Preservation of a Center Tank (Not in Use)

TASK 28-11-00-600-011-A
Preservation of a Center Tank (Not in Use)

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: OBEY THE FUEL SAFETY PROCEDURES.

WARNING: BE CAREFUL NOT TO GET AIRCRAFT FUEL IN YOUR MOUTH OR IN YOUR EYES. IF YOU GET FUEL ON YOUR SKIN OR ON YOUR CLOTHES, FLUSH IT IMMEDIATELY WITH WATER. IF NECESSARY, GET MEDICAL HELP. AIRCRAFT FUEL IS POISONOUS.

1. Reason for the Job
To remove collected water from a center tank not in use. This procedure will help prevent microbiological contamination of the center tank.

NOTE: This is not a mandatory task but is a recommended precaution to keep the center tank in good condition. It is recommended that you do this procedure at intervals of 100 days or 800 flight hours/400 flight cycles.

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

REFERENCE	QTY	DESIGNATION
No specific	1	ACCESS PLATFORM 2M (6 FT) - ADJUSTABLE
No specific	AR	SAFETY BARRIER(S)
No specific	AR	WARNING NOTICE(S)
98D27803500001	1	LOCKING TOOL ZERO POS

B. Work Zones and Access Panels

ZONE/ACCESS	ZONE DESCRIPTION
195BB, 196BB

C. Referenced Information

REFERENCE	DESIGNATION
TASK 12-11-28-650-003-A	Pressure Refuel with Automatic Control
TASK 12-32-28-281-001-A	Drain Water Content
TASK 28-25-00-650-003-A	To Drain Remaining Fuel from the Wing Tanks and the Center Tank
TASK 28-25-00-650-003-A-01	To Drain Remaining Fuel from the Wing Tanks and the Center Tank
TASK 28-25-00-869-001-A	Fuel Transfer

3. Job Set-up
Subtask 28-11-00-941-114-A

A. Safety Precautions
(1) Put the SAFETY BARRIER(S) in position.
(2) Install the 98D27803500001 LOCKING TOOL ZERO POS on the flap/slat control lever.
(3) Put WARNING NOTICE(S) in the cockpit to tell persons not to operate the flaps or slats.

Subtask 28-11-00-010-089-A

B. Get Access
(1) Put an ACCESS PLATFORM 2M (6 FT) - ADJUSTABLE in position below zone 190.
(2) Open the access panels 195BB and 196BB.

Subtask 28-11-00-860-117-A

C. Aircraft Maintenance Configuration
(1) Make sure that the wing tank(s) contain more than 3000 kg (6614 lb) of fuel (Ref. AMM TASK 12-11-28-650-003).
(2) Move approximately 2000 kg (4409 lb) of fuel from the applicable wing tank(s) to the center tank (Ref. AMM TASK 28-25-00-869-001).

4. Procedure
Subtask 28-11-00-680-051-A

A. Drain Collected Water from the Center Tank
(1) Wait approximately one hour to let all the water collect at the bottom of the center tank.
(2) Operate the water drain valves 94QM and 95QM to drain all the collected water from the center tank (Ref. AMM TASK 12-32-28-281-001).

Subtask 28-11-00-860-118-A

B. Aircraft Maintenance Configuration
(1) Move all the fuel from the center tank back into the applicable wing tank(s) (Ref. AMM TASK 28-25-00-869-001).
(2) Drain all the remaining fuel from the center tank (Ref. AMM TASK 28-25-00-650-003).

5. Close-up
Subtask 28-11-00-410-088-A

A. Close Access
(1) Make sure that the work area is clean and clear of tool(s) and other items.
(2) Close the access panels 195BB and 196BB.

Subtask 28-11-00-942-120-A

B. Removal of Equipment
(1) Remove the safety barriers.
(2) Remove the access platform(s).
(3) Remove the 98D27803500001 LOCKING TOOL ZERO POS from the flap/slat control lever.
(4) Remove the warning notice(s).
(5) Remove the ground support and maintenance equipment, the special and standard tools and all the other items.

[Rev.10 from 2021] 2026.04.02 07:02:44 UTC