Detailed Visual Inspection of the Transmission Assembly

TASK 27-54-00-200-001-A
Detailed Visual Inspection of the Transmission Assembly

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.

1. Reason for the Job
Refer to the MPD TASK: 275400-01
DETAILED INSPECTION OF TRANSMISSION ASSY
2. Job Set-up Information
A. Fixtures, Tools, Test and Support Equipment

REFERENCE	QTY	DESIGNATION
No specific	1	ACCESS PLATFORM 4M (13 FT)-ADJUSTABLE
No specific	1	FLASHLIGHT
No specific	1	MIRROR - INSPECTION, FLEXIBLE
No specific	AR	SAFETY BARRIER(S)
No specific	AR	SAFETY CLIP - CIRCUIT BREAKER
No specific	AR	WARNING NOTICE(S)
460005835	2	SLEEVE - GROUND LOCK

B. Consumable Materials

REFERENCE	DESIGNATION
(Material No.12ACC1)	Corrosion Preventive Compound-Heavy Duty Soft Film -

C. Work Zones and Access Panels

ZONE/ACCESS	ZONE DESCRIPTION
571AB, 573AB, 573BB, 573CB, 575AB, 575BB, 575CB, 575DB, 575EB, 575FB, 575GB, 671AB, 673AB, 673BB, 673CB, 675AB, 675BB, 675CB, 675DB, 675EB, 675FB, 675GB

D. Referenced Information

REFERENCE	DESIGNATION
TASK 27-00-00-080-002-A	Removal of the Flap/Slat Control-Lever Locking Tool (98D27803000000)
TASK 27-50-00-866-008-A	Extension of the Flaps on the Ground
TASK 27-50-00-866-008-A-01	Extension of the Flaps/Slats on the Ground
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 27-54-00-612-001-A	Check of the Flap Rotary Actuator for Serviceable Condition (After Leakage)
TASK 27-54-44-000-001-A	Removal of the Steady Bearings
TASK 27-54-44-000-002-A	Removal of the Steady Bearings
TASK 27-54-44-400-001-A	Installation of the Steady Bearings
TASK 27-54-44-400-002-A	Installation of the Steady Bearings
TASK 27-54-46-000-001-A	Removal of the Nos 2, 3 and 4 Flap Carriages
TASK 27-54-46-000-002-A	Removal of Flap Carriage 1
TASK 27-54-46-400-001-A	Installation of the Nos 2, 3 and 4 Flap Carriages
TASK 27-54-46-400-002-A	Installation of Flap Carriage 1
TASK 27-54-47-000-001-A	Removal of the Line Gearbox
TASK 27-54-47-400-001-A	Installation of the Line Gearbox
TASK 27-54-48-000-001-A	Removal of the Bevel Gearbox
TASK 27-54-48-400-001-A	Installation of the Bevel Gearbox
TASK 27-54-49-000-001-A	Removal of the Flap Track 1 Actuator
TASK 27-54-49-000-002-A	Removal of the Flap Track 2 Actuator
TASK 27-54-49-000-003-A	Removal of the Flap Track 3 Actuator
TASK 27-54-49-000-004-A	Removal of the Flap Track 4 Actuator
TASK 27-54-49-400-001-A	Installation of the Flap Track 1 Actuator
TASK 27-54-49-400-002-A	Installation of the Flap Track 2 Actuator
TASK 27-54-49-400-003-A	Installation of the Flap Track 3 Actuator
TASK 27-54-49-400-004-A	Installation of the Flap Track 4 Actuator
TASK 27-54-51-000-001-A	Removal of the Power Control Unit of the Flap System
TASK 27-54-51-400-001-A	Installation of the Power Control Unit of the Flap System
TASK 27-54-55-000-001-A	Removal of the Flap-Actuator Lever Assembly - Tracks 1 and 2
TASK 27-54-55-000-002-A	Removal of the Flap-Actuator Lever Assembly - Track 3
TASK 27-54-55-000-003-A	Removal of the Flap-Actuator Lever Assembly - Track 4
TASK 27-54-55-400-001-A	Installation of the Flap-Actuator Lever Assembly - Tracks 1 and 2
TASK 27-54-55-400-002-A	Installation of the Flap-Actuator Lever Assembly - Track 3
TASK 27-54-55-400-003-A	Installation of the Flap-Actuator Lever Assembly - Track 4
TASK 32-00-00-481-001-A	Installation of the Safety Devices on the Landing Gears
TASK 32-12-00-010-001-A	Open the Main Gear Doors for Access
TASK 32-12-00-410-001-A	Close the Main Gear Doors after Access
TASK 57-51-37-000-002-A	Removal of the Access Panels 571AB(671AB), 573AB(673AB), 573BB(673BB), 573CB(673CB), 573EB(673EB)
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 57-51-37-400-002-A	Installation of the Access Panels 571AB(671AB), 573AB(673AB), 573BB(673BB), 573CB(673CB), 573EB(673EB)
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)
Flap Transmission - Access Panels
Flap System - Component Location ** ON A/C NOT FOR ALL
Flap System - Component Location ** ON A/C NOT FOR ALL
Steady Bearings and Torque Shaft - Component Location ** ON A/C NOT FOR ALL
Steady Bearings and Torque Shaft - Component Location ** ON A/C NOT FOR ALL

3. Job Set-up
Subtask 27-54-00-941-052-A

A. Safety Precautions
(1) Make sure that the ground safety locks are installed on the landing gear (Ref. AMM TASK 32-00-00-481-001).
(2) Put the WARNING NOTICE(S) in position to tell persons not to pressurize the hydraulic systems.
(3) Put a WARNING NOTICE(S) in position to tell persons not to operate the flight controls.
(4) Put a WARNING NOTICE(S) in position to tell persons not to operate the landing gear doors.
(5) As necessary, use the applicable SAFETY BARRIERS, specified by the operator's instructions and your local regulations.

Subtask 27-54-00-860-059-A

B. Aircraft Maintenance Configuration

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.

(1) Extend the flaps fully (Ref. AMM TASK 27-50-00-866-008).
(2) Make sure that the 98D27803000000 LOCKING TOOL-FLAP SLAT LEVER,INT. POSITION is installed on the flap/slat control lever.

Subtask 27-54-00-865-053-A

C. Open, safety and tag 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/FLP/CTL AND/MONG/SYS2	8CV	Q21

Subtask 27-54-00-010-051-A

D. Get Access

Flap Transmission - Access Panels

(1) Put the ACCESS PLATFORM 4M (13 FT)-ADJUSTABLE in position below the applicable wing.
(2) Open the MLG doors (Ref. AMM TASK 32-12-00-010-001).
(3) Install the 460005835 SLEEVE - GROUND LOCK on each MLG door actuating cylinder.
(4) Remove the access panels:
(a) For the LH wing, remove the following panels:

(b) For the RH wing, remove the following panels:

4. Procedure
Subtask 27-54-00-210-050-B

A. Inspection

Flap System - Component Location ** ON A/C NOT FOR ALL

Steady Bearings and Torque Shaft - Component Location ** ON A/C NOT FOR ALL

(1) Examine the Power Control Unit (PCU):
(a) Make sure that the PCU is correctly installed.
(b) Use a FLASHLIGHT and a MIRROR - INSPECTION, FLEXIBLE to examine the external surfaces of the PCU for:

Cracks
Corrosion
Signs of leakage
Satisfactory surface protection.

(c) If you find damage, replace the defective PCU,
(Ref. AMM TASK 27-54-51-000-001) and (Ref. AMM TASK 27-54-51-400-001).
(d) Make sure that the Line Replaceable Units (LRU) are correctly installed. The LRUs are the:

Two valve blocks
Two inlet filters
Six solenoid valves
Two hydraulic motors
Two Pressure-Off Brakes
Feedback Position Pick-off Unit
Instrumentation Position Pick-off Unit.

(2) Examine the torque shaft assemblies:
(a) Make sure that the torque shaft assemblies are correctly installed and that the retainer springs safety the pins correctly.
(b) Use a FLASHLIGHT and a MIRROR - INSPECTION, FLEXIBLE to examine the torque shafts and the input joints for:

Stress
Distortion
Dents
Cracks
Corrosion
Satisfactory surface protection.

(c) Make sure that the connections between the torque shafts and the input joints are tight.
(d) Do an inspection of the flange bolts for corrosion.
If you do not find corrosion, apply a new layer of the Corrosion Preventive Compound-Heavy Duty Soft Film - (Material No.12ACC1) on the flange bolts.
(e) If you find damage, replace the defective torque shaft assembly,
refer to the related task in the topic 27-54-45-04.
(3) Examine each steady bearing assembly:
(a) Make sure that each steady bearing assembly is correctly installed.
(b) Use a FLASHLIGHT and a MIRROR - INSPECTION, FLEXIBLE to examine each steady bearing assembly for:

Stress
Cracks
Corrosion
Satisfactory surface protection
Condition of the bearing seals (missing, damages, bent, wear).

(c) If you find damage, replace the defective steady bearing assembly,
(Ref. AMM TASK 27-54-44-000-001) and (Ref. AMM TASK 27-54-44-400-001) and/or (Ref. AMM TASK 27-54-44-000-002) (Ref. AMM TASK 27-54-44-400-002).
(4) Examine each bevel and line gearbox assembly:

NOTE: The gearbox assembly is filled with a grease/semi-fluid but it is not a sealed unit. It is usual for this grease/semi-fluid to have some oil separation. The external surfaces of the gearbox can be moist with this oil. The oil in the unit that mixes with the grease/semi-fluid will change back during operation. The oil separation will decrease during in-service operation until the lubricant is in a stable condition. This will not cause damage to the unit.

(a) Make sure that each bevel and line gearbox assembly is correctly installed.
(b) Use a FLASHLIGHT and a MIRROR - INSPECTION, FLEXIBLE to examine the external surfaces of each bevel and line gearbox assembly for:

Cracks
Corrosion
Signs of leakage
Satisfactory surface protection.

(c) If you find damage, replace the defective bevel or line gear box assembly,
For the bevel gear box: (Ref. AMM TASK 27-54-48-000-001) and (Ref. AMM TASK 27-54-48-400-001).
For the line gear box: (Ref. AMM TASK 27-54-47-000-001) and (Ref. AMM TASK 27-54-47-400-001).
(5) Examine each actuator assembly:
(a) Make sure that each actuator is correctly installed.
(b) Make sure that the items that follow are correctly installed:

The offset gearbox
The torque limiter
The plug-in rotary actuator.

Cracks
Corrosion
Signs of leakage
Satisfactory surface protection.

(d) If you find damage, replace the defective actuator assembly:
At track 1: (Ref. AMM TASK 27-54-49-000-001) and (Ref. AMM TASK 27-54-49-400-001).
At track 2: (Ref. AMM TASK 27-54-49-000-002) and (Ref. AMM TASK 27-54-49-400-002).
At track 3: (Ref. AMM TASK 27-54-49-000-003) and (Ref. AMM TASK 27-54-49-400-003).
At track 4: (Ref. AMM TASK 27-54-49-000-004) and (Ref. AMM TASK 27-54-49-400-004).
(e) Details of the inspection of signs of leakage:
1 For actuator assemblies P/Ns starting with 791C/D, 792C/D/E, 793C/D, 794C/D, 1070C/D, 1071C/D, 1072C/D/E, 1073C/D, 1074C/D, 1075A refer to the note that follows:

NOTE: The rotary actuator and the offset gearbox are a complete unit which is lubricated with semi-fluid.
The housing of this actuator assembly is not a sealed unit. It is usual for the semi-fluid to have some oil separation. The external surfaces of the actuator assembly can be moist with this oil.
The oil in the unit that mixes with the semi-fluid will change back during operation. The oil separation will decrease during in-service operation until the lubricant is in a stable condition. This will not cause damage to the unit.

2 If you find a leak, do a check of the quantity of the semi-fluid in the related actuator assemblies:
(Ref. AMM TASK 27-54-00-612-001).
(f) Make sure that the torque limiter indicator has not operated.
(6) Examine the carriages at the track 1, 2, 3 and 4 positions:
(a) Make sure that the carriages are correctly installed.
(b) Use a FLASHLIGHT and a MIRROR - INSPECTION, FLEXIBLE to examine the carriages for:

Cracks
Corrosion
Satisfactory surface protection.

(c) If you find damage, replace the defective carriage:
At track 1: (Ref. AMM TASK 27-54-46-000-002) and (Ref. AMM TASK 27-54-46-400-002).
At tracks 2, 3 and 4: (Ref. AMM TASK 27-54-46-000-001) and (Ref. AMM TASK 27-54-46-400-001).
(7) Examine the flap link arm:
(a) Make sure that the flap drive lever and the flap drive arm are correctly installed and in good condition.
(b) If you find damage, replace the defective flap-actuator lever assemblies:
At tracks 1 and 2: (Ref. AMM TASK 27-54-55-000-001) and (Ref. AMM TASK 27-54-55-400-001).
At track 3: (Ref. AMM TASK 27-54-55-000-002) and (Ref. AMM TASK 27-54-55-400-002).
At track 4: (Ref. AMM TASK 27-54-55-000-003) and (Ref. AMM TASK 27-54-55-400-003).

5. Close-up
Subtask 27-54-00-410-050-A

A. Close Access
(1) Make sure that the work area is clean and clear of tools and other items.
(2) Install the access panels:
(a) For the LH wing, install the following panels:

(b) For the RH wing, install the following panels:

(3) Remove the 460005835 SLEEVE - GROUND LOCK on each MLG door actuating cylinder.
(4) Close the MLG doors (Ref. AMM TASK 32-12-00-410-001).

Subtask 27-54-00-865-054-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/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/FLP/CTL AND/MONG/SYS2	8CV	Q21

Subtask 27-54-00-860-060-A

C. Aircraft Maintenance Configuration
(1) Remove the 98D27803000000 LOCKING TOOL-FLAP SLAT LEVER,INT. POSITION (Ref. AMM TASK 27-00-00-080-002) from the flap/slat control lever.
(2) Retract the flaps fully (Ref. AMM TASK 27-50-00-866-009).

Subtask 27-54-00-942-053-A

D. 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 23:53:04 UTC