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  #1  
Old 05-09-2007, 11:28 AM
sharpii2 sharpii2 is offline
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Rowing Sailboat/Sailing Rowboat Race Rule

Hi All:

Here's an idea I got while reading up on the 'Water Tribe' races down in Florida. It is an attempt to encourage sailboats that row well and row boats that can sail well for people who don't want the usual specialized craft that are available today.

So here goes.

LENGTH VS. SAIL AREA ROOT RULE

The concept here is for fair competition between sail powered boats,
Oar/paddle assisted sail boats, and sail assisted oar/paddle boats.
The central idea is that, as a boat gets longer, it gets successively
easier to move through the water. It is for this reason that most 19th
century rowboats were at least 14ft long and most 'sea kayaks' are
around 18ft long. Since human muscle is an inherently limited source
of power, a one person paddle or row boat has a limit to how far and
how fast it can go in a day. A sailboat has no such limit as long as
there is plenty of wind. A race between a 20ft sailing dinghy and a
20ft sea kayak would hardly be fair, if there was any kind of wind
blowing.

Why would anyone want to have such a race?

Because sailboats and oar/paddle boats have perhaps become too
specialized.

In an age of ever increasing fuel costs, people are going
to need a boat that does not need an engine, yet is easy and quick to
set up and can be moved about on the water when there is no wind. A
pure sailboat rarely meets this need. Most are designed for racing and
have rigs designed for maximum efficiency up wind. These rigs tend to
be tall and require rigidly extended stays which need to be tightend
before use. Such boats also require a great deal of initial stability
to hold up these rigs, so need either deep, heavy, ballast or wide
beam. Neither of which is good for rowing or paddling. Rowing/paddling
boats tend to be equally specialized. Extreme examples tend to be long,
narrow, and somewhat tippy.

The idea here is to create a compromise. Something that has the best
combination between sailing and row/paddling capability. The race course
sets up about the most perfect laboratory of what works and what doesn't
that humans can devise.

But any such contest must be reasonably fair. So design trade offs must
be forced. Allowing unlimited length will merely insure that the longest
boat wins. So I propose a trade off betweenlength and sail area. The idea
being that a longest boat would have no sail
area at all. Whereas a shorter boat will be allowed more and more sail
as it gets shorter and shorter. If all boats in this race displace
roughly the same amount, This could be an interesting trade off. The
shorter boat would have a much higher Displacement/Length ratio and
should be harder to row or paddle. It will also have a shorter water
line length also making it harder to row/paddle at any reasonable speed.
To counter this disadvantage, it will be allowed more sail area.

This, in itself, creates an interesting requirement. The shorter boat
will have to be rowed/paddled at the same time it is being sailed to be
at all competititive with the longer boat. This would be introducing a
whole new skill to boating.

To do this, I propose one basic formula along with three stipulations.

FORMULA:

The length of the boat, in feet, will be subtracted from 20.0. What is
left will be squared. And that, as long as it meets the following three
stipulations, will be the allowed sail area.

STIPULATION #1

An absolute limit of 100 square feet will be imposed.

STIPULATION #2

A 'bank' amount of 20.0 sf of sail can be added until the the new sail
area either equals 50 sf, or the 20 sf bank is used up.

STIPULATION #3

The boat must be entitled to at least 4.0 sf on its own to be allowed
any sail area at all.

Here are some examples of boat lengths and the amount of sail they
would be allowed to carry under this proposed rule:

_9ft_____100 sf (stipulation #1)
10ft_____100 sf
11ft______81 sf
12ft______64 sf
13ft______50 sf (stipulation #2) (49+1=50)
14ft______50 sf
15ft______45 sf (25+20=45)
16ft______36 sf
17ft______29 sf
18ft______24 sf
18+ft_____00 sf (stipulation #3)

Now I will compare one boat from each extreme that is allowed to carry
sail as well as one in the average range. Hopefully, I will be able to
demonstrate the equity of my proposal. I will show three values:

The displacement length ratio, the sail area/displacement ratio, and
the square root of the length multiplied by 0.75:

(each boat displaces 400 pounds and is assumed to have a water line equal
to its over all length to keep things simple)

10ft___D/L=183___S/D=29.5___Length sqrt X 0.75=2.25
14ft___D/L=067___S/D=14.6___Length sqrt x 0.75=2.80
18ft___D/L=020___S/D=07.1___Length sqrt x 0.75=3.20

As I hope I have shown, the 10ft boat will be under sail a lot as it
struggles to keep up with the 3.0 knots that the 18ft will be able to
make at a more leisurely rowing/paddling rate. The 18ft boat will probably
only use its sail when the wind is blowing well because it will have so
little of it. The 14ft boat will be nicely in between those extremes.
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Old 05-09-2007, 06:48 PM
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This is interesting. No wind and the longest boat wins (if the sailor can drive it's length). Lots of wind and the planing hulls take off. It's a question of horsepower.
If the weather couldn't be predicted, and only one boat were allowed per sailor, I'd be in the 10 footer (maybe 10 1/2) with 100 sq ft. It will be most able to plane at a lower wind speed, since length isn't needed to plane so much as the right underbody. Then, ghosting, the shorter boat again excels. Reaching hull speed requires some real physical fitness in longer boats, but hull speed for a 10 foot boat (4.23 kts), while slower than its 16 ft competitor's 5.36 kts, will not be so tiring to maintain. The difference may drop to 1/2 a knot once the longer boat gets tired. If the wind then arrives, goodbye 16 footer, who won't get up on a plane without a hurricane, goodbye 9 footer, who is insane but inspiring to watch as he tries to climb the first 12" wave until his enormous sail lifts him clear of the water.
Sounds like fun!

Alan
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Old 05-11-2007, 08:30 AM
sharpii2 sharpii2 is offline
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Thanks, Alan.

This was originally intended for multi day races where it is more difficult to predict the weather. The 'Water Tribe' races all cover considerable distances. The shortest covers over 60 miles. The longest circles the state of Floriday (requiring a 40 mile portage).

Some parts of the race are at open sea where there is usually plenty of wind, and some parts occure where there is hardly any wind at all, which makes the design trade offs that much more vexing.

They have four classes of boats and the fourth class is 'unlimited' sail boats.

The 'unlimited' is a bit of a misnomer as the crew has to be able to drag the boat up the beach at each check point above the surf line.

The winner of the 'Everglades Challenge' was a 22 ft sailboat designed to plane. It had two crew.

I wanted to have sail boats at lesser level of competitition such as 'class three' which is canoes and kayaks converted to sail. I thought smaller sailboats should be able to compete in this same class, but the chief wasn't buying.

I came up with this idea to make sure that, if let in, the sail boats would never chronicly best the converted canoes and kayaks.

These boats typically carry around 125 lbs of stores and equipment.

BTW Your 10.5 footer would only be allowed to carry 90 sf of sail.

20-10.5=9.5. 9.5*9.5=90.25.

As I hope you can see, winning with a shorter boat that planes may not be all that easy. Particularily if the longer boat crew is allowed to row/paddle at the same time it is sailing.

But, that being said, an 8 footer was entered in class four and it came in 10th in the 'Everglades challenge'. That race was a particularily windy race.

Bob
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Old 05-11-2007, 09:21 AM
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Yes, I realized 10 1/2 would mean lower sail area. Sounds like the races would be fun. They would spawn all sorts of hybrids and curiosities.
A lot more fun than the stiffy blue-nose patrician class races that I see up here. A bit more egalitarian.

Alan
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Old 05-12-2007, 11:48 PM
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In any wind a moth foiler would always win. Narrow sailing canoes would also have a huge advantage. This formula would create an extreme design like most formulas do.
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Old 05-13-2007, 10:27 AM
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Would the Moth foiler get up and go if it displaced 400 lbs?

A.
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Old 05-13-2007, 12:16 PM
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Alan, obviously a 400lb. Moth would need a lot of "******" to get up.
Why do the Americans always insist on such heavy small boats anyway?
Is the 400lb meant to be boat, rig, crew person and enough stores to last a week, or what?
If it was boat only 150lb. seems ample, even with a rig.
Looks like the v word is banned from this forum.
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Old 05-13-2007, 01:42 PM
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Quote:
Originally Posted by frosh View Post
Alan, obviously a 400lb. Moth would need a lot of "******" to get up.
Why do the Americans always insist on such heavy small boats anyway?
Is the 400lb meant to be boat, rig, crew person and enough stores to last a week, or what?
If it was boat only 150lb. seems ample, even with a rig.
Looks like the v word is banned from this forum.
Americans insist on small heavy boats? I didn't think so. I think the meaning of the displacement figure was "all up", regardless of how the weight was apportioned. Usually a small boat has weight, and displacement is what happens by adding people and gear.
I think what was meant here was that the boat, sailer, and whatever else went in it could not be less than 400 lbs.
If there were no displacement minimum, a foiler could compete, and the whole egalitarian principle of the formula would be for nothing.
The idea, I think, was to open up racing to many varied craft already owned.
I like this approach because you don't stand on shore watching a dozen identical boats racing, but you happen to own a no-class boat.
The Moth, incidentally, is a great formula because it encourages not just sailing expertise, but design expertise as well. Anyone can be a hero who is smart enough. Anyone with money can buy a first rate regular class boat, but not anyone can buy a first rate design that will win. That takes ingenuity.

Alan
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Old 05-13-2007, 09:22 PM
sharpii2 sharpii2 is offline
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Quote:
Originally Posted by alan white View Post
Yes, I realized 10 1/2 would mean lower sail area. Sounds like the races would be fun. They would spawn all sorts of hybrids and curiosities.
A lot more fun than the stiffy blue-nose patrician class races that I see up here. A bit more egalitarian.

Alan
Precisely.

I in vision this a blue jeans/sweatshirt event or series of events that would be raced with the wind from zero to, say, 20mph. Some days you would row/paddle all day and others all but the longest boats would be sailing.

Bob
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Old 05-13-2007, 09:34 PM
sharpii2 sharpii2 is offline
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Quote:
Originally Posted by gonzo View Post
In any wind a moth foiler would always win. Narrow sailing canoes would also have a huge advantage. This formula would create an extreme design like most formulas do.
Perhaps foilers should be banned for this reason.

Lets face it, foiling is an expensive and tricky technology. Maybe thats why we don't see fleets of foilers right now. Despite their blistering speed.

I have not yet heard of any foilers going camp cruising yet, but I will not be surprised if it happens.

It's not so much that I am down on foilers, but rather I think they should race only amongst themselves.

Their inheirent speed advantage practicly mandates that.

Who knows. Maybe foilers will someday replace conventional sailboats.

But then again that's what was once said of multihulls.

Bob
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Old 05-14-2007, 01:15 PM
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Around three years ago I decided to design and build an outrigger canoe for 2 persons with a parachute spinnaker, carbon mast, and minimal sailing hardware. This ended up being 22'6" in length with a 14 ft carbon windsurfer mast, and a 66 sq. ft. spinnaker. My son and I had endless hours of fun paddling upwind and then sailing back to the starting point. After a few outings I had the idea that this if it was a development class with certain broad rules and specs, it would be a fantastic and interesting form of racing. Sometimes in light winds the spinnaker gives a lower speed than paddles, so you then douse the spinnaker. Also paddling a fairly large outrigger canoe into a strong breeze is physically challenging. In strong winds the downhill ride is very quick and exhilarating. I saw the potential of a great competition emphasizing paddling skill, physical endurance, and sailing ability. Furthermore it could be quite tactical deciding on what angles of the race course the spinnaker would be a viable option, and when it wouldnt be. I never followed up as I believe that Australians generally would not see this as a worthwhile form of sport. Aussies would much prefer to be full on canoe buffs, or into pure sailcraft, not a hybrid boat, as mine is. I might be wrong about this, but a strongly suspect that it would not attract any interest in my part of the world. More the pity though, as regular racing in small boats although fun, has been "done to death" so to speak, and is definitely in decline in Australia.
If any Aussies are interested in this concept please speak up and I will provide more info on the boat.
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Old 05-14-2007, 08:51 PM
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A Moth with crew will displace close to 400 lbs.
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Old 05-15-2007, 01:47 AM
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400lb- is that light?

Hi Gonzo, I refer back to my comments that Americans always build heavy small boats. You may not agree with this statement, but you say that a Moth with a crew will weigh close to 400lb.
Sorry, but not in Australia. Fastacraft foiler Moths weigh 30kg or less fully rigged. This is 66lb. Australia' top Mothie Rohan Veal weighs around 70kg. This is 154 lb. Even allowing for some clothing and buoyancy jacket, say 10lb. this all totals 230lb. Much less than 400lb. Some-one please come up with a realistic set of facts that show me that Americans do NOT build their small boats too heavy!
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Old 05-15-2007, 08:46 AM
sharpii2 sharpii2 is offline
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Quote:
Originally Posted by frosh View Post
Around three years ago I decided to design and build an outrigger canoe for 2 persons with a parachute spinnaker, carbon mast, and minimal sailing hardware. This ended up being 22'6" in length with a 14 ft carbon windsurfer mast, and a 66 sq. ft. spinnaker. My son and I had endless hours of fun paddling upwind and then sailing back to the starting point. After a few outings I had the idea that this if it was a development class with certain broad rules and specs, it would be a fantastic and interesting form of racing. Sometimes in light winds the spinnaker gives a lower speed than paddles, so you then douse the spinnaker. Also paddling a fairly large outrigger canoe into a strong breeze is physically challenging. In strong winds the downhill ride is very quick and exhilarating. I saw the potential of a great competition emphasizing paddling skill, physical endurance, and sailing ability. Furthermore it could be quite tactical deciding on what angles of the race course the spinnaker would be a viable option, and when it wouldnt be. I never followed up as I believe that Australians generally would not see this as a worthwhile form of sport. Aussies would much prefer to be full on canoe buffs, or into pure sailcraft, not a hybrid boat, as mine is. I might be wrong about this, but a strongly suspect that it would not attract any interest in my part of the world. More the pity though, as regular racing in small boats although fun, has been "done to death" so to speak, and is definitely in decline in Australia.
If any Aussies are interested in this concept please speak up and I will provide more info on the boat.

Fosh:

If I may tender some gentle critisizm.

Your boat may be great fun for you and your son, but at 22ft it is quite long. And, seeing that you only mention down wind sailing, it seems a little lacking in capability.

I can understand why it is not widely copied.

When I dreamed up this idea, part of the goal was to keep the boats within reasonable lengths. That is why I noodled it so an over 18 footer would end up with no sail.

Another goal was to encourage the developement of good multi purpose boats that went without engines.

Actually, the genisis of this idea goes quite far back for me. I thought about what if a sail boat race is schedualed and the wind doesn't show up?

Or the race has to be completed within a certain deadline and there is insuficient wind for the speed such a deadline requires.

In short, I thought of this as more a racing class for developement than a developement class for racing.

The hope was that these boats may be raced on Sunday but actually used for angling, excercise, and just plain relaxing during the rest of the week.

Bob

P.S.- Your boat probably would have done quite well in this year's 'Water Tribe' 'Everglades Challenge'. The race was around 300 miles long and mostly down wind. And the winds were quite strong this year. Your boat would have been a fairly good Class Four entry. In class four, length and sail area are not limited, but you have to get under some pretty low bridges and through a passage way that is 11 ft wide. You and your one man crew must also be able to haul your boat and gear up the beach past the surf line. From how you discribed your boat, it seems like it would have met those criteria quite admireably.
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Last edited by sharpii2 : 05-15-2007 at 08:58 AM. Reason: To add more comments
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Old 05-15-2007, 03:11 PM
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Sharpii2 thanks for your well expressed comments. First of all why did you start this very interesting thread in this section, when you would have more exposure under "Sailboats"? Also what has this to do with a true motorsailer? Not meant to be a criticism, I am just curious.
My Outrigger canoe is quite long but I carry it all on an MG station wagon, on roof racks, so for me it is not that big nor heavy.
My inspiration was from the wonderful Hawiain OC6 which is usually paddled by six people but many have sailing rigs. I have only one son so I reduced the OC6 to a 2 man version. It was never planned to be anything more than a one-off for our own pleasure. Also I was desperate to find out if I could successfully design and build a boat in cold molded plywood as I have always been a great admirer of this boat building technique. I am happy to say that it turned out even better than expected and will definitely outlive me and maybe my son also, as it is bulletproof but very light. BTW it is carbon sheathed. Rowing boats for recreation or racing if they are not full-on racing shells (Olympic games stuff) are almost unknown in Australia. Also paddling with a single blade as the Polynesians do seems far more interesting than a double blade, which I have done also in the past.
I know that in my part of the world the competition that you envisage has no chance of happening, but I will follow the progress of your proposal in the US with interest.
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