Removal of the Trimmable Horizontal Stabilizer (THS) Leading Edge
TASK 55-12-11-000-001-A
Removal of the Trimmable Horizontal Stabilizer (THS) Leading Edge
To get access to the front spar of the spar box.
To replace damaged leading edge sections.
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 55-12-11-860-050-A
[Rev.10 from 2021]
2026.04.01 02:04:44 UTC
Removal of the Trimmable Horizontal Stabilizer (THS) Leading Edge
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.
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.
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.
WARNING:
YOU MUST PUT ON AND ATTACH A SAFETY HARNESS BEFORE YOU START WORK:
- ON THE THS OR IN THE REAR FUSELAGE
- ON TOP OF THE WINGS OR PYLONS.
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:
DO NOT CAUSE DAMAGE TO THE SURFACES. THE COMPONENTS ARE MADE OF CARBONFIBER REINFORCED PLASTIC.
1. Reason for the JobTo get access to the front spar of the spar box.
To replace damaged leading edge sections.
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 | AR | SAFETY CLIP - CIRCUIT BREAKER |
| No specific | AR | WARNING NOTICE(S) |
| 98D27903500000 | 2 | PIN-SIDE STICK LOCKING |
| ZONE/ACCESS | ZONE DESCRIPTION |
|---|---|
| 331 | THS LEADING EDGE |
| 341 | THS LEADING EDGE |
| REFERENCE | DESIGNATION |
|---|---|
| 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 29-10-00-864-003-A | Depressurize the Blue Hydraulic System |
Subtask 55-12-11-860-050-A
A. Depressurize Hydraulic Systems
(1) Make sure that the Green, Yellow and Blue hydraulic systems are depressurized (Ref. AMM TASK 29-10-00-864-001), (Ref. AMM TASK 29-10-00-864-002) and (Ref. AMM TASK 29-10-00-864-003).
Subtask 55-12-11-865-050-A (1) Make sure that the Green, Yellow and Blue hydraulic systems are depressurized (Ref. AMM TASK 29-10-00-864-001), (Ref. AMM TASK 29-10-00-864-002) and (Ref. AMM TASK 29-10-00-864-003).
B. Open, safety and tag this(these) circuit breaker(s):
Subtask 55-12-11-481-050-A | PANEL | DESIGNATION | FIN | LOCATION |
|---|---|---|---|
| ** ON A/C NOT FOR ALL | |||
| 49VU | FLIGHT CONTROLS/THS/ACTR/MOT2 | 19CE2 | B09 |
| ** ON A/C NOT FOR ALL | |||
| 49VU | FLIGHT CONTROLS/THS/ACTR/MOT2 | 19CE2 | B04 |
| ** ON A/C ALL | |||
| 121VU | FLIGHT CONTROLS/THS ACTR/MOT3 | 19CE3 | Q17 |
| 121VU | FLIGHT CONTROLS/THS ACTR/MOT1 | 19CE1 | Q16 |
C. Install Locking Devices
(1) Install the 98D27903500000 PIN-SIDE STICK LOCKING in the CAPT and F/O side stick controllers.
Subtask 55-12-11-941-050-A (1) Install the 98D27903500000 PIN-SIDE STICK LOCKING in the CAPT and F/O side stick controllers.
D. Safety Precautions
(1) Put the WARNING NOTICE(S) in the flight compartment to tell persons not to operate the flight controls.
(2) Put the WARNING NOTICE(S) in position to tell persons not to operate the hydraulic systems.
(3) Put the ACCESS PLATFORM 4M (13 FT) in position at zone 330 for the left hand horizontal stabilizer leading edge and/or zone 340 for the right hand horizontal stabilizer leading edge.
4. Procedure(1) Put the WARNING NOTICE(S) in the flight compartment to tell persons not to operate the flight controls.
(2) Put the WARNING NOTICE(S) in position to tell persons not to operate the hydraulic systems.
(3) Put the ACCESS PLATFORM 4M (13 FT) in position at zone 330 for the left hand horizontal stabilizer leading edge and/or zone 340 for the right hand horizontal stabilizer leading edge.
NOTE: Only the removal of the left hand leading edge is shown. The removal of the right hand leading edge is the same. Identify all hardware for reinstallation.
Subtask 55-12-11-020-058-C A. Removal of Leading Edge
(1) Remove the inboard and the outboard leading edge (2) and (3).
(a) Remove the screws (4), (5) and (6) from the leading edge sections (2) and (3).
(b) Remove the leading edge sections (2) and (3).
(2) Remove the leading edge intersection (1).
(a) Remove the screws (4) from the leading edge intersection (1).
(b) Remove the leading edge intersection (1).
(1) Remove the inboard and the outboard leading edge (2) and (3).
(a) Remove the screws (4), (5) and (6) from the leading edge sections (2) and (3).
(b) Remove the leading edge sections (2) and (3).
(2) Remove the leading edge intersection (1).
(a) Remove the screws (4) from the leading edge intersection (1).
(b) Remove the leading edge intersection (1).
Trimmable Horizontal Stabilizer Leading-Edge