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Section 1
TIS Operation and Symbology
PART ONE:
TRAFFIC INFORMATION SERVICE (TIS) INTERFACE
Section 1: TIS Operation and Symbology
TIS Operation
NOTE: Part One of this Addendum assumes the user has experience operating the 400/500
Series units and the Garmin GTX 330 Transponder.
The Traffic Information Service (TIS) provides a graphic display of traffic advisory information in the
cockpit for non-TCAS equipped aircraft. TIS is a ground-based service providing relative location of all
ATCRBS Mode A and Mode C transponder-equipped aircraft within a specified service volume. The TIS
ground sensor uses real-time track reports to generate traffic notification. TIS Traffic display is available to
aircraft equipped with a Mode S Data Link such as the Garmin GTX 330 Transponder. TIS Traffic from a
GTX 330 Transponder can then be displayed on a Garmin 400/500 Series unit. Surveillance data includes
all transponder-equipped aircraft within the coverage volume. Aircraft without an operating transponder
are invisible to TIS. TIS displays up to eight traffic targets within 7 nautical miles horizontally from 3000
feet below to 3500 feet above the requesting aircraft.
How TCAS differs from TIS
—the main
difference between TIS and TCAS is the source
of surveillance data. TCAS uses an airborne
interrogator with a half-second update rate,
while TIS uses the terminal Mode S ground
interrogator and its Data Link to provide about
a five-second update rate. The range accuracy of
TIS and TCAS is similar.
TIS Coverage Volume (not to scale)
7.0 nm
3,500 ft
3,000 ft
