Installation of the Aprons and the Profiles

TASK 54-57-22-400-805-A
Installation of the Aprons and the Profiles

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.

ZONE: 410
ZONE: 420
FIN: 4020KM1 ** ON A/C NOT FOR ALL
FIN: 4020KM2 ** ON A/C NOT FOR ALL

1. Reason for the Job
Self explanatory
2. Job Set-up Information
A. Fixtures, Tools, Test and Support Equipment

REFERENCE	QTY	DESIGNATION
No specific	AR	ACCESS PLATFORM 3M (10 FT)- ADJUSTABLE

B. Work Zones and Access Panels

ZONE/ACCESS	ZONE DESCRIPTION
410	ENG 1 PYLON BOX AND FORWARD FAIRING
420	ENG 2 PYLON BOX AND FORWARD FAIRING
415AL, 415BR, 425AL, 425BR
FOR [4020KM1] (POWER PLANT-DEMOUNTABLE, ENG 1)
437AL, 438AR, 451AL, 452AR
FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENG 2)
447AL, 448AR, 461AL, 462AR

C. Referenced Information

REFERENCE	DESIGNATION
TASK 54-51-21-000-802-A	Removal of the Pylon Lateral Access-Doors
TASK 54-51-21-400-802-A	Installation of the Pylon Lateral Access-Doors
TASK 71-00-00-860-833-A	Procedure to Prevent Engine Motoring
TASK 71-13-00-410-802-A	Closing of the Fan Cowl Doors
TASK 78-30-00-040-805-A	Deactivation of the Thrust Reverser System for Ground Maintenance
TASK 78-30-00-440-805-A	Reactivation of the Thrust Reverser System after Ground Maintenance
TASK 78-36-00-410-802-A	Closing of the Thrust Reverser Cowl-Doors
Aprons and Profiles
Clearance Check

3. Job Set-up
Subtask 54-57-22-941-070-A ** ON A/C NOT FOR ALL

A. Safety Precautions
(1) Make sure that you did the procedure to prevent engine motoring
(Ref. AMM TASK 71-00-00-860-833).

Subtask 54-57-22-040-059-A ** ON A/C NOT FOR ALL

B. Deactivation of the Thrust Reverser

WARNING: MAKE SURE THAT THE THRUST REVERSER IS LOCKED. IF NOT, THE THRUST REVERSER CAN OPERATE ACCIDENTALLY AND CAUSE INJURY TO PERSONNEL AND/OR DAMAGE TO THE REVERSER.

(1) Make sure that the thrust reverser is unserviceable for maintenance (Ref. AMM TASK 78-30-00-040-805).

Subtask 54-57-22-010-079-A ** ON A/C NOT FOR ALL

C. Get Access
(1) Make sure that the ACCESS PLATFORM 3M (10 FT)- ADJUSTABLE is in position:
(a) For the left pylon, in zone 410
(b) For the right pylon, in zone 420.
(2) Make sure that the pylon lateral access-doors are removed (Ref. AMM TASK 54-51-21-000-802):
(a) For the left pylon: 415AL 415BR
(b) For the right pylon: 425AL 425BR.

Subtask 54-57-22-110-056-A ** ON A/C NOT FOR ALL

D. Preparation for Installation
(1) Make sure that the parts retained from the removed component are clean and in the correct condition.
(2) Do an inspection of the component interfaces and the adjacent area.

4. Procedure
Subtask 54-57-22-420-061-A ** ON A/C NOT FOR ALL

A. Installation of the Aprons and the Profiles

Aprons and Profiles ** ON A/C NOT FOR ALL

CAUTION: MAKE SURE THAT YOU INSTALL EACH OF THE SCREWS IN ITS CORRECT POSITION. THE SCREWS HAVE DIFFERENT LENGTHS. IF YOU DO NOT INSTALL EACH OF THE SCREWS IN ITS CORRECT POSITION, YOU CAN CAUSE DAMAGE.

(1) Installation of the profiles (11):
(a) Put and hold the profiles (11) in position.
(b) Install the bolts (9) and the nuts (5).
(c) Install the bolts (10) and the nuts (6).
(2) Installation of the LH apron (2):
(a) Put and hold the LH apron (2) in position.
(b) Install the screws (3), (4) and (12).
(c) Install the screw (1), the washer (7) and the nut (8).
(3) Installation of the RH apron (13):
(a) Put and hold the RH apron (13) in position.
(b) Install the screws (15), (16) and (19).
(c) Install the screw (14), the washer (17) and the nut (18).

Subtask 54-57-22-820-050-A ** ON A/C NOT FOR ALL

B. Check of the Clearance

Clearance Check ** ON A/C NOT FOR ALL

(1) Make sure that the out-of-flush dimension J1 between the external lateral panel (2) and the apron (1) across the line of flight is 0 +0.6 mm or -0.6 mm (0.0000 +0.0236 in. or -0.0236 in.).
(2) Make sure that the out-of-flush dimension J2 between the aft lateral panel (3) and the apron (1) across the line of flight is 0.2 +0.4 mm or -0.8 mm (0.0079 +0.0157 in. or -0.0315 in.).
(3) Make sure that the out-of-flush dimension J3 between the apron (1) and the profile (4) in the line of flight is 0 +0.3 mm or -0.9 mm (0.0000 +0.0118 in. or -0.0354 in.).
(4) Make sure that the out-of-flush dimension J4 between the upper fairing (5) and the profile (4) in the line of flight is 0 +0.3 mm or -0.9 mm (0.0000 +0.0118 in. or -0.0354 in.).

5. Close-up
Subtask 54-57-22-410-075-A ** ON A/C NOT FOR ALL

A. Close Access
(1) Install the pylon lateral access-doors (Ref. AMM TASK 54-51-21-400-802):
(a) For the left pylon: 415AL 415BR
(b) For the right pylon: 425AL 425BR.
(2) Close the thrust reverser cowl-doors (Ref. AMM TASK 78-36-00-410-802):
(a) FOR [4020KM1] (POWER PLANT-DEMOUNTABLE, ENG 1)
451AL 452AR
(b) FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENG 2)
461AL 462AR.
(3) Close the fan cowl doors (Ref. AMM TASK 71-13-00-410-802):
(a) FOR [4020KM1] (POWER PLANT-DEMOUNTABLE, ENG 1)
437AL 438AR
(b) FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENG 2)
447AL 448AR.

Subtask 54-57-22-440-057-A ** ON A/C NOT FOR ALL

B. Reactivation of the Thrust Reverser
(1) Make the thrust reverser serviceable after maintenance (Ref. AMM TASK 78-30-00-440-805).

Subtask 54-57-22-942-055-A ** ON A/C NOT FOR ALL

C. Aircraft Maintenance Configuration
(1) Make sure that the work area is clean and clear of tools and other items.
(2) Remove the access platform(s).
(3) Remove the WARNING NOTICE(S).

[Rev.10 from 2021] 2026.04.01 02:04:09 UTC