W DOC AIRBUS | AMM A320F

Leak Test of the Wing Tanks - Without Fuel - Pressurized Air and Helium/Air Procedure (Surge Tank is not Included)

TASK 28-11-00-790-805-A
Leak Test of the Wing Tanks - Without Fuel - Pressurized Air and Helium/Air Procedure (Surge Tank is not Included)

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 YOU HAVE THE CORRECT FIRE FIGHTING EQUIPMENT AVAILABLE.
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 2M (6 FT)
No specific
AR
ACCESS PLATFORM 6M (20 FT)
No specific
AR
SAFETY BARRIER(S)
No specific
AR
WARNING NOTICE(S)
98D27803000000
1
LOCKING TOOL-FLAP SLAT LEVER,INT. POSITION
98D28004009000
2
FLOAT VALVE BLANK
98D28004010000
2
PUMP NRV BLANK
98D28204002000
2
CTR TANK VENT BLANK
DETHEBPATEX
2
HELITEST ATEX
DETHECPATEX
2
HELITEST ATEX
DETTPSDDAI01
2

MS21914-10
2

TPS100K
2
TANK PRESSURIZATION SYSTEM
 B. Work Zones and Access Panels
ZONE/ACCESS
ZONE DESCRIPTION
540
FUEL TANK
640
FUEL TANK
540AB, 640AB
 C. Referenced Information
REFERENCE
DESIGNATION
TASK 12-11-28-650-003-A
Pressure Refuel with Automatic Control
TASK 12-34-24-869-001-A
Aircraft Bonding and Grounding (Earthing) for the Refuel/Defuel or Oxygen Servicing Operations
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 27-50-00-866-008-A
Extension of the Flaps on the Ground
TASK 27-50-00-866-008-A-01
Extension of the Flaps/Slats on the Ground
TASK 27-50-00-866-009-A
Retraction of the Flaps on the Ground
TASK 27-50-00-866-009-A-01
Retraction of the Flaps/Slats on the Ground
TASK 27-80-00-866-004-A
Extending the Slats on the Ground
TASK 27-80-00-866-005-A
Retracting the Slats on the Ground
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 28-11-00-790-009-A
Leak Test of the Fuel Tanks - Without Fuel - Helium Procedure
TASK 28-12-41-200-003-A
Inspection of the Overpressure Protector
TASK 28-21-43-000-003-A
Removal of the Fuel-Pump Check-Valve
TASK 28-21-43-400-003-B
Installation of the Fuel-Pump Check-Valve
TASK 28-25-00-650-001-A
Pressure Defuel
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 31-60-00-860-001-A
EIS Start Procedure
TASK 31-60-00-860-002-A
EIS Stop Procedure
TASK 51-76-12-300-001-A
Local Repair of the Fuel Tank Sealant
TASK 57-27-11-000-001-A
Removal of the Access Panel
TASK 57-27-11-000-002-A
Removal of the Access Panel
TASK 57-27-11-400-001-A
Installation of the Access Panel
TASK 57-27-11-400-002-A
Installation of the Access Panel
F Leak Test of the Left Wing Tank - Without Fuel - Pressurized Air and Helium/Air Procedure ** ON A/C NOT FOR ALL
F Leak Test of the Left Wing Tank - Without Fuel - Pressurized Air and Helium/Air Procedure ** ON A/C NOT FOR ALL
F Leak Test of the Right Wing Tank - Without Fuel - Pressurized Air and Helium/Air Procedure ** ON A/C NOT FOR ALL
F Leak Test of the Right Wing Tank - Without Fuel - Pressurized Air and Helium/Air Procedure ** ON A/C NOT FOR ALL
3. Job Set-up
Subtask 28-11-00-941-122-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).
   (2) Put a WARNING NOTICE(S) in the cockpit to tell persons not to operate the flight controls.
   (3) Put the 98D27803000000 LOCKING TOOL-FLAP SLAT LEVER,INT. POSITION on the slat/flap control lever.
   (4) Put the SAFETY BARRIER(S) in position.
Subtask 28-11-00-860-135-A
B. Aircraft Maintenance Configuration
   (1) Make sure that the aircraft is grounded (earthed) correctly (Ref. AMM TASK 12-34-24-869-001).
   (2) Energize the aircraft electrical circuits
(Ref. AMM TASK 24-41-00-861-002).
   (3) In the cockpit:
     (a) On the panel 25VU, make sure that the APU MASTER SW P/BSW is in the off position (the ON legend is off).
     (b) On the panel 115VU, make sure that the ENG/MASTER 1 and ENG/MASTER 2 switches are in the OFF position.
     (c) On the panel 40VU, make sure that the X FEED P/BSW is released (the ON legend is off).
   (4) Do the EIS start procedure (ECAM only) (Ref. AMM TASK 31-60-00-860-001), then:
  • On the ECAM control panel (CP), push (in) the FUEL P/BSW
  • Make sure that the FUEL page shows on the ECAM lower display unit (DU).
   (5) On the ECAM lower DU, make sure that:
  • The engine LP valves are shown closed (amber cross-line)
  • The APU LP valve shows closed (green crossed line)
  • The X FEED valve shows closed (green crossed line).
   (6) On the refuel/defuel panel 800VU, make sure that:
  • The MODE SELECT switch is in the OFF and guarded position
  • All the REFUEL VALVE switches are in the SHUT position.
   (7) Defuel the applicable fuel tank(s) (Ref. AMM TASK 28-25-00-650-001).
   (8) Drain the remaining fuel from the applicable fuel tank(s) (Ref. AMM TASK 28-25-00-650-003).
   (9) Fully extend the flaps and the slats (Ref. AMM TASK 27-50-00-866-008) and (Ref. AMM TASK 27-80-00-866-004).
   (10) Make sure that the 98D27803000000 LOCKING TOOL-FLAP SLAT LEVER,INT. POSITION is installed on the slat/flap control lever.
   (11) Make sure that the applicable overpressure protector on each NACA inlet is serviceable (Ref. AMM TASK 28-12-41-200-003).
   (12) Make sure that the manhole access panels of all wing tanks are installed correctly (Ref. AMM TASK 57-27-11-400-001) and (Ref. AMM TASK 57-27-11-400-002).
   (13) Do the EIS stop procedure (Ref. AMM TASK 31-60-00-860-002).
   (14) De-energize the aircraft electrical circuits
(Ref. AMM TASK 24-41-00-862-002).
Subtask 28-11-00-010-095-A ** ON A/C NOT FOR ALL
C. Get Access
   (1) Put the ACCESS PLATFORM 2M (6 FT) in position below the access panel 540AB (640AB).
   (2) Put the ACCESS PLATFORM 6M (20 FT) in position below the access panels 540RB (640RB) and 550AB (650AB).
   (3) Remove the applicable access panels.
     (a) To get access to RIB bay 2-3, remove the access panel 540AB (640AB) (Ref. AMM TASK 57-27-11-000-001) (Ref. AMM TASK 28-10-00-910-002).
     (b) To get access to RIB bay 21-22 and 22-23 of the fuel tank, remove the access panels 540RB (640RB) and 550AB (650AB) (Ref. AMM TASK 57-27-11-000-002) (Ref. AMM TASK 28-10-00-910-002).
Subtask 28-11-00-010-095-B ** ON A/C NOT FOR ALL
C. Get Access
   (1) Put the ACCESS PLATFORM 2M (6 FT) in position below the access panel 540AB (640AB).
   (2) Put the ACCESS PLATFORM 6M (20 FT) in position below the access panel 550AB (650AB).
   (3) Remove the applicable access panels.
     (a) To get access to RIB bay 2-3, remove the access panel 540AB (640AB) (Ref. AMM TASK 57-27-11-000-001) (Ref. AMM TASK 28-10-00-910-002).
     (b) To get access to RIB bay 22-23 of the fuel tank, remove the access panel 550AB (650AB) (Ref. AMM TASK 57-27-11-000-002) (Ref. AMM TASK 28-10-00-910-002).
4. Procedure
Subtask 28-11-00-790-102-A ** ON A/C NOT FOR ALL
CAUTION: MAKE SURE THAT THE MAXIMUM PRESSURE IN THE TANK IS NOT MORE THAN 0.1378 BAR (2.0 PSI). THIS WILL PREVENT DAMAGE TO THE FUEL SYSTEM.
A. Leak Test of the Left Wing Tank - Without Fuel - Pressurized Air and Helium/Air Procedure
F Leak Test of the Left Wing Tank - Without Fuel - Pressurized Air and Helium/Air Procedure ** ON A/C NOT FOR ALL
NOTE: You can use the applicable items that follow to do the leak test:
   (1) Connect the compressed air supply to the control unit (5).
   (2) Connect the power supply and set the control unit (5) switch to the ON position.
   (3) Install the blanks on the open pipes or the ducts at RIB 22:
     (a) Install the 98D28004009000 FLOAT VALVE BLANK (1) on the vent box opening on RIB bay 22-23.
     (b) Install the 98D28204002000 CTR TANK VENT BLANK (2) on the open vent pipe on RIB bay 22-23.
     (c) Disconnect the scavenge line from RIB bay 21-22 (Ref. AMM TASK 28-21-43-000-003).
     (d) Install the MS21914-10 PLUG or the 98D28004010000 PUMP NRV BLANK (3) on fuel-pump check-valve 37QM at RIB 22.
   (4) Install the DETTPSDDAI01 DUMMY MANHOLE DOOR (4) on the opening of panel 540AB.
   (5) Connect the control unit (5) to the DETTPSDDAI01 DUMMY MANHOLE DOOR (4).
   (6) Do the air leak test as follows:
     (a) Operate the control unit (5) to start the air test.
NOTE: The system will automatically increase the pressure to 0.10 bar (1.5 psi).
     (b) When the pressure is 0.10 bar (1.5 psi), monitor the pressure in the tank for a period of 10 minutes.
     (c) If the pressure in the tank decreases to less than 0.09 bar (1.3 psi), find the exit point of the leak.
NOTE: The control unit (5) will supply air pressure to find the exit point of the leak.
     (d) Listen for the hissing sounds of the air pressure around the tank boundaries.
     (e) If the hissing sound is heard, repair the leak.
     (f) If the pressure in the tank is stable at 0.09 bar (1.3 psi), operate the control unit (5) to release the pressure from the tank.
     (g) Make sure that the pressure in the tank is back to the atmospheric pressure.
   (7) Do the air or helium leak test as follows:
     (a) Connect the helium supply to the control unit (5).
     (b) Set the control unit (5) to supply air and helium to the tank.
     (c) Operate the control unit (5) to start the test.
NOTE: The system will automatically increase the pressure to 0.10 bar (1.5 psi).
     (d) Wait for 10 minutes to let the helium mix with air in the tank. This will make sure that there is approximately 10 percent of helium and 90 percent of air in the tank.
     (e) Use the portable helium detector to find the leak point on the external surface of the tank:
NOTE: The fuel leak can move along the aircraft structure.
       1 If helium is available in the adjacent area, use compressed air to remove helium.
       2 Make sure that you find the exit point of the leak.
     (f) Make match mark on each exit point when you find them.
NOTE: This procedure is to find the source of a leak when you do a leak test.
NOTE: The exit point of leakage can be far from the source of the leak.
NOTE: Air or helium can leak through the system valves and can cause an effect on the test results.
     (g) Operate the control unit (5) to release the pressure from the tank.
     (h) Make sure that the pressure in the tank is fully released before you continue.
     (i) Get access to the applicable fuel tank (Ref. AMM TASK 28-10-00-910-002):
       1 Make sure that the remaining helium content in the tank is fully removed to prevent the background signal.
     (j) Do a leak test at each exit point where the mark was made (Ref. AMM TASK 28-11-00-790-009).
     (k) On the source of each leak:
       1 Do the necessary repair procedure (Ref. AMM TASK 51-76-12-300-001).
       2 Do step (7) again to make sure that the leak is repaired.
   (8) Disconnect the DETTPSDDAI01 DUMMY MANHOLE DOOR (4) from the control unit (5).
   (9) Remove the DETTPSDDAI01 DUMMY MANHOLE DOOR (4) from manhole opening 540AB.
   (10) Disconnect the compressed air supply and the helium supply from the control unit (5).
   (11) Remove the blanks from RIB 22 as follows:
     (a) Remove the 98D28004009000 FLOAT VALVE BLANK (1) from the vent box opening on RIB bay 22-23.
     (b) Remove the 98D28204002000 CTR TANK VENT BLANK (2) from the open vent pipe on RIB bay 22-23.
     (c) Remove the MS21914-10 PLUG or 98D28004010000 PUMP NRV BLANK (3) from fuel-pump check-valve 37QM at RIB 22:
       1 Connect the scavenge line to RIB bay 22-23 (Ref. AMM TASK 28-21-43-400-003).
Subtask 28-11-00-790-103-A ** ON A/C NOT FOR ALL
CAUTION: MAKE SURE THAT THE MAXIMUM PRESSURE IN THE TANK IS NOT MORE THAN 0.1378 BAR (2.0 PSI). THIS WILL PREVENT DAMAGE TO THE FUEL SYSTEM.
B. Leak Test of the Right Wing Tank - Without Fuel - Pressurized Air and Helium/Air Procedure
F Leak Test of the Right Wing Tank - Without Fuel - Pressurized Air and Helium/Air Procedure ** ON A/C NOT FOR ALL
NOTE: You can use the applicable items that follow to do the leak test:
   (1) Connect the compressed air supply to the control unit (5).
   (2) Connect the power supply and set the control unit (5) switch to the ON position.
   (3) Install the blanks on the open pipes and the ducts at RIB 22:
     (a) Install the 98D28004009000 FLOAT VALVE BLANK (1) on the vent box opening on RIB bay 22-23.
     (b) Install the 98D28204002000 CTR TANK VENT BLANK (2) on the open vent pipe on RIB bay 22-23.
     (c) Disconnect the scavenge line from RIB bay 21-22 (Ref. AMM TASK 28-21-43-000-003).
     (d) Install the MS21914-10 PLUG or the 98D28004010000 PUMP NRV BLANK (3) on fuel-pump check-valve 38QM at RIB 22.
   (4) Install the DETTPSDDAI01 DUMMY MANHOLE DOOR (4) on the opening of panel 640AB.
   (5) Connect the control unit (5) to the DETTPSDDAI01 DUMMY MANHOLE DOOR (4).
   (6) Do the air leak test as follows:
     (a) Operate the control unit (5) to start the air test.
NOTE: The system will automatically increase the pressure to 0.10 bar (1.5 psi).
     (b) When the pressure is 0.10 bar (1.5 psi), monitor the pressure in the tank for a period of 10 minutes.
     (c) If the pressure in the tank decreases to less than 0.09 bar (1.3 psi), find the exit point of the leak.
NOTE: The control unit (5) will supply air pressure to find the exit point of the leak.
     (d) Listen for the hissing sounds of the air pressure around the tank boundaries.
     (e) If the hissing sound is heard, repair the leak.
     (f) If the pressure in the tank is stable at 0.09 bar (1.3 psi), operate the control unit (5) to release the pressure from the tank.
     (g) Make sure that the pressure in the tank is back to the atmospheric pressure.
   (7) Do the air or helium leak test as follows:
     (a) Connect the helium supply to the control unit (5).
     (b) Set the control unit (5) to supply air and helium to the tank.
     (c) Operate the control unit (5) to start the test.
NOTE: The system will automatically increase the pressure to 0.10 bar (1.5 psi).
     (d) Wait for 10 minutes to let the helium mix with air in the tank. This will make sure that there is approximately 10 percent of helium and 90 percent of air in the tank.
     (e) Use the portable helium detector to find the leak point on the external surface of the tank:
NOTE: The fuel leak can move along the aircraft structure.
       1 If helium is available in the adjacent area, use compressed air to remove helium.
       2 Make sure that you find the exit point of the leak.
     (f) Make match mark on each exit point when you find them.
NOTE: This procedure is to find the source of a leak when you do a leak test.
NOTE: The exit point of leakage can be far from the source of the leak.
NOTE: Air or helium can leak through the system valves and can cause an effect on the test results.
     (g) Operate the control unit (5) to release the pressure from the tank.
     (h) Make sure that the pressure in the tank is fully released before you continue.
     (i) Get access to the applicable fuel tank (Ref. AMM TASK 28-10-00-910-002):
       1 Make sure that the remaining helium content in the tank is fully removed to prevent the background signal.
     (j) Do a leak test at each exit point where the mark was made (Ref. AMM TASK 28-11-00-790-009).
     (k) On the source of each leak:
       1 Do the necessary repair procedure (Ref. AMM TASK 51-76-12-300-001).
       2 Do step (7) again to make sure that the leak is repaired.
   (8) Disconnect the DETTPSDDAI01 DUMMY MANHOLE DOOR (4) from the control unit (5).
   (9) Remove the DETTPSDDAI01 DUMMY MANHOLE DOOR (4) from manhole opening of 640AB.
   (10) Disconnect the compressed air supply and the helium supply from the control unit (5).
   (11) Remove the blanks from RIB 22 as follows:
     (a) Remove the 98D28004009000 FLOAT VALVE BLANK (1) from the vent box opening on RIB bay 22-23.
     (b) Remove the 98D28204002000 CTR TANK VENT BLANK (2) from the open vent pipe on RIB bay 22-23.
     (c) Remove the MS21914-10 PLUG or 98D28004010000 PUMP NRV BLANK (3) from fuel-pump check-valve 38QM at RIB 22:
       1 Connect the scavenge line to RIB bay 22-23 (Ref. AMM TASK 28-21-43-400-003).
Subtask 28-11-00-790-102-B ** ON A/C NOT FOR ALL
CAUTION: MAKE SURE THAT THE MAXIMUM PRESSURE IN THE TANK IS NOT MORE THAN 0.1378 BAR (2.0 PSI). THIS WILL PREVENT DAMAGE TO THE FUEL SYSTEM.
C. Leak Test of the Left Wing Tank - Without Fuel - Pressurized Air and Helium/Air Procedure
F Leak Test of the Left Wing Tank - Without Fuel - Pressurized Air and Helium/Air Procedure ** ON A/C NOT FOR ALL
NOTE: You can use the applicable items that follow to do the leak test:
   (1) Connect the compressed air supply to the control unit (4).
   (2) Connect the power supply and set the control unit (4) switch to the ON position.
   (3) Install the blanks on the open pipes or the ducts at RIB 22:
     (a) Install the 98D28004009000 FLOAT VALVE BLANK (1) on the vent box opening on RIB bay 22-23.
     (b) Install the 98D28204002000 CTR TANK VENT BLANK (2) on the open vent pipe on RIB bay 22-23.
   (4) Install the DETTPSDDAI01 DUMMY MANHOLE DOOR (3) on the opening of panel 540AB.
   (5) Connect the control unit (4) to the DETTPSDDAI01 DUMMY MANHOLE DOOR (3).
   (6) Do the air leak test as follows:
     (a) Operate the control unit (4) to start the air test.
NOTE: The system will automatically increase the pressure to 0.10 bar (1.5 psi).
     (b) When the pressure is 0.10 bar (1.5 psi), monitor the pressure in the tank for a period of 10 minutes.
     (c) If the pressure in the tank decreases to less than 0.09 bar (1.3 psi), find the exit point of the leak.
NOTE: The control unit (4) will supply air pressure to find the exit point of the leak.
     (d) Listen for the hissing sounds of the air pressure around the tank boundaries.
     (e) If the hissing sound is heard, repair the leak.
     (f) If the pressure in the tank is stable at 0.09 bar (1.3 psi), operate the control unit (4) to release the pressure from the tank.
     (g) Make sure that the pressure in the tank is back to the atmospheric pressure.
   (7) Do the air or helium leak test as follows:
     (a) Connect the helium supply to the control unit (4).
     (b) Set the control unit (4) to supply air and helium to the tank.
     (c) Operate the control unit (4) to start the test.
NOTE: The system will automatically increase the pressure to 0.10 bar (1.5 psi).
     (d) Wait for 10 minutes to let the helium mix with air in the tank. This will make sure that there is approximately 10 percent of the helium and 90 percent of the air in the tank.
     (e) Use the portable helium detector to find the leak point on the external surface of the tank:
NOTE: The fuel leak can move along the aircraft structure.
       1 If helium is available in the adjacent area, use compressed air to remove helium.
       2 Make sure that you find the exit point of the leak.
     (f) Make match mark on each exit point when you find them.
NOTE: This procedure is to find the source of a leak when you do a leak test.
NOTE: The exit point of leakage can be far from the source of the leak.
NOTE: Air or helium can leak through the system valves and can cause an effect on the test results.
     (g) Operate the control unit (4) to release the pressure from the tank.
     (h) Make sure that the pressure in the tank is fully released before you continue.
     (i) Get access to the applicable fuel tank (Ref. AMM TASK 28-10-00-910-002):
       1 Make sure that the remaining helium content in the tank is fully removed to prevent the background signal.
     (j) Do a leak test at each exit point where the mark was made (Ref. AMM TASK 28-11-00-790-009).
     (k) On the source of each leak:
       1 Do the necessary repair procedure (Ref. AMM TASK 51-76-12-300-001).
       2 Do step (7) again to make sure that the leak is repaired.
   (8) Disconnect the DETTPSDDAI01 DUMMY MANHOLE DOOR (3) from the control unit (4).
   (9) Remove the DETTPSDDAI01 DUMMY MANHOLE DOOR (3) from manhole opening 540AB.
   (10) Disconnect the compressed air supply and the helium supply from the control unit (4).
   (11) Remove the blanks from RIB 22 as follows:
     (a) Remove the 98D28004009000 FLOAT VALVE BLANK (1) from the vent box opening on RIB bay 22-23.
     (b) Remove the 98D28204002000 CTR TANK VENT BLANK (2) from the open vent pipe on RIB bay 22-23.
Subtask 28-11-00-790-103-B ** ON A/C NOT FOR ALL
CAUTION: MAKE SURE THAT THE MAXIMUM PRESSURE IN THE TANK IS NOT MORE THAN 0.1378 BAR (2.0 PSI). THIS WILL PREVENT DAMAGE TO THE FUEL SYSTEM.
D. Leak Test of the Right Wing Tank - Without Fuel - Pressurized Air and Helium/Air Procedure
F Leak Test of the Right Wing Tank - Without Fuel - Pressurized Air and Helium/Air Procedure ** ON A/C NOT FOR ALL
NOTE: You can use the applicable items that follow to do the leak test:
   (1) Connect the compressed air supply to the control unit (4).
   (2) Connect the power supply and set the control unit (4) switch to the ON position.
   (3) Install the blanks on the open pipes or the ducts at RIB 22:
     (a) Install the 98D28004009000 FLOAT VALVE BLANK (1) on the vent box opening on RIB bay 22-23.
     (b) Install the 98D28204002000 CTR TANK VENT BLANK (2) on the open vent pipe on RIB bay 22-23.
   (4) Install the DETTPSDDAI01 DUMMY MANHOLE DOOR (3) on the opening of panel 640AB.
   (5) Connect the control unit (4) to the DETTPSDDAI01 DUMMY MANHOLE DOOR (3).
   (6) Do the air leak test as follows:
     (a) Operate the control unit (4) to start the air test.
NOTE: The system will automatically increase the pressure to 0.10 bar (1.5 psi).
     (b) When the pressure is 0.10 bar (1.5 psi), monitor the pressure in the tank for a period of 10 minutes.
     (c) If the pressure in the tank decreases to less than 0.09 bar (1.3 psi), find the exit point of the leak.
NOTE: The control unit (4) will supply air pressure to find the exit point of the leak.
     (d) Listen for the hissing sounds of the air pressure around the tank boundaries.
     (e) If the hissing sound is heard, repair the leak.
     (f) If the pressure in the tank is stable at 0.09 bar (1.3 psi), operate the control unit (4) to release the pressure from the tank.
     (g) Make sure that the pressure in the tank is back to the atmospheric pressure.
   (7) Do the air or helium leak test as follows:
     (a) Connect the helium supply to the control unit (4).
     (b) Set the control unit (4) to supply air and helium to the tank.
     (c) Operate the control unit (4) to start the test.
NOTE: The system will automatically increase the pressure to 0.10 bar (1.5 psi).
     (d) Wait for 10 minutes to let the helium mix with air in the tank. This will make sure that there is approximately 10 percent of helium and 90 percent of air in the tank.
     (e) Use the portable helium detector to find the leak point on external surface of the tank:
NOTE: The fuel leak can move along the aircraft structure.
       1 If helium is available in the adjacent area, use compressed air to remove helium.
       2 Make sure that you find the exit point of the leak.
     (f) Make match mark on each exit point when you find them.
NOTE: This procedure is to find the source of a leak when you do a leak test.
NOTE: The exit point of leakage can be far from the source of the leak.
NOTE: Air or helium can leak through the system valves and can cause an effect on the test results.
     (g) Operate the control unit (4) to release the pressure from the tank.
     (h) Make sure that the pressure in the tank is fully released before you continue.
     (i) Get access to the applicable fuel tank (Ref. AMM TASK 28-10-00-910-002):
       1 Make sure that the remaining helium content in the tank is fully removed to prevent the background signal.
     (j) Do a leak test at each exit points where the mark was made (Ref. AMM TASK 28-11-00-790-009).
     (k) On the source of each leak:
       1 Do the necessary repair procedure (Ref. AMM TASK 51-76-12-300-001).
       2 Do step (7) again to make sure that the leak is repaired.
   (8) Disconnect the DETTPSDDAI01 DUMMY MANHOLE DOOR (3) from the control unit (4).
   (9) Remove the DETTPSDDAI01 DUMMY MANHOLE DOOR (3) from manhole opening 640AB.
   (10) Disconnect the compressed air supply and the helium supply from the control unit (4).
   (11) Remove the blanks from RIB 22 as follows:
     (a) Remove the 98D28004009000 FLOAT VALVE BLANK (1) from the vent box opening on RIB bay 22-23.
     (b) Remove the 98D28204002000 CTR TANK VENT BLANK (2) from the open vent pipe on RIB bay 22-23.
5. Close-up
Subtask 28-11-00-410-094-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 applicable access panels:
     (a) Install the access panel 540AB (640AB) (Ref. AMM TASK 57-27-11-400-001).
     (b) Install the access panels 540RB (640RB) and 550AB (650AB) (Ref. AMM TASK 57-27-11-400-002).
Subtask 28-11-00-410-094-B ** 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 applicable access panels:
     (a) Install the access panel 540AB (640AB) (Ref. AMM TASK 57-27-11-400-001).
     (b) Install the access panel 550AB (650AB) (Ref. AMM TASK 57-27-11-400-002).
Subtask 28-11-00-860-136-A
B. Aircraft Maintenance Configuration
   (1) Refuel the applicable fuel tank(s) (Ref. AMM TASK 12-11-28-650-003).
   (2) If applicable, retract the flaps and the slats fully (Ref. AMM TASK 27-50-00-866-009) and (Ref. AMM TASK 27-80-00-866-005).
Subtask 28-11-00-942-125-A
C. Removal of Equipment
   (1) Remove the SAFETY BARRIER(S).
   (2) Remove the access platform(s).
   (3) Remove the WARNING NOTICE(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 06:17:02 UTC
"WTRUIB" 2025