PDRacer Sailboat

Lateen Sail
The lateen has a yard along the luff, and a boom along the foot. Has all of the great qualities of a lug sail, yet doesn't have the bad twisting that the lugs have. Can be hoisted and secured with a single halyard just like the the lug sail.

This is Ken Abraham's boat, his sail has a luff of 12'0", foot of 11'4", leech 11'0". The total area is about 62 sf. Made with curved luff and foot, they are 3" curves at 30% back, or as close as Ken could guess.

Ken originally experimented with a sunfish sail, it had a bad habit of making the boat windvane and point directly into the wind, going into irons. Think it was because a sunfish sail is so much longer than the boat. Ken say this lateen he made is much better and he can control it just fine - since he has been leading us point wise, the sail sure is proving it's place !

The lateen can be easily reefed by running a line of grommets from the tack to the leech, and lacing a line thru them. A traditional lateen (the original sail configuation) has a loose foot, meaning it doesn't have a boom on it. It just had a long yard along the luff of the sail.

Crab Claw
This sail is very similar looking to the lateen, however it can be rigged in several ways that make it very different. The boom is usually very high, and the leech is usually cut with significant hollow to give it a claw look. These were often used on polonesian sailing canoes, which their high boom was a great benefit so that the crew could paddle and sit on the outriggers without the need to worry about being hit by the boom. Their biggest advantage should be in light wind or in tree protected areas where the large amount of sail area up high can catch more wind than a lower sail.

Here is an excellent essay for crab claw sails.

Marconi
This is the typical sail you see on most modern production sailboats. It is basically a big right triangle. To keep the sail from twisting at the top, they need to have a vang pull the boom down.

Leg-O-Mutton Sprit (3 sided sprit)
This is the sail that was originally specified on the Bolger Brick. It is a tall skinny triangle like the Marconi, except that it has a sprit boom. Because the sprit boom is rather high, the bottom portion of the triangle pulls it down making it self vanging, and also keeping the boom high so it doesn't hit you in the head. Also like the marconi, they require very large masts. One trick sailors do is to add a club to the clew of the sail (shown on the right), this will increase the total sail area by a small amount. Also since the sprit boom goes thru the middle of the sail, there is a "good tack", and a "bad tack" where the sail shape is spoiled by the sprit boom.

Gunter
This is one solution the the problem of tall masts, the Gunter sail uses a yard that is hoisted vertically, and is used with a shorter mast.

Mast Aft / Jib Only
Many sail rigs are declared to be the most effecient and best performing. This is the only sail that I really believe, it is a single large jib sail only with a mast placed aft in the hull. The theory is that it has a clean luff without a mast to spoil the air flowing around it, and it is easy to control the shape. There are several significant problems with the rig, the mast is placed right where the helmsman sits, and it interferes with the motion of the tiller. Also to make it work properly, there has to be a large amount of tension along the luff, so heavy wire and big chain plates are a must. The rudder can be controlled with a tube going down through the hull, or the most un-orthodox solution I have seen is to have a rudder attach to the bow moving the steering to the front.

This is a boat called a "SoDoIt", it was originally conceived as a class rated solo racing boat for cross atlantic racing. To my knowledge, it never took off but does have an interesting solution for the Mast Aft / Jib Only sail plan. She uses a stayed bipod mast which is stood near the stern. The bipod mast is made by using 2 smaller masts, the bases at each gunnel, and the heads are joined with a cross piece towards the top. Stays to the stern corners plus the forestay hold the mast upright. This rig also has 2 additional struts that go forward from the mast for additional support. Here are a couple more photos of the rig:
pic 2
pic 3

The Fleche boat uses a different aproach to fly a jib only, instead of stays to hold up the mast, she employs a tripod mast rig. For more info on Fleche [click here]

General Comments About Triganle Sails:
PROS: Because of the triangle shape, there is usually a very small amount of twist in the upper part of the sail making it very effecient and usually point very high into the wind.

CONS: Most need longer spars, so you will probably have to make larger spars than you can buy. They are usually taller rigs, so will have more weight aloft, and more heeling force for the same amount of sail area. Since usually laced to the taller sail, you can't drop them on the water, but you can release the boom and curl the sail forward. The square sails produce more power per square foot on all points of sail except to windward.

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