Check of the Differential-Pressure Indicator and of the Position of the Fluid- Reserve Piston of the Elevator Servo Controls

TASK 27-34-00-220-002-A
Check of the Differential-Pressure Indicator and of the Position of the Fluid- Reserve Piston of the Elevator Servo Controls

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: 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: WHEN YOU DO THIS WORK, ALWAYS PUT ON PROTECTIVE GLOVES, GOGGLES AND PROTECTIVE CLOTHING TO PREVENT INJURY.

ZONE: 334
ZONE: 344
FIN: 34CE1
FIN: 34CE2
FIN: 34CE3
FIN: 34CE4

1. Reason for the Job
Refer to the MPD TASK: 273400-04
CHECK OF THE DIFFERENTIAL PRESSURE INDICATOR AND POSITION OF FLUID RESERVE PISTON OF ELEVATOR SERVO CONTROLS
2. Job Set-up Information
A. Fixtures, Tools, Test and Support Equipment

REFERENCE	QTY	DESIGNATION
No specific	1	ACCESS PLATFORM 6M (20 FT) - ADJUSTABLE
No specific	AR	WARNING NOTICE(S)
0U145914	1	DRAINING TOOL
98D27903500000	2	PIN-SIDE STICK LOCKING

B. Consumable Materials

REFERENCE	DESIGNATION
No specific	lockwire 0.8 mm

C. Work Zones and Access Panels

ZONE/ACCESS	ZONE DESCRIPTION
334	THS TRAILING EDGE
344	THS TRAILING EDGE
334DB, 344DB

D. Expendable Parts

FIG.ITEM	DESIGNATION	IPC-CSN
5	SEAL	AIPC 27-34-51-01-157
9	COTTER PIN	AIPC 27-34-51-01-160

E. 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 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 27-34-51-000-001-A	Removal of the Elevator Servo Control
TASK 27-34-51-400-001-A	Installation of the Elevator Servo Control
TASK 29-10-00-863-003-A	Pressurize the Blue Hydraulic System with a Hydraulic Ground Power-Cart
TASK 29-10-00-863-003-A-01	Pressurize the Blue Hydraulic System with the Blue Electric Pump
TASK 29-10-00-864-003-A	Depressurize the Blue Hydraulic System
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 29-24-00-863-001-A	Pressurize the Yellow Hydraulic System with the Electric Pump
TASK 29-24-00-864-001-A	Depressurize the Yellow Hydraulic System
TASK 55-13-11-000-001-A	Remove/Open of the Trimmable Horizontal Stabilizer (THS) Trailing-Edge Access-Panels
TASK 55-13-11-400-001-A	Install/Close of the Trimmable Horizontal Stabilizer (THS) Trailing-Edge Access-Panels
Differential Pressure Sensor and Drain System
Elevator Servo Control ** ON A/C NOT FOR ALL
Elevator Servo Control ** ON A/C NOT FOR ALL

3. Job Set-up
Subtask 27-34-00-860-062-A

A. Aircraft Maintenance Configuration
(1) Energize the aircraft electrical circuits (Ref. AMM TASK 24-41-00-861-002).
(2) Pressurize the aircraft hydraulic systems (Ref. AMM TASK 29-23-00-863-001) (Ref. AMM TASK 29-24-00-863-001) (Ref. AMM TASK 29-10-00-863-003).
(3) Install the 98D27903500000 PIN-SIDE STICK LOCKING on the CAPT and F/O side sticks.
(4) Put a WARNING NOTICE(S) on the CAPT and F/O side sticks to tell persons not to touch the side sticks.
(5) Put a WARNING NOTICE(S) on the pitch-trim control wheels to tell persons not to use the pitch trim.

Subtask 27-34-00-010-058-A

B. Get Access
(1) Put the ACCESS PLATFORM 6M (20 FT) - ADJUSTABLE in position.
(2) Open the THS trailing edge access panels 334DB 344DB (Ref. AMM TASK 55-13-11-000-001).

4. Procedure
Subtask 27-34-00-210-052-A

A. Check of the Differential-Pressure Indicator and of the Position of the Fluid-Reserve Piston of the Elevator Servo Controls
(1) On each servo control (1), make sure that the indicator of the fluid-reserve (2) piston is in the maximum extended position.
(2) Depressurize the aircraft hydraulic systems (Ref. AMM TASK 29-23-00-864-001) (Ref. AMM TASK 29-24-00-864-001) (Ref. AMM TASK 29-10-00-864-003).
(3) Put the WARNING NOTICE(S) in position to tell persons not to pressurize the hydraulic systems :
(a) In the cockpit, on the HYD section of the overhead panel 40VU.
(b) On the ground service panels of the hydraulic systems.
(4) Remove the protective plug from the differential pressure sensor (3).

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.

(5) Cut and discard the lockwire on the protective plug (7) of the drain system (4).
(6) Remove the cotter pin (9), the washer (8) and the protective plug (7) of the drain system (4).
(7) Remove the obturator (6) and its seal (5).
(8) Install the 0U145914 DRAINING TOOL on the drain system (4).
(9) Drain the fluid reserve (2).

NOTE: When the fluid drains, make sure that the position indicator of the fluid- reserve (2) piston moves continuously to maximum retracted position.
Make sure that it stays in the retracted position.
If not, replace the servo control (1) (Ref. AMM TASK 27-34-51-000-001) and (Ref. AMM TASK 27-34-51-400-001).

(10) Remove the 0U145914 DRAINING TOOL.
(11) Push in the indicator of the differential pressure sensor (3).
(12) Make sure that it stays pushed in.
If not, replace the servo control (1) (Ref. AMM TASK 27-34-51-000-001) (Ref. AMM TASK 27-34-51-400-001).
(13) Pressurize the hydraulic systems (Ref. AMM TASK 29-23-00-863-001) (Ref. AMM TASK 29-24-00-863-001) (Ref. AMM TASK 29-10-00-863-003).
(14) Make sure that:

The indicator of the fluid-reserve (2) piston is in the extended position, and
The indicator of the differential pressure sensor (3) is in the extended position.

If not, replace the servo control (1) (Ref. AMM TASK 27-34-51-000-001) and (Ref. AMM TASK 27-34-51-400-001).
(15) Install the protective plug on the differential pressure sensor (3).
(16) Install the obturator (6) and its seal (5).

NOTE: Make sure that the seal is in good condition. If not, replace the AIPC 27-34-51-01-157 SEAL (5).

(17) Install the protective plug (7) on the drain system (4).
(18) Install the washer (8) and a new AIPC 27-34-51-01-160 COTTER PIN (9).

(19) Secure with the lockwire 0.8 mm the protective plug (7) on the drain system (4).

5. Close-up
Subtask 27-34-00-860-063-A

A. Put the aircraft back to its initial configuration.
(1) Depressurize the hydraulic systems (Ref. AMM TASK 29-23-00-864-001) (Ref. AMM TASK 29-24-00-864-001) (Ref. AMM TASK 29-10-00-864-003).
(2) Make sure that the level of hydraulic fluid in the (Green, Blue and Yellow) reservoirs is correct.
Fill the reservoirs if necessary (Ref. AMM TASK 12-12-29-611-001).
(3) Remove the WARNING NOTICE(S).
(4) Remove the 98D27903500000 PIN-SIDE STICK LOCKING from the CAPT and F/O side sticks.
(5) Make sure that the work area is clean and clear of tools and other items.
(6) De-energize the aircraft electrical circuits (Ref. AMM TASK 24-41-00-862-002).

Subtask 27-34-00-410-058-A

B. Close Access
(1) Close the THS trailing edge access panels 334DB 344DB (Ref. AMM TASK 55-13-11-400-001).
(2) Remove the access platform(s).

[Rev.10 from 2021] 2026.03.31 23:50:12 UTC