AIS Target

AIS target symbols are small triangles colored by default in blue for AIS Class A and green for AIS Class B:

Note: AIS downloaded from the Internet are colored in yellow. Please refer to the AIS Online chapter for more information:

When Heading and Course Over Ground (COG) is sent by the AIS transponder, TimeZero  Professional   will use the heading information to align the AIS icon and will display a COG Vector in dashed line:

Note: The AIS COG vector length (predictor time) uses the same time parameter as your own ship setup in the Ship & Tracks Options

If the AIS target contains the vessel size information, TimeZero  Professional  will represent the shape of the vessel on the chart (in real size) when the chart is on a small range:

AIS Target Icon

AIS icon with Rate of Turn indicator. In this example, the AIS target is turning to port

AIS Lost icon. An AIS gets lost if no information updating the target location is received after a period of time. The time that causes an AIS to get lost varies with the class of AIS (A or B), its speed, and its navigation status (moored, in navigation, etc...). A lost AIS icon will disappear from the screen after 30 seconds

AIS Icon with one (or multiple) important data missing preventing CPA and TCPA computation (missing COG and/or SOG of target or Own Ship)

Dangerous AIS icon breaking an alarm condition (either CPA/TCPA or proximity alarm)

AIS Base Station icon

AIS Search and Rescue Aircraft icon

AIS SART (Personal Man Over Board transponder) icon

AIS AtoN (physical or virtual Aid to Navigation) icon

AIS Weather (AtoN with environmental sensors) icon

AIS Color

The default color of AIS targets can be changed from the Targets Options. You can choose a different color for AIS Class A or AIS Class B. You can also set the color to "variable". In this case, the target type (Cargo, Fishing, Blue Force, etc...) will be used to select the default color of the AIS icon:

You can also change the color of any AIS target individually by right clicking on its icon and selecting a color, or by adding an entry in the AIS favorite and specifying a color.

Note: When you manually change the color of a specific AIS target, TimeZero will remember this setting and will continue to represent that AIS target with the custom color even if the target is lost and reacquired or if the software is restarted. Any color that has been setup manually or defined in the AIS favorite has priority over the default color.

AIS Label

The target label can be set to display the name of the target (name of the vessel or MMSI number), the speed of the target, or a combination of both. You can select which data you want to use as target label from the Targets Options (by adjusting "Target Label"). Note that by default, TimeZero will only display a label on the selected AIS target, but if you prefer, you can display a label on all targets by selecting "Display Target Label" from the "Targets" button located on the Ribbons:

The AIS Icon and Label Text size can be adjusted from the Targets Options.

AIS Favorite

It is possible to give a Nickname and set a fixed color to one or multiple AIS from the "AIS Favorite" list located under the Targets Options. Simply open the list by clicking on the "AIS Favorite" button, click on the "Add" button, enter the MMSI number of the target, select a Nickname and color. The list can be saved (exported) for backup or to be imported on another TimeZero  Professional .

TIPS: You can also right click on an AIS icon directly on the chart and select "Favorite" to add it to the list (without having to enter its MMSI manually).

AIS Filtering

AIS targets can be filtered (automatically hidden) on the chart from the "Targets" button located on the Ribbons. You can choose to:

  • "Display all AIS": All AIS targets are displayed on the chart without any filtering

  • "Display Dangerous AIS": Only the AIS targets that are considered dangerous are displayed on the chart. AIS are considered dangerous when they fall below both CPA and TCPA values (defined in the Alarms Options), or if they are inside a radar guard zone or inside the AIS proximity alarm radius,.

  • "Apply AIS List filter on Chart": When selected, this option allows to match any filter that may be applied to the AIS list onto the chart. For example, if you select this option and decide to filter the AIS list to only display targets that are set as your favorite, only those AIS would be displayed on the chart (to match the list filter). Please refer to the Target List & Information chapter for more information on how to enable the AIS List filter.

AIS Blue Force

Some AIS receivers support a proprietary “Blue Force” mode, allowing encrypted vessels to be identified and displayed differently from standard AIS targets. When such information is available, TimeZero automatically detects Blue Force AIS targets and assigns them a specific Target Type labeled Blue Force. These targets can be visually distinguished using the AIS Variable Color settings and can be filtered separately using the list filter. The Blue Force designation is shown in the AIS target tooltip and in the AIS list (hidden by default), allowing operators to quickly identify these vessels while navigating. Blue Force targets otherwise behave like standard AIS targets in terms of display and tracking.

TimeZero sets the Blue Force target type when the NMEA0183 AIS message (VDM) includes one of the following explicit indicators provided by the AIS equipment:

  • when the NMEA 0183 talker ID for the VDM sentence is set to "EI" (example "!EIVDM") or "NM" (example "!NMVDM")

  • when the the AIS channel (normally set to A or B) is set to C or X in the VDM sentence (ex "!AIVDM,1,1,,X,...")

If any of the above indicators is present, the AIS target is automatically tagged as Blue Force in TimeZero. Users wishing to use this feature should confirm with their AIS manufacturer that at least one of these indicators is supported and enabled by the device.

Satellite AIS

Satellite AIS targets differ from standard AIS targets in that their position reports are not received directly from a local AIS receiver, but instead from a satellite‑based AIS service. Because satellite AIS messages are received at a much lower update rate, TimeZero handles these targets differently. Satellite AIS targets are identified automatically and tagged with a Satellite target type, which can be visually distinguished using the AIS Variable Color settings and can be filtered separately using the list filter. To avoid misleading position estimates, TimeZero disables target extrapolation for Satellite AIS and uses an extended timeout of up to six hours before the target disappears from the chart. Unlike regular AIS targets, Satellite AIS targets do not enter a “lost” state; they remain at their last reported position until they expire or a new update is received.

TimeZero identifies Satellite AIS targets exclusively based on the NMEA 0183 talker ID used to transmit the AIS data. When AIS messages are received using the CS talker ID (for example !CSVDM), TimeZero automatically tags the target as Satellite. Users should verify with their satellite AIS service provider that AIS data is delivered using the CS talker ID to ensure proper identification and handling in TimeZero.

AIS SART

Personal Search And Rescue Transponders (SART) use AIS messages to broadcast their position and trigger an alarm automatically in TimeZero   Professional . AIS SART can be a device on a vessel, in a life raft or a personal Man Over Board (MOB) device. In an emergency situation an alarm will be triggered and a message will appear in TimeZero asking to either center your display on the SART location or create a Go To point. The position of the AIS SART on the chart will be marked with the following icon:

TimeZero  Professional  can also receive AIS SART Test messages. In this case a simple notification will be displayed in the status bar and the icon will be displayed on your chart in green instead of red.

AIS Weather

When TimeZero detects an AIS Base Station or AIS AtoN which sends environmental data, a special weather icon is used instead of the regular Base Station or AtoN AIS icon. If the environmental data includes Wind Speed and Wind Direction, TimeZero will add a wind feather directly over the weather icon:

Note: TimeZero is compatible with the AIS Message 8 (ASM) "IMO Meteorological and Hydrographic data" DAC1 FI31, "USCG/USACE Environmental Message" DAC 367 FI 33, and "IMO Environmental Message" DAC1 FI26.

When clicking on an AIS Weather icon, a tooltip will appear with all the environmental data which is broadcasted by the station: