Installation of the Weather-Radar Antenna Assembly

TASK 34-41-11-400-005-A
Installation of the Weather-Radar Antenna Assembly

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

WARNING: MOVE THE RADAR ANTENNA ASSEMBLY CAREFULLY TO PREVENT INJURY TO PERSONS AND DAMAGE TO EQUIPMENT. THE RADAR ANTENNA ASSEMBLY (ANTENNA/DRIVE) WEIGHS APPROXIMATELY 15kg (33lb).

CAUTION: DO NOT USE THE LOCALIZER ANTENNA AT THE BOTTOM OF THE RADOME AS A SUPPORT.

ZONE: 110
FIN: 11SQ ** ON A/C NOT FOR ALL
FIN: 7SQ ** ON A/C NOT FOR ALL

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	WARNING NOTICE(S)
No specific	Torque wrench: range to between 0.21 and 0.19 m.daN (18.58 and 16.81 lbf.in )
No specific	Torque wrench: range to between 0.25 and 0.20 m.daN (22.12 and 17.70 lbf.in )
No specific	Torque wrench: range to between 0.26 and 0.226 m.daN (23.01 and 20.00 lbf.in )
No specific	Torque wrench: range to between 3.87 and 3.22 m.daN (28.54 and 23.75 lbf.ft )

B. Consumable Materials

REFERENCE	DESIGNATION
(Material No.14QDC1)	Wire-Locking Dia: 0.5 mm (0.020 inch) CRES -
(Material No.14QFC1)	Wire-Locking Dia: 0.8 mm CRES -

C. Work Zones and Access Panels

ZONE/ACCESS	ZONE DESCRIPTION
110	RADOME (NOSE CONE TO FR 1)
110AL

D. Expendable Parts

FIG.ITEM	DESIGNATION	IPC-CSN
29	O-RING	AIPC 34-41-01-02-120
3	O-RING	AIPC 34-41-01-02-120
6	O-RING	AIPC 34-41-01-02-120
29	O-RING	AIPC 34-41-81-02-140
3	O-RING	AIPC 34-41-81-02-140
6	O-RING	AIPC 34-41-81-02-140

E. Referenced Information

REFERENCE	DESIGNATION
TASK 20-28-00-912-802-A	Electrical Bonding - General Maintenance Procedure
TASK 34-41-00-730-001-A	System Test of the Weather Radar
TASK 53-15-11-010-001-A	Opening of the Radome
TASK 53-15-11-410-001-A	Closing of the Radome
Weather-Radar Antenna Assembly ** ON A/C NOT FOR ALL
Radar Antenna ** ON A/C NOT FOR ALL
Weather-Radar Antenna Assembly ** ON A/C NOT FOR ALL

3. Job Set-up
Subtask 34-41-11-860-051-A ** ON A/C NOT FOR ALL

A. Aircraft Maintenance Configuration
(1) In the cockpit, put the WARNING NOTICE(S) on the center pedestal to tell the persons not to operate the weather radar system.
(2) Put the ACCESS PLATFORM 5M (16 FT)- ADJUSTABLE in position below the radome at zone 110.
(3) Open radome 110AL (Ref. AMM TASK 53-15-11-010-001).

Subtask 34-41-11-865-060-A ** ON A/C NOT FOR ALL

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

PANEL	DESIGNATION	FIN	LOCATION
** ON A/C NOT FOR ALL
121VU	COM NAV/RADAR/1	5SQ1	K13

4. Procedure
Subtask 34-41-11-420-056-A ** ON A/C NOT FOR ALL

A. Installation of the Antenna Assembly

NOTE: Two persons are necessary for the installation of the antenna drive. One person holds the antenna drive while the other person installs the bolts.

(1) If installed, do not remove the transparent plastic windows that are at:

The inlet of the antenna drive (13)
The interface between the antenna drive (13) and the antenna (18).

(2) Clean the component interfaces and the adjacent area.
(3) Do an inspection of the component interfaces and the adjacent area.
(4) Hold the antenna drive (13) in its position.
(5) Install the two top bolts (1) and the washers (2).
(6) Install the two bottom bolts (10) and the washers (9).
(7) TORQUE the bolts (1) and (10) to between 3.87 and 3.22 m.daN (28.54 and 23.75 lbf.ft )

.
(8) Make sure that the bonding contact resistance between the antenna drive (13) and the structure (7) is not more than five milliohms (Ref. AMM TASK 20-28-00-912-802).
(9) Remove the blanking caps from the electrical connectors (11) and (12) and the flanges of the waveguide (5).
(10) Installation of the waveguide (5).

CAUTION: BE CAREFUL WHEN HANDLING THE WAVEGUIDE AS DAMAGE CAN OCCUR IF IT IS BENT BEYOND THE MANUFACTURERS LIMITATIONS. ENSURE THAT NO DEBRIS ENTERS THE WAVEGUIDE FROM THE OPEN END(S) WHEN REMOVED.

(a) Install a new AIPC 34-41-01-02-120 O-RING (6) or a new AIPC 34-41-81-02-140 O-RING (6) in the correct position on the flange (ANT reference) of the waveguide (5).
(b) Put the flange (ANT reference) of the waveguide (5) in position on the antenna drive (13).
(c) Lock the quick-disconnect attach (4).
(d) Install a new AIPC 34-41-01-02-120 O-RING (29) or a new AIPC 34-41-81-02-140 O-RING (29) in the correct position on the flange of the waveguide (5).
(e) Connect the waveguide (5) to the flange (22).
(f) Install the four washers (24) and the four screws (23).
(g) TORQUE the screws to between 0.21 and 0.19 m.daN (18.58 and 16.81 lbf.in )

.
(h) Installation of the lockwire:

WARNING: USE PROTECTIVE GOGGLES AND GLOVES WHEN YOU REMOVE OR INSTALL LOCKWIRE. EACH TIME YOU CUT LOCKWIRE, REMOVE AND DISCARD IT IMMEDIATELY. LOOSE LOCKWIRE CAN CUT YOU OR MAKE YOU BLIND, AND/OR CAN CAUSE DAMAGE.

1 Safety the screws (23) with 14QDC1Wire-Locking Dia: 0.5 mm (0.020 inch) CRES -.
(i) Install the two half-bushings (28) and the clamp (27) on the waveguide.
(j) Put the clamp (27) in position and install the washer (25) and the screw (26).
(k) Tighten the screw (26).
(11) Connect the electrical connector(s) (11).

Subtask 34-41-11-420-057-A ** ON A/C NOT FOR ALL

B. Installation of the Antenna

NOTE: During the installation of the antenna, two persons are necessary. One person must hold the antenna and the other person must hold the position indicator (14) (to prevent damage to the drive caused by the fast movement of the counterbalance spring).

(1) Attach the antenna (18) to the ring mount (19) with the screws (15) and the lockwashers (16).
(2) Connect the flange of the wave guide (17) to the antenna (18).
(3) Install the screws (21) and the lockwashers (20).
(4) TORQUE the screws (15) and (21) to between 0.26 and 0.226 m.daN (23.01 and 20.00 lbf.in )

.
(5) Make sure that the antenna assembly turns correctly in azimuth and in elevation.
(6) Make sure that the locking device is installed on the elevation and azimuth switches (8) to prevent their operation.

Subtask 34-41-11-420-056-B ** ON A/C NOT FOR ALL

C. Installation of the Weather-Radar Antenna Assembly

NOTE: Two persons are necessary for the installation of the antenna drive. One person holds the antenna drive and the other person installs all the bolts.

(1) Do not remove the transparent plastic windows that are installed at:

The inlet of the antenna drive (1)
The interface between the antenna drive (1) and the antenna (17).

(2) Clean the component interfaces and the adjacent area.
(3) Do an inspection of the component interfaces and the adjacent area.
(4) Hold the antenna drive (1) in its position.
(5) Install the top bolts (5) and the washers (6). Make sure that they are sufficiently loose.
(6) Lift the antenna drive (1) up to the structure (7) and engage it on the top bolts (5).
(7) Make sure that the washers (6) are between the bolts (5) and the antenna drive (1).
(8) Install the bottom bolts (10) and the washers (9).
(9) TORQUE the bolts (5) and (10) to between 3.87 and 3.22 m.daN (28.54 and 23.75 lbf.ft )

.
(10) Make sure that the bonding contact resistance between the antenna drive (1) and the structure (7) is not higher than 5 milliohms (Ref. AMM TASK 20-28-00-912-802).
(11) Remove the blanking caps from the electrical connectors (11) and (12), and from the flange of the wave guide (4).
(12) Put a new AIPC 34-41-01-02-120 O-RING (3) (3) or a new AIPC 34-41-81-02-140 O-RING (3) (3) in the correct position on the flange of the wave guide (4).
(13) Connect the wave guide (4) to the antenna drive (1) with the quick-disconnect clamp (8).
(14) Connect the electrical connector(s) (11).

Subtask 34-41-11-420-057-B ** ON A/C NOT FOR ALL

D. Installation of the Weather Radar Antenna

NOTE: Two persons are necessary for the installation of the antenna. One person holds the antenna and the other person installs all the bolts.

NOTE: It is possible to install the antenna (17) with the antenna drive (1) installed on the aircraft.

(1) Put the dowels (13) in the holes (18) of the antenna (17).
(2) Engage the support (16) between the slots (15).
(3) TORQUE the bolts (14) to between 0.25 and 0.20 m.daN (22.12 and 17.70 lbf.in )

(4) Safety the bolts (14) with the 14QFC1Wire-Locking Dia: 0.8 mm CRES -.
(5) Make sure that the antenna (17) turns correctly in azimuth and in elevation.

Subtask 34-41-11-865-061-A ** ON A/C NOT FOR ALL

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

PANEL	DESIGNATION	FIN	LOCATION
** ON A/C NOT FOR ALL
121VU	COM NAV/RADAR/1	5SQ1	K13

Subtask 34-41-11-730-053-A ** ON A/C NOT FOR ALL

F. Do the system test of the weather radar (antenna control test) (Ref. AMM TASK 34-41-00-730-001).

5. Close-up
Subtask 34-41-11-410-053-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) Close radome 110AL (Ref. AMM TASK 53-15-11-410-001).
(3) Remove the access platform(s).
(4) Remove the WARNING NOTICE(S).

[Rev.10 from 2021] 2026.04.01 04:00:57 UTC