Inspection of the Rudder Yaw Damper Servo-Actuator for Leakage

TASK 27-26-51-200-001-A
Inspection of the Rudder Yaw Damper Servo-Actuator for Leakage

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.

ZONE: 325
FIN: 3CC1
FIN: 3CC2

1. Reason for the Job
Refer to the MPD TASK: 272651-01
INSPECTION OF RUDDER YAW DAMPER SERVO-ACTUATOR FOR LEAKAGE

NOTE: The inspection procedure that follows is only applicable if a yaw damper servo-actuator with the part number SC4700-3 is installed.

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)
98D27207548000	1	PIN-RIGGING

B. Consumable Materials

REFERENCE	DESIGNATION
(Material No.08BAA9)	Non Aqueous Cleaner-General - -
(Material No.14SBA1)	Textile-Lint free Cotton -

C. Work Zones and Access Panels

ZONE/ACCESS	ZONE DESCRIPTION
325	VERTICAL STABILIZER TRAILING EDGE
325BL, 325BR

D. Referenced Information

REFERENCE	DESIGNATION
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 27-26-51-000-001-A	Removal of the Yaw Damper Servo Actuator
TASK 27-26-51-400-001-A	Installation of the Yaw Damper Servo Actuator
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 31-32-00-860-010-A	Procedure to Get Access to the SYSTEM REPORT/TEST NAV Page
TASK 31-60-00-860-001-A	EIS Start Procedure
TASK 31-60-00-860-002-A	EIS Stop Procedure
TASK 34-14-00-740-001-A	Interface Test of the IR
TASK 55-33-13-010-002-A	Opening/Removal of the Trailing Edge Access-Panels of the Vertical Stabilizer
TASK 55-33-13-410-002-A	Closing/Installation of the Trailing Edge Access-Panels of the Vertical Stabilizer
Servo Actuator - Yaw Damper (3CC1,3CC2)

3. Job Set-up
Subtask 27-26-51-010-057-B

A. Get Access
(1) Put the ACCESS PLATFORM 6M (20 FT) - ADJUSTABLE in position.
(2) Open the access panel 325BL and 325BR at the trailing edge of the vertical stabilizer (Ref. AMM TASK 55-33-13-010-002).

Subtask 27-26-51-860-060-A

B. Cleaning and Visual Inspection
(1) Clean the yaw damper servo actuators and the adjacent area with a lint-free cotton cloth Textile-Lint free Cotton - (Material No.14SBA1) and Non Aqueous Cleaner-General - - (Material No.08BAA9) .
(2) Examine the yaw damper servo actuators and the adjacent area for:

damage
corrosion
satisfactory surface protection.

Subtask 27-26-51-860-059-A ** ON A/C NOT FOR ALL

C. Aircraft Maintenance Configuration
(1) Energize the aircraft electrical circuits (Ref. AMM TASK 24-41-00-861-002).
(2) Do the EIS start procedure (ECAM system only) (Ref. AMM TASK 31-60-00-860-001).
(3) Pressurize the aircraft hydraulic systems (Ref. AMM TASK 29-23-00-863-001) (Ref. AMM TASK 29-10-00-863-003).
(4) On the center pedestal, on the ECAM control panel:

Get the F/CTL page.

(5) On the overhead panel, on the ADIRS CDU panel:

Set the OFF/NAV/ATT selector switch related to IR3 to NAV.
Make sure that the OFF/NAV/ATT selector switches related to IR1 and IR2 are in the OFF position.

(6) On the overhead panel, on the FLT CTL panels 23VU and 24VU:

Make sure that the FAC1 and the FAC2 pushbutton switches are pushed (the FAULT and OFF legends are off).

(7) Put the WARNING NOTICE(S) in the flight compartment to tell persons not to operate the flight controls.
(8) Put the WARNING NOTICE(S) in position to tell persons not to operate the Green, the Yellow and the Blue hydraulic systems:

in the cockpit on the hydraulic section 40VU of the overhead panel,
on the ground service panels of the Green, Yellow and Blue hydraulic systems.

Subtask 27-26-51-860-059-B ** ON A/C NOT FOR ALL

Get the F/CTL page.

(5) On the overhead panel, on the ADIRS MSU panel 41VU:

Set the OFF/NAV/ATT selector switch related to IR3 to NAV.
Make sure that the OFF/NAV/ATT selector switches related to IR1 and IR2 are in the OFF position.

(6) On the overhead panel, on the FLT CTL panels 23VU and 24VU:

Make sure that the FAC1 and the FAC2 pushbutton switches are pushed (the FAULT and OFF legends are off).

in the cockpit on the hydraulic section 40VU of the overhead panel,
on the ground service panels of the Green, Yellow and Blue hydraulic systems.

Subtask 27-26-51-865-062-A

D. Make sure that this(these) circuit breaker(s) is(are) closed:

PANEL	DESIGNATION	FIN	LOCATION
** ON A/C NOT FOR ALL
49VU	AUTO FLT/FAC1/28VDC	5CC1	B04
49VU	AUTO FLT/FAC1/26VAC	14CC1	B03
** ON A/C NOT FOR ALL
49VU	AUTO FLT/FAC1/28VDC	5CC1	H10
49VU	AUTO FLT/FAC1/26VAC	14CC1	H09
** ON A/C ALL
121VU	AUTO FLT/FAC2/28VDC	5CC2	M19
121VU	AUTO FLT/FAC2/26VAC	14CC2	M18

4. Procedure
Subtask 27-26-51-710-054-A

A. Check for the External Leakage of the Yaw Damper Servo Actuator

NOTE: This procedure is for the Green hydraulic system. For the Yellow hydraulic system, use the indications between the parentheses.

ACTION	RESULT
1.On the FLT CTL panel 24VU(23VU):
Release the FAC2(FAC1) pushbutton switch.	On this pushbutton switch, the OFF legend comes on.
2.On the center pedestal, on the MCDU2 (or on the L side console, on the MCDU3): Get the SYSTEM REPORT/TEST NAV page (Ref. AMM TASK 31-32-00-860-010).
Push the line key adjacent to the IR3 indication.	The IR3 page comes into view.
Get access to the INTERFACE TEST of the IR3 (Ref. AMM TASK 34-14-00-740-001).
NOTE: For the test below, ignore the warnings and the attitude changes.
3.Push the line key adjacent to the START TEST indication.	The rudder moves to the left, then slowly moves back to zero.
4.Push the line key adjacent to the RETURN (TEST STOP) indication.	The rudder moves to the right, then slowly moves back to zero.
5.On the MCDU2 (or 3): Push the the line key adjacent to the RETURN indication until the CFDS menu page comes into view.	On the MCDU2 (or 3): The CFDS MENU page comes into view.
6.On the FLT CTL panel 24VU(23VU):
Push the FAC2(FAC1) pushbutton switch.	On this pushbutton switch, the OFF legend goes off.

(1) Put the 98D27207548000 PIN-RIGGING (1) in the mixer of the artificial feel unit.
(2) Do a visual check of the yaw damper servo actuators for external leakages.

Subtask 27-26-51-210-058-A

B. Leakage Rates
(1) If the leakage rate is less than 4 drops per minute, no further action is necessary.
(2) If the leakage rate is between 4 and 14 drops drops per minute, replace the yaw damper servo actuator(s) before the next 750 flight hours (Ref. AMM TASK 27-26-51-000-001) and (Ref. AMM TASK 27-26-51-400-001).
(3) If the leakage rate is between 15 and 30 drops drops per minute, replace the yaw damper servo actuator(s) before the next 100 flight hours (Ref. AMM TASK 27-26-51-000-001) and (Ref. AMM TASK 27-26-51-400-001).
(4) If the leakage rate is more than 30 drops per minute, replace the yaw damper servo actuator(s) immediately (Ref. AMM TASK 27-26-51-000-001) and (Ref. AMM TASK 27-26-51-400-001).

5. Close-up
Subtask 27-26-51-410-054-B ** ON A/C NOT FOR ALL

A. Put the aircraft back to the serviceable condition.
(1) On the overhead panel, on the ADIRS CDU panel:

Set the OFF/NAV/ATT selector switch related to IR3 to OFF.

(2) Do the EIS stop procedure (ECAM system only) (Ref. AMM TASK 31-60-00-860-002).
(3) De-energize the aircraft electrical circuits (Ref. AMM TASK 24-41-00-862-002).
(4) Remove the rigging pin (1) from the mixer of the artificial feel unit.
(5) Depressurize the aircraft hydraulic systems (Ref. AMM TASK 29-23-00-864-001) and (Ref. AMM TASK 29-10-00-864-003).
(6) Make sure that the work area is clean and clear of tools and other items.
(7) Close the access panel 325BL and 325BR at the trailing edge of the vertical stabilizer (Ref. AMM TASK 55-33-13-410-002).
(8) Remove the WARNING NOTICE(S).
(9) Remove the access platform(s).

Subtask 27-26-51-410-054-C ** ON A/C NOT FOR ALL

A. Put the aircraft back to the serviceable condition.
(1) On the overhead panel, on the ADIRS MSU panel 41VU:

Set the OFF/NAV/ATT selector switch related to IR3 to OFF.

[Rev.10 from 2021] 2026.03.31 23:49:58 UTC