Altitude Hold Mode (Alt) - Garmin G3X Pilot's Manual

Automatic transition to ALTS
Mode with ALT Mode armed
Setting the selected altitude (Integrated Autopilot Interface):
1) From the PFD Page (one display) or PFD (two display), press the ALT/PTCH
Softkey.
2) Turn the FMS Joystick to set the Selected Altitude in 100-ft increments
Setting the selected altitude (GMC 305):
1) From the PFD Page (one display) or PFD (two display), press the ALT
Softkey.
2) Turn the FMS Joystick to set the Selected Altitude in 100-ft increments
Use of the FMS Joystick to change the Selected Altitude while Selected
Altitude Capture Mode is active causes the autopilot to revert to Pitch Hold
Mode with Selected Altitude Capture Mode armed for the new Selected
Altitude.

ALTITUDE HOLD MODE (ALT)

Altitude Hold Mode can be activated by pressing the AP ALT Softkey or
ALT Key (GMC 305); the AFCS maintains the current aircraft altitude (to the
nearest 10 feet) as the Altitude Reference. The Altitude Reference, shown
in the G3X Autopilot Status Box, is independent of the Selected Altitude,
displayed above the Altimeter. Altitude Hold Mode active is indicated by a
green 'ALT' annunciation in the G3X Autopilot Status Box.
Altitude Hold Mode is automatically armed when in Selected Altitude
Capture Mode. Selected Altitude Capture Mode automatically transitions to
Altitude Hold Mode when within 50 feet of the Selected Altitude. In this case,
the Selected Altitude becomes the Altitude Reference.
CHANGING THE ALTITUDE REFERENCE
When operating in Altitude Hold Mode, the Altitude Reference can be
adjusted in the following ways:
190-01115-00 Rev. K Garmin G3X Pilot's Guide
AFCS
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