The Cross Track Error (Deviation) scale on the CDI in ForeFlight Mobile is set so that each dot represents 1 nautical mile (nm) of cross-track deviation. When deviation exceeds 2.3 nm, the dots are removed, and a numeric value for cross-track deviation is displayed on the CDI instead.
Cross-track deviation relative to the course is based on GPS position, and no terminal mode sensitivity scaling is applied.
CDI showing 1.5 nm off route.
Deviation dots are removed when over 2.3 nm off route, displaying text with deviation distance.
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