Garmin G3X Pilot's Manual page 367

5) G3X: From the PFD or PFD Page, press the HDG/ROLL Softkey to access
the autopilot lateral modes and then press the AP NAV Softkey.
Or: Press or the NAV Key on the GMC 305
If there is less than half-scale deviation when the AP NAV Softkey or NAV
Key is pressed, VOR Mode will activate (green text), intercept, and track
the selected radial. If there is more than half-scale deviation when the AP
NAV Softkey or NAV Key is pressed, VOR Mode will arm (white text) first,
then activate when closer to the radial.
6) Adjust the aircraft's pitch axis as required.
LOCALIZER APPROACH (NO GS)
LOC Mode is used to fly a localizer only approach (no glideslope).
Selecting LOC Mode for a localizer only approach:
1) EXTERNAL NAVIGATOR: Tune and activate the desired LOC frequency,
2) G3X: Ensure that LOC1 is the selected navigation source (use the CDI
SRC Softkey on the PFD or PFD Page to cycle through external navigation
sources if necessary). The HSI should automatically slew the needle to the
correct course.
3) G3X: From the PFD, press the HDG/ROLL Softkey to access the autopilot
lateral modes and then press the AP NAV Softkey to activate LOC Mode.
Or: Press or the NAV Key on the GMC 305
If the localizer deviation is less than half-scale when the AP NAV Softkey
or NAV Key is pressed, the autopilot will activate LOC Mode and track the
localizer, otherwise LOC Mode is armed and the pilot is responsible for
intercepting the localizer. In some cases it may be necessary to use HDG
Mode with LOC Mode armed to follow a vector to the localizer.
190-01115-00 Rev. K Garmin G3X Pilot's Guide
AFCS
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