Garmin G3X Touch Pilot's Manual page 103

When the VNAV profile is defined, the pilot is informed of the progress by message
alerts. A magenta chevron (VNAV Indicator) to the left of the altimeter on the Vertical
Deviation Scale shows the VNAV profile, and a magenta chevron (Required Vertical
Speed Indicator (RVSI)) on the Vertical Speed Indicator indicates the required vertical
speed to reach the target altitude.
The Vertical Navigation feature is only available when navigating
NOTE:
a Direct-to or flight plan, and the ground speed is greater than 35 knots.
One minute prior to the initial descent point the "Approaching VNAV Profile"
message appears and the 'Estimated Time to VNAV' (on Active Flight Plan Page) goes
blank. The descent angle locks to prevent changes in speed from altering the profile.
The VNAV feature does not take into account any changes in ground speed that occur
during the transition from level flight to descent.
At 200 ft above the target altitude, the "Approaching Target Altitude" message
appears, and the VNAV indicator disappears from the PFD.
190-02472-00 Rev. D
Distance to Profile
Distance to Target
Visual Representation of VNAV
Garmin G3X Touch ™ Pilot's Guide for Certified Aircraft
Flight Instruments
Target Altitude
Airport
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