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Navigation Rules essential terms made simple for all sailors

by John Jamieson on 29 Aug 2013
SWIllustration-NavRules Captain John Jamieson http://www.skippertips.com
Sail inside sheltered waters, along the coastline, or offshore and you will encounter power vessels, sailing vessels, commercial tugs and tows, and merchant ships from around the world. And yet, one of the most misunderstood parts of navigation--definitions--continues to confuse. And that alone has contributed to collisions at sea. Learn this new, simplified way of learning essential terms for safer sailing worldwide!

Navigation Rules definitions are--I believe--some of the most controversial. Time and again, you will see arguments that take one side or the other. But in my mind, the definitions will become crystal clear once you understand the logic of the rule.

Indeed, I believe this knowledge could one day help you to avoid collision with another boat or ship! Read on to discover a new way to look at the Rules and those vital definitions that will lead you to safer sailing on any body of water in the world.

How the Rules Define Your Responsibility:

Rule 2--'Responsibility'--states that your crew needs a basic knowledge of the Rules too. And that means a heck of lot more than just basic navigation lights to turn on when it gets dark. Or call the captain if you see something and don't know what to do. This applies to newbies and veterans, friends, spouse, or volunteer crew. Unless they are paying passengers, they are crew. And Rule 2 uses the specific word 'crew'.

Know These Navigation Rules 'Definitions' :

Read through these most vital 'need to know' definitions. Understand the basic definitions so that you will know how to maneuver in sight of another vessel, what lights to turn on (or turn off!) in periods of darkness or reduced visibility, and what signals to sound to maneuver with another vessel or to warn others of your location during low visibility.
Keep in mind that the Navigation Rules were written with one purpose in mind--to prevent collisions between vessels. So in my mind, it makes good 'sea-sense' to start here--at the definitions--to make the rest of the Rules so much easier to understand.

1. Power Vessels (when not using sails):

If you are being propelled --or pushed--through the water by your engine, then you are a power-driven vessel. This applies whether you have the gear in forward or reverse. Some would argue that when you have the gear in neutral, you are no longer a power-driven vessel. I believe that would be a tough argument in Admiralty court (see more on this below) because others would see exhaust water at your stern. It might be quite difficult to prove that your engine was not being used to propel you through the water.

2. Sailing Vessels:
The Rules do not mention the word 'sailboat', but they use amplification along with the word 'vessel'. A 'Sailing vessel' operates under sail alone. If she has propelling machinery fitted, it is not 'being used' (the Rules state 'being used' and make no mention as to whether the shifter has been engaged). If you have your engine on, you are no longer a sailing vessel. You are a 'Power-driven vessel'. Why?

You can bet if you were involved in a collision and another skipper saw exhaust water coming from your stern tube, he or she would have a good, solid argument that you were under power. How could you prove otherwise?

Having your engine on to charge batteries means your propelling machinery 'is being used'. Make it simple and consider that if you start your engine--bingo--you just became a 'power-driven vessel'. And you must maneuver in all of the ways the Rules require for power-driven vessels.

3. Vessel Engaged in Fishing :

Here we begin what I like to call the 'nonsense' logic you see so read on forums or discussion groups here and there. That's where folks seem to argue against what I like to call 'reality' logic--or the logic of why this particular definition was written in the first place. Indeed, some of this could most likely be the failure to read the entire sentence or paragraph.

And this one on fishing shows a perfect example of this...

If you plant a fishing pole at the stern rail and throw a line in the water, you might think you are fishing. But the Rules do not. Note the critical last three words '...which restrict maneuverability'.

In no way does a small fishing line attached to a portable pole restrict your ability to get out of the way of an oncoming ship to avoid collision. And that includes charter boats with dozens of folks casting rod and reel out for game fish. That doesn't even come close to qualifying as something that restricts the maneuverability of the charter boat to clear out of the path of an oncoming ship.

I believe it helps to always go back and think about why the Rules were written in the first place. Why go to the trouble? Those wise men gathered together from nations from all around the world had one purpose in mind. To create a universal set of Rules that if followed, would prevent collisions between vessels.

And make them simple enough that mariners of all seagoing nations on earth could follow one set of Rules in one slender, 'Reader's Digest' size book to keep their crews and vessel safe on any body of water in the world.
So in the case of having a pole out with a line in the water, how difficult would it be to get out of the way of a big ship headed your way? In a pinch, you could reel in the line or cut it if necessary. Even toss the whole rig over the side in an absolute do-or-die emergency. Sure, it would be inconvenient, but not as much so as a collision; that could ruin anyone's sailing day!

Commercial fishing vessels are a whole different story. They use heavy commercial gear weighing thousands of pounds hanging over the side or astern. Their massive commercial fishing nets will often be stretched for a half mile or more behind the vessel or beneath the sea, filled with tons upon tons of fish.

Any sailboat or power boat has an obligation to stay clear of commercial fishing vessels. And commercial fishing vessels have an obligation (as we will see later) to indicate the nature of their work with special shapes (by day) or lights (by night).

4. Vessel Not Under Command:

Lose your means of propulsion, unable to steer your boat, or howling wind and seas dismast your rigging and you fall under the status of 'Not Under Command'. Note the two key phrases that signify loss of propulsion or steerage: 'unable to maneuver' and 'unable to keep out of the way of another vessel'.

So, if you are unable to steer, sail, power, or row your way because of some exceptional circumstance (as described earlier), then other vessels described earlier need to stay clear of you.

Some sailors have asked whether this also applies to a small sailboat hove-to (lying beam to or almost beam to the seas with a reefed mainsail or trysail and a backed storm jib or no jib) in storm conditions. I believe it does not, because that vessel has a means of propulsion--her sails--in good order. In an emergency, the watch could fall off the wind and move out of the way of an approaching vessel.

On the other hand, if your sails were shredded in the same storm and your engine would not start, you would be covered under the 'not under command' status. You must indicate this to others with the proper shapes (by day) or navigation lights (by night).

5. Restricted in Ability to Manoeuver:

You may have heard the term 'RAM' that's used by sailors to describe the NavRules unique 'Restricted in the Ability to Maneuver' status. These vessels are 'restricted in the ability to maneuver from the nature of their work.

Indeed, this definition has had its 'fuzzy logic' argument that sailing vessels could be in a 'RAM' status in super light or super heavy weather. But as you will see, this just does not qualify to put you into this privileged status.

The key phrase here states 'a vessel which from the nature of her work'. Let's stop there and look at that last word...'Work'...which means just that. This would not mean sailing for recreation on a cruise or day sail or race--even in a professional capacity.

But consider that vessel like a dredge or construction barge with a crane, involved in the bridge maintenance would meet this requirement. As would an aircraft carrier launching or recovering aircraft. Or a tug involved in towing a vessel that severely restricts its ability to maneuver out of the way of another vessel.

Would the smaller Sea Tow vessels that are common in the US qualify for this status? In certain circumstances, they would. These small craft do tow large unwieldy vessels inside of narrow waterways.

In some cases, any deviation from their course could lead to grounding or the tow 'tripping'--or causing the tug to slew out of control or capsize. Any vessel that considers herself in the 'RAM' status must show the proper shapes (by day) or navigation lights (by night) for a vessel in that status.

~~~~~~~~~~~~~~~~~~~~

John Jamieson (Captain John) with 25+ years of experience shows you the no-nonsense cruising skills you need for safer sailing worldwide. Visit his website at www.skippertips.com. Sign up for the Free, highly popular weekly 'Captain John's Sailing Tip-of-the-Week'. Discover how you can gain instant access to hundreds of sailing articles, videos, and e-Books!
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