"Why,"
the rational individual is likely to ask, "would anyone want
to put a sail on an open canoe?" Sure, it had been done before;
even successfully, for that matter. But with all of the sophisticated,
well-designed sailboats available, why would anyone even consider
such an unlikely, Rube-Goldberg-like contraption? Probably because--like
Mt. Everest--it was there. Well, half of it was there, anyway.
The canoe was sitting in the yard, taking up space and killing
the grass. Only the sail was lacking.
If one is dead set on sailing a canoe, about the only
way to salvage any self-respect in the process is to sail it fast.
Beat the competition, and they stop laughing at you. At least in
public. And while I cannot "beat the competition" with
any consistency, when conditions are right, I have been able to
hold my own against a Capri 14, an O'Day 19, a Picnic Cat, a SeaPearl
tri, and any number of small, off-brand dinghies. This was achieved
after a six year tweaking process, using some $50 worth of assorted
plywood, scrap lumber and hardware. And using sails that were homemade,
or pulled out of trash, or given to me by neighbors. Sailing faster
has involved improving the state of my technology, surely, but perhaps
as importantly, the state of my knowledge. "Getting up to speed,"
refers to my learning curve as much as anything.
My first canoe rig was a sail of 42 square feet, cut from an acrylic
tent fly. See
Diagram Loosely termed a lateen, it featured
a short, two-legged mast, and a yard that didn't swivel, but was
fixed in place. I steered using a canoe paddle, a measure that trapped
me near the stern, since helming from a forward position doesn't
yield the necessary leverage. Two high-aspect leeboards completed
the original equipment. Since both were deployed at the same time
and all the time, the "leeboards" label is not quite accurate.
Eventually, I added a light-weight, somewhat flexible sprit boom-more
like a full length batten, really- to the mix. This helped to extend
the sail more completely on a broad reach or on a run.
On a broad reach, my speed was quite impressive, but
only when I dismantled the leeboards and sailed without them. On
other points of sail, however, my performance was deficient; particularly
when I was in shallow water and my boards got stuck in the mud.
Hard to win races when you're stuck in the mud. Doesn't do much
to advance the self-respect agenda, either.
Tinkering with the leeboard design proved very productive. I made
three changes in fairly rapid order. I moved them aft to improve
helm balance. I shortened them, while at the same time increasing
their surface area. And I made them self-activating or self-tending;
such that whenever I changed tacks, the leeward board would drop
into position, while the windward one would be lifted clear of the
water. The effect of these improvements was dramatic; all served
to reduce drag or water resistance. The canoe acted like she had
more energy; almost as if she was sleeping better nights. Plus,
I got stuck in the mud less frequently.
Adding a rudder proved even more productive, speed-wise.
Intended to make my sailing experience easier and more convenient,
the rudder, surprisingly, stepped up my performance as well. Mostly
for unexpected reasons. A more-than-complete description of my unorthodox
canoe rudder appeared in SCA #10. If you missed it there, the article
is posted on my web site. In brief, my rudder consists of two small
fins joined by a cross-member that pivots on a bolt that passes
through the canoe's stern deck. Shock cords run forward from each
fin and are fastened amidship. Pull or stretch the starboard shock
cord and the canoe turns to starboard; port shock cord to turn to
port. Release pressure on the shock cords, and you sail straight.
You can maintain your course, in other words, without touching your
steering mechanism. And you can change course while sitting anywhere
in the after half of the boat. 
A number of advantages accrue. First and most obviously,
this leaves a hand free for bailing; an activity often in demand
in an any open boat. Second, with the helmsman no longer trapped
in the stern, his body weight can be moved to where it best aids
stability. And with stability comes speed. I could now sit amidships,
where the canoe=s beam is at the max and where my weight, therefore,
is on the longest possible lever arm. Third, my canoe had become
self-steering to a certain extent. When a gust hits, the canoe responds
by turning slightly into the wind. The leading edge of the sail
luffs, and excess wind is shed. Once the gust passes, the canoe
falls off and resumes its original course. The sequence occurs automatically;
without any intervention on my part.
Fourth, a boat that is self-steering almost always
exhibits good helm balance, which, in turn, is directly related
to speed. By definition, the well-balanced boat creates less drag.
Every time you push the tiller off the boat's centerline, you create
drag; "rudder deflection drag," to use the technical terminology.
The better balanced the boat, the less you have to adust the tiller.
The less you manipulate the tiller, the faster you can travel.
Good helm balance facilitates speed indirectly as
well; it then becomes possible alter course by shifting body mass.
Move forward or leeward, and the balanced boat points higher; move
aft or windward and the boat turns downwind; all with no rudder
deflection drag whatsoever. Steering-through-weight-shifting now
became possible for me.
Fifth, when a small boat's pitching becomes violent,
forward progress can come to a standstill. Pitching represents a
double whammy; it robs the boat of momentum and it ruins the smooth
airflow around the sail. I can reduce the canoe=s pitching somewhat,
by relocating further forward. Something I could not do when relying
a paddle for a rudder.
Not that the new rudder was perfect, by any means.
It still had its problems. The fins were too small, so the stern
was always being pushed about by both wind and wave. The leading
edges were vertical and accumulated seaweed readily. Further, once
I reached about 4 knots, the rudder fins would ventilate. Air would
travel down the fins, especially along their windward surfaces.
Essentially, half of each fin was operating in air rather than water.
Not exactly a prescription for efficiency.
The remedy to these problems was pretty obvious. But for the time
being, they were problems I could live with. If I were racing, and
my self respect were on the line, it would be a different matter.
But that didn't come up until later.
It=s worth noting that all speed gains to this point
were realized by adding and modifying foils; no changes had yet
been made to either the sail or hull.
A new pair of canoe seats that incorporated a mast
step in each, allowed for a whole new set of options. (The construction
of these seats was described in SCA #19. The article also appears
elsewhere on the website.) Masts and rigs could now be freely interchanged,
opening up a whole new range of experimental possibilities.
The first new rig to receive a test was a standing
lug. (Diagram 2.) I cut it
from the mainsail of some obscure daysailor. The lug was about the
same overall height as my original lateen, but was 35% larger in
area. In theory, the lug rig has much to recommend it: a low center
of effort, a capacity to maximize sail area on short spars. Unfortunately,
one can't sail theory. For me, the lug did not produce: speed seemed
to be no better; pointing ability, meanwhile, got noticeably worse.
Bad helm balance was probably the major part of the problem. Easy
enough to fix, it just didn't seem worth the effort. Chalk it up
to experience and move on, as we at the forefront of science say.
Diagrams
The next test rig was cannibalized 5.3 square meter
windsurfer sail along with its carbon fiber mast. There are a couple
of problems using a windsurfer sail "as is." The mast
is too tall for an empty canoe. To keep from capsizing just from
the weight of the rig, either the mast must be stepped while you
stand or kneel in the boat. Or you have to hold the whole thing
upright with one hand and step the mast with the other, until you're
ready to clamber aboard. On top of that, the standard wishbone boom
is heavy; much heavier than a single-legged spar of equal length.
Trouble is, it's not so easy to simply discard the
standard issue boom. A windsurfer sail relies mightily on its wishbone
boom to maintain its proper shape. The mast is supposed to be "loaded"
so that it describes a curve. And it is the wishbone boom that does
the loading. Get rid of the boom, and the sail no longer takes the
right shape.
My solution to these dilemmas was to modify the sail's
cut, and to use it as a lateen. (Diagram
3.) This allowed me to hoist the sail from inside the canoe.
What had been a mast became a yard that pivoted about a short, wooden
mast. In order to accommodate the sail for use with a straight spar
rather than a curved one, I installed a series of grommets along
the sail's luff, gathered up the excess fabric, and lashed it-or
maybe "brailed" is the proper term-to the mast-cum-yard.
The end product was tall rig, a sail of very high aspect ratio,
but of smaller area than my original lateen. I used one of four
possible batten pockets, installing a full-length batten about one-third
of the way down. I sailed without a boom.
Off the wind, this sail seemed to achieve the same
speed as my initial 42-square-footer. But on the wind it was noticeably
better; I could point higher and come about much more handily. I
was also pleasantly surprised to find that tall as the new rig was,
I felt no more threatened in strong breezes. Stability seemed to
have suffered not at all.
After six months or so of using the windsurfer sail
as a lateen, it belatedly occurred to me to convert to a Gunter
rig. This involved simply lashing the heel of the yard to the base
of the mast. The yard, therefore, no longer swung about the mast.
Instead, it was held fully erect. As a result of this simple modification ,
weatherliness improved even more. And it only took a mere six months
for the idea to implant itself. Good thing I'm not on a schedule.
(The photo shows the canoe rigged with her 39 sf windsurfer sail
in the Gunter mode.)
About that same time, a second epiphany occurred:
I realized that if I consciously heeled the canoe over when coming
about, the canoe changed tacks much more smartly. It should have
been obvious long ago: If a canoe has a straight, unrockered keel,
it will want to travel in a straight line. It won't like to make
turns. But heel it over onto its curved side and a canoe will twirl
on a dime. Now, none of this comes as news to paddlers of kayaks
or canoes. Their first lesson in paddling probably included instruction
on the proper and easy way to change course; namely, list over onto
your side. Sailors of canoes, on the other hand, lacking the formal
education, find it necessary to rediscover the wheel. Good thing
I'm not on a schedule.
It was at this juncture in my evolution, that neighborhood
sailors decided to hold weekly races. Suddenly, the pressure was
on. The impending races and their implications for my self-respect
prompted me to make the changes that I knew were essential: an improved
rudder and a larger sail.
The new sail was also began its life as a windsurfer
sail. In this instance, however, I cut off all the excess material.
I also made a deliberate attempt to introduce curvature into the
sail; a 10% camber, which is considered ideal. New grommets, installed
along the sail's luff, were located to produce the desired camber.
Plastic cable ties were the "mast hoops" that held the
sail to the mast. To create a boom or batten pocket, I rolled up
fabric at the foot of the sail and added rivets to keep in place.
A length of half-inch CPVC plumbing slid into the pocket and served
as a lightweight, flexible boom. Probably a bit too flexible for
optimal performance, but certainly better than nothing, particularly
on downwind legs.
I cut new rudder fins from three-eights plywood, increasing
their size in the fore-and-aft dimension, but not their draft. I
also created a knob or an elbow in their leading edges, as can be
seen in the accompanying photograph. This measure, I hoped, would
reduce the ventilating that occurred with the earlier version. In
addition, I hoped that seaweed would no longer be trapped along
the lower two-thirds of the fins, where they now tapered aft. Both
hopes panned out in practice. My rudder deficiencies were cured.
I was now race ready. Or so I thought.
Turns out, I wasn't very competitive in a lot of circumstances.
I sustained a number of last place finishes, though never by a humiliating
margin. On the other hand, when racing conditions were ideal for
me,I was able to finish in the middle of the pack. Not fast enough
for bragging rights, maybe, but still respectable.
Why wasn't I able to rack up a better racing record?
I still have an open boat, remember, that starts to take water over
the sides once the waves reach a foot-and-a-half in height. Or if
it heels more than fifteen degrees. No real margin for error there.
Also, with a narrow beam and no means of hiking out, my stability
is limited. My sails are either homemade or home-modified. In either
case, a professional sailmaker would find my efforts laughable.
The new, enlarged Gunter rig is definitely better in light airs.
But it's still not large enough to be truly competitive when wind
speed is less than five knots; then boats with taller rigs and higher
sail-area-to-displacement ratios have the advantage.
I can think of a couple things, besides an even larger sail, that
might boost performance. Leeboards that are adjustable; both fore
and aft, and up and down, would almost surely help. And canvas washboards
or side decks would be an improvement. These would allow me to heel
more confidently, without fear of getting swamped. Then again, maybe
I've peaked out with this particular hull, and it might be time
to start tinkering with a different one.
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