Chichester Yacht Club Magazine June 2018 | Page 18

Power Gives Way to Sail - by Kate Williamson,
Rear Commodore Motors
Of course it does, and of course it should. So
when a sailor sees some fool in a motor boat
get too close, or perhaps not give way in the
way they should, it’s because they don’t
have a clue.
Well… actually, perhaps not.
Other factors that
impact on a motor
boat’s ability to
manoeuvre are less
clear, but I think they break down into;
Steerage, Windage, and what I am going to
call Other Laws of Physics.
The thing is that the ColRegs say that power Steerage
gives way to sail except when their ability to
manoeuvre is constrained. Unfortunately,
In harbour there is quite properly a speed
those constraints may not all be so obvious restriction. However, a Motor Boat relies on
to everyone.
forward propulsion for steerage, and the
slower the speed, the more sluggish the
The first and most obvious constraint is the
helm is to respond. So that motor boat
draft and available depth of water. The Solar unable to keep in a straight line down the
Heritage Boat for one is very restricted by its fairway may not be an indication of how
size and ability to manoeuvre within many
much alcohol the helmsman has consumed,
parts of the harbour.
but an indication of how much trouble they
are having with their steerage at a very
low speed.
A good example of the impact low speed
can have on steerage is one my husband
noted when he was on a friend’s boat
recently.
They have a shaft drive with a rudder. At
a slow speed (as we must be in the
harbour), he could count six seconds
between the time he turned the helm for a
course correction to the time the boat
began to respond.
So the sailors among you, just think ab out
this for a moment: you are sometimes
relying on motor boaters to have
anticipated your next actions and made
the necessary course correction in
advance so that they can avoid you on a
course you have not yet committed to.
If you think about that too much, it is a
frightening thought, and no wonder
sometimes things go awry.
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