For some reason, human beings have shown a propensity for collision for as long as history has been penned (and I should throw allision* in there for good measure). The Rules of the Road were written for the days when ships came upon one another with no early warning — pre-radio and pre-radar. And even then there was the:
General Prudential Rule
ColReg 2(b) — In construing and complying with these rules, due regard shall be had to all dangers of navigation and collision, and to any special circumstances, including the limitations of the vessels involved, which may make a departure from the above rules necessary to avoid immediate danger.
The rule has remained unchanged in over a century, but the technologies helpful in reducing the need for it certainly haven’t. Radio and radar improved matters in many cases and worsened things in some. The Andrea Doria comes to mind.
In the last decade +/- we have added a new potential contributor to safety at sea — AIS — the Automated Identification System. Simply put, it uses clever VHF multiplexing to send ships’ identity and navigational information with very frequent updates to any VHF receiver in range. It provides the means to enhance situation awareness. How well those means are employed will be interesting to see as the century rolls on.
Until recently, this has left those of us who go to sea in things less than 300 gross tons unseen except by eyeballs and radar and only maybe so at that. In 2007, the Class “B” AIS transceiver was introduced, and with the general trend in electronics built cheap and sold dear, it was produced in packages mountable and powerable aboard small yachts. Some of the impetus for Class B may have come from the Government’s post 9/11 desire to prevent mass murder by small boat. Be that as it may, it is here, it costs only about twice what a really good VHF transceiver does (and that is drifting down a bit).
So we have committed to install one. Our choice of the Vesper Marine, WatchMate™ was shaped by a primary interest in a robust Closest Point/Time Approach Alarm, an uncluttered display, and low loss antenna sharing. We will mount the display below. The radar-chartplotter already has the max info on it one can safely keep sorted out under stress (perhaps a bit more actually).
While integration with the VHF radio would have been nice — to facilitate push button calling of traffic of interest — this feature/benefit is not available from this supplier. [One solution would be to replace our current VHF with one that integrates an AIS receive capability, but calling a ship by name vs digital MMSI is probably fine.]
If you want to see what the world-wide situation looks like take a look at “Live Ships Map – AIS – Vessel Traffic and Positions”