Cleaning of the Radio Altimeter Antenna External Surface

TASK 34-42-11-615-001-A
Cleaning of the Radio Altimeter Antenna External Surface

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

ZONE: 150
FIN: 5SA1
FIN: 5SA2
FIN: 6SA1
FIN: 6SA2

1. Reason for the Job
Refer to the MPD TASK: 344200-03
CLEANING OF RADIO ALTIMETER ANTENNA EXTERNAL SURFACE.

The cleaning of the Radio Altimeter (RA) antennas is necessary because dirt can make them more sensitive to rain or to water from drain holes.
2. Job Set-up Information
A. Fixtures, Tools, Test and Support Equipment

REFERENCE	QTY	DESIGNATION
No specific	AR	SAFETY CLIP - CIRCUIT BREAKER

B. Consumable Materials

REFERENCE	DESIGNATION
FOR [5SA1] (ANTENNA-RA RCPTN, 1)
FOR [5SA2] (ANTENNA-RA RCPTN, 2)
FOR [6SA1] (ANTENNA-RA XMSN, 1)
FOR [6SA2] (ANTENNA-RA XMSN, 2)
(Material No.08BBD1)	Non Aqueous Cleaner-- Isopropyl Alcohol -
(Material No.14SBA1)	Textile-Lint free Cotton -

C. Work Zones and Access Panels

ZONE/ACCESS	ZONE DESCRIPTION
150	AFT CARGO COMPARTMENT FWD PRESS BULKHEAD TO AFT BULKHEAD OF AFT CARGO COMPARTMENT

D. Referenced Information

REFERENCE	DESIGNATION
External Surface of the Radio Altimeter Antennas 5SA1, 5SA2, 6SA1 and 6SA2

3. Job Set-up
Subtask 34-42-11-865-062-A

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

PANEL	DESIGNATION	FIN	LOCATION
** ON A/C ALL
121VU	COM NAV/RAD ALTM/2	1SA2	K12
121VU	COM NAV/RAD ALTM/1	1SA1	K11

4. Procedure
Subtask 34-42-11-615-050-A

A. Cleaning of the External Surface of the Radio Altimeter Antennas 5SA1, 5SA2, 6SA1 and 6SA2

External Surface of the Radio Altimeter Antennas 5SA1, 5SA2, 6SA1 and 6SA2

(1) FOR [5SA1] (ANTENNA-RA RCPTN, 1), [5SA2] (ANTENNA-RA RCPTN, 2), [6SA1] (ANTENNA-RA XMSN, 1), [6SA2] (ANTENNA-RA XMSN, 2)
(a) Clean the radio altimeter antennas with the Non Aqueous Cleaner-- Isopropyl Alcohol - (Material No.08BBD1) and a Textile-Lint free Cotton - (Material No.14SBA1) .

NOTE: Because of the MPD task interval, there is a risk that part of the paint from the red markings ("DO NOT PAINT" and "FWD") can get erased. But this has no unwanted effect on the correct operation of the radio altimeter system.

(b) Clean the fuselage area around the radio altimeter antennas with the Non Aqueous Cleaner-- Isopropyl Alcohol - (Material No.08BBD1) and a Textile-Lint free Cotton - (Material No.14SBA1) .

NOTE: The cleaning of the fuselage area around the RA antennas is necessary to make sure that dirt does not move to the antennas.

5. Close-up
Subtask 34-42-11-865-063-A

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

PANEL	DESIGNATION	FIN	LOCATION
** ON A/C ALL
121VU	COM NAV/RAD ALTM/2	1SA2	K12
121VU	COM NAV/RAD ALTM/1	1SA1	K11

Subtask 34-42-11-942-052-A

B. Aircraft Maintenance Configuration
(1) Make sure that the work area is clean and clear of tools and other items.
(2) Remove the ground support and maintenance equipment, the special and standard tools and all other items.

[Rev.10 from 2021] 2026.04.02 06:23:24 UTC