Flap System Jam

TASK 27-51-00-810-810-A
Flap System Jam

1. Possible Causes

FLAP-PCU [6201CM]
WING TIP BRAKE [33CV]
WING TIP BRAKE [34CV]
PCU hydraulic motor

2. Job Set-up Information
A. Referenced Information

REFERENCE	DESIGNATION
AMM 12-22-27-640-004	Lubricate all Carriage Rollers on all Flap Tracks
AMM 27-50-00-866-010	Reset of the Torque Limiters of the Flap System on the Ground
AMM 27-51-51-000-001	Removal of the Flap Wing-Tip Brake
AMM 27-51-51-400-001	Installation of the Flap Wing-Tip Brake
AMM 27-54-00-200-001	Detailed Visual Inspection of the Transmission Assembly
AMM 27-54-00-710-001	Operational Test of the Flap System
AMM 27-54-49-000-001	Removal of the Flap Track 1 Actuator
AMM 27-54-49-400-001	Installation of the Flap Track 1 Actuator
AMM 27-54-51-000-001	Removal of the Power Control Unit of the Flap System
AMM 27-54-51-400-001	Installation of the Power Control Unit of the Flap System
AMM 27-54-54-000-001	Removal of the Hydraulic Motor of the Flap Power Control-Unit with the Pressure-Off Brake and the Valve Block Assembly
AMM 27-54-54-400-001	Installation of the Hydraulic Motor of the Flap Power Control-Unit with the Pressure-Off Brake and the Valve Block Assembly
AMM 27-54-61-000-001	Removal of the Inboard Flap
AMM 29-10-00-863-001	Pressurize the Green Hydraulic System with a Hydraulic Ground Power-Cart
AMM 29-10-00-864-002	Depressurize the Yellow Hydraulic System

3. Fault Confirmation
Subtask 27-51-00-710-066-A

A. Test
(1) Do the operational test of the flap system AMM 27-54-00-710-001:

if the flaps do not move, do the fault isolation procedure in Para 4.A.(1).
if the flaps move unsteady or slowly than normal, do the fault isolation procedure in Para 4.B..

(2) If you did not find a fault during the operational test procedure, go to 4.A.(5).

4. Fault Isolation
Subtask 27-51-00-810-057-A

A. Procedure
(1) Do a check of the Position Pick-off Units (PPUs) on the Centralized Fault Display System (CFDS) and make a record of the APPU and FPPU synchro angles, AMM 27-54-49-000-001 and AMM 27-54-49-400-001.

NOTE: This data will let you compare APPU and FPPU angles, before removal and after installation of a part of the flap transmission system. The difference in angles must be in the specified limits.

(2) Move the Flap control lever to a different applicable position and see if there is movement of the PCU (6201CM) output shafts:

if there is movement of the PCU output shafts, go to step 4.A.(5.).
if there is no movement of the PCU output shafts, do the next step.

(3) Disconnect the PCU Shaft:

if the left and right transmission shaft move freely, go to the next steps
if one of the left or right transmission shafts does not move freely, go to Para. 4.C..

(4) Replace the FLAP-PCU [6201CM] , AMM 27-54-51-000-001 and AMM 27-54-51-400-001.
(5) Do the reset of the torque limiters AMM 27-50-00-866-010 and record a possibly tripped torque limiter.
(a) If a tripped torque limiter was found:
Examine the related drive station, AMM 27-54-00-200-001. If necessary lubricate the items which were before cleaned for inspection, AMM 12-22-27-640-004.

NOTE: At this drive station (where the tripped torque limiter was found):
The failure will be downstream of the output shaft of the rotary actuator.
So it will be necessary to inspect all the mechanical items (Track beam, carriage and flap actuator lever etc.).

1 Do a detailed visual inspection of all the mechanical items (see NOTE above).
2 If you find a fault, correct or repair as necessary. Refer to the AMM 27-5X-XX for the applicable repair, or removal and installation procedures.
3 If you find no fault, replace the rotary actuators which have a tripped torque limiter.
(b) If no tripped torque limiter was found, do the next step.
(6) Do the inspection of the related WTB:
(a) Disconnect the transmission shafts on each side of the WTB 33CV (34CV) AMM 27-51-51-000-001.
(b) Make sure that you can easily turn the WTB by hand:

if you cannot easily turn the WTB by hand, or there is an incorrect noise, do the next step.

(c) Replace the WTB WING TIP BRAKE [33CV] or WING TIP BRAKE [34CV] ,
AMM 27-51-51-000-001 and AMM 27-51-51-400-001.
(d) If no fault is found (after the inspection) or if the fault continues, connect the transmission shafts again AMM 27-51-51-400-001
and go to Para. 4.B..

Subtask 27-51-00-810-091-A

B. Do the steps that follow:
(1) Do the operational test of the flap system (Ref. Para 3.A.(1)):

during the test make sure that the power transfer unit is set to OFF. This is to make sure that only the flap system 2 PCU hydraulic motor operates.
record the time necessary to extend the flaps and to retract the flaps.

(2) Do the operational test of the flap system (Ref. Para 3.A.(1)):

pressurize the Green hydraulic system for this test, AMM 29-10-00-863-001
during the test make sure that the power transfer unit is set to OFF. This is to make sure that only the flap system 1 hydraulic motor operates
during the test make sure that the Yellow hydraulic system is depressurized AMM 29-10-00-864-002
this is to make sure that only the flap system 1 hydraulic motor operates
record the time necessary to extend the flaps and to retract the flaps.

(3) Replace the PCU hydraulic motor on the slower system, AMM 27-54-54-000-001 and AMM 27-54-54-400-001.
(4) Do the test in Para. 3.A.:

If the fault continues, go to Para. 4.C..

Subtask 27-51-00-810-113-A

C. Inspection of the Transmission Assembly
(1) Do the detailed visual inspection of the transmission assembly, AMM 27-54-00-200-001.
(a) If it is not possible to move the flaps for the visual inspection, move the flaps manually, AMM 27-54-61-000-001.
(2) Remove each transmission shaft, one at a time to do a check for friction in each component of the flap system, (Ref. AMM chap. 27, removal and installation procedures).
(a) If you find a fault, correct or repair as necessary. Refer to the AMM 27-5X-XX for the applicable repair, or removal and installation procedures.
(b) Make sure that you install all components which were removed.

5. Close-up
Subtask 27-51-00-942-059-A

A. Remove the ground support and maintenance equipment, the special and standard tools and all other items.

Subtask 27-51-00-860-059-A

B. Put the aircraft back to its initial configuration.

[Rev.8 from Aug 2018] 2026.04.04 04:39:14 UTC