Bob Hayes of Coral Gables, Florida, asks:
“Ive just returned from cruising in the Caribbean, and I cant say enough about my AIS. It was great to be able to see the ships around us and to use their Maritime Mobile Service Identity (MMSI) numbers to hail them on the VHF. But when we got closer to Miami on our way home we began having some close calls with foreign vessels, particularly container ships, because they would not reply to my hails on Channel 16 or 13. Arent they required by law to answer a call made to them on Channel 16?”
Gordon West replies:
These ships are required to guard Channel 16, but sometimes there are language problems. There may also be times when the VHF volume control on the bridge is turned down to keep the working area quiet.
To get their attention my first suggestion would be to put the ships AIS-derived MMSI number into your DSC (digital selective calling) radio and send them a DSC hail. You should also continue to hail them on Channel 16.
If things get tight and you fear for the safety of your boat and crew but are still unable to raise the vessel in question, select the DSC all ships alert feature and push the button. When you do, you will get the attention of every ship within a few miles. Using the name and MMSI number you see on your screen, you can then call the ship you want to talk to on Channel 16.
Even if their VHF volume is turned all the way down, the all-ships DSC call will 1) trigger their non-emergency alarm, 2) shift their VHF to Channel 16, and 3) automatically increase the ships speaker volume so the bridge personnel can hear your voice call.