New low-cost "hardware store" racing class; input on proposed rules

So, you add a spinnaker to get 4 times the sail area but only get 3-5 percent more speed?

Does not sound like a good trade off to me.

 

Maybe thats a reason(if true!)to not outlaw spinnakers.... Let the designers decide on the tradeoffs they want to make.

 

I am not sure about the 3% number. It really depends on the boat.

My old trip 40 without a spinnaker almost couldn't go down wind, with it the boat was ok. But it also has a huge mast for the boat size, a fractional rig, and a 12' J. Compare that to an Olson 30, where the spinnaker is much larger relatively, and in 15kn of breeze we routinely hit 12kn instead of 5 downwind.

The asymetricals are even more pronounced. I just got to sail a new design called the VX OD. Rocket ship fast upwind thanks to a very small jib, rated at like a 95%, but downwind with the kite up we were routinely in the 18+kn range in 20kn of breeze. I wouldn't have enjoyed bobbing downwind with small fractional jib much though.

 

That's speed round the track, and for various reasons that aren't relevant here the Canoe is probably an extreme example.

But lets consider a simple boat that travels at around 4 knots going round a 4 n/mile w/l course. It will do the run in 1 hour and the beat in around an hour and a half, so two and a half hours per lap. Put an enormous spinnaker on it so, gybing downwind, it does the run in half the time it takes two hours per lap or only 20% faster. On the other hand it was probably doing 11 knots through the water instead of 4 on that downwind leg.

Add to that the effects of apparent wind. When beating the apparent wind means if you go faster you get more breeze across the deck and increase available power. Running faster there's less apparent wind and less power available to the rig.

So that's why upwind efficiency is almost everything, and its only worth increasing downwind performance if you can do it without compromising upwind, which is why the spinnaker scores.

So if you are perfectly happy at 4 knots all the way round, and 4 knots downwind feels a lot slower than 4 knots upwind, then that should send your rule set in one direction, and if you are not content with that your rule set should go in another.

 

It.s easy to imagine we live in an age where sail has been perfected. Certainly carbon masts and mylar sails allow strength and light weight.

I think sail reached a higher degree of perfection in the "Days of Sail".

The clippers, being the epitome.

The square sail was much wider used than fore and aft sails, for a reason. More power.

Normally, vessels carried their square top sails after reefing/furling all others.

The spinaker is the modern version of the square sail. Instead of a yard at the top, a spinaker pole holds the tack to weather.
The square sail became nearly extinct because of crew size requirements. Not inefficiency. IMHO

 

Wait a cotton picking minute guys. We have an amateur built, hardware store boat that will be used by a lot of beginner sailors. Spinnakers are an instrument of the devil in unskilled hands. Chutes will send a poor sailor swimming if he makes a klutzy move. If he does not capsize he'll dump the rag and it'll tangle around the rudder or some other disaster. Besides, they are expensive and this is to be a low budget boat. The original aim was to encourage newbies to build and sail a boat on the cheap. So keep it simple already! The hot shots can graduate to a 49er or an FD when the time comes.

 

Messabout, no one was saying the rule should encourage spinnakers - some of us were merely noting and explaining how (1) many non-racers, including fairly new sailors, love them and they are not merely for racing boats; (2) that whether a modern rig has a spinnaker or not doesn't seem to change their design greatly; and (3) they are in some ways an inefficient way to use sail area if it is restricted, but on the other hand they do compensate for the fact that you can carry more rag downwind than upwind and therefore can make sailing many boats a lot more fun.

Yobarnacle, given the speed/length ratio of square riggers, it's hard to see that square sails were more efficient. And of course, that ignores the fact that they became outmoded in yacht racing, even downwind, by more modern sails.

Surely you don't think that sailors in competitions like the America's Cup "Deed" challenges, round the world racing, development dinghies, windsurfers, C Class catamarans etc are too stupid to use the most efficient rig possible?

 

A not so obvious advantage of square sails on huge ships was the fact that the wind was almost always on one side of the sail. That way, foot ropes could be set up behind it and men could stand on those lines to set and furl the sails.

Also, the sail area could be divided into smaller sails, one on top of the other.

Large schooners were built during that era too, but the fore and aft sails were so huge they needed steam winches to raise and lower them.

The smaller square sails usually furled to a standing yard.

This way, you could have a much larger ship and endow it with a considerable sail area.

The windward inefficiency of the square sail was hardly a problem, at that time,(turn of the 20th century) as most of the voyages were down wind and steam tug boats were around to drag them into harbor.

The square sails weren't more efficient. They were simply more suitable.

 

The problem with spinnakers in racing, is that they are usually un counted sail area. Once used by one, they will become mandatory for everyone else.

That would be the main reason I would ban them.

Not because they are no good, but because they are too good.

They also favor taller rigs, as taller rigs can carry larger ones.

If I were to allow them, they wouldn't be allowed to have any more area than the largest upwind sail on the boat.

My Siren 17 didn't have one. It had a high shouldered 'drifter' instead. It was set the same way an ordinary jib was and was little trouble at all to use. It also was capable of all points of sailing, including upwind.

I never sailed the Siren 17 directly down wind, unless I wanted to scare the pants off my passenger. I preferred to tack down wind instead.

 

So! I guess a scaled down topsail schooner will not be permitted, huh? Rats! Sure is a pretty rig!

 

Messabout,

I am with you all the way. I have seen more than a few experienced crews on large displacement keel boats broach and almost pitchpole when flying a spinnaker (they were lucky no one went for a swim). They are a lot of work to keep under control and in a dingy race takes a lot of crew discipline and skill to use them effectively. All the extra rigging they require also strike me as an extra hazard, particularly if you pitch pole and both crew get tangled up in it. Too many things that can go wrong, not for entry level sailing. The idea is to develop good all around performing dinghys, you will not see people flying spinnakers off of dinghys just for fun, only in a race.

I want to keep the boats simple, I would NEVER consider a spinnaker simple. an over sized jib/Genoa or smaller asymmetric one might be okay, but not a spinnaker.

You want to try a square rig, have at it. There are good reasons they are not used anymore, they are not efficient. Too much weight and drag for the amount of thrust they yield. Typically they define a spinnaker as having a horizontal dimension larger than half the distance between top and bottom of the sail area. So a square rigger would not be disqualified as a spinnaker.

 

Another idea crossed my mind, since the boats are supposed to be easy to transport (hence the size limit), should there also be a max weight limit?

Weight in a dinghy is usually not helpful, but if someone put on a weighted swinging keel or something, along with a very large sail, it might have an advantage in large winds, but would not be easy to transport.

Perhaps such a rule it is not necessary, but I thought to share the idea to see if anyone has an opinion about it. The purpose is to allow the boats to be cartopped or easy to move around on land.

 

Hey Petros,

With a 16' mast limit on a 14' boat, I can't imagine anyone getting a significant racing advantage out of trying to swing a heavy keel. This said, allowing some form of weighted centreboard may open up oportunities to sailors of limited physical capability (sailability etc) which would make a positive addition to your group. There also seem to be a number of folk who want to try keelboat ideas on sit-in small yachts, wheres the harm in that, so long as they come along an participate.

I think the complexity of a spinnaker will price its self out of contention. We all know that a $600 budget will be enough of a challenge without the extras. Kites would not be easy to make from hardware store materials, they obviously need to be light enough to fly but still very strong.

I think in reality the budget cap will prevent most undesirable traits making their way into your class, the only exception may be the use of very narrow waterline craft that require great skill to sail. But even so we all aspire to be as good as the best guy in the fleet, having someone faster makes us try harder and innovate.

If someone can make a DSS system for $100, it works and can last all season then something worthwhile has been achieved. The flip side is if someone with a wholesome family cruiser heads back for the shed and builds something a little more radical the next year and then faces the challenges of getting it to sail..... then sailing is the winner.

I think your rules as they stand are fine, go build some boats, go sailing before your summer gets too much older! Leave the rule tweaking for next winter.

 

I do wish people who clearly don't know an awful lot about racing class measurement wouldn't post this sort of nonsense. It just isn't true and hasn't been for many decades. There are a tiny handful of classes worldwide which don't measure spinnaker area, and the majority of those don't measure any sail area at all. There used to be problems with sail area measurement back in the first half of the last century when over simplistic meaurement rules were used.

Spinnaker area is normally measured separately from the fore and aft sail area for the reasons that ought to be obvious from my post above. Because any reasonably efficient boat sails in far less apparent wind downwind than upwind many classes find it desirable to increase the sail area downwind. Its a damn sight easier and cheaper to pull a kite up and down than it is to have a double size rig and put a reef in and shake it out every lap.

If you don't want spinnakers in your class that's perfectly reasonable, but if you have a moderate sail area limit then there's no need to ban them, they just won't be used. If you don't want a sail area limit then things get a lot more complicated, and the scope for rule evasion and peculiar developments increases considerably. If you have a sail area limit then its probably best to use the ISAF sail area measurement rules, which although they look complicated are very free of potential rule evasions. If you try and reinvent the wheel and work out your own simplified measurement system the smart money is that you'll also reinvent some of the old measurement problems of the beginning of the last century.

I do hope you're joking and you don't really believe that... Those of us who sail the performance boats wouldn't dream of heading downwind without the kite up in almost any circumstances.

The trouble is the alternatives for adding sail area downwind are even more complicated. See if you can find a photo of a 19thC Skiff complete with ballooner jib, ring tail and water sail...

As I think your rules stand at the moment I might work from a starting point like this sketch. Note exaggerrated freeboard forward and "cargo hold" in front of the mast. With the ballast in boat will sail with exaggerated bow down attitude and the first level of flare immersed. Red spotted sail is a balloon type jib to be poled out downwind on a very long whisker pole. Sail is not gaff rigged but has a very long top batten. It probably won't work with such a long batten, there's be a lot of trial end error... It would be decked across without any kind of cockpit other than the cargo well, which hopefully could be made self draining.
I can't think such a craft remotely desirable, nor what you have in mind so maybe you should think about what features need to be discouraged in the rule set. There's a lot of expertise out there in writing rules, which is a suprisingly difficult exercise. SHC knows a lot about it.

Oh and whilst a maximum weight limit rule won't do any harm, I wouldn't spend an awful lot of time worrying about framing it if I were you: I'd be astonished if it were approached by competitive clraft. A minimum on the other hand... I might beware of permitting ballast at all though, the history of ballasted boats is of every increasing ballast ratios with resulting structural problems.

 

Pretty good sketch.

A bit too Beamy. The preliminary rule is 7ft max Beam. Your sketch looks more like 10 ft.

The problem with going with a narrow waterline on a boat this heavy (approx 11 cf displacement), is you won't get the hull fine enough for super displacement speeds, (going narrower at the WL will make it deeper) and it will be harder to get it to plane.

This strategy worked with with a 'Moth', because that boat was mostly moveable ballast (the crew). I don't know how much the typical 'Moth' weighed, so I'll wing it (no pun intended) and guess around 90 lbs. Winging it again, and my guess for this proposed class is closer to 200 lbs, not including the 'cargo'

I can conceive boats of this class planing in some conditions, such as down wind in blowing conditions.

You are right. I am very ignorant of dinghy class rules.

But I will say this:

The fact that sail area in this preliminary rule is not measured is a good reason to ban them. Or, as I have suggested in another post, limit their area to that of the largest upwind sail (probably, but not necessarily, the main)

I like the geometric constraints for the rig size with this proposed rule. A Gunter or lateen would be about the only two ways past the mast height restriction. Otherwise, rectangular sails will have to be used in order to get ample sail area on a one mast rig. I don't think we see enough of these more practical sails on pleasure boats, and this preliminary rule seems to encourage them.

I can imagine a huge balanced lug working out well in this class.

It is relatively easy to reef and maintains its CA quite well when reefed.

One I have in mind would have a 14 ft Yard, a 14ft boom, and carry about 152 sf of sail. This would give an S/D of around 30.