Garmin G3X Pilot’s Guide 190-01115-00 Rev. K244Hazard AvoidanceSystemOverviewFlightInstrumentsEISCNSInterfaceGPSNavigationFlightPlanningHazardAvoidanceAdditionalFeaturesAFCSAnnun/AlertsAppendixIndexGARMIN GTS 800 TRAFFIC (OPTIONAL)WARNING: Do not rely solely upon the display of traffic information fortraffic avoidance maneuvering. The GTS 800 Traffic Advisory System (TAS) isintended for advisory use only to aid the pilot in visually acquiring traffic. Noavoidance maneuvers should be based solely upon TAS traffic information.It is the responsibility of the pilot in command to see and maneuver to avoidtraffic.NOTE: Pilots should be aware of TAS system limitations. TAS systemsrequire transponders of other aircraft to respond to system interrogations.If the transponders do not respond to interrogations due to phenomenasuch as antenna shading or marginal transponder performance, traffic maybe displayed intermittently, or not at all. Aircraft without altitude reportingcapability are shown without altitude separation data or climb descent indi-cation. Pilots should remain vigilant for traffic at all times.NOTE: TIS-A is disabled when TAS installed.The optional Garmin GTS 800 is a Traffic Advisory System (TAS). It enhances flightcrew situational awareness by displaying traffic information for transponder-equippedaircraft. The system also provides visual and aural traffic alerts including voiceannouncements to assist in visually acquiring traffic.The GTS 800 is capable of tracking up to 45 intruding aircraft equipped withMode A or C transponders, and up to 30 intruding aircraft equipped with Mode Stransponders. A maximum of 30 aircraft with the highest threat potential can bedisplayed simultaneously. No TAS surveillance is provided for aircraft without operatingtransponders.THEORY OF OPERATIONWhen the GTS 800 is in Operating Mode, the unit interrogates the transponders ofintruding aircraft while monitoring transponder replies. The system uses this informationto derive the distance, relative bearing, and if reported, the altitude and vertical trendfor each aircraft within its surveillance range. The GTS 800 then calculates a closurerate to each intruder based on the projected Closest Point of Approach (CPA). If theclosure rate meets the threat criteria for a Traffic Advisory (TA), visual and aural alertingis provided.
