AIS target symbols

Different symbols are used to identify different types of AIS target. The symbols appearance will change to identify the target’s status.

AIS targetSymbols

Figure 1. AIS target symbols

  1. Standard vessel

  2. High speed vessel

  3. Commercial vessel

  4. Yacht

  5. Land base station

  6. Aid To Navigation (AToN)

  7. Virtual AToN

  8. Search And Rescue Transponder (SART)

AIS targetStatus

Figure 2. AIS target symbol status

  1. Dangerous target — If a target is within a specified distance CPA (Closest Point of Approach) or time TCPA (Time to Closest Point of Approach) the symbol’s outline will turn red and flash. If enabled, the Dangerous target alarm will sound when a target becomes dangerous.

  2. Uncertain target — If the target’s CPA / TCPA values are uncertain the symbols’s outline will have a dashed outline.

  3. Lost target — If data from a dangerous target is not received for 20 seconds, the symbol will be displayed with a red cross through it and flash. If enabled, the Lost target alarm will sound.

  4. AToN off position — If an AToN is off position the symbol’s outline will turn red.