TM 1-1520-218-10 3C-209 c.  TVI-920 Transponder/TCAS Display Symbols.    Symbols  displayed  on  TCAS  display  are shown in Table 3C-109. d.  TCAS Mode/Warning Flags and Messages. TCAS  mode/warning  flags  and  messages  are  shown in   Figure   3C-152   and   Table   3C-110.      They   may appear  in  one  of  the  seven  indicated  slots  on  the display face. e.  Aural  Annunciator  Messages.    There  are two  types  of  aural  annunciator  messages:  a  traffic advisory    annunciation    and    a    resolution    advisory annunciation.         The     annunciator     messages     are described in Table 3C-111. Table 3C-109.  TVI-920 Transponder/TCAS Display Symbols   SYMBOL INTERPRETATION VERTICAL SPEED DISPLAY Vertical     Speed     Scale (White) 100-ft index marks from 0 to ± 1000 fpm and 500-foot index marks from ± 1000 to ± 6000 fpm are always displayed. Pointer (White) Indicates present vertical speed.  Pointer displayed when vertical speed is valid. VERT   SPEED   X   1000 FPM (Cyan) Legend displayed on indicator when operating in the transponder only mode and in some failure modes. Red Arc(s) Do not enter range if vertical speed is outside of arc (preventive resolution); exit range if vertical speed is within arc (corrective resolution). Green Arc Recommended vertical speed to resolve corrective resolution advisory. TRAFFIC DISPLAY Aircraft (White) "Own aircraft" symbol displayed continuously. Range Ring (White) Two-mile radius range about aircraft.  If no bearing message is displayed only the forward half of ring will be displayed. Solid Square (Red) Threat-level intruder; RA generated; range and bearing relative to own aircraft. Solid Circle (Yellow) Potential threat-level intruder; TA generated; range and bearing relative to own aircraft. Solid Diamond (Cyan) Proximate traffic within ± 1200 ft and 6 nm of own aircraft. Open Diamond (Cyan) Other traffic; beyond 6 nm and/or greater than ± 1200 ft from own aircraft. Traffic altitude tag (Same color as associated symbol) Relative or absolute (flight level) altitude of intruder.  If altitude is not available, data tag is not displayed. Vert  speed  trend  arrow (Same color as associated symbol) Arrow indicating direction of vertical speed change (>500 fpm) of intruder. Partial traffic symbol (Same    color    as    fully displayed symbol) Off scale or out  of range  RA  or  TA  intruder;  symbol  at  periphery  of  display  at bearing to intruder.