Garmin G1000 NXi Pilot's Manual page 72

FLIGHT INSTRUMENTS
The system automatically changes from GPS to LOC navigation source and changes the CDI scaling accordingly
when all of the following occur:
• A localizer or ILS approach has been loaded into the active flight plan
• The final approach fix (FAF) is the active leg, the FAF is less than 15 nm away, and the aircraft is moving
toward the FAF
• A valid localizer frequency has been tuned
• The GPS CDI deviation is less than 1.2 times full-scale deflection
GPS steering guidance is still provided after the CDI automatically changes to LOC until LOC capture, up
to the Final Approach Fix (FAF) for an ILS approach, or until GPS information becomes invalid. Activating a
Vector-to-Final (VTF) also causes the CDI to switch to LOC navigation source. GPS steering guidance is not
provided after the change.
On some ILS approaches where the glideslope intercept point is at or in close proximity to the fix prior to
the FAF (see Figure 2-22), it is possible to be above the glideslope when the navigation source automatically
changes from GPS to LOC. The probability of this occurring varies based on air temperature.
Fix Prior to the FAF
Glideslope Intercept Point
Figure 2-22 ILS Approach with Glideslope Intercept Point at Fix Prior to the FAF
GPS CDI SCALING
When GPS is the selected navigation source, the flight plan legs are sequenced automatically and
annunciations appear on the HSI for the flight phase. Flight phase annunciations are normally shown in
magenta, but when cautionary conditions exist the color changes to amber. If the current leg in the flight plan
is a heading leg, HDG LEG is annunciated in magenta beneath the aircraft symbol.
The current GPS CDI scale setting is displayed as System CDI on the Aux - System Setup 1 Page and the
full-scale deflection setting may also be selected (2.0 nm, 1.0 nm, 0.3 nm, or Auto) from this page. If the
selected scaling is smaller than the automatic setting for enroute and terminal phases, the CDI is scaled
accordingly and the selected setting is displayed rather than the flight phase annunciation.
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Garmin G1000 NXi Pilot's Guide for the Cessna Nav III
190-02177-00 Rev. A