Dive and Discover : Expedition 3 : Daily Updates

Earlier in the cruise, I wrote about navigation and shiphandling. These are relatively simple undertakings on the high seas when a vessel is by herself and has ample sea room all around. Adding traffic (other vessels) to the mix makes the navigation/shiphandling equation a little more interesting and complex! There are thousands of ships, boats and watercraft of every description upon our seas and waterways. Somehow, they must get to where they are going without bumping into each other. Unlike driving on a road or highway, there are no double-yellow lines, traffic lights, or yield signs out on the water to regulate the flow of traffic. And, just like there are rules for driving a car in traffic, so there are rules for driving a ship or boat around other vessels.

One of the curious things about going to sea is that you can sometimes go for weeks at a time without seeing any other ships or boats. Then, suddenly, you detect another ship by radar at a range of 24 miles, and you begin tracking her (plotting her movement relative to your own). Somewhere between a range of 12 and 14 miles, you begin to see her masts poking above the horizon. At 9 miles away, you can see her hull, and it becomes clear that your courses are converging. In fact, your plot reveals that you and the other ship will be at the same place at the same time! That’s what sailors call a collision course and it needs to be avoided! What is the chance that two ships leaving different ports at different times, traveling at different speeds, and going to different destinations, will arrive at the same place at the same time in the middle of the ocean? The chance must be astronomical, but I’ve seen it happen often enough. So, how do these two ships avoid running into each other?

Fortunately, there are navigation rules that govern how ships, boats, and watercraft interact with each other. Sailors call them the Rules of the Road. The Rules are international in scope, and cover crossing, meeting and overtaking (passing) situations to name a few. The Rules also differentiate between power driven vessels, sailing vessels, and vessels of different sizes. Check out the slide show to see what the rules are when two power-driven vessels are in sight of one another, and are either meeting head on, crossing or overtaking.

Beyond the basic relationships described in the Rules of the road slide show, the Rules of the Road get very technical. For example, a power-driven vessel must stay out of the way of a sailing vessel, but a sailing vessel must not get in the way of a power-driven vessel that can safely navigate only within the confines of a narrow channel. A fishing vessel enjoys certain privileges when engaged in fishing; when not fishing, she must obey the same rules as any other power-driven vessel of her size. The Rules also define how ships interact in any condition of visibility, when in sight of one another, and when operating close to, but not in sight of, each other (as when operating in fog or rain).

Besides defining who shall give way to whom, the Rules prescribe lights to be shown and whistle and bell signals to be sounded. The positioning and color of lights on a vessel are critical to discerning the type of vessel and which way it is going at night. This determines who gives way and who holds her course. In addition, by sounding whistle or bell signals, you can let other vessels in the area know what you’re doing. In spite of their complexity, the beauty of the Rules is that, when properly applied, vessels can meet and pass each other in safety without the need to guess what the other vessel might do.

These days, most vessels carry two-way radios for communicating with each other. Using the radio to let other vessels know what you are doing or to make passing agreements with them helps us follow the Rules, and greatly improves safety on the water. This is of enormous help when all the things I have talked about -- navigation, shiphandling, and traffic -- come together on a dark, foggy night off a rocky shoreline. That is when a mariner’s knowledge and skill are put to the test.

In closing, I have an observation and a recommendation. You need a license to drive a car, and you need a license to drive a big ship. But you don’t need a license to operate a recreational boat. Whether driven by power or sail, a boat is a vehicle just like a car or ship and can be just as dangerous. Statistics show that many boating accidents occur because the Rules of the Road were ignored. Even though recreational boats do not require a licensed operator, they must still abide by the Rules. If you and your families are recreational boaters, please operate your boat responsibly and know your obligations under the Rules of the Road. Copies of the Navigation Rules are available at most any boating supplies store or from the US Government Printing Office. Further information and boating safety courses can be obtained through your local Coast Guard Auxiliary.

Throughout these essays, I have used the words vessel, ship, boat and watercraft fairly interchangeably. But did you know that each one has a specific technical definition? In nautical terms, a vessel is any object or craft that can be used for transportation upon the water. By this definition, both a log raft and a super tanker are vessels! The word boat generally refers to small craft. As a rule of thumb, sailors say a boat is any vessel that can be lifted out of the water and placed aboard a ship. These days, we use the word ship to describe any large vessel. But the original definition of ship has nothing to do with the big, power-driven vessels of today. The word ship was originally used to describe a sailing vessel that was 100% square rigged. A fine example of a ship is at the Maritime Museum in Honolulu, Hawaii. The Falls of Clyde is a four-masted tall ship that is completely square-rigged. Another beautifully restored vessel with square sails resides in Melville’s home port of San Diego. She is the Star of India and because her aftermost mast is fore-and-aft rigged, she is a bark rather than a ship.