Garmin Flight Deck 100 Manuel D’Utilisation

190-00728-04  Rev. A

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During a heading change of greater than 105˚ with respect to the course, the CDI on the Arc HSI 

switches to the opposite side of the deviation scale and displays reverse sensing.

The Course Deviation Indicator (CDI) moves left or right from the course pointer along a lateral deviation 

scale to display aircraft position relative to the course.  If the course deviation data is not valid, the CDI is not 
displayed.

The CDI can display two sources of navigation: GPS or NAV (VOR/LOC). The color indicates the current

navigation source: magenta for GPS or green for VOR and LOC.  The full scale limits for the CDI are defined by 
a GPS-derived distance when navigating GPS.  When navigating using a VOR or localizer (LOC), the CDI has 
the same angular limits as a mechanical CDI.  If the CDI exceeds the maximum deviation on the scale (two dots) 
while navigating with GPS, the crosstrack error (XTK) is displayed below the white aircraft symbol.