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From: Gerald Foodman <klagjf_at_worldnet.att.net>
subject: [Paddlewise] A Rudder Experience
Date: Sat, 14 Nov 1998 21:40:53 -0800
I was on mile 10 of a 13 nautical mile paddle from Mission Bay to San Diego
Bay.  We were at a fast (for me) pace, measured afterward at 4.5 to 4.8
knots.  I was in my Solstice GTS with the rudder up trying my best to keep
up to with Kris in her Arluk IV (she is very strong).  When we rounded Pt
Loma and came in to the bay from the ocean the wind suddenly rose to about
15 knots directly abeam.  Now the GTS tracks extremely well so I left the
rudder up and was able to hold direction with no problem, except that the
occasional sweep was causing a slight strain on a not perfect rotator cuff.

I then decided to lower the rudder to ease any possible strain on my
shoulder.  As soon as the rudder was down, the stern anchored slightly and
the bow blew off.  This was easily corrected by a bit of rudder.  However I
immediately began falling behind Kris.  Added drag, I guess.  I re-raised
the rudder and caught up to her again.  I repeated the experiment with the
same results.

A bit later the wind died.  I lowered the rudder again and was able to keep
up again.

Conclusion:  The rudder adds drag only if deflected.  Obvious, I guess, if
you think about it.

Jerry

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From: Glyn Dickson <paddling_perfection_at_clear.net.nz>
subject: Re: [Paddlewise] A Rudder Experience
Date: Mon, 16 Nov 98 15:37:19 PST
Your snazzy note read......

>Now the GTS tracks extremely well so I left the
> rudder up and was able to hold direction with no problem, except 
that the
> occasional sweep was causing a slight strain on a not perfect 
rotator cuff.
> 
> I then decided to lower the rudder to ease any possible strain on 
my
> shoulder.  As soon as the rudder was down, the stern anchored 
slightly and
> the bow blew off.  This was easily corrected by a bit of rudder.  
However I
> immediately began falling behind Kris.  Added drag, I guess.  I 
re-raised
> the rudder and caught up to her again.  I repeated the experiment 
with the
> same results.
> 
> A bit later the wind died.  I lowered the rudder again and was able 
to keep
> up again.
> 
> Conclusion:  The rudder adds drag only if deflected.  Obvious, I 
guess, if
> you think about it.
> 
> Jerry
> 

Interesting observations Jerry. A conclusion we came to was that as 
a designer, you need to decide whether your kayak will be balanced 
with or without a rudder in side winds. One of our kayaks was quite 
balanced without, and then with the rudder deployed (as virtually all 
people paddle here in New Zealand) the bow would blow downwind. 
This is exacerbated by light loadings/paddlers or stern loadings. 

Consequently we now produce boats that weathercock without the 
rudder, but are balanced (or more balanced depending on the final 
tradeoff we choose) with the the rudder. The stronger the winds, the 
more of a problem it becomes, and we do live in a very windy part of 
the world here.

I concur that using a rudder to turn, or hold trim causes drag. 
Paddling an Olympic K1 with a speedo mounted shows it clearly. 
Small steering movements show an instant speed loss, even with the 
tiny K1 rudder. Major turns show a massive speed loss. A sea kayak 
rudder which is most often a pretty large and crude foil will show big 
losses as its angle of attack increases.

For all that however, we've found that for our paddling conditions, 
rudders are more energy efficient overall both in racing and touring. 
The extra effort used to sweep stroke or lean the kayak to turn can 
be put into paddling instead. There are definitely some conditions 
where the rudderless kayak is faster however.

I also found that during speed testing of our latest boat, not deploying 
the rudder gave me an extra 0.3 of a knot (7.3 rather than 7.0) 
sprinting, but at a steady 5 knots I couldn't detect the difference. Of 
course that was in flat water, and I wasn't using the rudder to turn 
unless inadvertently, so the drag does become considerable at speed 
even without deflection.

Cheers,

Glyn Dickson
Paddling Perfection New Zealand
Finest Quality Handcrafted Kayaks
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From: John Winters <735769_at_ican.net>
subject: Re: [Paddlewise] A Rudder Experience
Date: Sat, 14 Nov 1998 21:51:53 -0500
Gerald wrote;


>I then decided to lower the rudder to ease any possible strain on my
>shoulder.  As soon as the rudder was down, the stern anchored slightly and
>the bow blew off.  This was easily corrected by a bit of rudder.  However
I
>immediately began falling behind Kris.  Added drag, I guess.  I re-raised
>the rudder and caught up to her again.  I repeated the experiment with the
>same results.
>
>A bit later the wind died.  I lowered the rudder again and was able to
keep
>up again.
>
>Conclusion:  The rudder adds drag only if deflected.  Obvious, I guess, if
>you think about it.

The rudder adds drag even when not deflected (surface friction plus some
form and wave making drag)  but the dramatic difference you noticed may
have been due to stall. Stall occurs most easily in flat plate rudders that
are common on sea kayaks. You may have been getting stall even with the
rudder aligned fore and aft due to the leeway being made by the boat.

Nicely shaped commercially available rudders see to be the exception rather
than the rule here  here in North America. The "Classic" configuration for
a rudder would be the NACA 0006 airfoil. Its characteristics would be a
thickness of 6% of c (c = the airfoil chord), maximum thickness 30% of c
from the leading edge and a leading edge radius of 0.04% of the c.



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From: <rdiaz_at_ix.netcom.com>
subject: Re: [Paddlewise] A Rudder Experience
Date: Mon, 16 Nov 1998 10:36:57 -0800
John Winters wrote:
> 
> Gerald wrote;
> 
> >I then decided to lower the rudder to ease any possible strain on my
> >shoulder.  As soon as the rudder was down, the stern anchored slightly and
> >the bow blew off.  
> 
> The rudder adds drag even when not deflected (surface friction plus some
> form and wave making drag)  but the dramatic difference you noticed may
> have been due to stall. Stall occurs most easily in flat plate rudders that
> are common on sea kayaks. You may have been getting stall even with the
> rudder aligned fore and aft due to the leeway being made by the boat.
> 
> Nicely shaped commercially available rudders see to be the exception rather
> than the rule here  here in North America. The "Classic" configuration for
> a rudder would be the NACA 0006 airfoil. Its characteristics would be a
> thickness of 6% of c (c = the airfoil chord), maximum thickness 30% of c
> from the leading edge and a leading edge radius of 0.04% of the c.

You also may want to look into what is termed a "balanced" rudder. 
However, its primary use is in sailing kayaks, so I have no idea how
well it will work for a paddled kayak.  Basically it is one in which 20%
of the blade is forward of the pivot point of the rudder.  On most
rudders the pivot is at the lead edge of the blade so that zero percent
is forward of this.  The balanced rudder swings out differently when
being used and seems to need less radical thrusting sideways to achieve
the same amount of turn.

I know it has been used to replace the standard rudder that comes with
Kleppers, which are not all that deep in the water and have a rather
horizonal thrust to them, i.e. they are big and shallow rather than
being small and deep.  Mark Ekchart at the Klepper Service Center makes
one as part of his after market business, Long Haul Products Inc.  It
can be replicated cheaply using the standard Klepper rudder.  One knocks
out the rivet that holds the blade in its bracket, then reverses the
blade and re-attaches it to the bracket.  The result is a rudder that
looks acts like a balanced rudder (with about 15% of its blade forward
of the pivot point) and runs deeper in the water than the blade in its
factory setup.  I had a description of it in my newsletter which I would
be glad to fax or mail to anyone who asks.

Again, what I say may not apply to paddling but it works wonders in
sailing a kayak.  The original idea of using a balanced rudder comes
from Mark Balogh of Balogh Sail Designs.  The idea of reversing the
standard Klepper rudder comes from Dieter Stiller who was the North
American distributor for Klepper.  It was something he would hesitate to
tell people since he felt everything about Kleppers was pretty perfect. 
But I managed to wrangle it out of him one day in a friendly teasing
exchange.  The solution is so simple with the standard Klepper rudder
that it should be picked up by just about any Klepper owner to get less
stall out of their rudder.

ralph diaz


-- 
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"Where's your sea kayak?"----"It's in the bag."
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From: Alex Ferguson <a.ferguson_at_chem.canterbury.ac.nz>
subject: Re: [Paddlewise] A Rudder Experience
Date: Tue, 17 Nov 1998 09:17:40 +0000
[RD]

> I know it has been used to replace the standard rudder
> that comes with Kleppers, which are not all that deep in
> the water and have a rather horizontal thrust to them,
> i.e. they are big and shallow rather than being small and
> deep. 

If you are referring to the balanced rudder fitted later versus 
the original rudder fitted to a Klepper, then it is nothing to 
do with the balance. Replacing the "barn-door" of a blade 
with a long narrow blade makes an enormous difference to 
the rudder performance - I know, I've done it.  

> and runs deeper in the water than the blade in its
> factory setup.

The crucial point. I fitted one of my standard Data General 
front panel blades (not one of my commercial production 
blades).

> It was something he would hesitate to
> tell people since he felt everything about Kleppers was pretty perfect.

For paddling in a very shallow river maybe (original 
rudder).

I also fitted decent rudder pedals in the afore mentioned 
Klepper.

Alex
--
----------------------------------------------------
Alex Ferguson      a.ferguson_at_chem.canterbury.ac.nz
Electronics Workshop, Chem Dept, Univ of Canterbury
Christchurch, New Zealand
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From: <rdiaz_at_ix.netcom.com>
subject: Re: [Paddlewise] A Rudder Experience
Date: Tue, 17 Nov 1998 07:45:14 -0800
John Winters wrote:
> 
> Ralph wrote;
> 
> (SNIP)
> 
> >You also may want to look into what is termed a "balanced" rudder.
> (SNIP)
> 
> I know of no reason why balancing a rudder would reduce stall. Balancing
> the rudder reduces the torque on the rudder assembly and consequently the
> load on the system hardware. If it appears the rudder functions better that
> way one might look for some other reason. For instance, changing the
> underwater shape may have altered the hydrodynamic sweep of the blade. This
> could also be achieved with an unbalanced rudder.
> 
> For a sailing boat the balanced rudder might be more important because the
> boat will make greater leeway and the rudder loading will be higher
> although given the small rigs of sailing kayaks it still does not appear to
> me as a big deal. Sailing dinghies like the Flying Dutchman, 505, Finn etc
> use conventional rudders with no balance without problems so I would wonder
> why a sailing kayak might need one.

Perhaps you are right and it acts as a placebo for those kayak sailors
using one.  But to a man, they report great results from using one. 
This goes for those with years of experience and for relatively new
kayak sailors.

When it first started getting used down in the kayak sailing
get-together in Cedar Island, North Carolina in 1992, one of these
sailors said it was like having an overdrive gear.  Again, maybe it is a
placebo.  I haven't tried making the old switcheroo to see if they feel
any different.


ALSO
Alex Ferguson wrote:
> 
> [RD]
> 
> > I know it has been used to replace the standard rudder
> > that comes with Kleppers, which are not all that deep in
> > the water and have a rather horizontal thrust to them,
> > i.e. they are big and shallow rather than being small and
> > deep.
> 
> If you are referring to the balanced rudder fitted later versus
> the original rudder fitted to a Klepper, then it is nothing to
> do with the balance. Replacing the "barn-door" of a blade
> with a long narrow blade makes an enormous difference to
> the rudder performance - I know, I've done it.

Actually, yes and no.  The results with the balanced rudder started with
guys sailing hardshell kayaks down there.  The quote about overdrive
above was from someone using both a single and double Easy Rider.

The Klepper barn door rudder switchers also reported the same.
> 
> > and runs deeper in the water than the blade in its
> > factory setup.
 
> > It was something he would hesitate to
> > tell people since he felt everything about Kleppers was pretty perfect.
> 
> For paddling in a very shallow river maybe (original
> rudder).

Very shallow water :-)

best,

ralph diaz

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-----------------------------------------------------------------------
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"Where's your sea kayak?"----"It's in the bag."
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From: John Winters <735769_at_ican.net>
subject: Re: [Paddlewise] A Rudder Experience
Date: Sun, 15 Nov 1998 12:57:55 -0500
Ralph wrote;


(SNIP)

>You also may want to look into what is termed a "balanced" rudder.
>However, its primary use is in sailing kayaks, so I have no idea how
>well it will work for a paddled kayak.  Basically it is one in which 20%
>of the blade is forward of the pivot point of the rudder.  On most
>rudders the pivot is at the lead edge of the blade so that zero percent
>is forward of this.  The balanced rudder swings out differently when
>being used and seems to need less radical thrusting sideways to achieve
>the same amount of turn.
>
(SNIP)

I know of no reason why balancing a rudder would reduce stall. Balancing
the rudder reduces the torque on the rudder assembly and consequently the
load on the system hardware. If it appears the rudder functions better that
way one might look for some other reason. For instance, changing the
underwater shape may have altered the hydrodynamic sweep of the blade. This
could also be achieved with an unbalanced rudder.

For a sailing boat the balanced rudder might be more important because the
boat will make greater leeway and the rudder loading will be higher
although given the small rigs of sailing kayaks it still does not appear to
me as a big deal. Sailing dinghies like the Flying Dutchman, 505, Finn etc
use conventional rudders with no balance without problems so I would wonder
why a sailing kayak might need one.

Cheers,
John Winters
Redwing Designs
Specialists in Human Powered Watercraft
http://home.ican.net/~735769/

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From: John Winters <735769_at_ican.net>
subject: Re: [Paddlewise] A Rudder Experience
Date: Mon, 16 Nov 1998 07:36:37 -0500
Alex wrote;
(SNIP)

>If you are referring to the balanced rudder fitted later versus
>the original rudder fitted to a Klepper, then it is nothing to
>do with the balance. Replacing the "barn-door" of a blade
>with a long narrow blade makes an enormous difference to
>the rudder performance - I know, I've done it.

To elaborate on Alex's comments.

The reason for deeper rudders (all else being equal) being more functional
lies in their being below the separated flow at the stern. At the stern and
sometimes even further forward on some boats the flow may be moving in the
same direction as the boat. This, of course, is the flow one benefits from
when wake riding and if you can hold you bow right up close to the stern
you get a nifty free ride. In my much stupider youth I once tried to ride
the wake of a barge tow. Great fun but great stupidity. We were sucked
along so fast we actually made headway directly into the wind with the
sails luffing. All went well until we realised we were being drawn ever
closer to the stern of the barge. Talk about panic. Just barely escaped. I
was still shaking when we finished the race.

An interesting phenomenon can sometimes occur when the boat can actually
turn in the opposite direction to that intended because of this reversed
flow. I experienced this once when sailing an owner designed  IOR rule
beater with an oddly shaped stern. Very scary business with the spinnaker
up. It was the last boat he designed for himself. ;-)

As an aside, you may recall Nick's comments on the Inuit kayak speeds. If
you have ever tucked yourself in behind a larger sailboat and been sucked
right along you will appreciate the effect on a smaller boat. It is quite
an easy thing for a small light boat to keep up with a larger ship so long
as one stays in the proper area of the wake. It pays not to accept
conclusions from observations until one knows all of the circumstances.

But I digress.

Of course, rudders, and especially high aspect ratio rudders, work even
better when properly shaped. The proper section shape has even greater
importance when the rudder is surface piercing because there is no end
plate effect and the aspect ratio suffers. The rudder also will have a
greater tendency towards ventilation.

(SNIP)

>The crucial point. I fitted one of my standard Data General
>front panel blades (not one of my commercial production
>blades).

Not sure what this rudder looks like and would be interested in a
description of it.

Cheers,
John Winters
Redwing Designs
Specialists in Human Powered Watercraft
http://home.ican.net/~735769/



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From: Roger Korn <rkorn_at_europa.com>
subject: Re: [Paddlewise] A Rudder Experience
Date: Tue, 17 Nov 1998 06:56:13 -0800
John Winters wrote:

> <snip>... In my much stupider youth I once tried to ride
> the wake of a barge tow. Great fun but great stupidity. We were sucked
> along so fast we actually made headway directly into the wind with the
> sails luffing. All went well until we realised we were being drawn ever
> closer to the stern of the barge. Talk about panic. Just barely escaped. I
> was still shaking when we finished the race.

<snip>
This works very well here on the Columbia River with log boom tows. The surface
water moves fairly rapidly forward until you are about 10 feet behind the log
boom, then slows to zero speed with respect to the logs. The kayak gently
nudges the logs and sits there while you eat lunch, have a beer, whatever. The
deeper circulation behind a laden barge, however, produces a violent sheer in
the vertical plane just behind the barge. I don't want to try that out, because
I don't know where I'd be swept in the event of a capsize.

Roger

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From: Alex Ferguson <a.ferguson_at_chem.canterbury.ac.nz>
subject: Re: [Paddlewise] A Rudder Experience
Date: Wed, 18 Nov 1998 09:00:29 +0000
[AMF] 
> >The crucial point. I fitted one of my standard Data General
> >front panel blades (not one of my commercial production
> >blades).
[JW]
> Not sure what this rudder looks like and would be interested in a
> description of it.

19" x 4" piece of aluminium with the sharp corners knocked 
off. The only HiTech bit being its origin :-) Originally from  
Data General Eclipses or Nova computers (19" rack mount). 
Just so much better getting some blade deeper into the water 
at a better aspect ratio. I usually do have a little bit of 
balance because the lower end is just forward of the hinge 
line. Because the blade goes deeper before lifting when the 
tip hits something, my stanmdard production lifting/tilting 
rudder assembly is better. I also shape the blades a bit better 
though a foil is the proper way to go.

Alex
--
----------------------------------------------------
Alex Ferguson      a.ferguson_at_chem.canterbury.ac.nz
Electronics Workshop, Chem Dept, Univ of Canterbury
Christchurch, New Zealand
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From: <SGScorpio_at_aol.com>
subject: Re: [Paddlewise] A Rudder Experience
Date: Tue, 17 Nov 1998 11:52:27 EST
In a message dated 11/17/98 7:00:22 AM Pacific Standard Time, rkorn_at_europa.com
writes:

<< 
 <snip>
 This works very well here on the Columbia River with log boom tows. The
surface
 water moves fairly rapidly forward until you are about 10 feet behind the log
 boom, then slows to zero speed with respect to the logs. The kayak gently
 nudges the logs and sits there while you eat lunch, have a beer, whatever.
The
 deeper circulation behind a laden barge, however, produces a violent sheer in
 the vertical plane just behind the barge. I don't want to try that out,
because
 I don't know where I'd be swept in the event of a capsize.
 
 Roger
 
 ***************************************************************************
  
Roger,

SHAME on you drinking BEER when you are in the cockpit!!!! 

You need to be lashed to the rudderpost and have TWENTY lashes with a wet pair
of booties!!!!!  ;)

sg

 
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From: Roger Korn <rkorn_at_europa.com>
subject: Re: [Paddlewise] A Rudder Experience
Date: Tue, 17 Nov 1998 12:13:08 -0800
Hi Steve,

I am speaking from former experience. I never "hit bottom" with alcohol, but last
year I got close enough to see it and didn't like the view, so I've been sober
since last December 13 and feeling much better about life in general. "Ol' Blue"
(the Sealution I bought from you two years ago at the fall sale) is doing fine. I
go places with that boat that I would never touch in one of my lightweight, high
speed tortured ply boats - into the rocks at Cape Falcon, up onto the rough
shingle of Vancouver Island.

Have a great year!

Roger

SGScorpio_at_aol.com wrote:

> In a message dated 11/17/98 7:00:22 AM Pacific Standard Time, rkorn_at_europa.com
> writes:
>
> <<
>  <snip>
>  This works very well here on the Columbia River with log boom tows. The
> surface
>  water moves fairly rapidly forward until you are about 10 feet behind the log
>  boom, then slows to zero speed with respect to the logs. The kayak gently
>  nudges the logs and sits there while you eat lunch, have a beer, whatever.
> The
>  deeper circulation behind a laden barge, however, produces a violent sheer in
>  the vertical plane just behind the barge. I don't want to try that out,
> because
>  I don't know where I'd be swept in the event of a capsize.
>
>  Roger
>
>  ***************************************************************************
>
> Roger,
>
> SHAME on you drinking BEER when you are in the cockpit!!!!
>
> You need to be lashed to the rudderpost and have TWENTY lashes with a wet pair
> of booties!!!!!  ;)
>
> sg
>



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From: Nick Schade <schade_at_guillemot-kayaks.com>
subject: Re: [Paddlewise] A Rudder Experience
Date: Wed, 18 Nov 1998 22:23:15 -0500
At 11:52 AM -0500 11/17/98, SGScorpio_at_aol.com wrote:

>
>SHAME on you drinking BEER when you are in the cockpit!!!!
>

Do you expect him to sit in the front hatch to the drink beer? Where else
in a kayak should you drink. Seems like the chances of spilling would be
increase by moving out of the cockpit.



Nick Schade
Guillemot Kayaks
10 Ash Swamp Rd
Glastonbury, CT 06033
(860) 659-8847

Schade_at_guillemot-kayaks.com
http://www.guillemot-kayaks.com/

>>>>"It's not just Art, It's a Craft!"<<<<


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From: John Winters <735769_at_ican.net>
subject: Re: [Paddlewise] A Rudder Experience
Date: Tue, 17 Nov 1998 07:06:32 -0500
Ralph wrote;

(SNIP)

>
>Perhaps you are right and it acts as a placebo for those kayak sailors
>using one.  But to a man, they report great results from using one.
>This goes for those with years of experience and for relatively new
>kayak sailors.

Before I went out on a limb and calimed a placebo effect I would like to
try one and flip flop from one to the other to see what happened. So many
things can have an effect. For instance a rudder that flops around rarely
feels as "good" or effective as one that is more rigid. Fortunately this
rudder business has been studied to death by the sailing types.  Even so a
bit of disagreement exists. Some swear by skeg mounted rudders and some
swear at skeg mounted rudders. At least they agree on most of the general
principles of foil shape, aspect ratio etc.

I suppose trying out more rudders should go on the project list for next
year.

(SNIP)

Even though I fall into the anti rudder camp I believe that rudders could
be better designed and built. And, as a consequence, more useful and more
effective.  I sailed a canoe a week or so ago built by a guy who has been
sailing canoes for many, many years. It also had a low aspect ratio flat
plate aluminium rudder. The rudder flopped around and felt mushy. I found
it difficult to evaluate the boat when I could hardly feel anything through
the rudder.

I think rudders get a bad name because most have such poor shapes and
rigging. Who knows, a really good rudder my convert me :-)

Cheers,
John Winters
Redwing Designs
Specialists in Human Powered Watercraft
http://home.ican.net/~735769/





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From: Gerald Foodman <klagjf_at_worldnet.att.net>
subject: Re: [Paddlewise] A Rudder Experience
Date: Thu, 19 Nov 1998 21:05:41 -0800
>
 A conclusion we came to was that as
>a designer, you need to decide whether your kayak will be balanced
>with or without a rudder in side winds. One of our kayaks was quite
>balanced without, and then with the rudder deployed (as virtually all
>people paddle here in New Zealand) the bow would blow downwind.
>This is exacerbated by light loadings/paddlers or stern loadings.
>
>Consequently we now produce boats that weathercock without the
>rudder, but are balanced (or more balanced depending on the final
>tradeoff we choose) with the the rudder. The stronger the winds, the
>more of a problem it becomes, and we do live in a very windy part of
>the world here.
>


Glyn,

Do you think many designers actually choose whether to balance the hull
design to be neutral with the rudder deployed, rather than with it up?  How
would you do that anyway?  Wouldn't small variations of the load
distribution change the result.

I prefer paddling my Solstice GTS without its rudder deployed.  It is only
under certain conditions of wind and chop that the rudder is a real benefit.
I think that I am happy with the balance of the GTS with the rudder up, and
am willing to pay the penalty of having the  bow blow off a bit in a side
wind.

Jerry

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From: John Winters <735769_at_ican.net>
subject: Re: [Paddlewise] A Rudder Experience
Date: Thu, 19 Nov 1998 06:47:12 -0500
Gerald wrote;

>
>Do you think many designers actually choose whether to balance the hull
>design to be neutral with the rudder deployed, rather than with it up?
How
>would you do that anyway?  Wouldn't small variations of the load
>distribution change the result.

I cannot speak for other designers but I calculate the stability roots
using a formula I devised for canoe design about eight years ago. Since
canoes don't use rudders getting it right is pretty important. Having said
that, I should point out that stability roots seem to be most useful from a
relative standpoint and one has to have a design that tracks well as a
starting point for comparison. Failing that, having access to a tank with a
rotary arm can be useful.

>I prefer paddling my Solstice GTS without its rudder deployed.  It is only
>under certain conditions of wind and chop that the rudder is a real
benefit.
>I think that I am happy with the balance of the GTS with the rudder up,
and
>am willing to pay the penalty of having the  bow blow off a bit in a side
>wind.

As I think I mentioned in another post, reducing the area of the rudder
will probably cure the lee helm problem and giving it an airfoil shape will
make it work better anyway.

Cheers,
John Winters
Redwing Designs
Specialists in Human Powered Watercraft
http://home.ican.net/~735769/

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From: Bob Denton <BDenton_at_aquagulf.com>
subject: RE: [Paddlewise] A Rudder Experience
Date: Fri, 20 Nov 1998 09:42:49 -0500
There's an interesting article by Frank Goodman (Designer of the Nordkapp)
in the 1st or 2nd edition of Ocean Paddler. He discusses the issues of
weather cocking and the effect that forward motion has on the boat in cross
winds and waves.

Cya 

Bob Denton
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