Installation of the NACA Vent Intake

TASK 28-12-47-400-001-A
Installation of the NACA Vent Intake

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.

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 4M (13 FT)
No specific	AR	CONTAINER 20L (5 USGAL)
No specific	1	LIGHT SOURCE - SPARK-PROOF
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 100 and 90 lbf.in (1.13 and 1.02 m.daN )

B. Consumable Materials

REFERENCE	DESIGNATION
(Material No.01ABA1)	Turbine Fuel-- Kerosene -
(Material No.03FAB1)	Mineral Oil base Grease-- Vaseline or Petrolatum -
(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
550BB, 650BB

D. Expendable Parts

FIG.ITEM	DESIGNATION	IPC-CSN
10	TIE	AIPC 28-12-05-34-010
12	ORING	AIPC 28-12-05-34-140
17	RING	AIPC 28-12-47-01-010
12	ORING	AIPC 28-12-85-34-200

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 28-25-00-650-003-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
TASK 57-27-11-000-002-A	Removal of the Access Panel
TASK 57-27-11-400-002-A	Installation of the Access Panel
NACA Vent Intake ** ON A/C NOT FOR ALL
NACA Vent Intake Door Installation Details ** ON A/C NOT FOR ALL
NACA Vent Intake ** ON A/C NOT FOR ALL
NACA Vent Intake Door Installation Details ** ON A/C NOT FOR ALL
Warning Placards on the NACA Vent Intake ** ON A/C NOT FOR ALL

3. Job Set-up
Subtask 28-12-47-941-051-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 (Ref. AMM TASK 28-10-00-910-001) when you do work in a fuel tank.
(2) Make sure that the SAFETY BARRIER(S) are in position.

Subtask 28-12-47-860-050-A

B. Aircraft Maintenance Configuration
(1) Make sure that the ACCESS PLATFORM 4M (13 FT) is below the applicable zone 550(650).
(2) Make sure that the applicable access panel 550BB(650BB) is removed (Ref. AMM TASK 28-10-00-910-002) (Ref. AMM TASK 57-27-11-000-002).

4. Procedure
Subtask 28-12-47-420-052-B ** ON A/C NOT FOR ALL

A. Preparation for Installation
(1) Examine the sealing ring (17) for damage, if necessary replace the sealing ring (17) as follows:
(a) Remove and discard the sealing ring (17).
(b) Remove the used sealant from the groove in the NACA vent intake (16) with a SCRAPER - NON METALLIC.
(c) Clean the groove in the NACA vent intake (16) with a Textile-Lint free Cotton - (Material No.14SBA1) made moist with Non Aqueous Cleaner-General - - (Material No.08BAA9) .
(d) Apply a thin layer of Coating Sealant-Fuel Tank Brushable - (Material No.06HAA1) to the groove for the sealing ring (17) in the NACA vent intake (16).
(e) While the Coating Sealant-Fuel Tank Brushable - (Material No.06HAA1) is wet:
1 Put the new AIPC 28-12-47-01-010 RING (17) (with the flat edge down) in the groove in the NACA vent intake (16).
2 Remove unwanted Coating Sealant-Fuel Tank Brushable - (Material No.06HAA1) from the face of the NACA vent intake (16).
(2) Clean the component interfaces and the adjacent area with a Textile-Lint free Cotton - (Material No.14SBA1) made moist with Non Aqueous Cleaner-General - - (Material No.08BAA9) .
(3) Do an inspection of the component interfaces and the adjacent area.
(4) Make sure that the parts retained from the removed component are clean and in the correct condition.
(5) Apply a thin layer of Non Hardening Jointing Putty-Medium Temp. Area - - (Material No.06LCG9) to the bolts (15). Apply to the shank, the threads and below the head of each bolt (15).

Subtask 28-12-47-420-052-C ** ON A/C NOT FOR ALL

A. Preparation for Installation
(1) Use a LIGHT SOURCE - SPARK-PROOF to internally examine the NACA vent intake (16) and elbow duct assembly (11). Make sure that there is no sign of unwanted material in these components. If unwanted material is found, remove it.
(2) Examine the sealing ring (17) for damage, if necessary replace the sealing ring (17) as follows:
(a) Remove and discard the sealing ring (17).
(b) Remove the used sealant from the groove in the NACA vent intake (16) with a SCRAPER - NON METALLIC.
(c) Clean the groove in the NACA vent intake (16) with a Textile-Lint free Cotton - (Material No.14SBA1) made moist with Non Aqueous Cleaner-General - - (Material No.08BAA9) .
(d) Apply a thin layer of Coating Sealant-Fuel Tank Brushable - (Material No.06HAA1) to the groove for the sealing ring (17) in the NACA vent intake (16).
(e) While the Coating Sealant-Fuel Tank Brushable - (Material No.06HAA1) is wet:
1 Put the new AIPC 28-12-47-01-010 RING (17) (with the flat edge down) in the groove in the NACA vent intake (16).
2 Remove unwanted Coating Sealant-Fuel Tank Brushable - (Material No.06HAA1) from the face of the NACA vent intake (16).
(3) Clean the component interfaces and the adjacent area 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) Make sure that the parts retained from the removed component are clean and in the correct condition.
(6) Apply a thin layer of Non Hardening Jointing Putty-Medium Temp. Area - - (Material No.06LCG9) to the bolts (15). Apply to the shank, the threads and below the head of each bolt (15).

Subtask 28-12-47-420-050-A ** ON A/C NOT FOR ALL

B. Installation of the NACA Vent Intake
(1) Assemble the bolt (14), the nut (13) and one end of the bonding strap (9) to the NACA vent intake (16). Put the free end of the bonding strap (9) loosely in the end of the NACA vent intake (16).
(2) Apply Corrosion Preventive Compound-Water Displacing Oily Film System (Material No.12ABE2) to the bolt (15) holes.
(3) Install the NACA vent intake (16) as follows:
(a) Install the NACA vent intake (16) and secure it loosely with the bolts (15).
(b) TORQUE the bolts (15) in the sequence A thru AF, in two steps, as follows:

CAUTION: YOU MUST TIGHTEN AND TORQUE THE BOLTS IN THE CORRECT SEQUENCE TO PREVENT DAMAGE TO THE COMPONENTS.

1 Firstly to between 30 and 25 lbf.in (0.34 and 0.28 m.daN )

.
2 Secondly to between 100 and 90 lbf.in (1.13 and 1.02 m.daN )

.
(c) Make sure that the NACA vent intake (16) and the aircraft bottom skin are correctly aligned. The maximum in-to-wind or out-of-wind dimension is:

In areas less than 10 deg (10 deg) from the line of flight, 0.6 mm (0.0236 in.)
In areas greater than 10 deg (10 deg) from the line of flight, 0.3 mm (0.0118 in.).

(4) Do the bonding check as follows:

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) Make sure that one of the bolts (15) is correctly bonded (Ref. AMM TASK 20-28-00-912-802).
(5) Get access to the hole through access panel 550BB ( 650BB) and remove the free end of the bonding strap (9) from the NACA vent intake (16). Pull the free end of the bonding strap (9) through the duct hole in RIB23.
(6) Apply Turbine Fuel-- Kerosene - (Material No.01ABA1) or Mineral Oil base Grease-- Vaseline or Petrolatum - (Material No.03FAB1) to the AIPC 28-12-05-34-140 ORING (12).
(7) Install the new O-ring (12) on the elbow duct assembly (11).
(8) Install the elbow duct assembly (11) through RIB23 and into the NACA vent intake (16).
(9) Attach the elbow duct assembly (11) to the aircraft structure with the bolt (2) and the washer (1). Tighten the bolt (2).
(10) Attach the bonding strap (5) to the elbow duct assembly (11) with the bolt (4) and the nut (3) (Ref. AMM TASK 20-28-00-912-802).
(11) Attach the bonding straps (9) and (6) to the elbow duct assembly (11) with the bolt (8) and the nut (7) (Ref. AMM TASK 20-28-00-912-802).
(12) Safety the bonding strap (9) to the elbow duct assembly (11) with two new AIPC 28-12-05-34-010 TIE (10).

Subtask 28-12-47-420-050-B ** ON A/C NOT FOR ALL

B. Installation of the NACA Vent Intake

WARNING: MAKE SURE THAT THE WARNING/CAUTION PLACARDS ARE INSTALLED AND YOU CAN EASILY READ THEM. THESE PLACARDS TELL PERSONS THAT THERE IS A POSSIBLE LOW OXYGEN CONTENT IN:

THE AREA BEHIND THE ACCESS PANEL(S)
THE ADJACENT AREAS WHEN THE ACCESS PANEL(S) IS(ARE) OPEN.

IF THE PLACARDS ARE DAMAGED, MISSING OR PAINTED OVER, YOU MUST REPLACE THEM. THESE PLACARDS ARE RELATED TO A CRITICAL DESIGN CONFIGURATION CONTROL LIMITATION (CDCCL).

(1) Do a visual inspection to look for placards that are:

Damaged
Missing
Painted over.

(2) Make sure that you can easily read the placard message

Warning Placards on the NACA Vent Intake ** ON A/C NOT FOR ALL

(3) If the placards are damaged, missing, painted over or you cannot easily read them, replace them at the next maintenance opportunity.
(4) Assemble the bolt (14), the nut (13) and one end of the bonding strap (9) to the NACA vent intake (16). Put the free end of the bonding strap (9) loosely in the end of the NACA vent intake (16).
(5) Apply Corrosion Preventive Compound-Water Displacing Oily Film System (Material No.12ABE2) to the fastener bolt (18) holes.
(6) Install the NACA vent intake (16) as follows:
(a) Install the NACA vent intake (16) and secure it loosely with the bolts (15).
(b) TORQUE the bolts (15) in the sequence A thru AF, in two steps, as follows:

CAUTION: YOU MUST TIGHTEN AND TORQUE THE BOLTS IN THE CORRECT SEQUENCE TO PREVENT DAMAGE TO THE COMPONENTS.

1 Firstly to between 30 and 25 lbf.in (0.34 and 0.28 m.daN )

.
2 Secondly to between 100 and 90 lbf.in (1.13 and 1.02 m.daN )

.
(c) Make sure that the NACA vent intake (16) and the aircraft bottom skin are correctly aligned. The maximum in-to-wind or out-of-wind dimension is:

In areas less than 10 deg (10 deg) from the line of flight, 0.6 mm (0.0236 in.)
In areas greater than 10 deg (10 deg) from the line of flight, 0.3 mm (0.0118 in.).

(7) Do the bonding check as follows:

(a) Make sure that one of the bolts (15) is correctly bonded (Ref. AMM TASK 20-28-00-912-802).
(8) Get access to the hole through access panel 550BB ( 650BB) and remove the free end of the bonding strap (9) from the NACA vent intake (16). Pull the free end of the bonding strap (9) through the duct hole in RIB23.
(9) Apply Turbine Fuel-- Kerosene - (Material No.01ABA1) or Mineral Oil base Grease-- Vaseline or Petrolatum - (Material No.03FAB1) to the AIPC 28-12-05-34-140 ORING (12).
(10) Install the new O-ring (12) on the elbow duct assembly (11).
(11) Install the elbow duct assembly (11) through RIB23 and into the NACA vent intake (16).
(12) Attach the elbow duct assembly (11) to the aircraft structure with the bolt (2) and the washer (1). Tighten the bolt (2).
(13) Attach the bonding strap (5) to the elbow duct assembly (11) with the bolt (4) and the nut (3) (Ref. AMM TASK 20-28-00-912-802).
(14) Attach the bonding straps (9) and (6) to the elbow duct assembly (11) with the bolt (8) and the nut (7) (Ref. AMM TASK 20-28-00-912-802).
(15) Safety the bonding strap (9) to the elbow duct assembly (11) with two new AIPC 28-12-05-34-010 TIE (10).

Subtask 28-12-47-420-050-C ** ON A/C NOT FOR ALL

B. Installation of the NACA Vent Intake

WARNING: MAKE SURE THAT THE WARNING/CAUTION PLACARDS ARE INSTALLED AND YOU CAN EASILY READ THEM. THESE PLACARDS TELL PERSONS THAT THERE IS A POSSIBLE LOW OXYGEN CONTENT IN:

THE AREA BEHIND THE ACCESS PANEL(S)
THE ADJACENT AREAS WHEN THE ACCESS PANEL(S) IS(ARE) OPEN.

IF THE PLACARDS ARE DAMAGED, MISSING OR PAINTED OVER, YOU MUST REPLACE THEM. THESE PLACARDS ARE RELATED TO A CRITICAL DESIGN CONFIGURATION CONTROL LIMITATION (CDCCL).

(1) Do a visual inspection to look for placards that are:

Damaged
Missing
Painted over.

(2) Make sure that you can easily read the placard message.

Warning Placards on the NACA Vent Intake ** ON A/C NOT FOR ALL

(3) If the placards are damaged, missing, painted over or you cannot easily read them, replace them at the next maintenance opportunity.
(4) Assemble the bolt (14) and the nut (13) and one end of the bonding strap (9) to the NACA vent intake (16). Put the free end of the bonding strap (9) loosely in the end of the NACA vent intake (16).
(5) Apply Corrosion Preventive Compound-Water Displacing Oily Film System (Material No.12ABE2) to the fastener bolt (15) holes.
(6) Install the NACA vent intake (16) as follows:
(a) Install the NACA vent intake (16) and secure it loosely with the bolts (15).
(b) TORQUE the bolts (15) in the sequence A thru AF, in two steps, as follows:

CAUTION: YOU MUST TIGHTEN AND TORQUE THE BOLTS IN THE CORRECT SEQUENCE TO PREVENT DAMAGE TO THE COMPONENTS.

1 Firstly to between 30 and 25 lbf.in (0.34 and 0.28 m.daN )

.
2 Secondly to between 100 and 90 lbf.in (1.13 and 1.02 m.daN )

.
(c) Make sure that the NACA vent intake (16) and the aircraft bottom skin are correctly aligned. The maximum in-to-wind or out-of-wind dimension is:

In areas less than 10 deg (10 deg) from the line of flight, 0.6 mm (0.0236 in.)
In areas greater than 10 deg (10 deg) from the line of flight, 0.3 mm (0.0118 in.).

(7) Do the bonding check as follows:

(a) Make sure that one of the bolts (15) is correctly bonded (Ref. AMM TASK 20-28-00-912-802).
(8) Get access to the hole through access panel 550BB ( 650BB) and remove the free end of the bonding strap (9) from the NACA vent intake (16). Pull the free end of the bonding strap (9) through the duct hole in RIB23.
(9) Apply Turbine Fuel-- Kerosene - (Material No.01ABA1) or Mineral Oil base Grease-- Vaseline or Petrolatum - (Material No.03FAB1) to the AIPC 28-12-85-34-200 ORING (12).
(10) Install the new O-ring (12) on the elbow duct assembly (11).
(11) Install the elbow duct assembly (11) through RIB23 and into the NACA vent intake (16).
(12) Attach the elbow duct assembly (11) to the aircraft structure with the bolt (2) and the washer (1). Tighten the bolt (2).
(13) Attach the bonding strap (5) to the elbow duct assembly (11) with the bolt (4) and the nut (3) (Ref. AMM TASK 20-28-00-912-802).
(14) Attach the bonding straps (9) and (6) to the elbow duct assembly (11) with the bolt (8) and the nut (7) (Ref. AMM TASK 20-28-00-912-802).
(15) Safety the bonding strap (9) to the elbow duct assembly (11) with two new AIPC 28-12-05-34-010 TIE (10).

Subtask 28-12-47-410-050-A

C. Close Access
(1) Make sure that the work area is clean and clear of tools and other items.
(2) 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 fuel-tank access panels.
(3) Install the applicable access panel (Ref. AMM TASK 28-10-00-910-001) (Ref. AMM TASK 57-27-11-400-002):
- for the left wing 550BB
- for the right wing 650BB.

Subtask 28-12-47-860-051-A

D. Preparation For Test
(1) Refuel the applicable wing tank fully and keep the fuel tanker connected to the aircraft (Ref. AMM TASK 12-11-28-650-003).
(2) Put the CONTAINER 20L (5 USGAL) below the applicable water drain valve.
(3) On the panel 800VU:
(a) Put the MODE SEL switch to REFUEL.
(b) Put the applicable REFUEL VALVES switch to the OPEN position.
(c) Put the remaining REFUEL VALVES switches to the SHUT position.
(d) Put the TEST switch to the HI LVL position and keep it in this position.
(e) Make sure that the applicable HI LVL light goes out.
(4) Set the fuel tanker to its lowest flow rate and pressure. Make sure that fuel flows into the vent surge tank and out of the applicable water drain valve (21QM(22QM)) (Ref. AMM TASK 28-25-00-650-003).
(5) On the panel 800VU, put the applicable applicable wing tank REFUEL VALVES switch to the SHUT position. Make sure that the fuel flow from the applicable water drain valve decreases and then stops.
(6) Close the applicable water drain valve and remove the 97A28002117002 TOOL-PURGING (Ref. AMM TASK 28-25-00-650-003).
(7) On the panel 800VU, put the applicable wing tank REFUEL VALVES switch to the OPEN position.
(8) Let 50 l (13.2085 USgal) of fuel, measured at the tanker, flow into the vent surge tank.
(9) Stop the operation of the fuel tanker.
(10) On the panel 800VU:
(a) Release the TEST switch from the HI LVL position. Make sure that the applicable HI LVL lights come on.
(b) Put all of the REFUEL VALVES switches to the NORM and guarded position.

Subtask 28-12-47-790-050-A

E. Leak Test
(1) Examine the applicable NACA vent intake door panel for leaks.
Make sure there are no leaks.

5. Close-up
Subtask 28-12-47-650-051-A

A. Fuel Configuration
(1) Defuel or transfer fuel as necessary (Ref. AMM TASK 28-25-00-650-001) or (Ref. AMM TASK 28-25-00-869-001).

Subtask 28-12-47-942-050-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 WARNING NOTICE(S).
(4) Remove the access platform(s).
(5) Remove the ground support and maintenance equipment, the special and standard tools and all other items.

[Rev.10 from 2021] 2026.04.01 07:19:27 UTC