Installation of the VHF Antennas

TASK 23-12-11-400-001-A
Installation of the VHF Antennas

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

ZONE: 154
ZONE: 220
FIN: 4RC1
FIN: 4RC2

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

REFERENCE	QTY	DESIGNATION
No specific	1	ACCESS PLATFORM 6M (20 FT)
No specific	1	SCRAPER - NON METALLIC

B. Consumable Materials

REFERENCE	DESIGNATION
(Material No.04QAB2)	Coating_- Flexible Structure
(Material No.05RDA1)	Adhesive Film Tape-Masking - -
(Material No.06AAB1)	Polysulfide Sealant-General Purpose Fillet -
(Material No.06ABF1)	Polysulfide Sealant-Fuel Tank Quick Curing -
(Material No.06AEB2)	Polysulfide Sealant-Low Adhesion Fillet Structure
(Material No.08BAA9)	Non Aqueous Cleaner-General - -
(Material No.14DBB1)	Release Agent-- Liquid Wax -
(Material No.14SBA1)	Textile-Lint free Cotton -

C. Work Zones and Access Panels

ZONE/ACCESS	ZONE DESCRIPTION
154	U/FLOOR BAY OF AFT CARGO COMPARTMENT
220	FWD CAB UTILITY AREAS

D. Expendable Parts

FIG.ITEM	DESIGNATION	IPC-CSN
3	O-RING	AIPC 23-12-11-01-010

E. Referenced Information

REFERENCE	DESIGNATION
TASK 20-28-00-912-802-A	Electrical Bonding - General Maintenance Procedure
TASK 23-12-00-710-001-A	Operational Test of the Very High Frequency (VHF) System
TASK 23-12-00-710-802-A	Operational Test of the Multiple VHF Data Radio (MVDR) System
TASK 23-12-00-710-803-A	Operational Test of the Very High Frequency (VHF) System
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)
VHF Antennas ** ON A/C NOT FOR ALL
VHF Antennas ** ON A/C NOT FOR ALL
VHF Antennas ** ON A/C NOT FOR ALL

3. Job Set-up
Subtask 23-12-11-860-050-A

A. Aircraft Maintenance Configuration

WARNING: BEFORE YOU START WORK, YOU MUST PUT ON A SAFETY HARNESS AND ATTACH IT TO THE ACCESS PLATFORM. WITHOUT A SAFETY HARNESS, YOU CAN FALL. THIS CAN KILL YOU OR CAUSE YOU INJURY.

(1) Make sure that the aircraft electrical circuits are energized (Ref. AMM TASK 24-41-00-861-002).
(2) Make sure that the ACCESS PLATFORM 6M (20 FT) is in position at Zone 220.

Subtask 23-12-11-865-051-A

B. Make sure that this(these) circuit breaker(s) is(are) open, safetied and tagged:

PANEL	DESIGNATION	FIN	LOCATION
** ON A/C ALL
FOR FIN: 4RC1 (ANTENNAVHF, 1)
49VU	COM/VHF/1	2RC1	G09
** ON A/C NOT FOR ALL
FOR FIN: 4RC2 (ANTENNAVHF, 2)
121VU	COM NAV/VHF/2	2RC2	L04
** ON A/C NOT FOR ALL
121VU	COM/VHF/2	2RC2	L04

4. Procedure
Subtask 23-12-11-910-052-A

A. Preparation for Installation

WARNING: DO NOT GET THE FLUID ON YOUR SKIN OR IN YOUR EYES. IF YOU DO:

FLUSH IT AWAY WITH CLEAN WATER
GET MEDICAL AID.

(1) Do an inspection of the component interfaces and the adjacent area.
(2) Remove the sealant with a SCRAPER - NON METALLIC. Clean the fuselage structure with the Non Aqueous Cleaner-General - - (Material No.08BAA9) .
(3) Clean the component interface and/or the adjacent area with the Non Aqueous Cleaner-General - - (Material No.08BAA9) and the Textile-Lint free Cotton - (Material No.14SBA1) .
(4) Apply the Adhesive Film Tape-Masking - - (Material No.05RDA1) to:

the edge of the antenna (1)
the holes of the screws (6) or (7)
the hole for the antenna connector (2).

(5) Apply the Release Agent-- Liquid Wax - (Material No.14DBB1) to the bottom of the antenna (1).
(6) Apply the Polysulfide Sealant-Low Adhesion Fillet Structure (Material No.06AEB2) to the area of the fuselage adjacent to the antenna (1).

Subtask 23-12-11-420-051-A

B. Installation of the VHF Antennas 4RC1

WARNING: DO NOT GET THE FLUID ON YOUR SKIN OR IN YOUR EYES. IF YOU DO:

FLUSH IT AWAY WITH CLEAN WATER
GET MEDICAL AID.

(1) Remove the blanking caps from the coaxial cable connector (4) and the antenna connector (2).
(2) Remove the masking tape from:

The coaxial cable (5)
The holes of the screws (6)
The hole for the antenna connector (2).

(3) Make sure that the electrical connectors are clean and in the correct condition.
(4) Put the new AIPC 23-12-11-01-010 O-RING (3) in its correct position, on the base of the antenna (1).
(5) Connect the coaxial cable connector (4) to the antenna connector (2).
(6) Put the antenna (1) in position and install the screws (6) at the fuselage structure.
(7) Tighten the screws (6) diagonally.

NOTE: The antenna mounting screws (6) give the electrical bonding between the antenna (1) and the fuselage structure.

(8) Make sure that the bonding resistance between the antenna (1) and the fuselage structure is not more than 5 milliohms (Ref. AMM TASK 20-28-00-912-802).
(9) Remove the unwanted sealant with a SCRAPER - NON METALLIC.
(10) Clean the area with the Non Aqueous Cleaner-General - - (Material No.08BAA9) and a Textile-Lint free Cotton - (Material No.14SBA1) .
(11) Remove the masking tape from the base of the antenna (1).
(12) Apply the Polysulfide Sealant-General Purpose Fillet - (Material No.06AAB1) or Polysulfide Sealant-Fuel Tank Quick Curing - (Material No.06ABF1) to all the heads of the screws (6).
(13) Apply the Polysulfide Sealant-General Purpose Fillet - (Material No.06AAB1) or Polysulfide Sealant-Fuel Tank Quick Curing - (Material No.06ABF1) around the base of the antenna (1).
(14) Let the sealant become dry.
(15) Apply the Coating_- Flexible Structure (Material No.04QAB2) to all of the sealed heads of the screws (6) and the antenna base seal.

NOTE: It is not mandatory to paint the sealant around the base of the antenna and on the heads of the screws.

Subtask 23-12-11-420-054-A

C. Installation of the VHF Antenna 4RC2

WARNING: DO NOT GET THE FLUID ON YOUR SKIN OR IN YOUR EYES. IF YOU DO:

FLUSH IT AWAY WITH CLEAN WATER
GET MEDICAL AID.

(1) Remove the blanking caps from the coaxial cable connector (4) and the antenna connector (2).
(2) Remove the masking tape from:

The coaxial cable (5)
The holes of the screws (6) and (7)
The hole for the antenna connector (2).

(3) Make sure that the electrical connectors are clean and in the correct condition.
(4) Put the new AIPC 23-12-11-01-010 O-RING (3) in its correct position, on the base of the antenna (1).
(5) Connect the coaxial cable connector (4) to the antenna connector (2).
(6) Put the antenna (1) in position and install the screws (6) and (7) at the fuselage structure.
(7) Tighten the screws (6) and (7) diagonally.

NOTE: The antenna mounting screws (6) and (7) give the electrical bonding between the antenna (1) and the fuselage structure.

(8) Make sure that the bonding resistance between the antenna (1) and the fuselage structure is not more than 5 milliohms (Ref. AMM TASK 20-28-00-912-802).
(9) Remove the unwanted sealant with a SCRAPER - NON METALLIC.
(10) Clean the area with the Non Aqueous Cleaner-General - - (Material No.08BAA9) and a Textile-Lint free Cotton - (Material No.14SBA1) .
(11) Remove the masking tape from the base of the antenna (1).
(12) Apply the Polysulfide Sealant-General Purpose Fillet - (Material No.06AAB1) or Polysulfide Sealant-Fuel Tank Quick Curing - (Material No.06ABF1) to all the heads of the screws (6) and (7).
(13) Apply the Polysulfide Sealant-General Purpose Fillet - (Material No.06AAB1) or Polysulfide Sealant-Fuel Tank Quick Curing - (Material No.06ABF1) around the base of the antenna (1).
(14) Let the sealant become dry.
(15) Apply the Coating_- Flexible Structure (Material No.04QAB2) to all of the sealed heads of the screws (6), (7) and the antenna base seal.

NOTE: It is not mandatory to paint the sealant around the base of the antenna and on the heads of the screws.

Subtask 23-12-11-914-054-A

CAUTION: AT OR BEFORE THE END OF THE APPLICABLE TIME LIMIT (3 OR 10 DAYS), IT IS NECESSARY TO DO THE FULL INSTALLATION:

REMOVE THE ANTENNA
CLEAN THE FUSELAGE AND ANTENNA SURFACES AND REMOVE ALL SIGNS OF HUMIDITY
INSTALL THE ANTENNA WITH FULL INSTALLATION OF THE SEALANT.

IF YOU DO NOT DO THIS, THERE IS A RISK OF WATER INFILTRATION AND CORROSION.

D. Aircraft Antenna Sealant-Exemption

If it is not possible to apply sealant and to get the cure time, then:

The table that follows gives the time limits for sealant installation for VHF antenna.
These limits are adapted to:

Antenna installation configuration
Antenna location
Antenna sensitivity to water infiltration
Sealant availability

Configuration of antenna installation	If the Airline has sealant but does not want to wait until the sealant is cured	If the Airline has no sealant available
Sealant between the antenna and the fuselage (interposition sealant) sealing bead around the antenna sealant on the heads of the screws O-ring at the antenna connector level	Authorization to fly up to 10 days without sealing bead around the antenna if the interposition sealant was applied and the O-ring installed. Authorization to fly up to 10 days without sealant on the heads of the screws.	Authorization to fly up to 3 days without sealant (interposition sealant, sealant bead and sealant on the heads of the screws) if the O-ring is installed.

NOTE: When there is no sealing bead, there is a risk of aerodynamic noise.

Subtask 23-12-11-865-052-A

E. Remove the safety clip(s) and the tag(s) and close this(these) circuit breaker(s):

PANEL	DESIGNATION	FIN	LOCATION
** ON A/C ALL
49VU	COM/VHF/1	2RC1	G09
** ON A/C NOT FOR ALL
121VU	COM NAV/VHF/2	2RC2	L04
** ON A/C NOT FOR ALL
121VU	COM/VHF/2	2RC2	L04

Subtask 23-12-11-710-050-A ** ON A/C NOT FOR ALL

F. Test of the VHF System
(1) Do the operational test of the VHF system (Ref. AMM TASK 23-12-00-710-001).

Subtask 23-12-11-710-050-B ** ON A/C NOT FOR ALL

F. Test of the VHF System
(1) Do the operational test of the VHF system (Ref. AMM TASK 23-12-00-710-803).

Subtask 23-12-11-710-050-C ** ON A/C NOT FOR ALL

F. Test of the VHF System
(1) Do the operational test of the VHF system (Ref. AMM TASK 23-12-00-710-802).

5. Close-up
Subtask 23-12-11-860-054-B

A. Put the aircraft back to its initial configuration.
(1) Make sure that the work area is clean and clear of tools and other items.
(2) Remove the access platform(s).
(3) De-energize the aircraft electrical circuits
(Ref. AMM TASK 24-41-00-862-002).

[Rev.10 from 2021] 2026.04.01 04:04:13 UTC