Garmin GTN 625Xi, Pilot'S Manual

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5-88 Pilot’s Guide 190-02327-03 Rev. C
Hazard Awareness
TCAS II TRAFFIC SYMBOLS
Traffic information is for advisory use only. The pilot is responsible for identifying and
avoiding traffic conflict. The TCAS II system categorizes detected traffic into four
groups of increasing collision threat potential. Lowest threat is OT and the highest is
RA.
TCAS II WITH ADS-B
NOTE
Aircraft that are surveilled only by ADS-B In will not trigger a TCAS resolution advisory.
TCAS II interrogates Mode-S transponder data while automatically receiving ADS-B
position and velocity information directly from a comparably equipped aircraft target.
For preciseness, the system correlates between two data sources and the system
displays the traffic information for the source determined to be the most accurate.
Traffic that is not correlated (i.e., only detected by one system but not the other) is
also displays for the flight crew. This may occur, for example, if another aircraft is
beyond the surveillance range of the TCAS II, but it is still receiving position and
velocity information from other ADS-B equipped aircraft. The traffic correlation
feature improves the accuracy of the traffic displayed, while reducing the occurrence
of displaying a single target twice.
OT
Other non-threatening traffic.
PA
Traffic is not currently a threat, but is within 6 nm and
±1,200 feet of the own-aircraft altitude.
TA
Indicates traffic is within 20-48 seconds of a potential collision
area.
Off-scale TA
Traffic is beyond the selected map range and the system
displays a half-TA symbol at the edge of the map at the
approximate relative bearing of the TA traffic. If TA traffic
subsequently meets the criteria for an RA, the system issues
an RA.
RA
Indicates traffic is within 15-35 seconds of a potential collision
area.
Off-scale RA
If RA traffic is beyond the selected map range, the system
displays a half-RA symbol at the edge of the map positioned
at the approximate relative bearing to the RA traffic.