Garmin GPS 175 Pilot's Manual page 154

Navigation
If pilot exceeds the horizontal alarm limits:
•
Approach downgrades to non-precision
•
"LNAV" annunciates on Map to inform of the change
•
Advisory message: "GPS approach downgraded. Use LNAV minima."
•
Pilot continues approach using LNAV non-precision minimums, if applicable
If GPS integrity does not meet the non-precision horizontal alarm limits:
•
Advisory message: "Abort Approach. GPS approach is no longer available."
•
Pilot acknowledges message
•
Unit reverts to terminal limits of 1 nm to support navigation to the missed
approach
If the approach indicates "LP+V," then advisory vertical guidance may be
removed without annunciation. This is due to the vertical guidance not being
within tolerances.
This does not constitute a downgrade. You may still fly the approach to LP
minimums.
When crossing the final approach fix:
•
Waypoint sequences to the missed approach point
(e.g., RW31, the runway threshold)
•
Pilot flies toward missed approach point, keeping the needle on the external
CDI (or HSI) at center, observing published altitude minimums
•
Final course segment becomes the active flight plan leg on Map
Approaching missed approach point:
•
Advisory message: "Arriving at Waypoint."
At the missed approach point:
•
Pilot initiates missed approach, if necessary
3-78 GPS 175/GNX 375 Pilot's Guide 190-02207-02 Rev. B