INDICATING AND WARNING - DESCRIPTION AND OPERATION

** ON A/C NOT FOR ALL

1. General
The indicating and warning system gives position and warning data for the landing gear (L/G) and L/G doors. The system uses the data from proximity sensors in the Normal Extension and Retraction System (Ref. AMM D/O 32-31-00-00). The proximity sensors give the positions of the L/G components to the Landing Gear Control and Interface Units (LGCIU) (Ref. AMM D/O 32-31-00-00). The LGCIU's, 5GA1 and 5GA2, process the L/G position data and indications are given to the flight crew on:

the Electronic Centralized Aircraft Monitoring (ECAM) Display Units (DU)
the L/G position-indicator lights.

The Central Warning system uses aural and visual equipment to tell the flight crew that a fault has occurred in the L/G system.

** ON A/C NOT FOR ALL

2. Component Location

Cockpit Component Location ** ON A/C NOT FOR ALL

FIN	FUNCTIONAL DESIGNATION	PANEL	ZONE	ATA REF
** ON A/C ALL
5GA1	LGCIU-1	93VU	121	32-31-71
5GA2	LGCIU-2	94VU	122	32-31-71
6GA	LEVER-L/G NORM CTL	400VU	212	32-31-11

** ON A/C NOT FOR ALL

3. System Description

Landing Gear System - Block Diagram

The system has three functions:

to give L/G position data to interfaced systems
to give L/G position indication
to give warnings and cautions that are related to L/G system failures.

A. Position Data

Proximity sensors (installed on the L/G and L/G doors) give position data to two LGCIUs. There are two sets of sensors (System 1 and System 2), one set for each LGCIU. The LGCIU's process the data and give two types of output. They are:

discrete logic signals
ARINC 429 data.

Discrete logic signals are given to the applicable systems when:

the NLG shock absorber is compressed
the NLG shock absorber is not compressed
the NLG or the L/H MLG or the R/H MLG are downlocked
the L/H or the R/H MLGs are in a ground condition (the applicable gear(s) is(are) locked down)
the L/H or the R/H MLGs are in a flight condition (not the ground condition).

ARINC 429 data is given to the applicable systems all of the time. These outputs give the L/G and L/G doors position data together with other L/G system status data.

B. Indication

The position of the L/G is shown to the crew on:

the WHEEL page of the ECAM system
the L/G downlock indicator lights.

The WHEEL page shows the position of each L/G and its door. The L/G and L/G door indications are given with data from LGCIU1 (System 1) and LGCIU2 (System 2).

The WHEEL page shows automatically when:

the first engine starts until the first engine gets to take-off power
the L/G is selected DOWN or at 1600 ft radio altitude (whichever is the first to occur) until the second engine shutdown.

If it is necessary for the crew to see the WHEEL page at other times, they can make a selection on the ECAM control panel.

The L/G downlock indicator-lights each show the position of a L/G (but not the L/G doors). Each light is in two parts and can show:

the color red and the legend UNLK in the top half (L/G not in selected position)
the color green in the bottom half (L/G downlocked)
no lights (L/G uplocked).

The green lights for the NLG and each MLG have different proximity sensors, logic circuits and power supplies. This makes sure that the NLG and MLG green lights operate independently.

C. Cautions and Warnings

Cautions and warnings are given with:

the WHEEL page of the ECAM system
the CWS
the landing gear control lever (Ref. AMM D/O 32-31-00-00).

The WHEEL page shows automatically if these warning messages show on the ECAM upper DU:

LGCIU 1(2) FAULT
L/G DOORS NOT CLOSED
L/G GEAR NOT UPLOCKED
L/G GEAR NOT DOWNLOCKED
L/G GEAR UPLOCK FAULT
L/G SYS DISAGREE.

If necessary, a procedure to correct the effects of the failure is given with the warning message. When some of these failure messages show, the master warning or caution lights come on and a continuous or single chime sounds.

D. L/G Control Lever

The 'down arrow' light in the L/G control lever comes on if the conditions that follow occur:

the L/G is not locked down
the aircraft is in a landing configuration.

** ON A/C NOT FOR ALL

4. Power Supply

Landing Gear Indicating and Warning - Schematic

** ON A/C NOT FOR ALL

5. Interface

LGCIU - Users of ARINC 429 Output Data

A. LGCIU - ARINC 429 Output Data

The LGCIUs send data along the ARINC 429 data busses to the CFDS and on to the MCDUs.

The parameter lists that follow give the data that each LGCIU can send

on its three ARINC 429 data busses. These lists give this data:

- EQPT, the equipment number for the computer that sends the parameter

- SYS, the system number of the computer which sends the parameter

- LABEL, the label of the parameter (ARINC 429 octal value)

- SDI, the Source/Destination Identifier for each system. (01 identifies

that the output data is from the LGCIU in system No 1. 10 identifies

that the output data is from the LGCIU in system No 2)

- PARAMETER DEFINITION, the parameter name

- RANGE/ACCURACY, for the LGCIUs, this column to show the condition

of the ARINC 429 Discrete Data Words. Only the bit condition for a

parameter that is correct (bit status 1), is shown. In all cases the

the bit condition is low (bit status 0) when the parameter is incorrect

- UNIT, when applicable, this column gives the units used in the RANGE

column (e.g. knots, degrees)

- SIG BIT, this column shows if a sign bit is available and in which bit

position of the data word it is found

- DATA BITS, this column gives, the quantity of data bits in use for each

label and the number of each data bit. (For BCD coded data words this

symbol "(1)" shows the number of significant data digits)

- UPD/MSEC, this tells you how frequently a LGCIU sends data

- CODE:

BNR = binary data word

BCD = binary coded decimal data word

ISO = data word coded in ISO 5 Code

DIS = discrete data word

HEX = hexadecimal coded

OCT = octal coded

HYB = mixed code, e.g. bit 11 to 16 DIS, bit 17 to 28 BNR

- ALPHA CODE, this column shows the code for a parameter (if

available). When you enter this code through a MCDU the display shows

the current parameter(s) for each of the LGCIUs

- SOURCE ORIGIN, the initial source of the parameter

- BUS N0. the identification numbers of the data busses connected to the

source computer

- ATA REF, the ATA Chapter in which you can find the computer that is

the source of the parameter

- CONV, when applicable this gives the parameter LABEL at the output of

the source computer (for the case of a change in a parameter LABEL as

it goes through a computer).

LGCIU 1/2 PARAMETER LIST EQPT 6D

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| PARAMETER LIST PARAMETER CHARACTERISTICS (NUMERIC) |

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! 1 020 01 !LGCIU ! ! ! ! 19 !100 !DIS ! !LGCIU !

! 2 020 10 !DISCRETE ! ! ! ! ! ! ! !1/2 !

! !WORD No1 ! ! ! ! ! ! ! ! !

! !----------!------------!----!----!----!----!----!-----!1,2,3 !

! !LH GEAR !BIT STATUS 1! ! !No11! ! ! ! !

! !NOT LKD UP! ! ! ! ! ! ! !32-31- !

! !AND NOT ! ! ! ! ! ! ! !00 !

! !SEL DN ! ! ! ! ! ! ! ! !

! !----------!------------!----!----!----!----!----!-----! !

! !RH GEAR !BIT STATUS 1! ! !No12! ! ! ! !

! !NOT LKD UP! ! ! ! ! ! ! ! !

! !AND NOT ! ! ! ! ! ! ! ! !

! !SEL DN ! ! ! ! ! ! ! ! !

! !----------!------------!----!----!----!----!----!-----! !

! !NOSE GEAR !BIT STATUS 1! ! !No13! ! ! ! !

! !NOT LKD UP! ! ! ! ! ! ! ! !

! !AND NOT ! ! ! ! ! ! ! ! !

! !SEL DN ! ! ! ! ! ! ! ! !

! !----------!------------!----!----!----!----!----!-----! !

! !LH GEAR !BIT STATUS 1! ! !No14! ! ! ! !

! !NOT LKD DN! ! ! ! ! ! ! ! !

! !AND SEL DN! ! ! ! ! ! ! ! !

! !----------!------------!----!----!----!----!----!-----! !

! !RH GEAR !BIT STATUS 1! ! !No15! ! ! ! !

! !NOT LKD DN! ! ! ! ! ! ! ! !

! !AND SEL DN! ! ! ! ! ! ! ! !

! !----------!------------!----!----!----!----!----!-----! !

! !NOSE GEAR !BIT STATUS 1! ! !No16! ! ! ! !

! !NOT LKD DN! ! ! ! ! ! ! ! !

! !AND SEL DN! ! ! ! ! ! ! ! !

! !----------!------------!----!----!----!----!----!-----! !

! !LH DOOR !BIT STATUS 1! ! !No17! ! ! ! !

! !NOT UPLKD ! ! ! ! ! ! ! ! !

! !----------!------------!----!----!----!----!----!-----! !

! !RH DOOR !BIT STATUS 1! ! !No18! ! ! ! !

! !NOT UPLKD ! ! ! ! ! ! ! ! !

! !----------!------------!----!----!----!----!----!-----! !

! !NOSE GEAR !BIT STATUS 1! ! !No19! ! ! ! !

! !DOORS NOT ! ! ! ! ! ! ! ! !

! !UPLKD ! ! ! ! ! ! ! ! !

! !----------!------------!----!----!----!----!----!-----! !

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| PARAMETER LIST PARAMETER CHARACTERISTICS (NUMERIC) |

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! !LH GEAR !BIT STATUS 1! ! !No20! ! ! ! !

! !UPLOCK IN ! ! ! ! ! ! ! ! !

! !LKD POS ! ! ! ! ! ! ! ! !

! !WITH LH ! ! ! ! ! ! ! ! !

! !GEAR DNLKD! ! ! ! ! ! ! ! !

! !----------!------------!----!----!----!----!----!-----! !

! !RH GEAR !BIT STATUS 1! ! !No21! ! ! ! !

! !UPLOCK IN ! ! ! ! ! ! ! ! !

! !LKD POS ! ! ! ! ! ! ! ! !

! !WITH RH ! ! ! ! ! ! ! ! !

! !GEAR DNLKD! ! ! ! ! ! ! ! !

! !----------!------------!----!----!----!----!----!-----! !

! !NOSE GEAR !BIT STATUS 1! ! !No22! ! ! ! !

! !UPLOCK IN ! ! ! ! ! ! ! ! !

! !LKD POS ! ! ! ! ! ! ! ! !

! !WITH NOSE ! ! ! ! ! ! ! ! !

! !GEAR DNLKD! ! ! ! ! ! ! ! !

! !----------!------------!----!----!----!----!----!-----! !

! !LH GEAR !BIT STATUS 1! ! !No23! ! ! ! !

! !DNLKD ! ! ! ! ! ! ! ! !

! !----------!------------!----!----!----!----!----!-----! !

! !RH GEAR !BIT STATUS 1! ! !No24! ! ! ! !

! !DNLKD ! ! ! ! ! ! ! ! !

! !----------!------------!----!----!----!----!----!-----! !

! !NOSE GEAR !BIT STATUS 1! ! !No25! ! ! ! !

! !DNLKD ! ! ! ! ! ! ! ! !

! !----------!------------!----!----!----!----!----!-----! !

! !LH L/G !BIT STATUS 1! ! !No26! ! ! ! !

! !SHOCK- ! ! ! ! ! ! ! ! !

! !ABSORBER ! ! ! ! ! ! ! ! !

! !NOT ! ! ! ! ! ! ! ! !

! !EXTENDED ! ! ! ! ! ! ! ! !

! !----------!------------!----!----!----!----!----!-----! !

! !RH L/G !BIT STATUS 1! ! !No27! ! ! ! !

! !SHOCK- ! ! ! ! ! ! ! ! !

!ABSORBER ! ! ! ! ! ! ! ! !

! !NOT ! ! ! ! ! ! ! ! !

! !EXTENDED ! ! ! ! ! ! ! ! !

! !----------!------------!----!----!----!----!----!-----! !

! !NOSE L/G !BIT STATUS 1! ! !No28! ! ! ! !

! !SHOCK- ! ! ! ! ! ! ! ! !

! !ABSORBER ! ! ! ! ! ! ! ! !

! !NOT ! ! ! ! ! ! ! ! !

! !EXTENDED ! ! ! ! ! ! ! ! !

! !----------!------------!----!----!----!----!----!-----! !

! !L/G !BIT STATUS 1! ! !No29! ! ! ! !

! !SEL DN ! ! ! ! ! ! ! ! !

! !(LEVER ! ! ! ! ! ! ! ! !

! !POSITION) ! ! ! ! ! ! ! ! !

!--------------!----------!------------!----!----!----!----!----!-----!-------!

LGCIU 1/2 PARAMETER LIST EQPT 6D

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| PARAMETER LIST PARAMETER CHARACTERISTICS (NUMERIC) |

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! 1 021 01 !LGCIU ! ! ! ! 17 !100 !dis !LGDW !LGCIU !

! 2 021 10 !DISCRETE ! ! ! ! ! ! ! !1/2 !

! !WORD No2 ! ! ! ! ! ! ! ! !

! !----------!------------!----!----!----!----!----!-----!1,2,3 !

! !MAIN (LH &!BIT STATUS 1! ! !No11! ! ! ! !

! !RH) L/G ! ! ! ! ! ! ! !32-31- !

! !COMPRESSED! ! ! ! ! ! ! !00 !

! !----------!------------!----!----!----!----!----!-----! !

! !NOSE L/G !BIT STATUS 1! ! !No12! ! ! ! !

! !COMPRESSED! ! ! ! ! ! ! ! !

! !----------!------------!----!----!----!----!----!-----! !

! !LH L/G !BIT STATUS 1! ! !No13! ! ! ! !

! !COMPRESSED! ! ! ! ! ! ! ! !

! !----------!------------!----!----!----!----!----!-----! !

! !RH L/G !BIT STATUS 1! ! !No14! ! ! ! !

! !COMPRESSED! ! ! ! ! ! ! ! !

! !----------!------------!----!----!----!----!----!-----! !

! !MAIN L/G !BIT STATUS 1! ! !No15! ! ! ! !

! !(LH & RH) ! ! ! ! ! ! ! ! !

! !DNLKD ! ! ! ! ! ! ! ! !

! !----------!------------!----!----!----!----!----!-----! !

! !LH BOGIE !BIT STATUS 1! ! !No16! ! ! ! !

! !BEAM NOT ! ! ! ! ! ! ! ! !

! !ALIGNED ! ! ! ! ! ! ! ! !

! !----------!------------!----!----!----!----!----!-----! !

! !RH BOGIE !BIT STATUS 1! ! !No17! ! ! ! !

! !BEAM NOT ! ! ! ! ! ! ! ! !

! !ALIGNED ! ! ! ! ! ! ! ! !

! !----------!------------!----!----!----!----!----!-----! !

! !SPARE ! ! ! !No18! ! ! ! !

! !----------!------------!----!----!----!----!----!-----! !

! !SPARE ! ! ! !No19! ! ! ! !

! !----------!------------!----!----!----!----!----!-----! !

! !SYSTEM IN !BIT STATUS 1! ! !No20! ! ! ! !

! !CONTROL ! ! ! ! ! ! ! ! !

! !----------!------------!----!----!----!----!----!-----! !

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| PARAMETER LIST PARAMETER CHARACTERISTICS (NUMERIC) |

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! !L/G RETR !BIT STATUS 1! ! !No21! ! ! ! !

! !SOLENOID ! energized ! ! ! ! ! ! ! !

! !SPLY -VE ! ! ! ! ! ! ! ! !

! !----------!------------!----!----!----!----!----!-----! !

! !L/G RETR !BIT STATUS 1! ! !No22! ! ! ! !

! !SOLENOID ! energized ! ! ! ! ! ! ! !

! !SPLY 28V ! ! ! ! ! ! ! ! !

! !----------!------------!----!----!----!----!----!-----! !

! !L/G EXT !BIT STATUS 1! ! !No23! ! ! ! !

! !SOLENOID ! energized ! ! ! ! ! ! ! !

! !SPLY -VE ! ! ! ! ! ! ! ! !

! !----------!------------!----!----!----!----!----!-----! !

! !L/G EXT !BIT STATUS 1! ! !No24! ! ! ! !

! !SOLENOID ! energized ! ! ! ! ! ! ! !

! !SPLY 28V ! ! ! ! ! ! ! ! !

! !----------!------------!----!----!----!----!----!-----! !

! !DOORS OPEN!BIT STATUS 1! ! !No25! ! ! ! !

! !SOLENOID ! energized ! ! ! ! ! ! ! !

! !SPLY -VE ! ! ! ! ! ! ! ! !

! !----------!------------!----!----!----!----!----!-----! !

! !DOORS OPEN!BIT STATUS 1! ! !No26! ! ! ! !

! !SOLENOID ! energized ! ! ! ! ! ! ! !

! !SPLY 28V ! ! ! ! ! ! ! ! !

! !----------!------------!----!----!----!----!----!-----! !

! !DOORS !BIT STATUS 1! ! !No27! ! ! ! !

! !CLOSE ! energized ! ! ! ! ! ! ! !

! !SOLENOID ! ! ! ! ! ! ! ! !

! !SPLY -VE ! ! ! ! ! ! ! ! !

! !----------!------------!----!----!----!----!----!-----! !

! !DOORS !BIT STATUS 1! ! !No28! ! ! ! !

! !CLOSE ! energized ! ! ! ! ! ! ! !

! !SOLENOID ! ! ! ! ! ! ! ! !

! !SPLY 28V ! ! ! ! ! ! ! ! !

! !----------!------------!----!----!----!----!----!-----! !

! !SYSTEM !BIT STATUS 1! ! !No29! ! ! ! !

! !FAILED ! ! ! ! ! ! ! ! !

!--------------!----------!------------!----!----!----!----!----!-----!-------!

LGCIU 1/2 PARAMETER LIST EQPT 6D

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| PARAMETER LIST PARAMETER CHARACTERISTICS (NUMERIC) |

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! 1 022 01 !LGCIU ! ! ! ! 19 !100 !DIS ! !LGCIU !

! 2 022 10 !DISCRETE ! ! ! ! ! ! ! !1/2 !

! !WORD No3 ! ! ! ! ! ! ! ! !

! !----------!------------!----!----!----!----!----!-----!1,2,3 !

! !LH GEAR !BIT STATUS 1! ! !No11! ! ! ! !

! !NOT LKD UP! ! ! ! ! ! ! !32-31- !

! !----------!------------!----!----!----!----!----!-----!00 !

! !RH GEAR !BIT STATUS 1! ! !No12! ! ! ! !

! !NOT LKD UP! ! ! ! ! ! ! ! !

! !----------!------------!----!----!----!----!----!-----! !

! !NOSE GEAR !BIT STATUS 1! ! !No13! ! ! ! !

! !NOT LKD UP! ! ! ! ! ! ! ! !

! !----------!------------!----!----!----!----!----!-----! !

! !L/G SEL UP!BIT STATUS 1! ! !No14! ! ! ! !

! !(LEVER ! ! ! ! ! ! ! ! !

! !POSITION) ! ! ! ! ! ! ! ! !

! !----------!------------!----!----!----!----!----!-----! !

! !RETRACTION!BIT STATUS 1! ! !No15! ! ! ! !

! !INHIBITED ! ! ! ! ! ! ! ! !

! !----------!------------!----!----!----!----!----!-----! !

! !FWD CARGO !BIT STATUS 1! ! !No16! ! ! ! !

! !DOOR ! ! ! ! ! ! ! ! !

! !SAFETY ! ! ! ! ! ! ! ! !

! !MECHANISM ! ! ! ! ! ! ! ! !

! !SAFE *1 ! ! ! ! ! ! ! ! !

! !----------!------------!----!----!----!----!----!-----! !

! !AFT CARGO !BIT STATUS 1! ! !No17! ! ! ! !

! !DOOR ! ! ! ! ! ! ! ! !

! !SAFETY ! ! ! ! ! ! ! ! !

! !MECANISM ! ! ! ! ! ! ! ! !

! !SAFE *1 ! ! ! ! ! ! ! ! !

! !----------!------------!----!----!----!----!----!-----! !

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| PARAMETER LIST PARAMETER CHARACTERISTICS (NUMERIC) |

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! !FWD CARGO !BIT STATUS 1! ! !No18! ! ! ! !

! !DOOR ! ! ! ! ! ! ! ! !

! !LOCKING ! ! ! ! ! ! ! ! !

! !HANDLE ! ! ! ! ! ! ! ! !

! !LOCKED *1 ! ! ! ! ! ! ! ! !

! !----------!------------!----!----!----!----!----!-----! !

! !AFT CARGO !BIT STATUS 1! ! !No19! ! ! ! !

! !DOOR ! ! ! ! ! ! ! ! !

! !LOCKING ! ! ! ! ! ! ! ! !

! !HANDLE ! ! ! ! ! ! ! ! !

! !LOCKED *1 ! ! ! ! ! ! ! ! !

! !----------!------------!----!----!----!----!----!-----! !

! !FWD CARGO !BIT STATUS 1! ! !No20! ! ! ! !

! !DOOR ! ! ! ! ! ! ! ! !

! !LOCKING ! ! ! ! ! ! ! ! !

! !SHAFT ! ! ! ! ! ! ! ! !

! !NOT ! ! ! ! ! ! ! ! !

! !LOCKED *2 ! ! ! ! ! ! ! ! !

! !----------!------------!----!----!----!----!----!-----! !

! !AFT CARGO !BIT STATUS 1! ! !No21! ! ! ! !

! !DOOR ! ! ! ! ! ! ! ! !

! !LOCKING ! ! ! ! ! ! ! ! !

! !SHAFT ! ! ! ! ! ! ! ! !

! !NOT ! ! ! ! ! ! ! ! !

! !LOCKED *2 ! ! ! ! ! ! ! ! !

! !----------!------------!----!----!----!----!----!-----! !

! !LH GEAR !BIT STATUS 1! ! !No22! ! ! ! !

! !FORCED TO ! ! ! ! ! ! ! ! !

! !EXTENDED ! ! ! ! ! ! ! ! !

! !*3 ! ! ! ! ! ! ! ! !

! !----------!------------!----!----!----!----!----!-----! !

! !RH GEAR !BIT STATUS 1! ! !No23! ! ! ! !

! !FORCED TO ! ! ! ! ! ! ! ! !

! !EXTENDED ! ! ! ! ! ! ! ! !

! !*3 ! ! ! ! ! ! ! ! !

! !----------!------------!----!----!----!----!----!-----! !

! !NOSE GEAR !BIT STATUS 1! ! !No24! ! ! ! !

! !FORCED TO ! ! ! ! ! ! ! ! !

! !EXTENDED ! ! ! ! ! ! ! ! !

! !*3 ! ! ! ! ! ! ! ! !

! !----------!------------!----!----!----!----!----!-----! !

! !LH DOOR !BIT STATUS 1! ! !No25! ! ! ! !

! !FULLY OPEN! ! ! ! ! ! ! ! !

! !----------!------------!----!----!----!----!----!-----! !

! !RH DOOR !BIT STATUS 1! ! !No26! ! ! ! !

! !FULLY OPEN! ! ! ! ! ! ! ! !

! !----------!------------!----!----!----!----!----!-----! !

! !LH NOSE !BIT STATUS 1! ! !No27! ! ! ! !

! !DOOR ! ! ! ! ! ! ! ! !

! !FULLY OPEN! ! ! ! ! ! ! ! !

! !----------!------------!----!----!----!----!----!-----! !

! !RH NOSE !BIT STATUS 1! ! !No28! ! ! ! !

! !DOOR ! ! ! ! ! ! ! ! !

! !FULLY OPEN! ! ! ! ! ! ! ! !

! !----------!------------!----!----!----!----!----!-----! !

! !GEAR !BIT STATUS 1! ! !No29! ! ! ! !

! !FORCED TO ! ! ! ! ! ! ! ! !

! !UPLOCKED ! ! ! ! ! ! ! ! !

! !(NOSE OR ! ! ! ! ! ! ! ! !

! !LH OR RH) ! ! ! ! ! ! ! ! !

! !*3 ! ! ! ! ! ! ! ! !

!--------------!----------!------------!----!----!----!----!----!-----!-------!

! Remarks: !

! *1 Only sent by LGCIU-1. !

! *2 Only sent by LGCIU-2. !

! *3 Output signal caused by a failure in a LGCIUs related proximity !

! detection circuit. !

!-----------------------------------------------------------------------------!

LGCIU 1/2 PARAMETER LIST EQPT 6D

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| PARAMETER LIST PARAMETER CHARACTERISTICS (NUMERIC) |

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! 1 023 01 !LGCIU ! ! ! ! 4 !100 !DIS ! !LGCIU !

! 2 023 10 !DISCRETE ! ! ! ! ! ! ! !1/2 !

! !WORD No4 ! ! ! ! ! ! ! ! !

! !----------!------------!----!----!----!----!----!-----!1,2,3 !

! ! SPARE ! ! ! !No11! ! ! ! !

! ! ! ! ! !THRU! ! ! !32-31- !

! ! ! ! ! !No20! ! ! !00 !

! !----------!------------!----!----!----!----!----!-----! !

! !LH FLAP !BIT STATUS 1! ! !No21! ! ! ! !

! !CONNECTED ! ! ! ! ! ! ! ! !

! !----------!------------!----!----!----!----!----!-----! !

! !LH FLAP !BIT STATUS 1! ! !No22! ! ! ! !

! !PROXIMITY ! ! ! ! ! ! ! ! !

! !SENSOR ! ! ! ! ! ! ! ! !

! !SERVICE- ! ! ! ! ! ! ! ! !

! !ABLE ! ! ! ! ! ! ! ! !

! !----------!------------!----!----!----!----!----!-----! !

! ! SPARE ! ! ! !No23! ! ! ! !

! !----------!------------!----!----!----!----!----!-----! !

! ! SPARE ! ! ! !No24! ! ! ! !

! !----------!------------!----!----!----!----!----!-----! !

! !RH FLAP !BIT STATUS 1! ! !No25! ! ! ! !

! !CONNECTED ! ! ! ! ! ! ! ! !

! !----------!------------!----!----!----!----!----!-----! !

! !RH FLAP !BIT STATUS 1! ! !No26! ! ! ! !

! !PROXIMITY ! ! ! ! ! ! ! ! !

! !SENSOR ! ! ! ! ! ! ! ! !

! !SERVICE- ! ! ! ! ! ! ! ! !

! !ABLE ! ! ! ! ! ! ! ! !

! !----------!------------!----!----!----!----!----!-----! !

! !PAD BIT !BIT STATUS 1! ! !No27! ! ! ! !

! !ALWAYS 1 ! ! ! ! ! ! ! ! !

! !----------!------------!----!----!----!----!----!-----! !

! !PROXIMITY !BIT STATUS 1! ! !No28! ! ! ! !

! !SENSOR ! ! ! ! ! ! ! ! !

! !DISAGREE ! ! ! ! ! ! ! ! !

! !----------!------------!----!----!----!----!----!-----! !

! !SYSTEM !BIT STATUS 1! ! !No29! ! ! ! !

! !FAULT ! ! ! ! ! ! ! ! !

! !----------!------------!----!----!----!----!----!-----! !

LGCIU 1/2 PARAMETER LIST EQPT 6D

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| PARAMETER LIST PARAMETER CHARACTERISTICS (NUMERIC) |

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! 1 356 01 !MAINTENAN-! ! ! ! !100 !ISO5! !LGCIU !

! 2 356 10 !CE ! ! ! ! ! ! ! !1/2 !

! !MESSAGES ! ! ! ! ! ! ! ! !

!--------------!----------!------------!----!----!----!----!----!---- !1,2,3 !

! 1 377 01 !EQPT !bits 11-14 ! ! !2(1)!100 !HEX ! ! !

! 2 377 10 !IDENT !low part ! ! ! ! ! ! !32-31- !

! ! !bits 15-18 ! ! ! ! ! ! !00 !

! ! !high part ! ! ! ! ! ! ! !

! ! !bits 19-29 ! ! ! ! ! ! ! !

! ! !logic '0' ! ! ! ! ! ! ! !

!--------------!----------!------------!----!----!----!----!----!-----!-------!

!Remarks: !

!(1) = Significant Data Digits !

!-----------------------------------------------------------------------------!

** ON A/C NOT FOR ALL

6. Component Description

A. Cockpit Panel

Landing Gear Position Indicator Lights (8GB/9GB/10GB) ** ON A/C NOT FOR ALL

ECAM Display ** ON A/C NOT FOR ALL

ECAM WHEEL Page - System Failure Indications ** ON A/C NOT FOR ALL

Landing Gear Position Indicator Lights (8GB/9GB/10GB) ** ON A/C NOT FOR ALL

ECAM Display ** ON A/C NOT FOR ALL

ECAM WHEEL Page - System Failure Indications ** ON A/C NOT FOR ALL

(1) ECAM WHEEL Page

The ECAM system uses L/G position data to give the WHEEL page display on the lower ECAM DU. The data from the two systems is used to make an analysis, to give these indications:

(a) Normal Indications

The ECAM WHEEL page shows three sets of colored indicators. Each set of indicators has:

two triangles that show the L/G position (one triangle for each LGCIU system)
a moving hinged bar that shows the L/G door position.

The triangles are:

green when the L/G is down and locked
red when the L/G is in transit
not in view when the L/G is up and locked.

A green triangle will always be more important than a red triangle. Thus a green triangle shows as the front triangle.

The hinged bars are:

green when the door is closed
amber when the door is not closed.

An amber indication, L/G CTL shows when the L/G is not locked in its set position.

(b) Failure Indications

When specified failures occur the WHEEL page shows (in amber):

the indication UPLOCK (above the applicable L/G and L/G door indicator)
X legends. Two X legends can replace each L/G or L/G door indicator.

The failure conditions that cause the indication/legends to show are given in paragraph 7.B. L/G System Warnings.

(2) ECAM WHEEL Page

The ECAM system uses L/G position data to give the WHEEL page display on the lower ECAM DU. The data from the two systems is used to make an analysis, to give these indications:

(a) Normal Indications

The ECAM WHEEL page shows three sets of colored indicators. Each set of indicators has:

two triangles that show the L/G position (one triangle for each LGCIU system)
a moving hinged bar that shows the L/G door position.

The triangles are:

green when the L/G is down and locked
red when the L/G is in transit
not in view when the L/G is up and locked.

A green triangle will always be more important than a red triangle. Thus a green triangle shows as the left triangle and a red triangle shows as the right triangle.

The hinged bars are:

green when the door is closed
amber when the door is not closed.

An amber indication, L/G CTL shows when the L/G is not locked in its set position.

(b) Failure Indications

When specified failures occur the WHEEL page shows (in amber):

the indication UPLOCK (above the applicable L/G and L/G door indicator)
X legends. Two X legends can replace each L/G or L/G door indicator.

The failure conditions that cause the indication/legends to show are given in paragraph 7.B. L/G System Warnings.

(3) L/G Position Indicating Light Units (8GB/9GB/10GB).

The three sets of indicator lights are installed in 402VU panel. This panel is on the main instrument panel above the L/G control-lever (6GA).
Each set of indicator lights shows the position of a single L/G as follows:

red, L/G not locked in the selected position
green, L/G down and locked.

B. L/G Control-Lever FIN: 6-GA

Cockpit Component Location ** ON A/C NOT FOR ALL

(1) Control Lever DOWN Arrow

The red DOWN arrow has internal lighting. This comes on when the L/G is not extended and the engines and flight controls are in a landing configuration.

** ON A/C NOT FOR ALL

7. Operation/Control and Indicating

A. Normal System Indications

The L/G and L/G door indicators on the WHEEL page show the position of the L/G and the L/G doors. The WHEEL page automatically shows:

between the first engine start and the first engine at takeoff power
between the selection of DOWN or 800 ft radio height (whichever is the first to occur) and the second engine shut down.

The L/G position-indicator lights (8GB/9GB/10GB) show the position of the MLG and NLG.

At the start of a L/G retraction sequence with the L/G control-lever (6GA) set to UP:

the red indicator lights come on
the green indicator lights stay on.

The green indicator lights stay on until a L/G doors fully open signal causes the LGCIU to signal the L/G to retract. This releases the downlocks.

B. L/G System Warnings

ECAM WHEEL Page - System Failure Indications ** ON A/C NOT FOR ALL

The messages that follow can appear automatically on the Engine/Warning Display (Ref. AMM D/O 31-66-00-00):

LGCIU 1(2) FAULT
L/G SHOCK ABSORBER FAULT
L/G NOT DOWNLOCKED
L/G NOT UPLOCKED
L/G DOOR NOT CLOSED
L/G NOT DOWN
L/G UPLOCK FAULT
L/G SYS DISAGREE

The paragraphs that follow describe:

the conditions that cause each warning message
the visual and aural warnings and system indications given with each message.

(1) LGCIU 1 (2) FAULT

This warning message shows if during flight:

a LGCIU failure occurs
a failure occurs in the LGCIUs L/G control and position sensing system (e.g. an electrical failure of a proximity sensor).

When these failures occur the WHEEL page shows two amber X legends at each L/G indication position.

NOTE: The WHEEL page also shows these two amber X legends if a LGCIU is turned off (Refer to the MMEL).

(2) L/G SHOCK ABSORBER FAULT

(a) If a shock absorber does not extend (as detected by both SYSTEM 1 and SYSTEM 2).

1 The movement of the L/G control-lever to UP is baulked.

2 5 seconds after the aircraft enters flight phase 5 the failure warning message L/G SHOCK ABSORBER FAULT shows (on the upper ECAM DU) and:
- the master caution (amber) lights come on
- a single chime sounds.

(b) If a shock absorber did not compress when the aircraft was on the ground (as detected by both SYSTEM 1 and SYSTEM 2) the warnings as specified above occur.

the retraction cycle stops
the warnings as specified above occur immediately.

NOTE: If SYSTEM 1 and SYSTEM 2 do not agree on shock absorber extension (as signalled by the proximity sensors), the selection of L/G UP is not baulked.

(3) L/G NOT DOWNLOCKED, L/G NOT UPLOCKED, L/G DOOR NOT CLOSED

When one or more of the L/G or L/G doors do not lock (or stay locked) in the selected position (as detected by both SYSTEM 1 and SYSTEM 2):

the applicable warning message shows
the applicable red master warning or amber caution light comes on (red for L/G not down and locked, and amber for the other conditions)
an aural warning sounds (a continuous repetitive chime with the red master warning lights or a single chime with the amber caution lights)
the WHEEL page shows (if a L/G does not downlock, the selection of DOWN will cause the WHEEL page to show).

When the warning messages L/G NOT DOWNLOCKED or L/G NOT UPLOCKED show, the WHEEL page shows:

the message L/G CTL
two red triangles at the applicable L/G indication position(s).

When the warning message L/G DOOR NOT CLOSED shows, the WHEEL page shows, an amber bar. This is for applicable L/G door indication position(s).

If a L/G does not lock in the selected position (as detected by SYSTEM 1) the applicable red indicator light (402VU panel) stays on.

(4) L/G NOT DOWN - L/G Configuration Warning

The FWCs and ECAM supply the L/G configuration warning L/G NOT DOWN.

To do this input signals are used from:

the SYSTEM 1 and SYSTEM 2 Landing Gear Control and Interface Units (LGCIU)
the SYSTEM 1 and SYSTEM 2 Full Authority Digital Engine Control Systems (FADEC)
the Slat and Flap Instrumentation Position Pick-Off Units (IPPU)
the SYSTEM 1 and SYSTEM 2 Radio Altimeters.

When the aircraft is in one of the configurations that follow, the FWCs and the ECAM system will:

put the red master warning lights on
show the warning message L/G NOT DOWN on the upper ECAM DU
sound a continuous repetitive chime
put the red down arrow on (L/G control-lever). The red down arrow does not come on when the aircraft is in flight phase 4, 5 and 6 (when a minimum of one radio altimeter is serviceable).

The warning L/G NOT DOWN occurs when the L/G is not locked down and a mimimum of one LGCIU is serviceable and:

(a) The aircraft is below 750 ft radio height with the engines not at takeoff power and it has one of these conditions:

two engines below 75% RPM
one engine below 97% RPM with the other ENG/MASTER control switch in the OFF position
and the conditions of paragraphs (b) and (c) are not applicable.

When these conditions cause a warning to occur it is possible to cancel the warning as follows:

----------------------------------------------------------------------------

! ! RESULT !

! !--------------------------------------!

! ! Cancels Cancels Cancels Cancels !

! ACTION ! Aural Master ECAM DOWN !

! ! Warning? Warning Message? Arrow? !

! ! Lights? !

!-------------------------------------!--------------------------------------!

! Correction of A/C Configuration ! YES YES YES YES !

!-------------------------------------!--------------------------------------!

! Use of the Emergency Aural Cancel ! !

! P/BSW (master warning light P/BSW) ! YES YES NO NO !

!-------------------------------------!--------------------------------------!

! Use of the ECAM EMER CANC P/BSW ! YES YES NO NO !

!-------------------------------------!--------------------------------------!

! Use of the CLR P/BSW (ECAM Control ! NO NO YES NO !

! Panel) ! !

----------------------------------------------------------------------------

(b) The aircraft is below 750 ft radio height with:

a flap position of 18 degrees or larger and a slat position of 16 degrees or larger
engines not at takeoff power.

and has a flap position of 24 degrees or larger and a slat position of 24 degrees or larger.

When these conditions (as specified in (b) and (c)) cause a warning to occur, it is possible to cancel the warning as follows:

----------------------------------------------------------------------------

! ! RESULT !

! !--------------------------------------!

! ! Cancels Cancels Cancels Cancels !

! ACTION ! Aural Master ECAM DOWN !

! ! Warning? Warning Message? Arrow? !

! ! Lights? !

!-------------------------------------!--------------------------------------!

! Correction of A/C Configuration ! YES YES YES YES !

!-------------------------------------!--------------------------------------!

! Use of the Emergency Aural Cancel ! !

! P/BSW (master warning light P/BSW) ! NO NO NO NO !

!-------------------------------------!--------------------------------------!

! Use of the ECAM EMER CANC P/BSW ! YES YES NO NO !

!-------------------------------------!--------------------------------------!

! Use of the CLR P/BSW (ECAM Control ! NO NO YES NO !

! Panel) ! !

----------------------------------------------------------------------------

NOTE: 1. The ECAM EMER CANC pushbutton switch is only used to cancel false warnings.
2. After you cancel an aural warning a subsequent deterioration in the conditions (as specified above) will cause the aural warning to occur again.

(5) L/G NOT DOWN - L/G Configuration Warning

The FWCs and ECAM supply the L/G configuration warning L/G NOT DOWN.

To do this input signals are used from:

the SYSTEM 1 and SYSTEM 2 Landing Gear Control and Interface Units (LGCIU)
the SYSTEM 1 and SYSTEM 2 Full Authority Digital Engine Control Systems (FADEC)
the Slat and Flap Instrumentation Position Pick-Off Units (IPPU)
the SYSTEM 1 and SYSTEM 2 Radio Altimeters.

When the aircraft is in one of the configurations that follow, the FWCs and the ECAM system will:

put the red master warning lights on
show the warning message L/G NOT DOWN on the upper ECAM DU
sound a continuous repetitive chime
put the red down arrow on (L/G control-lever). The red down arrow does not come on when the aircraft is in flight phase 4, 5 and 6 (when a minimum of one radio altimeter is serviceable).

The warning L/G NOT DOWN occurs when the L/G is not locked down and a mimimum of one LGCIU is serviceable and:

(a) The aircraft is below 750 ft radio height with the engines not at takeoff power and it has one of these conditions:

two engines below 75% RPM
one engine below 97% RPM with the other ENG/MASTER control switch in the OFF position
and the conditions of paragraphs (b) and (c) are not applicable.

When these conditions cause a warning to occur it is possible to cancel the warning as follows:

----------------------------------------------------------------------------

! ! RESULT !

! !--------------------------------------!

! ! Cancels Cancels Cancels Cancels !

! ACTION ! Aural Master ECAM DOWN !

! ! Warning? Warning Message? Arrow !

! ! Lights? !

!-------------------------------------!--------------------------------------!

! Correction of A/C Configuration ! YES YES YES YES !

!-------------------------------------!--------------------------------------!

! Use of the Emergency Aural Cancel ! !

! P/BSW (master warning light P/BSW) ! YES YES NO NO !

!-------------------------------------!--------------------------------------!

! Use of the ECAM EMER CANC P/BSW ! YES YES NO NO !

!-------------------------------------!--------------------------------------!

! Use of the CLR P/BSW (ECAM Control ! NO NO YES NO !

! Panel) ! !

----------------------------------------------------------------------------

(b) The aircraft is below 750 ft radio height with:

a flap position of 19 degrees or larger and a slat position of 16 degrees or larger
engines not at takeoff power.

and has a flap position of 23 degrees or larger and a slat position of 24 degrees or larger.

When these conditions (as specified in (b) and (c)) cause a warning to occur, it is possible to cancel the warning as follows:

----------------------------------------------------------------------------

! ! RESULT !

! !--------------------------------------!

! ! Cancels Cancels Cancels Cancels !

! ACTION ! Aural Master ECAM DOWN !

! ! Warning? Warning Message? Arrow? !

! ! Lights? !

!-------------------------------------!--------------------------------------!

! Correction of A/C Configuration ! YES YES YES YES !

!-------------------------------------!--------------------------------------!

! Use of the Emergency Aural Cancel ! !

! P/BSW (master warning light P/BSW ! NO NO NO NO !

!-------------------------------------!--------------------------------------!

! Use of the ECAM EMER CANC P/BSW ! YES YES NO NO !

!-------------------------------------!--------------------------------------!

! Use of the CLR P/BSW (ECAM Control ! NO NO YES NO !

! Panel) ! !

---------------------------------------------------------------------------

(6) L/G UPLOCK FAULT

This warning message shows if SYSTEM 1 and SYSTEM 2 detect that a gear uplock has closed when the L/G is downlocked (e.g. because of a maintenance task/failure of the uplock mechanism) and:

the master caution (amber) lights come on
a single chime sounds
the WHEEL page shows.

To identify which uplock has closed (or is defective) the WHEEL page shows these amber legends:

the message UPLOCK above the applicable L/G indication
four X's at the applicable L/G indication position. (The two green triangles do not show at the same time as the X legends).

(7) L/G SYS DISAGREE

The ECAM system compares the L/G (gear only) position data from SYSTEM 1 and SYSTEM 2. When there is a difference in this data (eg because of a proximity sensor failure) it shows the warning message L/G SYS DISAGREE and the WHEEL page.

C. WHEEL Page - Single System Failure Indications

ECAM WHEEL Page - System Failure Indications ** ON A/C NOT FOR ALL

When one of the two systems detects that a mechanical failure has occurred in:

a L/G downlock
a L/G uplock
a L/G door uplock

the indications that follow show.

The WHEEL page shows (in amber) the message UPLOCK (above the applicable L/G indication) and two X legends (at the applicable L/G indication position) if SYSTEM 1 or SYSTEM 2 tells the ECAM system that:

a L/G uplock has closed when the MLG and NLG are down locked
a L/G is locked down when the MLG and NLG are locked up.

The WHEEL page also shows two amber X legends at the applicable L/G door indication position if:

SYSTEM 1 or SYSTEM 2 tell the ECAM system that a L/G door is fully open (when the MLG and NLG are locked up) and all the L/G doors are locked closed.

No visual (ECAM message, master warning/caution lights) or aural warnings are given when these failure conditions occur.

D. L/G Free-Fall Extension

When a free-fall extension of the L/G occurs, the green position indicator lights come on. This shows that the MLG and NLG are locked down.

NOTE: When the positions of the L/G and the L/G control-lever do not agree, (eg the MLG and NLG are in transit or locked down and the control-lever is in the UP position), the red position indicator lights come on.

If the WHEEL page does not show on the lower ECAM DU as the free-fall extension occurs:

it automatically shows after 30 seconds
and shows six green triangles and three L/G doors fully open or L/G doors in transit indications.

These warning messages also show on the upper ECAM DU:

L/G DOOR NOT CLOSED
MAX SPEED 250

** ON A/C NOT FOR ALL

8. BITE Test
Not applicable

[Rev.10 from 2021] 2026.04.01 12:29:43 UTC