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AIRCRAFT SYSTEMS

LANDING GEAR
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 AIRCRAFT SYSTEMS
LANDING GEAR
A319/A320/A321
FLIGHT CREW
OPERATING MANUAL
UNOFFICIAL COPY PRELIMINARY PAGES - TABLE OF CONTENTS

DSC-32-10 Gears and Doors

DSC-32-10-10 Description
General.....................................................................................................................................................................A
Main Landing Gear (MLG)...................................................................................................................................... B
Nose Landing Gear (NLG)...................................................................................................................................... C
Landing Gear Extension and Retraction Equipment...............................................................................................D
Landing Gears and Doors Operation...................................................................................................................... E

DSC-32-10-20 Landing Gear System/Interface

Landing Gear Control Interface Unit (LGCIU).........................................................................................................A
Proximity Detector Output Signals.......................................................................................................................... B
Proximity Detector Output Signals (Cont'd)............................................................................................................ C

DSC-32-10-30 Interactions between Landing Gear and Aircraft Systems

GENERAL................................................................................................................................................................ A
Proximity Detectors on Shock Absorbers................................................................................................................B
Proximity Detectors on Uplocks.............................................................................................................................. C
Proximity Detectors on Doors................................................................................................................................. D
Proximity Detectors on Downlocks..........................................................................................................................E
Proximity Detectors on Cargo Doors.......................................................................................................................F
Proximity Detectors on Flaps Attachments.............................................................................................................G

DSC-32-10-40 Controls and Indicators

Landing Gear Indicator Panel..................................................................................................................................A
Landing Gear Selector Lever.................................................................................................................................. B
Landing Gear Gravity Extension............................................................................................................................. C
WHEEL SD Page.................................................................................................................................................... D
Memo Display.......................................................................................................................................................... E

DSC-32-20 Nose Wheel Steering

DSC-32-20-10 Description
Description............................................................................................................................................................... A
Architecture.............................................................................................................................................................. B

DSC-32-20-20 Controls and Indicators

Side Consoles..........................................................................................................................................................A
WHEEL SD Page.................................................................................................................................................... B
Memo Display.......................................................................................................................................................... C
Continued on the following page

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LANDING GEAR
A319/A320/A321
FLIGHT CREW
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PRELIMINARY PAGES - TABLE OF CONTENTS

Continued from the previous page

DSC-32-30 Brakes and Antiskid
DSC-32-30-10 Description
General.....................................................................................................................................................................A
Anti-Skid System......................................................................................................................................................B
Auto Brake............................................................................................................................................................... C
Braking Modes.........................................................................................................................................................D
Braking Schematic................................................................................................................................................... E

DSC-32-30-20 Controls and Indicators

Center Instrument Panel..........................................................................................................................................A
Auto BRK Panel.......................................................................................................................................................B
Brake Fan  .......................................................................................................................................................C
Pedestal................................................................................................................................................................... D
WHEEL SD Page.................................................................................................................................................... E
Audio Indicators....................................................................................................................................................... F
Memo Display..........................................................................................................................................................G

DSC-32-40 Tire Pressure Indicating System

DSC-32-40-10 Description
Description............................................................................................................................................................... A

DSC-32-40-20 Controls and Indicators

WHEEL SD Page.................................................................................................................................................... A

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FLIGHT CREW
OPERATING MANUAL
UNOFFICIAL COPY
PRELIMINARY PAGES - SUMMARY OF HIGHLIGHTS

Localization Toc ID Reason

Title Index
DSC-32-10-30 B 1 Layout modification. No technical change.
Proximity Detectors on Shock Wording enhancement. No technical change.
Absorbers Update of the windshields, windows and probes that are heated
on ground and in flight, to be in accordance with the aircraft
system.
DSC-32-30-10 C 1 Effectivity update: The information now also applies to TC-LBK,
Auto Brake - System Arming TLBI, TC-LPR.
DSC-32-30-10 C 2 Effectivity update: The information now also applies to TC-LBK,
Auto Brake - System Activation TLBI, TC-LPR.
DSC-32-30-20 B 1 Effectivity update: The information now also applies to TC-JLT,
Auto BRK Panel TC-LBK, TLBI, TC-LPR.
DSC-32-30-20 F 2 Effectivity update: The information now also applies to TC-JPP,
Audio Indicators TC-LSN, TC-LSS, TC-LSU, TC-LSY.
DSC-32-30-20 G 3 Effectivity update: The information no longer applies to TC-JPP,
AUTO BRK OFF TC-LSN, TC-LSS, TC-LSU, TC-LSY.
DSC-32-30-20 G 4 Effectivity update: The information now also applies to TC-JPP,
AUTO BRK OFF TC-LSN, TC-LSS, TC-LSU, TC-LSY.
DSC-32-40-10 A 1 Effectivity update: The information now also applies to TC-LPR.
Description
DSC-32-40-20 A 1 Effectivity update: The information now also applies to TC-LPR.
WHEEL SD Page

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UNOFFICIAL COPY GEARS AND DOORS - DESCRIPTION

GENERAL
Ident.: DSC-32-10-10-00018598.0001001 / 21 MAR 16
Applicable to: ALL

The landing gear consists of :

‐ Two main landing gears that retract inboard
‐ One nose landing gear that retracts forward.
Doors enclose the landing gear bays. Gear and doors are electrically controlled and hydraulically
operated.
The doors, which are fitted to the landing gear struts, are operated mechanically by the gear and
close at the end of gear retraction.
All gear doors open while the gear is retracting or extending.
Two Landing Gear Control and Interface Units (LGCIUs) control the extension and retraction of the
gear and the operation of the doors. They also supply information about the landing gear to ECAM
for display, and send signals indicating whether the aircraft is in flight or on the ground to other
aircraft systems.
A hand crank on the center pedestal allows the flight crew to extend the landing gear if the aircraft
loses hydraulic systems or electrical power.

MAIN LANDING GEAR (MLG)

Ident.: DSC-32-10-10-00018599.0001001 / 21 MAR 16
Applicable to: ALL

Each main gear has twin wheels and an oleopneumatic shock absorber.
Each main wheel has an antiskid brake.

NOSE LANDING GEAR (NLG)

Ident.: DSC-32-10-10-00018600.0001001 / 21 MAR 16
Applicable to: ALL

The two-wheeled nose gear has an oleopneumatic shock strut and a nose wheel steering system.

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GEARS AND DOORS - DESCRIPTION

LANDING GEAR EXTENSION AND RETRACTION EQUIPMENT

Ident.: DSC-32-10-10-00018601.0001001 / 21 MAR 16
Applicable to: ALL

MAIN LANDING GEAR

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A319/A320/A321
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OPERATING MANUAL
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NOSE LANDING GEAR

LANDING GEARS AND DOORS OPERATION

Applicable to: ALL
Ident.: DSC-32-10-10-A-00018602.0001001 / 12 AUG 24

NORMAL OPERATION
The flight crew normally operates the landing gear by means of the lever on the center instrument
panel.
The LGCIUs control the sequencing of gear and doors electrically. One LGCIU controls one
complete gear cycle, then switches over automatically to the other LGCIU at the completion of the
retraction cycle. It also switches over in case of failure.
The green hydraulic system actuates all gear and doors. When the aircraft speed is above 264 kt,
a safety valve automatically cuts off hydraulic supply to the landing gear system. Below 260 kt, the
hydraulic supply remains cut off as long as the landing gear lever is up.

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GEARS AND DOORS - DESCRIPTION

Ident.: DSC-32-10-10-A-00018603.0001001 / 21 MAR 16

LANDING GEAR GRAVITY EXTENSION

If the normal system fails to extend the landing gear hydraulically, the flight crew can use a crank
to extend it mechanically.
When a crew member turns the crank, it :
‐ Isolates the landing gear hydraulics from the green hydraulic system
‐ Unlocks the landing gear doors and the main and nose main gear
‐ Allows gravity to drop the gear into the extended position.
Locking springs help the crew to crank the main gear into the locked condition, and aerodynamic
forces assist in the locking of the nose gear.

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A319/A320/A321
FLIGHT CREW
OPERATING MANUAL
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The gear doors remain open.

The flight crew can reset the emergency extension system in flight after using it for training (if
green hydraulic pressure is available).

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OPERATING MANUAL
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GEARS AND DOORS - LANDING GEAR SYSTEM/INTERFACE

LANDING GEAR CONTROL INTERFACE UNIT (LGCIU)

Applicable to: ALL
Ident.: DSC-32-10-20-A-00018604.0001001 / 21 MAR 16

GENERAL
The LGCIUs receive position information from the landing gear, cargo door, and landing flap
systems.
Ident.: DSC-32-10-20-A-00018605.0001001 / 21 MAR 16

LANDING GEAR INFORMATION

The LGCIUs receive landing gear position information from proximity detectors when:
‐ The landing gears are locked down or up, or
‐ The shock absorbers are compressed or extended, or
‐ The landing gear doors are open, or closed, or
‐ The bogie are aligned or not.
The LGCIUs send the landing gear position data to other aircraft systems.
In case of a LGCIU failure, the landing gear is controlled by the remaining healthy LGCIU.
Ident.: DSC-32-10-20-A-00018606.0001001 / 22 FEB 22

CARGO DOORS INFORMATION

Sensors send to the LGCIUs the position of the following components :
‐ Manual selector valves
‐ Locking shaft
‐ Locking handle
‐ Safety shaft
‐ Door sills  .
The LGCIUs detect electrical failures only in certain proximity switches in the cargo door system :
‐ Locking shaft
‐ Locking handle
‐ Safety shaft.
When an LGCIU makes such a detection, it indicates the NON LOCKED condition for that
component.
Ident.: DSC-32-10-20-A-00018607.0001001 / 21 MAR 16

LANDING FLAPS INFORMATION

The LGCIUs process the signals from four flap disconnect proximity switches, then send them to
the Slat/Flap Control Computers (SFCCs).
The LGCIUs do not monitor failures in the SFCC system.

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OPERATING MANUAL
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GEARS AND DOORS - LANDING GEAR SYSTEM/INTERFACE

PROXIMITY DETECTOR OUTPUT SIGNALS

Ident.: DSC-32-10-20-00001278.0001001 / 22 MAY 12
Applicable to: ALL

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GEARS AND DOORS - LANDING GEAR SYSTEM/INTERFACE

PROXIMITY DETECTOR OUTPUT SIGNALS (CONT'D)

Ident.: DSC-32-10-20-00001279.0001001 / 21 MAR 16
Applicable to: ALL

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LANDING GEAR
A319/A320/A321 GEARS AND DOORS - INTERACTIONS BETWEEN
FLIGHT CREW
OPERATING MANUAL
UNOFFICIAL COPY LANDING GEAR AND AIRCRAFT SYSTEMS

GENERAL
Ident.: DSC-32-10-30-00001285.0001001 / 10 DEC 09
Applicable to: ALL

The following tables present the operational effects of the proximity detectors on aircraft systems.
How to read the tables :
SYSTEM LGCIU 1 LGCIU 2 A/C IN FLT A/C ON GROUND
SERVICE INTERPHONE 6 6 ........ ........
SFCC 1(2) 5 (5) ........ ........

The above lines mean that the service interphone receives the output n° 6 from both LGCIUs, while
SFCC 1 receive the output 5 from LGCIU 1 and SFCC 2 the output 5 from LGCIU 2.
The two additional columns give the system functioning when the aircraft is in flight and on the
ground.

PROXIMITY DETECTORS ON SHOCK ABSORBERS

Ident.: DSC-32-10-30-00018608.0001001 / 06 JUN 22
Applicable to: TC-JTS, TC-JTT, TC-JTU, TC-LBA, TC-LBB, TC-LBC, TC-LBD, TC-LBF, TC-LBG, TC-LBH, TC-LBJ, TC-LBK, TC-LPA,
TC-LPB, TC-LPC, TC-LPD, TC-LPE, TC-LPF, TC-LPG, TC-LPH, TC-LPI, TC-LPJ, TC-LPK, TC-LPL, TC-LPM, TC-LPN, TC-LPO, TC-LPP,
TC-LPR, TC-LSA, TC-LSB, TC-LSC, TC-LSD, TC-LSE, TC-LSF, TC-LSG, TC-LSH, TC-LSJ, TC-LSK, TC-LSL, TC-LSM, TC-LSN, TC-LSO,
TC-LSP, TC-LSR, TC-LSS, TC-LST, TC-LSU, TC-LSV, TC-LSY, TC-LSZ, TC-LTA, TC-LTB, TC-LTC, TC-LTD, TC-LTE, TC-LTF, TC-LTG,
TC-LTH, TC-LTI, TC-LTJ, TC-LTK, TC-LTL, TC-LTM, TC-LTN, TC-LTO, TC-LTP, TC-LTR, TC-LTS, TC-LTT, TC-LTU, TC-LTV, TC-LTY,
TC-LTZ, TC-LUA, TC-LUB, TC-LUC, TC-LUE, TC-LUI, TC-LUJ, TC-LUK, TC-LUL, TC-LUM, TC-LUN, TC-LUO, TC-LUP, TC-LUR, TC-LUS,
TC-LUU, TC-LUV, TC-LUY, TC-LUZ, TLBI

LGCIU 1 LGCIU 2
SYSTEM A/C IN FLT A/C ON GRND
OUTPUT OUTPUT
STROBE lights 5 On when AUTO selected Off when AUTO selected
LOGO lights 5 Off when flaps retracted On
AIRSTAIRS
3 1 Control inhibited(1) Control not inhibited(2)

GENERAL
CARGO Normal control
5 Normal control available
DOOR(5) not available
WATER Preselect water Preselect water
5
FILLING servicing inhibited servicing available
Continued on the following page

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LANDING GEAR
A319/A320/A321 GEARS AND DOORS - INTERACTIONS BETWEEN
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OPERATING MANUAL
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LANDING GEAR AND AIRCRAFT SYSTEMS
Continued from the previous page
LGCIU 1 LGCIU 2
SYSTEM A/C IN FLT A/C ON GRND
OUTPUT OUTPUT
• Skin temperature • Skin temperature < 9 °C
< 32 °C : The : The system is in closed
system is in closed configuration(2)
AVNCS configuration(1) • Skin temperature > 12 °C
5 5
COOLING • Skin temperature > : The system is in open
35 °C : The system configuration(2)
is in intermediate
configuration(1)
GRND 1 1
Inhibited(1) Not inhibited(2)
AIR COND COOLING  3 3
FWD CARGO Extract fan stopped
5 Extract fan on
VENT when ΔP > 1 PSI
‐ Prepressurization active
before TO (3)
CAB PRESS 5 5 Climb mode active (4)
‐ Depressurization active
after LDG (3)
PACK 1(2)
3 Pack air inlet Pack air inlet flap fully
TEMP
(1) flaps opened. closed at TO and LDG
CONTROL
In case of oil low
pressure, the automatic
In case of oil low
shutdown is delayed by:
APU AUTO pressure, automatic
• 15.5 s if the oil
SHUTDOWN shutdown is
temperature < -4 °C
delayed by 15.5 s
• 0.05 s if oil temperature
APU 5
> -4 °C
Speed is controlled at
99 % (100 % for ENG start
APU SPEED Speed is controlled
or when ambient
CONTROL at 100 %
temperature is below
-18 °C or above 35 °C)
Continued on the following page

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LANDING GEAR
A319/A320/A321 GEARS AND DOORS - INTERACTIONS BETWEEN
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OPERATING MANUAL
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Continued from the previous page
LGCIU 1 LGCIU 2
SYSTEM A/C IN FLT A/C ON GRND
OUTPUT OUTPUT
SERVICE
6 6 Inhibited(6) Available(7)
INTERPHONE
PUBLIC
1 1
ADDRESS PA increased level(6) PA low level(7)
3 3
(PA)
ADIRU and
1 1 External horn and External horn and
AVIONICS
3 3 light inhibited(6) light not inhibited(7)
ground warning
Communication
FLT Communication with
9 with ground
INTERPHONE ground mechanic available
mechanic inhibited
COCKPIT
9 Inhibited Not inhibited
CALL LIGHT
ACARS
(ACARS MU 7 Available Available
or ATSU)
COMMUNICATIONS
Runs : (7)
‐ During the first 5 min
following energization
1
1 ‐ With at least one engine
CVR 3 Runs(6)
3 running
7
Stops : (7)
5 min after second engine
shutdown
• ERASE function • ERASE function not
inhibited inhibited
• No low frequency • Low frequency signal in
CVR 5
signal in the the loudspeakers if test
loudspeakers if test performed
performed
APU start on batteries No APU start delay
DC generation 5
only, is delayed by 45 s when on batteries only
ELEC Main galley not supplied Main galley supplied when
GALLEY
5 when APU GEN APU GEN only is supplying
supply
only is supplying
Display test inhibited
EIS EIS 5 when ANN LT Display test not inhibited
TEST is selected
No APU fire automatic Automatic extinguishing
FIRE APU 5
extinguishing not inhibited
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LANDING GEAR
A319/A320/A321 GEARS AND DOORS - INTERACTIONS BETWEEN
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OPERATING MANUAL
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LANDING GEAR AND AIRCRAFT SYSTEMS
Continued from the previous page
LGCIU 1 LGCIU 2
SYSTEM A/C IN FLT A/C ON GRND
OUTPUT OUTPUT
• For SFCC 1(2): • For SFCC 1(2):
Slats alpha/speed lock Slats alpha/speed lock
function active function active if speed >
• For SFCC(2): 60 kt
FLT CTL SFCC 1(2) 5 (5)
No flaps movement • For SFCC (2):
inhibition if the cargo Flaps movement
door is opened inhibition if cargo door is
opened

Runs: (7)
• During the first 5 min
1 following energization
• DFDR 1
FLT INST • QAR 
3
3
Runs(6) • With one engine running
7
Stops: (7)
5 min after second engine
shut down
FQI uses flight
FQI uses ground
FUEL FQI 5 attitude correction
attitude correction
due to wing bending
Continued on the following page

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LANDING GEAR
A319/A320/A321 GEARS AND DOORS - INTERACTIONS BETWEEN
FLIGHT CREW
OPERATING MANUAL
UNOFFICIAL COPYLANDING GEAR AND AIRCRAFT SYSTEMS
Continued from the previous page
LGCIU 1 LGCIU 2
SYSTEM A/C IN FLT A/C ON GRND
OUTPUT OUTPUT
Blue or green pump
Blue or green pump
BLUE and 1 "FAULT" light not
"FAULT" light inhibited when
GREEN pumps 3 inhibited when related
related pump is stopped(7)
pump is stopped(6)
Runs when electrical Runs when at least
BLUE pump 7
power is available one engine is running
Blue or yellow pump
BLUE and Blue or yellow pump
1 "FAULT" light not
YELLOW "FAULT" light inhibited when
3 inhibited when related
pumps related pump is stopped(8)
pump is stopped(6)
PTU runs if green/yellow
HYD different pressure > 500 PSI
and
• Both MASTER LEVERS
are at OFF or
• Both MASTER LEVERS
PTU runs if
are at ON or
PTU 7 green/yellow different
• Nose wheel steering is
pressure > 500 PSI
not in towing position with
parking brake released.
PTU is inhibited during the
use of the cargo door hand
pump and for 40 s after its
use.
Continued on the following page

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LANDING GEAR
A319/A320/A321 GEARS AND DOORS - INTERACTIONS BETWEEN
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OPERATING MANUAL
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LANDING GEAR AND AIRCRAFT SYSTEMS
Continued from the previous page
LGCIU 1 LGCIU 2
SYSTEM A/C IN FLT A/C ON GRND
OUTPUT OUTPUT
• CAPT, (F/O), ((STBY)) • With engines stopped: no
pitots and CAPT, heating(8)
(F/O) windshields are • With at least one engine
CAPT, (F/O),
heated at high level running:
((STBY))
• All other probes and
probes and 4 4 • CAPT, (F/O), ((STBY))
windows are heated(6)
CAPT, (F/O) (2) (2) pitots and CAPT,
windshields ((8)) ((8)) (F/O) windshields are
and windows heated at low level(8)
heating • All other probes and
ICE RAIN PROT windows are heated
(except TAT probes).

Wing anti ice valves Wing anti ice valves open

WING
3 1 open when the WING for 30 s when the WING
ANTI ICE
ANTI ICE pb is at ON(6) ANTI ICE pb is at ON(8)
RAIN 1 1 Inhibited if engines
Not inhibited(6)
REPELLENT 3 3 are stopped(7)
DRAIN High heating
9 Low heating level is applied
MAST(10) level is applied
L/G SAFETY Safety valve closes if
6 Safety valve opened
VALVE aircraft speed > 260 kt
L/G control 10 10 Retraction not inhibited (9) Retraction inhibited(9)
LANDING GEAR
WHEEL TYRE LO WHEEL TYRE LO
TIRE
5 PR threshold set PR threshold set
PRESS 
to its flight level to its ground level
STANDBY VIBRATION VIBRATION
5
ALTIMETER function active function inhibited
ATC 1(2) available ATC 1(2) inhibited
ATC 1(2) 3 (1)
NAVIGATION in AUTO mode in AUTO mode
No external horn
ADIRU 1(10) 7 when ADIRU supplied External horn not inhibited
from batteries only
Continued on the following page

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LANDING GEAR
A319/A320/A321 GEARS AND DOORS - INTERACTIONS BETWEEN
FLIGHT CREW
OPERATING MANUAL
UNOFFICIAL COPY
LANDING GEAR AND AIRCRAFT SYSTEMS
Continued from the previous page
LGCIU 1 LGCIU 2
SYSTEM A/C IN FLT A/C ON GRND
OUTPUT OUTPUT
On ENG 1(2): (6) On ENG 1(2): (8)
• Reverse inhibited • Reverse available
• No automatic start • Automatic start abort
abort available
1 (1)
• FADEC always • 5 min after eng-shut
3 (3)
supplied down FADEC 1(2) no
8 (8)
POWER PLANT FADEC 1(2) • FLX not available more supplied
• If installed, BUMP not • FLX available
selectable. • If installed, BUMP
selectable.
1 (1) Modulated idle
Modulated idle
3 (3) and approach idle
only available(7)
8 (8) are available(6)
(1) When either LGCIU indicates flight.
(2) When both LGCIU indicate ground.
(3) When either LGCIU indicates ground.
(4) When both LGCIU indicate flight.
(5) Valid from MSN 44.
(6) When either output indicates flight.
(7) When all outputs indicate ground.
(8) When both outputs indicate ground.
(9) One valid output is sufficient.
(10) Valid from MSN 22.

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A319/A320/A321 GEARS AND DOORS - INTERACTIONS BETWEEN
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OPERATING MANUAL
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LANDING GEAR AND AIRCRAFT SYSTEMS

PROXIMITY DETECTORS ON SHOCK ABSORBERS

Ident.: DSC-32-10-30-00018608.0003001 / 17 DEC 24
Applicable to: TC-JLS, TC-JLT, TC-JLU, TC-JLV, TC-JLY, TC-JLZ, TC-JMH, TC-JMI, TC-JMJ, TC-JMK, TC-JML, TC-JPH, TC-JPI,
TC-JPJ, TC-JPK, TC-JPL, TC-JPM, TC-JPN, TC-JPP, TC-JPR, TC-JPS, TC-JPT, TC-JPZ, TC-JRA, TC-JRB, TC-JRC, TC-JRD, TC-JRE,
TC-JRF, TC-JRG, TC-JRH, TC-JRI, TC-JRJ, TC-JRK, TC-JRL, TC-JRM, TC-JRN, TC-JRO, TC-JRP, TC-JRR, TC-JRS, TC-JRT, TC-JRU,
TC-JRV, TC-JRY, TC-JRZ, TC-JSA, TC-JSB, TC-JSC, TC-JSD, TC-JSE, TC-JSF, TC-JSG, TC-JSI, TC-JSJ, TC-JSK, TC-JSL, TC-JSM,
TC-JSN, TC-JSO, TC-JSP, TC-JSR, TC-JSS, TC-JST, TC-JSU, TC-JSV, TC-JSY, TC-JSZ, TC-JTA, TC-JTD, TC-JTE, TC-JTF, TC-JTG,
TC-JTH, TC-JTI, TC-JTJ, TC-JTK, TC-JTL, TC-JTM, TC-JTN, TC-JTO, TC-JTP, TC-JTR, TC-JTV, TC-JTY

1
LGCIU 1 LGCIU 2
SYSTEM A/C IN FLT A/C ON GRND
OUTPUT OUTPUT
STROBE On when
5 Off when AUTO selected
lights AUTO selected
LOGO lights 5 Off when flaps retracted On
AIRSTAIRS
3 1 Control inhibited(1) Control not inhibited(2)
GENERAL 
CARGO Normal control
5 Normal control available
DOOR(5) not available
WATER Preselect water Preselect water
5
FILLING servicing inhibited servicing available
• Skin temperature • Skin temperature < 9 °C
< 32 °C : The : The system is in closed
system is in closed configuration(2)
AVNCS configuration(1) • Skin temperature > 12 °C
5 5
COOLING • Skin temperature > : The system is in open
35 °C : The system configuration(2)
is in intermediate
configuration (1)
GRND
1 1
COOLING Inhibited(1) Not inhibited(2)
AIR COND 
3 3

FWD CARGO Extract fan stopped

5 Extract fan on
VENT when ΔP > 1 PSI
‐ Prepressurization active
before TO (3)
CAB PRESS 5 5 Climb mode active(4)
‐ Depressurization active after
LDG (3)
PACK 1(2)
3 Pack air inlet Pack air inlet flap fully
TEMP
(1) flaps opened closed at TO and LDG
CONTROL
Continued on the following page

THY A319/A320/A321 FLEET DSC-32-10-30 P 8/16

FCOM ←B→ 17 DEC 24
 AIRCRAFT SYSTEMS
LANDING GEAR
A319/A320/A321 GEARS AND DOORS - INTERACTIONS BETWEEN
FLIGHT CREW
OPERATING MANUAL
UNOFFICIAL COPY
LANDING GEAR AND AIRCRAFT SYSTEMS
Continued from the previous page
LGCIU 1 LGCIU 2
SYSTEM A/C IN FLT A/C ON GRND
OUTPUT OUTPUT
‐ In case of oil low pressure,
the automatic shutdown is
In case of oil low press, delayed by :
APU AUTO
APU SHUTDOWN
5 automatic shutdown • 15.5 s if the oil
is delayed by 15.5 s temperature < -4 °C
• 0.05 s if oil temperature
> -4 °C
SERVICE
6 6 Inhibited(6) Available(7)
INTERPHONE
PUBLIC
1 1
ADDRESS PA increased level(6) PA low level(7)
3 3
(PA)
ADIRU and
AVIONICS 1 1 External horn and External horn and
ground 3 3 light inhibited(6) light not inhibited(7)
warning
Communication
FLT Communication with
9 with ground
INTERPHONE ground mechanic available
mechanic inhibited
COCKPIT
9 Inhibited Not inhibited
CALL LIGHT
ACARS
7
COMMUNICATIONS (ACARS MU Available Available
or ATSU)
Runs: (7)
‐ during the first 5 min
1 following energization
1
CVR 3 Runs(6) ‐ with one engine running
3
7
Stops: (7)
5 min after second engine
shutdown
• ERASE function • ERASE function not
inhibited inhibited
• No low frequency • Low frequency signal in
CVR 5
signal in the the loudspeakers if test
loudspeakers if test performed
performed
Continued on the following page

THY A319/A320/A321 FLEET DSC-32-10-30 P 9/16

FCOM ←B→ 17 DEC 24
 AIRCRAFT SYSTEMS
LANDING GEAR
A319/A320/A321 GEARS AND DOORS - INTERACTIONS BETWEEN
FLIGHT CREW
OPERATING MANUAL
UNOFFICIAL COPY
LANDING GEAR AND AIRCRAFT SYSTEMS
Continued from the previous page
LGCIU 1 LGCIU 2
SYSTEM A/C IN FLT A/C ON GRND
OUTPUT OUTPUT
APU start on batteries No APU start delay
DC generation 5
only, is delayed by 45 s when on batteries only
ELEC Main galley not supplied
GALLEY Main galley supplied when
5 when APU GEN
supply APU GEN only is supplying
only is supplying
Display test inhibited
EIS EIS 5 when ANN LT Display test not inhibited
TEST is selected
No APU fire automatic Automatic extinguishing
FIRE APU 5
extinguishing not inhibited
• For SFCC 1(2): • For SFCC 1(2):
Slats alpha/speed Slats alpha/speed lock
lock function active function active if speed >
FLT CTL SFCC 1(2) 5 (5) • For SFCC(2): 60 kt
No flaps movement • For SFCC (2):
inhibition if the cargo Flaps movement inhibition if
door is opened cargo door is opened

Runs: (7)
• During the first 5 min
1 following energization
• DFDR 1
FLT INST • QAR 
3
3
Runs(6) • With one engine running
7
Stops: (7)
5 min after second engine shut
down
FQI uses flight
FQI uses ground
FUEL FQI 5 attitude correction
attitude correction
due to wing bending
Continued on the following page

THY A319/A320/A321 FLEET DSC-32-10-30 P 10/16

FCOM ←B→ 17 DEC 24
 AIRCRAFT SYSTEMS
LANDING GEAR
A319/A320/A321 GEARS AND DOORS - INTERACTIONS BETWEEN
FLIGHT CREW
OPERATING MANUAL
UNOFFICIAL COPYLANDING GEAR AND AIRCRAFT SYSTEMS
Continued from the previous page
LGCIU 1 LGCIU 2
SYSTEM A/C IN FLT A/C ON GRND
OUTPUT OUTPUT
Blue or green pump
BLUE and Blue or green pump
1 "FAULT" light not
GREEN "FAULT" light inhibited when
3 inhibited when related
pumps related pump is stopped(7)
pump is stopped(6)
Runs when electrical Runs when at least
BLUE pump 7
power is available one engine is running
Blue or yellow pump
BLUE and Blue or yellow pump
1 "FAULT" light not
YELLOW "FAULT" light inhibited when
3 inhibited when related
pumps related pump is stopped(8)
pump is stopped(6)
PTU runs if green/yellow
HYD different pressure > 500 PSI
and
• both MASTER LEVERS are
at OFF or
PTU runs if • Both MASTER LEVERS are
PTU 7 green/yellow different at ON or
pressure > 500 PSI • Nose wheel steering is
not in towing position with
parking brake released.
PTU is inhibited during the use
of the cargo door hand pump
and for 40 s after its use.
Continued on the following page

THY A319/A320/A321 FLEET DSC-32-10-30 P 11/16

FCOM ←B→ 17 DEC 24
 AIRCRAFT SYSTEMS
LANDING GEAR
A319/A320/A321 GEARS AND DOORS - INTERACTIONS BETWEEN
FLIGHT CREW
OPERATING MANUAL
UNOFFICIAL COPY
LANDING GEAR AND AIRCRAFT SYSTEMS
Continued from the previous page
LGCIU 1 LGCIU 2
SYSTEM A/C IN FLT A/C ON GRND
OUTPUT OUTPUT
• CAPT, (F/O), • With engines stopped: no
((STBY)) pitots heating(8)
and CAPT, (F/O) • With at least one engine
CAPT, (F/O),
windshields are running:
((STBY))
heated at high level
probes and 4 4 • CAPT, (F/O), ((STBY))
• All other probes and
CAPT, (F/O) (2) (2) pitots and CAPT, (F/O)
windows are heated(6)
windshields ((8)) ((8)) windshields are heated at
and windows low level(8)
heating • All other probes and
ICE RAIN PROT windows are heated
(except TAT probes).

Wing anti ice valves Wing anti ice valves open

WING
3 1 open when the WING for 30 s when the WING
ANTI ICE
ANTI ICE pb is at ON(6) ANTI ICE pb is at ON(8)
RAIN 1 1 Inhibited if engines
Not inhibited(6)
REPELLENT 3 3 are stopped(7)
DRAIN High heating
9 Low heating level is applied
MAST(10) level is applied
L/G SAFETY Safety valve closes if
6 Safety valve opened
VALVE aircraft speed > 260 kt
L/G control 10 10 Retraction not inhibited (9) Retraction inhibited(9)
LANDING GEAR
WHEEL TYRE LO
TIRE WHEEL TYRE LO PR
5 PR threshold set
PRESS  threshold set to its ground level
to its flight level
STANDBY VIBRATION
5 VIBRATION function inhibited
ALTIMETER function active
ATC 1(2) available ATC 1(2) inhibited
ATC 1(2) 3 (1)
NAVIGATION in AUTO mode in AUTO mode
No external horn
ADIRU 1(10) 7 when ADIRU supplied External horn not inhibited
from batteries only
Continued on the following page

THY A319/A320/A321 FLEET DSC-32-10-30 P 12/16

FCOM ←B→ 17 DEC 24
 AIRCRAFT SYSTEMS
LANDING GEAR
A319/A320/A321 GEARS AND DOORS - INTERACTIONS BETWEEN
FLIGHT CREW
OPERATING MANUAL
UNOFFICIAL COPY LANDING GEAR AND AIRCRAFT SYSTEMS
Continued from the previous page
LGCIU 1 LGCIU 2
SYSTEM A/C IN FLT A/C ON GRND
OUTPUT OUTPUT
On ENG 1(2): (6) On ENG 1(2): (8)
• Reverse inhibited • Reverse available
• No automatic start • Automatic start abort
abort available
1 (1)
• FADEC always • 5 min after eng-shut down
3 (3)
supplied FADEC 1(2) no more
8 (8)
POWER PLANT FADEC 1(2) • FLX not available supplied
• If installed, BUMP not • FLX available
selectable. • If installed, BUMP
selectable.
1 (1) Modulated idle
3 (3) and approach idle Modulated idle only available (7)
8 (8) are available(6)
(1) When either LGCIU indicates flight.
(2) When both LGCIU indicate ground.
(3) When either LGCIU indicates ground.
(4) When both LGCIU indicate flight.
(5) Valid from MSN 44.
(6) When either output indicates flight.
(7) When all outputs indicate ground.
(8) When both outputs indicate ground.
(9) One valid output is sufficient.
(10) Valid from MSN 22.

THY A319/A320/A321 FLEET DSC-32-10-30 P 13/16

FCOM ←B 17 DEC 24
 AIRCRAFT SYSTEMS
LANDING GEAR
A319/A320/A321 GEARS AND DOORS - INTERACTIONS BETWEEN
FLIGHT CREW
OPERATING MANUAL
UNOFFICIAL COPY
LANDING GEAR AND AIRCRAFT SYSTEMS

PROXIMITY DETECTORS ON UPLOCKS

Ident.: DSC-32-10-30-00018610.0002001 / 21 MAR 16
Applicable to: ALL

LGCIU 1 LGCIU 2
SYSTEM L/G UPLOCKED L/G NOT UPLOCKED
OUTPUT OUTPUT
If UP selected :(1) If UP selected :(1)
L/G control 19 19
L/G doors will close L/G doors will not close
16 16 If UP selected :(2) If UP selected :(2)
ECAM
17 17 L/G uplocked indications L/G in transit indications
LANDING GEAR WHEEL page
18 18
16 If UP selected :(2) If UP selected :(2)
L/G indicator
17 no indication "UNLK" red indications
panel
18
(1) One valid output is sufficient.
(2) When all outputs indicate the same position.

PROXIMITY DETECTORS ON DOORS

Ident.: DSC-32-10-30-00018611.0001001 / 21 MAR 16
Applicable to: ALL

LGCIU 1 LGCIU 2
SYSTEM DOORS FULLY OPENED DOORS CLOSED
OUTPUT OUTPUT
L/G extension or retraction L/G extension or retraction
L/G control 24 24
possible (1) inhibited (1)
20 20 Doors fully opened Doors closed indication
LANDING GEAR
ECAM 21 21 indication
WHEEL page 22 22
23 23
(1) One valid output is sufficient.

PROXIMITY DETECTORS ON DOWNLOCKS

Ident.: DSC-32-10-30-00018613.0001001 / 21 MAR 16
Applicable to: ALL

LGCIU 1 LGCIU 2
SYSTEM L/G DOWNLOCKED L/G NOT DOWNLOCKED
OUTPUT OUTPUT
TAXI/T.O
GEN lights
15 Lights not inhibited Lights inhibited
"NO SMOKING" and (1) "NO SMOKING" (1)and
COMM SIGNS 12 12 "EXIT" signs on when EXIT" signs inhibited
AUTO selected(2) when AUTO selected(3)
Continued on the following page

THY A319/A320/A321 FLEET DSC-32-10-30 P 14/16

FCOM C to E → 17 DEC 24
 AIRCRAFT SYSTEMS
LANDING GEAR
A319/A320/A321 GEARS AND DOORS - INTERACTIONS BETWEEN
FLIGHT CREW
OPERATING MANUAL
UNOFFICIAL COPY LANDING GEAR AND AIRCRAFT SYSTEMS
Continued from the previous page
LGCIU 1 LGCIU 2
SYSTEM L/G DOWNLOCKED L/G NOT DOWNLOCKED
OUTPUT OUTPUT
FLT INST WBS  15 15 Active
(4) Inhibited (5)
VLE indication
FMGS FAC 1(2) 12 12
displayed on PFD 1(2)
No VLE indication
If DOWN selected : (6) If DOWN selected : (6)
L/G control 14 14
L/G doors will close L/G doors will not close
ECAM 11 11 If DOWN selected : (7) If DOWN selected : (7)
WHEEL 13 13 L/G down indications L/G in transit indications
page 15 15
11 If DOWN selected :(7) If DOWN selected : (7)
L/G INDIC
LANDING GEAR panel
13 L/G down indications L/G in transit indications
15
BRAKING
15 15 BSCU test operative(2) BSCU test inhibited(3)
STEERING
BRAKE
Cooling available Cooling inhibited
COOLING 13
when ON selected when ON selected
FANS 
"TOO LOW-FLAPS" or "TOO LOW-GEAR" or
NAV GPWS 13 "TOO LOW TERRAIN" "TOO LOW TERRAIN"
warning operative warning operative
(1) For cabin not configured for non smoking flight
(2) When either output indicates DOWNLOCK.
(3) When both outputs indicate NOT DOWNLOCK.
(4) When both outputs indicate DOWNLOCK.
(5) When either output indicates NOT DOWNLOCK.
(6) One valid output is sufficient.
(7) When all outputs indicate the same position.

THY A319/A320/A321 FLEET DSC-32-10-30 P 15/16

FCOM ←E 17 DEC 24
 AIRCRAFT SYSTEMS
LANDING GEAR
A319/A320/A321 GEARS AND DOORS - INTERACTIONS BETWEEN
FLIGHT CREW
OPERATING MANUAL
UNOFFICIAL COPY
LANDING GEAR AND AIRCRAFT SYSTEMS

PROXIMITY DETECTORS ON CARGO DOORS

Ident.: DSC-32-10-30-00018614.0001001 / 06 JUN 22
Applicable to: ALL

LOCKING HANDLE OR SHAFT, DOOR SILLS

LGCIU 1 LGCIU 2
SYSTEM LOCKED UNLOCKED
OUTPUT OUTPUT
Forward (aft) door symbol
ECAM 30 Forward (aft) door
appears amber, associated
DOOR PAGE (31) symbol appears green
with "CARGO" amber
CRG DOORS 34 Forward (aft) door Forward (aft) door
CARGO (35) normal opening inhibition normal opening possible
DOOR
36  Forward (aft) door normal Forward (aft) door normal
OPERATION
(37)  operation possible operation inhibited

MANUAL SELECTOR VALVE

LGCIU 1 LGCIU 2
SYSTEM CLOSE OPEN
OUTPUT OUTPUT
CARGO
32 Forward (aft) door Forward (aft) door
CRG DOORS DOOR
(33) normal opening inhibition normal opening possible
OPERATION

PROXIMITY DETECTORS ON FLAPS ATTACHMENTS

Ident.: DSC-32-10-30-00001291.0001001 / 22 MAR 16
Applicable to: ALL

LGCIU 1 LGCIU 2 FLAP ATTACHMENT

SYSTEM FLAP ATTACHMENT
OUTPUT OUTPUT FAILURE
28 28 L(R) FLAPS "FLAPS LOCKED”
FLT CTL SFCC
(29) (29) normal operation (1) warning (2)
(1) When at least one SFCC detects normal operation
(2) When both SFCCs detect attachment failure

THY A319/A320/A321 FLEET DSC-32-10-30 P 16/16

FCOM F to G 17 DEC 24
 AIRCRAFT SYSTEMS
LANDING GEAR
A319/A320/A321
FLIGHT CREW
OPERATING MANUAL
UNOFFICIAL COPY GEARS AND DOORS - CONTROLS AND INDICATORS

LANDING GEAR INDICATOR PANEL

Ident.: DSC-32-10-40-00018615.0001001 / 21 MAR 16
Applicable to: ALL

This panel is connected to LGCIU1, which receives signals from proximity detectors.
▿ light: comes on green if the gear is locked down.
UNLK: comes on red if the gear is not locked in the selected position.
light
Note: This panel is connected to the LGCIU1 only, therefore, the lights on the LDG GEAR
indicator panel come on as long as the LGCIU1 is electrically supplied.
If one UNLK indication remains on, the landing gear position can be confirmed using the
WHEEL SD page (information from LGCIU 1 & 2). Only one green triangle on each landing
gear is sufficient to confirm that the landing gear is downlocked.

LANDING GEAR SELECTOR LEVER

Ident.: DSC-32-10-40-00018616.0001001 / 20 MAY 16
Applicable to: ALL

A two-position selector lever sends electrical signals to the two LGCIUs. These control the green
hydraulic supply to the landing gear system by means of selector valves.
The flight crew must always move the L/G lever in one continuous movement (i.e. with no stop
between both positions).
When the flight crew selects UP or DOWN (and if the airspeed is below 260 kt):
‐ All landing gear doors open
‐ Each landing gear moves to the selected position
‐ All landing gear doors close.

THY A319/A320/A321 FLEET DSC-32-10-40 P 1/6

FCOM A to B → 12 AUG 24
 AIRCRAFT SYSTEMS
LANDING GEAR
A319/A320/A321
FLIGHT CREW
OPERATING MANUAL
UNOFFICIAL COPY
GEARS AND DOORS - CONTROLS AND INDICATORS

(1) L/G LEVER

UP : This position selects landing gear retraction.
While the landing gear doors are opening, the normal brake system brakes the
wheels of the main landing gear automatically.
A brake band in the nose landing gear well brakes the nose landing gear wheels as
the doors close (for aircraft equipped with nose landing gear rubbing strips).
DOWN : This position selects landing gear extension.
An interlock mechanism prevents anyone from accidentally retracting the gear
while the aircraft is on the ground. It does so by locking the lever in DOWN position
when the shock absorber on either main gear is compressed (aircraft on ground) or
the nose wheel steering is not centered.
The landing gear hydraulic system remains pressurized as long as the landing gear
is extended (if green hydraulic pressure is available).
(2) RED ARROW
This red arrow lights up if the landing gear is not locked down when the aircraft is in the landing
configuration, and a red warning appears on ECAM.

THY A319/A320/A321 FLEET DSC-32-10-40 P 2/6

FCOM ←B 12 AUG 24
 AIRCRAFT SYSTEMS
LANDING GEAR
A319/A320/A321
FLIGHT CREW
OPERATING MANUAL
UNOFFICIAL COPY GEARS AND DOORS - CONTROLS AND INDICATORS

LANDING GEAR GRAVITY EXTENSION

Ident.: DSC-32-10-40-00018617.0001001 / 21 MAR 16
Applicable to: ALL

To put the landing gear down by gravity, the flight crew must pull the gear crank out, then turn it
clockwise for 3 turns.
When the flight crew operates the crank handle, the cutout valve shuts off hydraulic pressure to the
landing gear system and depressurizes it.

THY A319/A320/A321 FLEET DSC-32-10-40 P 3/6

FCOM C 12 AUG 24
 AIRCRAFT SYSTEMS
LANDING GEAR
A319/A320/A321
FLIGHT CREW
OPERATING MANUAL
UNOFFICIAL COPY
GEARS AND DOORS - CONTROLS AND INDICATORS

WHEEL SD PAGE
Ident.: DSC-32-10-40-00018618.0007001 / 28 NOV 23
Applicable to: ALL

Wheel SD Page

L/G CTL INDICATION

The associated landing gear position disagrees with the
lever position following a 30 s time delay.
The associated ECAM alert is triggered.
UPLOCK INDICATION
The associated landing gear is locked down, and one or
more uplocks are in the closed position.
Associated with the following ECAM alert: L/G GEAR
UPLOCK FAULT(Refer to PRO-ABN-LG L/G GEAR
UPLOCK FAULT).
LANDING GEAR INDICATION
The landing gear is indicated by two triangles for each gear.
The left triangle is controlled by LGCIU 1, the right one by LGCIU 2.

THY A319/A320/A321 FLEET DSC-32-10-40 P 4/6

FCOM D→ 12 AUG 24
 AIRCRAFT SYSTEMS
LANDING GEAR
A319/A320/A321
FLIGHT CREW
OPERATING MANUAL
UNOFFICIAL COPY GEARS AND DOORS - CONTROLS AND INDICATORS

The LGCIU detects the associated landing gear as locked

down.

The LGCIU detects the associated landing gear as in

transit.

The LGCIU detects the associated landing gear as

retracted and uplocked.

The LGCIU is failed.

Note: When the landing gear lever is down, one LGCIU locked down indication (one green
triangle per gear) is sufficient to indicate that the landing gear is down and locked.
LANDING GEAR DOOR INDICATION
The associated landing gear door is closed and uplocked.

The associated landing gear door is in transit.

The associated landing gear door is open.

MEMO DISPLAY
Ident.: DSC-32-10-40-00018778.0001001 / 06 JUN 22
Applicable to: ALL

FLT L/G DOWN : This memo appears in green if the aircraft is operated in "flight with landing
gear down" configuration.

THY A319/A320/A321 FLEET DSC-32-10-40 P 5/6

FCOM ← D to E 12 AUG 24
 AIRCRAFT SYSTEMS
LANDING GEAR
A319/A320/A321
FLIGHT CREW
OPERATING MANUAL
UNOFFICIAL COPY
GEARS AND DOORS - CONTROLS AND INDICATORS

Intentionally left blank

THY A319/A320/A321 FLEET DSC-32-10-40 P 6/6

FCOM 12 AUG 24
 AIRCRAFT SYSTEMS
LANDING GEAR
A319/A320/A321
FLIGHT CREW
OPERATING MANUAL
UNOFFICIAL COPY NOSE WHEEL STEERING - DESCRIPTION

DESCRIPTION
Ident.: DSC-32-20-10-00018619.0007001 / 28 FEB 18
Applicable to: ALL

A hydraulic actuating cylinder steers the nose wheel. The yellow hydraulic system supplies pressure
to the cylinder, and electric signals from the Brake and Steering Control Unit (BSCU) control it.
The BSCU receives orders from:
‐ Captain's, and the First Officer’s steering hand wheels (orders added algebraically), or
‐ Rudder pedals, or
‐ Autopilot.
The BSCU transforms these orders into nose wheel steering angle. That angle has the following
limits, which depend on ground speed and the origin of the orders.

The steering system receives actuating hydraulic pressure when:

‐ A/SKID & N/W STRG switch is ON
‐ Towing control lever is in normal position
‐ At least one engine is running
‐ Aircraft is on ground.
The handwheel can turn the nosewheel up to 75 ° in either direction. A lever, on the towing electrical
box (on nose landing gear), enables ground crew to deactivate the steering system for towing. Then
the wheel can be turned 95 ° in either direction.
To prevent rudder pedal orders, or autopilot orders, from going to the BSCU, the pilots can use the
pushbutton on either steering handwheel.
An internal cam mechanism returns the nose wheel to the centered position after takeoff.

THY A319/A320/A321 FLEET DSC-32-20-10 P 1/4

FCOM A 12 AUG 24
 AIRCRAFT SYSTEMS
LANDING GEAR
A319/A320/A321
FLIGHT CREW
OPERATING MANUAL
UNOFFICIAL COPY
NOSE WHEEL STEERING - DESCRIPTION

ARCHITECTURE
Ident.: DSC-32-20-10-00001298.0002001 / 21 MAR 16

THY A319/A320/A321 FLEET DSC-32-20-10 P 2/4

FCOM B→ 12 AUG 24
 AIRCRAFT SYSTEMS
LANDING GEAR
A319/A320/A321
FLIGHT CREW
OPERATING MANUAL
UNOFFICIAL COPY
NOSE WHEEL STEERING - DESCRIPTION

Applicable to: ALL

THY A319/A320/A321 FLEET DSC-32-20-10 P 3/4

FCOM ←B 12 AUG 24
 AIRCRAFT SYSTEMS
LANDING GEAR
A319/A320/A321
FLIGHT CREW
OPERATING MANUAL
UNOFFICIAL COPY
NOSE WHEEL STEERING - DESCRIPTION

Intentionally left blank

THY A319/A320/A321 FLEET DSC-32-20-10 P 4/4

FCOM 12 AUG 24
 AIRCRAFT SYSTEMS
LANDING GEAR
A319/A320/A321
FLIGHT CREW
OPERATING MANUAL
UNOFFICIAL COPY
NOSE WHEEL STEERING - CONTROLS AND INDICATORS

SIDE CONSOLES
Ident.: DSC-32-20-20-00018620.0001001 / 28 NOV 23
Applicable to: ALL

SIDE CONSOLES

STEERING HANDWHEELS
The steering handwheels, that are interconnected, can steer the nose wheel up to 75 ° in either
direction.
Note: The steering system centers the nose wheel automatically after liftoff.

THY A319/A320/A321 FLEET DSC-32-20-20 P 1/4

FCOM A→ 28 NOV 23
 AIRCRAFT SYSTEMS
LANDING GEAR
A319/A320/A321
FLIGHT CREW
OPERATING MANUAL
UNOFFICIAL COPY
NOSE WHEEL STEERING - CONTROLS AND INDICATORS

RUDDER PEDAL DISC pb

Pressing this button on either handwheel removes control of nose wheel steering from the rudder
pedals until the button is released.

WHEEL SD PAGE
Ident.: DSC-32-20-20-00018622.0004001 / 21 MAR 16
Applicable to: ALL

(1) N/W STEERING indication

It appears in amber, when nosewheel steering is lost, due to failure of the nosewheel steering
system, or of both BSCU channels, or in case of a yellow hydraulic system low pressure, or if
the A/SKID & N/W STRG switch is OFF.
(2) N/W STEERING hydraulic supply indication:
Only when the N/W STEERING indication is displayed, Y is displayed:
‐ In green when the yellow hydraulic system is not failed, or
‐ In amber when the yellow hydraulic system low pressure.

THY A319/A320/A321 FLEET DSC-32-20-20 P 2/4

FCOM ← A to B 28 NOV 23
 AIRCRAFT SYSTEMS
LANDING GEAR
A319/A320/A321
FLIGHT CREW
OPERATING MANUAL
UNOFFICIAL COPY
NOSE WHEEL STEERING - CONTROLS AND INDICATORS

MEMO DISPLAY
Ident.: DSC-32-20-20-00016853.0001001 / 04 JUN 19
Applicable to: ALL

NW STRG DISC : This memo appears, when the nose wheel steering selector is in the towing
position and with engines not running.
NW STRG DISC : This memo appears, when the nose wheel steering selector is in the towing
position and if at least one engine is running.

THY A319/A320/A321 FLEET DSC-32-20-20 P 3/4

FCOM C 28 NOV 23
 AIRCRAFT SYSTEMS
LANDING GEAR
A319/A320/A321
FLIGHT CREW
OPERATING MANUAL
UNOFFICIAL COPY
NOSE WHEEL STEERING - CONTROLS AND INDICATORS

Intentionally left blank

THY A319/A320/A321 FLEET DSC-32-20-20 P 4/4

FCOM 28 NOV 23
 AIRCRAFT SYSTEMS
LANDING GEAR
A319/A320/A321
FLIGHT CREW
OPERATING MANUAL
UNOFFICIAL COPY BRAKES AND ANTISKID - DESCRIPTION

GENERAL
Ident.: DSC-32-30-10-00018623.0002001 / 21 MAR 16
Applicable to: ALL

The main wheels are equipped with carbon multidisc brakes, which can be actuated by either of two
independent brake systems.
The normal system uses green hydraulic pressure, whereas the alternate system uses the yellow
hydraulic system backed up by the hydraulic accumulator.
An anti-skid and autobrake system is also provided.
Braking commands come from either the brake pedals (pilot action), or the autobrake system
(deceleration rate selected by the crew).
In normal operation, a dual channel Brake and Steering Control Unit (BSCU) controls normal braking
and antiskid.
Depending on the failure, braking may revert to:
‐ Alternate braking with antiskid. This braking mode is controlled by the Alternate Braking Control
Unit (ABCU), and the antiskid is controlled by the BSCU
‐ Alternate braking without antiskid. This braking mode is fully-controlled by the ABCU
‐ Alternate braking without antiskid on accumulator. This braking mode is fully-controlled by the
ABCU.
All the normal and alternate braking components are fully-monitored. Any detected failure is signaled
to the crew via ECAM warnings.
The BSCU performs the following secondary functions:
‐ Checks the residual pressure in the brakes
‐ Monitors the brake temperature
‐ Provides discrete wheel speed information to other aircraft systems.
A changeover between the two BSCU channels takes place at each DOWN landing gear lever
selection, or in case one channel fails.
The main gear wheels are fitted with fusible plugs which protect against tire burst, in the event of
overheat.
Main gear wheels are also equipped with brake cooling fans  , which permit a high speed cooling
of brakes.

ANTI-SKID SYSTEM
Ident.: DSC-32-30-10-00018624.0001001 / 21 MAR 16
Applicable to: ALL

The antiskid system provides maximum braking efficiency by maintaining the wheels at the limit of an
impending skid.

THY A319/A320/A321 FLEET DSC-32-30-10 P 1/8

FCOM A to B → 17 DEC 24
 AIRCRAFT SYSTEMS
LANDING GEAR
A319/A320/A321
FLIGHT CREW
OPERATING MANUAL
UNOFFICIAL COPY
BRAKES AND ANTISKID - DESCRIPTION

At skid onset, brake release orders are sent to the normal and alternate servovalves, as well as to
the ECAM system which displays the released brakes.
Without using autobrake, full braking performance is achieved only with brake pedals at full
deflection.
The antiskid system is deactivated below 20 kt (ground speed).
An ON/OFF switch activates, or deactivates, the antiskid and nosewheel steering systems.
PRINCIPLE
The speed of each main gear wheel (given by a tachometer) is compared to the aircraft speed
(reference speed). When the speed of a wheel decreases below approximately 0.87 times
(depending on conditions) reference speed, brake release orders are given to maintain the wheel
slip at that value (best braking efficiency).
In normal operation, the reference speed is determined by the BSCU from the horizontal
acceleration of ADIRU 1, or ADIRU 2, or ADIRU 3.
In case all ADIRUs fail, reference speed equals the maximum of either main landing gear wheel
speeds.

AUTO BRAKE
Ident.: DSC-32-30-10-A-00018625.0001001 / 21 MAR 16
Applicable to: ALL

GENERAL
The purposes of the autobrake system are the following:
‐ Reduce the braking distance in case of an aborted takeoff
‐ Establish and maintain a selected deceleration rate during landing, thereby improving
passenger comfort and reducing crew workload.

AUTO BRAKE - SYSTEM ARMING

Ident.: DSC-32-30-10-A-00018626.0002001 / 21 MAR 16
Applicable to: TC-JPH, TC-JPJ, TC-JPS, TC-JTS, TC-JTT, TC-JTU, TC-LBC, TC-LBD

SYSTEM ARMING
The crew may arm the system by pressing the LO, MED, or MAX pushbutton provided all the
following arming conditions are met :
‐ Green pressure available
‐ Anti-skid electrically-powered

THY A319/A320/A321 FLEET DSC-32-30-10 P 2/8

FCOM ← B to C → 17 DEC 24
 AIRCRAFT SYSTEMS
LANDING GEAR
A319/A320/A321
FLIGHT CREW
OPERATING MANUAL
UNOFFICIAL COPY BRAKES AND ANTISKID - DESCRIPTION

‐ No failure in the braking system

‐ At least one ADIRU is available.
Note: 1. Auto brake may be armed with the parking brake on.
2. MAX autobrake mode cannot be armed in flight.

Ident.: DSC-32-30-10-A-00018626.0003001 / 09 NOV 17

1 Applicable to: TC-JLS, TC-JLT, TC-JLU, TC-JLV, TC-JLY, TC-JLZ, TC-JMH, TC-JMI, TC-JMJ, TC-JMK, TC-JML, TC-JPI, TC-JPK,
TC-JPL, TC-JPM, TC-JPN, TC-JPP, TC-JPR, TC-JPT, TC-JPZ, TC-JRA, TC-JRB, TC-JRC, TC-JRD, TC-JRE, TC-JRF, TC-JRG, TC-JRH,
TC-JRI, TC-JRJ, TC-JRK, TC-JRL, TC-JRM, TC-JRN, TC-JRO, TC-JRP, TC-JRR, TC-JRS, TC-JRT, TC-JRU, TC-JRV, TC-JRY, TC-JRZ,
TC-JSA, TC-JSB, TC-JSC, TC-JSD, TC-JSE, TC-JSF, TC-JSG, TC-JSI, TC-JSJ, TC-JSK, TC-JSL, TC-JSM, TC-JSN, TC-JSO, TC-JSP,
TC-JSR, TC-JSS, TC-JST, TC-JSU, TC-JSV, TC-JSY, TC-JSZ, TC-JTA, TC-JTD, TC-JTE, TC-JTF, TC-JTG, TC-JTH, TC-JTI, TC-JTJ,
TC-JTK, TC-JTL, TC-JTM, TC-JTN, TC-JTO, TC-JTP, TC-JTR, TC-JTV, TC-JTY, TC-LBA, TC-LBB, TC-LBF, TC-LBG, TC-LBH, TC-LBJ,
TC-LBK, TC-LPA, TC-LPB, TC-LPC, TC-LPD, TC-LPE, TC-LPF, TC-LPG, TC-LPH, TC-LPI, TC-LPJ, TC-LPK, TC-LPL, TC-LPM, TC-LPN,
TC-LPO, TC-LPP, TC-LPR, TC-LSA, TC-LSB, TC-LSC, TC-LSD, TC-LSE, TC-LSF, TC-LSG, TC-LSH, TC-LSJ, TC-LSK, TC-LSL, TC-LSM,
TC-LSN, TC-LSO, TC-LSP, TC-LSR, TC-LSS, TC-LST, TC-LSU, TC-LSV, TC-LSY, TC-LSZ, TC-LTA, TC-LTB, TC-LTC, TC-LTD, TC-LTE,
TC-LTF, TC-LTG, TC-LTH, TC-LTI, TC-LTJ, TC-LTK, TC-LTL, TC-LTM, TC-LTN, TC-LTO, TC-LTP, TC-LTR, TC-LTS, TC-LTT, TC-LTU,
TC-LTV, TC-LTY, TC-LTZ, TC-LUA, TC-LUB, TC-LUC, TC-LUE, TC-LUI, TC-LUJ, TC-LUK, TC-LUL, TC-LUM, TC-LUN, TC-LUO, TC-LUP,
TC-LUR, TC-LUS, TC-LUU, TC-LUV, TC-LUY, TC-LUZ, TLBI

SYSTEM ARMING
The crew may arm the system by pressing the LO, MED, or MAX pushbutton provided all the
following arming conditions are met:
‐ Green pressure available
‐ Anti-skid electrically-powered
‐ No failure in the braking system
‐ At least one ADIRU is available.
Note: 1. Auto brake may be armed with the parking brake on.
2. MAX autobrake mode cannot be armed in flight.

The armed AUTO BRK mode is displayed in blue on the Flight Mode Annunciator (FMA).

AUTO BRAKE - SYSTEM ACTIVATION

Ident.: DSC-32-30-10-A-00018627.0002001 / 17 OCT 17
Applicable to: TC-JPH, TC-JPJ, TC-JPS, TC-JTS, TC-JTT, TC-JTU, TC-LBC, TC-LBD

SYSTEM ACTIVATION
Automatic braking is activated when:
‐ The command for ground spoilers extension is detected (Refer to DSC-27-10-20 Speed Brakes
and Ground Spoilers - Speed Brake Control), for LO and MED mode, or
‐ The command for ground spoilers extension is detected, and the wheel speed is above 40 kt,
for MAX mode.

THY A319/A320/A321 FLEET DSC-32-30-10 P 3/8

FCOM ←C→ 17 DEC 24
 AIRCRAFT SYSTEMS
LANDING GEAR
A319/A320/A321
FLIGHT CREW
OPERATING MANUAL
UNOFFICIAL COPY
BRAKES AND ANTISKID - DESCRIPTION

Therefore, if the aircraft makes an acceleration stop and begins to decelerate when the wheel
speed is under 72 kt, the automatic braking will not activate because the ground spoilers will not
extend.
For autobrake to activate, at least two SEC’s must be operative.
Ident.: DSC-32-30-10-A-00018627.0003001 / 09 NOV 17
2 Applicable to: TC-JLS, TC-JLT, TC-JLU, TC-JLV, TC-JLY, TC-JLZ, TC-JMH, TC-JMI, TC-JMJ, TC-JMK, TC-JML, TC-JPI, TC-JPK,
TC-JPL, TC-JPM, TC-JPN, TC-JPP, TC-JPR, TC-JPT, TC-JPZ, TC-JRA, TC-JRB, TC-JRC, TC-JRD, TC-JRE, TC-JRF, TC-JRG, TC-JRH,
TC-JRI, TC-JRJ, TC-JRK, TC-JRL, TC-JRM, TC-JRN, TC-JRO, TC-JRP, TC-JRR, TC-JRS, TC-JRT, TC-JRU, TC-JRV, TC-JRY, TC-JRZ,
TC-JSA, TC-JSB, TC-JSC, TC-JSD, TC-JSE, TC-JSF, TC-JSG, TC-JSI, TC-JSJ, TC-JSK, TC-JSL, TC-JSM, TC-JSN, TC-JSO, TC-JSP,
TC-JSR, TC-JSS, TC-JST, TC-JSU, TC-JSV, TC-JSY, TC-JSZ, TC-JTA, TC-JTD, TC-JTE, TC-JTF, TC-JTG, TC-JTH, TC-JTI, TC-JTJ,
TC-JTK, TC-JTL, TC-JTM, TC-JTN, TC-JTO, TC-JTP, TC-JTR, TC-JTV, TC-JTY, TC-LBA, TC-LBB, TC-LBF, TC-LBG, TC-LBH, TC-LBJ,
TC-LBK, TC-LPA, TC-LPB, TC-LPC, TC-LPD, TC-LPE, TC-LPF, TC-LPG, TC-LPH, TC-LPI, TC-LPJ, TC-LPK, TC-LPL, TC-LPM, TC-LPN,
TC-LPO, TC-LPP, TC-LPR, TC-LSA, TC-LSB, TC-LSC, TC-LSD, TC-LSE, TC-LSF, TC-LSG, TC-LSH, TC-LSJ, TC-LSK, TC-LSL, TC-LSM,
TC-LSN, TC-LSO, TC-LSP, TC-LSR, TC-LSS, TC-LST, TC-LSU, TC-LSV, TC-LSY, TC-LSZ, TC-LTA, TC-LTB, TC-LTC, TC-LTD, TC-LTE,
TC-LTF, TC-LTG, TC-LTH, TC-LTI, TC-LTJ, TC-LTK, TC-LTL, TC-LTM, TC-LTN, TC-LTO, TC-LTP, TC-LTR, TC-LTS, TC-LTT, TC-LTU,
TC-LTV, TC-LTY, TC-LTZ, TC-LUA, TC-LUB, TC-LUC, TC-LUE, TC-LUI, TC-LUJ, TC-LUK, TC-LUL, TC-LUM, TC-LUN, TC-LUO, TC-LUP,
TC-LUR, TC-LUS, TC-LUU, TC-LUV, TC-LUY, TC-LUZ, TLBI

SYSTEM ACTIVATION
Automatic braking is activated when:
‐ The command for ground spoilers extension is detected (Refer to DSC-27-10-20 Speed Brakes
and Ground Spoilers - Speed Brake Control), for LO and MED mode, or
‐ The command for ground spoilers extension is detected, and the wheel speed is above 40 kt,
for MAX mode.
Therefore, if the aircraft makes an acceleration stop and begins to decelerate when the wheel
speed is under 72 kt, the automatic braking will not activate because the ground spoilers will not
extend.
For autobrake to activate, at least two SEC’s must be operative.
The active AUTO BRK mode is displayed in green on the Flight Mode Annunciator (FMA).

Ident.: DSC-32-30-10-A-00018628.0001001 / 21 MAR 16

Applicable to: ALL

SYSTEM DEACTIVATION
The system deactivates when:
‐ The system disarmed (Refer to DSC-32-30-10 Auto Brake - System Disarming), or
‐ The ground spoilers retract. In this case it remains armed.

THY A319/A320/A321 FLEET DSC-32-30-10 P 4/8

FCOM ←C→ 17 DEC 24
 AIRCRAFT SYSTEMS
LANDING GEAR
A319/A320/A321
FLIGHT CREW
OPERATING MANUAL
UNOFFICIAL COPY BRAKES AND ANTISKID - DESCRIPTION

Ident.: DSC-32-30-10-A-00018629.0002001 / 09 NOV 17

Applicable to: ALL

SYSTEM DISARMING
The system disarms when:
‐ Flight crew presses the pushbutton switch, or
‐ One or more arming conditions is lost, or
‐ After take-off/touch and go, or
‐ Flight crew applies enough deflection to at least one brake pedal when autobrake is active in
MAX, MED or LO mode.

BRAKING MODES
Applicable to: ALL
Ident.: DSC-32-30-10-B-00018630.0001001 / 21 MAR 16

GENERAL
There are four modes of operation:
‐ Normal braking
‐ Alternate braking with antiskid
‐ Alternate braking without antiskid
‐ Parking brake.
Ident.: DSC-32-30-10-B-00018631.0001001 / 21 MAR 16

NORMAL BRAKING
Normal braking is operative when:
‐ Green hydraulic pressure is available
‐ A/SKID & N/W STRG switch is ON.
During normal braking, antiskid is operative and autobrake is available.
Braking is electrically-controlled through the BSCU from:
‐ Pilot’s pedals, or
‐ Automatically activates when:
• On ground by the autobrake system, or
• In flight when the landing gear lever is up.
The antiskid system is controlled by the BSCU via the normal servo valves.
There is no brake pressure indication in the cockpit.

THY A319/A320/A321 FLEET DSC-32-30-10 P 5/8

FCOM ← C to D → 17 DEC 24
 AIRCRAFT SYSTEMS
LANDING GEAR
A319/A320/A321
FLIGHT CREW
OPERATING MANUAL
UNOFFICIAL COPY
BRAKES AND ANTISKID - DESCRIPTION

Ident.: DSC-32-30-10-B-00018632.0002001 / 13 JUN 24

ALTERNATE BRAKING WITH ANTI-SKID

Autobrake is inoperative.
Braking uses this mode when green hydraulic pressure is insufficient, and :
‐ Yellow hydraulic pressure is available
‐ A/SKID & N/W STRG switch is ON
‐ Parking brake is not ON.
Braking inputs are made by the brake pedals and sent to the ABCU. Then, taking into account the
brake pedal input, the ABCU:
‐ Energizes the alternate brake selector valve to pressurize the yellow hydraulic circuit
‐ Electrically controls the Alternate Servo Valve to obtain the correct pressure for the related
brakes.
Antiskid is controlled by the BSCU.
A triple indicator on the center instrument panel indicates the pressure delivered to the left and
right brakes, as well as the accumulator pressure.
Ident.: DSC-32-30-10-B-00018633.0002001 / 13 JUN 24

ALTERNATE BRAKING WITHOUT ANTI-SKID

Autobrake and antiskid are inoperative.
The antiskid system is either deactivated:
‐ Electrically (A/SKID & N/W STRG sw OFF, or power supply failure, or BSCU failure), or
‐ Hydraulically (Y + G system low pressure, the brakes are supplied by the brake accumulator
only).
Depending on the brake pedals’ demand, the ABCU controls the alternate brake selector and the
alternate servovalves.
Brake pressure and accumulator pressure are indicated on a triple indicator, located on the
center instrument panel. To avoid wheel locking and limit the risk of tire burst, brake pressure is
automatically limited to 1 000 PSI.
The accumulator can supply at least 7 full brake applications.
Ident.: DSC-32-30-10-B-00018634.0002001 / 21 MAR 16

PARKING BRAKE
Brakes are supplied by the yellow hydraulic system, or by accumulator pressure via the parking
brake control valve, which opens allowing full pressure application on the main gear wheel brakes.
The accumulator maintains the parking pressure for at least 12 h.
If the parking brake is activated and no yellow hydraulic or accumulator brake pressure is
available, then the normal braking system can be applied via the brake pedals.

THY A319/A320/A321 FLEET DSC-32-30-10 P 6/8

FCOM ←D→ 17 DEC 24
 AIRCRAFT SYSTEMS
LANDING GEAR
A319/A320/A321
FLIGHT CREW
OPERATING MANUAL
UNOFFICIAL COPY BRAKES AND ANTISKID - DESCRIPTION

Yellow accumulators can be pressurized by pressing the yellow electrical pump switch.
A triple indicator on the center instrument panel indicates the pressure delivered to the left and
right brakes, as well as the accumulator pressure.

THY A319/A320/A321 FLEET DSC-32-30-10 P 7/8

FCOM ←D 17 DEC 24
 AIRCRAFT SYSTEMS
LANDING GEAR
A319/A320/A321
FLIGHT CREW
OPERATING MANUAL
UNOFFICIAL COPY
BRAKES AND ANTISKID - DESCRIPTION

BRAKING SCHEMATIC
Ident.: DSC-32-30-10-00001316.0003001 / 09 OCT 12
Applicable to: ALL

THY A319/A320/A321 FLEET DSC-32-30-10 P 8/8

FCOM E 17 DEC 24
 AIRCRAFT SYSTEMS
LANDING GEAR
A319/A320/A321
FLIGHT CREW
OPERATING MANUAL
UNOFFICIAL COPY
BRAKES AND ANTISKID - CONTROLS AND INDICATORS

CENTER INSTRUMENT PANEL

Ident.: DSC-32-30-20-00018635.0002001 / 28 NOV 23
Applicable to: ALL

A/SKID & N/W STRG sw

If green hydraulic pressure is available, then antiskid is available.

If green hydraulic pressure is lost, then:
‐ Yellow hydraulic pressure automatically takes over to supply the brakes
‐ Antiskid and nosewheel steering remain available
‐ Triple indicator shows yellow system brake pressure.

The yellow hydraulic system supplies pressure to the brakes.

‐ Antiskid is deactivated. To avoid wheel locking and limiting the risk of tire
burst, brake pressure is automatically limited to 1 000 PSI
‐ Nosewheel steering is lost
‐ Differential braking remains available through the pedals
‐ Triple indicator displays yellow system brake pressure.

THY A319/A320/A321 FLEET DSC-32-30-20 P 1/10

FCOM A→ 17 DEC 24
 AIRCRAFT SYSTEMS
LANDING GEAR
A319/A320/A321
FLIGHT CREW
OPERATING MANUAL
UNOFFICIAL COPY
BRAKES AND ANTISKID - CONTROLS AND INDICATORS

BRAKES and ACCU PRESS indicator

Brake pressure is only indicated when the yellow hydraulic system controls the brake pressure.
This is when the:
‐ Alternate braking system is activated, or
‐ Parking brake is applied.
Indicates the pressure in the yellow brake accumulator.

Indicates the yellow pressure delivered to the left and right

brakes, as measured downstream of the alternate servovalves.

AUTO BRK PANEL

Ident.: DSC-32-30-20-00018636.0002001 / 21 MAR 16
Applicable to: TC-JLZ, TC-JPI, TC-JPK, TC-JPP, TC-JPT, TC-JTS, TC-JTT, TC-JTU, TC-LBC, TC-LBD

THY A319/A320/A321 FLEET DSC-32-30-20 P 2/10

FCOM ← A to B → 17 DEC 24
 AIRCRAFT SYSTEMS
LANDING GEAR
A319/A320/A321
FLIGHT CREW
OPERATING MANUAL
UNOFFICIAL COPY
BRAKES AND ANTISKID - CONTROLS AND INDICATORS

(3) AUTO/BRK panel

The springloaded MAX, MED, and LO pushbutton switches arm the appropriate deceleration
rate. The usage for each mode are as follow:
‐ MAX mode is normally selected for takeoff.
In the case of an aborted takeoff, maximum pressure goes to the brakes, as soon as the
system generates the ground spoiler deployment order
‐ MED or LO mode is normally selected for landing:
• MED mode sends progressive pressure to the brakes 2 s after the ground spoilers deploy
in order to decelerate the aircraft at 3 m/s² (9.8 ft/s²)
• LO mode sends progressive pressure to the brakes 4 s after the ground spoilers deploy, in
order to decelerate the aircraft at 1.7 m/s² (5.6 ft/s²).
The lighting on the pushbutton switches are as follow:
ON light : comes on blue to indicate positive arming
DECEL light : comes on green when the actual deceleration is 80 % of the selected
rate
Note: On slippery runways, the predetermined deceleration may not
be reached, due to antiskid operation. In this case, the DECEL
light will not come on. This does not mean that autobrake is
not working.

Off : The corresponding autobrake mode is not armed

THY A319/A320/A321 FLEET DSC-32-30-20 P 3/10

FCOM ←B→ 17 DEC 24
 AIRCRAFT SYSTEMS
LANDING GEAR
A319/A320/A321
FLIGHT CREW
OPERATING MANUAL
UNOFFICIAL COPY
BRAKES AND ANTISKID - CONTROLS AND INDICATORS

AUTO BRK PANEL

Ident.: DSC-32-30-20-00018636.0004001 / 21 MAR 16
1 Applicable to: TC-JLS, TC-JLT, TC-JLU, TC-JLV, TC-JLY, TC-JMH, TC-JMI, TC-JMJ, TC-JMK, TC-JML, TC-JPH, TC-JPJ, TC-JPL,
TC-JPM, TC-JPN, TC-JPR, TC-JPS, TC-JPZ, TC-JRA, TC-JRB, TC-JRC, TC-JRD, TC-JRE, TC-JRF, TC-JRG, TC-JRH, TC-JRI, TC-JRJ,
TC-JRK, TC-JRL, TC-JRM, TC-JRN, TC-JRO, TC-JRP, TC-JRR, TC-JRS, TC-JRT, TC-JRU, TC-JRV, TC-JRY, TC-JRZ, TC-JSA, TC-JSB,
TC-JSC, TC-JSD, TC-JSE, TC-JSF, TC-JSG, TC-JSI, TC-JSJ, TC-JSK, TC-JSL, TC-JSM, TC-JSN, TC-JSO, TC-JSP, TC-JSR, TC-JSS,
TC-JST, TC-JSU, TC-JSV, TC-JSY, TC-JSZ, TC-JTA, TC-JTD, TC-JTE, TC-JTF, TC-JTG, TC-JTH, TC-JTI, TC-JTJ, TC-JTK, TC-JTL,
TC-JTM, TC-JTN, TC-JTO, TC-JTP, TC-JTR, TC-JTV, TC-JTY, TC-LBA, TC-LBB, TC-LBF, TC-LBG, TC-LBH, TC-LBJ, TC-LBK, TC-LPA,
TC-LPB, TC-LPC, TC-LPD, TC-LPE, TC-LPF, TC-LPG, TC-LPH, TC-LPI, TC-LPJ, TC-LPK, TC-LPL, TC-LPM, TC-LPN, TC-LPO, TC-LPP,
TC-LPR, TC-LSA, TC-LSB, TC-LSC, TC-LSD, TC-LSE, TC-LSF, TC-LSG, TC-LSH, TC-LSJ, TC-LSK, TC-LSL, TC-LSM, TC-LSN, TC-LSO,
TC-LSP, TC-LSR, TC-LSS, TC-LST, TC-LSU, TC-LSV, TC-LSY, TC-LSZ, TC-LTA, TC-LTB, TC-LTC, TC-LTD, TC-LTE, TC-LTF, TC-LTG,
TC-LTH, TC-LTI, TC-LTJ, TC-LTK, TC-LTL, TC-LTM, TC-LTN, TC-LTO, TC-LTP, TC-LTR, TC-LTS, TC-LTT, TC-LTU, TC-LTV, TC-LTY,
TC-LTZ, TC-LUA, TC-LUB, TC-LUC, TC-LUE, TC-LUI, TC-LUJ, TC-LUK, TC-LUL, TC-LUM, TC-LUN, TC-LUO, TC-LUP, TC-LUR, TC-LUS,
TC-LUU, TC-LUV, TC-LUY, TC-LUZ, TLBI

(3) AUTO/BRK panel

The springloaded MAX, MED, and LO pushbutton switches arm the appropriate deceleration
rate. The usage for each mode are as follow:
‐ MAX mode is normally selected for takeoff.
In the case of an aborted takeoff, maximum pressure goes to the brakes, as soon as the
system generates the ground spoiler deployment order
‐ MED or LO mode is normally selected for landing:
• MED mode sends progressive pressure to the brakes 2 s after the ground spoilers deploy
in order to decelerate the aircraft at 3 m/s² (9.8 ft/s²)
• LO mode sends progressive pressure to the brakes 2 s after the ground spoilers deploy, in
order to decelerate the aircraft at 2 m/s² (6.6 ft/s²).
The lighting on the pushbutton switches are as follow:
ON light : comes on blue to indicate positive arming

THY A319/A320/A321 FLEET DSC-32-30-20 P 4/10

FCOM ←B→ 17 DEC 24
 AIRCRAFT SYSTEMS
LANDING GEAR
A319/A320/A321
FLIGHT CREW
OPERATING MANUAL
UNOFFICIAL COPY
BRAKES AND ANTISKID - CONTROLS AND INDICATORS

DECEL light : comes on green when the actual deceleration is 80 % of the selected
rate
Note: On slippery runways, the predetermined deceleration may not
be reached, due to antiskid operation. In this case, the DECEL
light will not come on. This does not mean that autobrake is
not working.

Off : The corresponding autobrake mode is not armed

BRAKE FAN 
Ident.: DSC-32-30-20-00018637.0001001 / 21 MAR 16
Applicable to: ALL

(4) BRK FAN pb-sw 

ON light : The brake fans run if the lefthand main landing gear is down and locked
Off : The brake fans stop
HOT : This amber light comes on when the brakes get too hot (A caution appears on
light ECAM, also)

THY A319/A320/A321 FLEET DSC-32-30-20 P 5/10

FCOM ← B to C 17 DEC 24
 AIRCRAFT SYSTEMS
LANDING GEAR
A319/A320/A321
FLIGHT CREW
OPERATING MANUAL
UNOFFICIAL COPY
BRAKES AND ANTISKID - CONTROLS AND INDICATORS

PEDESTAL
Ident.: DSC-32-30-20-00018638.0001001 / 21 MAR 16
Applicable to: ALL

(1) PARKING BRK handle

Flight crew pulls this handle, then turns it clockwise, to apply the parking brake.
The ECAM memo page displays “PARK BRK”.
CAUTION If the pointer is not at ON, the parking brake is not on.

THY A319/A320/A321 FLEET DSC-32-30-20 P 6/10

FCOM D 17 DEC 24
 AIRCRAFT SYSTEMS
LANDING GEAR
A319/A320/A321
FLIGHT CREW
OPERATING MANUAL
UNOFFICIAL COPY
BRAKES AND ANTISKID - CONTROLS AND INDICATORS

WHEEL SD PAGE
Ident.: DSC-32-30-20-00018639.0008001 / 21 MAR 16
Applicable to: ALL

(1) Release indicators

It appears in amber in case of brake released fault.
(2) ANTI SKID indication

(A) ANTISKID label

It appears in amber, a long with an ECAM caution, in case of a total BSCU failure, or
when the A/SKID & N/W STRG sw is OFF, or if the BSCU detects an ANTI-SKID failure,
or in case of normal braking and yellow hydraulic system low pressure.
It appears in green in case of autobrake, normal braking, or alternate braking failure, and
antiskid is still available.
(B) BSCU channel indication
When ANTISKID label is displayed, the number of the failed system(s) is (are) displayed
in amber, if any.
(3) AUTO BRK
This legend appears:
‐ In green when auto brake is armed, or
‐ Flashing green for 10 s after autobrake disengagement, or
‐ In amber, along with an ECAM caution, to indicate a system failure.
MED, LO, or MAX appears underneath in green to show which rate has been selected.

THY A319/A320/A321 FLEET DSC-32-30-20 P 7/10

FCOM E→ 17 DEC 24
 AIRCRAFT SYSTEMS
LANDING GEAR
A319/A320/A321
FLIGHT CREW
OPERATING MANUAL
UNOFFICIAL COPY
BRAKES AND ANTISKID - CONTROLS AND INDICATORS

(4) Wheel number

This white number identifies individual wheels of the main landing gear.
(5) Brake temperature
‐ Temperature normally appears in green.
‐ Green arc appears on the hottest wheel when one brake temperature exceeds 100 °C.
‐ Green arc becomes amber, and an ECAM caution appears, when the corresponding brake
temperature exceeds 300 °C.
(6) NORM BRK indication

(A) NORM BRK label

This indication appears in green when autobrake or alternate braking is failed, and
normal braking is still available.
The legend appears in amber when normal braking is failed due to total BSCU failure, or
to the loss of the green hydraulic pressure, or to the loss of antiskid.
(B) NORM BRK hydraulic supply indication
G is displayed when the NORM BRK label is displayed. It is green when green hydraulic
pressure is available and amber, in case of green hydraulic low pressure.
(7)

(A) ALTN BRK label

This indication appears in green, if the braking system is in alternate mode and not failed,
or in case autobrake or normal braking is failed and alternate braking is still available.
This indication appears in amber when alternate braking is failed.
(B) ALTN BRK hydraulic supply indication
Y is displayed when the ALTN BRK label is displayed. It is green when yellow hydraulic
pressure is available and amber, in case of yellow hydraulic low pressure.

THY A319/A320/A321 FLEET DSC-32-30-20 P 8/10

FCOM ←E→ 17 DEC 24
 AIRCRAFT SYSTEMS
LANDING GEAR
A319/A320/A321
FLIGHT CREW
OPERATING MANUAL
UNOFFICIAL COPY
BRAKES AND ANTISKID - CONTROLS AND INDICATORS

(C) ACCU indications

(*) Appears in green, when the ALTN BRK label is displayed, and the yellow hydraulic
pressure is available.
Appears in amber, with no arrow, when the yellow hydraulic system and the
accumulator are in low pressure.
(**) Appears in green when the alternate braking is pressurized by the yellow
accumulator.

AUDIO INDICATORS
Ident.: DSC-32-30-20-00025022.0001001 / 13 JUN 24
2 Applicable to: TC-JLS, TC-JLT, TC-JLU, TC-JLV, TC-JLY, TC-JLZ, TC-JMH, TC-JMI, TC-JMJ, TC-JMK, TC-JML, TC-JPH, TC-JPI,
TC-JPJ, TC-JPL, TC-JPM, TC-JPN, TC-JPP, TC-JPR, TC-JPS, TC-JPT, TC-JPZ, TC-JRA, TC-JRB, TC-JRC, TC-JRD, TC-JRE, TC-JRF,
TC-JRG, TC-JRH, TC-JRI, TC-JRJ, TC-JRK, TC-JRL, TC-JRM, TC-JRN, TC-JRO, TC-JRP, TC-JRR, TC-JRS, TC-JRU, TC-JRY, TC-JSA,
TC-JSC, TC-JSD, TC-JSE, TC-JSF, TC-JSG, TC-JSI, TC-JSJ, TC-JSK, TC-JSL, TC-JSM, TC-JSN, TC-JSO, TC-JSP, TC-JSR, TC-JSS,
TC-JST, TC-JSU, TC-JSV, TC-JSY, TC-JSZ, TC-JTA, TC-JTD, TC-JTE, TC-JTF, TC-JTG, TC-JTH, TC-JTI, TC-JTJ, TC-JTK, TC-JTL,
TC-JTM, TC-JTN, TC-JTO, TC-JTP, TC-JTR, TC-JTV, TC-JTY, TC-LBA, TC-LBB, TC-LBD, TC-LBH, TC-LPA, TC-LPB, TC-LPC, TC-LPD,
TC-LPE, TC-LPF, TC-LPG, TC-LPH, TC-LPI, TC-LPJ, TC-LPK, TC-LPL, TC-LPM, TC-LPN, TC-LPO, TC-LPP, TC-LPR, TC-LSG, TC-LSK,
TC-LSM, TC-LSN, TC-LSP, TC-LSS, TC-LSU, TC-LSV, TC-LSY, TC-LTB, TC-LTC, TC-LTD, TC-LTE, TC-LTG, TC-LTI, TC-LTJ, TC-LTL,
TC-LTM, TC-LTN, TC-LTO, TC-LTP, TC-LTR, TC-LTS, TC-LTT, TC-LTU, TC-LTV, TC-LTY, TC-LTZ, TC-LUB, TC-LUE, TC-LUJ, TC-LUK,
TC-LUL, TC-LUM, TC-LUN, TC-LUO, TC-LUP, TC-LUR, TC-LUV, TC-LUY, TC-LUZ, TLBI

Audio Indicator Condition or Cause Duration

Auto Brake Off (Synthetic Voice) The flight crew disconnects the Sounds one time
autobrake at a speed above 33 kt, after
touchdown or after RTO.
Associated with the AUTO BRK OFF
memo.
The master caution light comes on for
3 s and a single chime sounds.
Auto Brake Off, Auto Brake Off The autobrake is disconnected due to a Sounds one time
(Synthetic Voice) system failure after touchdown or after
RTO.
Associated with the AUTO BRK OFF
memo.
The master caution light comes on and
a single chime sounds.

THY A319/A320/A321 FLEET DSC-32-30-20 P 9/10

FCOM ← E to F 17 DEC 24
 AIRCRAFT SYSTEMS
LANDING GEAR
A319/A320/A321
FLIGHT CREW
OPERATING MANUAL
UNOFFICIAL COPY
BRAKES AND ANTISKID - CONTROLS AND INDICATORS

MEMO DISPLAY
Ident.: DSC-32-30-20-A-00016854.0001001 / 22 MAR 16
Applicable to: ALL

AUTO BRK LO/MED/MAX : This memo appears in green, depending on the selection of the
AUTO BRK pb.
AUTO BRK OFF
Ident.: DSC-32-30-20-A-00016855.0001001 / 22 MAR 16
3 Applicable to: TC-JPK, TC-JRT, TC-JRV, TC-JRZ, TC-JSB, TC-JTS, TC-JTT, TC-JTU, TC-LBC, TC-LBF, TC-LBG, TC-LBJ, TC-LBK,
TC-LSA, TC-LSB, TC-LSC, TC-LSD, TC-LSE, TC-LSF, TC-LSH, TC-LSJ, TC-LSL, TC-LSO, TC-LSR, TC-LST, TC-LSZ, TC-LTA, TC-LTF,
TC-LTH, TC-LTK, TC-LUA, TC-LUC, TC-LUI, TC-LUS, TC-LUU

AUTO BRK OFF : This memo appears in green if the auto brake is failed.
Ident.: DSC-32-30-20-A-00016855.0002001 / 22 FEB 22
4 Applicable to: TC-JLS, TC-JLT, TC-JLU, TC-JLV, TC-JLY, TC-JLZ, TC-JMH, TC-JMI, TC-JMJ, TC-JMK, TC-JML, TC-JPH, TC-JPI,
TC-JPJ, TC-JPL, TC-JPM, TC-JPN, TC-JPP, TC-JPR, TC-JPS, TC-JPT, TC-JPZ, TC-JRA, TC-JRB, TC-JRC, TC-JRD, TC-JRE, TC-JRF,
TC-JRG, TC-JRH, TC-JRI, TC-JRJ, TC-JRK, TC-JRL, TC-JRM, TC-JRN, TC-JRO, TC-JRP, TC-JRR, TC-JRS, TC-JRU, TC-JRY, TC-JSA,
TC-JSC, TC-JSD, TC-JSE, TC-JSF, TC-JSG, TC-JSI, TC-JSJ, TC-JSK, TC-JSL, TC-JSM, TC-JSN, TC-JSO, TC-JSP, TC-JSR, TC-JSS,
TC-JST, TC-JSU, TC-JSV, TC-JSY, TC-JSZ, TC-JTA, TC-JTD, TC-JTE, TC-JTF, TC-JTG, TC-JTH, TC-JTI, TC-JTJ, TC-JTK, TC-JTL,
TC-JTM, TC-JTN, TC-JTO, TC-JTP, TC-JTR, TC-JTV, TC-JTY, TC-LBA, TC-LBB, TC-LBD, TC-LBH, TC-LPA, TC-LPB, TC-LPC, TC-LPD,
TC-LPE, TC-LPF, TC-LPG, TC-LPH, TC-LPI, TC-LPJ, TC-LPK, TC-LPL, TC-LPM, TC-LPN, TC-LPO, TC-LPP, TC-LPR, TC-LSG, TC-LSK,
TC-LSM, TC-LSN, TC-LSP, TC-LSS, TC-LSU, TC-LSV, TC-LSY, TC-LTB, TC-LTC, TC-LTD, TC-LTE, TC-LTG, TC-LTI, TC-LTJ, TC-LTL,
TC-LTM, TC-LTN, TC-LTO, TC-LTP, TC-LTR, TC-LTS, TC-LTT, TC-LTU, TC-LTV, TC-LTY, TC-LTZ, TC-LUB, TC-LUE, TC-LUJ, TC-LUK,
TC-LUL, TC-LUM, TC-LUN, TC-LUO, TC-LUP, TC-LUR, TC-LUV, TC-LUY, TC-LUZ, TLBI

AUTO BRK OFF Appears if:

‐ The flight crew disconnects the autobrake, or
‐ The autobrake fails.

Ident.: DSC-32-30-20-A-00016856.0001001 / 22 MAR 16

Applicable to: ALL

BRK FAN : This memo appears in green if the BRK FAN pb  is ON.
Ident.: DSC-32-30-20-A-00016857.0001001 / 22 MAR 16
Applicable to: ALL

PARK BRK : This memo appears in green, if the parking brake is ON, during flight
phases 1, 2, 9 and 10.

THY A319/A320/A321 FLEET DSC-32-30-20 P 10/10

FCOM G 17 DEC 24