DOC AIRBUS | AMM A320FSpecial Detailed Inspection of THSA (High Time THSA Inspection)
TASK 27-44-51-220-804-A
Special Detailed Inspection of THSA (High Time THSA Inspection)
Refer to the MPD TASK: 274451-13
SPECIAL DETAILED INSPECTION OF THSA (HIGH TIME THSA INSPECTION)
2. Job Set-up Information
A. Fixtures, Tools, Test and Support Equipment
B. Work Zones and Access Panels
C. Referenced Information
3. Job Set-up
Subtask 27-44-51-860-081-A ** ON A/C NOT FOR ALL
Subtask 27-44-51-280-056-A ** ON A/C NOT FOR ALL
Subtask 27-44-51-410-072-A ** ON A/C NOT FOR ALL
[Rev.10 from 2021]
2026.03.31 23:51:35 UTC
Special Detailed Inspection of THSA (High Time THSA Inspection)
WARNING:
PUT THE SAFETY DEVICES AND THE WARNING NOTICES IN POSITION BEFORE YOU START A TASK ON OR NEAR:
1. Reason for the Job- THE FLIGHT CONTROLS
- THE FLIGHT CONTROL SURFACES
- THE LANDING GEAR AND THE RELATED DOORS
- COMPONENTS THAT MOVE.
Refer to the MPD TASK: 274451-13
SPECIAL DETAILED INSPECTION OF THSA (HIGH TIME THSA INSPECTION)
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 | MAT - PROTECTIVE |
| No specific | 1 | WARNING NOTICE(S) |
| 98D27403500000 | 1 | PITCH TRIM CONTROL LOCKING |
| ZONE/ACCESS | ZONE DESCRIPTION |
|---|---|
| 310 | FUSLG TAIL SECTION AFT OF AFT PRESS BHD |
| 312AR |
| REFERENCE | DESIGNATION |
|---|---|
| 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 27-44-51-200-002-A | Inspection of the Magnetic Chip Detector and Boroscope Inspection of the Power Gear of the THS-Actuator |
| TASK 27-44-51-220-001-A | Detailed Visual Inspection of the Ball-Screw Nut Body, the Screw and the Claw Stops of the THS-Actuator |
| TASK 27-44-51-220-002-A | Detailed Inspection of the Upper and Lower THS-Actuator Attachments (Primary and Secondary) |
| TASK 27-44-51-400-001-A | Installation of the Trimmable Horizontal Stabilizer (THS) Actuator |
| TASK 29-10-00-864-001-A | Depressurize the Green Hydraulic System |
| TASK 29-10-00-864-002-A | Depressurize the Yellow Hydraulic System |
Inspection of the THS ActuatorSubtask 27-44-51-860-081-A ** ON A/C NOT FOR ALL
A. Aircraft Maintenance Configuration
(1) Make sure that the aircraft electrical circuits are de-energized
(Ref. AMM TASK 24-41-00-862-002).
(2) Make sure that the hydraulic systems are depressurized
(Ref. AMM TASK 29-10-00-864-001) and (Ref. AMM TASK 29-10-00-864-002).
Subtask 27-44-51-941-078-A ** ON A/C NOT FOR ALL (1) Make sure that the aircraft electrical circuits are de-energized
(Ref. AMM TASK 24-41-00-862-002).
(2) Make sure that the hydraulic systems are depressurized
(Ref. AMM TASK 29-10-00-864-001) and (Ref. AMM TASK 29-10-00-864-002).
B. Safety Precautions
(1) Put the 98D27403500000 PITCH TRIM CONTROL LOCKING on the pitch-trim control-wheel in the flight compartment (Ref. AMM TASK 27-00-00-480-001).
(2) Put a WARNING NOTICE(S) in the flight compartment to tell persons not to operate the pitch controls.
(3) Put the WARNING NOTICE(S) in position to tell persons not to pressurize the Green and Yellow hydraulic systems:
Subtask 27-44-51-010-072-A ** ON A/C NOT FOR ALL (1) Put the 98D27403500000 PITCH TRIM CONTROL LOCKING on the pitch-trim control-wheel in the flight compartment (Ref. AMM TASK 27-00-00-480-001).
(2) Put a WARNING NOTICE(S) in the flight compartment to tell persons not to operate the pitch controls.
(3) Put the WARNING NOTICE(S) in position to tell persons not to pressurize the Green and Yellow hydraulic systems:
- On the overhead panel, on the hydraulic section of HYD/FUEL panel 40VU, and
- On the ground service panels of the Green and Yellow hydraulic systems.
C. 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 Trimmable Horizontal Stabilizer (THS) actuator to prevent damage to the structure.
4. Procedure(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 Trimmable Horizontal Stabilizer (THS) actuator to prevent damage to the structure.
Subtask 27-44-51-280-056-A ** ON A/C NOT FOR ALL
A. Special Detailed Inspection of the Trimmable Horizontal Stabilizer (THS) Actuator
(1) Do the inspection of the magnetic chip detector (Ref. AMM TASK 27-44-51-200-002).
(a) It is not necessary to do the boroscopic inspection of power gear detailed in the above task reference.
(2) Do a detailed visual inspection of the ball-screw and nut (Ref. AMM TASK 27-44-51-220-001).
(a) It is not necessary to do the claw stops inspection in the above task reference.
(3) Do a detailed inspection of the upper and the lower attachments (Ref. AMM TASK 27-44-51-220-002).
(4) If one (or more) of these three detailed inspections is (are) not satisfactory:
(a) Replace the THS actuator before the next flight (Ref. AMM TASK 27-44-51-000-001) and (Ref. AMM TASK 27-44-51-400-001).
5. Close-up(1) Do the inspection of the magnetic chip detector (Ref. AMM TASK 27-44-51-200-002).
(a) It is not necessary to do the boroscopic inspection of power gear detailed in the above task reference.
(2) Do a detailed visual inspection of the ball-screw and nut (Ref. AMM TASK 27-44-51-220-001).
(a) It is not necessary to do the claw stops inspection in the above task reference.
(3) Do a detailed inspection of the upper and the lower attachments (Ref. AMM TASK 27-44-51-220-002).
(4) If one (or more) of these three detailed inspections is (are) not satisfactory:
(a) Replace the THS actuator before the next flight (Ref. AMM TASK 27-44-51-000-001) and (Ref. AMM TASK 27-44-51-400-001).
Subtask 27-44-51-410-072-A ** ON A/C NOT FOR ALL
A. Close Access
(1) Remove the MAT - PROTECTIVE.
(2) Make sure that the work area is clean and clear of tools and other items.
(3) Close access door 312AR.
(4) Remove the access platform(s).
Subtask 27-44-51-942-075-A ** ON A/C NOT FOR ALL (1) Remove the MAT - PROTECTIVE.
(2) Make sure that the work area is clean and clear of tools and other items.
(3) Close access door 312AR.
(4) Remove the access platform(s).
B. Put the aircraft back to its initial configuration.
(1) Remove the 98D27403500000 PITCH TRIM CONTROL LOCKING from the pitch-trim control-wheel in the flight compartment (Ref. AMM TASK 27-00-00-080-001).
(2) Remove the WARNING NOTICE(S).
(1) Remove the 98D27403500000 PITCH TRIM CONTROL LOCKING from the pitch-trim control-wheel in the flight compartment (Ref. AMM TASK 27-00-00-080-001).
(2) Remove the WARNING NOTICE(S).