Adjustment of the N/WS Zero Position for A/C with N/WS Feedback Sensor-Box P/N E21336000, NLG Centering Cams as Reference

TASK 32-51-00-820-002-A-02
Adjustment of the N/WS Zero Position for A/C with N/WS Feedback Sensor-Box P/N E21336000, NLG Centering Cams as Reference

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.

CAUTION: IF THE SENSOR BOX HAS P/N E21336000, NEVER REMOVE THE SENSOR FROM THE GEARBOX. THE SENSOR AND THE GEARBOX ARE AN ASSEMBLY THAT YOU MUST NOT DISASSEMBLE ON THE AIRCRAFT. IF YOU REMOVE THE SENSOR FROM THE GEARBOX:

YOU WILL CAUSE DAMAGE TO THE SENSOR BOX
THE ADJUSTMENT OF THE SENSOR BOX WILL NO LONGER BE CORRECT.

1. Reason for the Job
Do this procedure when you have a sensor box P/N E21336000 installed on the NLG and when you use the NLG centering cams as reference for the adjustment.
2. Job Set-up Information
A. Fixtures, Tools, Test and Support Equipment

REFERENCE	QTY	DESIGNATION
No specific	AR	SAFETY CLIP - CIRCUIT BREAKER
No specific	AR	SPATULA - NON METALLIC
No specific	AR	VOLTMETER - AC, 0-20 V MIN, 0,001 V, 50 TO 2000 HTZ
No specific	AR	WARNING NOTICE(S)
No specific	Torque wrench: range to between 0.25 and 0.21 m.daN (22.12 and 18.58 lbf.in )
F26792000	1	SENSOR-VOLTAGE TEST
F26792000-1	1	SENSOR-VOLTAGE TEST

B. Consumable Materials

REFERENCE	DESIGNATION
(Material No.06ABF1)	Polysulfide Sealant-Fuel Tank Quick Curing -

C. Referenced Information

REFERENCE	DESIGNATION
TASK 07-11-00-581-003-A	Lifting of the Aircraft at the Forward Jacking Point, MLG Wheels on the Ground
TASK 07-11-00-586-001-A	Lowering of the Aircraft at Forward Jacking Point, MLG Wheels on the Ground
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 29-10-00-864-001-A	Depressurize the Green Hydraulic System
TASK 29-10-00-864-002-A	Depressurize the Yellow Hydraulic System
TASK 32-46-00-740-001-A	BITE Test of the BSCU
Adjustment of the Sensor Box P/N E21336000, NLG cams as reference

3. Job Set-up
Subtask 32-51-00-941-055-A

A. General
(1) Put a WARNING NOTICE(S) in the cockpit to tell persons not to operate the landing gear or the N/WS.
(2) On the panel 400VU, make sure that the L/G normal control lever is in the DOWN position.
(3) On the nose gear leg, on the nose wheel steering deactivation electrical box, make sure that the towing lever is in the normal position (engaged position).
(4) Make sure that the N/WS handwheels and the rudder pedals are in the neutral position.

Subtask 32-51-00-860-069-A ** ON A/C NOT FOR ALL

B. Aircraft Maintenance Configuration
(1) Jack up the front of the aircraft (Ref. AMM TASK 07-11-00-581-003).

NOTE: In the fully extended position of the shock absorber, the NLG is automatically centered (the nose wheel steering is in the zero position).

(2) Make sure that the Green hydraulic system is de-pressurized (Ref. AMM TASK 29-10-00-864-001).
(3) Energize the aircraft electrical circuits (Ref. AMM TASK 24-41-00-861-002).

Subtask 32-51-00-860-069-B ** ON A/C NOT FOR ALL

B. Aircraft Maintenance Configuration
(1) Jack up the front of the aircraft (Ref. AMM TASK 07-11-00-581-003).

NOTE: In the fully extended position of the shock absorber, the NLG is automatically centered (the nose wheel steering is in the zero position).

(2) Make sure that the Yellow hydraulic system is de-pressurized (Ref. AMM TASK 29-10-00-864-002).
(3) Energize the aircraft electrical circuits (Ref. AMM TASK 24-41-00-861-002).

Subtask 32-51-00-865-085-A

C. Open, safety and tag this(these) circuit breaker(s):

PANEL	DESIGNATION	FIN	LOCATION
** ON A/C ALL
121VU	HYDRAULIC/BRAKING AND STEERING/SYS2/CTL	3GG	M35
121VU	HYDRAULIC/BRAKING AND STEERING/SYS1/CTL	1GG	M34

4. Procedure
Subtask 32-51-00-220-055-A

A. Check of the Play on the NLG Centering Cams
(1) Disconnect the connector (4) from the nose-wheel-steering feedback-sensor 3GC (1) (control channel) of the Rotary Variable Differential Transducer (RVDT).
(2) Connect the F26792000 SENSOR-VOLTAGE TEST or F26792000-1 SENSOR-VOLTAGE TEST (3) between the connector (4) and the RVDT 3GC (1).
(3) On panel 121VU, close the circuits breakers 1GG and 3GG.
(4) Connect a VOLTMETER - AC, 0-20 V MIN, 0,001 V, 50 TO 2000 HTZ to the SECONDARY VOLTAGE connections on the F26792000 SENSOR-VOLTAGE TEST or F26792000-1 SENSOR-VOLTAGE TEST.
(5) Do a check of the play on the NLG cams:
(a) On the F26792000 SENSOR-VOLTAGE TEST or F26792000-1 SENSOR-VOLTAGE TEST set the selector switch to U1.
(b) Manually move the wheels in steering mode to the right stop. Record voltage U1.
(c) Manually move the wheels in steering mode to the left stop. Record voltage U1'.
(d) Use the voltages U1 and U1' to calculate the average voltage U1".
(e) Manually move the wheels in steering mode to get voltage U1".

NOTE: The angular travel of the nose wheels includes the NLG centering cam play and the NLG torque-link play.

(6) Do the same procedure for the RVDT 4GC (monitoring channel).

Subtask 32-51-00-820-059-A

YOU WILL CAUSE DAMAGE TO THE SENSOR BOX
THE ADJUSTMENT OF THE SENSOR BOX WILL NO LONGER BE CORRECT.

B. Set the NWS Zero Position

NOTE: When the shock absorber is fully extended, the NLG is automatically in the center position (the nose wheel steering is in the zero position).

NOTE: Do not move the wheels manually in the steering mode when you do the adjustment procedure.

(1) Measure the secondary voltages U1 and U2 for the sensor 3GC
Make sure that :

-------------------------------------

! U1 = U2 plus or minus 20 mV !

-------------------------------------

(2) If U1 is not equal to U2 plus or minus 20 mV, do these steps:
(a) Use a SPATULA - NON METALLIC to remove the sealant:

from the areas identified S.
from the housing of the worm screw (5).

NOTE: Do not cause damage to the surface protections of these parts.

(b) Loosen the screws (2) to release the sensor.
(c) Turn the worm screw (5) to get:

-------------------------------------

! U1 = U2 plus or minus 20 mV !

-------------------------------------

(d) TORQUE the screws (2) to between 0.25 and 0.21 m.daN (22.12 and 18.58 lbf.in )

.
(e) Make sure that U1 = U2 plus or minus 20 mV. If not, do the adjustment again.
(3) On the panel 121VU, open, safety and tag the circuit breakers 1GG and 3GG.
(4) Remove the F26792000 SENSOR-VOLTAGE TEST or F26792000-1 SENSOR-VOLTAGE TEST (3).
(5) Connect the electrical connector (4) to the sensor box (1).
(6) Apply a layer of Polysulfide Sealant-Fuel Tank Quick Curing - (Material No.06ABF1) on the areas identified S.
(7) Fill the housing of the worm screw (5) with Polysulfide Sealant-Fuel Tank Quick Curing - (Material No.06ABF1) .
(8) Do the adjustment procedure again for the sensor 4GC (monitor channel).

Subtask 32-51-00-865-087-A

C. Remove the safety clip(s) and the tag(s) and close this(these) circuit breaker(s):

PANEL	DESIGNATION	FIN	LOCATION
** ON A/C ALL
121VU	HYDRAULIC/BRAKING AND STEERING/SYS2/CTL	3GG	M35
121VU	HYDRAULIC/BRAKING AND STEERING/SYS1/CTL	1GG	M34

5. Close-up
Subtask 32-51-00-581-056-A

A. Lower the aircraft to the ground (Ref. AMM TASK 07-11-00-586-001).

Subtask 32-51-00-740-055-A

B. BITE Test
(1) Do the BITE test of the BSCU (Ref. AMM TASK 32-46-00-740-001).

Subtask 32-51-00-942-062-A

C. Remove the 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 ground support and maintenance equipment, the special and standard tools and all other items.

[Rev.10 from 2021] 2026.04.01 00:51:06 UTC