Support
In an emergency
Do not use Five Blasts. Call on VHF Channel 16 or dial 911. Five Blasts is not a safety or navigation tool, and its information can be delayed or wrong.
Why can't I see my boat?
Five Blasts only sees vessels that broadcast AIS. Large commercial ships must carry it, but many small boats, including most small sailboats, don't. A vessel can also drop out when the public AIS feed has a gap.
What counts as an event?
A ship reporting it is aground or not under command, an AIS distress beacon, an anchor dragging, a large ship stopped in the shipping channel, two vessels passing very close, and notable ships arriving or leaving from sea. Each card shows how it was detected.
Which area does it cover?
Charleston Harbor: from the jetties and Morris Island to the Cooper and Wando rivers up to the Hugh K. Leatherman and Wando Welch terminals. North Charleston Terminal is outside the area for now.
How do I turn notifications off?
Change the event types in the app's alert settings, or turn notifications off for Five Blasts in your iPhone's Settings → Notifications.
A card looks wrong. What should I do?
Email us with the card's headline and time. False alarms are the thing we most want to fix, and reports from people on the water help.
Where does the data come from?
Public AIS vessel signals, received through AISStream. Five Blasts does not use radio or audio.