Garmin G3X Touch Pilot's Manual page 369

5) EXTERNAL NAVIGATOR: Tune and identify the localizer frequency by
pressing the VLOC Flip-flop Key. (Note: The external navigator should have
automatically loaded the localizer frequency into the standby VLOC slot.)
6) G3X Touch: From the PFD touch the autopilot and touch APPR to arm LOC
and GS modes. Touch ALT.
Or:
APR Key on the GMC control unit.
Press the
GPS Mode is now active and LOC Mode is armed in the roll axis. ALT Mode
is active and GS is armed in the pitch axis. The flight director should now
navigate the entire approach from the IAF (Initial Approach Fix) to the MAP
(Missed Approach Point) with the only adjustment being the throttle.
NOTE: Check step #5 if the external navigator doesn't automatically switch
from GPS to VLOC Mode shortly after turning inbound on the final approach
course.
INTERCEPTING AND FLYING A DME ARC
The AFCS will intercept and track a DME arc that is part of the active flight plan
provided that GPS Navigation Mode is engaged, GPS is the active navigation source
on the CDI, and the DME arc segment is the active flight plan leg. It is important
to note that automatic navigation of DME arcs is based on GPS. Thus, even if the
APR key is pressed and LOC or VOR Approach Mode is armed prior to reaching the
Initial Approach Fix (IAF), Approach Mode will not activate until the arc segment is
completed.
If the pilot decides to intercept the arc at a location other than the published IAF (i.e.
ATC provides vectors to intercept the arc) and subsequently selects Heading Mode or
Roll Mode, the AFCS will not automatically intercept or track the arc unless the pilot
activates the arc leg of the flight plan and arms GPS Navigation Mode. The AFCS will
not intercept and fly a DME arc before reaching an IAF that defines the beginning of
the arc segment. Likewise, if at any point while established on the DME arc the pilot
deselects GPS Navigation Mode, the AFCS will no longer track the arc.
190-01754-00 Rev. L Garmin G3X Touch Pilot's Guide
AFCS
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