Thrust Reverser Slow Operation on Engine 1

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1. Possible Causes
· HCU-THRUST REV (4101KS)
· filter of the thrust reverser hydraulic isolation valve
· LOCK IND/PROX SENSOR-THRUST REV LOWER R ACTUATOR ( 4006KS )
· LOCK IND/PROX SENSOR-THRUST REV LOWER L ACTUATOR ( 4007KS )
· LVDT-THRUST REV UPPER R ACTUATOR ( 4003KS )
· LVDT-THRUST REV UPPER L ACTUATOR ( 4004KS )
2 Job Set-up Information
A. Referenced Information
REFERENCE DESIGNATION
Ref. AMM 71-13-00-010-010 Opening of the Fan Cowls 437AL(447AL),438AR(448AR)
Ref. AMM 71-13-00-410-010 Closing of the Fan Cowls 437AL(447AL),438AR(448AR)
Ref. AMM 78-31-00-710-041 Operational Test of the Thrust Reverser System with the CFDS
Ref. AMM 78-31-51-000-010 Removal of the Thrust Reverser Hydraulic Control Unit
Ref. AMM 78-31-51-400-010 Installation of the Thrust Reverser Hydraulic Control Unit
Ref. AMM 78-32-00-010-010 Opening of the Thrust Reverser Halves
Ref. AMM 78-32-00-410-010 Closing of the Thrust Reverser Halves
Ref. AMM 78-32-00-860-010 Manual Extension of the Thrust Reverser Translating Sleeves
Ref. AMM 78-32-00-860-011 Manual Retraction of the Thrust Reverser Translating Sleeves
Ref. AMM 78-32-43-000-010 Removal of the C-Duct Locking Actuator
Ref. AMM 78-32-43-400-010 Installation of the C-Duct Locking Actuator
Ref. AMM 78-32-48-000-010 Removal of the C-Duct Non-Locking Actuator
Ref. AMM 78-32-48-400-010 Installation of the C-Duct Non-Locking Actuator
Ref. AMM 78-37-51-600-010 Replacement of the Thrust Reverser Hydraulic Isolation Valve Filter
3. Fault Confirmation
Subtask 78-30-00-710-094-A
A. Test
(1) Do the operational test of the thrust reverser system with the CFDS (through FADEC 1A and 1B
menus) Ref. AMM 78-31-00-710-041 .
4. Fault Isolation
Subtask 78-30-00-810-078-A
A. Do a check of the thrust reverser system to make sure that the translating sleeves move freely Ref.
AMM 78-32-00-860-010 and Ref. AMM 78-32-00-860-011 .
(1) If the fault continues:
· Open the fan cowls 437AL and 438AR Ref. AMM 71-13-00-010-010 .
· Open the thrust reverser halves 451AL and 452AR Ref. AMM 78-32-00-010-010 .
· Examine the tubes between the HCU and the locking and non-locking actuators, for signs of
hydraulic fluid leaks. Repair as necessary.
(2) If the fault continues:
· Replace the HCU-THRUST REV (4101KS) Ref. AMM 78-31-51-000-010 and Ref.
AMM 78-31-51-400-010 .
(3) If the fault continues:
· Replace the filter of the thrust reverser hydraulic isolation valve Ref. AMM 78-37-51-600-010 .
(4) If the fault continues:
· Replace the LOCK IND/PROX SENSOR-THRUST REV LOWER R ACTUATOR ( 4006KS )
and the LOCK IND/PROX SENSOR-THRUST REV LOWER L ACTUATOR ( 4007KS ) Ref.
AMM 78-32-43-000-010 and Ref. AMM 78-32-43-400-010 .
(5) If the fault continues:
· Replace the LVDT-THRUST REV UPPER R ACTUATOR ( 4003KS ) and the LVDTTHRUST
REV UPPER L ACTUATOR ( 4004KS ) Ref. AMM 78-32-48-000-010 and Ref.
AMM 78-32-48-400-010 .
Subtask 78-30-00-710-095-A
B. Do the test given in Para. 3.
5. Close-up
Subtask 78-30-00-860-064-A
A. Put the aircraft back to its initial configuration.
(1) Make sure that the thrust reverser halves 451AL and 452AR are closed Ref.
AMM 78-32-00-410-010 .
(2) Make sure that the fan cowls 437AL and 438AR are closed Ref. AMM 71-13-00-410-010 . [Rev.6 from Feb 2017] 2026.04.04 04:38:07 UTC