W DOC AIRBUS | AMM A320F

Manual Reset of the Electrical Tertiary Lock System Hook [CFML]

TASK 78-37-00-440-802-A
Manual Reset of the Electrical Tertiary Lock System Hook

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.
CAUTION: MAKE SURE THAT THE TRANSCOWL IS NOT IN THE DEPLOYED POSITION WHEN YOU DO THE MANUAL RESET PROCEDURE. IF THE TRANSCOWL IS IN THE DEPLOYED POSITION, DAMAGE TO THE THRUST REVERSER CAN OCCUR.
1. Reason for the Job
A. This procedure gives the instructions to do a manual reset of the tertiary lock system hook. This procedure makes sure:
  • That the tertiary lock system is set in the ACTIVE condition, and
  • That the hook is set in the related active position.
B. Do not do this procedure when the translating cowl (transcowl) is in the deployed (aft) position. It is possible that the tertiary lock system could not lock the transcowl correctly (if you do the manual reset procedure with the transcowl in the deployed position).
C. When the tertiary lock system is in the ACTIVE condition, the tertiary lock system will lock the transcowl while the transcowl is in the stowed position. The tertiary lock system only permits the translating cowl to deploy if the aircraft is on the ground and the deploy condition is commanded.
D. If you do the tertiary lock system activation procedure, and do not do the tertiary lock system hook reset procedure (or do not manually stow and deploy the transcowl), a possible problem could occur. The tertiary lock system would read UNLOCKED to the aircraft, but the hook would prevent the transcowl from deploying manually. To prevent this possible problem you must manually push the tertiary lock system hook to the fully locked position.
2. Job Set-up Information
 A. Fixtures, Tools, Test and Support Equipment
REFERENCE
QTY
DESIGNATION
No specific
1
SCREWDRIVER
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 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 78-32-50-410-801-A
Manually Stow the Translating Cowl
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
TASK 78-37-00-440-803-A
Activation of the Electrical Tertiary Lock System
F Electrical Tertiary Lock System
3. Job Set-up
Subtask 78-37-00-941-055-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 WARNING NOTICE(S) is in position to tell persons not to energize FADEC 1(2).
Subtask 78-37-00-010-055-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 78-37-00-040-058-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).
Subtask 78-37-00-010-056-A
D. Get Access
   (1) Make sure that the thrust reverser 6 o'clock aft access door is open (Ref. AMM TASK 78-36-00-010-806).
   (2) Make sure that the transcowl is fully stowed (Ref. AMM TASK 78-32-50-410-801).
   (3) Make sure that the tertiary lock system lever (2) is in the ACTIVE position (Ref. AMM TASK 78-37-00-440-803).
4. Procedure
Subtask 78-37-00-440-054-A
A. Manually reset the tertiary lock system hook.
   (1) Find the hook reset hole in the body of the tertiary lock system (1).
   (2) Put a SCREWDRIVER with diameter less than 0.237 in. (6.02 mm) (or equivalent tool) into the hook reset hole until the tip of the SCREWDRIVER touches the hook.
   (3) Continue to push the SCREWDRIVER in the same direction to move the hook to the fully closed position.
   (4) Remove the SCREWDRIVER from the hook reset hole.
5. Close-up
Subtask 78-37-00-440-055-A
A. Do the reactivation of the thrust reverser system after nacelle maintenance (Ref. AMM TASK 78-30-00-440-807).
Subtask 78-37-00-410-052-A
B. Close Access
   (1) Make sure that the work area is clean and clear of tools and other items.
   (2) Close the thrust reverser 6 o'clock aft access door (Ref. AMM TASK 78-36-00-410-806).
   (3) 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
   (4) Remove the WARNING NOTICE(S).
[Rev.10 from 2021] 2026.04.01 03:37:23 UTC
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