190-02081-03
GFC 600H HFCS Part 27 STC Maintenance Manual
Rev. 3
Page 7-9
7.7 Post-Installation Calibration
The following post-installation calibration procedures must be performed prior to operation of the
GFC 600H system after the mechanical and electrical installation of the GMC 605H, GSU 75H, and
GMU 44.
NOTE
Mounting rack(s) and support shelves must not be adjusted if GMC 605H, GSU 75H, or
GMU 44( ) unit is removed and replaced after it is calibrated; otherwise, a new
calibration must take place before the aircraft is returned to service if rack or its fasteners
are loosened.
NOTE
Repeat of the GMC 605H or GRS 79H or GSU 75H Pitch/Roll Offset Procedure requires a
repeat of the Magnetometer Calibration and Heading Offset Calibration.
NOTE
If any ferrous, magnetic, or electrical components are added, removed, or modified within
10 feet of the GMU 44( ) location after the Magnetometer Interference Test or
Magnetometer Calibration is completed, then both magnetometer interference and
calibration must be repeated before the aircraft can be returned to service.
Use Table 7-2 to determine whether calibration is required for the GMC 605H, GRS 79H or GSU 75H,
and/or GMU 44( ). Once all calibrations are complete, perform functional checkout and return-to-service
procedures in Section 1.