Detailed Inspection of Aft Core Cowl Landing of Finger Seals [CFML]

TASK 78-32-46-220-802-A
Detailed Inspection of Aft Core Cowl Landing of Finger Seals

WARNING: BE CAREFUL WHEN YOU DO WORK ON THE ENGINE PARTS AFTER THE ENGINE SHUTDOWN. USE APPLICABLE THERMAL GLOVES. THE ENGINE PARTS CAN STAY HOT FOR ONE HOUR AFTER SHUTDOWN AND CAN BURN YOU.

ZONE: 400

1. Reason for the Job
Refer to the MPD TASK: 783200-L3
DETAILED INSPECTION OF AFT CORE COWL LANDING OF FINGER SEALS.
2. Job Set-up Information
A. Fixtures, Tools, Test and Support Equipment

REFERENCE	QTY	DESIGNATION
No specific	1	ACCESS PLATFORM 2M (6 FT)
No specific	1	LIGHT SOURCE - INSPECTION
No specific	AR	WARNING NOTICE(S)

B. Work Zones and Access Panels

ZONE/ACCESS	ZONE DESCRIPTION
400	POWER PLANT, NACELLES AND PYLONS
FOR [4020KM1] (POWER PLANT-DEMOUNTABLE, ENGINE 1)
437AL, 438AR, 451AL, 452AR
FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENGINE 2)
447AL, 448AR, 461AL, 462AR

C. Referenced Information

REFERENCE	DESIGNATION
TASK 71-13-00-010-803-A	Opening of the Fan Cowl Doors
TASK 71-13-00-410-803-A	Closing of the Fan Cowl Doors
TASK 78-30-00-040-807-A	Deactivation of the Thrust Reverser System for Nacelle Maintenance (ICU)
TASK 78-30-00-440-807-A	Reactivation of the Thrust Reverser System after Nacelle Maintenance (ICU)
TASK 78-32-46-000-802-A	Removal of the Aft Core Cowl Finger Seal Landing
TASK 78-32-46-400-802-A	Installation of the Aft Core Cowl Finger Seal Landing
TASK 78-36-00-010-806-A	Opening of the Thrust Reverser Cowl Doors
TASK 78-36-00-410-806-A	Closing of the Thrust Reverser Cowl Doors
Aft Core Cowl Finger Seal Landings

3. Job Set-up
Subtask 78-32-46-941-059-A

A. Safety Precautions
(1) On the center pedestal, on ENG panel 115VU:
(a) Make sure that the ENG/MODE selector switch is in the NORM position.
(b) Make sure that the ENG/MASTER 1(2) control switch was in the OFF position not less than five minutes before you do this procedure.
(c) Put WARNING NOTICE(S) in position to tell persons not to operate:

The ENG/MODE selector switch
The ENG/MASTER 1(2) control switch.

(2) On the ENG section of maintenance panel 50VU:
(a) Make sure that the ON legend of the FADEC GND PWR/1(2) pushbutton switch is off.
(b) Put a WARNING NOTICE(S) in position to tell persons not to energize FADEC 1(2).

Subtask 78-32-46-010-072-A

B. Get Access
(1) Open the fan cowl doors (Ref. AMM TASK 71-13-00-010-803):
(a) FOR [4020KM1] (POWER PLANT-DEMOUNTABLE, ENGINE 1)
437AL 438AR
(b) FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENGINE 2)
447AL 448AR
(2) Put an ACCESS PLATFORM 2M (6 FT) in position.

Subtask 78-32-46-040-060-A

C. Deactivation of the Thrust Reverser System for Nacelle Maintenance

WARNING: YOU MUST DEACTIVATE THE THRUST REVERSER BEFORE YOU DO WORK ON OR AROUND IT. IF YOU DO NOT, THE THRUST REVERSER CAN OPERATE ACCIDENTALLY AND CAUSE AN INJURY AND/OR DAMAGE.

(1) Do the deactivation of the thrust reverser system for nacelle maintenance (Ref. AMM TASK 78-30-00-040-807).

Subtask 78-32-46-010-073-A

D. Get Access
(1) Open the thrust reverser cowl-doors (Ref. AMM TASK 78-36-00-010-806):
(a) FOR [4020KM1] (POWER PLANT-DEMOUNTABLE, ENGINE 1)
451AL 452AR
(b) FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENGINE 2)
461AL 462AR

4. Procedure
Subtask 78-32-46-220-051-A

A. Detailed Inspection of the Aft Core Cowl Finger Seal Landing Surface with Anti-wear Coating Treatment

NOTE: You can use an LIGHT SOURCE - INSPECTION for inspection.

NOTE: This procedure is applicable to the left and the right thrust reverser aft core cowl finger seal landing surfaces.

(1) Do a detailed inspection of the aft core cowl finger seal landings (1), (2) and (3) for damage on the coating area.
(a) Make sure that the carbide tungsten coating is not missing over its entire thickness, even locally.

NOTE: It is normal to observe some marks due to contact between finger seal and landing. Worn coating generates depth. If excessive wear depth can be detected by human finger, replace the aft core cowl finger seal landings (1), (2) and (3) (Ref. AMM TASK 78-32-46-000-802) and (Ref. AMM TASK 78-32-46-400-802).

NOTE:

Aft Core Cowl Finger Seal Landings

5. Close-up
Subtask 78-32-46-410-066-A

A. Close Access
(1) Make sure that the work area is clean and clear of tools and other items.
(2) Close the thrust reverser cowl-doors (Ref. AMM TASK 78-36-00-410-806):
(a) FOR [4020KM1] (POWER PLANT-DEMOUNTABLE, ENGINE 1)
451AL 452AR
(b) FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENGINE 2)
461AL 462AR

Subtask 78-32-46-440-057-A

B. Do the reactivation of the thrust reverser system after nacelle maintenance (Ref. AMM TASK 78-30-00-440-807).

Subtask 78-32-46-410-067-A

C. Close Access
(1) Close the fan cowl doors (Ref. AMM TASK 71-13-00-410-803):
(a) FOR [4020KM1] (POWER PLANT-DEMOUNTABLE, ENGINE 1)
437AL 438AR
(b) FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENGINE 2)
447AL 448AR
(2) Remove the access platform(s).
(3) Remove the WARNING NOTICE(S).

[Rev.10 from 2021] 2026.04.01 03:36:17 UTC