DOC AIRBUS | AMM A320FADIRU Removal Criteria
TASK 34-12-34-200-001-A
ADIRU Removal Criteria
To make sure that the performance parameters of the ADIRUs are satisfactory for operation in Class II navigation airspace in the range specified in the FAR drift rate requirement.
To do this, do a check of the ADIRUs for radial position errors.
This procedure gives accurate removal criteria.
2. Job Set-up Information
A. Work Zones and Access Panels
B. Referenced Information
3. Job Set-up
Subtask 34-12-34-860-052-A ** ON A/C NOT FOR ALL
Subtask 34-12-34-740-051-A
Subtask 34-12-34-860-053-A
[Rev.10 from 2021]
2026.04.02 06:23:06 UTC
ADIRU Removal Criteria
NOTE: The following procedure can ONLY be accomplished at the end of a flight: BEFORE the Air Data/Inertial Reference Units (ADIRU) are turned OFF AND before a new alignment has been started AND before starting to load the new flight plan into the Flight Management and Guidance Computer (FMGC).
ZONE: 210
1. Reason for the JobTo make sure that the performance parameters of the ADIRUs are satisfactory for operation in Class II navigation airspace in the range specified in the FAR drift rate requirement.
To do this, do a check of the ADIRUs for radial position errors.
This procedure gives accurate removal criteria.
2. Job Set-up Information
A. Work Zones and Access Panels
| ZONE/ACCESS | ZONE DESCRIPTION |
|---|---|
| 210 | CKPT,FWD COMPT BHD TO FLT COMPT BULKHEAD |
| REFERENCE | DESIGNATION |
|---|---|
| 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 31-60-00-860-001-A | EIS Start Procedure |
| TASK 31-60-00-860-002-A | EIS Stop Procedure |
| TASK 34-10-00-860-005-A | ADIRS Stop Procedure |
| TASK 34-12-34-000-001-A | Removal of the ADIRU |
| TASK 34-12-34-400-001-A | Installation of the ADIRU |
ADIRU - Radial Position Error - Removal CriteriaSubtask 34-12-34-860-052-A ** ON A/C NOT FOR ALL
A. Aircraft Maintenance Configuration
(1) Make sure that the electrical network is energized (Ref. AMM TASK 24-41-00-861-002).
(2) If necessary, do the EIS start procedure (Ref. AMM TASK 31-60-00-860-001).
(3) On the overhead panel:
Subtask 34-12-34-860-052-B ** ON A/C NOT FOR ALL (1) Make sure that the electrical network is energized (Ref. AMM TASK 24-41-00-861-002).
(2) If necessary, do the EIS start procedure (Ref. AMM TASK 31-60-00-860-001).
(3) On the overhead panel:
- On the ADIRS CDU, make sure that the three OFF/NAV/ATT selector switches are at NAV.
A. Aircraft Maintenance Configuration
(1) Make sure that the electrical network is energized (Ref. AMM TASK 24-41-00-861-002).
(2) If necessary, do the EIS start procedure (Ref. AMM TASK 31-60-00-860-001).
(3) On the overhead panel:
4. Procedure(1) Make sure that the electrical network is energized (Ref. AMM TASK 24-41-00-861-002).
(2) If necessary, do the EIS start procedure (Ref. AMM TASK 31-60-00-860-001).
(3) On the overhead panel:
- On ADIRS MSU panel 41VU, make sure that the three OFF/NAV/ATT selector switches are at NAV.
Subtask 34-12-34-740-051-A
A. Radial Position Error (RPE)
(1) Calculate the NAV time of the ADIRU as follows:
(a) If the RPE is below the grey band (refer to AREA 1):
5. Close-upNOTE: At the end of the flight, the pilot must make an entry of the RPE in the logbook.
NOTE: Do this procedure only at the end of a flight:
- before the ADIRUs are off and
- before you start a new alignment and
- before you load a new flight plan into the FMGC.
| ACTION | RESULT |
|---|---|
| On the center pedestal, on one MCDU: | On the MCDU: |
| 1.Push the line key adjacent to the FMGC indication | The FMGC page comes into view. |
| 2.On the keyboard, push the DATA mode key | The DATA INDEX page comes into view. |
| 3.Push the line key adjacent to the POSITION MONITOR indication | The POSITION MONITOR page comes into view. |
| 4.Record each IRS position error shown on line 5. | |
- record the flight time of the last ADIRU alignment and add 30 minutes to this time.
NOTE: This 30-minute period is the assumed time interval from the end point of the ADIRU alignment and aircraft door closing before pushback.
(2) Compare the recorded values with the curve at the time value calculated. (a) If the RPE is below the grey band (refer to AREA 1):
- the ADIRU is serviceable and no action is necessary.
- it is not necessary to replace the ADIRU but you must do a second check of the RPE immediately after the subsequent flight. If the RPE is again in the grey band, replace the ADIRU (Ref. AMM TASK 34-12-34-000-001) and (Ref. AMM TASK 34-12-34-400-001).
- replace the ADIRU (Ref. AMM TASK 34-12-34-000-001) and (Ref. AMM TASK 34-12-34-400-001).
Subtask 34-12-34-860-053-A
A. Aircraft Maintenance Configuration
(1) Do the ADIRS stop procedure (Ref. AMM TASK 34-10-00-860-005).
(2) Do the EIS stop procedure (Ref. AMM TASK 31-60-00-860-002).
(3) De-energize the aircraft electrical circuits
(Ref. AMM TASK 24-41-00-862-002).
(1) Do the ADIRS stop procedure (Ref. AMM TASK 34-10-00-860-005).
(2) Do the EIS stop procedure (Ref. AMM TASK 31-60-00-860-002).
(3) De-energize the aircraft electrical circuits
(Ref. AMM TASK 24-41-00-862-002).