DOC AIRBUS | AMM A320FOperational Check and Detailed Inspection for Contamination of Radio Altimeter Fan
TASK 34-42-00-750-001-A
Operational Check and Detailed Inspection for Contamination of Radio Altimeter Fan
Refer to the MPD TASK: 344200-01
OPERATIONAL CHECK AND DETAILED INSPECTION FOR CONTAMINATION OF RADIO ALTIMETER FAN
2. Job Set-up Information
A. Fixtures, Tools, Test and Support Equipment
B. Work Zones and Access Panels
C. Referenced Information
3. Job Set-up
Subtask 34-42-00-860-056-A
Subtask 34-42-00-020-050-A Subtask 34-42-00-210-051-A
Subtask 34-42-00-410-050-A
[Rev.10 from 2021]
2026.04.02 07:15:10 UTC
Operational Check and Detailed Inspection for Contamination of Radio Altimeter Fan
WARNING:
MAKE SURE THAT ALL THE CIRCUITS IN MAINTENANCE ARE ISOLATED BEFORE YOU SUPPLY ELECTRICAL POWER TO THE AIRCRAFT. UNWANTED ELECTRICAL POWER CAN BE DANGEROUS.
ZONE: 152
1. Reason for the JobRefer to the MPD TASK: 344200-01
OPERATIONAL CHECK AND DETAILED INSPECTION FOR CONTAMINATION OF RADIO ALTIMETER FAN
2. Job Set-up Information
A. Fixtures, Tools, Test and Support Equipment
| REFERENCE | QTY | DESIGNATION |
|---|---|---|
| No specific | AR | ACCESS PLATFORM 2M (6 FT) |
| No specific | AR | BLOWING EQUIPMENT - DRY AIR |
| No specific | AR | BRUSH - BRISTLED, SOFT |
| ZONE/ACCESS | ZONE DESCRIPTION |
|---|---|
| 152 | AFT CARGO COMPARTMENT |
| 152GW, 826 |
| REFERENCE | DESIGNATION |
|---|---|
| TASK 22-97-00-710-001-A | Operational Test of the LAND CAT III Capability |
| 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) |
| TASK 34-42-00-740-002-A | BITE Test of the Radio Altimeter |
| TASK 34-42-33-000-001-A | Removal of the Radio Altimeter Transceiver |
| TASK 34-42-33-400-001-A | Installation of the Radio Altimeter Transceiver |
| TASK 34-42-45-000-001-A | Removal of the Radio Altimeter-Transceiver Fan |
| TASK 34-42-45-400-001-A | Installation of the Radio Altimeter-Transceiver Fan |
| TASK 52-30-00-860-001-A | Open the FWD or Aft Cargo-Compartment Door with the Yellow Electric Pump |
| TASK 52-30-00-860-002-A | Close the FWD or Aft Cargo-Compartment Door with the Yellow Electric Pump |
Subtask 34-42-00-860-056-A
A. Aircraft Maintenance Configuration
(1) Energize the aircraft electrical circuits
(Ref. AMM TASK 24-41-00-861-002).
Subtask 34-42-00-010-050-A (1) Energize the aircraft electrical circuits
(Ref. AMM TASK 24-41-00-861-002).
B. Get Access
(1) Put an ACCESS PLATFORM 2M (6 FT) in position at the aft cargo door 826.
(2) Open the aft cargo door 826 (Ref. AMM TASK 52-30-00-860-001).
(3) Remove the sidewall panel 152GW.
Subtask 34-42-00-865-055-A (1) Put an ACCESS PLATFORM 2M (6 FT) in position at the aft cargo door 826.
(2) Open the aft cargo door 826 (Ref. AMM TASK 52-30-00-860-001).
(3) Remove the sidewall panel 152GW.
C. Make sure that this(these) circuit breaker(s) is(are) open, safetied and tagged:
4. Procedure| 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 34-42-00-020-050-A Subtask 34-42-00-210-051-A
B. Detailed Inspection of the two RA transceiver Fans
(1) Do a detailed visual inspection of the two RA transceiver fans and of the fan housing.
(2) Remove the RA transceiver fans (Ref. AMM TASK 34-42-45-000-001).
(3) Lock the RA transceiver fans and their housings to prevent movement.
(5) Install the RA transceiver fans (Ref. AMM TASK 34-42-45-400-001).
Subtask 34-42-00-420-050-A (1) Do a detailed visual inspection of the two RA transceiver fans and of the fan housing.
(2) Remove the RA transceiver fans (Ref. AMM TASK 34-42-45-000-001).
(3) Lock the RA transceiver fans and their housings to prevent movement.
NOTE: When you clean the fan with the air blower, the fan can turn too quickly and thus a fault can occur.
(4) Clean the RA transceiver fans and their housings with a BRUSH - BRISTLED, SOFT and/or an BLOWING EQUIPMENT - DRY AIR. (5) Install the RA transceiver fans (Ref. AMM TASK 34-42-45-400-001).
C. Install the two Radio Altimeter Transceivers (Ref. AMM TASK 34-42-33-400-001).
(1) Close the circuit breakers 1SA1 and 1SA2 on the panel 121VU.
Subtask 34-42-00-720-053-A (1) Close the circuit breakers 1SA1 and 1SA2 on the panel 121VU.
D. Functional Test
Subtask 34-42-00-740-052-A | ACTION | RESULT |
|---|---|
| 1.On the rear circuit breaker panel 121VU: | In the aft cargo compartment (zone 152, door 826), below the transceiver mount: |
|
|
|
|
E. Do the BITE test of the radio altimeter (Ref. AMM TASK 34-42-00-740-002).
5. Close-upNOTE: If the airline operates the aircraft in CAT III conditions, you must also do the LAND CAT III capability test (Ref. AMM TASK 22-97-00-710-001).
Subtask 34-42-00-410-050-A
A. Close Access
(1) Install the sidewall panel 152GW.
(2) Close the aft cargo door 826 (Ref. AMM TASK 52-30-00-860-002).
(3) Remove the access platform(s).
Subtask 34-42-00-865-059-A (1) Install the sidewall panel 152GW.
(2) Close the aft cargo door 826 (Ref. AMM TASK 52-30-00-860-002).
(3) Remove the access platform(s).
B. Make sure that this(these) circuit breaker(s) is(are) closed:
Subtask 34-42-00-860-057-A | PANEL | DESIGNATION | FIN | LOCATION |
|---|---|---|---|
| ** ON A/C ALL | |||
| 121VU | COM NAV/RAD ALTM/2 | 1SA2 | K12 |
| 121VU | COM NAV/RAD ALTM/1 | 1SA1 | K11 |
C. Put the aircraft back to its initial configuration.
(1) De-energize the aircraft electrical circuits
(Ref. AMM TASK 24-41-00-862-002).
(2) Make sure that the work area is clean and clear of tools and other items.
(1) De-energize the aircraft electrical circuits
(Ref. AMM TASK 24-41-00-862-002).
(2) Make sure that the work area is clean and clear of tools and other items.