Garmin G1000 Nxi System Maintenance Manual page 325

Procedure B: GSU 75, GRS 77, or GRS 7800 and GMU 44 Magnetic
Calibration
Procedure A-1 (Section 7.10.1) must first be successfully accomplished before
performing Procedure B, only for situations where the GSU/GRS was replaced
with a new unit.
On the calibration pages, "GRS" refers to whatever GRS or GSU unit is
installed.
1. Start the aircraft engine following the procedures referenced in the appropriate King Air
AFM or AFMS as shown in the General Arrangement drawing, listed in Table 1-1.
2. After aircraft engine startup, taxi the aircraft to a properly calibrated compass rose.
3. At the compass rose, align the aircraft to a heading of magnetic north (±5°).
Calibration Procedure B must be carried out on a compass rose in order to
guarantee measurements free of environmental magnetic disturbances.
Attempting to carry out this maneuver on a typical ramp area may not yield a
successful calibration.
guaranteed if this calibration is not performed on a magnetically clean compass
rose or equivalent. If the compass rose condition is not known, it is
recommended that the technician follow the guidance in Section 7.10.2.
This procedure provides instructions for calibrating both GRS AHRS or both
GSU ADAHRS separately. It is acceptable to calibrate both GRS AHRS or
both GSU ADAHRS simultaneously by putting both PFD 1 and PFD 2 in
configuration mode and following the procedure below, using PFD 1 to
calibrate GSU/GRS 1 and PFD 2 to calibrate GSU/GRS 2.
4. Restart PFD 1 in configuration mode.
5. Go to the GRS Page Group on the PFD.
6. Select the GRS/GMU Calibration page and enter the following softkey password:
•
9
•
10
•
11
•
12 (far right softkey)
7. Use the FMS small knob to highlight GRS/GSU for calibration and press the ENT key.
8. Using the FMS small knob, select MAGNETOMETER. Press the ENT button.
9. Use the cursor to highlight the first step in the BEFORE CALIBRATION window.
10. Follow the checklist items displayed on the PFD and press the ENT key as each one is
completed or confirmed. When the CALIBRATE field is blinking, press the ENT key to
begin the procedure.
G1000 NXi System Maintenance Manual
King Air 300 Series
190-00716-N1
NOTES
CAUTION
The accuracy of the AHRS/ADAHRS cannot be
NOTE
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