Installation of the Overpressure Protector Outlet

TASK 28-12-46-400-001-A
Installation of the Overpressure Protector Outlet

WARNING: THIS PROCEDURE USES A FUEL SYSTEM ITEM THAT IS IN A CATEGORY KNOWN AS A CRITICAL DESIGN CONFIGURATION CONTROL LIMITATION (CDCCL). CDCCL IDENTIFIES AN ITEM THAT CAN BE THE SOURCE OF A POSSIBLE FUEL TANK IGNITION. YOU MUST KEEP ALL CDCCL ITEMS IN THE APPROVED CONFIGURATION. DAMAGE, WEAR OR CHANGES TO A CDCCL ITEM CAN CAUSE A POSSIBLE FUEL TANK EXPLOSION.

WARNING: BE CAREFUL WHEN YOU USE CONSUMABLE MATERIALS. OBEY THE MATERIAL MANUFACTURER'S INSTRUCTIONS AND YOUR LOCAL REGULATIONS.

WARNING: MAKE SURE THAT THE FLIGHT CONTROL SAFETY-LOCKS AND THE WARNING NOTICES ARE IN POSITION.

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.

ZONE: 540
ZONE: 640

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

REFERENCE	QTY	DESIGNATION
No specific	AR	ACCESS PLATFORM 5M (16 FT)- ADJUSTABLE
No specific	AR	SAFETY BARRIER(S)
No specific	AR	SCRAPER - NON METALLIC
No specific	Torque wrench: range to between 30 and 25 lbf.in (0.34 and 0.28 m.daN )
No specific	Torque wrench: range to between 80 and 70 lbf.in (0.90 and 0.79 m.daN )
No specific	Torque wrench: range to between 160 and 140 lbf.in (1.81 and 1.58 m.daN )

B. Consumable Materials

REFERENCE	DESIGNATION
(Material No.06HAA1)	Coating Sealant-Fuel Tank Brushable -
(Material No.06LCG9)	Non Hardening Jointing Putty-Medium Temp. Area - -
(Material No.08BAA9)	Non Aqueous Cleaner-General - -
(Material No.12ABE2)	Corrosion Preventive Compound-Water Displacing Oily Film System
(Material No.14SBA1)	Textile-Lint free Cotton -

C. Work Zones and Access Panels

ZONE/ACCESS	ZONE DESCRIPTION
540	FUEL TANK
640	FUEL TANK

D. Expendable Parts

FIG.ITEM	DESIGNATION	IPC-CSN
2	SEALING RING	AIPC 28-12-46-01-010

E. Referenced Information

REFERENCE	DESIGNATION
TASK 12-11-28-650-003-A	Pressure Refuel with Automatic Control
TASK 20-28-00-912-802-A	Electrical Bonding - General Maintenance Procedure
TASK 28-10-00-910-001-A	Safety Procedures When You Do Work in a Fuel Tank
TASK 28-10-00-910-002-A	Access to the Fuel Tanks and the Work Areas
TASK 28-25-00-650-001-A	Pressure Defuel
TASK 28-25-00-869-001-A	Fuel Transfer
TASK 57-55-11-400-004-A	Installation of the Flap Track Fairings Nos. 2, 3 and 4
Inner Cell Overpressure-Protector Outlet, 540HB(640HB) ** ON A/C NOT FOR ALL
Wing Tank Overpressure-Protector Outlet, 540PB(640PB) ** ON A/C NOT FOR ALL
Wing Tank Overpressure-Protector Outlet, 540PB(640PB) ** ON A/C NOT FOR ALL
Inner Cell Overpressure-Protector Outlet, 540HB(640HB) ** ON A/C NOT FOR ALL
Into and Out-of-Wind Dimensions ** ON A/C NOT FOR ALL

3. Job Set-up
Subtask 28-12-46-941-054-A

A. Safety Precautions

WARNING: BEFORE YOU DO WORK IN OR NEAR A FUEL TANK, MAKE SURE THAT YOU OBEY ALL THE SAFETY PROCEDURES. THIS WILL PREVENT INJURY TO PERSONS AND/OR DAMAGE TO THE AIRCRAFT.

(1) You must obey the fuel safety procedures when you do work in a fuel tank (Ref. AMM TASK 28-10-00-910-001) and (Ref. AMM TASK 28-10-00-910-002).
(2) Make sure that the SAFETY BARRIER(S) are in position.

Subtask 28-12-46-860-052-A

B. Aircraft Maintenance Configuration
(1) Make sure that the applicable fuel tank is defueled (Ref. AMM TASK 28-25-00-650-001).
(2) Make sure that the remaining fuel has been drained from the applicable fuel tank (Ref. AMM TASK 28-25-00-650-001).
(3) Make sure that the ACCESS PLATFORM 5M (16 FT)- ADJUSTABLE is below the applicable zone 540(640).

4. Procedure
Subtask 28-12-46-420-052-B

A. Preparation for Installation
(1) Examine the sealing ring (2) for damage. If necessary, remove and discard it.
(2) Install the new AIPC 28-12-46-01-010 SEALING RING (2):
(a) Remove the used sealant from the groove in the access panel (3) with a SCRAPER - NON METALLIC.
(b) Clean the groove in the access panel (3) with a Textile-Lint free Cotton - (Material No.14SBA1) made moist with Non Aqueous Cleaner-General - - (Material No.08BAA9)
(c) Apply a thin layer of Coating Sealant-Fuel Tank Brushable - (Material No.06HAA1) to the groove in the access panel (3).
(d) While the sealant is wet, put the new sealing ring (2), with the flat edge down, into the groove in the access panel (3).
(3) Clean the component interface and the adjacent areas with a Textile-Lint free Cotton - (Material No.14SBA1) made moist with Non Aqueous Cleaner-General - - (Material No.08BAA9) .
(4) Do an inspection of the component interfaces and the adjacent area.
(5) Remove the protective cover from the pressure relief outlet (1).
(6) Apply a thin layer of Non Hardening Jointing Putty-Medium Temp. Area - - (Material No.06LCG9) to the bolts (4). Apply to the shank, the threads and below the head of each bolt (4).

Subtask 28-12-46-420-050-A ** ON A/C NOT FOR ALL

B. Installation of the Overpressure-Protector Outlet
(1) Make sure that all of the bonding straps are correctly installed and attached (Ref. AMM TASK 20-28-00-912-802), before you install the access panel 540HB(640HB).
(2) Apply Corrosion Preventive Compound-Water Displacing Oily Film System (Material No.12ABE2) to the fastener bolt (4) holes.
(3) Put the access panel (3) in position.

CAUTION: YOU MUST REMOVE AND INSTALL THE BOLTS IN THE SPECIFIED SEQUENCE. THIS WILL PREVENT DAMAGE TO THE ACCESS PANEL.

(4) Install the bolts (4) and TORQUE in the sequence A thru AB, in two steps, to these values:
(a) Firstly to between 30 and 25 lbf.in (0.34 and 0.28 m.daN )

.
(b) Secondly to between 160 and 140 lbf.in (1.81 and 1.58 m.daN )

.
(5) Make sure that the access panel (3) is correctly bonded to the wing skin (5):

WARNING: THIS INSTRUCTION IS APPLICABLE TO A CRITICAL DESIGN CONFIGURATION CONTROL LIMITATION (CDCCL) ITEM. CAREFULLY OBEY ALL GIVEN INSTRUCTIONS WHEN YOU DO THIS STEP. IF YOU DO NOT OBEY THESE INSTRUCTIONS, A DANGEROUS CONDITION CAN OCCUR THAT CAN CAUSE A POSSIBLE FUEL TANK EXPLOSION.

(a) Do a bonding check between the access panel (3) and the wing skin (5) (Ref. AMM TASK 20-28-00-912-802). Make sure that the electrical resistance is less than 10 milliohms.
(6) Make sure that DIMENSION 'A' is 1.5 mm (0.0591 in.) +/- 1 mm (0.0394 in.).

Subtask 28-12-46-420-050-B ** ON A/C NOT FOR ALL

B. Installation of the Overpressure-Protector Outlet
(1) Make sure that all of the bonding straps are correctly installed and attached (Ref. AMM TASK 20-28-00-912-802), before you install the access panel 540PB(640PB).
(2) Apply Corrosion Preventive Compound-Water Displacing Oily Film System (Material No.12ABE2) to the fastener bolt (4) holes.
(3) Put the access panel (3) in position.

CAUTION: YOU MUST REMOVE AND INSTALL THE BOLTS IN THE SPECIFIED SEQUENCE. THIS WILL PREVENT DAMAGE TO THE ACCESS PANEL.

(4) Install the bolts (4) and TORQUE in the sequence A thru AF,as follows:
(a) Initially, to between 30 and 25 lbf.in (0.34 and 0.28 m.daN )

.
(b) Finally, to between 80 and 70 lbf.in (0.90 and 0.79 m.daN )

.
(5) Make sure that the access panel (3) is correctly bonded to the wing skin (5):

Into and Out-of-Wind Dimensions ** ON A/C NOT FOR ALL

(a) Along the long axis, between +/- 0.6 mm (0.024 in.).
(b) Along the short axis for a distance of approximately 100 mm (3.937 in.), between +/- 0.3 mm (0.012 in.).

Subtask 28-12-46-420-050-C ** ON A/C NOT FOR ALL

B. Installation of the Overpressure-Protector Outlet

CAUTION: MAKE SURE THAT THE VORTEX GENERATOR IS IN GOOD CONDITION AND INSTALLED ON THE ACCESS PANEL.

(1) Make sure that all the bonding straps are correctly installed before you install the access panel (3) (Ref. AMM TASK 20-28-00-912-802).
(2) Apply the Corrosion Preventive Compound-Water Displacing Oily Film System (Material No.12ABE2) to the bolt (4) holes.
(3) Put the access panel (3) in position and loosely install the bolts (4).

CAUTION: YOU MUST REMOVE AND INSTALL THE BOLTS IN THE SPECIFIED SEQUENCE. THIS WILL PREVENT DAMAGE TO THE ACCESS PANEL.

(4) TORQUE the bolts (4) in the sequence A thru AB as follows:
(a) Initially, to between 30 and 25 lbf.in (0.34 and 0.28 m.daN )

.
(b) Finally, to between 160 and 140 lbf.in (1.81 and 1.58 m.daN )

.
(5) Make sure that the access panel (3) is correctly bonded to the wing skin (5):

(a) Do a bonding check between the access panel (3) and the wing skin (5) (Ref. AMM TASK 20-28-00-912-802).
(b) Make sure that the electrical resistance is less than 10 milliohms.
(6) Make sure that the DIMENSION 'A' is between 0.5 mm (0.020 in.) and 2.5 mm (0.098 in.).

Subtask 28-12-46-420-050-D ** ON A/C NOT FOR ALL

B. Installation of the Overpressure-Protector Outlet

CAUTION: MAKE SURE THAT THE VORTEX GENERATOR IS IN GOOD CONDITION AND INSTALLED ON THE ACCESS PANEL.

CAUTION: YOU MUST REMOVE AND INSTALL THE BOLTS IN THE SPECIFIED SEQUENCE. THIS WILL PREVENT DAMAGE TO THE ACCESS PANEL.

(4) TORQUE the bolts (4) in the sequence A thru AF as follows:
(a) Initially, to between 30 and 25 lbf.in (0.34 and 0.28 m.daN )

.
(b) Finally, to between 80 and 70 lbf.in (0.90 and 0.79 m.daN )

.
(5) Make sure that the access panel (3) is correctly bonded to the wing skin (5):

Into and Out-of-Wind Dimensions ** ON A/C NOT FOR ALL

(a) Along the long axis, between +/- 0.6 mm (0.024 in.).
(b) Along the short axis for a distance of approximately 100 mm (3.937 in.), between +/- 0.3 mm (0.012 in.).

Subtask 28-12-46-650-051-A

C. Preparation For Test
(1) Refuel the applicable fuel tank to high level (Ref. AMM TASK 12-11-28-650-003).

Subtask 28-12-46-790-050-A

D. Leak Test
(1) Examine the access panel joint for leaks.
Make sure there are no leaks.

Subtask 28-12-46-420-055-A ** ON A/C NOT FOR ALL

E. Installation of the Flap Track Fairing
(1) Install the forward and the aft fixed fairings from flap track No. 4 (Ref. AMM TASK 57-55-11-400-004).

5. Close-up
Subtask 28-12-46-650-054-A

A. Fuel Configuration
(1) Refuel, defuel or transfer fuel as necessary (Ref. AMM TASK 12-11-28-650-003), (Ref. AMM TASK 28-25-00-650-001) or (Ref. AMM TASK 28-25-00-869-001).

Subtask 28-12-46-942-051-A

B. Removal of Equipment
(1) Make sure that the work area is clean and clear of tools and other items.
(2) Remove the safety barriers.
(3) Remove the access platform(s).
(4) Remove the ground support and maintenance equipment, the special and standard tools and all other items.

[Rev.10 from 2021] 2026.04.02 07:01:34 UTC