Garmin GTN 625 Pilot's Manual page 161

5. Sixty seconds prior to reaching the FAF, the GTN will check
the required Horizontal Alarm Limit (HAL) to ensure the
GPS position integrity is within limits to complete the LP
non-precision approach. In the event the HAL limits are
exceeded, the approach will be downgraded, when available,
indicated by "LNAV" on the moving map, otherwise the
approach will be aborted. A message will note that the
approach is downgraded and the NAV indicator will be
flagged until the message is viewed. You may continue the
approach using LNAV non-precision minimums if there are
LNAV minimums for this approach. In the rare event the GPS
HAL limits cannot meet non-precision limits, the GTN will notify
the pilot with a message to abort the approach. The GTN will
revert to terminal limits of 1.0 NM to support navigation to the
missed approach. If the approach is indicating an LP +V, it is
possible that the advisory vertical guidance could be removed
without annunciation due to the vertical guidance not being
within tolerances. This does not constitute a downgrade, and
the approach can still be flown to LP minimums.
6. As you cross the FAF, the destination sequences to the MAP.
With the needle on the external CDI (or HSI) centered, fly
toward the MAP, observing the altitude minimums dictated
by the approach plate.
7. When viewing the Map page, you'll note that the final course
segment is displayed in magenta (the active leg of the flight
plan always appears in magenta).
8. As you approach the MAP, a waypoint message ("Arriving at
Waypoint") appears on the bottom of the screen.
9. At the MAP initiate the missed approach, if necessary. Once
the GTN crosses the MAP, sequencing will be suspended.
Prepare the aircraft for missed approach operation. Touch
the Unsuspend key to sequence to the Missed Approach
procedure.
NOTE: For missed approaches with heading legs, fly manually until the
first active course leg is reached.
10. Fly the guidance provided by the GTN to the MAHP and hold.
190-01004-03 Rev. P GTN 625/635/650 Pilot's Guide
Foreword
Getting
Started
Audio &
Xpdr Ctrl
Com/Nav
FPL
Direct-To
Proc
Wpt Info
Map
Traffic
Terrain
Weather
Nearest
Services/
Music
Utilities
System
Messages
Symbols
Appendix
Index
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