Garmin GTS 855 User Manual

GTS 8XX Series

Pilot’s Guide
Traffic Advisory System

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December 2009 Printed in the U.S.A.

LIMITED WARRANTY

This Garmin product is warranted to be free from defects in materials or workmanship for two years from
the date of purchase. Within this period, Garmin will, at its sole option, repair or replace any components
that fail in normal use. Such repairs or replacement will be made at no charge to the customer for parts
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Garmin GTS 8XX Series Traffic Advisory System

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WARNINGS, CAUTIONS, AND NOTES

WARNING: The GTS 8XX Series Traffic Advisory System (TAS and TCAS I)
is intended for advisory use only to aid the pilot in visually acquiring
traffic. No avoidance maneuvers should be based solely upon TAS traffic
information. It is the responsibility of the pilot in command to see and
maneuver to avoid traffic.

NOTE: Pilots should be aware of TAS/TCAS system limitations. TAS/TCAS
systems require intruder transponders to respond to system interrogations.
If an intruder transponder does not respond to interrogations due to
antenna shading or marginal transponder performance, it will not be
displayed, or display may be intermittent. Pilots should remain vigilant
for traffic at all times when using TAS/TCAS systems for non-transponder
equipped airplanes or unresponsive airplanes.

TSO COMPLIANCE

GTS Unit Product Description Applicable TSO

GTS 800 Low Power TAS C147, C166a
GTS 820 High Power TAS C147, C166a
GTS 850 TCAS I C118, C166a

Table 1 GTS 8XX Series Family TSO Compliance

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Contents

LIMITED WARRANTY ........................................................................................i

Warnings, Cautions, and Notes .......................................................................ii

TSO Compliance..............................................................................................ii

Product Description ........................................................................................2

Compatible Display Units .................................................................................. 4

GTS 800........................................................................................................... 5

GTS 820........................................................................................................... 5

GTS 850........................................................................................................... 5

Antennas ......................................................................................................... 5

General Antenna Information .................................................................... 5

GTS 8XX Series Antenna Configurations .................................................... 6

GA 58 Directional Antenna ........................................................................ 6

Bottom Mounted Directional Antenna (optional) ........................................ 6

Bottom Mounted Monopole Antenna (optional) ......................................... 7

GPA 65 PA / LNA Module (GTS 820 & 850 only) ............................................... 7

Operation .......................................................................................................8

GTS 8XX Series Traffic ....................................................................................... 8

Theory of Operation .......................................................................................... 8

TAS/TCAS Surveillance Volume .................................................................. 8

TAS/TCAS Symbology ................................................................................ 9

GTS 8XX Series Sensitivity Level ............................................................... 11

Traffic Advisory (TA) Alerting Conditions ................................................... 12

TAS/TCAS Alerts ...................................................................................... 13

System Test ............................................................................................. 14

Power-Up .............................................................................................. 15

System Status ......................................................................................... 15

Q and A .........................................................................................................17

Glossary ........................................................................................................19

Index .............................................................................................................20

Garmin GTS 8XX Series Traffic Advisory System

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PRODUCT DESCRIPTION

The GTS 8XX Series Traffic Advisory System (TAS) and Traffic Collision
Avoidance System (TCAS I) uses active interrogations of Mode A/C/S transponders
to provide Traffic Advisories to the pilot independent of the air traffic control
system. The system also uses passive surveillance by means of an Automatic
Dependent Surveillance – Broadcast (ADS-B) receiver which is enabled when
installed with an ADS-B link transmit class of equipment.

Figure 1 GTS 8XX LRU

The GTS 8XX Series of Traffic Advisory System (TAS) or Traffic Alert and
Collision Avoidance System (TCAS I) microprocessor-based sub-systems products
consist of the GTS 800, GTS 820 and GTS 850. The GTS 800 TAS product consists
of one LRU which has low power (40 Watts) transmit capability, and one GA 58,
or other Garmin-approved, directional antenna. The GTS 820 TAS and GTS 850
TCAS I products include one LRU paired with one GPA 65 PA/LNA Amplifier
Module, which allows high power (250W) transmit capability, and one GA 58 or
other Garmin-approved directional antenna. An optional second antenna may also
be installed with these systems. The optional second bottom mounted antenna
may be omnidirectional or a Garmin approved directional antenna.

For targets equipped with a 1090 MHz ADS-B transmit class of equipment, the
GTS 8XX series combines active (interrogated) and passive (ADS-B) surveillance
data to enhance the accuracy of target position on the display. The systems use
Garmin’s CLEAR CASTM technology to correlate ADS-B and actively interrogated
targets to provide pilots with the most accurate target position. Passive ADS-B
surveillance is enabled when the GTS 8XX is installed with an ADS-B transmit
class of equipment.

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Garmin GTS 8XX Series Traffic Advisory System

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The GTS 8XX Series provides for expanded audio messaging in an ATC-like
verbal format: “Traffic. One o’clock. High (or Low or Same Altitude). Two miles.”
If surveillance bearing information is not available on the intruder, “Traffic, No
Bearing” is called out.

Bearing may be derived from either the top or bottom directional antenna
depending upon which antenna hears the response. A directional antenna is used
to derive bearing to the intruder aircraft, which is displayed with relative altitude
to own aircraft. Top antenna transmitted interrogations are directional, reducing
the number of transponders that receive the interrogation thus reducing potential
garble on the 1090 MHz band.

Note: GTS 8XX is used throughout this manual to refer to the GTS 800,
820, or 850 products. When a feature is unique to the GTS 800, 820, or
850 it will be specifically referenced as such.

Product GTS 800 GTS 820 GTS 850

Traffic Advisory System (TAS) X X
Traffic Alert and Collision Avoidance System

X

(TCAS I)
LRU X X X
GPA 65 PA/LNA X X
1090 ES ADS-B Receiver X X X
Transmit Power (Watts) 40 250 250
Top-Mounted Garmin-Approved Directional

X X X

Antenna
Optional Bottom-Mounted Garmin-Approved

X X X

Directional or Omnidirectional Antenna

Table 2 GTS 8XX Series Family Product Description

The GTS 8XX Series does not contain a display, but transmits traffic data to a
Garmin or third party multi-function display that is capable of displaying traffic
data. More information is located in the installation manual. The GTS 8XX Series
supplies data to a traffic display to indicate the presence and location of intruder
aircraft. The information provides the crew with the intruder’s range, bearing,
and, for altitude reporting intruders, relative altitude and vertical trend. TCAS I
symbology as defined in the FAA Advisory Circular entitled “Airworthiness

Garmin GTS 8XX Series Traffic Advisory System

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Approval of Traffic and Collision Avoidance Systems (Active TCAS I)” is utilized
to depict traffic information.

Compatible Display Units

The following table lists compatible display units. As products may
continually be added to the list of compatible display units, always refer to the
GTS 8XX Installation Manual for a complete list. Some displays may require
the purchase and installation of additional modules and/or software to support
traffic displays. Check with your installer to ensure an existing display supports
traffic prior to installation.

Manufacturer Model

Garmin GMX 200/MX20
Garmin GNS 400/500 Series
Garmin GNS 400W/500W Series
Garmin GNS 480
Garmin GDU 620
Avidyne EX500 (MFD Only)
Honeywell Bendix/King KMD 550/850
Sandel SN3500/SN4500

Table 3 GTS 8XX Series Compatible Display Units

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Garmin GTS 8XX Series Traffic Advisory System

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GTS 800

The GTS 800 is a TAS system that can track up to 45 Mode A/C/S targets,
and display up to 30 intruder threats at a time, depending on the display being
utilized. Offering 40 watts of transmit power, a ±10,000 foot vertical separation
maximum, and an active interrogation range of up to 12 NM in the forward
direction, the GTS 800 system will interface with a variety of compatible system
displays in the cockpit.

GTS 820

The GTS 820 is a TAS system that can track up to 45 intruding aircraft
equipped with Mode A/C transponders, and up to 30 intruders equipped with
Mode S transponders. A GTS 820 TAS has an active surveillance range of up to
40 NM in the forward direction, dependent upon interference limiting techniques
based on the number of TCAS II interrogators in the area. Interrogation power
and range in the left, right, and aft quadrants is reduced in a manner similar to
TCAS II systems. It includes a GPA 65 PA/LNA Module that is remotely installed
near the top directional antenna to boost the interrogation range.

GTS 850

The GTS 850 is a fully compliant TCAS I certified system. Operational
capabilities are similar for airborne traffic surveillance for both the GTS 820 and
GTS 850 systems.

Antennas

General Antenna Information

A top-mounted directional antenna is used to derive bearing to the intruder
aircraft. Top antenna transmitted interrogations are directional, reducing the
number of transponders that receive the interrogation thus reducing potential
garble on the 1090 MHz band.

Optional bottom monopole or directional antenna transmit interrogations are
omnidirectional. Intruder bearing can be determined from the top directional
antenna or an optional bottom directional antenna for retractable gear aircraft.

Garmin GTS 8XX Series Traffic Advisory System

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GTS 8XX Series Antenna Configurations

• Toponlydirectionalantenna.

• Top directionalwithbottom monopoleantennas(recommended forxed

gear aircraft) provides improved intruder visibility. The type of antenna used
will be primarily limited by the amount of space available on the bottom
of the airplane. Any aircraft that can utilize the directional antenna on the
bottom would benefit from its use.

• Top directional with bottom directional antennas (recommended for

retractable gear aircraft) provides benefit of intruder bearing visibility for
targets that are shaded from the top directional antenna.

GA 58 Directional Antenna

The GA 58 directional four element antenna is included with the basic GTS
system to provide altitude, distance, and bearing of threat aircraft. A single antenna
installation uses top-mounted placement. A second GA 58 may be bottom­mounted to optimize coverage.

Figure 2 GA 58 Directional Antenna

Bottom Mounted Directional Antenna (optional)

A directional antenna may be used as an additional antenna for bottom­mounting to reduce shading and provide altitude and distance of threat aircraft.
Interrogations from the bottom directional antenna are transmitted in an
omnidirectional pattern, but it still allows bearing determination from replies
received on the bottom antenna.

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Garmin GTS 8XX Series Traffic Advisory System

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Bottom Mounted Monopole Antenna (optional)

The addition of an optional bottom-mounted monopole antenna will improve
visibility of intruder aircraft by reducing shading and providing altitude and
distance of threat aircraft. Bearing cannot be determined from replies received
on a bottom-mounted monopole antenna.

Figure 3 Bottom-Mounted Monopole Antenna

GPA 65 PA / LNA Module (GTS 820 & 850 only)

The GPA 65 is a combined Power Amplifier and Low Noise Amplifier module
used in the higher power GTS 820 and 850.

Figure 4 GPA 65 PA/LNA Module

Garmin GTS 8XX Series Traffic Advisory System

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OPERATION

GTS 8XX Series Traffic

The Garmin GTS 8XX Series unit is a Traffic Advisory System (TAS - GTS 800
and GTS 820) or Traffic Alert and Collision Avoidance System (TCAS I - GTS 850).
The GTS 8XX Series enhances flight crew situational awareness by displaying traffic
information for transponder-equipped aircraft. The GTS 8XX Series also provides
visual and aural traffic alerts including voice announcements to assist in visually
acquiring traffic. The GTS 800 and GTS 820 are TAS systems, the GTS 850 is a
TSO-approved TCAS I system. The GTS 8XX uses active interrogations of Mode
A/C/S transponders to provide Traffic Advisories.

Theory of Operation

When the GTS 8XX Series is in Operating Mode, the unit interrogates the
transponders of intruding aircraft while monitoring transponder replies. The
GTS 8XX Series uses this information to derive the distance, relative bearing, and
if reported, the altitude and vertical trend for each aircraft within its surveillance
range. The GTS 8XX Series then calculates a closure rate to each intruder based
on the projected Closest Point of Approach (CPA). If the closure rate meets the
threat criteria for a Traffic Advisory (TA), visual and aural alerting is provided.

TAS/TCAS Surveillance Volume

The GTS 8XX Series surveillance system monitors the airspace within ±10,000
feet of own altitude. Under ideal conditions, the unit scans transponder traffic
up to 40 NM (GTS 820 and GTS 850) or 12 NM (GTS 800) in the forward
direction using top and bottom-mounted antennas similar to TCAS II systems.
In areas of greater transponder traffic density or when TCAS II systems are
detected, the GTS 820 and GTS 850 systems automatically reduce interrogation
transmitter power (and therefore range) in order to limit potential interference
from frequency congestion. The GTS 800’s range is 12 NM in the forward direction
and the maximum interrogation transmitter power remains constant. There is
also a minimum alerting threshold for range to allow alerting in situations where
traffic is slowly converging. Alerting may be caused by closure rate or minimum
distance to the intruder.

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Garmin GTS 8XX Series Traffic Advisory System

190-00587-02 Rev. A

TAS/TCAS Symbology

The GTS 8XX Series supports displays that depict intruding traffic using the
symbols shown in the following table. Refer to the documentation for the specific
display to confirm the supported symbology. Symbol colors may vary depending
on the display product.

TAS Symbol Description

Non-Threat Traffic
(intruder is beyond 6 NM and greater than 1200 feet vertical

separation)
Proximity Advisory (PA)

(intruder is within 6 NM and less than 1200 feet vertical separation)
Traffic Advisory (TA)

(closing rate, distance, and vertical separation meet TA criteria)

Traffic Advisory Off Scale

Table 4 TAS Intruder Symbol Description

A Traffic Advisory (TA), displayed as a yellow circle, alerts the crew to a
potentially hazardous intruding aircraft if the closing rate, distance, and vertical
separation meet TA criteria. A Traffic Advisory that is beyond the selected display
range is indicated by a half TA symbol at the edge of the screen at the relative
bearing of the intruder.

A Proximity Advisory (PA), displayed as a solid white diamond, indicates the
intruding aircraft is within ±1200 feet and is within a 6 NM range, but is still not
considered a TA threat.

A non-threat symbol, shown as an open white diamond, is displayed for all
other traffic beyond 6 NM that does not meet the criteria to be a TA or PA.

Relative altitude, when available, is displayed above or below the corresponding
intruder symbol in hundreds of feet. When this altitude is above own aircraft,
it is preceded by a “+” symbol; a minus sign “-” indicates traffic is below own
aircraft.

A vertical trend arrow to the right of the intruder symbol indicates climbing or
descending traffic with an upward or downward-pointing arrow respectively.

Garmin GTS 8XX Series Traffic Advisory System

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Intruder Altitude
and Vertical Trend

Figure 5 Intruder Altitude and Vertical Trend Arrow

The GTS 8XX Series automatically suppresses the display of altitude-reporting
aircraft on the ground under either of the following conditions:

• On-groundaircraftisequippedwithaModeS transponder that reports the
on-ground state.

• On-ground aircraft is equipped with a Mode C transponder, and own
aircraft’s radar altimeter (if installed) is displaying 1700 feet AGL or less.

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Garmin GTS 8XX Series Traffic Advisory System

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GTS 8XX Series Sensitivity Level

The GTS 8XX Series issues Traffic Advisories according to the current Sensitivity
Level (SL). To prevent nuisance alerts near airports, the GTS 8XX Series has two
sensitivity levels available, Sensitivity Level A (SLA) and Sensitivity Level B (SLB).
Refer to Table 5 for Sensitivity Level definitions. SLA is used to reduce sensitivity
levels in airport environment and avoid nuisance traffic alerts.

The logic for choosing the sensitivity level is based on aircraft configura­tion. SLA is determined according the following order:

1. Ownship is below 2,000 feet AGL (if equipped with a radio altimeter)

2. Landing gear is extended (no radio altimeter is installed on retractable gear
aircraft)

3. Ground speed is below 120 knots (no radio altimeter installed in a fixed-gear
aircraft)

The GTS 8XX Series will remain in SLB at all other times. In the event a
fixed-gear aircraft is not equipped with a radio altimeter and ground speed is not
available, the GTS 8XX Series will remain in SLB at all times.

Note: If the GTS 8XX Series is interfaced to a radio altimeter, or if the gear/

wheel is configured as fixed, the system will ignore the GEAR DOWN AND
LOCKED discrete input.

In both SLA and SLB, audio alerts are suppressed only under the following
conditions:

1. If radio altimeter is installed and own altitude is less than 400 feet AGL.

2. If no radio altimeter is installed in a retractable gear aircraft and gear is
extended.

Garmin GTS 8XX Series Traffic Advisory System

11190-00587-02 Rev. A

Traffic Advisory (TA) Alerting Conditions

Sensitivity

Level

Intruder Altitude

Available

TA Alerting Conditions

A Yes Intruder closing rate provides less than 20

seconds of vertical and horizontal separation.
Or:
Intruder closing rate provides less than 20

seconds of horizontal separation and vertical
separation is within 600 feet.

Or:
Intruder range is within 0.2 NM and vertical

separation is within 600 feet.

A No Intruder closing rate provides less than 15

seconds of separation.

B Yes Intruder closing rate provides less than 30

seconds of vertical and horizontal separation.
Or:
Intruder closing rate provides less than 30

seconds of horizontal separation and vertical
separation is within 800 feet.

Or:
Intruder range is within 0.55 NM and vertical

separation is within 800 feet.

B No Intruder range is less than 20 seconds.

Table 5 TA Sensitivity Level and TA Alerting Criteria

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Garmin GTS 8XX Series Traffic Advisory System

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TAS/TCAS Alerts

When the GTS 8XX Series detects a new TA, the following occur:

• A single “Trafc!” voice alert is generated, followed by additional voice

information about the bearing, relative altitude, and approximate distance
from the intruder that triggered the TA. The announcement “Trafc!
12 o’clock, high, four miles,” would indicate the traffic is in front of own
aircraft, above own altitude, and approximately four nautical miles away.

• ATAisannunciatedonthedisplayasaTAsymbolorannunciation.Refer

to the display pilot’s guide for details.

If the bearing of TA traffic cannot be determined, a yellow text banner will
be displayed on the Traffic Page instead of a TA symbol. The text will indicate
“TA” followed by the distance, relative altitude, and vertical trend arrow for the
TA traffic, if known.

A TA will be displayed for at least eight seconds, even if the condition(s) that
initially triggered the TA are no longer present.

Bearing Relative Altitude Distance

“One o’clock” through
“Twelve o’clock”
or “No Bearing”

Table 6 TA Descriptive Voice Announcements

No-Bearing TA Traffic
Annunciation

Figure 6 Traffic Annunciation

“High”, “Low”, “Same
Altitude” (if within 200
feet of own altitude), or
“Altitude not available”

Garmin GTS 8XX Series Traffic Advisory System

“Less than one mile”,
“One Mile” through “Ten

Miles”, or “More than ten
miles”

13190-00587-02 Rev. A

System Test

NOTE: GTS 8XX Series traffic surveillance is not available during the system

test. Use caution when performing a system test during flight.

The GTS 8XX Series provides a system test mode to verify the TAS system is
operating normally. The test takes ten seconds to complete. When the system test
is initiated, a test pattern of traffic symbols is displayed on the Traffic Page. If the
system test passes, the aural announcement “TAS System Test Passed” is heard,
otherwise the system announces “TAS System Test Failed.” For the GTS 850,
the aural announcement is “TCAS System Test Passed/Failed.” When the system
test is complete, the GTS 8XX Series enters Standby Mode. The system may be
installed so that the system test is unavailable during flight.

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Figure 7 Self-Test Mode

Garmin GTS 8XX Series Traffic Advisory System

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Power-Up

NOTE: The GTS 8XX Series automatically transitions from STANDBY to

OPERATE mode eight seconds after takeoff. The unit also automatically
transitions from OPERATE to STANDBY mode 24 seconds after landing.

After power-up, the GTS 8XX Series is in Standby Mode. The GTS 8XX Series
must be in Operating Mode for traffic to be displayed and for TAs to be issued.

System Status

The traffic mode is annunciated on the display product. The symbology
may vary by display product. See the particular pilot’s guide for specific details.

Traffic Display

Enabled Icon
(Other Maps)

Mode

Traffic Mode Annunciation

(Traffic Page)

Self-test Initiated TEST

Operating OPERATING

Standby

(also shown in white in center of page)

STANDBY

Failed* FAIL

Table 7 Example TAS/TCAS Modes

If the traffic unit fails, an annunciation as to the cause of the failure is shown
on the display product. During a failure condition, the Operating Mode cannot
be selected.

Traffic Map Page Annunciation Description

NO DATA Data is not being received from the TAS/

TCAS I unit

DATA FAILED Data is being received from the TAS/

TCAS I unit, but the unit is self-reporting
a failure

FAILED Incorrect data format received from the

TAS/TCAS I unit

Table 8 TAS/TCAS Failure Annunciations

Garmin GTS 8XX Series Traffic Advisory System

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The annunciations to indicate the status of traffic information appear in a
banner on the traffic display. The annunciations may vary by display product.
See the particular pilot’s guide for specific details.

Traffic Status Banner Annunciation Description

TA OFF SCALE A Traffic Advisory is outside the selected

display range.
Annunciation is removed when traffic

comes within the selected display range.

TA X.X ± XX 

System cannot determine bearing of
Traffic Advisory.

Annunciation indicates distance in NM,
altitude separation in hundreds of feet,
and altitude trend arrow (climbing/
descending).

Table 8 TAS Traffic Status Annunciations

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Garmin GTS 8XX Series Traffic Advisory System

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Q AND A

What are the benefits of ADS-B?

1090 MHz Extended Squitter ADS-B data contains additional information
about a target aircraft including flight ID, latitude, longitude, barometric and
geometric altitude, velocity, and direction.

This provides precise location information about the target aircraft. Targets
within the active surveillance range that are correlated with ADS-B data are dis­played with much greater accuracy as a result of this.

When is ADS-B (passive surveillance) available?

Passive surveillance functionality is available when the GTS 8XX system is
installed with an ADS-B link transmit class of equipment. Target aircraft must
be equipped with a 1090 MHz ADS-B transmit class unit to provide ADS-B data
for passive surveillance.

How do we correlate the ADS-B data with the TAS/TCAS I data?

The GTS 8XX Series correlates TAS or TCAS I range, altitude, and bearing data
with internally received 1090 Extended Squitter ADS-B data when available, using
the precision information from ADS-B to determine the location of the target.

The TAS/TCAS I data, either correlated, or uncorrelated if target aircraft is
not equipped with an ADS-B transmitter, is sent to a display such as a G600 or
G1000 Control/Display Unit, GNS 430, GNS 480, GNS 530, MX 20, GMX 200,
or a third-party device.

How are active and passive targets displayed?

For systems that use Garmin’s High-Speed Data Bus (HSDB) to communicate
data to the display device, correlated targets will be shown with their flight ID. A
future update will include the display of track and velocity information, as well as
ground targets. Passive surveillance targets outside the active surveillance range
will also be displayed with their flight ID.

For systems that use ARINC 429 to communicate data to the display device,
ARINC 429 protocol does not exist to distinguish between correlated targets
and uncorrelated targets. For this reason only active surveillance correlated and
uncorrelated targets will be transmitted to the display device with no distinction
between the two, but with enhanced position accuracy derived from the correlated
data. Display characteristics that would distinguish the passive (ADS-B) and active
targets would require a software update to the display device.

Garmin GTS 8XX Series Traffic Advisory System

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What are the ramifications if GPS data is not available?

Own ship latitude and longitude are not known. Active surveillance still
determines target distance, bearing, and altitude (if an altitude reporter). Passive
surveillance is disabled if GPS position of own aircraft is not available. TAS/TCAS
and traffic alerting remain operational.

Is a Mode C or S transponder required for the GTS 8XX Series
installation?

Not for the GTS 800 TAS low power product, but the absence of an ADS-B
link transmit class of equipment will disallow the ADS-B receive functionality.
ADS-B requires broadcast capability which comes from ADS-B link transmit class
of equipment.

The higher power products, GTS 820 TAS and GTS 850 TCAS I, require
a Mode S transponder that is capable of obtaining the NTA count (number of
TCAS II-equipped aircraft in the active surveillance area). This is due to an inter­ference limiting requirement.

Does the GTS 8XX Series require a Garmin Extended Squitter
Mode S transponder to support all functions?

The GTS 800 requires a Garmin Extended Squitter Mode S transponder or
other complementary ADS-B link transmit class of equipment for ADS-B opera­tion.

The GTS 820 TAS and GTS 850 TCAS I require a Garmin Extended Squitter
Mode S transponder for ADS-B operation.

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Garmin GTS 8XX Series Traffic Advisory System

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GLOSSARY

AGL: Above Ground level

Active Target: Any intruder tracked by the appliance using active

interrogations

ADS-B: Automatic Dependent Surveillance – Broadcast

ATCRBS: Air Traffic Control Radio Beacon Service- A secondary

surveillance radar system having ground-based interrogators
and airborne transponders capable of operation on Modes
A and C

CLEAR CAS: Correlated Location Enhanced ADS-B Receiver Collision

Avoidance System

CPA: Closest Point Approach

GPS: Global Positioning System

LRU: Line Replaceable Unit

MHz: Mega Hertz

Mode A: A type of ATCRBS transmission which requests (via Mode

A interrogations) or reports (via Mode A replies) aircraft
identity information

Mode C: A type of ATCRBS transmission which requests (via Mode

C interrogations) or reports (via Mode C replies) aircraft
altitude information

Mode S: A type of secondary surveillance radar transmission which

contains a unique 24-bit discrete address, thus allowing
interrogations to be addressed to individual aircraft. Mode
S transmissions can be short (56 bits) or long (112 bits),
with long transmissions containing a 56-bit “message”
field.

NTA: Number of TCAS equipped targets

NM: Nautical Mile

PA: Proximate Advisory

Target: Any intruder tracked by the appliance

TA: Traffic Advisory

TAS: Traffic Advisory System

TCAS: Traffic Alert and Collision Avoidance System

Garmin GTS 8XX Series Traffic Advisory System

19190-00587-02 Rev. A

INDEX

A

ADS-B 2, 17, 18
Alerting conditions 12
Alerts 13
Annunciation 15
Antenna 5

G

GA 58 Antenna 6
Glossary 19
GPA 65 PA/LNA module 7

I

Intruder ii, 3, 5, 9, 13, 19
Intruder altitude 12

M

Mode C transponder 2, 5, 10, 18, 19
Mode S transponder 2, 5, 10, 18

O

Omni-Directional antenna 6
Operation 8

T

TCAS I ii
TCAS II 8
Theory of operation 8
TSO ii

V

Voice announcements 13

W

Warnings ii
Warranty i

P

Passive surveillance 17
Power-up 15
Product description 2
Proximity Advisory 9

Q

Q and A 17

S

Scale 9
Sensitivity level 11, 12
Surveillance volume 8
Symbology 9
Symbols 9
System status 15
System test 14

20

Garmin GTS 8XX Series Traffic Advisory System

190-00587-02 Rev. A

© 2009 GARMIN Corporation

GARMIN International, Inc.

1200 East 151st Street, Olathe, Kansas 66062, U.S.A.

Tel. [phone] or 800/800.1020

Fax [phone]

Garmin AT, Inc.

2345 Turner Rd., S.E., Salem, Oregon 97302, U.S.A.

Tel. [phone] or 800/525.6726

Fax. [phone]

Garmin (Europe) Ltd.

Liberty House, Bulls Copse Road, Hounsdown Business Park,

Southampton, SO40 9RB, U.K.

Tel. [phone]

Fax [phone]

GARMIN Corporation

No. 68, Jangshu 2nd Road, Shijr, Taipei County, Taiwan

Tel. [phone]
Fax [phone]

www.garmin.com

Part Number 190-00587-02 Rev. A