Bleeding of the High Pressure Alternate Braking System

TASK 32-43-00-870-002-A
Bleeding of the High Pressure Alternate Braking System

WARNING: MAKE SURE THAT THE GROUND SAFETY-LOCKS ARE IN POSITION ON THE LANDING GEAR. THIS WILL PREVENT UNWANTED MOVEMENT OF THE LANDING GEAR, AND THUS POSSIBLE INJURY TO PERSONS AND DAMAGE TO THE AIRCRAFT AND/OR EQUIPMENT.

WARNING: MAKE SURE THAT THE TRAVEL RANGES OF THE FLIGHT CONTROLS SURFACES ARE CLEAR. MOVEMENT OF FLIGHT CONTROLS CAN CAUSE INJURY TO PERSONS AND/OR DAMAGE TO EQUIPMENT.

WARNING: MAKE SURE THAT THE CONTROLS AGREE WITH THE POSITION OF THE ITEMS THEY OPERATE BEFORE YOU PRESSURIZE A HYDRAULIC SYSTEM. UNWANTED MOVEMENT OF HYDRAULICALLY OPERATED ITEMS CAN CAUSE SERIOUS INJURY AND/OR DAMAGE.

WARNING: BE CAREFUL WHEN YOU USE CONSUMABLE MATERIALS. OBEY THE MATERIAL MANUFACTURER'S INSTRUCTIONS AND YOUR LOCAL REGULATIONS.

1. Reason for the Job
To bleed the braking system after all maintenance operations of the alternate braking system.
2. Job Set-up Information
A. Fixtures, Tools, Test and Support Equipment

REFERENCE	QTY	DESIGNATION
No specific	AR	ACCESS PLATFORM 2M (6 FT) - ADJUSTABLE
No specific	AR	CONTAINER 10 L(2 1/2 USGAL)
No specific	1	CONTAINER 5 L (1.32 USGAL)
No specific	AR	HOSE - BLEED
No specific	AR	WARNING NOTICE(S)
No specific	Torque wrench: range to between 0.11 and 0.08 m.daN (9.73 and 7.08 lbf.in )
No specific	Torque wrench: range to between 0.104 and 0.096 m.daN (9.20 and 8.50 lbf.in )
No specific	Torque wrench: range to between 0.30 and 0.25 m.daN (26.55 and 22.12 lbf.in )
No specific	Torque wrench: range to between 0.58 and 0.55 m.daN (51.33 and 48.67 lbf.in )
No specific	Torque wrench: range to between 0.85 and 0.56 m.daN (75.22 and 49.56 lbf.in )
No specific	Torque wrench: range to between 0.68 and 0.565 m.daN (60.18 and 50.00 lbf.in )
No specific	Torque wrench: range to between 0.7425 and 0.6075 m.daN (65.71 and 53.76 lbf.in )
No specific	Torque wrench: range to between 0.72 and 0.68 m.daN (63.72 and 60.18 lbf.in )
No specific	Torque wrench: range to between 4 and 3.85 m.daN (29.50 and 28.39 lbf.ft )

B. Consumable Materials

REFERENCE	DESIGNATION
(Material No.08BAA9)	Non Aqueous Cleaner-General - -
(Material No.14QFB1)	Wire-Locking Dia: 0.8 mm CRES Nickel Alloy -
(Material No.14SBA1)	Textile-Lint free Cotton -

C. Expendable Parts

FIG.ITEM	DESIGNATION	IPC-CSN
3	PACKING	AIPC 32-43-16-01-080
6	PACKING	AIPC 32-43-16-01-080

D. Referenced Information

REFERENCE	DESIGNATION
TASK 12-12-29-611-001-A	Fill the Hydraulic Fluid Reservoir with a Hand Pump
TASK 24-41-00-861-002-A	Energize the Aircraft Electrical Circuits from the External Power
TASK 24-41-00-861-002-A-01	Energize the Aircraft Electrical Circuits from the APU
TASK 24-41-00-861-002-A-02	Energize the Aircraft Electrical Circuits from Engine 1(2)
TASK 29-10-00-863-002-A	Pressurize the Yellow Hydraulic System with a Hydraulic Ground Power-Cart
TASK 29-10-00-864-001-A	Depressurize the Green Hydraulic System
TASK 29-10-00-864-002-A	Depressurize the Yellow Hydraulic System
TASK 29-14-00-614-001-A	Depressurization of the Hydraulic Reservoirs
TASK 29-23-00-864-001-A	Depressurize the Green and Yellow Hydraulic Systems after Operation of the PTU
TASK 29-24-00-863-001-A	Pressurize the Yellow Hydraulic System with the Electric Pump
TASK 32-43-00-710-001-A	Operational Check of Alternate Braking System
TASK 32-43-16-600-001-A	Reactivation of the Alternate-Brake Safety-Valve
TASK 32-43-16-600-001-A-01	Reactivation of the Alternate-Brake Safety-Valve
TASK 32-43-32-600-001-A	Reactivation of the Alternate-Brake Manifold Safety-Valve
Brake Unit Bleed Valves
Alternate Safety Valve - Bleeding ** ON A/C NOT FOR ALL

3. Job Set-up
Subtask 32-43-00-860-052-A ** ON A/C NOT FOR ALL

A. Aircraft Maintenance Configuration
(1) Energize the aircraft electrical circuits (Ref. AMM TASK 24-41-00-861-002)
(2) On the panel 400VU, make sure that the Landing Gear control-lever is set to DOWN.
(3) On the panel 110VU, make sure that the PARK BRK control switch is set to OFF.
(4) Pressurize the Yellow hydraulic system (Ref. AMM TASK 29-10-00-863-002) or (Ref. AMM TASK 29-24-00-863-001).

Make sure that the Green hydraulic system is depressurized (Ref. AMM TASK 29-10-00-864-001).

(5) If you do the bleeding after rupture of a hydraulic line, you must do the reactivation of the Yellow brake safety valve (Ref. AMM TASK 32-43-16-600-001).

Subtask 32-43-00-860-052-B ** ON A/C NOT FOR ALL

A. Aircraft Maintenance Configuration
(1) Energize the aircraft electrical circuits (Ref. AMM TASK 24-41-00-861-002).
(2) On the panel 400VU, make sure that the Landing Gear control-lever is set to DOWN.
(3) On the panel 110VU, make sure that the PARK BRK control switch is set to OFF.
(4) Pressurize the Yellow hydraulic system (Ref. AMM TASK 29-10-00-863-002) or (Ref. AMM TASK 29-24-00-863-001).

Make sure that the Green hydraulic system is depressurized (Ref. AMM TASK 29-10-00-864-001).

(5) If you do the bleeding after rupture of a hydraulic line, you must do the reactivation of the Yellow brake safety valve (Ref. AMM TASK 32-43-32-600-001).

Subtask 32-43-00-941-053-A

B. Safety Precautions
(1) Put the WARNING NOTICE(S) in position to tell persons not to operate the landing gear.
(2) Put the WARNING NOTICE(S) in position to tell persons not to pressurize the Green hydraulic system.

4. Procedure
Subtask 32-43-00-870-053-A

A. Bleeding of the Alternate Braking System

NOTE: Bleed port for the alternate brake system (Yellow Hydraulic System) is the forward bleed port.

(1) Remove the bleed screw plug from the related brake unit.
(2) Connect a vinyl hose and put one end in a CONTAINER 5 L (1.32 USGAL) that contains HYDRAULIC FLUID (Material N°02-003).
(3) Push down the brake pedal related to the brake to bleed moderately.
(4) Release the bleed screw half a turn more, to let the fluid flow. Do this until there are no air bubbles in the fluid that you can easily see.

NOTE: Airbus recommend that you bleed a minimum of 0.5 l (0.1321 USgal), but you can bleed more than this amount.

NOTE: It is possible that the fluid you bleed will have froth and also come out as an intermittent flow that alternates with large air bubbles.

(5) You must continue to bleed the fluid until the flow is constant.

NOTE: Fluid that contains very small bubbles of air can cause the fluid to be white. When this fluid becomes stable in the container, it shows its normal color.

NOTE: The safety valve can close if the flow rate is more than 6 l (1.5850 USgal) per minute during the bleeding operation.

(6) Keep the pressure on the brake and tighten the bleed screw.
(7) Release the brake pedal.
(8) On panel 110VU, set the PARK BRK control switch to ON.
(9) On panel 400VU, make sure that brake pressure indication on the Yellow brake-pressure triple indicator is correct.
(a) If necessary, pressurize the brake accumulator with Yellow pump (Ref. AMM TASK 29-10-00-863-002) or (Ref. AMM TASK 29-24-00-863-001).
(10) Slowly release the bleed screw valve until the hydraulic fluid flows smoothly. Let the fluid flow until it has no air bubbles.
(11) Close the bleed screw and on panel 110VU, set the PARK BRK control switch to OFF.
(12) TORQUE the bleed screw:

to between 0.7425 and 0.6075 m.daN (65.71 and 53.76 lbf.in ) for MESSIER-BUGATTY brakes
to between 0.72 and 0.68 m.daN (63.72 and 60.18 lbf.in ) for GOODRICH brakes
to between 0.85 and 0.56 m.daN (75.22 and 49.56 lbf.in ) for MESSIER-GOODRICH brakes
to between 0.68 and 0.565 m.daN (60.18 and 50.00 lbf.in ) for MABS brakes
to between 0.7425 and 0.6075 m.daN (65.71 and 53.76 lbf.in ) for SAFRAN brakes.

(13) If necessary, do the operations again until all the air is removed from the braking system.
(14) Disconnect the vinyl hose. Remove all signs of the fluid from the bleed screw.
(15) Install the bleed screw plug.
(16) TORQUE the bleed screw plug:

to between 0.30 and 0.25 m.daN (26.55 and 22.12 lbf.in ) for MESSIER-BUGGATTI brakes
to between 0.104 and 0.096 m.daN (9.20 and 8.50 lbf.in ) for GOODRICH brakes
to between 0.11 and 0.08 m.daN (9.73 and 7.08 lbf.in ) for MESSIER-GOODRICH brakes
to between 0.58 and 0.55 m.daN (51.33 and 48.67 lbf.in ) for MABS brakes
to between 0.30 and 0.25 m.daN (26.55 and 22.12 lbf.in ) for SAFRAN brakes.

Subtask 32-43-00-870-058-A ** ON A/C NOT FOR ALL

B. Bleeding of the Alternate-Brake Safety Valve

Alternate Safety Valve - Bleeding ** ON A/C NOT FOR ALL

WARNING: OBEY THE HYDRAULIC SAFETY PROCEDURES.

CAUTION: MAKE SURE THAT THE FLUID DOES NOT STAY ON THE AIRCRAFT STRUCTURE. IF THE FLUID GETS ON THE AIRCRAFT STRUCTURE, WASH IT OFF IMMEDIATELY WITH SOAP AND WATER.

CAUTION: DO NOT PUSH THE BRAKEPEDALS WHILE YOU BLEED THE SAFETY VALVE. MOVEMENT OF THE PEDALS WILL INCREASE THE PRESSURE IN THE SAFETY VALVE AND WILL CAUSE DAMAGE TO THE SAFETY VALVE.

(1) Bleeding of alternate-brake safety valve P/N C24757000.
(a) Fully push, then release the two brake pedals. Do this ten times.
(b) Depressurize the Green and Yellow hydraulic systems.
(Ref. AMM TASK 29-23-00-864-001).
(c) Release the pressure from the parking brake accumulator:

Operate the manual depressurization button on brake relief valve 3067GM to release the pressure.

(d) On panel 400VU, make sure that the triple indicator shows a zero pressure.

CAUTION: DO NOT PRESSURIZE THE HYDRAULIC RESERVOIRS TO MORE THAN 1 BAR (14.5 PSI). HIGHER PRESSURE WILL CAUSE DAMAGE TO THE SAFETY VALVE.

(e) Decrease the pressure of the Yellow hydraulic reservoir to between 0.5 bar (7.2519 psi) and 1 bar (14.5038 psi) (Ref. AMM TASK 29-14-00-614-001).
(f) Put an ACCESS PLATFORM 2M (6 FT) - ADJUSTABLE in position below the applicable zone Z571(Z671).
(g) Put a CONTAINER 10 L(2 1/2 USGAL) in an applicable position below the related alternate-brake safety-valve.
(h) Remove the dust cap (1) from the applicable alternate-brake safety valve.
(i) Remove lockwire.

WARNING: USE PROTECTIVE GOGGLES AND GLOVES WHEN YOU REMOVE OR INSTALL LOCKWIRE. EACH TIME YOU CUT LOCKWIRE, REMOVE AND DISCARD IT IMMEDIATELY. LOOSE LOCKWIRE CAN CUT YOU OR MAKE YOU BLIND, AND/OR CAN CAUSE DAMAGE.

1 Cut, remove and discard the lockwire from the bleed screw (2).
(j) Put a HOSE - BLEED between the bleed screw (2) and the CONTAINER 10 L(2 1/2 USGAL).
(k) Slowly loosen the bleed screw (2) to release the hydraulic pressure.
(l) When the fluid flow stops, do a check of the packing (3).
1 If the packing (3) is damaged, do the steps that follow:
a Remove the bleed screw (2).
b Remove and discard the packing (3) from the bleed screw (2).
c Install a new AIPC 32-43-16-01-080 PACKING (3) on the bleed screw (2).
d Loosely install the bleed screw (2).
(m) Tighten the bleed screw (2) until it touches the alternate-brake safety valve (4), then tighten it to one-eighth of a turn.
(n) Remove the HOSE - BLEED and the CONTAINER 10 L(2 1/2 USGAL).
(o) Use a clean Textile-Lint free Cotton - (Material No.14SBA1) made moist with Non Aqueous Cleaner-General - - (Material No.08BAA9) to remove the unwanted hydraulic fluid from the safety valve and the adjacent area.
(p) Install lockwire.

1 Safety the bleed screw (2) with 14QFB1Wire-Locking Dia: 0.8 mm CRES Nickel Alloy -.
(q) Install the dust cap (1) and tighten it.

(2) Bleeding of alternate-brake safety valve P/N C25243002-2 or P/N C25243102
(a) Fully push, then release the two brake pedals. Do this ten times.
(b) Make sure that the Yellow hydraulic system is depressurized.
(Ref. AMM TASK 29-23-00-864-001).
(c) Release the pressure from the parking brake accumulator:

Operate the manual depressurization button on brake relief valve 3067GM to release the pressure.

(d) On panel 400VU, make sure that the triple indicator shows a zero pressure.

CAUTION: DO NOT PRESSURIZE THE HYDRAULIC RESERVOIRS TO MORE THAN 1 BAR (14.5 PSI). HIGHER PRESSURE WILL CAUSE DAMAGE TO THE SAFETY VALVE.

(e) Decrease the pressure of the Yellow hydraulic reservoir to between 0.5 bar (7.2519 psi) and 1 bar (14.5038 psi) (Ref. AMM TASK 29-14-00-614-001).
(f) Remove lockwire.

1 Cut, remove and discard the lockwire from the plug (5).
(g) Slowly loosen the plug (5) to release the hydraulic pressure.
1 Do not loosen the plug (5) more than 2.5 turns.
(h) When the fluid flow stops, do a check of the packing (6).
1 If the packing (6) is damaged, do the steps that follow:
a Remove the plug (5).
b Remove and discard the packing (6) from the plug (5).
c Install a new AIPC 32-43-16-01-080 PACKING (6) on the plug (5).
(i) Loosely install the plug (5).
(j) TORQUE the plug (5) to between 4 and 3.85 m.daN (29.50 and 28.39 lbf.ft )

.
(k) Use a clean Textile-Lint free Cotton - (Material No.14SBA1) made moist with Non Aqueous Cleaner-General - - (Material No.08BAA9) to remove unwanted hydraulic fluid from the safety valve and the adjacent area.
(l) Install lockwire.

1 Safety the plug (5) with 14QFB1Wire-Locking Dia: 0.8 mm CRES Nickel Alloy -.

Subtask 32-43-00-210-055-A

C. Fluid Level Check
(1) Make sure that the level of the fluid in the reservoir of the Yellow hydraulic system is correct. If necessary, fill the hydraulic fluid reservoir (Ref. AMM TASK 12-12-29-611-001).

Subtask 32-43-00-710-053-A ** ON A/C NOT FOR ALL

D. Test
(1) Do an operational test of the alternate braking system with the anti-skid (Ref. AMM TASK 32-43-00-710-001).

NOTE: Do only the test of the alternate braking for the related brake unit (Para. 4. A.(1) to A.(2)).

NOTE: The safety valve can close if the flow rate is more than 6 l (1.59 USgal) in one minute during the bleeding operation. If there is no pressure at the brake during the test, it is necessary to do reactivation of the related safety valve.

(a) If necessary, do the reactivation procedure of the related safety valve (Ref. AMM TASK 32-43-16-600-001).

NOTE: The first procedure is applicable only to part numbers C24757000 and C25243002-2 and the second procedure is applicable to all part numbers.

(b) During the test, make sure that there are no leaks from the bleed valve.

Subtask 32-43-00-710-053-B ** ON A/C NOT FOR ALL

D. Test
(1) Do an operational test of the alternate braking system with the anti-skid (Ref. AMM TASK 32-43-00-710-001).

NOTE: Do only the test of the alternate braking for the related brake unit (Para. 4. A.(1) to A.(2)).

(a) If necessary, do the reactivation procedure of the related safety valve (Ref. AMM TASK 32-43-32-600-001).
(b) During the test, make sure that there are no leaks from the bleed valve.

Subtask 32-43-00-860-053-A

E. Aircraft Maintenance Configuration
(1) Depressurize the Yellow hydraulic system (Ref. AMM TASK 29-10-00-864-002).

5. Close-up
Subtask 32-43-00-942-054-A

A. Removal of Equipment
(1) Make sure that the work area is clean and clear of tools and other items.
(2) Remove the WARNING NOTICE(S).
(3) Remove the fluid container.
(4) Remove the access platform(s).
(5) Remove the ground support and maintenance equipment, the special and standard tools and all other items.

[Rev.10 from 2021] 2026.04.01 00:48:36 UTC