Garmin aera 795/796 Pilot’s Guide190-01194-00 Rev. AAppendix F153Overview GPS Navigation Flight Planning Hazard Avoidance Additional Features Appendices IndexAPPENDIX F: GENERAL TIS INFORMATIONNOTE:Aircraft without an operational transponder are invisible to TIS.NOTE:TIS is not intended to be used as a collision avoidance system and doesnot relieve the pilot of the responsibility to “see and avoid” other aircraft. TISshould not be used for avoidance maneuvers during instrument meteorologicalconditions (IMC) or when there is no visual contact with the intruder aircraft.The Traffic Information Service (TIS) provides traffic advisory information to non-TAS/TCAS-equipped aircraft. TIS 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 groundsensor uses real-time track reports to generate traffic notification. The aera 795/796displays TIS 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 VS. TAS/TCASThe main difference between the Traffic Information System (TIS) and Traffic Advisory(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 utilizes the terminal Mode-S ground interrogator and accompanying data link toprovide a five-second update rate. TIS and TAS/TCAS have similar ranges.TIS LIMITATIONSTIS 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 is neither betternor more accurate than the information used by ATC. TIS is intended only to assist invisual acquisition of other aircraft in visual meteorological conditions (VMC). WhileTIS is a useful aid for visual traffic avoidance, system limitations must be considered toensure proper use. No recommended avoidance maneuvers are given, nor authorized,as a direct result of a TIS intruder display or TIS advisory.
