Pressurization Test for Air Leakage or Noise in a Specified Area at a Differential Pressure of 550 mbar (7.97 psi) (with the AIDS)

TASK 05-53-00-780-002-A-01
Pressurization Test for Air Leakage or Noise in a Specified Area at a Differential Pressure of 550 mbar (7.97 psi) (with the AIDS)

WARNING: DO NOT OPEN THE DOORS WHILE THE RED WARNING LIGHT FLASHES. IF THE RED WARNING LIGHT FLASHES, REMAINING PRESSURE CAN CAUSE THE DOOR TO OPEN SUDDENLY AND CAN:

KILL OR CAUSE SERIOUS INJURY TO PERSONS
CAUSE DAMAGE TO THE AIRCRAFT.

WARNING: THERE MUST BE TWO PERSONS IN THE COCKPIT DURING THE PRESSURIZATION TEST. IF A CHANGE IN PRESSURE HAS AN UNWANTED EFFECT (PAIN, NOISE IN THE EARS, HEADACHE, OR OTHER) ON ONE PERSON, THE OTHER PERSON CAN ADJUST THE PRESSURE TO AVOID INJURY.

WARNING: DO NOT OPEN OR GO NEAR PRESSURE-SEALED DOORS WHEN THE AIRCRAFT IS PRESSURIZED. A PRESSURE-SEALED DOOR THAT OPENS WHEN THE AIRCRAFT IS PRESSURIZED:

WILL CAUSE EXPLOSIVE DECOMPRESSION.
CAN KILL OR CAUSE INJURY TO PERSONS AND/OR CAUSE DAMAGE TO THE AIRCRAFT OR EQUIPMENT.

WARNING: MAKE SURE THAT:

ONLY THE PERSONS NECESSARY FOR THE PRESSURIZATION TEST ARE IN THE AIRCRAFT DURING THE TEST.
THE PERSONS IN THE AIRCRAFT ARE IN GOOD PHYSICAL CONDITION.

BE CAREFUL WHEN YOU CONTROL THE PRESSURE. SUDDEN CHANGES IN PRESSURE CAN CAUSE PAIN AND INJURY.

WARNING: DO NOT LET PERSONS WHO HAVE A COLD, EAR ACHE, SINUS PROBLEMS OR A DIFFERENT ILLNESS GO INTO THE AIRCRAFT DURING THE PRESSURIZATION TEST. THE PRESSURE CHANGES DURING THE PRESSURIZATION TEST CAN CAUSE INJURY OR DEATH.

1. Reason for the Job
To do a pressurization test at a maximum differential pressure
of 550 mbar (7.97 psi):

To find the accurate location of external air leakage not found at 280 mbar (4.06 psi)
If Airbus tells you to do it after a specified structural repair.

NOTE: There must be a minimum of three persons necessary to do this task.

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

REFERENCE	QTY	DESIGNATION
No specific	AR	SAFETY BARRIER(S)
No specific	AR	SAFETY CLIP - CIRCUIT BREAKER
No specific	AR	WARNING NOTICE(S)

B. Consumable Materials

REFERENCE	DESIGNATION
No specific	leak-detection soap solution

C. Work Zones and Access Panels

ZONE/ACCESS	ZONE DESCRIPTION
811

D. Referenced Information

REFERENCE	DESIGNATION
TASK 05-53-00-780-002-A	Pressurization Test for Air Leakage or Noise in a Specified Area at a Differential Pressure of 550 mbar (7.97 psi)
TASK 12-33-21-618-001-A-01	Pre-conditioning through the HP Ground Connection
TASK 12-33-21-618-001-A-02	Pre-conditioning with the APU
TASK 23-44-00-700-001-A	Operational Test of the Service Interphone
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 31-36-00-740-008-A	Access to the Parameter Call-Up Menus
TASK 31-60-00-860-001-A	EIS Start Procedure
TASK 31-60-00-860-002-A	EIS Stop Procedure
TASK 34-10-00-860-002-A	ADIRS Start Procedure
TASK 34-10-00-860-005-A	ADIRS Stop Procedure
TASK 35-12-41-000-002-A	Removal of the Full-Face/Quick-Donning Oxygen-Mask
TASK 35-12-41-400-002-A	Installation of the Full-Face/Quick-donning Oxygen-Mask
TASK 52-10-00-410-001-A	Closing of the Passenger/Crew Door
TASK 52-21-11-400-001-A	Installation of the Emergency Exit Hatch
TASK 52-22-00-410-001-A	Closing of the Emergency Exit Doors from the Passenger Compartment
TASK 52-22-00-410-802-A	Closing of the Overwing Emergency-Exit Door from the Passenger Compartment
TASK 52-30-00-860-002-A	Close the FWD or Aft Cargo-Compartment Door with the Yellow Electric Pump
TASK 52-30-00-860-008-A	Close the Bulk Cargo-Compartment Door
TASK 52-41-00-410-002-A	Close the Avionics Compartment Doors after Access
TASK 56-12-11-410-001-A	Closing of the Cockpit Sliding Windows
TASK 31-37-00-00	AIDS INPUT INTERFACE - DESCRIPTION AND OPERATION

3. Job Set-up
Subtask 05-53-00-865-072-A ** ON A/C NOT FOR ALL

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

PANEL	DESIGNATION	FIN	LOCATION
** ON A/C NOT FOR ALL
122VU	DOORS/PAX/MONG	1MQ	T13
** ON A/C NOT FOR ALL
122VU	RPCU	4HL	X23
** ON A/C NOT FOR ALL
122VU	DOORS CKPT LOCK	1MQ	T13
122VU	CKPT/OVRD SYS/SPLY	4MQ	S10
122VU	COCKPIT DOOR LOCK SYSTEM	1MQ	T13

Subtask 05-53-00-865-079-A ** ON A/C NOT FOR ALL

B. Make sure that this(these) circuit breaker(s) is(are) closed:

PANEL	DESIGNATION	FIN	LOCATION
** ON A/C NOT FOR ALL
121VU	EIS/SLIDES/ARM AND WARN/FLT	15WN	P11
121VU	EIS/SLIDES/ARM AND WARN/GND	13WN	P10

Subtask 05-53-00-860-057-C ** ON A/C NOT FOR ALL

C. Aircraft Configuration
(1) Put the SAFETY BARRIER(S) and the WARNING NOTICE(S) in position to keep persons out of the work area.
(2) Make sure that the static probe covers are not installed.
(3) Energize the aircraft electrical circuits
(Ref. AMM TASK 24-41-00-861-002).
(4) From the external surface, make sure that the avionics equipment ventilation operates correctly. If it does not operate correctly and stops during the test, it will be necessary to stop the test.
(5) We recommend that you remove the crew oxygen masks (Ref. AMM TASK 35-12-41-000-002).

NOTE: This test uses an absolute pressure higher than the cabin pressures you get during usual aircraft operations.
The crew masks have an aneroid capsule that is usually resistant to the absolute pressures you can get during this test.
But, to prevent high stress on the aneroid capsule, we recommend the removal of the crew oxygen masks.

(6) On AIR COND panel 30VU:

Make sure that the PACK 1 and PACK 2 pushbutton switches are pushed (the FAULT legends are on).

(7) On the CABIN PRESS section of panel 25VU:

Release the MODE SEL pushbutton switch (the MAN legend comes on).

(8) On the EXT LT section of panel 25VU:

Set the BEACON switch to ON.

(9) Do the EIS start procedure (upper ECAM DU and lower ECAM DU only)
(Ref. AMM TASK 31-60-00-860-001).
(10) On the lower ECAM display unit, on the CAB PRESS page:

Make sure that the outflow valve 10HL is in the fully open position.

(11) On the VENTILATION section of panel 22VU:

Release the EXTRACT pushbutton switch (the OVRD legend comes on).
Release the CAB FANS pushbutton switch (the OFF legend comes on).

(12) On the lower ECAM display unit, on the CAB PRESS page:

The skin air-inlet (INLET) and skin air-outlet (EXTRACT) valves are closed.

(13) Do the Air Data and Intertial Reference System (ADIRS) start procedure (Ref. AMM TASK 34-10-00-860-002).
(14) On the MCDU, get access to the AIDS: PARAM ALPHA CALL-UP page.
Enter the alpha call-up codes that follow: (Ref. AMM TASK 31-36-00-740-008)

PDC, (1), (2) to show the cabin differential pressure
VSCB, (1), (2) to show the cabin vertical speed
OVP, (1), (2) or OFVP, (1), (2) to show the outflow valve position.

NOTE: You can also see the outflow valve position on the CAB PRESS page of the lower ECAM display unit.

NOTE: The Alpha Call-Up list (Ref. AMM D/O 31-37-00-00) gives the correct Alpha Call-Up codes.

If the PDC or VSCB alpha call-up parameter is not available with the AIDS, do the pressurization with the tools to get the missing parameter (Ref. AMM TASK 05-53-00-780-002).
(15) Close and lock the cockpit sliding windows (Ref. AMM TASK 56-12-11-410-001).
(16) Close all the access doors to the pressurized area:

The emergency exit hatch (Ref. AMM TASK 52-21-11-400-001) (Ref. AMM D/O 52-22-00-41)
The bulk cargo-compartment door (if installed) (Ref. AMM TASK 52-30-00-860-008)
The forward and aft cargo-compartment doors (Ref. AMM TASK 52-30-00-860-002)
The passenger/crew doors (Ref. AMM TASK 52-10-00-410-001).

(17) Do an interphone communication test between the cockpit and the ground service personnel out of the closed area (Ref. AMM TASK 23-44-00-700-001).
(18) Pressurize the pneumatic system:

With the APU (Ref. AMM TASK 12-33-21-618-001) or
with the HP ground-air supply unit (Ref. AMM TASK 12-33-21-618-001).

(19) If access door 811 is open, close it (Ref. AMM TASK 52-41-00-410-002).

Subtask 05-53-00-860-057-E ** ON A/C NOT FOR ALL

(6) On AIR COND panel 30VU:

Make sure that the PACK 1 and PACK 2 pushbutton switches are pushed (the FAULT legends are on).

(7) On the CABIN PRESS section of panel 25VU:

Release the MODE SEL pushbutton switch (the MAN legend comes on).

(8) On the EXT LT section of panel 25VU:

Set the BEACON switch to ON.

(9) Do the EIS start procedure (upper ECAM DU and lower ECAM DU only)
(Ref. AMM TASK 31-60-00-860-001).
(10) On the lower ECAM display unit, on the CAB PRESS page:

Make sure that the outflow valve 10HL is in the fully open position.

(11) On the VENTILATION section of panel 22VU:

Release the EXTRACT pushbutton switch (the OVRD legend comes on).
Release the CAB FANS pushbutton switch (the OFF legend comes on).

(12) On the CARGO VENT section of panel 22VU:

Release the FWD ISOL VALVE pushbutton switch (the OFF legend comes on).

(13) On the lower ECAM display unit, on the CAB PRESS page:

The skin air-inlet (INLET) and skin air-outlet (EXTRACT) valves are closed.

(14) Do the Air Data and Intertial Reference System (ADIRS) start procedure (Ref. AMM TASK 34-10-00-860-002).
(15) On the MCDU, get access to the AIDS: PARAM ALPHA CALL-UP page.
Enter the alpha call-up codes that follow: (Ref. AMM TASK 31-36-00-740-008)

PDC, (1), (2) to show the cabin differential pressure
VSCB, (1), (2) to show the cabin vertical speed
OVP, (1), (2) or OFVP, (1), (2) to show the outflow valve position.

NOTE: You can also see the outflow valve position on the CAB PRESS page of the lower ECAM display unit.

NOTE: The Alpha Call-Up list (Ref. AMM D/O 31-37-00-00) gives the correct Alpha Call-Up codes.

If the PDC or VSCB alpha call-up parameter is not available with the AIDS, do the pressurization with the tools to get the missing parameter (Ref. AMM TASK 05-53-00-780-002).
(16) Close and lock the cockpit sliding windows (Ref. AMM TASK 56-12-11-410-001).
(17) Close all the access doors to the pressurized area:

The emergency exit hatch (Ref. AMM TASK 52-21-11-400-001) (Ref. AMM TASK 52-22-00-410-802)
The bulk cargo-compartment door (if installed) (Ref. AMM TASK 52-30-00-860-008)
The forward and aft cargo-compartment doors (Ref. AMM TASK 52-30-00-860-002)
The passenger/crew doors (Ref. AMM TASK 52-10-00-410-001).

(18) Do an interphone communication test between the cockpit and the ground service personnel out of the closed area (Ref. AMM TASK 23-44-00-700-001).
(19) Pressurize the pneumatic system:

With the APU (Ref. AMM TASK 12-33-21-618-001) or
With the HP ground-air supply-unit (Ref. AMM TASK 12-33-21-618-001).

(20) If access door 811 is open, close it (Ref. AMM TASK 52-41-00-410-002).

Subtask 05-53-00-860-057-F ** ON A/C NOT FOR ALL

(6) On AIR COND panel 30VU:

Make sure that the PACK 1 and PACK 2 pushbutton switches are pushed (the FAULT legends are on).

(7) On the CABIN PRESS section of panel 25VU:

Release the MODE SEL pushbutton switch (the MAN legend comes on).

(8) On the EXT LT section of panel 25VU:

Set the BEACON switch to ON.

(9) Do the EIS start procedure (upper ECAM DU and lower ECAM DU only)
(Ref. AMM TASK 31-60-00-860-001).
(10) On the lower ECAM display unit, on the CAB PRESS page:

Make sure that the outflow valve 10HL is in the fully open position.

(11) On the VENTILATION section of panel 22VU:

Release the EXTRACT pushbutton switch (the OVRD legend comes on).
Release the CAB FANS pushbutton switch (the OFF legend comes on).

(12) On the CARGO VENT section of panel 22VU:

Release the AFT ISOL VALVE pushbutton switch (the OFF legend comes on).

(13) On the lower ECAM display unit, on the CAB PRESS page:

The skin air-inlet (INLET) and skin air-outlet (EXTRACT) valves are closed.

PDC, (1), (2) to show the cabin differential pressure
VSCB, (1), (2) to show the cabin vertical speed
OVP, (1), (2) or OFVP, (1), (2) to show the outflow valve position.

NOTE: You can also see the outflow valve position on the CAB PRESS page of the lower ECAM display unit.

NOTE: The Alpha Call-Up list (Ref. AMM D/O 31-37-00-00) gives the correct Alpha Call-Up codes.

The emergency exit hatch (Ref. AMM TASK 52-21-11-400-001) (Ref. AMM D/O 52-22-00-41)
The bulk cargo-compartment door (if installed) (Ref. AMM TASK 52-30-00-860-008)
The forward and aft cargo-compartment doors (Ref. AMM TASK 52-30-00-860-002)
The passenger/crew doors (Ref. AMM TASK 52-10-00-410-001).

(18) Do an interphone communication test between the cockpit and the ground service personnel out of the closed area (Ref. AMM TASK 23-44-00-700-001).
(19) Pressurize the pneumatic system:

With the APU (Ref. AMM TASK 12-33-21-618-001) or
With the HP ground-air supply-unit (Ref. AMM TASK 12-33-21-618-001).

(20) If access door 811 is open, close it (Ref. AMM TASK 52-41-00-410-002).

Subtask 05-53-00-860-057-S ** ON A/C NOT FOR ALL

(6) On AIR COND panel 30VU:

Make sure that the PACK 1 and PACK 2 pushbutton switches are pushed (the FAULT legends are on).

(7) On the CABIN PRESS section of panel 25VU:

Release the MODE SEL pushbutton switch (the MAN legend comes on).

(8) On the EXT LT section of panel 25VU:

Set the BEACON switch to ON.

(9) Do the EIS start procedure (upper ECAM DU and lower ECAM DU only)
(Ref. AMM TASK 31-60-00-860-001).
(10) On the lower ECAM display unit, on the CAB PRESS page:

Make sure that the outflow valve 10HL is in the fully open position.

(11) On the VENTILATION section of panel 22VU:

Release the EXTRACT pushbutton switch (the OVRD legend comes on).
Release the CAB FANS pushbutton switch (the OFF legend comes on).

(12) On the CARGO HEAT section of panel 22VU:

Release the AFT ISOL VALVE pushbutton switch (the OFF legend comes on).

(13) On the lower ECAM display unit, on the CAB PRESS page:

The skin air-inlet (INLET) and skin air-outlet (EXTRACT) valves are closed.

PDC, (1), (2) to show the cabin differential pressure
VSCB, (1), (2) to show the cabin vertical speed
OVP, (1), (2) or OFVP, (1), (2) to show the outflow valve position.

NOTE: You can also see the outflow valve position on the CAB PRESS page of the lower ECAM display unit.

NOTE: The Alpha Call-Up list (Ref. AMM D/O 31-37-00-00) gives the correct Alpha Call-Up codes.

The emergency exit hatch (Ref. AMM TASK 52-21-11-400-001) or the emergency exit doors (Ref. AMM TASK 52-22-00-410-001) (Ref. AMM D/O 52-22-00-41)
The bulk cargo-compartment door (if installed) (Ref. AMM TASK 52-30-00-860-008)
The forward and aft cargo-compartment doors (Ref. AMM TASK 52-30-00-860-002)
The passenger/crew doors (Ref. AMM TASK 52-10-00-410-001).

(18) Do an interphone communication test between the cockpit and the ground service personnel out of the closed area (Ref. AMM TASK 23-44-00-700-001).
(19) Pressurize the pneumatic system:

With the APU (Ref. AMM TASK 12-33-21-618-001) or
With the HP ground-air supply-unit (Ref. AMM TASK 12-33-21-618-001).

(20) If access door 811 is open, close it (Ref. AMM TASK 52-41-00-410-002).

4. Procedure
Subtask 05-53-00-780-054-A ** ON A/C NOT FOR ALL

WARNING: DO NOT LET THE CABIN ALTITUDE CHANGE TOO QUICKLY. SUDDEN CHANGES IN PRESSURE CAN CAUSE INJURY TO PERSONS.

WARNING: MAKE SURE THAT THE DIFFERENTIAL PRESSURE IS NOT MORE THAN THE VALUE SPECIFIED FOR THIS TEST.

WARNING: DO NOT USE THE ECAM DISPLAYS TO READ THE CABIN PRESSURE PARAMETERS (CABIN DIFFERENTIAL PRESSURE, CABIN ALTITUDE, CABIN VERTICAL- SPEED) DURING THIS TEST. THE PRESSURES USED IN THIS TEST ARE MORE THAN THE MAXIMUM LIMIT OF THE RELATED PRESSURE SENSOR. WHEN THESE PRESSURES BECOME MORE THAN THE PRESSURE SENSOR LIMIT, ON THE ECAM DISPLAY:

THE CABIN DIFFERENTIAL PRESSURE INDICATION AND THE CABIN ALTITUDE INDICATION WILL CONTINUE TO SHOW THESE LIMIT VALUES.
THE CABIN VERTICAL-SPEED INDICATION IS NOT CORRECT.

IF YOU DO NOT KNOW THE CORRECT CABIN PRESSURE VALUES, YOU CAN MAKE UNWANTED CHANGES IN PRESSURE THAT CAN CAUSE INJURY.

WARNING: BEFORE YOU GO NEAR THE PRESSURE-SEALED DOOR TO DO THE LEAK CHECK, MAKE SURE THAT NO OTHER MAINTENANCE WORK IN THE AIRCRAFT WILL CAUSE THE DOOR TO OPEN. IF THE PRESSURE-SEALED DOOR OPENS WHILE YOU ARE NEAR IT, IT CAN KILL YOU OR CAUSE YOU INJURY.

A. Test at a Differential Pressure of 550 mbar (7.98 psi)

NOTE: This procedure uses the MAN V/S CTL switch on the CABIN PRESS section of panel 25VU to control the cabin pressure. This switch, which is spring-loaded to neutral, controls the outflow valve position:

UP: the outflow valve moves to the open position (the cabin pressure decreases)
DN: the outflow valve moves to the closed position (the cabin pressure increases).
We recommend to operate this switch quickly (do not hold the switch in the UP or DN position)
We recommend to monitor the cabin vertical-speed indication to prevent sudden changes in cabin pressure.

ACTION	RESULT
1.On AIR COND panel 30VU: Adjust the cabin temperature control as necessary.	On AIR COND panel 30VU: Make sure that the FAULT legends of the PACK 1 and PACK 2 pushbutton switches is off. Air blows into the fuselage.
2.On the CABIN PRESS section of panel 25VU: Set the MAN V/S CTL switch to DN and release it. The switch moves to the neutral position. Do this operation many times. This closes the outflow valve (OVP indication on the MCDU). Make sure that the cabin vertical speed is not more than 500 ft.min (152.40 m.min) (VSCB indication on the MCDU). Stop when you get a cabin differential pressure of 300 mbar (4.35 psi) (PDC indication on the MCDU).	On the MCDU (VSCB indication): The cabin vertical speed must not be more than 500 ft.min (152.40 m.min). On the MCDU (PDC indication): The cabin differential pressure increases to 300 mbar (4.35 psi). On the upper ECAM display unit: It is possible that the CAB PR EXCES RESIDUAL PR warning message comes into view. NOTE: This warning message can come into view when the cabin pressure is more than 2.5 mbar (0.04 psi), while the door red warning lights flash.
3.With the MAN V/S CTL switch in the UP or DN position, keep the differential pressure stable at 300 mbar (4.35 psi) for 15 minutes.	Tell the ground personnel to do a precheck of the repaired area. On the MCDU (VSCB indication): The cabin vertical speed is 0. On the MCDU (PDC indication): The cabin differential pressure is 300 mbar (4.35 psi).
4.Use the same procedure as in step 2 to increase the cabin differential pressure to 550 mbar (7.98 psi). Make sure that the cabin vertical speed is not more than 500 ft.min (152.40 m.min) (VSCB indication on MCDU).	On the MCDU (VSCB indication): The cabin vertical speed must not be more than 500 ft.min (152.40 m.min). On the MCDU (PDC indication): The cabin differential pressure increases to 550 mbar (7.98 psi).
5.With the MAN V/S CTL switch in the UP or DN position, keep the differential pressure stable at 550 mbar (7.98 psi).	On the MCDU (VSCB indication): The cabin vertical speed is 0. On the MCDU (PDC indication): The cabin differential pressure is 550 mbar (7.98 psi).
6.Apply the leak-detection soap solution to find leaks.	Record possible leaks.
7.On the CABIN PRESS section of panel 25VU: With the MAN V/S CTL switch, decrease the cabin differential pressure until you get a differential pressure of 0 psi. Make sure that the cabin vertical speed is not more than 500 ft.min (152.40 m.min) (VSCB indication on the MCDU).	On the MCDU (VSCB indication): The cabin vertical speed must not be more than 500 ft.min (152.40 m.min). On the MCDU (PDC indication): The cabin differential pressure decreases to 0.
8.After the cabin is fully depressurized, fully open the outflow valve (OVP indication on the MCDU).

5. Close-up
Subtask 05-53-00-865-073-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
122VU	DOORS/PAX/MONG	1MQ	T13
** ON A/C NOT FOR ALL
122VU	RPCU	4HL	X23
** ON A/C NOT FOR ALL
122VU	DOORS CKPT LOCK	1MQ	T13
122VU	CKPT/OVRD SYS/SPLY	4MQ	S10
122VU	COCKPIT DOOR LOCK SYSTEM	1MQ	T13

Subtask 05-53-00-860-058-A ** ON A/C NOT FOR ALL

B. Put the Aircraft back to its Initial Configuration
(1) Stop the APU (Ref. AMM TASK 12-33-21-618-001) or stop the HP ground-air supply-unit (Ref. AMM TASK 12-33-21-618-001).
(2) On the VENTILATION section of panel 22VU:

Push the EXTRACT pushbutton switch (the OVRD legend comes off).
Push the CAB FANS pushbutton switch (the OFF legend comes off).

(3) If the CARGO VENT or CARGO HEAT section is installed on panel 22VU:

If the AFT ISOL VALVE pushbutton switch is installed, push it (the OFF legend goes off).
If the FWD ISOL VALVE pushbutton switch is installed, push it (the OFF legend goes off).

(4) On the CABIN PRESS section of panel 25VU, push the MODE SEL pushbutton switch (the MAN legend comes off).
(5) On the EXT LT section of panel 25VU:

Set the BEACON switch to the OFF position.

(6) If you removed the crew oxygen masks, install them (Ref. AMM TASK 35-12-41-400-002).
(7) Put the aircraft back to its initial configuration.
(8) Do the ADIRS stop procedure (Ref. AMM TASK 34-10-00-860-005).
(9) Do the EIS stop procedure (Ref. AMM TASK 31-60-00-860-002).
(10) De-energize the aircraft electrical circuits
(Ref. AMM TASK 24-41-00-862-002).
(11) Remove the warning notices and the safety barriers.

[Rev.10 from 2021] 2026.03.31 22:52:09 UTC