XPLMSetFMSFlightPlanEntryLatLon
XPLM_API void XPLMSetFMSFlightPlanEntryLatLon(
XPLMNavFlightPlan inFlightPlan,
int inIndex,
float inLat,
float inLon,
int inAltitude);
This routine changes the entry in the FMS to a lat/lon entry with the given coordinates.