The ocean is a big place.  It covers over three quarters of the planet. Your vessel can travel in open ocean for days, even weeks, without seeing another vessel, plane or anything else above the surface.

Then why is it that when you do see another vessel on the high seas, their course invariably seems to gravitate close to you?  One of life’s enduring mysteries. Lots of us ponder that question, right?

OK, maybe not.

On our most recent passage north while Carrie had the late afternoon watch, she noticed not one but two commercial vessels coming towards Brilliant from the west.  Our AIS system reported that both ships would pass close to Brilliant, each at a distance of less than 2 miles.  Carrie became understandably concerned.

As I’ve mentioned before, the AIS system provides a wealth of information about other vessels equipped with a transponder like ours. It even plots a mark on the chart plotter for the other ship’s position. Carrie verified that the two ships were traveling side by side on similar courses, and AIS told her that the CPAs (closest points of approach) would happen within minutes of one another.


Too close for comfort!

As she should have, Carrie woke me from my nap to help her address the situation.

There was still 15-20 minutes to go before CPA and with good visibility we could see both of the ships. I could visually see that the ship off our port bow was going to pass ahead of us.  A good sign.

I could also see that the second ship that was pointing straight at us off our port beam was changing course to her right, which was the proper action since we had the right of way.  Her maneuver would open up the distance of their CPA and put it behind us.  Also good.

Rechecking AIS revealed that ship number two’s CPA was now greater than 2 miles and she continued to drift visually to pass behind us.

AIS provides another very useful bit of information, the ships name. While I can’t quote the rule or law, whenever we have hailed a ship on the radio by name, they have  responded. Today was no different.

We hailed the ship passing in front of us, who acknowledged that he saw us and confirmed that he would pass well ahead of us. With the vessel passing astern of us continuing to drift left we felt the situation was now under control.

Thankfully this little encounter didn’t occur in darkness, which would have added layers of complexity.  It’s comforting to know the systems work and we use them effectively to travel safe at sea.