Loss of RA Display on Ground on CAPT and F/O PFDs

TASK 34-42-00-810-847-A
Loss of RA Display on Ground on CAPT and F/O PFDs

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

1. Possible Causes

ANTENNA-RA RCPTN, 1 [5SA1]
ANTENNA-RA XMSN, 1 [6SA1]
ANTENNA-RA RCPTN, 2 [5SA2]
ANTENNA-RA XMSN, 2 [6SA2]
coaxial cables

2. Job Set-up Information
A. Consumable Materials

REFERENCE	DESIGNATION
(Material No.08BBD1)	Non Aqueous Cleaner-- Isopropyl Alcohol -
(Material No.14SBA1)	Textile-Lint free Cotton -

B. Referenced Information

REFERENCE	DESIGNATION
ESPM 2053230
ASM 344201
ASM 344202
AMM 34-42-11-000-001	Removal of the Radio Altimeter Antenna
AMM 34-42-11-400-001	Installation of the Radio Altimeter Antenna
AMM 34-42-11-615-001	Cleaning of the External Surface of the Radio Altimeter Antennas

3. Fault Confirmation
Subtask 34-42-00-740-119-A

A. Not applicable, the fault is evident.

4. Fault Isolation
Subtask 34-42-00-810-106-A

A. If there is confirmation of the fault:

Make sure that there are no objects (such as towbar) in the area near the Radio Altimeter (RA) antennas.
Make sure the area below the Radio Altimeter (RA) antennas is not contaminated with fluids (such as water, oil...) or rough substance (snow, grass...).
Clean the external surface of the RA antennas with Non Aqueous Cleaner-- Isopropyl Alcohol - (Material No.08BBD1) and Textile-Lint free Cotton - (Material No.14SBA1) AMM 34-42-11-615-001.

(1) If the fault continues:
(a) Remove the ANTENNA-RA RCPTN, 1 [5SA1] and the ANTENNA-RA XMSN, 1 [6SA1] AMM 34-42-11-000-001.
(b) Remove the ANTENNA-RA RCPTN, 2 [5SA2] and the ANTENNA-RA XMSN, 2 [6SA2] AMM 34-42-11-000-001.
(c) Make sure that the coaxial cables between the RA transceivers 1 and 2 pins AA/C and AB/C and the radio altimeter antennas are in correct condition (no corrosion) ASM 344201 and ASM 344202.
1 If the antenna coaxial cables are not in correct condition:

Repair or replace if necessary, the defective coaxial cables ESPM 2053230.
Install the new RA reception antenna 1 (5SA1), the new RA transmission antenna 1 (6SA1), the new RA reception antenna 2 (5SA2) and the new RA transmission antenna 2 (6SA2) AMM 34-42-11-000-001 and AMM 34-42-11-400-001.

2 If the antenna coaxial cables are in correct condition:

Install the new RA reception antenna 1 (5SA1), the new RA transmission antenna 1 (6SA1), the new RA reception antenna 2 (5SA2) and the new RA transmission antenna 2 (6SA2) AMM 34-42-11-000-001 and AMM 34-42-11-400-001.

Subtask 34-42-00-740-120-A

B. Do the test given in Para. 3.

[Rev.8 from Aug 2018] 2026.04.04 04:33:11 UTC