2 - NAV PAGES
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190-00356-00 Rev E
Dead Reckoning
Deadreckoningistheprocessofcontinuingnavi-
gation using your last known position and speed after
a loss of GPS navigation while on an active flight plan.
CAUTION: Navigation using dead reckoning is
therefore only an estimate and should not be
used as the sole means of navigation. Use other
means of navigation, if possible.
DeadreckoningbecomesactiveafteralossofGPS
position while you are navigating using an active flight
plan. A pop-up message will appear and you must
clear the message before continuing operation.
The ownship icon color is changed to yellow. The To/
FromagisremovedfromtheCDI.TheDeadReckon-
ingannunciator(DR)appearsontheleftsideofthe
map display when GPS position is unavailable and the
unitisinDeadReckoningmode.Allexternaloutputs
dependent on GPS position are flagged.
Terrain will be noted as not available and new terrain
advisory pop-ops will not occur. Traffic and Storm-
scope information will not be shown on the Map page,
but will continue to be available on their own dedi-
catedpages.XMweatherwillstillbeavailableonthe
Map page.
DeadReckoningmodewillcontinueuntilGPSposi-
tionisrestored,whenGPSnavigationisrestoredDead
Reckoningmodeisexited.TheDRannunciations
will be removed and GPS information will be used to
compute navigation related information for the current
flight phase.
DeadReckoningisonlyallowedinEnRouteand
Oceanic flight modes. If the unit is in a Terminal or
ApproachightmodewhenDeadReckoningtakes
place, “No GPS Position” will be displayed on the map
pages and all navigation data will be dashed. If you are
operatinginDeadReckoningmodeandatransitionto
Terminal or Approach flight modes would occur from
theprojectedDeadReckoningposition,DeadReckon-
ing mode will be discontinued. “No GPS Position” will
be displayed on the map pages and all navigation data
will be dashed.
Dead Reckoning