General Visual Inspection of APU Air Inlet Plenum and APU Air Intake (131-9(A))

TASK 49-16-00-210-802-A
General Visual Inspection of APU Air Inlet Plenum and APU Air Intake (131-9(A))

WARNING: MAKE SURE THAT YOU OBEY ALL THE WARNINGS AND ALL THE CAUTIONS INCLUDED IN THE REFERENCED PROCEDURES.

WARNING: LOCK THE MECHANISM OF THE ACCESS DOOR 316AR WITH THE PIP PIN WHEN YOU OPEN THE ACCESS DOOR. THIS WILL PREVENT INJURY.

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

WARNING: WHEN YOU USE COMPRESSED AIR:

USE THE CORRECT PROTECTION (FACE SHIELD OR GOGGLES)
DO NOT POINT THE AIRFLOW AT YOURSELF OR OTHER PERSONS.

LOOSE PARTICLES AND/OR HIGH PRESSURE AIR CAN CAUSE INJURY.

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

ZONE: 313
ZONE: 315

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 4M (13 FT)-ADJUSTABLE
No specific	AR	SAFETY CLIP - CIRCUIT BREAKER
No specific	1	WARNING NOTICE(S)

B. Consumable Materials

REFERENCE	DESIGNATION
(Material No.08AJA9)	Aqueous Cleaner-Turbine Engine Gas Path - Legacy

C. Work Zones and Access Panels

ZONE/ACCESS	ZONE DESCRIPTION
313	TAIL CONE APU AIR INTAKE AREA
315	TAIL CONE APU AND ACCESSORY COMPARTMENT
315AL, 316AR

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 29-00-00-864-001-A	Put the Related Hydraulic System in the Depressurized Configuration before Maintenance Action
TASK 49-16-00-100-005-A	Cleaning of the APU Air Intake (131-9(A))
TASK 52-41-00-010-001-A	Open the APU Doors for Access
TASK 52-41-00-410-001-A	Close the APU Doors after Access

3. Job Set-up
Subtask 49-16-00-860-082-A ** ON A/C NOT FOR ALL

A. Aircraft Maintenance Configuration
(1) Energize the ground service network
(Ref. AMM TASK 24-41-00-861-002).
(2) On the panel 25VU, press the APU MASTER SW pushbutton switch then make sure that the APU air intake flap has moved to the fully open position.
(3) Put a WARNING NOTICE(S) in the cockpit to tell persons not to start the APU.
(4) Make sure that the hydraulic systems are depressurized
(Ref. AMM TASK 29-00-00-864-001).

Subtask 49-16-00-865-100-A ** ON A/C NOT FOR ALL

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

PANEL	DESIGNATION	FIN	LOCATION
** ON A/C NOT FOR ALL
121VU	APU/APU/CTL	2KD	L42
121VU	APU/ECB/SPLY	1KD	L41

Subtask 49-16-00-010-074-A ** ON A/C NOT FOR ALL

C. Get Access
(1) Put an ACCESS PLATFORM 4M (13 FT)-ADJUSTABLE in position below the APU access doors 315AL and 316AR.
(2) Open the APU access doors 315AL and 316AR (Ref. AMM TASK 52-41-00-010-001).
(3) Set the light SW 11LJ to the ON position.

4. Procedure
Subtask 49-16-00-210-058-A ** ON A/C NOT FOR ALL

A. Inspection and Cleaning of the APU Inlet Plenum
(1) Do a visual inspection of the APU inlet plenum for dirt, debris, dust, sand, oil, combustible residues, grease, fungus growth and/or other contaminations.

Make sure that the APU inlet plenum is dry and clean.
If you find contamination do the following procedure:

(a) Clean the APU inlet plenum internally.

NOTE: Do not apply Aqueous Cleaner-Turbine Engine Gas Path - Legacy (Material No.08AJA9) to the pressure sensor (P2) opening.

Apply Aqueous Cleaner-Turbine Engine Gas Path - Legacy (Material No.08AJA9) mixed with clean drinking water with a spray bottle with a pressure between 2 bar (29.0075 psi) and 3 bar (43.5113 psi) on the inside of the composite inlet plenum.

(b) Let the mixture stay on the surface from 20 to 30 minutes to complete the cleaning procedure.
(c) Flush the cleaning solution from the surface of the inspection area with a hot-steam water-cleaner.

NOTE: Make sure that the water steam pressure is not more than 3 bar (43.5113 psi) and the water steam temperature is not higher than 130 deg.C (266.00 deg.F).
Do not direct the hot water steam on the external components of the APU.

(d) Inspect the surfaces after the cleaning procedure. If any contamination remains, repeat the cleaning procedure.
(e) Let the inspection area dry for 15 minutes.

Subtask 49-16-00-210-059-A ** ON A/C NOT FOR ALL

B. Do a visual inspection of the APU air intake.
(1) Visually check the APU air intake inner walls from both ending sides for dirt, debris, dust, sand, oil, combustible residues, grease, fungus growth and/or other contamination.
(a) Make sure that the APU air intake is dry and clean.

If you find contamination, clean the APU Air Intake (Ref. AMM TASK 49-16-00-100-005).

5. Close-up
Subtask 49-16-00-410-076-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) Set the LIGHT control switch 11LJ to the OFF position.
(3) Close the APU access doors 316AR 315AL (Ref. AMM TASK 52-41-00-410-001).
(4) Remove the access platform(s).
(5) Remove the WARNING NOTICE(S).

Subtask 49-16-00-865-101-A ** ON A/C NOT FOR ALL

B. 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
121VU	APU/APU/CTL	2KD	L42
121VU	APU/ECB/SPLY	1KD	L41

Subtask 49-16-00-860-083-A ** ON A/C NOT FOR ALL

C. Aircraft Maintenance Configuration
(1) On the panel 25VU, push the APU MASTER SW pushbutton and make sure that the APU air intake flap moves to the fully closed position.
(2) De-energize the ground service network
(Ref. AMM TASK 24-41-00-862-002).

[Rev.10 from 2021] 2026.04.01 12:42:02 UTC