Garmin gns 500w Manuale Utente

59

190-00356-00 Rev E

Dead reckoning is the process of continuing navi-

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. 

Dead reckoning becomes active after a loss of GPS
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/
From flag is removed from the CDI. The Dead Reckon-
ing annunciator (DR) appears on the left side of the
map display when 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-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-
cated pages. XM weather will still be available on the
Map page. 
Dead Reckoning mode will continue until GPS posi-
tion 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 flight modes. If the unit is in a Terminal or 
Approach flight mode 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 flight modes would occur from 
the projected Dead Reckoning position, Dead Reckon-
ing mode will be discontinued. “No GPS Position” will 
be displayed on the map pages and all navigation data 
will be dashed. 

Dead Reckoning