Garmin aera 795/796 Pilot’s Guide190-01194-00 Rev. CAppendix F193Overview GPS Navigation Flight Planning Hazard Avoidance Additional Features Appendices IndexAPPENDIX F: GENERAL TIS-A INFORMATIONNOTE:Aircraft without an operational transponder are invisible to TIS-A.WARNING: Do not rely solely upon the display of traffic information for collisionavoidance maneuvering. The traffic display does not provide collision avoidanceresolution advisories and does not under any circumstances or conditions relieve thepilot’s responsibility to see and avoid other aircraft.WARNING: Do not rely solely upon the display of traffic information to accuratelydepict all of the traffic within range of the aircraft. Due to lack of equipment, poor signalreception, and/or inaccurate information from aircraft or ground stations, traffic may bepresent that is not represented on the display.The Traffic Information Service (TIS-A) provides traffic advisory information to non-TAS/TCAS-equipped aircraft. TIS-A is a ground-based service providing the relativelocations of all ATCRBS (Air Traffic Control Radar Beacon System) Mode-A and Mode-Ctransponder equipped aircraft within a specified service volume. The TIS-A groundsensor uses real-time track reports to generate traffic notification. The aera 795/796displays TIS-A traffic information on the Navigation Map. Surveillance data includes alltransponder-equipped aircraft within the coverage volume. The aera 795/796 displaysup to eight traffic targets within a 7.5-nm radius, from 3,000 feet below, to 3,500 feetabove the requesting aircraft.TIS-A VS. TAS/TCASThe main difference between the Traffic Information System (TIS-A) and TrafficAdvisory (TAS) or Traffic Collision Avoidance Systems (TCAS) is the source of surveillancedata. TAS/TCAS uses an airborne interrogator with a half-second update rate, whileTIS-A utilizes the terminal Mode-S ground interrogator and accompanying data link toprovide a five-second update rate. TIS-A and TAS/TCAS have similar ranges.TIS-A LIMITATIONSTIS-A relies on surveillance of the Mode-S radar system, which is a “secondarysurveillance” radar system similar to that used by ATCRBS. Many limitations areinherent in secondary radar surveillance. Information provided by TIS-A is neither
