THE SQUARE SAIL
Running with the wind can be difficult, and on the
Columbia river, the westerly wind can blow at your back all day. The main has
to be brought out at ninety degrees or so to the boat, and the jib becomes
useless unless it is forced on the opposite side with a pole. Add a mizzen to
disrupt the wind and it’s a mess. Accidental jibing is frequent, and dangerous.
A spinnaker is one solution
but somewhat out of character for an old style
gaffer. Spinnakers also require a long pole, are typically huge, and
somewhat temperamental.
I came across a possible solution
in an excellent article by Martin O’Scannall in Classic Boat (Feb. 2008, pp. 22-26) entitled ‘Squaring Up’. He goes
over the advantages of a square sail and outlines a set up for a cruising
sailboat, in his case a 5 ton gaff cutter, with a 28 foot length and 8 foot
beam, namely, the beautiful Sauntress.
In his set up, the yard
stays up permanently (for the length of the cruise at least) and the sail is
hauled up or down as need be. He diagrams the rigging, with useful hints and
comments, and provides dimensions.
O’Scannall also goes through
the old literature, demonstrating how his rig is based on the practical wisdom
of famous sailors who cruised with square sails, including my favorite, Conor
O’Brien.
His sail is approximately
200 square feet on a 16 foot yard, 16 feet in height, and has a foot of 12
feet. That is clearly more than I need because my boat is much lighter at 1.5
tons.
I calculated the sail area
needed to ‘push’ my boat at a desired speed using the formula:
A=(S/16)*(d^2/3)
A: area in sq. ft.
S: speed in knots
d: displacement in tons
For the Sauntress, I assumed a speed of 7 knots. The area comes out to 209
sq. ft., which is right on.
For the 20 foot Ann-Martin, I assumed an optimistic
speed of 4-5 knots, requiring an area of 53-67 sq. ft. It surprised me how
small the sail’s area had to be. Keeping a 16 foot yard, I cut the tarp to a
height of 10 feet and a foot of 9 feet; the area comes out to roughly 120 sq.
ft, which is more than enough. Esthetically, anything smaller looks like a toy.
I might have a reef line put in if and when I have a cloth sail made.
The sail having a shorter height than
on the Sauntress, the problem arose of
estimating the width of the foot, which has to be wide enough to clear the
halyards. On the Sauntress, the foot
just clears the deck. With its 8 foot beam, there must therefore be about two
feet of clearance on each side to get around the halyards. On the Ann-Martin, the foot is well above the
deck, at a height where the halyards are closer together. I measured a
clearance of two feet on each side, so I
think it will work out.
I made the yard from
dimensional lumber. Rumaging through a pile of 2”x6”x16’, I found a straight one
with desirable grain. I cut a 2” or so strip, let it dry, rounded it to a
thickness of about 1.5 inches, and encased it in a biaxial fiberglass sleeve
and epoxy. It’s quite stiff. I’ll apply a few coats of spar varnish when it
warms up.
One objection that I read
about on sailing forums is that a square sail adds too many lines. Well, get a
motor boat – it has no lines at all. Yes, there are more lines, but I don’t see
it as a valid objection unless it makes sailing more difficult. With a square sail, you gain ease of handling
going downwind, with no need to jibe. Besides, one sails for the pleasure of
handling sails, and a square sail invokes history and tradition.
Another complaint is that
square sails are only good for trade winds that blow in the same direction for
days on end. I prefer to think of this square sail setup as a spinnaker, of
which I see plenty on the Columbia river. O’Scannall’s rigging is easier and
faster to put up than a spinnaker. The center of effort of a square sail is
over the center of the boat rather than beyond the bowsprit, as with a
sipnnaker. It is therefore safer and more comfortable.
Of course, I doubt that most
forumites have ever deployed a square sail on a small boat. I’ll judge first
hand and report back. At the very least, it will look cool sailing up to the dock
at the wooden boat show this summer.
I’ve inserted some pics of
an unfinished tarp sail, and minimal lines, with the boat on its trailer. I’ll try the sail out for
this year to assess whether or not it’s worth having a square sail, and then choose its final
dimensions if so.
