Operational Test of the FWD Cargo-Compartment Outlet Isolation-Valve in the Ditching Configuration

TASK 21-28-00-710-004-A
Operational Test of the FWD Cargo-Compartment Outlet Isolation-Valve in the Ditching Configuration

ZONE: 132
FIN: 4HN ** ON A/C NOT FOR ALL

1. Reason for the Job
Refer to the MPD TASK: 212800-01
TBD
2. Job Set-up Information
A. Fixtures, Tools, Test and Support Equipment

REFERENCE	QTY	DESIGNATION
No specific	1	ACCESS PLATFORM 2M (6 FT)

B. Work Zones and Access Panels

ZONE/ACCESS	ZONE DESCRIPTION
132	FORWARD CARGO COMPARTMENT
132KW

C. 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 25-54-12-000-003-A	Removal of the Sidewall Panels in the Forward Cargo Compartment
TASK 25-54-12-400-003-A	Installation of the Sidewall Panels in the Forward Cargo Compartment
TASK 52-30-00-860-001-A	Open the FWD or Aft Cargo-Compartment Door with the Yellow Electric Pump
TASK 52-30-00-860-002-A	Close the FWD or Aft Cargo-Compartment Door with the Yellow Electric Pump

3. Job Set-up
Subtask 21-28-00-861-068-A ** ON A/C NOT FOR ALL

A. Energize the aircraft electrical circuits (Ref. AMM TASK 24-41-00-861-002).

Subtask 21-28-00-865-070-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
49VU	AIR COND/FWD CARGO/VENT/CTL & MONG	2HN	C08
49VU	AIR COND/TEMP CTL/SYS 1 CHAN B/28VDC	52HH	D08
122VU	FWD CARGO VENT AND HTG/FAN	1HN	T22
122VU	AIR COND/TEMP CTL SYS 2/CHAN A/115VAC	53HH	W22
122VU	AIR COND/TEMP CTL SYS 2/CHAN A/28VDC	55HH	W21
122VU	AIR COND/TEMP CTL SYS 1/CHAN A/115VAC	49HH	X22
122VU	AIR COND/TEMP CTL SYS 1/CHAN A/28VDC	51HH	X21
122VU	AIR COND/TEMP CTL SYS 2/CHAN B/28VDC	56HH	Y21
122VU	AIR COND/TEMP CTL SYS 2/CHAN B/115VAC	54HH	Y20
122VU	AIR COND/TEMP CTL SYS 1/CHAN B/115VAC	50HH	Y18

Subtask 21-28-00-010-063-A ** ON A/C NOT FOR ALL

C. Get Access
(1) Open the FWD cargo-compartment door 825 (Ref. AMM TASK 52-30-00-860-001).
(2) Put the ACCESS PLATFORM 2M (6 FT) position at the FWD cargo-compartment door 825.
(3) Remove the access panel 132KW (Ref. AMM TASK 25-54-12-000-003).

Subtask 21-28-00-860-053-A ** ON A/C NOT FOR ALL

D. Aircraft Maintenance Configuration
(1) On the overhead panel 22VU make sure that the white OFF light in the FWD ISOL VALVE pushbutton switch is on.

4. Procedure
Subtask 21-28-00-710-057-A ** ON A/C NOT FOR ALL

A. Do the Operational Test of the Outlet Isolation Valve in the Ditching Configuration

NOTE: During the test you must visually monitor the outlet isolation valve 4HN for correct movement sequence.

ACTION	RESULT
1.On the panel 22VU: push the FWD ISOL VALVE pushbutton switch.	On the panel 22VU: the white OFF light in the FWD ISOL VALVE pushbutton switch goes off.
	In the FWD cargo compartment: the inlet and outlet isolation valves open. the extraction fan operates after approx. 15 s.
2.On the panel 25VU: lift the black guard and push the DITCHING pushbutton switch.	On the panel 25VU: the white ON light in the DITCHING pushbutton switch comes on.
	In the FWD cargo compartment: the outlet isolation valve closes. the extraction fan stops.
3.On the panel 25VU: lift the black guard and push the DITCHING pushbutton switch.	On the panel 25VU: the white ON light in the DITCHING pushbutton switch goes off.
	In the FWD cargo compartment: the outlet isolation valve opens. the extraction fan operates after approx. 15 s.

5. Close-up
Subtask 21-28-00-410-064-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) Install the access panel 132KW (Ref. AMM TASK 25-54-12-400-003).
(3) Remove the access platform(s).
(4) Close the FWD cargo-compartment door 825 (Ref. AMM TASK 52-30-00-860-002).

Subtask 21-28-00-862-064-A ** ON A/C NOT FOR ALL

B. De-energize the aircraft electrical circuits (Ref. AMM TASK 24-41-00-862-002).

[Rev.10 from 2021] 2026.04.02 06:48:07 UTC