Examination of the Environmental Control System (ECS) Interface Duct for Wear, Cracks and Damage

TASK 36-11-49-200-042-A
Examination of the Environmental Control System (ECS) Interface Duct for Wear, Cracks and Damage

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: WEAR APPLICABLE PERSONAL PROTECTIVE EQUIPMENT (PPE) WHEN YOU DO THIS TASK. BEFORE YOU USE PPE, READ, UNDERSTAND AND OBEY ALL INSTRUCTIONS FOR ITS USE. THESE INSTRUCTIONS INCLUDE INSTRUCTIONS FROM THE MANUFACTURER, YOUR EMPLOYER AND GOVERNMENT REGULATIONS. YOU CAN GET INJURED IF YOU DO NOT USE PPE. GET INSTRUCTIONS FROM YOUR EMPLOYER ON WHICH PPE IS NECESSARY.

WARNING: BE CAREFUL WHEN YOU USE CONSUMABLE MATERIALS. OBEY THE MATERIAL MANUFACTURER'S INSTRUCTIONS AND YOUR LOCAL REGULATIONS.

ZONE: 450
ZONE: 460

1. Reason for the Job
This task gives the procedure to examine the ECS interface duct for signs of wear, cracks and damage.
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	CALIPER
No specific	1	FLASHLIGHT
No specific	1	MICROMETER - EXTERNAL
No specific	1	MIRROR - INSPECTION
No specific	1	RULER 150 MM (6 IN) - METALLIC
No specific	AR	SAFETY CLIP - CIRCUIT BREAKER
No specific	AR	WARNING NOTICE(S)

B. Consumable Materials

REFERENCE	DESIGNATION
(Material No.PU1-0103)	Reprorubber Quicksetting Putty

C. Work Zones and Access Panels

ZONE/ACCESS	ZONE DESCRIPTION
450	ENG 1 THRUST REVERSER & EXHAUST SECTION
460	ENG 2 THRUST REVERSER & EXHAUST SECTION
191DB
FOR [4020KM1] (POWER PLANT-DEMOUNTABLE, ENG 1)
437AL, 438AR, 451AL, 452AR
FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENG 2)
447AL, 448AR, 461AL, 462AR

D. Referenced Information

REFERENCE	DESIGNATION
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 24-41-00-861-002-A-02	Energize the Aircraft Electrical Circuits from Engine 1(2)
TASK 24-41-00-862-002-A	De-energize the Aircraft Electrical Circuits Supplied from the External Power
TASK 24-41-00-862-002-A-01	De-energize the Aircraft Electrical Circuits Supplied from the APU
TASK 24-41-00-862-002-A-02	De-energize the Aircraft Electrical Circuits Supplied from the Engine 1(2)
TASK 36-11-49-000-824-A	Removal of the Environmental Control System (ECS) Interface Duct
TASK 36-11-49-400-824-A	Installation of the Environmental Control System (ECS) Interface Duct
TASK 71-00-00-790-802-A	Test No. 1 - Pneumatic Leak Test
TASK 71-00-00-860-833-A	Procedure to Prevent Engine Motoring
TASK 78-30-00-040-805-A	Deactivation of the Thrust Reverser System for Ground Maintenance
TASK 78-30-00-440-805-A	Reactivation of the Thrust Reverser System after Ground Maintenance
ECS Interface Duct - Location and Detail
FOR [4020KM1] (POWER PLANT-DEMOUNTABLE, ENG 1)
TASK 71-13-00-010-802-A	Opening of the Fan Cowl Doors
TASK 71-13-00-410-802-A	Closing of the Fan Cowl Doors
TASK 78-36-00-010-802-A	Opening of the Thrust Reverser Cowl-Doors
TASK 78-36-00-410-802-A	Closing of the Thrust Reverser Cowl-Doors
FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENG 2)
TASK 71-13-00-010-802-A	Opening of the Fan Cowl Doors
TASK 71-13-00-410-802-A	Closing of the Fan Cowl Doors
TASK 78-36-00-010-802-A	Opening of the Thrust Reverser Cowl-Doors
TASK 78-36-00-410-802-A	Closing of the Thrust Reverser Cowl-Doors

3. Job Set-up
Subtask 36-11-49-861-147-A ** ON A/C NOT FOR ALL

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

Subtask 36-11-49-860-146-A ** ON A/C NOT FOR ALL

B. Aircraft Maintenance Configuration
(1) Make sure that engine 1(2) shutdown occurs five minutes or more, before you do this procedure.
(2) In the cockpit, on AIR COND panel 30VU:
(a) Make sure that the ENG 1(2) BLEED pushbutton-switch is released (OFF legend is on).
(b) Make sure that the APU BLEED pushbutton-switch is released (ON legend is off).
(c) Put a WARNING NOTICE(S) in position to tell persons not to pressurize the pneumatic system.
(3) Do the procedure to prevent the engine motoring (Ref. AMM TASK 71-00-00-860-833).
(4) On access door 191DB, on the HP ground connector:
(a) Put the WARNING NOTICE(S) in position to tell persons not to pressurize the pneumatic system.

Subtask 36-11-49-865-264-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	AIR BLEED/ENG 1/CTL	2HA1	D11
122VU	AIR BLEED/ENG 1/MONG	3HA1	Z23
122VU	AIR BLEED/X FEED VALVE/NORM	1HV	Z20
FOR FIN: 4020KM2 (POWER PLANTDEMOUNTABLE, ENG 2)
49VU	AIR BLEED/X FEED/VALVE/BAT	2HV	D13
49VU	AIR BLEED/ENG 2/MONG	3HA2	D12
122VU	AIR BLEED/ENG 2/CTL	2HA2	Z22

Subtask 36-11-49-010-333-A ** ON A/C NOT FOR ALL

D. Get Access
(1) Open the fan cowl doors:
(a) FOR [4020KM1] (POWER PLANT-DEMOUNTABLE, ENG 1)

437AL and 438AR (Ref. AMM TASK 71-13-00-010-802).

(b) FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENG 2)

447AL and 448AR (Ref. AMM TASK 71-13-00-010-802).

Subtask 36-11-49-040-202-A ** ON A/C NOT FOR ALL

E. Deactivation of the Thrust Reverser (T/R)

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) Do the deactivation of the T/R system for ground maintenance (Ref. AMM TASK 78-30-00-040-805).

Subtask 36-11-49-010-334-A ** ON A/C NOT FOR ALL

F. Get Access
(1) Open the T/R cowl doors:
(a) FOR [4020KM1] (POWER PLANT-DEMOUNTABLE, ENG 1)

452AR and 451AL (Ref. AMM TASK 78-36-00-010-802).

(b) FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENG 2)

462AR and 461AL (Ref. AMM TASK 78-36-00-010-802).

(2) Put an ACCESS PLATFORM 2M (6 FT) - ADJUSTABLE in position below the T/R cowl door.
(3) Use a FLASHLIGHT and a MIRROR - INSPECTION to do the inspection.

4. Procedure
Subtask 36-11-49-220-058-A ** ON A/C NOT FOR ALL

A. Examination of the ECS Interface Duct for Wear, Cracks and Damage

CAUTION: INSTALL PROTECTION COVERS ON ALL THE OPENINGS IMMEDIATELY TO PREVENT DAMAGE TO THE ENGINE.

CAUTION: WIPE CLEAN ALL PARTS AND TOOLS AS NECESSARY TO REMOVE UNWANTED DEBRIS AND PREVENT DAMAGE TO THE ENGINE AND ADJACENT COMPONENTS.

(1) Do not discard a part until you are sure that there are no repairs available. If you reject a part and there are no repairs available, contact Collins Aerospace for the instructions.
(2) Visually examine the circumference of the walls on the ECS interface duct for signs of wear, cracks and damage:
(a) If you find cracks, replace the ECS interface duct (Ref. AMM TASK 36-11-49-000-824) and (Ref. AMM TASK 36-11-49-400-824).
(b) If you find wear, do the steps that follow:
1 Measure and record the length and width of the wear with a RULER 150 MM (6 IN) - METALLIC, MICROMETER - EXTERNAL or a CALIPER.
2 Do not push or move the ECS interface duct while you measure the damage.
3 Measure the depth of the wear with Reprorubber Quicksetting Putty (Material No.PU1-0103) .

Damage Depth	Instruction
Less than 0.020 IN. (0.5080 MM).	Examine the ECS interface duct at 3000 Flight Cycle (FC) intervals.
Larger than 0.020 IN. (0.5080 MM) or less than or equal to 0.025 IN. (0.6350 MM).	Replace the duct nearest to 500 Flight Cycle (FC) or three months (one of the two that comes first) (Ref. AMM TASK 36-11-49-000-824) and (Ref. AMM TASK 36-11-49-400-824).
Larger than 0.025 IN. (0.6350 MM).	Replace the duct (Ref. AMM TASK 36-11-49-000-824) and (Ref. AMM TASK 36-11-49-400-824).

Table - ECS Interface Duct - Allowable Damage Limits

(c) If you find damage, do the steps that follow:
1 Record the damage.
2 Contact Collins Aerospace with the recorded results.

5. Close-up
Subtask 36-11-49-865-265-A ** ON A/C NOT FOR ALL

A. Remove the safety clip(s) and the tag(s) and close this(these) circuit breaker(s):

PANEL	DESIGNATION	FIN	LOCATION
** ON A/C NOT FOR ALL
FOR FIN: 4020KM1 (POWER PLANTDEMOUNTABLE, ENG 1)
49VU	AIR BLEED/ENG 1/CTL	2HA1	D11
122VU	AIR BLEED/ENG 1/MONG	3HA1	Z23
122VU	AIR BLEED/X FEED VALVE/NORM	1HV	Z20
FOR FIN: 4020KM2 (POWER PLANTDEMOUNTABLE, ENG 2)
49VU	AIR BLEED/X FEED/VALVE/BAT	2HV	D13
49VU	AIR BLEED/ENG 2/MONG	3HA2	D12
122VU	AIR BLEED/ENG 2/CTL	2HA2	Z22

Subtask 36-11-49-790-069-A ** ON A/C NOT FOR ALL

B. Leak Test
(1) Do test no. 1 - pneumatic leak test (Ref. AMM TASK 71-00-00-790-802):
(a) Make sure that there are no leaks.

Subtask 36-11-49-410-245-A ** ON A/C NOT FOR ALL

C. Close Access
(1) Make sure that the work area is clean and clear of tools and other items.
(2) Remove the access platform(s).
(3) Close the T/R cowl doors:
(a) FOR [4020KM1] (POWER PLANT-DEMOUNTABLE, ENG 1)

452AR and 451AL (Ref. AMM TASK 78-36-00-410-802).

(b) FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENG 2)

462AR and 461AL (Ref. AMM TASK 78-36-00-410-802).

Subtask 36-11-49-440-142-A ** ON A/C NOT FOR ALL

D. Do the reactivation of the T/R after ground maintenance
(Ref. AMM TASK 78-30-00-440-805).

Subtask 36-11-49-410-246-A ** ON A/C NOT FOR ALL

E. Close Access
(1) Close the fan cowl doors:
(a) FOR [4020KM1] (POWER PLANT-DEMOUNTABLE, ENG 1)

437AL and 438AR (Ref. AMM TASK 71-13-00-410-802).

(b) FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENG 2)

447AL and 448AR (Ref. AMM TASK 71-13-00-410-802).

(2) Remove the WARNING NOTICE(S).

Subtask 36-11-49-862-132-A ** ON A/C NOT FOR ALL

F. De-energize the aircraft electrical circuits
(Ref. AMM TASK 24-41-00-862-002).

[Rev.10 from 2021] 2026.04.01 01:12:11 UTC