G900X/G950 Installation and Maintenance Manual – Software, Configuration, and Calibration
Page 15-41
190-00719-00
Revision D
15.4.3.4 Procedure B: GRS 77/GMU 44 Magnetic Calibration
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. The accuracy of the AHRS cannot be guaranteed if this calibration
is not performed on a magnetically clean compass rose. If the compass rose condition is not known, it is
recommended that the technician follow the guidance in Section 15.4.3.3.
1.
Start the aircraft engine.
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°).
CAUTION
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. THE ACCURACY OF THE AHRS CANNOT BE GUARANTEED
IF THIS CALIBRATION IS NOT PERFORMED ON A MAGNETICALLY CLEAN
COMPASS ROSE OR EQUIVALENT.
4.
Restart the PFD(s) and MFD in configuration mode.
5.
Go to the GRS Page Group on PFD #1.
Figure 15-29. GRS/GMU Calibration