The EFIS-D10A/EFIS-D100's attitude algorithm is normally aided by pitot-based airspeed information. If the EFIS’s airspeed source becomes unavailable, the EFIS will automatically use GPS ground speed to continue to display accurate attitude. In STC-approved installations, the GPS-251 is a required component. In experimental/LSA installations, the GPS-251 will enable GPS ground track mode to the Autopilot when servos are installed.

Compatibility: Only the GPS-251 is compatible with D10/D100 series products. Other Dynon GPS products - including the SV-GPS-250 and SV-GPS-2020 - are not compatible with the D10/D100 series.