Design Challenge III

[Woxbox]

Re: Design Challenge III

The windward in a gale requirement is traditionally met in two ways: mass and lateral plane. The mass keeps the heavy traditional boats moving -- they can punch through the waves, and when in deep troughs between big swells will keep going until the next one lifts them and exposes the rig to another blast of air. The lateral plane from long, deep keels just allows them to hang on even when the boat really wants to slide downhill sideways.

Multihulls can easily get adequate lateral plane -- as noted it can be too much; some give is a good thing. The mass issue is the sticking point. Long slender hulls don't require the force to keep moving that a heavy traditional boat does, but they most certainly go through a big acceleration/deceleration cycle even in a moderate sea. And a breaking wave becomes a braking wave, too. A tall rig may help the boat grab air throughout this cycle, but I don't know that a race hard to windward in a big sea and gale conditions would be easily won by a multi with, say, equal sail area to a heavy cutter.

But the real question is how will the judges figure this out when reviewing the entries? Will it be a judgement call, or is there some sort of computer model they'll test against?

[Tom Lathrop]

Re: Design Challenge III

If I were a designer, I probably wouldn't bother with a contest like this unless I thought there was a market for the design when I'm done.

This brings up a real issue with any such challenge. It takes much work and time to provide an entry to one of these events. The rules stipulate that an entry must be a new design. For a professional, how do they justify that if there is no opportunity to market the resulting design? One issue I have with the way WB handles these challenges is the minimal amount of coverage given to the entries. Even an amateur must think twice about putting in the effort when their design may never even be seen. At a minimum, the comments of the judges should be made available to the entrants. That is just fair. Is it asking too much for WB to at least make these entries available on the website? I think not.

As to the specific rules, I think WB has made a good decision to make them more difficult. 47 knots to windward is a real challenge, especially to those who have not actually experienced it. That should cause more creative thinking and generate some interesting designs. Good boat designs are more evolutionary than revolutionary and it is rare that outside of the box thinking produces boat designs that prove out well in practice but we shall see.

Small civil aircraft designs are a good measure of this. With all the changes and advancements made in the last 70 years, most small current aircraft look almost identical to those from the 1940s'. The air is even more unforgiving than the water and major deviations are quickly weeded out if they have any flaws. Apologies to Burt Rutan who stands as the exception and rare genius in that field.

[Daniel Noyes]

Re: Design Challenge III

Multihulls can easily get adequate lateral plane -- as noted it can be too much; some give is a good thing. The mass issue is the sticking point. Long slender hulls don't require the force to keep moving that a heavy traditional boat does, but they most certainly go through a big acceleration/deceleration cycle even in a moderate sea. And a breaking wave becomes a braking wave, too. A tall rig may help the boat grab air throughout this cycle, but I don't know that a race hard to windward in a big sea and gale conditions would be easily won by a multi with, say, equal sail area to a heavy cutter.

But the real question is how will the judges figure this out when reviewing the entries? Will it be a judgement call, or is there some sort of computer model they'll test against?

There's nothing mentioned about a sea state, so the designers entering are assuming flat water but gale force winds, mabey a 2-3' chop, basically protected water. I think this is simply a criteria to weed out freekish boats with ridiculous cabins and exceptionally high topside... basically the boat must be a real sail boat, not a floating house or party barge with a sail.

If 15-20' breaking seas were part of the design challenge it would be mentioned!

[Woxbox]

Re: Design Challenge III

gale force winds, mabey a 2-3' chop

In my neck of the woods, even in protected waters a gale kicks up more than that in short order. A little more detail in the rules would be a handy thing to have.

[keyhavenpotterer]

Re: Design Challenge III

There seems to be some divergence in Europe and the US to what is a 'raid inspired' event or boat.

In Europe 'Raid' events have substantial compulsory rowing only parts. The good 'raid' boats must thus combine good sailing and rowing performance which is a difficult task. You can turn up with anything, pulled with anything and go out in anything. Natural selection has shown that the optimum to build, sail, oar, trailer is a Ness Yawl pretty much. People turn up with Bayraiders, more specific sail boats, but they can't row well enough to compete overall.

In the US, the rowing aspect seems ignored or neglected, instead a 'raid' event seems interpreted as mainly a coastal cruising/ race event.

I do feel, that incorporating compulsory rowing sections is important to maintain the 'raid' events identity as something different, encourage people and boat designs to not use engines (less future environmental pollution) and to evolve and produce a boat with its own, and very green, identity, separate from just fast dinghies. It also maintains a historical connection to the past and provide a contemporary usefullness close to a dock and greater self reliance. The growth of raid events in Europe shows that this is a strong image.

Its good to have a challenge which opens up new avenues, designs and options, and I realise it says only 'inspired by raid events' and I'm personally all for 'fast expedition sailboats', but dropping the compulsory rowing aspect as seems to be happening in the US, I feel could be a mistake.

The competition has alot of merit and I'm keen to see the winning entry as much as anyone.

[antoniv]

Re: Design Challenge III

Greetings from the Mediterranean Sea (Balearic Islands, Spain).

I'm a young industrial designer and amateur nautical designer and builder. I am very happy and excited about this new challenge, the ship described in the rules closely resembles the ship that I want to design and build for myself and to sell in kit form.

To be honest, I will not reach the maximum parameters of the challenge. I will always think of my needs and my potential clients. For me the maximum length of 40 'and weight of 3,500 lbs are simple delimiters.

The most important thing for my design is:

That is really a good performance boat under sail and row. The rowing is not intended as an auxiliary propulsion, the ship must perform well with two paddlers and allow a comfortable position for rowing.

Must be affordable for car trailers (1600 lbs max in Europe) and are easily launched and rigged with only one person.

Allow a comfortable accommodation for two people and multy-day cruising.

Here in Mallorca, we don't have quiet lakes or bays so you can meet with a storm of 34-47 knots that comes without warning. If indeed my boat should be perfectly able to navigate in poor sea and wind conditions.

And all that combining the best of traditional wood construction and modern design.

I hope to get a good ending

[Tom Lathrop]

Re: Design Challenge III

Antoniv, A good attitude and I agree with your parameters.

[Antti Alfthan]

Re: Design Challenge III

Smelling like those fast Ladoga boats / Dutch "snick" to me. To modern standards of course. The original boats were open. Either rigged to one mast, gaff sail and jib (snick) or two masts and spritsails (Ladoga "saima"). Especially good in windward. Both have a similar, characteristic stem (and stern) - and a few things under the waterline in common.

For spartan accomodation there could be enough of foredeck to sleep under, room under the aft deck for other vital needs. Water ballast midships under the main deck level right above waterline - hence sturdy bulkheads fore and aft of course. Auxiliary propulsion: rowing.
Clincker built. I have the feeling a 9-10 m long all wooden boat wouldn't be too heavy to meet the standards.

Too bad I'm not a boat designer

[amdesign]

Re: Design Challenge III

Hmm, I already know what can work for this contest, and later can become good stock design for amateur builders and small yards.

[antoniv]

Re: Design Challenge III

@Tom Tank's for your comentary and I also agree with your words.

The history and natural selection show us what are the best ways to face the sea and use.

I show a Llaüt, the classic boat of the Mediterranean designed and evolved for a great performance in rowing and sailing (from when the engines did not exist) your sail area are very divided, with very low sail center to accommodate all possible wind situations.

http://www.vistaalmar.es/hablame-del-mar/modules/upload/attachments/Imagen0064.jpg

Now the next step is to define the minimum and maximum dimensions of design.

One factor that defines the maximum dimension is that the ship should move correctly with the strength of only two rowers. In addition, this factor also defines a maximum beam and drawing a narrow and sharp boat forms.

The factor that defines the minimum size is to accommodate two people in your cabin.

I believe that a length between 6-7 meters (22-23 ft) would be a good starting point.

[spirit]

Re: Design Challenge III

Years ago I saw a two-person ocean-going plywood kayak about 22 feet long that resembled a submarine. In cross section it was oval (about 3 1/2 feet high and perhaps 4 feet wide). Its owners, a sturdy couple, spent most of their time miles offshore "paddling among the whales." They lived aboard in their cockpits and double bunk, and had a generous galley and storage. When I saw them, they had pulled their boat up to a cabin for an overnight with shower, using a two-wheeled dolly. They were eating mahi mahi they had caught. There was some water ballast, and they had weathered some very nasty storms. I didn't see a mast or sail, but balanced sails and a leeboard could obviously be added.

I thought that this was a very appealing boat, and bet that a clever new design along these lines would indeed be marketable.

[wtarzia]

Re: Design Challenge III

[QUOTE=spirit;2715168]Years ago I saw a two-person ocean-going plywood kayak about 22 feet long that resembled a submarine. In cross section it was oval (about 3 1/2 feet high and perhaps 4 feet wide). Its owners, a sturdy couple, spent most of their time miles offshore "paddling among the whales." They lived aboard in their cockpits and double bunk.../QUOTE]

--- That sounds so good! Sigh... -- Wade

[Daniel Noyes]

Re: Design Challenge III

I do not see the weight limit as any sort of difficulty for a mono hull design. It seems pretty obvious that the designs will not be keel boats but boats that develop the majority of their sail carrying power from their form stability. The 3,000 lb weight limit is easily within the weight of any performance 30 footer and could accomodate a 40' monohull with little or no effort... I think the multi hulls wil have to be nearly as weight conscious as the monos.

Years ago I saw a two-person ocean-going plywood kayak about 22 feet long that resembled a submarine. In cross section it was oval (about 3 1/2 feet high and perhaps 4 feet wide). Its owners, a sturdy couple, spent most of their time miles offshore "paddling among the whales." They lived aboard in their cockpits and double bunk, and had a generous galley and storage. When I saw them, they had pulled their boat up to a cabin for an overnight with shower, using a two-wheeled dolly. They were eating mahi mahi they had caught. There was some water ballast, and they had weathered some very nasty storms. I didn't see a mast or sail, but balanced sails and a leeboard could obviously be added.

I thought that this was a very appealing boat, and bet that a clever new design along these lines would indeed be marketable.

I'm trying to envision how you paddle a kayak thats 4' wide and 3' high, long paddles, I suppose these royal barges/ dragon boat types in the far east are close to these proportions but they have 50+ paddlers and they just paddle on one side... also I have never seen a Kayak with double bunks or a galley, never mind both!
sounds like some aux. sail power could come in very handy on a kayak of these proportions, make it an interesting expedition boat.

[wtarzia]

Re: Design Challenge III

... I'm trying to envision how you paddle a kayak thats 4' wide and 3' high, long paddles, ...

--- I was thinking they paddled it like a canoe, from fore and aft cockpits near enough to the ends to enable a canoe-paddle stroke, though perhaps depending on the end-shapes, a kayak paddle might work? If the center sleeping-cabin used a narrow cut-out down the center, fabric-covered for weather, as in some of the Birdwatcher-like designs, then crew could travel along the center without crawling over the cabin-top? -- Wade

[antoniv]

Re: Design Challenge III

I'm still working on the preliminary studies to my design proposal.

The maximum dimensions of the boat that I want to design are bounded to the maximum load weight of light-trailers in Spain: aprox 500 kg (1100 lb). And the maximum width of the load on the trailer of 2.40 m (+- 8ft)

For this my design can not exceed 6 meters (20ft) .

Now I wonder, what conditions are the minimum for a comfortable accommodation for two crews on a weekend costal cruise ?