Garmin GRS 77 Installation Manual page 40

Table 5-1. Post-Installation Calibration Procedure Summary
Calibration Procedure Name
Procedure
A-1 Pitch/Roll Offset
Compensation
A-2 Zero Pitch/Roll
Offsets by Manual
Entry
B Magnetometer
Calibration
C Heading Offset
Compensation
D Engine Run-Up
Vibration Test
E Magnetometer
Interference Test
If removal and replacement of a GRS 77 or GMU 44 unit is required after post-installation calibration has
been completed, the unit mounting racks must not be moved. If the mounting bolts that secure the
Page 5-2
Revision L
Procedure
Description
Level Aircraft Either procedure A-1 or A-2 is
required for all installations.
Procedure A-1 is recommended.
Manually enter This procedure should be used
zeros for pitch/roll only if leveling the aircraft is not
offsets (pass- feasible and the AHRS is mounted
code required) to within 0.25° of aircraft level
reference
Compass Rose All installations
Taxi Maneuver
Compass Rose Installations in which GMU 44
Alignment with alignment is not within 0.5° of
Magnetic North aircraft longitudinal axis
Validate vibration All installations
characteristics of
installation
Validate no Required for initial installation
magnetic certification.
interference with
GMU 44 This test should also be repeated to
verify all subsequent electrical
changes associated with devices
within 10.0 feet of the GMU 44
magnetometer. Such changes
include, but are not limited to, wiring,
shielding or grounding changes to
any light, strobe, beacon or other
electrical device located in the same
wing as a GMU 44 unit. Likewise,
this test should also be repeated to
verify all subsequent changes to
materials within 10.0 feet of the
GMU 44. Such changes include, but
are not limited to, addition, removal
or modification of ferrous or
electrically conductive materials
located in the same wing as a GMU
44 unit.
Garmin recommends this test be
performed at least once every 12
months by all aircraft
manufacturers on a minimum of
one production aircraft for every
airframe type or model equipped
with the G1000 system.
Installations Requiring
Procedure
GRS 77/GMU 44 Installation Manual
190-00303-10