Garmin GNX 375, Pilot'S Manual

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Navigation
190-02207-02 Rev. B GPS 175/GNX 375 Pilot’s Guide 3-75
LPV APPROACH
Localizer performance with vertical guidance. Similar to flying the standard ILS
approach.
This segment describes a typical LPV approach sequence and the necessary pilot
actions.
Within 31 nm of destination:
•
Mode switches from En Route to Terminal
•
CDI scale transitions from 2.0 nm to 1.0 nm, full-scale deflection
Approaching initial approach fix:
•
Waypoint message annunciates
•
Time to Turn advisory annunciates and 10 second timer counts down as the
distance approaches zero
2.0 nm from final approach fix:
•
CDI scaling tightens from 1 nm to the approach-defined angular full-scale
deflection
60 seconds before final approach fix:
•
System verifies GPS position integrity is within approach limits
If GPS integrity exceeds the horizontal and/or vertical alarm limits:
•
Approach downgrades to non-precision
•
“LNAV” annunciates on Map to inform of the change if there are LNAV
minimums for the approach
•
Advisory message: ”GPS approach downgraded. Use LNAV minima.”
•
Glideslope indication disappears
•
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
After the aircraft passes final approach fix:
•
Approach aborts due to a loss of WAAS integrity
•
Pilot captures the glideslope (method is same as for ILS glideslope)