Garmin GNC 420W Pilots Guide - Page 194

SECTION 11 ADDITIONAL FEATURES TIS Audio Alerting The TIS audio alert is generated when the number of Traffic Advisories (TA) on the GNC 420 display increases from one scan to the next. For example, when the first TA appears on the TIS display, the user is alerted audibly. As long as a single aircraft remains on the TIS display, no further audio alert is generated. If a second (or more) TA appears on the display, a new audio alert is sounded. Limiting TAs reduces "nuisance" alerting due to proximate aircraft. If the number of TAs on the TIS display decreases and then increases, a new audio alert is sounded. A TIS audio alert is also generated when TIS service becomes unavailable. The volume, pitch, and duration of the audio alert (including the choice between a male or female voice) is configured during installation. The following TIS audio alerts are available: • "Traffic" - TIS traffic alert is received. • "Traffic Not Available" - TIS service is not available or out of range. TIS Symbology TIS traffic is displayed on the GNC 420 unit according to TCAS symbology on a dedicated Traffic page, and on the moving Map Page. The symbology is shown in Table 11-1 and Figures 11-2, 11-3, and 11-4. The symbology is described in Table 11-2. A Traffic Advisory (TA) symbol appears as a solid yellow circle (or half circle on the outer range ring if the traffic is outside the range of the dedicated Traffic Page). Other Traffic is displayed as hollow white (may be configured as cyan) diamonds. Altitude deviation from own (client) aircraft altitude is displayed (in hundreds of feet) for each target symbol. If traffic is above own aircraft altitude the deviation is shown above the target next to a '+' symbol. If traffic is below own aircraft altitude the deviation is shown below the target next to a '-' symbol. Altitude trend is displayed as an up arrow (> +500 fpm), down arrow (< -500 fpm), or no symbol if less than 500 fpm rate in either direction. The traffic ground track vector protrudes from each symbol in the approximate direction of travel. Traffic Type Traffic Advisory Symbol Out-of-Range Traffic Advisory Other Traffic Table 11-1 TIS Symbology 'Own' (Client) Traffic Advisory 'Other' (Intruder) Aircraft Symbol (TA) Symbol Traffic Symbol Traffic Ground Track Vector Figure 11-2 Traffic Page Out-of-Range Traffic Advisory (TA) Symbol Figure 11-3 Out-of Range TA Symbol 11-4 GNC 420(A) Pilot's Guide and Reference 190-00140-20 Rev. K