Locking of the Thrust-Reverser Upper Actuators [CFML]

TASK 78-31-41-440-802-A
Locking of the Thrust-Reverser Upper Actuators

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
A. This procedure gives the instructions on how to lock the right upper actuator and the left upper actuator.
B. The two upper actuators are also known as the synchronized locking feedback actuators.
C. When the actuators are locked they are in the usual position for automatic operation. The unlocking procedure is only done during maintenance. Do this procedure to lock the actuators after maintenance is complete before the aircraft is released for flight. Never permit flight with an actuator in the unlocked condition.
2. Job Set-up Information
A. Fixtures, Tools, Test and Support Equipment

REFERENCE	QTY	DESIGNATION
No specific	2	ACCESS PLATFORM 1M (3 FT)-ADJUSTABLE
No specific	AR	WARNING NOTICE(S)
98N7830H025-000	1	WAVE - UNLOCKING TR UP. ACTUATORS
98N7830H027-000	1	PIN - UNLOCKING TR UP. ACTUATORS

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
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 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)
Locking/Unlocking the Thrust-Reverser Upper Actuators

3. Job Set-up
Subtask 78-31-41-941-079-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) Make sure that the WARNING NOTICE(S) are 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) Make sure that the WARNING NOTICE(S) is in position to tell persons not to energize FADEC 1(2).

Subtask 78-31-41-010-098-A

B. Get Access
(1) Make sure that the fan cowl doors are open (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.

Subtask 78-31-41-040-082-A

C. Deactivation of the Thrust Reverser System for 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) Make sure that you did the deactivation of the thrust reverser system for nacelle maintenance (Ref. AMM TASK 78-30-00-040-807).
(2) Make sure that the ACCESS PLATFORM 1M (3 FT)-ADJUSTABLE is in position below the fan cowl doors.

4. Procedure
Subtask 78-31-41-440-073-A

A. Locking of the Thrust-Reverser Upper Actuators
(1) For PRE SPOL BD-TR-17014 without 98N7830H025-000 WAVE - UNLOCKING TR UP. ACTUATORS and POST SPOL BD-TR-17014 without 98N7830H027-000 PIN - UNLOCKING TR UP. ACTUATORS:
(a) Slowly turn the yellow hex (3) in the anti-clockwise direction to let the target (2) go back to the locked condition.

NOTE: When the actuator is in the locked condition, the target (2) will be between the two proximity sensors (1) and (5).

(b) Make sure that the upper actuator (4) is in the locked condition.
(c) Do the same procedure on the other upper actuator.
(2) For PRE SPOL BD-TR-17014 with 98N7830H025-000 WAVE - UNLOCKING TR UP. ACTUATORS:
(a) Remove the 98N7830H025-000 WAVE - UNLOCKING TR UP. ACTUATORS from the upper actuator (4).
(b) Slowly turn the yellow hex (3) in the anti-clockwise direction to let the target (2) go back to the locked condition.
(c) Make sure that the upper actuator (4) is in the locked condition.

NOTE: When the actuator (4) is in the locked condition, the target (2) will be between the two proximity sensors (1) and (5).

(d) Do the same procedure on the other upper actuator.
(3) For POST SPOL BD-TR-17014 with 98N7830H027-000 PIN - UNLOCKING TR UP. ACTUATORS:
(a) Remove the 98N7830H027-000 PIN - UNLOCKING TR UP. ACTUATORS from the upper actuator (4).
(b) Slowly turn the yellow hex (3) in the anti-clockwise direction to let the target (2) go back to the locked condition.
(c) Make sure that the upper actuator (4) is in the locked condition.

NOTE: When the actuator (4) is in the locked condition, the target (2) will be between the two proximity sensors (1) and (5).

(d) Do the same procedure on the other upper actuator.

5. Close-up
Subtask 78-31-41-440-074-A

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

Subtask 78-31-41-410-090-A

B. Close Access
(1) Make sure that the work area is clean and clear of tools and other items.
(2) 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.
(3) Remove the access platform(s).
(4) Remove the WARNING NOTICE(S).

[Rev.10 from 2021] 2026.04.01 13:13:27 UTC