Installation of the Total Pressure Tube (131-9(A))

TASK 49-51-17-400-003-A
Installation of the Total Pressure Tube (131-9(A))

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

1. Reason for the Job
Self explanatory
2. Job Set-up Information
A. Fixtures, Tools, Test and Support Equipment

REFERENCE	QTY	DESIGNATION
No specific	Torque wrench: range to between 55 and 45 lbf.in (0.62 and 0.51 m.daN )

B. Work Zones and Access Panels

ZONE/ACCESS	ZONE DESCRIPTION
315AL, 316AR

C. Expendable Parts

FIG.ITEM	DESIGNATION	IPC-CSN
7	PACKING	AIPC 49-21-09-04-040
2	PACKING	AIPC 49-21-09-04-160
7	PACKING	AIPC 49-21-84-30-470
2	PACKING	AIPC 49-21-84-30-520

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 29-00-00-864-001-A	Put the Related Hydraulic System in the Depressurized Configuration before Maintenance Action
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
Total Pressure Tube (131-9(A))

3. Job Set-up
Subtask 49-51-17-860-057-A ** ON A/C NOT FOR ALL

A. Aircraft Maintenance Configuration
(1) Energize the ground service network
(Ref. AMM TASK 24-42-00-861-001).
(2) On the panel 25VU, make sure that the APU MASTER SW p/bsw is OFF.
(3) Make sure that there is a warning notice 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 49-51-17-865-057-A ** ON A/C NOT FOR ALL

B. Make sure that this(these) circuit breaker(s) is(are) open, safetied and tagged:

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

Subtask 49-51-17-010-057-A ** ON A/C NOT FOR ALL

C. Get Access
(1) Make sure that the access platform is in position below the APU compartment.
(2) Make sure that the APU access doors are open (Ref. AMM TASK 52-41-00-010-001).
(3) Make sure that the LIGHT control SW 11LJ is set to the ON position.

4. Procedure
Subtask 49-51-17-420-052-A ** ON A/C NOT FOR ALL

A. Installation of the Total Pressure Tube
(1) Remove the PLUG-BLANKING from each disconnected line end.
(2) Install the new AIPC 49-21-09-04-160 PACKING (2) or AIPC 49-21-84-30-520 PACKING (2) and AIPC 49-21-09-04-040 PACKING (7) or AIPC 49-21-84-30-470 PACKING (7) on both sides of the tube (5).
(3) Connect the tube retainer (3) to the differential pressure transducer (1) and install the bolt (4).
(4) TORQUE the bolt (4) to between 55 and 45 lbf.in (0.62 and 0.51 m.daN )

.
(5) Connect the tube retainer (6) to the probe total pressure (9) and install the bolt (8).
(6) TORQUE the bolt (8) to between 55 and 45 lbf.in (0.62 and 0.51 m.daN )

5. Close-up
Subtask 49-51-17-410-053-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 SW 11LJ to the OFF position.
(3) Close the APU access doors 315AL 316AR (Ref. AMM TASK 52-41-00-410-001).
(4) Remove the access platform(s).

Subtask 49-51-17-865-058-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 49-51-17-860-058-A ** ON A/C NOT FOR ALL

C. Aircraft Maintenance Configuration
(1) Put the related hydraulic system in the pressurized configuration (Ref. AMM TASK 29-00-00-864-001).
(2) De-energize the ground service network
(Ref. AMM TASK 24-42-00-862-001).
(3) Remove the WARNING NOTICE(S).

[Rev.10 from 2021] 2026.04.01 01:31:01 UTC