Removal of the Actuator Fitting of the Thrust Reverser Cowl Opening System (COS) [CFML]

TASK 78-36-51-000-805-A
Removal of the Actuator Fitting of the Thrust Reverser Cowl Opening System (COS)

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.

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

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

B. Work Zones and Access Panels

ZONE/ACCESS	ZONE DESCRIPTION
FOR [4020KM1] (POWER PLANT-DEMOUNTABLE, ENGINE 1)
437AL, 438AR
FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENGINE 2)
447AL, 448AR

C. Referenced Information

REFERENCE	DESIGNATION
TASK 71-13-00-010-803-A	Opening of the Fan Cowl Doors
TASK 78-30-00-040-807-A	Deactivation of the Thrust Reverser System for Nacelle Maintenance (ICU)
TASK 78-31-44-000-802-A	Removal of the Sync Tubes, Sync Shafts, Flex Tubes and Flex Shaft
TASK 78-36-51-000-802-A	Removal of the Thrust Reverser Cowl Opening System
Thrust Reverser COS Actuator Fitting

3. Job Set-up
Subtask 78-36-51-941-064-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, and
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 78-36-51-010-080-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) - ADJUSTABLE in position.

Subtask 78-36-51-040-066-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).

4. Procedure
Subtask 78-36-51-020-058-A

A. Removal of the Actuator Fitting of the Thrust Reverser Cowl Opening System (COS)
(1) Remove the thrust reverser COS actuator (Ref. AMM TASK 78-36-51-000-802).
(2) Remove the COS actuator fittings (7) and (8).
(a) Remove the bolts (1) and (4) that attach the P-clamps (2) and (5) and the flexshafts (3) and (6) to the thrust reverser (Ref. AMM TASK 78-31-44-000-802).
(b) Remove the COS actuator fittings (7) and (8) from the thrust reverser.
1 Mark and record the position of the COS actuator fittings (7) and (8) on the forward frame of the thrust reverser.
2 Remove the screws (9) that attach the COS actuator fittings (7) and (8) to the thrust reverser.
3 Remove the COS actuator fittings (7) and (8) from the thrust reverser.

NOTE: Keep the removed COS actuator fittings as a template for the installation of new fittings.

[Rev.10 from 2021] 2026.04.01 03:37:17 UTC