Dead Reckoning - Garmin GTN 725 Pilot's Manual

1.10

Dead Reckoning

Dead reckoning is a feature that enables the GTN to provide limited navi-
gation using the last known position and speed after a loss of GPS navigation
while on an active flight plan.
CAUTION: Navigation using dead reckoning is only an estimate and
should not be used as the sole means of navigation. Use other means of
navigation, if possible.
Dead reckoning becomes active after a loss of GPS position while navigating
using an active flight plan and the flight phase is either En Route (ENR) or
Oceanic (OCN).
"DR" will be overlayed on the ownship icon. The To/From flag is removed
from the CDI. The Dead Reckoning annunciator (DR) appears on the lower
left side of the map display and will replace ENR or OCN when a GPS position
is unavailable and the unit is in Dead Reckoning mode. All external outputs
dependent on GPS position are flagged.
Terrain will be noted as not available and new terrain advisory pop-ups will
not occur. Traffic and StormScope information will not be shown on the Map
page, but will continue to be available on their own dedicated pages. XM weather
will still be available on the Map page.
Dead Reckoning mode will continue until GPS position is restored, when GPS
navigation is restored Dead Reckoning mode is exited. The DR annunciations
will be removed and GPS information will be used to compute navigation related
information for the current flight phase.
Dead Reckoning is only allowed in En Route and Oceanic phases of flight.
If the unit is in a Terminal or Approach phase of flight when Dead Reckoning
takes place, "No GPS Position" will be displayed on the map pages and all
navigation data will be dashed. If you are operating in Dead Reckoning mode
and a transition to Terminal or Approach phases of flight would occur from the
projected Dead Reckoning position, Dead Reckoning mode will be discontinued.
"No GPS Position" will be displayed on the map pages and all navigation data
will be dashed.
190-01007-03 Rev. C GTN 725/750 Pilot's Guide
Foreword
Getting
Started
Audio &
Xpdr Ctrl
Com/Nav
FPL
Direct-To
Proc
Charts
Wpt Info
Map
Traffic
Terrain
Weather
Nearest
Services/
Music
Utilities
System
Messages
Symbols
Appendix
1-19
Index