Flushing of the Green Hydraulic System of the Trimmable Horizontal Stabilizer (THS) Actuator

TASK 12-36-29-170-012-A
Flushing of the Green Hydraulic System of the Trimmable Horizontal Stabilizer (THS) Actuator

WARNING: PUT THE SAFETY DEVICES AND THE WARNING NOTICES IN POSITION BEFORE YOU START A TASK ON OR NEAR:

THE FLIGHT CONTROLS
THE FLIGHT CONTROL SURFACES
THE LANDING GEAR AND THE RELATED DOORS
COMPONENTS THAT MOVE.

MOVEMENT OF COMPONENTS CAN KILL OR CAUSE INJURY TO PERSONS AND/OR CAN CAUSE DAMAGE TO THE EQUIPMENT.

WARNING: OBEY THE HYDRAULIC SAFETY PROCEDURES.

WARNING: DO NOT GET THE FLUID ON YOUR SKIN OR IN YOUR EYES. IF YOU DO:

FLUSH IT AWAY WITH CLEAN WATER
GET MEDICAL AID.

FIN: 9CE

1. Reason for the Job
To flush the Green hydraulic system after a failure in that part of the THS actuator 9CE.
2. Job Set-up Information
A. Fixtures, Tools, Test and Support Equipment

REFERENCE	QTY	DESIGNATION
No specific	1	ACCESS PLATFORM 2M (6 FT)
No specific	1	ACCESS PLATFORM 4M (13 FT)
No specific	1	CONTAINER 5 L (1.32 USGAL)
No specific	1	LOCALLY MANUFACTURED - ADAPTER
No specific	AR	PLUG - BLANKING
No specific	AR	SAFETY BARRIER(S)
No specific	1	WARNING NOTICE(S)
ALT29000001	1	HYD GRND PWR UNIT3000

B. Consumable Materials

REFERENCE	DESIGNATION
No specific	corrosion-resistant steel lockwire 0.8 mm (0.032 in) dia

C. Work Zones and Access Panels

ZONE/ACCESS	ZONE DESCRIPTION
197CB, 312AR

D. Referenced Information

REFERENCE	DESIGNATION
TASK 24-41-00-862-002-A	De-energize the Aircraft Electrical Circuits Supplied from the External Power
TASK 24-41-00-862-002-A-01	De-energize the Aircraft Electrical Circuits Supplied from the APU
TASK 24-41-00-862-002-A-02	De-energize the Aircraft Electrical Circuits Supplied from the Engine 1(2)
TASK 29-00-00-910-002-A	Safety Procedures of the Hydraulic System
TASK 29-10-00-863-001-A	Pressurize the Green Hydraulic System with a Hydraulic Ground Power-Cart
TASK 29-10-00-864-001-A	Depressurize the Green Hydraulic System
TASK 29-11-44-610-001-A	Servicing of the LP-Filter
TASK 29-14-00-614-001-A	Depressurization of the Hydraulic Reservoirs
TASK 29-23-00-863-001-A	Pressurize the Green Hydraulic System from the Yellow Hydraulic System through the PTU with the Electric Pump
TASK 29-23-00-864-001-A	Depressurize the Green and Yellow Hydraulic Systems after Operation of the PTU
TASK 32-12-00-010-001-A	Open the Main Gear Doors for Access
TASK 32-12-00-410-001-A	Close the Main Gear Doors after Access
Green Hydraulic System of the THS Actuator 9CE - Flushing Schematic

3. Job Set-up
Subtask 12-36-29-860-083-A

A. Aircraft Maintenance Configuration
(1) Obey the hydraulic safety procedures (Ref. AMM TASK 29-00-00-910-002).
(2) Depressurize the Green hydraulic system (Ref. AMM TASK 29-10-00-864-001).
(3) Depressurize the reservoir of the Green hydraulic system (Ref. AMM TASK 29-14-00-614-001).
(4) De-energize the aircraft electrical circuits (Ref. AMM TASK 24-41-00-862-002).
(5) Put the WARNING NOTICE(S) in position.
(6) As necessary, use the applicable SAFETY BARRIERS, specified by the operator's instructions and your local regulations.
(7) Put the ACCESS PLATFORM 4M (13 FT) in position at the Zone 310.

Subtask 12-36-29-010-095-A

B. Get Access
(1) Open the access door 312AR.
(2) Open the left MLG door (Ref. AMM TASK 32-12-00-010-001).
(3) Open the access door 197CB.

Subtask 12-36-29-860-084-A

C. Preparation for the Flushing Procedure
(1) Put the ACCESS PLATFORM 2M (6 FT) in position at Zone 147.
(2) Put a CONTAINER 5 L (1.32 USGAL) in position to collect the hydraulic fluid below:

the THS actuator 9CE and
the LP manifold 1003GM.

(3) Remove and discard the lockwire from the hydraulic connections of the valve block (of the Green hydraulic system) at the THS actuator 9CE.
(4) Disconnect the pressure line from the valve block.
(5) Disconnect the return line from the valve block.
(6) Disconnect the return line from the LP manifold 1003GM.
(7) Connect the pressure line to the return line at the THS actuator 9CE with an union.

CAUTION: MAKE SURE THAT THE FLOW RATE AND THE SUPPLY PRESSURE ON THE GROUND HYDRAULIC CART ARE SET TO A MINIMUM.

(8) Put the ALT29000001 HYD GRND PWR UNIT3000 in position as necessary.
(9) Connect the pressure hose of the ALT29000001 HYD GRND PWR UNIT3000 to the delivery connector 1008GM with an LOCALLY MANUFACTURED - ADAPTER.
(10) Connect the return hose of the ALT29000001 HYD GRND PWR UNIT3000 to the return line at the LP manifold 1003GM with an LOCALLY MANUFACTURED - ADAPTER.
(11) Put the PLUG-BLANKING in each disconnected line end.

4. Procedure
Subtask 12-36-29-170-061-A

A. Flush the Green hydraulic system.
(1) Operate the hydraulic power cart for 20 s at 20 bar (290.0754 psi).
(2) Stop the hydraulic power cart.

Subtask 12-36-29-960-061-A

B. Replace the LP filter element (Ref. AMM TASK 29-11-44-610-001).

5. Close-up
Subtask 12-36-29-860-085-A

A. Put the system back to the serviceable condition.
(1) Disconnect the pressure hose of the hydraulic power cart and the adaptor from the delivery connector 1008GM.
(2) Disconnect the return hose of the hydraulic power cart and the adaptor from the return line at the LP manifold 1003GM.
(3) Disconnect and remove the union from the pressure and return lines at the THS actuator 9CE.
(4) Remove the hydraulic power cart.
(5) Remove the blanking plugs.
(6) Connect the return line to the LP manifold 1003GM.
(7) Connect the pressure line to the valve block of the THS actuator 9CE.
(8) Connect the return line to the valve block of the THS actuator 9CE.
(9) Safety the connections of the pressure and return lines with corrosion-resistant steel lockwire 0.8 mm (0.032 in) dia.

Subtask 12-36-29-790-061-A

B. Leak Test of the Components which were Disconnected
(1) Pressurize the Green hydraulic system (Ref. AMM TASK 29-10-00-863-001) or (Ref. AMM TASK 29-23-00-863-001).
(2) Make sure that there is no hydraulic fluid leakage.
(3) Depressurize the Green hydraulic system (Ref. AMM TASK 29-10-00-864-001) or (Ref. AMM TASK 29-23-00-864-001).

Subtask 12-36-29-942-100-A

C. Put the aircraft back to its initial configuration.
(1) Remove the containers.
(2) Remove the safety barriers.
(3) Remove the access platform(s).
(4) Remove the WARNING NOTICE(S).

Subtask 12-36-29-410-082-A

D. Close Access
(1) Make sure that the work area is clean and clear of tools and other items.
(2) Close the left MLG door (Ref. AMM TASK 32-12-00-410-001).
(3) Close the access door 312AR.
(4) Close the access door 197CB.
(5) Remove the ground support and maintenance equipment, the special and standard tools and all other items.

[Rev.10 from 2021] 2026.04.02 06:10:39 UTC