[Paddlewise] Rudder facts (was Weatherhelm)

John Winters wrote:

> Unfortunately they printed the graphs in such a small scale that taking
> information off results in lots of error not to mention the error due to
> normal distortions of copies etc. Doing the best I could for 5 degrees of
> leeway I got  a 1.8% increase in drag at 2 knots, 11.4% increase
> at 3 knots and 14% increase at 4 knots.

Thanks John. This is the kind of information I like to see.

In this rudder vs. non-rudder debate, I can't help think about a little
snippet I read in Derek Hutchinson's book on Sea Kayaking:

"A few years ago the sea kayaking world was a relatively small one, so that
if a kayak came on the market and had obvious faults the word was passed
round among paddlers by word of mouth. If the boat was a bad one, it usually
fell by the wayside and was never heard of again. This is not so today, and
the bad designs stand next to the good in the retail stores - caveat
emptor!"

I think the discussion here has centered around if rudders are bad or not. A
few have avoided this debate and looked deeper and asked "why is the rudder
needed?". The rudder is not "bad" (at least no one has presented any
evidence to show that it is) but some have offered evidence that it retards
a boats efficiency (is this bad?).

Matt Broze has repeatably stated that a rudder is not needed. To back that
up he designs boats that he stands behind not needing one. A pretty powerful
statement. Rather than trying to prove that rudders are bad, he proves (at
least to some people) that they aren't needed when the design is correct. I
like that approach.

The little blurb I quoted from John W's post above is the second piece of
information posted that shows there may be a significant increase in drag
with a rudder deployed. This doesn't mean rudders are bad, but does indicate
a paddler who needs a rudder may pay a premium for it if (s)he decides to
use it. This certainly seems to fit with what I've observed while using my
rudder (low/no drag at lower speeds, noticeable drag at higher speeds), but
my body is not calibrated enough to place a number on the amount of drag I'm
experiencing.

There are only 2 reasons I've seen to use a rudder. Someone tell me if I
missed any:

1) To compensate for a design shortfall.

2) To compensate for lack of paddler skill.

You have to empathize with those suffering from #1, and can only encourage
those suffering from #2 to get better. Some people don't know to which
category they belong (yet); something that experience will hopefully tell
them one day.

I think it would be interesting when someone asks for opinions on a certain
design in this forum, to read "that boat needs a rudder all the time - that
boat needs a rudder in high winds - that boat never needs a rudder". When
this starts to happen, as a group maybe we can again start to weed out the
bad designs.

Woody


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