11 - MESSAGESABBREVIATIONS &NAV TERMS193190-00356-00 Rev GNavigation TermsThe following navigation terms are used on the400W-series and in this Pilot’s Guide:WPT 1XTKNORTHWPT 2BRGGSDISAIRPLANEDTKTRKALT (altitude)— Height above mean sea level (MSL).BRG (bearing)— The compass direction from yourpresent position to a destination waypoint.CAS (calibrated airspeed)— Indicated airspeed cor-rected for instrument errors.CUM (cumulative)— The total of all legs in a flightplan (such as “cumulative distance”).DIS (distance)— The geodesic path from your pres-ent position to a destination waypoint.DTK (desired track)— The desired course betweenthe active “from” and “to” waypoints.EFF (efficiency)— A measure of fuel consumption,expressed in distance per fuel units (e.g., nauticalmiles per gallon).ENDUR (endurance)— Flight endurance, or totalavailable flight time based upon available fuel.EPU (estimated position uncertainty)— A measureof satellite geometry quality and additional factors,expressed as a horizontal position error in feet ormeters.ESA (en route safe altitude)— The recommendedminimum altitude within ten miles, left or right, ofyour desired course on an active flight plan or direct-to.ETA (estimate time of arrival)— The estimated timeat which you will reach your destination waypoint,based upon current speed and track.ETE (estimated time en route)— The time it willtake to reach the destination waypoint, from presentposition, based upon current ground speed.FF (fuel flow)— The fuel flow rate, expressed in fuelunits per time (e.g., gallons per hour).FOB (fuel on board)— The total amount of usablefuel on board the aircraft.Geodesic — an arc path that follows the shortest dis-tance along an ellipsoid model of the earth (WGS-84).A geodesic is more accurate than a “great circle” whichassumes a perfect sphere model of the earch.GS (ground speed)— The velocity you are travellingrelative to a ground position.hDG (heading)— The direction an aircraft ispointed, based upon indications from a magneticcompass or a properly set directional gyro.IND (indicated)— Information provided by properlycalibrated and set instrumentation in the aircraft panel(e.g., “indicated altitude”).
