Check of the Oscillations of the Servo-Control of the Rudder

TASK 27-24-00-200-802-A
Check of the Oscillations of the Servo-Control of the Rudder

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.

FIN: 1025GM
FIN: 2025GM
FIN: 3025GM

1. Reason for the Job
Self explanatory
2. Job Set-up Information
A. Fixtures, Tools, Test and Support Equipment

REFERENCE	QTY	DESIGNATION
No specific	1	ACCESS PLATFORM 10M (33 FT) - ADJUSTABLE
98D27303003001	1	CHECK TOOL (ANALOG)-AILERON,ELEVATOR,RUDDER
98D27303022000	1	TOOL CHECK - DIGITAL, AILERON ELEVATOR RUDDER

B. Referenced Information

REFERENCE	DESIGNATION
TASK 22-66-34-000-002-A	Removal of the Flight Augmentation Computer (FAC)
TASK 22-66-34-400-002-A	Installation of the Flight Augmentation Computer (FAC)
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 27-22-51-000-001-A	Removal of the Rudder Trim Actuator
TASK 27-22-51-400-001-A	Installation of the Rudder Trim Actuator
TASK 27-26-51-000-001-A	Removal of the Yaw Damper Servo Actuator
TASK 27-26-51-000-002-A	Removal of the Servovalve
TASK 27-26-51-400-001-A	Installation of the Yaw Damper Servo Actuator
TASK 27-26-51-400-002-A	Installation of the Servovalve
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 29-10-00-864-002-A	Depressurize the Yellow Hydraulic System
TASK 29-23-00-860-001-A	Disconnection of the Isolation Coupling of the Power Transfer Unit (PTU)
TASK 29-23-00-864-001-A	Depressurize the Green and Yellow Hydraulic Systems after Operation of the PTU
ASM 226803

3. Job Set-up
Subtask 27-24-00-860-068-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 29-23-00-860-001) (Ref. AMM TASK 29-10-00-863-003).
(3) On the overhead panel, on FLT CTL panels 23VU and 24VU:

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

Subtask 27-24-00-480-056-A

B. Installation of the Tools
(1) Put the ACCESS PLATFORM 10M (33 FT) - ADJUSTABLE in position below zone 320.
(2) Install the 98D27303003001 CHECK TOOL (ANALOG)-AILERON,ELEVATOR,RUDDER or 98D27303022000 TOOL CHECK - DIGITAL, AILERON ELEVATOR RUDDER on the wing structure near the rudder.
(3) Put the pointer of the 98D27303003001 CHECK TOOL (ANALOG)-AILERON,ELEVATOR,RUDDER or 98D27303022000 TOOL CHECK - DIGITAL, AILERON ELEVATOR RUDDER at the trailing edge of the rudder.

4. Procedure
Subtask 27-24-00-220-061-A

A. Check of the Oscillations of the Servo Control of the Rudder
(1) On the overhead panel, on FLT CTL panel 24VU, release the FAC2 pushbutton switch (the OFF legend comes on).
(2) On the dial indicator, measure the amplitude of the oscillations.
(a) If the amplitude is more than 2.8 mm (0.01102 in.):

Replace the servovalve of yaw damper 1 (Ref. AMM TASK 27-26-51-000-002) (Ref. AMM TASK 27-26-51-400-002).

(b) If the fault continues:

Replace FAC1 (1CC1) (Ref. AMM TASK 22-66-34-000-002) (Ref. AMM TASK 22-66-34-400-002).

Pin A/A2 and pin A/X2 of relay 7CC1
Pin A/A2 of relay 7CC1 and circuit breaker 5CC1
Pin A/A1 of relay 7CC1 and pin B/T of the rudder trim actuator
Pin B/S of the rudder trim actuator (10CC) and the ground terminal
Pin B/W of the rudder trim actuator (10CC) and the ground terminal
Pin A/X1 of relay 7CC1 and pin AE/11C of FAC1
Pin AB/12E of FAC1 and pin B/P of the rudder trim actuator (10CC)
Pin AB/12F of FAC1 and pin B/R of the rudder trim actuator (10CC)
Pin B/B of the rudder trim actuator (10CC) and the ground terminal
Pin AB/6E of FAC1 and pin B/E of the rudder trim actuator (10CC)
Pin AB/6F of FAC1 and pin B/F of the rudder trim actuator (10CC)
Pin AB/7E of FAC1 and pin B/C of the rudder trim actuator (10CC)
Pin AB/7F of FAC1 and pin B/D of the rudder trim actuator (10CC)
Pin AE/6E of FAC1 and pin A/L of the rudder trim actuator (10CC)
Pin AE/6F of FAC1 and pin A/M of the rudder trim actuator (10CC)
Pin AE/7E of FAC1 and pin A/J of the rudder trim actuator (10CC)
Pin AE/7F of FAC1 and pin A/K of the rudder trim actuator (10CC)
Pin A/H of the rudder trim actuator (10CC) and the ground terminal
Pin AB/11C of FAC1 and pin A/V of the rudder trim actuator (10CC)
Pin B/X of the rudder trim actuator (10CC) and the ground terminal
Pin AE/4J of FAC1 and pin B/N of the rudder trim actuator (10CC)
ASM 226803.

(d) If the fault continues:

Replace the ACTUATOR-RUDDER TRIM (10CC) (Ref. AMM TASK 27-22-51-000-001) (Ref. AMM TASK 27-22-51-400-001).

(e) If the fault continues:

Replace the SERVO ACTR-YAW DAMPER 1 (3CC1) (Ref. AMM TASK 27-26-51-000-001) (Ref. AMM TASK 27-26-51-400-001).

(3) On the overhead panel, on FLT CTL panel 24VU, push the FAC2 pushbutton switch (the OFF legend goes off).
(4) On the overhead panel, on FLT CTL panel 23VU, release the FAC1 pushbutton switch (the OFF legend comes on).
(5) On the dial indicator, measure the amplitude of the oscillations.
(a) If the amplitude is more than 2.8 mm (0.01102 in.):

Replace the servovalve of yaw damper 2 (Ref. AMM TASK 27-26-51-000-002) (Ref. AMM TASK 27-26-51-400-002).

(b) If the fault continues:

Replace FAC2 (1CC2) (Ref. AMM TASK 22-66-34-000-002) (Ref. AMM TASK 22-66-34-400-002).

Pin A/A2 and pin A/X2 of relay 7CC2
Pin A/A2 of relay 7CC2 and circuit breaker 5CC2
Pin A/A1 of relay 7CC2 and pin A/T of the rudder trim actuator
Pin A/S of the rudder trim actuator (10CC) and the ground terminal
Pin A/W of the rudder trim actuator (10CC) and the ground terminal
Pin A/X1 of relay 7CC2 and pin AE/11C of FAC2
Pin AB/12E of FAC2 and pin A/P of the rudder trim actuator (10CC)
Pin AB/12F of FAC2 and pin A/R of the rudder trim actuator (10CC)
Pin A/B of the rudder trim actuator (10CC) and the ground terminal
Pin AB/6E of FAC2 and pin A/E of the rudder trim actuator (10CC)
Pin AB/6F of FAC2 and pin A/F of the rudder trim actuator (10CC)
Pin AB/7E of FAC2 and pin A/C of the rudder trim actuator (10CC)
Pin AB/7F of FAC2 and pin A/D of the rudder trim actuator (10CC)
Pin AE/6E of FAC2 and pin B/L of the rudder trim actuator (10CC)
Pin AE/6F of FAC2 and pin B/M of the rudder trim actuator (10CC)
Pin AE/7E of FAC2 and pin B/J of the rudder trim actuator (10CC)
Pin AE/7F of FAC2 and pin B/K of the rudder trim actuator (10CC)
Pin B/H of the rudder trim actuator (10CC) and the ground terminal
Pin AB/11C of FAC2 and pin B/V of the rudder trim actuator (10CC)
Pin A/X of the rudder trim actuator (10CC) and the ground terminal
Pin AE/4J of FAC2 and pin A/N of the rudder trim actuator (10CC)
ASM 226803.

(d) If the fault continues:

Replace the SERVO ACTR-YAW DAMPER 2 (3CC2) (Ref. AMM TASK 27-26-51-000-001) (Ref. AMM TASK 27-26-51-400-001).

5. Close-up
Subtask 27-24-00-080-056-A

A. Removal of the Tools
(1) Remove the 98D27303003001 CHECK TOOL (ANALOG)-AILERON,ELEVATOR,RUDDER or 98D27303022000 TOOL CHECK - DIGITAL, AILERON ELEVATOR RUDDER.

Subtask 27-24-00-860-069-A

B. Put the aircraft back to its initial configuration.
(1) On the overhead panel, on the FLT CTL panel 23VU, push the FAC1 pushbutton switch (the OFF legend goes off).
(2) Depressurize the aircraft hydraulic systems
(Ref. AMM TASK 29-23-00-864-001) (Ref. AMM TASK 29-10-00-864-002).
(3) De-energize the aircraft electrical circuits
(Ref. AMM TASK 24-41-00-862-002).

Subtask 27-24-00-942-057-A

C. Remove the maintenance equipment.
(1) Make sure that the work area is clean and clear of tools and other items.
(2) Remove the access platform(s).

[Rev.10 from 2021] 2026.03.31 23:49:25 UTC