Detailed Inspection of THSA Upper Attachments for Primary and Secondary Load Path

TASK 27-44-51-220-004-A
Detailed Inspection of THSA Upper Attachments for Primary and Secondary Load Path

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 TRAVEL RANGES OF THE FLIGHT CONTROLS SURFACES ARE CLEAR. MOVEMENT OF FLIGHT CONTROLS CAN CAUSE INJURY TO PERSONS AND/OR DAMAGE TO EQUIPMENT.

CAUTION: ALWAYS OBEY THE PRECAUTIONS THAT FOLLOW TO KEEP ELECTRICAL WIRING IN A SATISFACTORY CONDITION (ELECTRICALLY AND MECHANICALLY SERVICEABLE). WHEN YOU DO MAINTENANCE WORK, REPAIRS OR MODIFICATIONS, ALWAYS KEEP ELECTRICAL WIRING, COMPONENTS AND THE WORK AREA AS CLEAN AS POSSIBLE. TO DO THIS:

PUT PROTECTION, SUCH AS PLASTIC SHEETING, CLOTHS, ETC. AS NECESSARY ON WIRING AND COMPONENTS.
REGULARLY REMOVE ALL SHAVINGS, UNWANTED MATERIAL AND OTHER CONTAMINATION

THESE PRECAUTIONS WILL DECREASE THE RISK OF CONTAMINATION AND DAMAGE TO THE ELECTRICAL WIRING INSTALLATION. IF THERE IS CONTAMINATION, REFER TO ESPM 20-55-00.

ZONE: 310
FIN: 9CE

1. Reason for the Job
Refer to the MPD TASK: 274451-11.
DETAILED INSPECTION OF THSA UPPER ATTACHMENTS FOR PRIMARY AND SECONDARY LOAD PATH
2. Job Set-up Information
A. Fixtures, Tools, Test and Support Equipment

REFERENCE	QTY	DESIGNATION
No specific	1	ACCESS PLATFORM 3M (10 FT)- ADJUSTABLE
No specific	AR	FLASHLIGHT
No specific	AR	MAT - PROTECTIVE
No specific	AR	MIRROR - INSPECTION, FLEXIBLE
No specific	1	RULER 150 MM (6 IN) - METALLIC
No specific	AR	SAFETY CLIP - CIRCUIT BREAKER
No specific	1	WARNING NOTICE(S)
98D27403500000	1	PITCH TRIM CONTROL LOCKING

B. Work Zones and Access Panels

ZONE/ACCESS	ZONE DESCRIPTION
310	FUSLG TAIL SECTION AFT OF AFT PRESS BHD
312AR

C. 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 27-00-00-080-001-A	Removal of the Pitch-Trim Control Locking Tool (98D27403500000)
TASK 27-00-00-480-001-A	Installation of the Pitch-Trim Control Locking Tool (98D27403500000)
TASK 27-44-51-000-001-A	Removal of the Trimmable Horizontal Stabilizer (THS) Actuator
TASK 27-44-51-400-001-A	Installation of the Trimmable Horizontal Stabilizer (THS) Actuator
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 31-60-00-860-001-A	EIS Start Procedure
TASK 31-60-00-860-002-A	EIS Stop Procedure
DETAILED INSPECTION OF THE TIE-ROD SPHERE
DETAILED INSPECTION OF THE UPPER THS-ACTUATOR ATTACHMENT

3. Job Set-up
Subtask 27-44-51-860-068-A

A. Aircraft Maintenance Configuration
(1) Energize the aircraft electrical circuits
(Ref. AMM TASK 24-41-00-861-002).
(2) On the overhead panel, on FLT CTL panel 23VU, make sure that the ELAC 1 and SEC 1 pushbutton switches are pushed (the OFF and FAULT legends are off).
(3) On the overhead panel, on FLT CTL panel 24VU, make sure that the ELAC 2 and SEC 2 pushbutton switches are pushed (the OFF and FAULT legends are off).
(4) Do the Electronic Instrument System (EIS) start procedure (Ref. AMM TASK 31-60-00-860-001).
(5) Pressurize the Green and Yellow hydraulic systems.
(Ref. AMM TASK 29-23-00-863-001) and (Ref. AMM TASK 29-24-00-863-001).
(6) On the center pedestal, on the ECAM control panel, push the F/CTL pushbutton switch (on the lower ECAM display unit, the F/CTL page comes into view).
(7) On the center pedestal, turn the pitch-trim control wheels to the 0 degrees position.
(8) Depressurize the Green and Yellow hydraulic systems.
(Ref. AMM TASK 29-23-00-864-001) and (Ref. AMM TASK 29-24-00-864-001).
(9) Do the EIS stop procedure
(Ref. AMM TASK 31-60-00-860-002).
(10) De-energize the aircraft electrical circuits
(Ref. AMM TASK 24-41-00-862-002).

Subtask 27-44-51-941-079-A

B. Safety Precautions
(1) In the cockpit, put the 98D27403500000 PITCH TRIM CONTROL LOCKING on the pitch trim control-wheel (Ref. AMM TASK 27-00-00-480-001).
(2) In the cockpit, put the WARNING NOTICE(S) in position to tell persons not to operate the pitch trim controls.
(3) Put the WARNING NOTICE(S) in position to tell persons not to pressurize the Green, Yellow and Blue hydraulic systems:

In the cockpit, on the overhead panel, on the hydraulic section of HYD/FUEL panel 40VU, and
On the ground service panels of the Green, Yellow and Blue hydraulic systems.

Subtask 27-44-51-865-081-A

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

PANEL	DESIGNATION	FIN	LOCATION
** ON A/C NOT FOR ALL
49VU	FLIGHT CONTROLS/ELAC1/NORM/SPLY	15CE1	B11
49VU	FLIGHT CONTROLS/THS/ACTR/MOT2	19CE2	B09
** ON A/C NOT FOR ALL
49VU	FLIGHT CONTROLS/ELAC1/NORM/SPLY	15CE1	B06
49VU	FLIGHT CONTROLS/THS/ACTR/MOT2	19CE2	B04
** ON A/C ALL
105VU	FLT CTL/ELAC1/STBY SPLY	16CE1	A01
121VU	FLIGHT CONTROLS/THS ACTR/MOT3	19CE3	Q17
121VU	FLIGHT CONTROLS/THS ACTR/MOT1	19CE1	Q16

Subtask 27-44-51-010-066-A

D. Get Access
(1) Put the ACCESS PLATFORM 3M (10 FT)- ADJUSTABLE in position below access door 312AR.
(2) Open access door 312AR.
(3) Put the MAT - PROTECTIVE in the area of the THS actuator to prevent damage to the structure.

4. Procedure
Subtask 27-44-51-220-059-A

A. General Visual Inspection of the THS Actuator Upper-Gimbal and the No-Back Housing Yoke-Structure

DETAILED INSPECTION OF THE TIE-ROD SPHERE

(1) Do not clean the attachments before you do this inspection.
(2) Use the MIRROR - INSPECTION, FLEXIBLE and the FLASHLIGHT to do this inspection.
(a) Make sure that the items are correctly installed and that there are no cracks or other signs of damage on these items:

The upper gimbal,
The no-back housing yoke.

1 If you find cracks and/or signs of damage:
a Replace the THS actuator (Ref. AMM TASK 27-44-51-000-001) and (Ref. AMM TASK 27-44-51-400-001).
b Do the general visual inspection of the THS actuator upper-gimbal and the no-back housing yoke-structure, refer to Para. 4.A.
2 If you do not find cracks and/or signs of damage:
a Continue the procedure to do the detailed inspection of the tie-rod sphere.

Subtask 27-44-51-220-071-A

B. Detailed Inspection of the Tie-Rod Sphere

DETAILED INSPECTION OF THE TIE-ROD SPHERE

(1) Use the MIRROR - INSPECTION, FLEXIBLE and the FLASHLIGHT to do a check for metal particles on the items that follow:

The spherical bearing,
The base of the tie-rod sphere.

(2) If you find metal particles on the base of the tie-rod sphere:
(a) Contact AIRBUS for more instructions.
(3) If you do not find metal particles on the base of the tie-rod sphere:
(a) Continue the procedure to do the detailed inspection of the upper attachment.

Subtask 27-44-51-220-072-A

C. Detailed Inspection of the primary Upper Attachment

DETAILED INSPECTION OF THE UPPER THS-ACTUATOR ATTACHMENT

(1) Use the MIRROR - INSPECTION, FLEXIBLE and the FLASHLIGHT to do the detailed inspection of the upper attachment.
(a) Make sure that the spherical bearings, bushes, locking washers, retainer nuts, attaching bolts, washers and (if applicable) shim(s) are correctly installed.

CAUTION: MAKE SURE THAT THE SLIDING BUSHES ARE CORRECTLY INSTALLED. IF THEY ARE NOT CORRECTLY INSTALLED, DAMAGE TO THE UPPER THSA ATTACHMENT CAN OCCUR.

(b) Make sure that the sliding bushes are correctly installed:
1

DETAILED INSPECTION OF THE UPPER THS-ACTUATOR ATTACHMENT

2 Make sure that the measured values are between 6 mm (0.24 in.) and 7.5 mm (0.30 in.).

NOTE: The measurement can be done from the radius on the two sides of the bolts.

a If the measured values is less than 6 mm (0.24 in.) or more than 7.5 mm (0.30 in.):

Contact AIRBUS for more instructions.

(c) Make sure that the attaching bolts are safetied to each other with the lockwires.
1 Make sure that the washers and (if applicable) the shim(s) fill the spaces between the flanges of the bolts and the retainer nuts.
(d) Do a detailed inspection of the attachment parts of the primary upper attachment to make sure that they are correctly installed:
1 If you find an incorrect installation:
a Contact AIRBUS for more instructions.

Subtask 27-44-51-220-075-A ** ON A/C NOT FOR ALL

DETAILED INSPECTION OF THE UPPER THS-ACTUATOR ATTACHMENT ** ON A/C NOT FOR ALL

(1) Use the MIRROR - INSPECTION, FLEXIBLE and the FLASHLIGHT to do the detailed inspection of the upper attachment.
(a) Do a detailed inspection of the attachment parts of the secondary upper attachment to make sure that they are correctly installed:
1 If you find an incorrect installation:
a Contact AIRBUS for more instructions.

Subtask 27-44-51-220-075-B ** ON A/C NOT FOR ALL

DETAILED INSPECTION OF THE UPPER THS-ACTUATOR ATTACHMENT

(1) Use the MIRROR - INSPECTION, FLEXIBLE and the FLASHLIGHT to do the detailed inspection of the upper attachment.
(a) Make sure that the nuts, locking washers and springboxes are correctly installed:
1 Make sure that the four teeth of each locking washer are bent.
(b) Do a detailed inspection of the attachment parts of the secondary upper attachment to make sure that they are correctly installed:
1 If you find an incorrect installation:
a Contact AIRBUS for more instructions.

5. Close-up
Subtask 27-44-51-410-065-A

A. Close Access
(1) Make sure that the work area is clean and clear of tools and other items.
(2) Remove all the fixtures, tools, test and support equipment used during this procedure.
(3) Remove the MAT - PROTECTIVE.
(4) Close access door 312AR.
(5) Remove the access platform(s).

Subtask 27-44-51-865-085-A

B. 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/ELAC1/NORM/SPLY	15CE1	B11
49VU	FLIGHT CONTROLS/THS/ACTR/MOT2	19CE2	B09
** ON A/C NOT FOR ALL
49VU	FLIGHT CONTROLS/ELAC1/NORM/SPLY	15CE1	B06
49VU	FLIGHT CONTROLS/THS/ACTR/MOT2	19CE2	B04
** ON A/C ALL
105VU	FLT CTL/ELAC1/STBY SPLY	16CE1	A01
121VU	FLIGHT CONTROLS/THS ACTR/MOT3	19CE3	Q17
121VU	FLIGHT CONTROLS/THS ACTR/MOT1	19CE1	Q16

Subtask 27-44-51-860-082-A

C. Put the aircraft back to its initial configuration.
(1) Remove the WARNING NOTICE(S).
(2) Remove the 98D27403500000 PITCH TRIM CONTROL LOCKING (Ref. AMM TASK 27-00-00-080-001).
(3) After maintenance, put the THS actuator back to the initial condition.

[Rev.10 from 2021] 2026.03.31 23:51:33 UTC