Removal of the Pressure Switch

TASK 29-22-53-000-013-A
Removal of the Pressure Switch

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.

WARNING: MAKE SURE THAT THE TRAVEL RANGES OF THE FLIGHT CONTROLS SURFACES ARE CLEAR. MOVEMENT OF FLIGHT CONTROLS CAN CAUSE INJURY TO PERSONS AND/OR DAMAGE TO EQUIPMENT.

WARNING: MAKE SURE THAT THE GROUND SAFETY-LOCKS ARE IN POSITION ON THE LANDING GEAR. THIS WILL PREVENT UNWANTED MOVEMENT OF THE LANDING GEAR, AND THUS POSSIBLE INJURY TO PERSONS AND DAMAGE TO THE AIRCRAFT AND/OR EQUIPMENT.

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	CAP - BLANKING
No specific	2	CAP - PROTECTION
No specific	AR	SAFETY BARRIER(S)
No specific	AR	SAFETY CLIP - CIRCUIT BREAKER
No specific	2	WARNING NOTICE(S)

B. Work Zones and Access Panels

ZONE/ACCESS	ZONE DESCRIPTION
147BB, 147CB, 195BB

C. Referenced Information

REFERENCE	DESIGNATION
TASK 29-00-00-864-001-A	Put the Related Hydraulic System in the Depressurized Configuration before Maintenance Action
TASK 29-00-00-910-002-A	Safety Procedures of the Hydraulic System
TASK 29-14-00-614-001-A	Depressurization of the Hydraulic Reservoirs
TASK 29-22-00-869-005-A	Extension of the Ram Air Turbine (RAT) on the Ground
TASK 32-12-00-010-001-A	Open the Main Gear Doors for Access
RAT Pressure Switch

3. Job Set-up
Subtask 29-22-53-860-089-A

A. Aircraft Maintenance Configuration

WARNING: OBEY THE HYDRAULIC SAFETY PROCEDURES.

(1) Obey the hydraulic safety procedures (Ref. AMM TASK 29-00-00-910-002).
(2) As necessary, use the applicable SAFETY BARRIERS, specified by the operator's instructions and your local regulations.
(3) Put the WARNING NOTICE(S) in position to tell persons not to pressurize the Blue hydraulic system:

in the cockpit on the hydraulic section 40VU of the overhead panel,
on the ground service panel of the Blue hydraulic system.

(4) Make sure that the Blue hydraulic system is depressurized and put it in the maintenance configuration.
(Ref. AMM TASK 29-00-00-864-001).
(5) Depressurize the reservoir of the Blue hydraulic system (Ref. AMM TASK 29-14-00-614-001).

WARNING: MAKE SURE THAT THE RAT TRAVEL RANGE IS CLEAR BEFORE YOU EXTEND/RETRACT THE RAT.

(6) Extend the Ram Air Turbine (RAT) (Ref. AMM TASK 29-22-00-869-005).

Subtask 29-22-53-010-063-A

B. Get Access
(1) Open the access door 195BB.
(2) Open the left main gear door (Ref. AMM TASK 32-12-00-010-001).
(3) Remove the access panel 147BB.
(4) Remove the access panel 147CB.
(5) Remove the protective cover from the RAT compartment as follows:

RAT Pressure Switch

(a) Loosen the screws (2) from the quick-release fasteners (3).
(b) Remove the screw (5) from the protective cover (1).
(c) Remove the protective cover (1) from the RAT compartment (4).

Subtask 29-22-53-865-085-A

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

PANEL	DESIGNATION	FIN	LOCATION
** ON A/C NOT FOR ALL
49VU	HYD/RAT/CTL	2801GE	D14
** ON A/C NOT FOR ALL
49VU	HYD/RAT/CTL	2801GE	B13
** ON A/C ALL
106VU	CSM/G /EV/MAN/SPLY	6XE	B04
121VU	HYDRAULIC/RAT/SPLY/EXTN/SOL1	2803GE	P33

4. Procedure
Subtask 29-22-53-020-063-A

A. Removal of the Pressure Switch
(1) Disconnect the electrical connector (9).
(2) Put a CAP - PROTECTION on the disconnected electrical connectors.
(3) Cut, remove and discard the lockwire from the pressure switch (8).
(4) Remove the pressure switch (8).
(5) Remove and discard the packing (7).
(6) Put a CAP - BLANKING in the open port of the RAT actuator (6).

[Rev.10 from 2021] 2026.04.01 00:26:29 UTC