W DOC AIRBUS | AMM A320F

Detailed Visual Inspection of the Ball-Screw Nut Body, the Screw and the Claw Stops 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

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: BE CAREFUL WHEN YOU USE CONSUMABLE MATERIALS. OBEY THE MATERIAL MANUFACTURER'S INSTRUCTIONS AND YOUR LOCAL REGULATIONS.
ZONE: 310
FIN: 9CE
1. Reason for the Job
Refer to the MPD TASK: 274451-04
DETAILED INSPECTION OF THS ACTUATOR BALL SCREW NUT BODY AND SCREW AND CLAW STOPS
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
1
FLASHLIGHT
No specific
AR
WARNING NOTICE(S)
 B. Consumable Materials
REFERENCE
DESIGNATION
(Material No.08BBB1)
Non Aqueous Cleaner-- Petroleum Based -
 C. Work Zones and Access Panels
ZONE/ACCESS
ZONE DESCRIPTION
310
FUSLG TAIL SECTION AFT OF AFT PRESS BHD
312AR
 D. Referenced Information
REFERENCE
DESIGNATION
TASK 12-22-27-640-003-A
Lubricate THS Actuator Ball Screw Nut
TASK 27-44-51-000-003-A
Removal of the Lower Claw Stop
TASK 27-44-51-400-003-A
Installation of the Lower Claw Stop
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
F Ball Screw Nut, Ball Screw and Claw Stops
F THS Actuator 9CE with the Electrical Load Sensing Device (ELSD) ** ON A/C NOT FOR ALL
F THS Actuator 9CE ** ON A/C NOT FOR ALL
3. Job Set-up
Subtask 27-44-51-010-053-A
A. Get Access
   (1) Put the ACCESS PLATFORM 3M (10 FT)- ADJUSTABLE in position.
   (2) Open the access door 312AR.
   (3) Put the WARNING NOTICE(S) in the cockpit to tell persons not to operate the pitch controls.
4. Procedure
Subtask 27-44-51-220-050-A
A. Inspection
   (1) Carefully examine the ball screw nut (5), the ball screw (7) and the claw stops (4).
   (2) Clean the items that follow with the Non Aqueous Cleaner-- Petroleum Based - (Material No.08BBB1) :
  • The claw stops (4)
  • The ball screw nut (5)
  • The ball screw (7)
  • The nut assembly (8).
   (3) Use a FLASHLIGHT and inspect the claw stops (4) for:
  • Cracks
  • Dents.
  • Claw stop damage or swelling.
NOTE: If you find claw stop damage refer to Vendor Service Bulletin 47145-27-15.
NOTE: For the replacement of the lower claw stop refer to (Ref. AMM TASK 27-44-51-000-003) and (Ref. AMM TASK 27-44-51-400-003).
   (4) Make sure that the claw stops (4) are correctly installed on the ball screw (7):
     (a) Make sure that the screws (15) are correctly installed through the keys (18) in the claw stops (4).
     (b) Make sure that the flange (16) is correctly installed on the claw stop (4) and shows no damage.
     (c) Make sure that the tab washer (19) is correctly safetied on the nut (20) at the lower claw stop (4).
   (5) Use the FLASHLIGHT and examine the ball screw nut (5) for:
  • Cracks
  • Dents
  • Corrosion
  • Satisfactory surface protection.
   (6) Make sure that the ball screw nut (5) is correctly installed in the nut assembly (8):
     (a) Make sure that the grease nipple (17):
  • Is clean
  • Shows no damage
  • Is correctly installed in the fail-safe nut (23).
     (b) Make sure that the ice chippers (21) and (24):
  • Show no damage
  • Are correctly installed on the ball screw (7).
     (c) Make sure that the locking bush (22):
  • Shows no damage
  • Is correctly installed on the ball screw nut (5).
   (7) Use a FLASHLIGHT and examine the ball screw (7) for:
  • Cracks
  • Corrosion
  • Satisfactory surface protection.
NOTE: If you find shiny marks on the ball screw (7), do not replace the THSA as these marks are permitted.
Refer to the Goodrich SB for more data (Ref. SB 47145-27-10).
   (8) Examine the area of the ball screw which you did not examine in step (7):
     (a) Pressurize the Green and Yellow hydraulic systems (Ref. AMM TASK 29-23-00-863-001) and (Ref. AMM TASK 29-24-00-863-001).
     (b) Turn the pitch-trim control wheel in the cockpit and put the THS actuator until you can see the area which you could not see in step (7).
     (c) Do step (7) again for this area.
   (9) Use a FLASHLIGHT and inspect the nut assembly (8) for:
  • Cracks
  • Corrosion
  • Satisfactory surface protection.
   (10) Lubricate the ball screw nut (5) (Ref. AMM TASK 12-22-27-640-003).
   (11) Make sure that the THS actuator is in the zero position.
   (12) Depressurize the Green and Yellow hydraulic systems (Ref. AMM TASK 29-23-00-864-001) and (Ref. AMM TASK 29-24-00-864-001).
5. Close-up
Subtask 27-44-51-410-053-A
A. Close Access
   (1) Make sure that the work area is clean and clear of tools and other items.
   (2) Close the access door 312AR
   (3) Remove the WARNING NOTICE(S).
   (4) Remove the access platform(s).
[Rev.10 from 2021] 2026.03.31 23:51:29 UTC
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