W DOC AIRBUS | AMM A320F

Compensation Adjustment/Test of the Standby Compass with the Standby Compass Calibrator

TASK 34-22-00-730-001-A-02
Compensation Adjustment/Test of the Standby Compass with the Standby Compass Calibrator

NOTE: To move the aircraft for this procedure, you can use:
  • A tractor (before each adjustment, it is necessary to disconnect the tractor and the towbar and move the tractor minimum 70 meters (230 ft.) away from the aircraft), or
  • The aircraft engines (this is the recommended procedure).
ZONE: 210
FIN: 2FN
1. Reason for the Job
  • To adjust the compensation of the standby compass
  • To find the deviation curve of the compass values when they are more than + or - 2°.
2. Job Set-up Information
 A. Fixtures, Tools, Test and Support Equipment
REFERENCE
QTY
DESIGNATION
2591553-901
1
CALIBRATOR,STANDBY COMPASS
OR
OR
2591553-903
1
STANBY COMPASS CALIB
CE2-40
1
KEY-CORRECTOR
 B. Work Zones and Access Panels
ZONE/ACCESS
ZONE DESCRIPTION
210
CKPT,FWD COMPT BHD TO FLT COMPT BULKHEAD
 C. Expendable Parts
FIG.ITEM
DESIGNATION
IPC-CSN
1
TWO CORRECTION CARDS
AIPC 11-31-34-01-010
1
TWO CORRECTION CARDS
AIPC 25-13-81-43-010
 D. Referenced Information
REFERENCE
DESIGNATION
TASK 31-60-00-860-001-A
EIS Start Procedure
TASK 31-60-00-860-002-A
EIS Stop Procedure
TASK 34-10-00-860-004-A
Inertial Reference (IR) Alignment-Procedure
TASK 34-10-00-860-004-A-01
Automatic Inertial Reference (IR) Alignment-Procedure
TASK 34-10-00-860-004-A-02
Inertial Reference (IR) Alignment-Procedure to do a Check of the Links between each Flight Management and Guidance Computer (FMGC) and the three Air Data/Inertial Reference Units (ADIRUs)
TASK 34-10-00-860-005-A
ADIRS Stop Procedure
TASK 34-22-00-710-001-A
Operational Check of the Standby Compass Including Light Test and Visual Check
TASK 34-22-00-710-001-A-01
Operational Check of the Standby Compass Including Light Test and Visual Check (with the Standby Compass Calibrator)
TASK 34-22-23-400-001-A
Installation of the Standby Compass
TASK 71-00-00-710-003-A
Engine Automatic Start
TASK 71-00-00-710-003-B
Engine Automatic Start
TASK 71-00-00-710-018-A
Discontinued Start, Restart and Shutdown Procedures
TASK 71-00-00-710-028-A
Engine Shutdown
TASK 71-00-00-710-028-B
Engine Shutdown
TASK 71-00-00-710-043-A
Normal Engine Automatic-Start Procedure
TASK 71-00-00-860-814-A
Shutdown of the Engine
TASK 71-00-00-860-823-A
Start the Engine (Normal Automatic Start)
F Standby Compass
F Standby Compass Calibration
3. Job Set-up
Subtask 34-22-00-860-069-B ** ON A/C NOT FOR ALL
CAUTION: MAKE SURE THAT THE AIRCRAFT IS IN THE SPECIFIED COMPENSATION AREA, AND THAT IT POINTS TO THE NORTH. YOU MUST CALIBRATE THE STANDBY COMPASS CALIBRATOR BEFORE YOU USE IT:
  • ONE TIME A YEAR IF THE COMPENSATION AREA REMAINS THE SAME.
  • EACH TIME THE COMPENSATION AREA CHANGES.
CAUTION: MAKE SURE THAT THERE IS NO RESIDUAL MAGNETISM ON THE CALIBRATOR (REFER TO THE STANDBY COMPASS COMPENSATOR SET OPERATION AND MAINTENANCE MANUAL). RESIDUAL MAGNETISM CAN CAUSE AN ERROR (DEFLECTION) IN ALL HEADINGS.
A. Aircraft Maintenance Configuration
NOTE: For this procedure, the aircraft must be on a compensation base that can support its weight. The compensation base must agree with the compensation procedure of Firstmark Operation and Maintenance Manual (Ref. EB2992052).
NOTE: It is necessary to do a check of the compensation area at every 12-months interval.
   (1) Make sure that there are no ferromagnetic parts installed near the standby compass.
NOTE: The ferromagnetic parts (fasteners, tools, etc.) near the standby compass can cause compass heading errors.
   (2) Start the engines (recommended procedure) (Ref. AMM TASK 71-00-00-710-043).
NOTE: You can also do the compensation procedure with the engines off.
   (3) Make sure that the standby compass operates correctly (Ref. AMM TASK 34-22-00-710-001).
   (4) Do the Electronic Instrument System (EIS) start procedure (Ref. AMM TASK 31-60-00-860-001).
   (5) On the Radio Management Panels (RMP), make sure that the ON/OFF selector switch is set to the ON position.
   (6) Do the Inertial Reference (IR) alignment procedure (Ref. AMM TASK 34-10-00-860-004).
   (7) Adjust the position of the aircraft:
  • The aircraft must point to the Magnetic Heading North (0 degree) given by the Air Data and Inertial Reference Unit (ADIRU) and shown on the ND with an accuracy of + or - 1°.
Subtask 34-22-00-860-069-D ** ON A/C NOT FOR ALL
CAUTION: MAKE SURE THAT THE AIRCRAFT IS IN THE SPECIFIED COMPENSATION AREA, AND THAT IT POINTS TO THE NORTH. YOU MUST CALIBRATE THE STANDBY COMPASS CALIBRATOR BEFORE YOU USE IT:
  • ONE TIME A YEAR IF THE COMPENSATION AREA REMAINS THE SAME.
  • EACH TIME THE COMPENSATION AREA CHANGES.
CAUTION: MAKE SURE THAT THERE IS NO RESIDUAL MAGNETISM ON THE CALIBRATOR (REFER TO THE STANDBY COMPASS COMPENSATOR SET OPERATION AND MAINTENANCE MANUAL). RESIDUAL MAGNETISM CAN CAUSE AN ERROR (DEFLECTION) IN ALL HEADINGS.
A. Aircraft Maintenance Configuration
NOTE: For this procedure, the aircraft must be on a compensation base that can support its weight. The compensation base must agree with the compensation procedure of Firstmark Operation and Maintenance Manual (Ref. EB2992052).
NOTE: It is necessary to do a check of the compensation area at every 12-months interval.
   (1) Make sure that there are no ferromagnetic parts installed near the standby compass.
NOTE: The ferromagnetic parts (fasteners, tools, etc.) near the standby compass can cause compass heading errors.
   (2) Start the engines (recommended procedure) (Ref. AMM TASK 71-00-00-710-003).
NOTE: You can also do the compensation procedure with the engines off.
   (3) Make sure that the standby compass operates correctly (Ref. AMM TASK 34-22-00-710-001).
   (4) Do the Electronic Instrument System (EIS) start procedure (Ref. AMM TASK 31-60-00-860-001).
   (5) On the Radio Management Panels (RMP), make sure that the ON/OFF selector switch is set to the ON position.
   (6) Do the Inertial Reference (IR) alignment procedure (Ref. AMM TASK 34-10-00-860-004).
   (7) Adjust the position of the aircraft:
  • The aircraft must point to the Magnetic Heading North (0 degree) given by the Air Data and Inertial Reference Unit (ADIRU) and shown on the ND with an accuracy of + or - 1°.
   (8) On the overhead panel, on the Air Data and Inertial Reference System (ADIRS) Control Display Unit (CDU), set the DISPLAY DATA selector switch to the HDG position.
Subtask 34-22-00-860-069-F ** ON A/C NOT FOR ALL
CAUTION: MAKE SURE THAT THE AIRCRAFT IS IN THE SPECIFIED COMPENSATION AREA, AND THAT IT POINTS TO THE NORTH. YOU MUST CALIBRATE THE STANDBY COMPASS CALIBRATOR BEFORE YOU USE IT:
  • ONE TIME A YEAR IF THE COMPENSATION AREA REMAINS THE SAME.
  • EACH TIME THE COMPENSATION AREA CHANGES.
CAUTION: MAKE SURE THAT THERE IS NO RESIDUAL MAGNETISM ON THE CALIBRATOR (REFER TO THE STANDBY COMPASS COMPENSATOR SET OPERATION AND MAINTENANCE MANUAL). RESIDUAL MAGNETISM CAN CAUSE AN ERROR (DEFLECTION) IN ALL HEADINGS.
A. Aircraft Maintenance Configuration
NOTE: For this procedure, the aircraft must be on a compensation base that can support its weight. The compensation base must agree with the compensation procedure of Firstmark Operation and Maintenance Manual (Ref. EB2992052).
NOTE: It is necessary to do a check of the compensation area at every 12-months interval.
   (1) Make sure that there are no ferromagnetic parts installed near the standby compass.
NOTE: The ferromagnetic parts (fasteners, tools, etc.) near the standby compass can cause compass heading errors.
   (2) Start the engines (recommended procedure) (Ref. AMM TASK 71-00-00-710-003).
NOTE: You can also do the compensation procedure with the engines off.
   (3) Make sure that the standby compass operates correctly (Ref. AMM TASK 34-22-00-710-001).
   (4) Do the Electronic Instrument System (EIS) start procedure (Ref. AMM TASK 31-60-00-860-001).
   (5) On the Radio Management Panels (RMP), make sure that the ON/OFF selector switch is set to the ON position.
   (6) Do the Inertial Reference (IR) alignment procedure (Ref. AMM TASK 34-10-00-860-004).
   (7) Adjust the position of the aircraft:
  • The aircraft must point to the Magnetic Heading North (0 degree) given by the Air Data and Inertial Reference Unit (ADIRU) and shown on the ND with an accuracy of + or - 1°.
Subtask 34-22-00-860-069-G ** ON A/C NOT FOR ALL
CAUTION: MAKE SURE THAT THE AIRCRAFT IS IN THE SPECIFIED COMPENSATION AREA, AND THAT IT POINTS TO THE NORTH. YOU MUST CALIBRATE THE STANDBY COMPASS CALIBRATOR BEFORE YOU USE IT:
  • ONE TIME A YEAR IF THE COMPENSATION AREA REMAINS THE SAME.
  • EACH TIME THE COMPENSATION AREA CHANGES.
CAUTION: MAKE SURE THAT THERE IS NO RESIDUAL MAGNETISM ON THE CALIBRATOR (REFER TO THE STANDBY COMPASS COMPENSATOR SET OPERATION AND MAINTENANCE MANUAL). RESIDUAL MAGNETISM CAN CAUSE AN ERROR (DEFLECTION) IN ALL HEADINGS.
A. Aircraft Maintenance Configuration
NOTE: For this procedure, the aircraft must be on a compensation base that can support its weight. The compensation base must agree with the compensation procedure of Firstmark Operation and Maintenance Manual (Ref. EB2992052).
NOTE: It is necessary to do a check of the compensation area at every 12-months interval.
   (1) Make sure that there are no ferromagnetic parts installed near the standby compass.
NOTE: The ferromagnetic parts (fasteners, tools, etc.) near the standby compass can cause compass heading errors.
   (2) Start the engines (recommended procedure) (Ref. AMM TASK 71-00-00-860-823).
NOTE: You can also do the compensation procedure with the engines off.
   (3) Make sure that the standby compass operates correctly (Ref. AMM TASK 34-22-00-710-001).
   (4) Do the Electronic Instrument System (EIS) start procedure (Ref. AMM TASK 31-60-00-860-001).
   (5) On the Radio Management Panels (RMP), make sure that the ON/OFF selector switch is set to the ON position.
   (6) Do the Inertial Reference (IR) alignment procedure (Ref. AMM TASK 34-10-00-860-004).
   (7) Adjust the position of the aircraft:
  • The aircraft must point to the Magnetic Heading North (0 degree) given by the Air Data and Inertial Reference Unit (ADIRU) and shown on the ND with an accuracy of + or - 1°.
Subtask 34-22-00-865-057-A
B. Make sure that these circuit breakers are closed to get the radio/ magnetic environment that usually occurs in flight :
PANELDESIGNATIONFINLOCATION
** ON A/C NOT FOR ALL
49VUNAV/ADF/11RP1H14
** ON A/C ALL
49VUNAV/VOR/12RS1G13
49VUCOM/VHF/12RC1G09
** ON A/C NOT FOR ALL
49VUHF11RE1HA14
** ON A/C NOT FOR ALL
49VUNAV PROBES/ADF/11RP1F09
** ON A/C NOT FOR ALL
121VUCOM NAV/VHF/32RC3L05
121VUCOM NAV/VHF/22RC2L04
** ON A/C ALL
121VUCOM NAV/VOR/22RS2K08
** ON A/C NOT FOR ALL
121VUCOM NAV/ADF/21RP2K02
** ON A/C NOT FOR ALL
121VUCOM/VHF/32RC3L05
121VUCOM/VHF/22RC2L04
** ON A/C NOT FOR ALL
121VUCOM NAV/HF21RE2L13
4. Procedure
Subtask 34-22-00-730-061-A
A. Installation of the Standby Compass Calibrator
F Standby Compass
F Standby Compass Calibration
   (1) Use the SCREWDRIVER WIDTH 2 MM (0,23 IN) - NON MAGNETIC to remove the four screws (1) from the plate (2) under the standby compass (4).
   (2) Remove the plate (2).
   (3) Use the SCREWDRIVER WIDTH 2 MM (0,23 IN) - NON MAGNETIC to remove the two screws (3) from the standby compass (4).
   (4) Install the 2591553-903 STANBY COMPASS CALIB2591553-901 CALIBRATOR,STANDBY COMPASS (5) with the two non-magnetic screws (6) and the two adjusting shims (7) on the standby compass (4).
Subtask 34-22-00-730-068-B
B. Compensation Adjustment/Test of the Standby Compass
NOTE: The reference magnetic heading is the magnetic heading indication read on the knob assembly of the standby compass compensator.
   (1) North (N) position compensation
     (a) On the standby compass compensator, set the two drums of the knob assembly to the N position.
     (b) On the standby compass, after the compass becomes stable:
  • Put the CE2-40 KEY-CORRECTOR (non-magnetic compensation key) into the C hole.
  • Adjust the N indication to make it agree with the heading indication of the standby compass compensator.
   (2) South (S) position compensation
     (a) On the standby compass compensator, set the two drums of the knob assembly to the S position.
     (b) On the standby compass, after the compass becomes stable:
  • Put the CE2-40 KEY-CORRECTOR (non-magnetic compensation key) into the C hole.
  • Adjust the S indication with the corrective value. The corrective value is equal to half the difference between the compass heading indication and the compass compensator.
    Example:
    If the standby compass compensator shows 180° (S), and the standby-compass heading indication shows 176° (180° - 176° = 4°) the corrective value is equal to half the difference (+2°).
   (3) East (E) position compensation
     (a) On the standby compass compensator, set the two drums of the knob assembly to the E position.
     (b) On the standby compass, after the compass becomes stable:
  • Put the CE2-40 KEY-CORRECTOR (non-magnetic compensation key) into the B hole.
  • Adjust the E indication to make it agree with the heading indication of the standby compass compensator.
   (4) West (W) position compensation
     (a) On the standby compass compensator, set the two drums of the knob assembly to the W position.
     (b) On the standby compass, after the compass becomes stable:
  • Put the CE2-40 KEY-CORRECTOR (non-magnetic compensation key) into the B hole.
  • Adjust the W indication by the corrective value. The corrective value is equal to half the difference between the compass heading indications and the compass compensator.
    Example:
    If the standby compass compensator shows 270° (W), and the standby-compass heading indication shows 274° (270° - 274° = -4°), the corrective value is equal to half the difference (-2°).
Subtask 34-22-00-730-069-A
C. Calculate the Deviation Curve
NOTE: During the adjustment procedure, the standby compass turns 360°. It is necessary to make sure that the letters and graduations on the compass are not damaged.
   (1) On the standby compass compensator, set the two drums of the knob assembly to the 12 headings one after the other to find the deviation curve:
0°, 30°, 60°, 90°, 120°, 150°, 180°, 210°, 240°, 270°, 300°, 330°
   (2) For each heading, write the magnetic heading values of the standby compass and the standby compass compensator.
  • Calculate the remaining deviation values R(°):
    R(°) = Magnetic Heading - indication of standby compass.
    For example, refer to the table that follows:
    -----------------------------------------------
    ! Reference ! Compass Indication ! R !
    ! Magnetic ! (example values) !(example !
    ! Heading ! ! values) !
    -----------------------------------------------
    ! 0° ! 2° ! -2° !
    ! 30° ! 28° ! 2° !
    ! 60° ! 62° ! -2° !
    ! 90° ! 88° ! 2° !
    ! 120° ! 119° ! 1° !
    ! 150° ! 151° ! -1° !
    ! 180° ! 179° ! 1° !
    ! 210° ! 212° ! -2° !
    ! 240° ! 241° ! -1° !
    ! 270° ! 272° ! -2° !
    ! 300° ! 298° ! 2° !
    ! 330° ! 332° ! -2° !
    -----------------------------------------------

     (a) Make sure that the remaining deviation values R are not more than 2° for each magnetic heading:
  • If the difference is more than 2°, do the compensation
  • If the difference stays more than 2°, do the compensation again
  • If the difference stays more than 2° after the compensation, make sure that the standby compass is correctly installed (Ref. AMM TASK 34-22-23-400-001) and do the compensation again.
   (3) On the AIPC 11-31-34-01-010 TWO CORRECTION CARDS (1) or AIPC 25-13-81-43-010 TWO CORRECTION CARDS (1), in the "To steer" empty field, write To fly(°) - R(°) (Remaining deviation values). Put the cards on each side of the support of the standby compass.
5. Close-up
Subtask 34-22-00-860-071-A ** ON A/C NOT FOR ALL
A. Put the aircraft back to its initial configuration.
   (1) Do the EIS stop procedure
(Ref. AMM TASK 31-60-00-860-002).
   (2) Do the ADIRS stop procedure (Ref. AMM TASK 34-10-00-860-005).
   (3) Remove the standby compass calibrator:
F Standby Compass ** ON A/C NOT FOR ALL
F Standby Compass Calibration ** ON A/C NOT FOR ALL
CAUTION: MAKE SURE THAT THE TWO DRUMS OF THE KNOB ASSEMBLY ARE ON THE "N" (NORTH) POSITION BEFORE YOU PUT THE STANDBY COMPASS COMPENSATOR INTO STORAGE. THIS WILL PREVENT DEMAGNETIZATION.
     (a) Remove the two non-magnetic screws (6), the two adjusting shims (7) and the 2591553-903 STANBY COMPASS CALIB2591553-901 CALIBRATOR,STANDBY COMPASS (5) from the standby compass (4).
     (b) Use the SCREWDRIVER WIDTH 2 MM (0,23 IN) - NON MAGNETIC to install the two screws (3) on the standby compass (4).
       1 Tighten the two screws (3).
     (c) Use the SCREWDRIVER WIDTH 2 MM (0,23 IN) - NON MAGNETIC to install the plate (2) with the four screws (1) under the standby compass (4).
       1 Tighten the four screws (1).
   (4) If necessary, stop the engines (Ref. AMM TASK 71-00-00-710-018).
   (5) Put the aircraft back to the serviceable condition.
   (6) Remove the ground support and maintenance equipment, the special and standard tools and all other items.
Subtask 34-22-00-860-071-C ** ON A/C NOT FOR ALL
A. Put the aircraft back to its initial configuration.
   (1) Do the EIS stop procedure
(Ref. AMM TASK 31-60-00-860-002).
   (2) Do the ADIRS stop procedure (Ref. AMM TASK 34-10-00-860-005).
   (3) Remove the standby compass calibrator:
F Standby Compass ** ON A/C NOT FOR ALL
F Standby Compass Calibration ** ON A/C NOT FOR ALL
CAUTION: MAKE SURE THAT THE TWO DRUMS OF THE KNOB ASSEMBLY ARE ON THE "N" (NORTH) POSITION BEFORE YOU PUT THE STANDBY COMPASS COMPENSATOR INTO STORAGE. THIS WILL PREVENT DEMAGNETIZATION.
     (a) Remove the two non-magnetic screws (6), the two adjusting shims (7) and the 2591553-903 STANBY COMPASS CALIB2591553-901 CALIBRATOR,STANDBY COMPASS (5) from the standby compass (4).
     (b) Use the SCREWDRIVER WIDTH 2 MM (0,23 IN) - NON MAGNETIC to install the two screws (3) on the standby compass (4).
       1 Tighten the two screws (3).
     (c) Use the SCREWDRIVER WIDTH 2 MM (0,23 IN) - NON MAGNETIC to install the plate (2) with the four screws (1) under the standby compass (4).
       1 Tighten the four screws (1).
   (4) If necessary, stop the engines (Ref. AMM TASK 71-00-00-710-028).
   (5) Put the aircraft back to the serviceable condition.
   (6) Remove the ground support and maintenance equipment, the special and standard tools and all other items.
Subtask 34-22-00-860-071-D ** ON A/C NOT FOR ALL
A. Put the aircraft back to its initial configuration.
   (1) Do the EIS stop procedure
(Ref. AMM TASK 31-60-00-860-002).
   (2) Do the ADIRS stop procedure (Ref. AMM TASK 34-10-00-860-005).
   (3) Remove the standby compass calibrator:
F Standby Compass ** ON A/C NOT FOR ALL
F Standby Compass Calibration ** ON A/C NOT FOR ALL
CAUTION: MAKE SURE THAT THE TWO DRUMS OF THE KNOB ASSEMBLY ARE ON THE "N" (NORTH) POSITION BEFORE YOU PUT THE STANDBY COMPASS COMPENSATOR INTO STORAGE. THIS WILL PREVENT DEMAGNETIZATION.
     (a) Remove the two non-magnetic screws (6), the two adjusting shims (7) and the 2591553-903 STANBY COMPASS CALIB2591553-901 CALIBRATOR,STANDBY COMPASS (5) from the standby compass (4).
     (b) Use the SCREWDRIVER WIDTH 2 MM (0,23 IN) - NON MAGNETIC to install the two screws (3) on the standby compass (4).
       1 Tighten the two screws (3).
     (c) Use the SCREWDRIVER WIDTH 2 MM (0,23 IN) - NON MAGNETIC to install the plate (2) with the four screws (1) under the standby compass (4).
       1 Tighten the four screws (1).
   (4) If necessary, stop the engines (Ref. AMM TASK 71-00-00-860-814).
   (5) Put the aircraft back to the serviceable condition.
   (6) Remove the ground support and maintenance equipment, the special and standard tools and all other items.
Subtask 34-22-00-080-052-A
B. Tool Storage:
At the end of the test, refer to the manufacturer recommendations.
[Rev.10 from 2021] 2026.04.01 00:59:49 UTC
"Aviabrain" 2025