Bigger On The Water, Not Only Means Bigger, But Danger As Well!
The Law Of Gross Tonnage by Wayne Spivak, National Press Corps,
United States Coast Guard Auxiliary
In a recent news release issued by the United States Coast Guard
Auxiliary, the Coast Guard and the Auxiliary wanted to educate boaters,
specifically recreational boaters about the dangers of playing in
Traffic, as defined by both the release and the federal navigation
rules are "narrow channels" that "restrict the movement of vessels,
which are constrained by their draft". Herein lies the tale of why
us small boaters should not play in traffic when the big boats are
The "Rules of the Road", which were enacted in 1980, can be viewed and/or downloaded
from the USCG at http://www.navcen.uscg.gov/?pageName=navRulesContent
or purchase it from either the US Government Printing Office or
at your local marine supplier.
Every boater should be familiar with the "Rules of the Road".
Just as you are supposed to be familiar with the vehicle and traffic
laws, you should be familiar with the nautical rules as well.
"Ignorance of the law is no excuse for breaking it..." Oliver Wendell
Holmes, The Common Law (1881).
Please note: all vessels that are 39.4 feet or larger are required
by federal law to have a copy of this book on their vessel at all
Rule number 9 – Narrow Channels, Inland states that:
"(b) A vessel of less than 20 meters [65 feet] in length
or a sailing vessel shall not impede the passage of a vessel that
can safely navigate only within a narrow channel or fairway.
The local boating public should be aware of the penalty provisions
within U.S. Code, Title 33, Section 2072, that specify "Whoever
operates a vessel in violation of the navigation rules is liable
to a civil penalty of not more than $5,000 for each violation, for
which penalty the vessel may be seized and the case shall be brought
before the district court of the United States of any district within
which the vessel may be found."
Now that the legalese has been stated, let's discuss in rational
terms why you, the recreational boater should not play in traffic.
Law of Gross Tonnage
The law, which is more common sense then explicitly written in
the code, goes like this: "The heavier vessel always has the right-of-way."
This is based on simple Newtonian physics. Newton's first law
talks about objects in motion stay in motion unless another force
is acted upon it. In other words, if a boat is moving east at 5
mph and you were in the vacuum of space, it would never stop traveling
east at 5 mph. However, we all know when we stop our engine on our
boat, we slow down.
How long it takes to go from 5 mph to zero depends on wind, and
current. Even if there was no wind or current, we'd still slow down,
because the water itself provides friction upon the hull of the
boat, and that in itself acts as a brake.
We have all observed that the bigger the object, the longer it
takes to slow down. Newton's second law of physics talks about how
the amount of force required to move an object is inversely proportional
to the mass of the object.
So, if a tug and barge were traveling down a narrow channel,
and you stopped your boat 1,000 feet away, right in front of the
tug and barge; and, if the master of the tug saw you immediately;
and if the master of the tug immediately began to stop the tug and
barge; you'd have less than one minute to move your vessel.
If you didn't move your vessel in less than 60 small seconds,
the tug and barge would just run right over you. It would be impossible
for the master of the tug to stop, based of the collective mass
of both the vessel and the barge, in 1,000 feet.
The law of gross tonnage is un-relenting. It is a fact of life.
Another fact of life is that you should not depend on the master
of the tug or any other large vessel is able to see you, either
visually or on radar.
Radar and Visual Lookouts
Radar, lookouts and even VHF radio's all work the same. They
actually work on the same basic principles of physics. Yes, physics
that subject most of us hated in high-school rears its ugly head,
Radar, and VHF Radio, as well as your ability
to see something, is all based on "line-of-sight". If it is not
in your field of vision, you won't be able to see it.
Think about it? Have you ever looked for something, but couldn't
find it, and it was right under your nose? How bout walking with
a small dog, and it disappears on you, because it is right under
your feet, but you don't see it, because you're looking further
a field, away from you.
This same principle is at work with radar, and your VHF radio.
The radar antenna on a large boat is raised much higher over the
water. This enables the ship to see farther out to sea. However,
on the downside, it also gives a larger blind area.
The radar waves generated from the antenna are narrow beams of
energy. A properly configured radar antenna won't begin to come
near the surface of the water until its maximum state range. So
a 24-mile radar will scoot high above the surface for large distances
before the waves will begin to pick-up objects that are close to
Recreational boats are close to the surface. So, even though
you may be a quarter-mile away from a large vessel, the lookout,
be it human, electronic or both, may never be able to see you.
So, to sum up today's lesson in physics. Don't play in front
of large ships. They are bigger, they are dangerous, and they may
never see you.
Oh, before I forget – never pass between a tug and its barge!
That may be the last thing you will ever do! In fact, stay as far
away from a tug and barge, or for that matter any large vessel.
Between a tug and barge you'll find a hawser (a large diameter
line or cable), which will surely decapitate the boat and its occupants,
should you collide with it. And all large vessels have large propellers,
and prop wash. The forces made by these props are enough to either
swamp your boat, drag it into the prop or combinations thereof.