Removal of the Weather-Radar Antenna Assembly

TASK 34-41-11-000-012-A
Removal of the Weather-Radar Antenna Assembly

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 THE WORK IN AN AREA THAT HAS PROTECTION FROM WEATHER. WIND CAN CAUSE SUDDEN UNWANTED MOVEMENT OF THE ANTENNA, WITH A RISK OF DAMAGE. RAIN CAN GO INTO THE RADOME AREA AND CAUSE INCORRECT WEATHER DATA ON THE ND.

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	SAFETY CLIP - CIRCUIT BREAKER
No specific	AR	WARNING NOTICE(S)

B. Work Zones and Access Panels

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

C. Referenced Information

REFERENCE	DESIGNATION
TASK 34-41-51-000-001-A	Removal of the Transmitter Receiver Unit
TASK 53-15-11-010-001-A	Opening of the Radome
Weather Radar Antenna
Weather Antenna Drive-Unit

3. Job Set-up
Subtask 34-41-11-865-082-A ** ON A/C NOT FOR ALL

A. Open, safety and tag this(these) circuit breaker(s):

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

Subtask 34-41-11-010-060-A ** ON A/C NOT FOR ALL

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

4. Procedure
Subtask 34-41-11-020-072-A ** ON A/C NOT FOR ALL

A. Removal of the Antenna Plate

NOTE: Two persons are necessary for this procedure. One person holds the antenna and the other person removes all the screws.

(1) Hold the antenna (1) and remove the four screws (5).
(2) Carefully pull the antenna (1) from the weather antenna drive (3) to disconnect the antenna waveguide (4) from the elevator mount waveguide (2).

NOTE: The two parts of the waveguide are fit into each other.

(3) Put the antenna (1) in a plastic bag and in a correct container.

Subtask 34-41-11-020-073-A ** ON A/C NOT FOR ALL

B. Removal of the Antenna Assembly

Weather Antenna Drive-Unit ** ON A/C NOT FOR ALL

(1) Remove the Transmitter Receiver Unit (TRU) 1 (7) (Ref. AMM TASK 34-41-51-000-001) and put it in a plastic bag.
(2) Remove the two lower bolts (9) and washers (8) from the base of the weather antenna drive-unit (3).
(3) Loosen the two upper bolts (5) and the washers (6) at the top. Do not remove them.
(4) Lift the weather antenna drive-unit (3) until the holes (4) are at the same level as the two top screws (5), then pull carefully.
(5) Remove the weather antenna drive-unit (3) and put it in a plastic bag and in a correct container.

[Rev.10 from 2021] 2026.04.01 01:01:05 UTC