKING

The hydraulic braking operation is identical forautomatic braking, manual braking and inflightbraking.Note that during inflight braking, anti-skid functionis inhibited by the BSCU.Normal braking and anti-skid regulation areelectrically controlled by the Braking and SteeringControl Unit.

OPERATION:The selector valve is energized.The automatic selector ensures the segregation of thetwo hydraulic systems and preferential supply of thenormal braking system.The throttle valve decreases the movement speed of theautomatic selector when the brake selector valve isde-energized.The normal brake servovalves supply a pressure whichdepends on the control current delivered by the BSCU.The manifold comprises the two servovalves, the twopressure transducers and the two hydraulic fuses.The hydraulic fuse stops the flow in the line in caseof leakage.Note that during the normal braking the automaticselector connects the alternate system to the yellowreturn manifold.During manual braking, the master cylinders providean artificial feel at the pedals.The brake system is ready to be supplied by thealternate system in case of normal braking failure.

TMULDGT05-T01 LEVEL 3



UFD4200


BRAKE HYDRAULIC SYSTEM OPERATION - NORMAL BRAKINGTMULDGT05-P01 LEVEL 3



UFD4200



ALTERNATE BRAKING WITH ANTI-SKID

The alternate braking with anti-skid associates yellowhigh pressure with anti-skid regulation.

OPERATION:The orders are entered through the pedals and anauxiliary low pressure hydraulic system transmits theorders via the master cylinders, to control thedistribution dual valve.The pressure from the dual valve is delivered to thebrakes through the dual shuttle valve and the alternateservovalves. It is indicated on the yellow pressuretriple indicator.The alternate brake servovalve manifold comprises twoalternate servovalves and two hydraulic fuses.The BSCU ensures the anti-skid regulation bycontrolling the related servovalve.The hydraulic fuse stops the flow in the line in caseof leakage.




UFD4200


BRAKE HYDRAULIC SYSTEM OPERATION - ALTERNATE BRAKING WITH ANTI-SKIDTMULDGT05-P02 LEVEL 3



UFD4200



ALTERNATE BRAKING WITHOUT ANTI-SKID

In case of alternate braking without antiskid thebrakes are supplied either by the yellow high pressureor the brake accumulator.When yellow high pressure is available, the brakes aresupplied through the alternate system and the returnlines are connected to the yellow return manifold.When the brakes are only supplied by the brakeaccumulator the return lines are shut off by theautomatic selector.

OPERATION:The orders are entered through the pedals only and anauxiliary low pressure hydraulic system transmits theorders via the master cylinders, to control thedistribution dual valve.The pressure from the dual valve is delivered to thebrakes through the dual shuttle valve and the alternateservovalves. It is indicated on the yellow pressuretriple indicator.




UFD4200


BRAKE HYDRAULIC SYSTEM OPERATION - ALTERNATE BRAKING WITHOUT ANTI-SKIDTMULDGT05-P03 LEVEL 3



UFD4200



PARKING BRAKE

The brakes are supplied either by the yellow highpressure manifold or the brake accumulator.

OPERATION:When the parking brake handle is set to the "ON"position, all the other braking modes and the anti-skidsystem are deactivated and all the return lines areshut off.The parking brake electrical control valve comprisesone electrical linear transmitter which operates thehydromechanical valve and a pressure limiter for thedual shuttle valve supply.The secondary slide valve of the automatic selectorisolates the return lines of the alternate brakeservovalves to prevent fluid leakage to the yellowreservoir.The parking brake operated valve shuts off the supplyto the alternate system to prevent leakage through thedual valve.




UFD4200


BRAKE HYDRAULIC SYSTEM OPERATION - PARKING BRAKETMULDGT05-P04 LEVEL 3



UFD4200


SELF EXAMINATION

What is the purpose of the hydraulic fuses?A - To stop the flow in case of leakage.B - To shut off the return lines.C - To separate the Normal from the

Alternate Servovalves.

Are the return lines shut off when the parkingbrake is applied?

A - No, they are always open.B - Yes, by the Automatic Selector.C - Yes, when braking is supplied by the

accumulator only.

Which component gives priority to the greenhydraulic system?

A - Brake Selector Valve.B - Throttle Valve.C - Automatic Selector.

TMULDGT05 LEVEL 3



UFD4200


32 - LANDING GEAR

32-47-00 WHEELS AND BRAKES - BRAKETEMPERATURE SYSTEM PRESENTATION

CONTENTS:PurposeTemperature SensorBrake Temperature Monitoring Unit (BTMU)Braking and Steering Control Unit (BSCU)

TMULDGOZZ LEVEL 1



UFD4200


WHEELS AND BRAKES - BRAKE TEMPERATURE SYSTEM PRESENTATION

PURPOSE

The system measures the brake temperature and indicatesthe values on the lower display unit of the ECAM.A warning is generated when the brake temperaturethreshold is exceeded.

TEMPERATURE SENSOR

Brake temperature is measured by one chromel-alumelthermocouple per brake.

BRAKE TEMPERATURE MONITORING UNIT

The Brake Temperature Monitoring Unit (BTMU) isequipped with two printed circuits to process the datafrom the thermocouples.After processing, the BTMU delivers a voltage whichvaries between 1V and 9V corresponding to a temperaturerange of 0 to 1000°C.

BRAKING AND STEERING CONTROL UNIT

The Braking and Steering Control Unit (BSCU) changesanalog signals from the monitoring unit into digitalsignals for temperature indication on the lower ECAMdisplay unit.The amber HOT light on the optional BRK FAN pushbuttoncomes on when the temperature threshold of any brakeis reached.

TMULDGOZZ-T01 LEVEL 1



UFD4200


BRAKE TEMPERATURE SYSTEM PRESENTATIONTMULDGOZZ-P01 LEVEL 1



UFD4200



TMULDGOZZ LEVEL 1



UFD4200


32 - LANDING GEAR

32-48-00 BRAKE COOLING SYSTEM PRESENTATION

CONTENTSPurposeControl and LogicBrake Fans

TMULDWW01 LEVEL 1



UFD4200


BRAKE COOLING SYSTEM PRESENTATION

PURPOSE

The brake fan system allows the brakes to be cooledin a short time period.

CONTROL AND LOGIC

The BRK FAN pushbutton is used to operate the fan whenthe landing gear is downlocked.

BRAKE FANS

The impeller creates a flow of air from the heat packto the exterior through the debris guard.Each fan includes a three phase type motor, an impellerand a shroud with a debris guard.

TMULDWW01-T01 LEVEL 1



UFD4200


BRAKE COOLING SYSTEM PRESENTATIONTMULDWW01-P01 LEVEL 1



UFD4200



TMULDWW01 LEVEL 1



UFD4200


32 - LANDING GEAR

32-42-00 WHEEL AND BRAKE ECAM PAGEPRESENTATION

CONTENTS:Wheel/Brake Release IndicationsAnti-Skid IndicationAuto Brake IndicationsAlternate Braking IndicationBrake Temperature Indications

TMULDA4ZZ LEVEL 1



UFD4200


WHEEL AND BRAKE ECAM PAGE PRESENTATION

The ECAM WHEEL page displays landing gear and doorpositions, as well as brake and steering indications.

WHEEL/BRAKE RELEASE INDICATIONS

The wheel and brake release indications are displayedas shown on the table below.

ANTI-SKID INDICATION

"A/SKID" indication appears amber in case of failureof Braking and Steering Control Unit system 1 andsystem 2 or when the anti-skid and nose wheel steeringswitch (A/SKID & N/W STRG) is set to "OFF".

AUTO BRAKE INDICATIONS

"AUTO BRK" (Green) : Steady when auto brake is armed.Flashing for 10 sec after autobrake disengagement.

"AUTO BRK" (Amber) : If arming conditions are not met.If a failure occurs with thesystem armed.

"MED", "LO" or "MAX" (Green) : Selected auto brakerate.

ALTERNATE BRAKING INDICATION

"ALTN BRK" indication appears if the braking systemis in alternate mode.During normal braking operation, if a master lever isset to OFF, normal braking is momentarily lost andalternate braking becomes operative.This to avoid any jerks during braking when theelectrical generator is shut down.

BRAKE TEMPERATURE INDICATIONS

The various brake temperature indications aredisplayed as shown on the table below.

TMULDA4ZZ-T01 LEVEL 1



UFD4200


WHEEL AND BRAKE ECAM PAGE PRESENTATIONTMULDA4ZZ-P01 LEVEL 1



UFD4200



TMULDA4ZZ LEVEL 1



UFD4200


32 - LANDING GEAR

32-42-00 WHEEL AND BRAKE SYSTEM WARNINGS

CONTENTS:Config Parking Brake ONBrakes HotAuto Brake FaultAnti Skid NWS FaultAnti Skid/NWS OffHydraulic Selector Valve FaultBraking And Steering Control Unit System 1 (2) Fault

TMULDB6ZZ LEVEL 3



UFD4200


TMULDB6ZZ-P01 LEVEL 3

WHEEL AND BRAKE SYSTEM WARNINGS



UFD4200


32 - LANDING GEAR

32-42-00 NORMAL BRAKING COMPONENTS

CONTENTS:BSCUBrake Selector ValveFilterAutomatic SelectorThrottle ValveManifold Normal Brake ServovalvesNormal Brake ServovalvesPressure TransducersHydraulic FusesBrake Pedal Transmitter UnitBrake Belts (optional)

TMULDBXZZ LEVEL 3

EFFECTIVITY 32-42-00 Page 1Jun 30/00


UFD4200


NORMAL BRAKING COMPONENTS

BSCU

IDENTIFICATIONFIN: 10GG

LOCATIONZONE: 122, Rack 94VU

DESCRIPTIONThe Braking and Steering Control Unit (BSCU) consistsof:

- four power supply units grouped two by two,- two identical sets of three boards which formsystems 1 and 2, each board is connected to anOn-Board Reprogrammable Module (OBRM),

- a rear interface in the form of twoU-shaped boards (around the connector)comprises the lightning protection and theswitching assemblies.

TMULDBXZZ-T01 LEVEL 3



UFD4200


NORMAL BRAKING COMPONENTS - BSCUTMULDBXZZ-P01 LEVEL 3



UFD4200



BRAKE SELECTOR VALVE


LOCATIONZONE: 146

DESCRIPTIONThe selector valve directs normal hydraulic pressure(green system) through the automatic selector to thenormal brake servovalve manifold.It is energized for normal braking purposes.

FILTER


LOCATIONZONE: 146

DESCRIPTIONA filter with a filtering capability of 15 micronsabsolute is installed between the delivery port of theselector valve and the automatic selector.The purpose of this filter is to protect the supplyof the normal servovalves downstream of the selectorvalve.




UFD4200


NORMAL BRAKING COMPONENTS - BRAKE SELECTOR VALVE - FILTERTMULDBXZZ-P02 LEVEL 3



UFD4200



AUTOMATIC SELECTOR


LOCATIONZONE: 148

DESCRIPTIONThe automatic selector supplies the brake system witheither the green (normal braking) or yellow (alternatebraking/parking brake) pressure.Under normal operating conditions it allows the greenhydraulic fluid to flow to the brakes and maintainsthe yellow hydraulic pressure on standby status.Should the green pressure drop below a predeterminedvalue, the selector automatically cuts off the greensupply and opens the passage to the yellow pressure.In addition, it shuts off the yellow system from thereturn line for parking brake application.




UFD4200


TMULDBXZZ-P03 LEVEL 3

NORMAL BRAKING COMPONENTS - AUTOMATIC SELECTOR



UFD4200



AUTOMATIC SELECTOR (CONTINUED)

CROSS SECTIONThe automatic selector includes a primary stage whichselects the system.It also includes a secondary stage used to cut off thereturn from the servovalves of the alternate system.




UFD4200


NORMAL BRAKING COMPONENTS - AUTOMATIC SELECTOR CROSS SECTIONTMULDBXZZ-P04 LEVEL 3



UFD4200



THROTTLE VALVE


LOCATIONZONE: 148

DESCRIPTIONThe throttle valve is installed on the green supplyport (A) of the automatic selector.It decreases the speed of movement of the main slidevalve of the selector when the brake selector valveis de-energized.




UFD4200


NORMAL BRAKING COMPONENTS - THROTTLE VALVETMULDBXZZ-P05 LEVEL 3



UFD4200



MANIFOLD NORMAL BRAKE SERVOVALVES



DESCRIPTIONThe manifold is equipped with two servovalves, twopressure transducers, two hydraulic fuses and onefilter on the supply line of the manifold.

NORMAL BRAKE SERVOVALVES

IDENTIFICATIONFIN: 15GG (WHEEL 1), 17GG (WHEEL 2), 16GG (WHEEL 3),18GG (WHEEL 4)


DESCRIPTIONThere are four servovalves, one for each brake.The brake servovalve supplies a pressure inverselyproportional to the current which passes through thecontrol coil used.




UFD4200


NORMAL BRAKING COMPONENTS - MANIFOLD NORMAL BRAKE SERVOVALVES - NORMAL BRAKE SERVOVALVESTMULDBXZZ-P06 LEVEL 3



UFD4200



NORMAL BRAKE SERVOVALVES (CONTINUED)

CROSS SECTIONThe current of the control coil in use (either system1 or 2) moves a flapper located between two jets.This modifies the sections of the fluid passage at thejets, and consequently the pressure in the controlchambers of the slide valve.With zero current, the supplied pressure is equal tothe pressure supplied to the servovalve.If there is no supply pressure, the servovalve connectsthe brake to the reservoir return system.




UFD4200


NORMAL BRAKING COMPONENTS - NORMAL BRAKE SERVOVALVES CROSS SECTIONTMULDBXZZ-P07 LEVEL 3



UFD4200



PRESSURE TRANSDUCERS

IDENTIFICATIONFIN: 11GG (WHEEL 1), 13GG (WHEEL 2),12GG (WHEEL 3), 14GG (WHEEL 4)


DESCRIPTIONThe normal brake pressure transducers are installedon the manifold of the normal brake servovalve, onedownstream of each servovalve.The integrated-logic transducer supplies a DC voltagebetween 1 and 5V for a pressure between 0 and 3000 psi(206 bars).The zero has been shifted to enable BITE testing.

HYDRAULIC FUSES

IDENTIFICATIONFIN: 2618GM (WHEEL 1), 2616GM (WHEEL 2),2617GM (WHEEL 3), 2619GM (WHEEL 4)


DESCRIPTIONA hydraulic fuse, installed between the brakeservovalve and the brake, stops the flow in the lineif the leakage exceeds 1.32 U.S. gal/mn (5 l/mn).The valve is reset when you depressurize the hydraulicsystems and when you open the bleed screw.




UFD4200


NORMAL BRAKING COMPONENTS - PRESSURE TRANSDUCERS - HYDRAULIC FUSESTMULDBXZZ-P08 LEVEL 3



UFD4200



BRAKE PEDAL TRANSMITTER UNIT


LOCATIONZONE: 121

DESCRIPTIONThe brake pedal transmitter unit transforms the pedalinput into four identical electrical voltages per sidewhich are sent to the BSCU for selector valveenergization.Any overtravel is absorbed by the spring rods whichactuate the levers of the transmitter unit.




UFD4200


NORMAL BRAKING COMPONENTS - BRAKE PEDAL TRANSMITTER UNITTMULDBXZZ-P09 LEVEL 3



UFD4200



BRAKE BELTS (OPTIONAL)

LOCATIONZONE: 124

DESCRIPTIONBrake belts stop the nose gear wheels at the end ofthe gear retraction cycle.

NOTE: Depending on the aircraft configuration, brakebands are removed and optionally re-installed.When removed, there will be no braking of thenose wheels which shall be allowed to spin downnaturally.




UFD4200


TMULDBXZZ-P10 LEVEL 3

NORMAL BRAKING COMPONENTS - BRAKE BELTS



UFD4200



TMULDBXZZ LEVEL 3



UFD4200


32 - LANDING GEAR

32-43-00 WHEELS AND BRAKES - ALTERNATEBRAKING COMPONENTS

CONTENTS:Hydraulic ReservoirMaster CylindersAlternate Dual ValveManifold Brake Alternate ServovalvesAlternate ServovalvesBraking Pressure TransducersHydraulic FusesHydraulic Pressure TransducerRelief Valve

TMULDDX09 LEVEL 3



UFD4200


WHEELS AND BRAKES - ALTERNATE BRAKING COMPONENTS

HYDRAULIC RESERVOIR


LOCATIONZONE: 122

DESCRIPTIONThe brake control hydraulic reservoir supplies themaster cylinders of the alternate system with hydraulicfluid to permit volume changes of the fluid andcompensate possible leakages.The reservoir is slightly pressurized by a springloaded piston: 22 psi (1,5 bar).Capacity: 3.05 cu. in. (50 cm3).

MASTER CYLINDERS


LOCATIONZONE: 122

DESCRIPTIONThere is one master cylinder for the LH side and onefor the RH side.They are used to control the distribution dual valveof the alternate brake system by displacement of fluid.They also give artificial feel at the pedals by meansof an internal spring and the load resulting from thepressure increase in the control circuit.

TMULDDX09-T01 LEVEL 3



UFD4200


ALTERNATE BRAKING COMPONENTS - HYDRAULIC RESERVOIR - MASTER CYLINDERSTMULDDX09-P01 LEVEL 3



UFD4200



ALTERNATE DUAL VALVE


LOCATIONZONE: 148

DESCRIPTIONThe alternate dual valve includes two independentpressure-reducing valves, one for each main gear.A master cylinder operates each valve.A transparent drain tube connected to the cover of thedual valve is used to check for possible presence ofwater.




UFD4200


ALTERNATE BRAKING COMPONENTS - ALTERNATE DUAL VALVETMULDDX09-P02 LEVEL 3



UFD4200



ALTERNATE DUAL VALVE CROSS SECTION

PEDAL RELEASEDEach pressure reducing valve includes a control pistonwhich operates a distribution slide valve through aspring R1 and a rocker arm.When the pedal is released, the yellow pressure at Ais shut off and the brake port C is connected to thereservoir return B.

PEDAL DEPRESSED/PRESSURE INCREASINGWhen the pedal is pushed in, the volume of fluid movedby the master cylinder causes the displacement of thepiston which then operates the rocker arm and the slidevalve: B is shut off and the pressure port A isconnected to the brake port C.

PEDAL DEPRESSED/PRESSURE REGULATIONIn balanced state, the pressure supplied is inproportion to the compression of the spring R1 andconsequently to the displacement of the control piston.The pressure increases in the control line as a resultof the compression of the return springs of the controlpiston.The delivery pressure depends on the control pistontravel and the control pressure.Maximum pressure delivered: 2537 psi (175 bars).




UFD4200


ALTERNATE BRAKING COMPONENTS - ALTERNATE DUAL VALVE CROSS SECTIONTMULDDX09-P03 LEVEL 3



UFD4200



MANIFOLD BRAKE ALTERNATE SERVOVALVES



DESCRIPTIONThe manifold is equipped with two servovalves, twohydraulic fuses and one filter on the supply line ofthe manifold.




UFD4200


ALTERNATE BRAKING COMPONENTS - MANIFOLD BRAKE ALTERNATE SERVOVALVESTMULDDX09-P04 LEVEL 3



UFD4200



ALTERNATE SERVOVALVES

IDENTIFICATIONFIN: 41GG (Wheel 1), 43GG (Wheel 2), 40GG (Wheel 3),42GG (Wheel 4)

LOCATIONZONE: 571 (Wheel 1 & 2), 671 (Wheel 3 & 4)

DESCRIPTIONOnly one coil is used for anti-skid control by system1 and 2 (pins E and F are not used).




UFD4200


ALTERNATE BRAKING COMPONENTS - ALTERNATE SERVOVALVESTMULDDX09-P05 LEVEL 3



UFD4200



BRAKING PRESSURE TRANSDUCERS

IDENTIFICATIONFIN: 62GG (RH MLG), 63GG (LH MLG)

LOCATIONZONE: 146

DESCRIPTIONTwo pressure transducers measure the pressure suppliedeither by the alternate brake distribution dual valveor the parking brake pressure limiter.The pressure transducers send the information to theBrake Yellow Pressure Triple Indicator in the cockpit.




UFD4200


TMULDDX09-P06 LEVEL 3

ALTERNATE BRAKING COMPONENTS - BRAKING PRESSURE TRANSDUCERS



UFD4200



HYDRAULIC FUSES


LOCATIONZONE: 571 (Wheel 1 & 2), 671 (Wheel 3 & 4)

DESCRIPTIONA hydraulic fuse, installed between the brakeservovalve and the brake, stops the flow in the lineif the leakage exceeds 1.32 U.S. gal/mn (5 l/mn).The valve is reset when you depressurize the hydraulicreservoir and when you open the bleed screw.




UFD4200


ALTERNATE BRAKING COMPONENTS - HYDRAULIC FUSESTMULDDX09-P07 LEVEL 3



UFD4200



HYDRAULIC PRESSURE TRANSDUCER

IDENTIFICATIONFIN: 3068GN

LOCATIONZONE: 148

DESCRIPTIONThe transducer is made of two main sections. The firstsection has the pressure-sensing element. It includesa diaphragm which is under hydraulic pressure. Thediaphragm causes a piezoresistive sensing element tooperate on the Wheatstone bridge principle, accordingto the pressure applied.The transducer is a sealed unit and no maintenance isnecessary or possible.The pressure transducer sends hydraulic pressure datato the Brake Yellow Pressure Triple Indicator foraccumulator pressure indication.

RELIEF VALVE


LOCATIONZONE: 148

DESCRIPTIONThe hydraulic thermal-pressure relief valve iscalibrated at 3436 psi (237 bars).It can be manually activated for accumulatordepressurization.




UFD4200


ALTERNATE BRAKING COMPONENTS - HYDRAULIC PRESSURE TRANSDUCER - RELIEF VALVETMULDDX09-P08 LEVEL 3



UFD4200



TMULDDX09 LEVEL 3



UFD4200


32 - LANDING GEAR

32-45-00 WHEELS AND BRAKES - PARKINGBRAKE COMPONENTS

CONTENTS:AccumulatorPressure GageCharging ValveParking Brake Electrical Control ValveParking Brake Operated ValveDual Shuttle Valve

TMULDEX02 LEVEL 3



UFD4200


WHEELS AND BRAKES - PARKING BRAKE COMPONENTS

ACCUMULATOR


LOCATIONZONE: 148

DESCRIPTIONThe brake yellow pressure accumulator is eitherpressurized by the hydraulic system or by the yellowelectric pump.Filling pressure:

- 1450 psi at 60°F (100 bars at 20°C).Volume of fluid:

- 164.8 cu.in. (2700 cm3), filled with nitrogen.

PRESSURE GAGE


LOCATIONZONE: 148

DESCRIPTIONThe pressure gage indicates the actual nitrogenpressure.

CHARGING VALVE


LOCATIONZONE: 148

DESCRIPTIONThe accumulator is equipped with a charging valve fornitrogen refilling if necessary.

TMULDEX02-T01 LEVEL 3



UFD4200


PARKING BRAKE COMPONENTS - ACCUMULATOR - PRESSURE GAGE - CHARGING VALVETMULDEX02-P01 LEVEL 3



UFD4200



PARKING BRAKE ELECTRICAL CONTROL VALVE


LOCATIONZONE: 148

DESCRIPTIONThe parking-brake electrical control-valve comprises:

- a linear transmitter which operates thehydromechanical valve,

- a pressure limiter for the dual shuttle valvesupply,

- a replaceable desiccant cartridge,- two thermal fuses.

THERMAL FUSESA thermal fuse protects each linear transmitter coilfrom overheat.It is possible to reset the fuse after removal of thetransparent cover.

DESICCANT CARTRIDGEA replaceable desiccant cartridge indicates thehumidity conditions. The cartridge is blue and becomespink when in contact with water.




UFD4200


PARKING BRAKE COMPONENTS - PARKING BRAKE ELECTRICAL CONTROL VALVETMULDEX02-P02 LEVEL 3



UFD4200



PARKING BRAKE OPERATED VALVE


LOCATIONZONE: 148

DESCRIPTIONThe parking brake operated valve, installed betweenthe brake automatic selector and the dual valve, shutsoff supply to the alternate brake system to preventleakage through the distribution dual valve.Parking brake pressure is delivered through port C.Pressure from the automatic selector is deliveredthrough port A.Port B is connected to the dual valve.




UFD4200


PARKING BRAKE COMPONENTS - PARKING BRAKE OPERATED VALVETMULDEX02-P03 LEVEL 3



UFD4200



DUAL SHUTTLE VALVE


LOCATIONZONE: 148

DESCRIPTIONThe dual shuttle valve includes two valves, one foreach main gear, installed in a single block adjacentto the alternate brake distribution dual valve.Each valve is used to select either the alternatesystem (E or/and D) (spring biased position) or theparking brake system (A), to supply the correspondinggear (C or/and B).




UFD4200


TMULDEX02-P04 LEVEL 3

PARKING BRAKE COMPONENTS - DUAL SHUTTLE VALVE



UFD4200



TMULDEX02 LEVEL 3



UFD4200


32 - LANDING GEAR

32-40-00 WHEEL AND BRAKE COMPONENTS

CONTENTS:Main Landing Gear WheelsMain Landing Gear TiresCarbon BrakesTachometersMain Landing Gear Drive TachometersAxle Wheel Adapter SleevesNose Landing Gear WheelsNose Landing Gear TiresNose Landing Gear Axle Sleeves

TMULDJX04 LEVEL 3



UFD4200


WHEEL AND BRAKE COMPONENTS

MAIN LANDING GEAR WHEELS


LOCATIONZONE: 731 (WHEEL 1 & 2), 741 (WHEEL 3 & 4)

DESCRIPTIONThe MLG wheels consist of two forged light alloyhalf-wheels attached together with high-tensile steelbolts and self-locking nuts.An O-ring seal is put between the two half-wheels.The wheel is equipped with :

- one standard inflating valve,- one bolt which you can replace by a valve withan incorporated pressure indicator (PSI type).

- six fuse plugs deflate the tire in the eventof excessive brake overheat and thus protectagainst tire burst because of excessivepressure.Melting point of the fuse plug: • first set, inside keys, 300°C (572°F),• second set, on wheel web, 183°C (361°F).

MAIN LANDING GEAR TIRES



TRAINING INFORMATION POINTSAlways use the appropriate tires on the wheels.The Braking and Steering Control Unit is set to useone diameter of main gear tire only (Refer to AMM).

WARNING: THE WHEEL TIRE ASSEMBLY WEIGHS APPROXIMATELY61 KG (133 LB). BE CAREFUL WHEN YOU INSTALLIT TO PREVENT INJURY TO PERSONS OR DAMAGE TOTHE WHEEL OR AXLE.

TMULDJX04-T01 LEVEL 3



UFD4200


WHEEL AND BRAKE COMPONENTS - MAIN LANDING GEAR WHEELSTMULDJX04-P01 LEVEL 3



UFD4200



CARBON BRAKES



DESCRIPTIONEach brake includes:

- a piston housing,- a carbon heat pack.

The piston housing has:- two independent hydraulic sets (normal andalternate) of 7 pistons,

- a bleeder for each of the two systems,- a half self-sealing coupling for each system,- a torque tube,- two wear indicators for the heat pack,- a brake temperature sensor.

Three bolts and nine pins attach the brake to the axleflange of the landing gear.Brake weight: 67 kg (147 lb).




UFD4200


WHEEL AND BRAKE COMPONENTS - CARBON BRAKESTMULDJX04-P02 LEVEL 3



UFD4200



CARBON BRAKES (CONTINUED)

BLEED VALVES(see following page).

WEAR PIN INDICATORSTwo wear pins give a visual indication of the overallwear of the heat pack without removal (Parking brakeapplied).For the minimum length X of the wear pin indicatorrefer to the AMM.




UFD4200


TMULDJX04-P03 LEVEL 3

WHEEL AND BRAKE COMPONENTS - BLEED VALVES - WEAR PIN INDICATORS



UFD4200



TACHOMETERS

IDENTIFICATIONFIN: 19GG (WHEEL 1), 21GG (WHEEL 2),20GG (WHEEL 3), 22GG (WHEEL 4)


DESCRIPTIONThe tachometers send wheel speed information.Each tachometer has two 200 tooth rings:

- 1 stationary ring associated to a coil and apermanent magnet,

- 1 ring driven by the wheel.The rotation of the wheel causes variations in theinduction frequency which are proportional to theangular speed (Frequency = 200 x angular speed).The variable frequency voltage supplied by thetachometer is sent to the Braking/Steering ControlUnit (BSCU).

MAIN LANDING GEAR DRIVE TACHOMETERS



AXLE WHEEL ADAPTER SLEEVES



TRAINING INFORMATION POINTEach wheel is installed on the axle with an axle sleeve.

CAUTION : WHEN YOU INSTALL THE SLEEVE, DO NOT FORGETTO TURN IT IN ORDER TO INSERT THE LOCATINGPEGS IN THE AXLE KEYWAYS, THEN PUT THERETAINER IN ITS GROOVE.




UFD4200


WHEEL AND BRAKE COMPONENTS - TACHOMETERS - MLG DRIVE TACHOMETERS - AXLE SLEEVESTMULDJX04-P04 LEVEL 3



UFD4200



NOSE LANDING GEAR WHEELS

IDENTIFICATIONFIN: 2659GM (WHEEL 9), 2660GM (WHEEL 10)

LOCATIONZONE: 711

DESCRIPTIONThe wheels consist of two forged half-wheels made oflight alloy.They are attached together with bolts and self-lockingnuts.An O-ring seal is put between the two half-wheels.The wheels have 3 ports which are equipped with :

- one standard inflating valve,- one overpressure relief valve,- one bolt which you can replace by a valve withan incorporated pressure indicator (PSI type).

Wheel weight: 15.95 kg (35 lbs), including hub cap.

NOSE LANDING GEAR TIRES

IDENTIFICATIONFIN: 2635GM (WHEEL 9), 2636GM (WHEEL 10)

LOCATIONZONE: 711

TRAINING INFORMATION POINTAlways use the appropriate tires on the wheels.

AXLE SLEEVES

LOCATIONZONE: 711

TRAINING INFORMATION POINTEach NLG wheel is installed on the axle with an axlesleeve.




UFD4200


TMULDJX04-P05 LEVEL 3

WHEEL AND BRAKE COMPONENTS - NLG WHEELS - AXLE SLEEVES



UFD4200



TMULDJX04 LEVEL 3



UFD4200


32 - LANDING GEAR

32-47-00 WHEELS AND BRAKES - BRAKETEMPERATURE SYSTEM COMPONENTS

CONTENTS:BTMUsTemperature Sensors

TMULDIX01 LEVEL 3



UFD4200


WHEELS AND BRAKES - BRAKE TEMPERATURE SYSTEM COMPONENTS

BTMUs

IDENTIFICATIONFIN: 3GW, 2GW

LOCALISATIONZONE: 731, 741

COMPONENT DESCRIPTIONThe Brake Temperature Monitoring Unit (BTMU) isequipped with two printed circuits required to:

- process the data from the temperature sensor,- compensate the thermocouple cold junction.

There is one BTMU per main gear.

TEMPERATURE SENSORS

IDENTIFICATIONFIN: 7GW, 5GW, 4GW, 6GW

LOCALISATION ZONE: 731, 731, 741, 741

COMPONENT DESCRIPTIONEach brake is equipped with a temperature sensor whichis of the chromel-alumel thermocouple type.It delivers a voltage which is proportional to thetemperature difference between the cold junction andthe hot junction.

TMULDIX01-T01 LEVEL 3



UFD4200


BRAKE TEMPERATURE SYSTEM COMPONENTS - BTMUs - TEMPERATURE SENSORSTMULDIX01-P01 LEVEL 3



UFD4200



TMULDIX01 LEVEL 3



UFD4200


32 - LANDING GEAR

32-48-00 WHEELS AND BRAKES - BRAKECOOLING SYSTEM COMPONENTS

CONTENTSFan MotorImpeller

TMULDFX01 LEVEL 3



UFD4200


WHEELS AND BRAKES - BRAKE COOLING SYSTEM COMPONENTS

FAN MOTOR

IDENTIFICATIONFIN: 7GS (WHEEL 1), 9GS (WHEEL 2), 8GS (WHEEL 3),10GS (WHEEL 4)


DESCRIPTIONThe three phase fan motor is installed in the wheelaxle, where an adaptor assembly holds it in position.Note that the tachometer drive shaft passes throughthe hollow shaft of the fan motor and the shroud drivesthe tachometer.

IMPELLER



DESCRIPTIONThe impeller creates a flow of air from the heat packto the exterior through the debris guard.

TMULDFX01-T01 LEVEL 3



UFD4200


BRAKE COOLING SYSTEM COMPONENTS - FAN MOTOR - IMPELLERTMULDFX01-P01 LEVEL 3



UFD4200



TMULDFX01 LEVEL 3



UFD4200


32 - LANDING GEAR

32-51-00 NOSE WHEEL STEERING SYSTEMPRESENTATION

CONTENTS:ControlsPedalsDisconnect PushbuttonBSCUActivationTowing Control LeverSelf Examination

TMULD1003 LEVEL 1



UFD4200


NOSE WHEEL STEERING SYSTEM PRESENTATION

The nose wheel steering system is hydraulically poweredand controlled by an electrical servomechanism fromthe cockpit via the Braking and Steering Control Unit(BSCU).

CONTROLS

Steering is controlled by two handwheels and the rudderpedals depending on aircraft speed. Their signals arealgebraically added if they are operatedsimultaneously.Steering angle speed limitation shown on the schematicbelow.

PEDALS

Steering orders from the pedals are sent to the BSCU,via the Elevator Aileron Computer which also receivesautopilot steering signals.The resulting signal is algebraically added to thehandwheel signals in the BSCU.

DISCONNECT PUSHBUTTON

When a rudder pedal disconnect pushbutton is pressedin, nose wheel steering by the pedals is disconnected.

NOTE: The disconnect pushbuttons are also used duringrudder ground check.

BSCU

The A/SKID & N/W STRG switch enables electrical powersupply of the BSCU which computes the steering orders.

ACTIVATION

Steering signals are sent to the hydraulic block whenthe arming conditions are met.The steering hydraulic block is powered by greenpressure if the nose gear doors are closed.

NOTE: Steering is lost after gear gravity extensionas the doors remain open.

TOWING CONTROL LEVER

A lever on the towing electrical box located on thenose landing gear enables the steering system to bedeactivated for towing purposes.With the control lever in towing position:

- The maximum towing angle is ± 95°,- The ECAM MEMO DISPLAY shows N WHEEL STEERDISC in green, which changes to amber ifone engine is running.

TMULD1003-T01 LEVEL 1



UFD4200


NOSE WHEEL STEERING SYSTEM PRESENTATIONTMULD1003-P01 LEVEL 1



UFD4200


SELF EXAMINATION

What is the maximum nose wheel steering angleobtained by the handwheels?

A - ± 6°.B - ± 74°.C - ± 95°.

Is nose wheel steering available after a landinggear gravity extension ?

A - Yes.B - No.

TMULD1003 LEVEL 1



UFD4200


32 - LANDING GEAR

32-51-00 NOSE WHEEL STEERING SYSTEMDESCRIPTION/OPERATION

CONTENTS:Rotating JointSelector ValveCheck Valve/FilterServovalveAdjustable DiaphragmCheck ValvesBypass ValveAnti-Shimmy ValvesSteering ActuatorAccumulatorBleed ScrewOperationSelf Examination

TMULDGS04 LEVEL 3



UFD4200


NOSE WHEEL STEERING SYSTEM DESCRIPTION/OPERATION

ROTATING JOINT

The rotating joint is installed co-axially with respectto the landing gear retraction axis and provideshydraulic power supply when the gear is extended.When the gear starts to retract, the rotating jointcuts the hydraulic power supply.

SELECTOR VALVE

When the selector valve is energized the pressure isapplied to the servovalve via the slaved valve.

CHECK VALVE/FILTER

A 40 micron filter and a check valve are installed inthe hydraulic power supply line.

SERVOVALVE

The servovalve is of the deflection-jet type. It isequipped with a Linear Variable DifferentialTransducer (LVDT) sensor which detects the positionof the slide valve.The LVDT provides position feedback for the steeringcontrol.

ADJUSTABLE DIAPHRAGM

The ajustable diaphragms are used to adjust the flowto each actuating cylinder chamber and consequentlythe wheel steering speed.

CHECK VALVES

Two check valves ensure the distribution of fluid fromthe accumulator to the chamber of the steering actuator.

BYPASS VALVE

The bypass valve interconnects the two chambers of the steeringactuator in the event of hydraulic system depressurization.The bypass valve opens if the pressure exceeds 273 bars(4000 psi).

ANTI-SHIMMY VALVES

There is one anti-shimmy valve per steering actuator chamber.

STEERING ACTUATOR

The steering actuator drives the rotating tube, whichis part of the nose landing gear structure, via arack-and-pinion assembly.

ACCUMULATOR

The anti-shimmy accumulator supplies pressurized fluidin case of cavitation in one of the two chambers ofthe steering actuator.The accumulator can supply fluid pressurized up to 15bars (220 psi).

BLEED SCREW

A bleed screw allows bleeding and depressurization ofthe hydraulic block.T

MULDGS04-T01 LEVEL 3



UFD4200


NOSE WHEEL STEERING SYSTEM DESCRIPTION/OPERATION - DESCRIPTIONTMULDGS04-P01 LEVEL 3



UFD4200


NOSE WHEEL STEERING SYSTEM DESCRIPTION/OPERATION

OPERATION

When the nose gear is extended and the nose gear doorsare closed, the hydraulic block is pressurized.When the MLG is compressed, both chambers of thesteering actuator are supplied and the nose wheelsservoed to an angle of 0º.Depending on the BSCU reference speed and the nosewheel steering orders, the nose wheels are steered.

TMULDGS04-T02 LEVEL 3



UFD4200


TMULDGS04-P02 LEVEL 3

NOSE WHEEL STEERING SYSTEM DESCRIPTION/OPERATION - OPERATION



UFD4200


SELF EXAMINATION

What is the purpose of the accumulator?A - To compensate a complete pressure loss.B - To dampen rapid movements.C - To supply hydraulic pressure in case of

cavitation.

What is the purpose of the bypass valve?A - To interconnect the two chambers of the

steering actuator.B - To apply hydraulic pressure to the

servovalve.C - To bypass the servovalve in case of BSCU

failure.

What are the adjustable diaphragms used for?A - To ensure self centering of the nose

gear.B - To adjust the nose wheel steering speed.C - To adjust the rate of depressurization

in the hydraulic block.

TMULDGS04 LEVEL 3



UFD4200


32 - LANDING GEAR

32-42-00 NOSE WHEEL STEERING ECAM PAGEPRESENTATION

CONTENTS:Steering Indication

TMULDB401 LEVEL 1



UFD4200


NOSE WHEEL STEERING ECAM PAGE PRESENTATION

The ECAM WHEEL page displays landing gear and doorpositions, as well as brake and steering indications.

STEERING INDICATION

The "STEERING" indication appears amber in case ofgreen hydraulic failure, nose wheel steering failureor when the anti-skid and nose wheel steering (A/SKID& N/W STRG) switch is set to "OFF".

TMULDB401-T01 LEVEL 1



UFD4200


NOSE WHEEL STEERING ECAM PAGE PRESENTATIONTMULDB401-P01 LEVEL 1



UFD4200



TMULDB401 LEVEL 1



UFD4200


32 - LANDING GEAR

32-42-00 NOSE WHEEL STEERING SYSTEMWARNINGS

CONTENTS:ANTI SKID/NWS FaultANTI SKID/NWS OffHyd Sel FaultBSCU Sys 1 (2) FaultN.W. Steer Fault

TMULDC601 LEVEL 3



UFD4200


TMULDC601-P01 LEVEL 3

NOSE WHEEL STEERING SYSTEM WARNINGS



UFD4200


32 - LANDING GEAR

32-51-00 NOSE WHEEL STEERING SYSTEMCOMPONENTS

CONTENTS:Electrical Box

TMULDKX02 LEVEL 2



UFD4200


NOSE WHEEL STEERING SYSTEM COMPONENTS

ELECTRICAL BOX

IDENTIFICATIONFIN: 5GC

LOCATIONZONE: 711

DESCRIPTIONThe electrical box is used to disengage the steeringcontrol system when the aircraft is being towed. Inthe disengaged position the handle must be secured bya pin.In addition, a light indicates when the PARKING BRAKEis set to the "ON" position. A LIGHT TEST pushbuttonallows this light to be tested.

TMULDKX02-T01 LEVEL 2



UFD4200


TMULDKX02-P01 LEVEL 2

NOSE WHEEL STEERING SYSTEM COMPONENTS - ELECTRICAL BOX



UFD4200



TMULDKX02 LEVEL 2



UFD4200


32 - LANDING GEAR

32-51-00 NOSE WHEEL STEERING SYSTEMCOMPONENTS

CONTENTS:BSCUHandwheel Transmitter UnitFeedback SensorsHydraulic Control UnitRotating Joint

TMULDLX02 LEVEL 3



UFD4200



BSCU


LOCATIONZONE: 122

DESCRIPTIONThe Braking and Steering Control Unit (BSCU) consistsof:

- four power supply units grouped two by two,- two identical sets of three boards which formthe systems 1 and 2, each board is connectedto an On-Board Reprogrammable Module (OBRM),

- a rear interface in the form of two U-shapedboards (around the connector) comprises thelightning protection and the switchingassemblies.

HANDWHEEL TRANSMITTER UNIT

IDENTIFICATIONFIN: 1GC, 2GC


DESCRIPTIONEach handwheel activates a transmitter unit with4 potentiometers.In addition, it includes a pushbutton switch for thedisconnection of the nose wheel steering controlthrough the rudder pedals.

TMULDLX02-T01 LEVEL 3



UFD4200


NOSE WHEEL STEERING SYSTEM COMPONENTS - BSCU - HANDWHEEL TRANSMITTER UNITTMULDLX02-P01 LEVEL 3



UFD4200



FEEDBACK SENSORS

IDENTIFICATIONFIN: 3GC, 4GC

LOCATIONZONE: 711

DESCRIPTIONThe nose wheel steering feedback sensor is of theRotary Variable Differential Transducer (RVDT) type.It consists of a reduction gearbox and a sensor box.The sensor box transmits the rotating tube positionto the sensor box which sends information to the BSCUfor steering position monitoring.The knob, with an internal lockpin, locks the gearboxin the neutral position (0 degree) before installationof the sensor box.

HYDRAULIC CONTROL UNIT

IDENTIFICATIONFIN: 6GC

LOCATIONZONE: 711

DESCRIPTIONThe hydraulic control unit mainly consists of:

- a selector valve,- a servovalve,- an accumulator,- a filter and valves.

It is hydraulically supplied from the nose landinggear doors close line, through the rotating joint, andelectrically connected to the BSCU.It supplies the steering cylinders according to theelectrical signals.




UFD4200


NOSE WHEEL STEERING SYSTEM COMPONENTS - FEEDBACK SENSORS - HYDRAULIC CONTROL UNITTMULDLX02-P02 LEVEL 3



UFD4200



ROTATING JOINT

IDENTIFICATIONFIN:2526GM (NLG LEG ASSY)

LOCATIONZONE: 711

DESCRIPTIONThe rotating joint mainly consists of:

- a fixed part fitted with a liner and a leverfor the attachment to the aircraft structure,

- a moving part fitted with a shaft and a platefor the attachment to the NLG leg hinge pin.

It supplies the steering hydraulic control unit whenthe leg is downlocked and stops the fluid flow whenthe leg is in another position.




UFD4200


NOSE WHEEL STEERING SYSTEM COMPONENTS - ROTATING JOINTTMULDLX02-P03 LEVEL 3



UFD4200



TMULDLX02 LEVEL 3



UFD4200


32 - LANDING GEAR

32-42-00 BRAKING AND STEERING - BSCUCONTROL INTERFACES

CONTENTS:ADIRUsSECsLGCIUsELACsBTMUsTachometersLGCIUsPack Controllers

TMULDGV0C LEVEL 3



UFD4200


BRAKING AND STEERING - BSCU CONTROL INTERFACES

ADIRUs

The aircraft reference speed for nose wheel steeringand anti-skid functions is obtained by processing theinertial deceleration from the Air Data InertialReference Units (ADIRUs).

SECs

Two of the three ground spoilers extended signalscoming from the Spoiler Elevator Computers (SECs) mustbe present to enable automatic braking.

LGCIUs

Inputs from both Landing Gear Control and InterfaceUnits (LGCIUs) serve for braking and nose wheelsteering functions control logic.

ELACs

The link between the BSCU and the Elevator AileronComputer (ELAC) serves for nose wheel steering purposeswith orders coming from rudder pedals and autopilot.

BTMUs

The BSCU changes analog signals from the BrakeTemperature Monitoring Units (BTMUs) into digital onesfor temperature indication on the lower ECAM displayunit.

TACHOMETERS

Tachometers send wheel speed values to the BSCUenabling reference speed computation and also to theSpoiler Elevator Computers for ground spoilersextension logic.

LGCIUs

Landing Gear Control and Interface Units receive wheelspeed indications. These signals are used for BITE inhibition.

PACK CONTROLLERS

After wheel speed computation the BSCU energizes wheelspeed relays.The latter send a signal to the Pack Controllers forpack ram air inlet operation during take-off andlanding phases.

TMULDGV0C-T01 LEVEL 3



UFD4200


BRAKING AND STEERING - BSCU CONTROL INTERFACESTMULDGV0C-P01 LEVEL 3



UFD4200



TMULDGV0C LEVEL 3



UFD4200


32 - LANDING GEAR

32-42-00 BRAKING AND STEERING - BSCUARCHITECTURE AND MONITORINGINTERFACES

CONTENTS:ArchitectureMonitoring

TMULDGUZZ LEVEL 3



UFD4200


BRAKING AND STEERING - BSCU ARCHITECTURE AND MONITORING INTERFACES

ARCHITECTURE

The Braking/Steering Control Unit (BSCU) is made upof two identical sets of three boards which form thesystems 1 and 2.At each energization the system supplied first takescontrol.If there is a disagreement between the control and themonitoring channels, the corresponding system isdisengaged and the system in standby takes over.

TMULDGUZZ-T01 LEVEL 3



UFD4200


BSCU ARCHITECTURE AND MONITORING INTERFACES - ARCHITECTURETMULDGUZZ-P01 LEVEL 3



UFD4200


BRAKING AND STEERING - BSCU ARCHITECTURE AND MONITORING INTERFACES

MONITORING

CFDIUThe BSCU sends BITE data to the Centralized FaultDisplay System (CFDS) by a bi-directional ARINC 429link. This link permits transmission of the failuremessages.

SDACThe System Data Acquisition Concentrators (SDACs)receive ARINC 429 bus signals for acquirement andprocessing of all the data necessary for the generationof warnings.

FDIUThe Flight Data Interface Unit collects braking systemdata (braking pressure, braking pedal position,autobrake status) in order to send them to the flightdata recorder.

DMUThe Display Management Unit receives maintenance datafor reports used in preventive maintenance. The DisplayManagement Unit (DMU) is a computer of the AircraftIntegrated Data System (AIDS)(as an option, AIDS maynot be installed).

FMGCThe BSCU sends 4 availability discretes to the FlightManagement and Guidance Computers (FMGCs). This is tomeet the safety requirements of a category 3B landing.

TMULDGUZZ-T02 LEVEL 3



UFD4200


BSCU ARCHITECTURE AND MONITORING INTERFACES - MONITORINGTMULDGUZZ-P02 LEVEL 3



UFD4200



TMULDGUZZ LEVEL 3



UFD4200


32 - LANDING GEAR

32-49-00 TIRE PRESSURE INDICATING SYSTEMPRESENTATION

CONTENTS:FunctionDescriptionSelf Examination

TMULD1Q04 LEVEL 1



UFD4200


TIRE PRESSURE INDICATING SYSTEM PRESENTATION

FUNCTION

The function of the Tire Pressure Indicating Systemis to supply:

- pressure information, for each tire, to bedisplayed on the ECAM,

- warnings when pressure in one or more tiresdoes not agree with the specified pressure.

The warning functions of the system are as follows:- to show that the absolute pressure of any tireis lower than a given value,

- to tell the flight crew when the pressuredifference between 2 tires installed on thesame wheel axle is above a given value,

The indication becomes amber in case of abnormalpressure.

DESCRIPTION

The Tire Pressure Indicating System has a sensor anda transmitter for each wheel, and includes a computer:the Tire Pressure Indicating Unit (TPIU).The system includes:

- a sensor which measures the pressure of eachtire,

- a rotating mechanism which transmits theelectrical pressure signal from the wheel tothe wheel axle.It includes a rotatingtransformer and an integrated electronicmodule,

- a computer TPIU (Tire Pressure IndicatingUnit).

TMULD1Q04-T01 LEVEL 1



UFD4200


TIRE PRESSURE INDICATING SYSTEM PRESENTATIONTMULD1Q04-P01 LEVEL 1



UFD4200


SELF EXAMINATION

Where is the Tire Pressure Indication displayed ?A - On a tire and brake indicator.B - On ECAM.C - No indication.

TMULD1Q04 LEVEL 1



UFD4200


32 - LANDING GEAR

32-49-00 TIRE PRESSURE INDICATING SYSTEMDESCRIPTION/OPERATION

CONTENTS:PurposePressure TransducerRotating MechanismElectronic ModuleRotating TransformerDetection UnitInterfacesSelf Examination

TMULDGQ04 LEVEL 3



UFD4200


TIRE PRESSURE INDICATING SYSTEM DESCRIPTION/OPERATION

PURPOSE

The Tire Pressure Indicating System (TPIS)continuously monitors the absolute pressure of eachindividual tire and provides cockpit indications andwarnings.

PRESSURE TRANSDUCER

A pressure transducer installed in the wheel rimmeasures the pressure of each tire.The pressure transducer gives a DC signal from 0 to100mV in proportion to the pressure.

ROTATING MECHANISM

The rotaring mechanism serves to transmit the tirepressure signal from the wheel to the axle.The rotating transformer also provides the necessarypower supply for the electronic module and the pressuretransducer in form of a 3125Hz signal.

ELECTRONIC MODULE

The integrated electronic module amplifies the signalfrom the pressure transducer and changes the voltageinto frequency by means of a converter.The voltage to frequency converter gives a signal whichvaries from 50 to 100kHz for a pressure range from 0to 300psi.

ROTATING TRANSFORMER

The rotating transformer transmits the tire pressurevalue from the wheel to the detection unit.

DETECTION UNIT

The detection unit comprises a microprocessor whichprovides data processing and distribution of each tirepressure including normal and abnormal pressuresignals for ECAM indication and CFDS monitoring.The TPIS detection unit permanently performs a testof the unit itself, the rotating mechanism and thepressure transducer. The test is only stopped for dataprocessing and distribution.

INTERFACES

The signal from the Landing Gear Control and InterfaceUnit (LGCIU) is used to change the tire pressurethreshold for on ground or in flight warnings.Note that tire pressure warnings are only memorizedby the BITE when at least one engine is running toprevent false warnings during wheel change.

TMULDGQ04-T01 LEVEL 3



UFD4200


TIRE PRESSURE INDICATING SYSTEM DESCRIPTION/OPERATIONTMULDGQ04-P01 LEVEL 3



UFD4200


TIRE PRESSURE INDICATING SYSTEM DESCRIPTION/OPERATION

SELF EXAMINATION

What signal is delivered by the pressure transducer?A - A DC signal which depends on the tire

pressure.B - A frequency signal which depends on the

tire pressure.C - A pneumatic signal equal to the tire

pressure.

What is the rotating mechanism used for?A - To change the pressure voltage into a

frequency signal.B - To transmit the tire pressure signal

from the wheel to the axle.C - To perform the permanent test of the

system.

TMULDGQ04 LEVEL 3



UFD4200


32 - LANDING GEAR

32-49-00 TIRE PRESSURE INDICATING SYSTEMWARNINGS

CONTENTS:Tire Lo Pr

TMULDBQ04 LEVEL 3



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TIRE PRESSURE INDICATING SYSTEM WARNINGSTMULDBQ04-P01 LEVEL 3



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32 - LANDING GEAR

32-49-00 TIRE PRESSURE INDICATING SYSTEMCOMPONENTS

CONTENTS:Tire Pressure Indicating UnitMLG Transmission UnitMLG Pressure TransducerNLG Transmission UnitNLG Pressure Transducer

TMULDHX04 LEVEL 3



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TIRE PRESSURE INDICATING SYSTEM COMPONENTS

TIRE PRESSURE INDICATING UNIT

IDENTIFICATIONFIN: 2GV

LOCATIONZONE: 122

COMPONENT DESCRIPTIONThe TPIS detection unit is of the 3 Modular ConceptUnit (MCU) size and is connected to the aircraft wiringthrough an ARINC 600 connector, size 1.The detection unit performs a permanent test which isonly stopped for processing of the following threefunctions :

- pressure measurement,- data distribution,- maintenance.

TMULDHX04-T01 LEVEL 3



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TIRE PRESSURE INDICATING SYSTEM COMPONENTS - TIRE PRESSURE INDICATING UNITTMULDHX04-P01 LEVEL 3



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MLG TRANSMISSION UNIT

IDENTIFICATIONFIN: 7GV (WHEEL 1), 9GV (WHEEL 2), 6GV (WHEEL 3),

8GV (WHEEL 4)

LOCATIONZONE: 731 (LH MLG), 741 (RH MLG)

COMPONENT DESCRIPTIONThe rotating mechanism includes :

- a rotating transformer which transmits theelectrical power (3125Hz signal) to supply theelectronic circuits and the pressure transducerinstalled on the wheel. It transmits also thetire pressure value from the wheel to the axle.The frequency varies from 50kHz to 100kHz.

- an integrated electronic module which amplifiesthe DC signal from the pressure transducer andconverts the voltage into frequency (50kHz to100kHz range), before the signal is applied tothe rotating transformer.

MLG PRESSURE TRANSDUCER

IDENTIFICATIONFIN: 13GV (WHEEL 1), 15GV (WHEEL 2), 12GV (WHEEL 3),

14GV (WHEEL 4)

LOCATIONZONE: 731 (LH MLG), 741 (RH MLG)

COMPONENT DESCRIPTIONThe pressure transducer is installed in a supportattached to the wheel rim. It is of the piezoresistivestrain-gage type. An external voltage source suppliesthis transducer which gives a DC signal from 0 to 100mVin proportion to the pressure. A four-wire, shieldedand twisted cable is connected to the rotatingmechanism.




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TPIS COMPONENTS - MLG TRANSMISSION UNIT - MLG PRESSURE TRANSDUCERTMULDHX04-P02 LEVEL 3



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NLG TRANSMISSION UNIT

IDENTIFICATIONFIN: 4GV (WHEEL 9), 5GV (WHEEL 10)

LOCATIONZONE: 711

NLG PRESSURE TRANSDUCER

IDENTIFICATIONFIN: 10GV (WHEEL 9), 11GV (WHEEL 10)

LOCATIONZONE: 711




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TPIS COMPONENTS - NLG TRANSMISSION UNIT - NLG PRESSURE TRANSDUCERTMULDHX04-P03 LEVEL 3



UFD4200



TMULDHX04 LEVEL 3



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32 - LANDING GEAR

32-00-00 MAIN LANDING GEAR SERVICING

CONTENTS:Spare Seal Activating ValveTorque Link Damper

TMULDTT05 LEVEL 3



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MAIN LANDING GEAR SERVICING

SPARE SEAL ACTIVATING VALVE

DESCRIPTIONEach main landing gear fitting has a spare sealactivating valve. The activating valve is on the barrelof the main fitting, adjacent to the gland housingassembly. This valve can isolate the bottom gland sealsif a leak occurs from that position.

OPERATIONUnder normal conditions the valve stem of the spareactivating valve is screwed out, with the ball awayfrom its seat. Fluid pressure in the shock absorberis felt equally on both sides of the upper seal in thelower bearing sub-assembly, but only one side of thelower seal. Therefore, the lower seal is subjected topressure differentials.If a leak occurs at the lower bearing housing,indicated by the presence of hydraulic fluid on thesliding tube, the fault may be expected to be from thelower seal.The cap screw, an indicator, must be removed and thevalve stem screwed on to seat the ball. This actionisolates the lower seal from hydraulic pressure, whicheffectively stops the leak, and transfers the pressuredifferential to the upper seal.

TMULDTT05-T01 LEVEL 3



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MAIN LANDING GEAR SERVICING - SPARE SEAL ACTIVATING VALVETMULDTT05-P01 LEVEL 3



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MAIN LANDING GEAR SERVICING

TORQUE LINK DAMPER

DESCRIPTIONThe torque link damper is a spring centered, two wayhydraulic unit, which has its own pressurized hydraulicreservoir. Its function is to decrease the landingvibrations through the torque links.The hydraulic fluid contents of the damper are shownby the extension of the reservoir when it ispressurized. When the contents are correct, the "FULL"and "REFILL" level indications are in view.

REPLENISHMENTThe torque link damper must be fitted in accordancewith AMM 12-12-00, but we will consider the generaloutline of the task:

- First remove the cap assembly from the checkvalve, and bleed screw from the bleed plug,then attach a hydraulic charging rig, using aconnector, to the check valve.

- Next fit a plastic tube, which is SKYDROLcompatible, to the bleed plug, this is tocollect expelled fluid, so place the free endof the plastic tube into a suitable container.

- Using the hydraulic rig, apply a pressure of2.42 to 2.75 bars (35.1 to 39.9 psi) and openthe bleed plug until an air free flow of fluidis obtained.

- Increase the pressure to between 2.75 and 3.45bars (39.9 and 50 psi) and close the bleedplug, the reservoir can should rise slightlyabove the "FULL" line (approximately 2.5 mm/0.1inch).

- Remove the hydraulic rig and bleed tube, thencheck for leakage over the next 3 minutes atthe same time ensuring the reservoir canremains above the "FULL" line.

- Finally open the bleed plug slowly untilreservoir can is level with the "FULL"line, then close and lock the bleed and capassemblies.

TMULDTT05-T02 LEVEL 3



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TMULDTT05-P02 LEVEL 3

MAIN LANDING GEAR SERVICING - TORQUE LINK DAMPER



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TMULDTT05 LEVEL 3



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32 - LANDING GEAR

32-00-00 MAIN LANDING GEAR SHOCK ABSORBERSERVICING

CONTENTS:GeneralServicing ProceduresNitrogen Filling of the MLG Two-Stage Shock AbsorberPressure/Extension Graph - Values of the Film

TMULDGA06 LEVEL 3



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MAIN LANDING GEAR SHOCK ABSORBER SERVICING

GENERAL

PA is the pressure measured at the top charging valve(valve A).PB is the pressure measured at the bottom chargingvalve (valve B).H is the height of the shock aborber measured as shownbellow.

TMULDGA06-T01 LEVEL 3



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GENERAL - TOP CHARGING VALVE - BOTTOM CHARGING VALVE - H MEASUREMENTTMULDGA06-P01 LEVEL 3



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SERVICING PROCEDURES

Inspection of the MLG Shock Absorber Before Flight

Check Charge and Nitrogen Filling of the MLG Two-StageShock Absorber




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SERVICING PROCEDURESTMULDGA06-P02 LEVEL 3



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Nitrogen Filling of the MLG Two-Stage Shock Absorber(metric units)




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SERVICING PROCEDURES - NITROGEN FILLING OF THE MLG TWO-STAGE SHOCK ABSORBER (metric units)TMULDGA06-P03 LEVEL 3



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Nitrogen Filling of the MLG Two-Stage Shock Absorber(US units)




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TMULDGA06-P04 LEVEL 3

SERVICING PROCEDURES - NITROGEN FILLING OF THE MLG TWO-STAGE SHOCK ABSORBER (US units)



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NITROGEN FILLING OF THE MLG TWO-STAGE SHOCK ABSORBER

This film includes several procedures or parts ofprocedures of the shock absorber servicing:

- Check Charge Pressure of the Main Landing GearShock Absorber,

- Visual Inspection of the Main Landing GearTwo-Stage Shock Absorber for Leakage ofHydraulic Fluid,

- Nitrogen Filling of the Main Landing GearTwo-Stage Shock Absorber (Aircraft on theGround).

The values of some parameters such as temperature,pressure, etc, have to be recorded to perform thisprocedure. Depending on the value obtained, some partsmust or must not be done, referring to the AircraftMaintenance Manual.Of course, when you will effectively do it, you willhave to adapt your actions to the values you willobtain. In no case, can the values used in this filmbe used as a reference.WARNING: PUT THE SAFETY DEVICES AND THE WARNING NOTICES

IN POSITION BEFORE YOU START A TASK ON ORNEAR:- THE FLIGHT CONTROLS,- THE FLIGHT CONTROL SURFACES,- THE LANDING GEAR AND THE RELATED DOORS,- ANY COMPONENTS THAT MOVE.MAKE SURE THAT THE GROUND SAFETY-LOCKS AREIN POSITION ON THE LANDING GEAR.

Note that it is recommended that you wait a minimumof ten minutes after taxiing or towing before you carryout this procedure. This will allow to get a stabletemperature and a more accurate value of the shockabsorber extension and pressures.During this procedure, actions will be made on the topcharging valve (also called valve A), and on the bottomcharging valve (also called valve B).A placard located underneath the top charging valvegives you a summary of the information necessary toperform this procedure.It consists of:

- a gear schematic which shows you where you haveto measure the height H,

- a summarized actions list which presents themain points necessary to perform the dedicatedprocedures,

- DIAGRAM 1 which allows you to find a targetvalue H depending on the measured temperatureand the pressure on the top charging valve,

- DIAGRAM 2 which gives the same information,but for a different step of the procedure,

- DIAGRAM 3 enables you to find the positionof a point determined by the temperatureand the pressure values in relation to agraph line.




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NITROGEN FILLING OF THE MLG TWO-STAGE SHOCK ABSORBER - SHOCK ABSORBER SCHEMATICTMULDGA06-P05 LEVEL 3



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NITROGEN FILLING OF THE MLG TWO-STAGE SHOCK ABSORBER(cont’d)

PREPARATIONIn the cockpit,make sure that the landing gear control lever is inthe DOWN position and put a warning notice in positionto tell people not to operate the landing gear.On the outside,

- make sure that the wheel chocks are in positionon the main landing gear, but do not put achock on the nose wheel,

- put a warning notice in position to tell personsnot to operate the landing gear doors,

- put the access platform in position below theapplicable shock absorber.

Before filling with nitrogen, examine the gland housingof the shock absorber for leakage of hydraulic fluid.In case of leakage, refer to your AMM to troubleshoot.

PROCEDUREMeasure and record dimension H, H = 89 mm (3.50 in).Measure and record the temperature of the MLG adjacentto the top charging valve, T = 10ºC (50ºF).Put the standard charging equipment into position.On the top charging valve:

- remove the blanking cap,- on the charging equipment, make sure that thecontrol valves are closed,

- and connect the filling hose.Do the same on the bottom charging valve.CAUTION: MAKE SURE THAT YOU USE A GAGE WITH THE

SPECIFIED PRESSURE RANGE.

On the top charging valve:- slowly open it,- read and record the pressure shown on thepressure gage, PA = 79 bar (1150 psi),

- and then close it.Do the same on the bottom charging valve, PB = 75 bar(1090 psi).Using DIAGRAM 1, find the dimension HA for the pressureat the top charging valve and the measured temperature,HA = 141mm (5.6 in) (1).As the condition H = HA ± 15mm (0.6 in) is not fulfilledwe have to do the Nitrogen Filling of the MLG Two-StageShock Absorber.The pressure at the bottom charging valve must bebetween 13.8 and 20.7 bar (200 and 300 psi) above thepressure at the top charging valve,

PA + 13.8 bar < PB < PA + 20.7 bar.This is to ensure that the floating piston is at thetop of the bottom chamber (key point in case ofrestart).To perform this condition, we are going to pressurizethe bottom chamber.WARNING: DO NOT PUT COMPRESSED GAS IN CONTACT WITH

YOUR SKIN. THE GAS CAN GO THROUGH THE SKINAND CAUSE BUBBLES IN THE BLOOD. THIS COULDCAUSE DEATH.MAKE SURE THAT THE AREA AROUND THE AIRCRAFTIS CLEAR OF PERSONS AND EQUIPMENT. WHEN YOUPRESSURIZE OR DEPRESSURIZE THE SHOCKABSORBER, WITH THE AIRCRAFT WEIGHT ON THEGROUND, THE AIRCRAFT WILL MOVE.




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CAUTION: ALWAYS ADD NITROGEN SLOWLY WHEN YOUPRESSURIZE THE SHOCK ABSORBER. IF YOU ADDNITROGEN TOO QUICKLY, THE TEMPERATURE WILLINCREASE AND HAVE AN EFFECT ON THE SHOCKABSORBER PRESSURE.

FILLINGOn the bottom charging valve:

- the nitrogen supply being open, open the bottomcharging valve,

- open the control supply valve slowly to addnitrogen to the bottom chamber, PB = 98 bar(1420 psi),

- close the bottom charging valve.Wait ten minutes and make sure that the pressurecondition is fulfilled. The bottom chamber pressureis still the same, PB = 98 bar (1420 psi).Check the pressure of the top chamber too:

- slowly open the top charging valve,- read and record the pressure shown on thepressure gage, PA = 92 bar (1330 psi),

- and then close it.As the pressure condition is NOT fulfilled(PA + 13.8 bar < PB < PA + 20.7 bar), we have to increasethe pressure in the bottom chamber by adding nitrogen.On the bottom charging valve:

- the bottom charging valve being open, open thecontrol supply valve slowly to add nitrogen tothe bottom chamber, PB = 112 bar (1620 psi),

- and close the bottom charging valve.

Wait ten minutes and make sure that the pressurecondition between the two chambers is fulfilled,PA = 92 bar (1330 psi), PB = 112 bar (1620 psi). Thepressure condition is fulfilled.The nitrogen pressure being released, read and writedown the temperature again, T = 11ºC (52ºF), as wellas the dimension H, H = 123 mm (4.8 in).Make sure that the difference in pressure at the topcharging valve and the bottom charging valve is morethan 10.7 bar (155 psi),

PB > PA + 10.7 bar,this condition being enough at this point.Using DIAGRAM 2, find the dimension HA for the pressureand the temperature at the top charging valve,HA = 140 mm (5.5 in) (2).Dimension H must be the same as HA, ± 1mm (0.6 in).Depending on whether H, is higher or lower than thevalue of HA found on DIAGRAM 2, we have respectivelyto remove or add nitrogen from the top chamber.As H is lower than the value of H found on DIAGRAM 2we have to add nitrogen to the top chamber.




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To do that:- open the top charging valve,- the nitrogen supply being open, slowly openthe control valve to add nitrogen; as soon asthe shock absorber moves, close the controlvalve,

- after 5 minutes, measure the temperature,T = 11ºC (52ºF), and the pressure at the topcharging valve, PA = 92 bar (1330 psi),

- using DIAGRAM 2, find the dimension HA requiredfor these conditions, HA = 140 mm (5.5 in),

- slowly open the control valve to add nitrogento obtain the same dimension H as we foundbefore, H = HA ± 1mm (0.6 in).

After 5 minutes, open the top and the bottom chargingvalves.Read and write down:

- pressures, PA = 92 bar (1330 psi),PB = 112 bar (1620 psi),

- the temperature, T = 11ºC (52ºF),- the dimension H, H = 139 mm (5.5 in).

Using the pressure and the temperature find the correctdimension H in DIAGRAM 2 and make sure that this valueis equal to the previous measured value, ± 1mm (0.6in).Make sure that the difference in pressure at the topcharging valve and the bottom charging valve is stillmore than 10.7 bar (155 psi), PB > PA + 10.7 bar.Close the top and the bottom charging valves.

Now, depending on if the pressure and temperature ofthe top charging valve is either, on or below, or abovethe graph line on DIAGRAM 3 (3), there are twopossibilities.In our case, as PA is above the graph line, we haveto carry out the following steps:

- using DIAGRAM 1, find the dimension HA for thepressure at the top charging valve and themeasured temperature, HA = 119 mm (4.7 in) (4),

- open the bottom charging valve,- slowly open the control valve to removenitrogen and immediately the dimension H startsto change, close the control valve,

- after 5 minutes, open the top charging valve,and read and record the pressure, PA = 86 bar(1250 psi), and the temperature, T = 11ºC(52ºF),

- using DIAGRAM 1, find the dimension H that youneed for the above conditions, HA = 125 mm (4.9in) (5),

- slowly open the control valve to removenitrogen from the bottom charging valve untilthe dimension H is the same as the dimensionH found in DIAGRAM 1, ± 1 mm (0.6 in),

- close the bottom charging valve.After 5 minutes, check the pressures:

- open the top charging valve, read and writedown the pressure, PA = 86 bar (1250 psi), andthen close it,

- open the bottom charging valve, read andwrite down the pressure, PB = 85 bar (1230psi), and then close it.




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Make sure that the pressure at the top and bottomcharging valves are the same, ± 1.5 bar (22 psi). Ifnot, you have to do the procedure again starting fromthe step where the floating piston must be moved tothe top of the bottom chamber.

CLOSE-UPRelease the nitrogen pressure.On the bottom charging valve:

- torque the valve to the preset value,- remove the charging equipment,- use SPECIAL MATERIALS to do a leak check ofthe valve,

- install the blanking cap.Remove the thermometer.On the top charging valve:

- do the same as on the bottom charging valve.Remove the access platform.Examine the gland seal of the shock absorber for signsof oil leaks.Remove the ground support and maintenance equipment,the special and standard tools and all other items.Remove the warning equipment and notices.Make sure that the work area is clean and clear oftools and other items.




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PRESSURE/EXTENSION GRAPH - VALUES OF THE FILM

Find below the points noticed during the film in theirchronological order.

DIAGRAM 1(1) PA = 79 bar (1150 psi), T = 10ºC (50ºF)

HA = 141 mm (5.6 in)(4) PA = 92 bar (1330 psi), T = 11ºC (52ºF)

HA = 119 mm (4.7 in)(5) PA = 86 bar (1250 psi), T = 11ºC (52ºF)

HA = 125 mm (4.9 in)

DIAGRAM 2(2) PA = 92 bar (1330 psi), T = 11ºC (52ºF)

HA = 140 mm (5.5 in)

DIAGRAM 3(3) PA = 92 bar (1330 psi)




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PRESSURE/EXTENSION GRAGH - VALUES OF THE FILMTMULDGA06-P07 LEVEL 3



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TMULDGA06 LEVEL 3



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32 - LANDING GEAR

32-43-00 LOW PRESSURE CIRCUIT FILLING ANDBLEEDING

CONTENTS:PrecautionsProcedure

TMULDGM01 LEVEL 3



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LOW PRESSURE CIRCUIT FILLING AND BLEEDING

PRECAUTIONS

Aircraft configuration: All safety precautions arefulfilled (Refer to AMM).

PROCEDURE

- Yellow hydraulic circuit and brake accumulatorare depressurized.

- Use de-aerated hydraulic fluid.- Disconnect hydraulic hoses from the mastercylinders and connect master cylinders tohydraulic fluid recovery containers with vinyltubing.

- Open bleeder J, bleeder K remains closed.- Fill the system with the hand pump until thefluid flows from the vinyl pipe and there areno air bubbles. Make sure that the supplypressure is no more than 15 bars (217.6 psi).

- Close the bleeder J, open the bleeder K andcarry out the same procedure.

- Connect hydraulic hoses to the base of the leftand the right master cylinders.

- Connect the vinyl tubing to the reservoirbleeder (do not unscrew the bleeder).

- Open the bleeders J and K of the dual valveand continue to fill until the fluid whichflows from the reservoir bleeder is free ofair bubbles.

- Check that the reservoir is full (indicatorfully extended to the stop position).

- Open the reservoir bleeder to adjust the levelof the fluid in the reservoir to normal (thepiston is level with the green band).

- Close the supply valves of the dual valve.- Close the bleeders on the dual valve andreservoir.

- With the yellow hydraulic systempressurized and the pressure of the greenhydraulic system depressurized push in thepedals and check that the pressure valueshown on the brake yellow pressure tripleindicator is correct.

TMULDGM01-T01 LEVEL 3



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LOW PRESSURE CIRCUIT FILLING AND BLEEDINGTMULDGM01-P01 LEVEL 3



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TMULDGM01 LEVEL 3



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32 - LANDING GEAR

32-41-00 WHEEL AND BRAKEREMOVAL/INSTALLATION

CONTENTS:MLG Wheel and Brake Removal/InstallationNLG Wheel Removal/Installation

TMULDVV0B LEVEL 2



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WHEEL AND BRAKE REMOVAL/INSTALLATION

MLG WHEEL AND BRAKE REMOVAL/INSTALLATION

GENERALThis procedure includes removal/installationoperations of the following components/systems:

- brake fan (optional),- Tire Pressure Indicating System (optional),- ABS wheel and brake.

Even if your aircraft is not equipped with one or bothoptional systems or this type of wheel and brake, theprocedure remains the same.

PREPARATIONOutside,

- make sure that the landing gear safety devicesare in position,

- as well as the wheel chocks.In the cockpit,

- open, safety and tag the TPIS and the brakefans circuit breakers,

- put warning notices on the free fall controlhandle and on the landing gear control lever,

- set the parking brake to OFF,- make sure that the pressure is off and the brakefan pushbutton is set to off.

Outside again,- put the jack in position,- make sure that the dome correctly engages,- lift the landing gear.

WHEEL REMOVAL- Fully deflate the tire if it must be changed.- Remove the guard assembly attached by means of6 screws.

- Remove the lock wire.- Insert a tool to lock the impeller and unscrewthe nut.

- Remove the impeller.- Remove the shroud fixed by 2 screws.- Disconnect the TPIS sensor connector from therotating transformer. Note that the TPIS sensormust be removed from the wheel if it is changed.

- Remove the "V" clamp and the shroud support.- Discard the cotterpins, loosen and remove the2 locking bolts.

- Loosen the wheel nut using the torque adaptorand remove it.

- Install the propely greased protection tool.- Using a specific tool, remove the wheel.

BRAKE REMOVAL- Disconnect the self-sealing couplings.- Disconnect the brake temperature sensor.- Using an adaptor, loosen and remove the threenuts and washers.

- The protective tool being installed on theaxle, remove the wheel.

TMULDVV0B-T01 LEVEL 2



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MLG WHEEL AND BRAKE REMOVAL/INSTALLATION (CONTINUED)

BRAKE INSTALLATION- Remove the protective tool, clean and greasethe axle.

- The protective tool being fitted, install thebrake unit.

- Make sure that the studs engage correctly onthe axle.

- Install the 3 washers and nuts.- Adjust the torquemeter value and torque the 3nuts.

- Connect the brake temperature sensor.- Reconnect the self-sealing couplings.- Remove the protection devices.

WHEEL INSTALLATION- Make sure that the driving keys on the brakerotor are correctly aligned.

- The axle protective tool being fitted, installthe wheel with the tool.

- Remove the protection device.- Install the axle nut.- Adjust the torque meter to the pre-torque valueand apply it to the nut while turning the wheel.

- Prevent the rotation of the wheel and loosenthe nut.

- Adjust the torque meter to the torque value.- Torque the axle nut.- Tighten it until the holes in the nut arealigned with the holes in the axle.

- Install the locking nuts with the head of thescrews facing the axle.

- Fit the washers an the nuts.- Tighten the nut.- Safety the locking nuts with splitpins.- Install the shroud support centered by acentering pin and tighten the "V" clamp.

- Reconnect the TPIS sensor plug.- Install the shroud with the 2 srews.- Align the splined driving shaft with theimpeller.

- Install the impeller, prevent its rotation andtighten the nut.

- Safety the nut with lockwire.- Install the guard on the tachometer driveshaft and fit it with the 4 screws.




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MLG WHEEL AND BRAKE REMOVAL/INSTALLATION (CONTINUED)

CLOSE-UP- Make sure that the area is clean. Lower thelanding gear, the tire pressure beingpreviously checked and adjusted.

- Carefully remove the jack from the landing geardome.

In the cockpit,- remove the tags and close the circuit breakers,- select the ECAM HYDraulic page,- pressurize the green hydraulic system,- press the braking pedals.

Outside,- check the forward coupling for any leakage.

In the cockpit,- apply the parking brake and check the pressureon the triple gage indicator.

Outside,- check the rear coupling for any leakage,

In the cockpit,- depressurize the hydraulic systems,- select the ECAM WHEEL page,- check the brake temperature and tire pressurefor correct indication,

- select the brake fans ON.Outside,

- check the brake fans for correct operation.In the cockpit,

- select the brake fans off and remove thewarning notices.




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NLG WHEEL AND BRAKE REMOVAL/INSTALLATION

PREPARATIONOutside,

- make sure that the safety locks and wheel chocksare in position on the landing gear.

In the cockpit,- open, safety and tag the TPIS circuit breaker,- put warning notices on the free fall and landinggear control handles,

- select the parking brake OFF.Outside again,

- put the jack in position,- make sure that the dome correctly engages,- lift the landing gear- fully deflate the tire.

WHEEL REMOVAL- Cut and remove the lock wire.- Remove the 3 srews and washers and remove thehubcap.

- Remove the grommet and disconnect the TPISsensor plug from the rotating transducer. Notethat the sensor has to be removed from thewheel and refitted on the new wheel.

- Remove and discard the cotterpins.- Remove the 2 locking nuts.- Remove the axle nut with the torque adaptor.- Install the properly greased protection tool.- Remove the wheel.- Attach a correctly filled-in label on it.

WHEEL INSTALLATION- Install the protection tool if removed.- Correctly grease the axle.- Install the wheel.- Remove the protection tool.- Install the nut.- Adjust the torque meter to the pre-torque valueand apply it to the nut while turning the wheel.

- Prevent the wheel from rotating and loosen thenut.

- Adjust the torque meter to the correct value.- Torque the nut.- Tighten until the locking bolt holes arealigned.

- Install the locking bolt with the head of thescrew facing the axle.

- Fit the washers and nuts.- Safety the locking nuts with split pins.- Connect the TPIS sensor to the rotatingtransducer.

- Re-install the grommet.- Put the hubcap in position.- Install the 3 washers and screws.- Safety the 3 srews with lockwire.




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NLG WHEEL AND BRAKE REMOVAL/INSTALLATION (CONTINUED)

CLOSE-UPOutside,

- make sure that the working area is clean,- lower the gear, the tire pressure beingpreviously checked and ajusted,

- carefully remove the jack from the dome,- put the chocks back in position.

In the cockpit,- remove the tag and close the TPIS circuitbreaker,

- remove the safety warnings,- select the WHEEL ECAM page,- check the pressure for correct indication.




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32 - LANDING GEAR

32-00-00 CFDS SPECIFIC PAGE PRESENTATION

CONTENTS:LGCIU 1BSCU ATPIS

TMULDGRZZ LEVEL 3



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CFDS SPECIFIC PAGE PRESENTATION

GENERAL

LGCIU 1 and LGCIU 2 have the same functions, thus onlyLGCIU 1 is shown on the MCDU.BSCU A and BSCU B have the same functions, thus onlyBSCU A is shown on the MCDU.The Tire Pressure Indicating System is provided as anoption.On the SYSTEM REPORT/TEST L/G menu page, the "TPIS"line is always displayed, even if this system is notfitted on the aircraft.

LGCIU 1

LANDING GEAR SIMULATIONThe landing gear simulation function is an aid for themaintenance technicians during trouble shooting andthe maintenance tasks.With this function it is not necessary to:

- lift the aircraft on jacks (to operate theproximity sensors on the gear),

- operate the landing gear.During the simulation of a landing gear configurationthe:

- BITE causes the LGCIU to supply output datathat agrees with the simulated configuration,

- ARINC 429 and discrete signals go to theapplicable interface systems.

Two examples have been chosen:NOSE LANDING GEAR

- Aircraft position: nose landing gear iscompressed and downlocked.

- Via the MCDU: nose landing gear extended oruplocked can be simulated.

LH + RH MAIN LANDING GEAR- Aircraft position: Main gear is compressed and

downlocked.- Via the MCDU: Main gear extended or uplocked

can be simulated.

NOTE: Using the RETURN line key allows the landinggear system to be reconfigured to the normalposition.

TMULDGRZZ-T01 LEVEL 3



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CFDS SPECIFIC PAGE PRESENTATION - LGCIU 1TMULDGRZZ-P01 LEVEL 3



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BSCU A

NOTE: STEERING DATA function access is only availablewith BSCU standard 8.

PIN-PROG SELECTIONAs braking and anti-skid computation depend on tirediameter, if, for any reason you have to use acompatible BSCU from another aircraft, some actionsmust be done (refer to AMM).This function is used after removal/installation ofthe BSCU. Its purpose is to adapt the BSCUpin-programming to the aircraft pin-programming.At the end of menu mode, the system must be set to"OFF" then to "ON" to be correctly reset using theA/SKID & N/W STRG switch.Moreover, the pin-programming modification must alsobe performed on the second BSCU system.

NOTES: The pin-programming reference can be checkedusing system 1 and 2 LRU IDENTIFICATION pages.PIN-PROG SELECTION menu pages can be slightlydifferent depending on if BSCU standard 7 orBSCU standard 8 is installed. Whatever yourconfiguration is, the principle remians thesame.

STEERING DATASTEERING DATA function displays in real time and clearlanguage some parameters of the nose wheel steeringsystem. This function allows any possiblemalfunctioning of this system to be identified in caseof a non axial roll-out.

Displayed data- SELV ORDER = selector valve status (OPEN or

CLOSED).- SSV CURRENT = servovalve current comprised

between -10mA and +10mA.- STEER ORDER = commanded steering angle.- CAPT ANGLE = CAPT steering handwheel angle.- FO ANGLE = F/O steering handwheel angle.- PEDAL ANGLE = ELAC angle.- NWS ANGLE3GC= RVDT COM angle.- SSV SPOOL = LVDT spool position comprised

between -0.6 mm and +0.6 mm.The REFRESH key is used to refresh the values of thenose wheel steering parameters, as required.




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TMULDGRZZ-P02 LEVEL 3

CFDS SPECIFIC PAGE PRESENTATION - BSCU A



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TPIS

REF PRESSUREThis item displays the values of the landing gear wheelreference pressures wired at the rear of the computerby pin programming.

GROUND FAULTSThis mode gives all class 1, 2 and 3 faults that haveoccured on the ground with a memory capacity of 3faults maximum during the last 64 flights.




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CFDS SPECIFIC PAGE PRESENTATION - TPISTMULDGRZZ-P03 LEVEL 3



UFD4200



TMULDGRZZ LEVEL 3



UFD4200


32-LANDING GEAR

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Transcript of 32-LANDING GEAR