Installation of the Asymmetry-Position Pick-Off Unit

TASK 27-51-18-400-001-A
Installation of the Asymmetry-Position Pick-Off Unit

WARNING: MAKE SURE THAT THE FLIGHT CONTROL SAFETY-LOCKS AND THE WARNING NOTICES ARE IN POSITION.

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: BE CAREFUL WHEN YOU USE CONSUMABLE MATERIALS. OBEY THE MATERIAL MANUFACTURER'S INSTRUCTIONS AND YOUR LOCAL REGULATIONS.

CAUTION: BE CAREFUL WHEN YOU DO MAINTENANCE TASKS ON THE WING TRAILING EDGE:

DO NOT CAUSE DAMAGE TO THE ELECTRICAL CABLE RACEWAYS.
DO NOT CAUSE DAMAGE TO THE ELECTRICAL CABLE INSTALLATIONS.
MAKE SURE THAT THE ELECTRICAL CABLES ARE INSTALLED CORRECTLY. INCORRECT INSTALLATION CAN CAUSE DAMAGE.

ZONE: 500
ZONE: 600
FIN: 29CV
FIN: 30CV

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

REFERENCE	QTY	DESIGNATION
No specific	AR	ACCESS PLATFORM 4M (13 FT)
No specific	1	ACCESS PLATFORM 4M (13 FT)-ADJUSTABLE
No specific	1	SAFETY BARRIER(S)
No specific	1	WARNING NOTICE(S)
No specific	Torque wrench: range to between 0.96 and 0.78 m.daN (84.96 and 69.03 lbf.in )
98D27803500002	1	LOCKING TOOL ZERO POS

B. Consumable Materials

REFERENCE	DESIGNATION
(Material No.08BAA9)	Non Aqueous Cleaner-General - -
(Material No.12ACC1)	Corrosion Preventive Compound-Heavy Duty Soft Film -
(Material No.14SBA1)	Textile-Lint free Cotton -

C. Work Zones and Access Panels

ZONE/ACCESS	ZONE DESCRIPTION
500	LEFT WING
600	RIGHT WING
FOR [29CV] (POSITION PICK OFF UNIT)
575FB
FOR [30CV] (POSITION PICK OFF UNIT)
675FB

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 27-50-00-866-009-A	Retraction of the Flaps on the Ground
TASK 27-50-00-866-009-A-01	Retraction of the Flaps/Slats on the Ground
TASK 27-51-00-820-001-A	Manual Adjustment of the Position Pick-Off Units
TASK 27-54-00-710-001-A	Operational Test of the Flap System
TASK 31-32-00-860-006-A	Procedure to Get Access to the SYSTEM REPORT/TEST F/CTL Page
Flap APPU - Detail and Location
Flap APPU - Zero Datum Settings and Locations
FOR [29CV] (POSITION PICK OFF UNIT)
TASK 57-51-37-000-004-A	Removal of the Access Panels 575AB(675AB), 575BB(675BB), 575CB(675CB), 575DB(675DB), 575EB(675EB), 575FB(675FB), 575GB(675GB), 575HB(675HB)
TASK 57-51-37-400-004-A	Installation of the Access Panels 575AB(675AB), 575BB(675BB), 575CB(675CB), 575DB(675DB), 575EB(675EB), 575FB(675FB), 575GB(675GB), 575HB(675HB)
FOR [30CV] (POSITION PICK OFF UNIT)
TASK 57-51-37-000-004-A	Removal of the Access Panels 575AB(675AB), 575BB(675BB), 575CB(675CB), 575DB(675DB), 575EB(675EB), 575FB(675FB), 575GB(675GB), 575HB(675HB)
TASK 57-51-37-400-004-A	Installation of the Access Panels 575AB(675AB), 575BB(675BB), 575CB(675CB), 575DB(675DB), 575EB(675EB), 575FB(675FB), 575GB(675GB), 575HB(675HB)

3. Job Set-up
Subtask 27-51-18-941-057-A

A. Safety Precautions
(1) Make sure that the SAFETY BARRIER(S) are in position.
(2) Make sure that the WARNING NOTICE(S) is in position to tell persons not to operate the flight controls.

Subtask 27-51-18-860-052-B ** ON A/C NOT FOR ALL

B. Aircraft Maintenance Configuration
(1) If you install a new APPU (3):
(a) Make sure that the flaps are fully retracted (Ref. AMM TASK 27-50-00-866-009).
(b) Make sure that the 98D27504005000 PIN RIGGING-FLAPS (TRACK 1) is installed at the track 1 position only.
(2) Make sure that the 98D27803500001 LOCKING TOOL ZERO POS or 98D27803500002 LOCKING TOOL ZERO POS is installed on the flap/slat control-lever quadrant.
(3) Make sure that the ACCESS PLATFORM 4M (13 FT)-ADJUSTABLE is in position:
(a) FOR [29CV] (POSITION PICK OFF UNIT)
below access panel 575FB
(b) FOR [30CV] (POSITION PICK OFF UNIT)
below access panel 675FB.
(4) Make sure that the applicable access panel has been removed:
(a) FOR [29CV] (POSITION PICK OFF UNIT)
remove 575FB (Ref. AMM TASK 57-51-37-000-004)
(b) FOR [30CV] (POSITION PICK OFF UNIT)
remove 675FB (Ref. AMM TASK 57-51-37-000-004).

Subtask 27-51-18-860-052-C ** ON A/C NOT FOR ALL

B. Aircraft Maintenance Configuration
(1) If you install a new APPU (3):
(a) Make sure that the flaps are fully retracted (Ref. AMM TASK 27-50-00-866-009).
(b) Make sure that the 98D27504006000 PIN-RIGGING, FLAPS is installed at the track 1 position only.
(2) Make sure that the 98D27803500001 LOCKING TOOL ZERO POS or 98D27803500002 LOCKING TOOL ZERO POS is installed on the flap/slat control-lever quadrant.
(3) Make sure that the ACCESS PLATFORM 4M (13 FT)-ADJUSTABLE is in position:
(a) FOR [29CV] (POSITION PICK OFF UNIT)
below access panel 575FB
(b) FOR [30CV] (POSITION PICK OFF UNIT)
below access panel 675FB.
(4) Make sure that the applicable access panel has been removed:
(a) FOR [29CV] (POSITION PICK OFF UNIT)
remove 575FB (Ref. AMM TASK 57-51-37-000-004)
(b) FOR [30CV] (POSITION PICK OFF UNIT)
remove 675FB (Ref. AMM TASK 57-51-37-000-004).

Subtask 27-51-18-865-051-A

C. Make sure that this(these) circuit breaker(s) is(are) open, safetied and tagged:

PANEL	DESIGNATION	FIN	LOCATION
** ON A/C NOT FOR ALL
49VU	FLIGHT CONTROLS/FLP/CTL AND MONG/SYS1	6CV	B07
** ON A/C NOT FOR ALL
49VU	FLIGHT CONTROLS/FLP/CTL AND MONG/SYS1	6CV	B02
** ON A/C ALL
121VU	FLIGHT CONTROLS/WTB/FLP/SYS2	12CV	P20
121VU	FLIGHT CONTROLS/FLP/CTL AND/MONG/SYS2	8CV	Q21
122VU	FLIGHT CONTROLS/WTB/FLP/SYS1	10CV	S07

4. Procedure

CAUTION: BE CAREFUL WHEN YOU DO MAINTENANCE TASKS ON THE WING TRAILING EDGE:

DO NOT CAUSE DAMAGE TO THE ELECTRICAL CABLE RACEWAYS.
DO NOT CAUSE DAMAGE TO THE ELECTRICAL CABLE INSTALLATIONS.
MAKE SURE THAT THE ELECTRICAL CABLES ARE INSTALLED CORRECTLY. INCORRECT INSTALLATION CAN CAUSE DAMAGE.

Subtask 27-51-18-420-053-A

A. Preparation for Installation
(1) Clean the component interface and/or the adjacent area with a Textile-Lint free Cotton - (Material No.14SBA1) made moist with Non Aqueous Cleaner-General - - (Material No.08BAA9) .
(2) Clean the interface of the APPU (3), the APPU adaptor assembly (11), the bolts (2) and the washers (1) with Non Aqueous Cleaner-General - - (Material No.08BAA9) .
(3) Examine the APPU (3) and the interface of the APPU adaptor assembly (11) for damage, cracks and corrosion.
(4) Make sure that the parts retained from the removed component are clean and in the correct condition.
(5) Do an inspection of the component interfaces and the adjacent area.
(6) On a new APPU (3) make sure that:

The gear zero marks and the orange zero indicator aligns with their applicable fixed pointers
The marks on the drive shaft align with each other.

Subtask 27-51-18-420-052-A

B. Installation of the Asymmetry-Position Pick-Off Unit

CAUTION: MAKE SURE THAT THE FLAP SYSTEM IS IN THE ZERO POSITION BEFORE YOU INSTALL A NEW APPU. A NEW APPU IS SUPPLIED LOCKED IN THE ELECTRICAL AND MECHANICAL ZERO POSITION.

(1) Make sure the gearbox quill shaft (10) is concentric within the spigot bore of the gearbox (9).
(2) Remove the tie-wrap (6) from behind the locking plate (7).
(3) Put the APPU (3) in position on the gearbox (9). Make sure the shroud slot and the key are correctly aligned.
(4) Engage the APPU drive shaft (8) with the gearbox quill shaft (10).

CAUTION: DO NOT USE THE INSTALLATION BOLTS TO FULLY ENGAGE THE APPU DRIVE IN THE SPIGOT INNER SURFACE. THIS WILL CAUSE:

DAMAGE TO THE APPU
DAMAGE TO THE SPLINES
THE RETAINING PIN TO BREAK.

(a) Use hand pressure and push the APPU (3) fully in position in the gearbox (9).

NOTE: This force must only be sufficient to allow installation of the washers (1) and the bolts (2). The force required will be approximately 3.5 daN (7.90 lbf).

(b) Hold the APPU (3) in this position and install the washers (1) and the bolts (2).
(5) TORQUE the bolts (2) to between 0.96 and 0.78 m.daN (84.96 and 69.03 lbf.in )

.
(6) Apply a layer of Corrosion Preventive Compound-Heavy Duty Soft Film - (Material No.12ACC1) to:

The bolts (2) and the washers (1)
The joint between the APPU (3) and the gearbox (9).

(7) Remove the blanking caps from the plugs (4) and (5) and the connectors A and B.
(8) To electrically connect the APPU:

CAUTION: REFER TO THE MATCH MARKS MADE DURING THE REMOVAL WHEN YOU CONNECT THE ELECTRICAL WIRES. INCORRECT CONNECTION OF THE WIRES WILL CAUSE DAMAGE TO EQUIPMENT.

(a) Connect the plug (4) to the connector A and the plug (5) to the connector B.

Subtask 27-51-18-860-051-B ** ON A/C NOT FOR ALL

C. Aircraft Configuration
(1) Remove the 98D27803500001 LOCKING TOOL ZERO POS or 98D27803500002 LOCKING TOOL ZERO POS from the flap/slat control-lever quadrant.
(2) If a new APPU was installed, remove the 98D27504005000 PIN RIGGING-FLAPS (TRACK 1) from the track 1 position.
(3) Remove the access platform(s).
(4) Make sure that the work area is clean and clear of tools and other items.

Subtask 27-51-18-860-051-C ** ON A/C NOT FOR ALL

C. Aircraft Configuration
(1) Remove the 98D27803500001 LOCKING TOOL ZERO POS or 98D27803500002 LOCKING TOOL ZERO POS from the flap/slat control-lever quadrant.
(2) If a new APPU was installed, remove the 98D27504006000 PIN-RIGGING, FLAPS from the track 1 position.
(3) Remove the access platform(s).
(4) Make sure that the work area is clean and clear of tools and other items.

Subtask 27-51-18-865-052-A

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

PANEL	DESIGNATION	FIN	LOCATION
** ON A/C NOT FOR ALL
49VU	FLIGHT CONTROLS/FLP/CTL AND MONG/SYS1	6CV	B07
** ON A/C NOT FOR ALL
49VU	FLIGHT CONTROLS/FLP/CTL AND MONG/SYS1	6CV	B02
** ON A/C ALL
121VU	FLIGHT CONTROLS/WTB/FLP/SYS2	12CV	P20
121VU	FLIGHT CONTROLS/FLP/CTL AND/MONG/SYS2	8CV	Q21
122VU	FLIGHT CONTROLS/WTB/FLP/SYS1	10CV	S07

Subtask 27-51-18-740-050-A

E. Do a Check of the Position Pick-Off Units (PPUs) on the Centralized Fault Display-System (CFDS)
(1) Energize the aircraft electrical circuits (Ref. AMM TASK 24-41-00-861-002).
(2) Get access to the SYSTEM REPORT/TEST (F/CTL) page on the Multipurpose Control Display-Unit (MCDU) (Ref. AMM TASK 31-32-00-860-006).
(3) Do the check of the flap PPU angles (deg) at the slat/flap control lever position ZERO on the MCDU as follows:

ACTION	RESULT
1.On the MCDU front panel:	On the MCDU display:
Push the line key adjacent to the <SFCC 1 indication.	The SFCC 1 menu comes into view.
Push the NEXT PAGE button.	The MCDU shows the next page of the SFCC 1 menu.
Push the line key adjacent to the SYSTEM DATA FLP> indication.	The SFCC 1 SYSTEM DATA FLAP menu comes into view.
Push the line key adjacent to the <PPU indication.	The PPU DATA page(s) comes into view (Refer to Table 1). NOTE: The difference in the APPU and the FPPU synchro angles must not be more than 1.3 deg (1.3 deg). The difference in the LH APPU and the RH APPU synchro angles must not be more than 0.7 deg (0.7 deg).
Push the line key adjacent to the <RETURN indication again and again, until the CFDS menu comes into view.	The CFDS menu comes into view.

(4) De-energize the aircraft electrical circuits (Ref. AMM TASK 24-41-00-862-002).

+-----------------------------------------------------------------------------+

! !

! SFCC 1 !

! PPU DATA (DEG) !

! DATE:XXX XX UTC:XXXX !

! LH APPU FPPU RH APPU !

! XXX.X XXX.X XXX.X !

! ***HEX ***HEX ***HEX !

!-----------------------------------------------------------------------------!

! OTHER SFCC !

! LH APPU FPPU RH APPU !

! XXX.X XXX.X XXX.X !

! ***HEX ***HEX ***HEX !

!-----------------------------------------------------------------------------!

! <RETURN PRINT> !

!-----------------------------------------------------------------------------!

! Table 1 !

! PPU DATA (DEG) shown on the MCDU at the slat/flap control lever !

! position ZERO. !

+-----------------------------------------------------------------------------+

Subtask 27-51-18-820-050-A

F. Adjustment
(1) Make sure that the difference between:
(a) The LH APPU and the FPPU is 0 +/- 1.3 deg.
(b) The RH APPU and the FPPU is 0 +/- 1.3 deg.
(c) The LH APPU and the RH APPU is 0 +/- 0.7 deg.
(2) If necessary, do the adjustment of the applicable position pick-off unit (Ref. AMM TASK 27-51-00-820-001).

Subtask 27-51-18-710-050-A

G. Test
(1) Install the safety collar on the circuit breakers 10CV and 12CV.
(2) Do an operational test of the flap system (Ref. AMM TASK 27-54-00-710-001).

5. Close-up
Subtask 27-51-18-410-050-A

A. Close Access
(1) Make sure that the work area is clean and clear of tools and other items.
(2) Put the ACCESS PLATFORM 4M (13 FT) in position:
(a) FOR [29CV] (POSITION PICK OFF UNIT)
below the access panel 575FB
(b) FOR [30CV] (POSITION PICK OFF UNIT)
below the access panel 675FB.
(3) Install the applicable access panel:
(a) FOR [29CV] (POSITION PICK OFF UNIT)
install 575FB (Ref. AMM TASK 57-51-37-400-004)
(b) FOR [30CV] (POSITION PICK OFF UNIT)
install 675FB (Ref. AMM TASK 57-51-37-400-004).

Subtask 27-51-18-942-052-A

B. Removal of Equipment
(1) Remove the safety barriers.
(2) Remove the WARNING NOTICE(S).
(3) Remove the access platform(s).
(4) Remove the ground support and maintenance equipment, the special and standard tools and all other items.

[Rev.10 from 2021] 2026.03.31 23:52:35 UTC