As of DataHub Firmware 4.54 and Anchor Alert 2.0, a new feature, AIS Alerts, is available.
The chartplotter on your vessel has collision avoidance and detection while the boat is moving. AIS Alerts adds collision avoidance and detection while you are at anchor, on or off the boat.
AIS Alerts creates a security zone around your boat at anchor in two ways:
Collision Zone - A radius around your vessel in meters, by default 5m. Any vessel entering this zone is assumed to be near to colliding with your vessel.
Warning Zone - A radius guard zone around your vessel in meters, by default 50m. AIS vessels moving slower than 'Speed' (default 3Kts) generate an alert when entering this zone if they are on a collision course with your vessel. Vessels travelling faster than this are assumed to be under active steering and not a risk.
What is required to use AIS Alerts
To use AIS Alerts in Anchor Alert with the DataHub, you need:
The Anchor Alert App version 2.0.4 or later.
DataHub Firmware 4.54 or later.
An Anchor Alert Pro subscription, or PredictWind Professional.
A VHF AIS receiver/transceiver connected to your boat's N2K network.
The DataHub connected to your boat's N2K network.
How to enable AIS Alerts
To enable AIS Alerts in Anchor Alert:
Connect to DataHub Wi-Fi
Open Chrome or Safari and navigate to 10.10.10.1.
Log in to DataHub.
Click Services > NMEA > AIS Alerts tab.
Tick to Enable.
Add your boat's MMSI. This step is essential to avoid false alarms from your boat.
Click SAVE & APPLY.
Open Anchor Alert and start anchor monitoring.
IMPORTANT: You only need to enable AIS Alerts in the DataHub once. Anchor Alert will only activate AIS vessel monitoring while anchor monitoring.
Anchor Alert AIS Alert Configuration Options
The following settings are available to configure for Anchor Alert AIS alerts in the DataHub:
MMSI - Add your vessel MMSI to avoid false alarms from your own AIS system.
Speed - Speed cutoff of approaching vessel in knots. Vessels travelling at this speed or faster will not generate an alert when they enter the warning zone unless they are on a course that will place them inside the collision zone.
Warning Zone - Radius of guard zone around vessel in meters. AIS vessels moving slower than 'Speed' will generate an alert when entering this zone if they are on a collision course with your vessel.
Collision Zone - Radius of circle defining the collision zone in meters. Any vessel entering this zone is assumed to be at immediate risk of colliding with your vessel.
No configuration options are required for AIS Alerts in the Anchor Alert app; however, there is a description and link to the DataHub configuration page.
Frequently Asked Questions
What Settings should I use in Anchor Alert for AIS alerts?
For most users, the default settings of Speed 3Kts, Warning Zone 50m and Collision Zone of 5m should be suitable; however, this may vary significantly depending on your vessel size (length) and how crowded the anchorage is.
Set the configuration options at anchor in the DataHub before starting anchor alert monitoring to ensure they are correct for your situation.
Does my VHF AIS need to be powered on for AIS Alerts to work?
Yes. Your VHF AIS needs to be powered on for AIS Alerts to work.
Though you may also have Over the Horizon AIS (OHA) enabled for your boat, targets received this way are not suitable for use with AIS Alerts because the Target Age (lag time from report to receipt) is in minutes, whereas VHF is real-time.
To be meaningful, AIS Alerts must be immediate.
When will AIS Alerts protect my boat?
AIS Alerts will work when your VHF AIS is powered on AND Anchor Alert is actively monitoring your anchorage.
To be detected by AIS Alerts for monitoring, the other vessel must have a VHF AIS unit which is powered on. If the other vessel has no AIS or is powered off, AIS Alerts cannot see it to monitor its position.
AIS Alerts will work on your iPhone/iPad while aboard if your boat is connected to either DataHub or boat Wi-Fi, and Anchor Alert is monitoring in the foreground or background.
To receive AIS Alerts remotely, your DataHub and iPhone/iPad must be connected to the internet.