Removal of the Pylon Duct Assembly

TASK 36-11-49-000-825-A
Removal of the Pylon Duct Assembly

WARNING: MAKE SURE THAT THE PNEUMATIC SYSTEM IS DEPRESSURIZED BEFORE YOU START WORK. PRESSURIZED AIR CAN CAUSE INJURY TO PERSONNEL.

WARNING: BE CAREFUL WHEN YOU DO WORK ON THE ENGINE AFTER SHUTDOWN. THE ENGINE CAN STAY HOT FOR A LONG TIME. IF YOU DO NOT OBEY THIS INSTRUCTION, INJURY CAN OCCUR.

WARNING: ALWAYS USE APPLICABLE GLOVES TO TOUCH HOT PARTS. HOT PARTS CAN CAUSE INJURY TO PERSONS.

WARNING: PUT THE SAFETY DEVICES AND THE WARNING NOTICES IN POSITION BEFORE YOU START A TASK ON OR NEAR:

THE FLIGHT CONTROLS
THE FLIGHT CONTROL SURFACES
THE LANDING GEAR AND THE RELATED DOORS
COMPONENTS THAT MOVE.

MOVEMENT OF COMPONENTS CAN KILL OR CAUSE INJURY TO PERSONS AND/OR CAN CAUSE DAMAGE TO THE EQUIPMENT.

CAUTION: BE VERY CAREFUL WHEN YOU DO WORK ON OR NEAR THE AIR-CONDITIONING DUCTS. THE DUCTS ARE MADE OF THIN MATERIAL AND YOU CAN EASILY BREAK THEM.

ZONE: 410
ZONE: 420
ZONE: 450
ZONE: 460

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	1	ACCESS PLATFORM 4M (13 FT)-ADJUSTABLE
No specific	AR	PLUG - BLANKING
No specific	AR	SAFETY CLIP - CIRCUIT BREAKER
No specific	AR	WARNING NOTICE(S)
98D27803000000	1	LOCKING TOOL-FLAP SLAT LEVER,INT. POSITION
98L12003001000	1	HARNESS,SAFETY

B. Work Zones and Access Panels

ZONE/ACCESS	ZONE DESCRIPTION
410	ENG 1 PYLON BOX AND FORWARD FAIRING
420	ENG 2 PYLON BOX AND FORWARD FAIRING
450	ENG 1 THRUST REVERSER & EXHAUST SECTION
460	ENG 2 THRUST REVERSER & EXHAUST SECTION
191DB
FOR [1000EM1] (ENGINE-1)
437AL, 438AR, 451AL, 452AR
FOR [1000EM2] (ENGINE-2)
447AL, 448AR, 461AL, 462AR
FOR [4020KM1] (POWER PLANT-DEMOUNTABLE, ENG 1)
413BT, 413CT, 413DT
FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENG 2)
423BT, 423CT, 423DT

C. Referenced Information

REFERENCE	DESIGNATION
TASK 12-00-00-481-002-A	Installation of the Wingrip
TASK 24-41-00-861-002-A	Energize the Aircraft Electrical Circuits from the External Power
TASK 24-41-00-861-002-A-01	Energize the Aircraft Electrical Circuits from the APU
TASK 27-00-00-480-002-A	Installation of the Flap/Slat Control-Lever Locking Tool (98D27803000000)
TASK 36-11-49-000-826-A	Removal of the Sense Line between the Bleed-Air Precooler Exchanger (Upstream) and the Bleed Differential Pressure-Transducer
TASK 36-22-15-000-802-A	Removal of the Pylon Overheat Sensing-Elements
TASK 49-00-00-860-009-A	APU Shutdown by External Power (131-9(A))
TASK 49-00-00-860-009-A-01	APU Shutdown by Batteries (131-9(A))
TASK 54-52-11-000-805-A	Removal of the Access Skin Panels
TASK 71-00-00-860-833-A	Procedure to Prevent Engine Motoring
TASK 71-00-51-000-802-A	Removal of the Power Plant (Bootstrap Method)
TASK 71-00-51-000-802-A-01	Removal of the Power Plant (JacXson Method)
TASK 71-13-00-010-802-A	Opening of the Fan Cowl Doors
TASK 78-30-00-040-805-A	Deactivation of the Thrust Reverser System for Ground Maintenance
TASK 78-36-00-010-802-A	Opening of the Thrust Reverser Cowl-Doors
Transversal Fairing Support
Pylon Duct Assembly

3. Job Set-up
Subtask 36-11-49-861-111-A ** ON A/C NOT FOR ALL

A. Energize the aircraft electrical circuits
(Ref. AMM TASK 24-41-00-861-002) or (Ref. AMM TASK 24-41-00-861-002).

Subtask 36-11-49-941-130-A ** ON A/C NOT FOR ALL

B. Safety Precautions
(1) On AIR COND panel 30VU:
(a) Make sure that the ENG 1(2) BLEED pushbutton switch is released (OFF legend on).
(b) Make sure that the APU BLEED pushbutton switch is released (ON legend off).
(c) Put a WARNING NOTICE(S) in position to tell persons not to operate the pneumatic system.
(2) Do the procedure to prevent engine motoring
(Ref. AMM TASK 71-00-00-860-833).
(3) On access door 191DB, on the HP ground connector:
(a) Put a WARNING NOTICE(S) in position to tell persons not to pressurize the pneumatic system.
(4) Put on and attach a 98L12003001000 HARNESS,SAFETY before you start work in the work area (Ref. AMM TASK 12-00-00-481-002).
(5) On FLAPS panel 114VU:

Put the 98D27803000000 LOCKING TOOL-FLAP SLAT LEVER,INT. POSITION in position on the flap/slat control lever (Ref. AMM TASK 27-00-00-480-002).
Put a WARNING NOTICE(S) on the flap/slat control lever to tell persons not to operate the flap/slat controls.

(6) Put an ACCESS PLATFORM 4M (13 FT)-ADJUSTABLE in position above the pylon.

Subtask 36-11-49-865-189-A ** ON A/C NOT FOR ALL

C. Open, safety and tag this(these) circuit breaker(s):

PANEL	DESIGNATION	FIN	LOCATION
** ON A/C NOT FOR ALL
FOR FIN: 4020KM1 (POWER PLANTDEMOUNTABLE, ENG 1)
49VU	ENGINE/1/FADEC A/AND EIU 1	2KS1	A04
49VU	AIR BLEED/ENG 1/CTL	2HA1	D11
** ON A/C NOT FOR ALL
121VU	ENGINE/ENG1/FADEC B/AND EIU 1	4KS1	R41
** ON A/C NOT FOR ALL
121VU	ENGINE/ENG1/FADEC B/AND EIU 1	4KS1	R40
** ON A/C NOT FOR ALL
122VU	AIR BLEED/ENG 1/MONG	3HA1	Z23
FOR FIN: 4020KM2 (POWER PLANTDEMOUNTABLE, ENG 2)
49VU	ENGINE/2/FADEC A/AND EIU 2	2KS2	A05
49VU	AIR BLEED/ENG 2/MONG	3HA2	D12
** ON A/C NOT FOR ALL
121VU	ENGINE/ENG2/FADEC B/AND EIU2	4KS2	Q40
** ON A/C NOT FOR ALL
121VU	ENGINE/ENG2/FADEC B/AND EIU2	4KS2	R41
** ON A/C NOT FOR ALL
122VU	AIR BLEED/ENG 2/CTL	2HA2	Z22

Subtask 36-11-49-010-223-A ** ON A/C NOT FOR ALL

D. Get Access
(1) Open the fan cowl doors (Ref. AMM TASK 71-13-00-010-802).
(a) FOR [1000EM1] (ENGINE-1)
437AL and 438AR.
(b) FOR [1000EM2] (ENGINE-2)
447AL and 448AR.

Subtask 36-11-49-040-193-A ** ON A/C NOT FOR ALL

E. Deactivation of the Thrust-Reverser for Maintenance

WARNING: MAKE THE THRUST REVERSER UNSERVICEABLE (INSTALL AND SAFETY THE ICU LOCKOUT PIN) BEFORE YOU DO WORK ON OR AROUND THE THRUST REVERSER. IF YOU DO NOT INSTALL AND SAFETY THE ICU LOCKOUT PIN, YOU CAN CAUSE ACCIDENTAL OPERATION OF THE THRUST REVERSER AND INJURY TO PERSONS AND/OR DAMAGE TO THE EQUIPMENT.

(1) Make the thrust reverser unserviceable for maintenance (Ref. AMM TASK 78-30-00-040-805).

Subtask 36-11-49-010-315-A ** ON A/C NOT FOR ALL

F. Get Access
(1) Remove the access panels (Ref. AMM TASK 54-52-11-000-805):
(a) FOR [4020KM1] (POWER PLANT-DEMOUNTABLE, ENG 1)
413BT, 413CT and 413DT.
(b) FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENG 2)
423BT, 423CT and 423DT.

Subtask 36-11-49-010-312-A ** ON A/C NOT FOR ALL

G. Get Access
(1) Open the thrust-reverser cowl doors (Ref. AMM TASK 78-36-00-010-802).
(a) FOR [1000EM1] (ENGINE-1)
451AL and 452AR.
(b) FOR [1000EM2] (ENGINE-2)
461AL and 462AR.
(2) Put an ACCESS PLATFORM 2M (6 FT) - ADJUSTABLE in position below the pylon.

Subtask 36-11-49-010-224-A ** ON A/C NOT FOR ALL

H. Removal of the Components
(1) If you use the APU to energize the electrical circuits, stop the APU:

For GTCP 36-300 APU (Ref. AMM D/O 49-00-00-86)
For APS 3200 APU (Ref. AMM D/O 49-00-00-86)
For 131-9(A) APU (Ref. AMM TASK 49-00-00-860-009).

(2) In the cockpit, on the SD bleed page:
(a) Make sure that the pressure and the temperature of the bleed-air duct system are in ambient conditions.

WARNING: MAKE SURE THAT THE PNEUMATIC SYSTEM IS DEPRESSURIZED BEFORE YOU START WORK. PRESSURIZED AIR CAN CAUSE INJURY TO PERSONNEL.

WARNING: DO NOT TOUCH THE UNIT UNTIL IT IS SUFFICIENTLY COOL TO PREVENT BURNS WHEN YOU DO THE MAINTENANCE TASK(S).

(3) Remove the engine (Ref. AMM TASK 71-00-51-000-802).
(4) Remove the sense line between the bleed-air precooler exchanger (upstream) and the bleed differential pressure-transducer (Ref. AMM TASK 36-11-49-000-826).
(5) Remove the related pylon overheat sensing-elements (Ref. AMM TASK 36-22-15-000-802).
(6) Remove the support of the overheat sensing elements (1), the closing rib (6) and the transversal fairing support (2):

Transversal Fairing Support ** ON A/C NOT FOR ALL

(a) Remove the support of the overheat sensing-elements (1):
1 Cut the lacing tapes that attach the harnesses to the support of the overheat sensing elements (1).
2 Remove the bolts (5) and washers (4) from the closing rib (6) and from the support of the overheat sensing elements (1).
3 Remove the support of the overheat sensing elements (1).
(b) Remove the closing rib (6):
1 Remove the bolts (9), the washers (10) and the nuts (11) from the closing rib (6) and from the transversal fairing support (2).
2 Remove the eight bolts (8), washers (7) and nuts (12) from the pylon attach fittings (3).
3 Remove the closing rib (6) from the pylon attach fittings (3).
(c) Remove the transversal fairing support (2):
1 Remove the four bolts (13) and nuts (14) from the transversal fairing support (2) and from the pylon attach fittings (3).
2 Remove the transversal fairing support (2) from the pylon attach fittings (3).

4. Procedure
Subtask 36-11-49-020-143-A ** ON A/C NOT FOR ALL

A. Removal of the Pylon Duct Assembly
(1) Remove the elbow (8):
(a) Remove the coupling (2) from the elbow (8) and the duct (1).
(b) Remove the seal (3) and discard it.
(c) Remove the bolt (4), washer (5), bushings (6) and (9) and the nut (10) from the elbow (8) and the support (7).
(d) Remove the bolt (14), washer (13), bushing (12) and the nut (11) from the elbow (8) and the support (7).
(e) Remove the elbow (8) from the support (7).
(2) Loosen the bolts (16) from the flange (15). This will release the duct (1) and make the removal easier.
(3) Remove the lateral supports (24) and (25):
(a) Remove the screws (23) and the washers (22) from the lateral supports (24) and (25).
(b) Remove the screws (20) and the washers (21) from the lateral supports (24) and (25).
(c) Remove the lateral supports (24) and (25) from the supports (26) and the duct (1).
(4) Remove the half-plates (28) and (32) from the flange (33):
(a) Remove the nuts (27).
(b) Remove the half-plates (28).
(c) Remove the glass-fiber yarn braid (30).

NOTE: You can remove the glass-fiber yarn braid (30) after the removal of the duct (1).

(d) Remove the fixing axes (29).
(e) Remove the washers (31).
(f) Remove the half-plates (32).
(5) Remove the duct (1):
(a) Remove the coupling (17) from the duct (1) and the bleed-air precooler exchanger (19).
(b) Remove the seal (18) and discard it.
(c) Remove the duct (1) from the pylon.
(d) Put PLUG - BLANKING on the bleed-air precooler exchanger (19) and the duct (1).

[Rev.10 from 2021] 2026.04.01 01:11:28 UTC