Detailed Inspection of the Engine Air-Intake Protection Ducts

TASK 30-21-49-220-801-A
Detailed Inspection of the Engine Air-Intake Protection Ducts

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: 438
ZONE: 448

1. Reason for the Job
Refer to the MPD TASK: 302149-03
DETAILED INSPECTION OF ENGINE AIR INTAKE PROTECTION DUCTS.

NOTE: The NAI duct is an interchangeable part. For the same duct, there are different part numbers with different conditions (form and color). The different part numbers stay fully interchangeable.

2. Job Set-up Information
A. Fixtures, Tools, Test and Support Equipment

REFERENCE	QTY	DESIGNATION
No specific	1	ACCESS PLATFORM 1M(3 FT)
No specific	1	LIGHT SOURCE - INSPECTION
No specific	1	MAGNIFYING GLASS POWER 10X
No specific	1	MIRROR - INSPECTION
No specific	AR	SAFETY CLIP - CIRCUIT BREAKER

B. Consumable Materials

REFERENCE	DESIGNATION
(Material No.PU1-0001)	lint-free cotton cloth

C. Work Zones and Access Panels

ZONE/ACCESS	ZONE DESCRIPTION
438	FAN COWL
448	FAN COWL
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 24-42-00-861-001-A	Energize the Ground Service Network from the External Power
TASK 24-42-00-862-001-A	De-energize the Ground Service Network Supplied from the External Power
TASK 30-21-49-000-807-A	Removal of the Nacelle Anti-Ice (NAI) Duct
TASK 30-21-49-400-807-A	Installation of Nacelle Anti-Ice (NAI) Duct
TASK 71-00-00-860-833-A	Procedure to Prevent Engine Motoring
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 78-30-00-040-805-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
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
Nacelle Anti-Ice (NAI) Ducts

3. Job Set-up
Subtask 30-21-49-861-088-A ** ON A/C NOT FOR ALL

A. Energize the ground service network
(Ref. AMM TASK 24-42-00-861-001).

Subtask 30-21-49-941-114-A ** ON A/C NOT FOR ALL

B. Safety Precautions
(1) Do the procedure to prevent engine motoring
(Ref. AMM TASK 71-00-00-860-833).

Subtask 30-21-49-865-117-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)
122VU	ANTI ICE/ENG/1	1DN1	X10
FOR FIN: 4020KM2 (POWER PLANTDEMOUNTABLE, ENG 2)
122VU	ANTI ICE/ENG/2	1DN2	W10

Subtask 30-21-49-010-160-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 [4020KM1] (POWER PLANT-DEMOUNTABLE, ENG 1)
437AL 438AR
(b) FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENG 2)
447AL 448AR

Subtask 30-21-49-040-095-A ** ON A/C NOT FOR ALL

E. Deactivation of the Thrust Reverser System for Ground 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) Do the deactivation of the thrust reverser system for ground maintenance (Ref. AMM TASK 78-30-00-040-805).

Subtask 30-21-49-010-161-A ** ON A/C NOT FOR ALL

F. Get Access
(1) Open the thrust reverser cowl-doors (Ref. AMM TASK 78-36-00-010-802):
(a) FOR [4020KM1] (POWER PLANT-DEMOUNTABLE, ENG 1)
451AL 452AR
(b) FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENG 2)
461AL 462AR
(2) Put an ACCESS PLATFORM 1M(3 FT) in position.

4. Procedure

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

Subtask 30-21-49-210-075-A ** ON A/C NOT FOR ALL

A. Detailed Inspection of Engine Air Intake Ice Protection Ducts
(1) Clean the inspection parts and areas with a lint-free cotton cloth (Material No.PU1-0001) .
(2) Do a detailed visual inspection of the Nacelle Anti-Ice (NAI) ducts. Use the LIGHT SOURCE - INSPECTION, MIRROR - INSPECTION and MAGNIFYING GLASS POWER 10X.
(a) Remove the insulation covers (Ref. AMM TASK 30-21-49-000-807).
(b) Examine the insulation covers. Look for cracks and other damage. If you find damage, replace the part (Ref. AMM TASK 30-21-49-000-807) and (Ref. AMM TASK 30-21-49-400-807).
(c) Examine the connections of the upper and lower anti-ice valves to the NAI ducts.
1 Make sure that the upper and lower anti-ice valves and attaching hardware are in the correct condition.
(d) Examine the connection of the NAI sense tubes to the NAI ducts. Look for cracks, signs of leaks and other damage. If you find damage, replace the part (Ref. AMM TASK 30-21-49-000-807) and (Ref. AMM TASK 30-21-49-400-807).
(e) Examine the NAI ducts. Look for cracks, dents, signs of leaks and other damage. If you find damage, replace the part (Ref. AMM TASK 30-21-49-000-807) and (Ref. AMM TASK 30-21-49-400-807).
(f) Examine the connections of the NAI ducts. Look for cracks, signs of leaks and other damage. If you find damage, replace the part (Ref. AMM TASK 30-21-49-000-807) and (Ref. AMM TASK 30-21-49-400-807).
(g) Examine the link assemblies and the attaching hardware of the NAI ducts. Look for cracks, loose or missing fasteners and other damage. If you find damage, replace the part (Ref. AMM TASK 30-21-49-000-807) and (Ref. AMM TASK 30-21-49-400-807).
(h) Install the insulation covers (Ref. AMM TASK 30-21-49-400-807).
(i) Examine the insulation cover. See sheet 8, view K of the figure.

Nacelle Anti-Ice (NAI) Ducts ** ON A/C NOT FOR ALL

Make sure that the drain hole is on the bottom of the cover and is open. If the drain hole is not in the correct location or is not open, replace the insulation cover (Ref. AMM TASK 30-21-49-000-807) and (Ref. AMM TASK 30-21-49-400-807).

5. Close-up
Subtask 30-21-49-410-128-A ** ON A/C NOT FOR ALL

A. Close Access
(1) Make sure that the work area is clean and clear of tools and other items.
(2) Close the thrust reverser cowl-doors (Ref. AMM TASK 78-36-00-410-802):
(a) FOR [4020KM1] (POWER PLANT-DEMOUNTABLE, ENG 1)
451AL 452AR
(b) FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENG 2)
461AL 462AR

Subtask 30-21-49-440-076-A ** ON A/C NOT FOR ALL

B. Do the reactivation of the thrust reverser system after ground maintenance (Ref. AMM TASK 78-30-00-440-805).

Subtask 30-21-49-410-129-A ** ON A/C NOT FOR ALL

C. Close Access
(1) Close the fan cowl doors (Ref. AMM TASK 71-13-00-410-802):
(a) FOR [4020KM1] (POWER PLANT-DEMOUNTABLE, ENG 1)
437AL 438AR
(b) FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENG 2)
447AL 448AR
(2) Remove the access platform(s).
(3) Remove the WARNING NOTICE(S).

Subtask 30-21-49-865-118-A ** ON A/C NOT FOR ALL

D. 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)
122VU	ANTI ICE/ENG/1	1DN1	X10
FOR FIN: 4020KM2 (POWER PLANTDEMOUNTABLE, ENG 2)
122VU	ANTI ICE/ENG/2	1DN2	W10

Subtask 30-21-49-862-071-A ** ON A/C NOT FOR ALL

E. De-energize the ground service network
(Ref. AMM TASK 24-42-00-862-001).

[Rev.10 from 2021] 2026.04.01 00:30:15 UTC