[brian eiland]

Originally this gamefishing cat started out as a motorsailer concept. So I thought I would add this discussion to this thread:



Motor/Sailing Catamaran Concept
(defining ‘the best boat to undertake a world cruise’)


I sincerely believe that a well conceived Motor/Sailer is the most practical, capable, comfortable, safe, economical vessel for serious ocean passagemaking......while retaining the ability to fully explore the most remote, and often shallow coastal regions of the water world.

Even in Beebe’s book,”Voyaging Under Power”, the bible of the power-only crowd, his vessel, “Passagemaker”, was a motorsailer, albeit smaller rigged than he really wanted. Many of the examples he offers as prime passagemakers are instead prime coastal cruisers, ‘semi-displacement’ hulls not optimized for long passages, but rather coastal cruising, where rapid transit is a primary requirement, while fuel use and surviving ultimate conditions are secondary considerations. ‘Trawlers’ today are gravitating toward these semi-planning hull configurations, and twin engines, as buyers become reluctant to accept slow 7-9 knot vessels. And forget wide appeal of primarily sail-powered vessels, particularly with our aging population, so how about those old versatile motorsailers.

We don’t hear much of motorsailers these days....not a popular subject. The old traditional, stoutly-built vessels, with a hefty engine(s), were necessarily compromised in both their sailing and powering statistics. Let’s modernize the motorsailer. The multihull planform holds great promise to improve this breed. The long slender hulls of the catamaran vessel have proven real efficient to push under both power & sail.....not only efficient, but not limited to the traditional slow displacement/length hull-speeds. Just what the motorsailer needs....far less compromising increases in both sail and power performance, while maintaining an economy of operation that truly allows a sea-kindly, long-range capability.

Let’s explore a 40' example. Take the single 120-140 hp diesel used to push the conventional 40' single-hulled trawler or motorsailer to a maximum 8.3 knots hull speed and divide it into two smaller 60 hp diesels driving two long slender catamaran hulls. Voila!, maximum to 15 knots under power with the reliability of twin engines and the stability of a twin-hulled vessel. Add a modest sailing rig to these easily driven hulls, and you now have a passagemaker capable of cruising 12 knots under sail/ power compared with those older 7-knot boats. With 12 knots of speed at your command, you can really take advantage of 'weather windows' to: 1) make your passage as smooth as possible, 2) make some lengthy passages you might never have considered in a slower boat. This multihulled vessel will likely be slowed less by an obstructive seaway, and will accordingly make a passage at almost twice the average speed of the single-hulled vessel...twice the speed for the same total HP. There is an economy of operation here that cuts fuel requirements and bills, and greatly extends their range. In light airs, running one engine often is all that is needed to bring the apparent wind forward to make the sails work harder, and the combination provides much better results than either motoring or sailing alone…… sailing synergy/harmony, the motor taking over in the lulls and the rig taking over in the puffs.

The sea-kindliness of multihull craft is being rediscovered every day. Continual experiences with whale watching boats, fast ferries, pleasure, commercial, and military applications are all proving the validity of the multihull form. What many people forget about a good ride in a heavy sea is that it is very much a function of weight in addition to hull shape. More weight, more robust, more form resistance it offers to moving thru the ocean, the more the sea acts to resist the vessel's progress, and thus the more uncomfortable ride, and we must slow down. A big headsea is a particular challenge. Heavy boats carry their momentum into each trough and crest in a battle with the sea, while lighter weight vessels with slender hulls slice through with less battering. Per a sign at the Naval academy, “you can out-think the ocean, but you can’t out-slug the ocean.” Modern materials allow for lighter boats, and we must properly distribute the vessel's weight throughout long slender hulls. Following seas tend to pick up broad sterns and slew a vessel off to either side....broach. The catamaran hull does not require these broad sterns.

Storm survivability should be considered at the design stage for any vessel making offshore passages. Loss of power (clogged cooling or fuel filters, restricted air supply, water ingress, etc) often occurs at the most inopportune time (during a storm), and this can put the solely powered vessel at peril in short order. A vessel with a modest sailing rig could save your life, and that of vessel itself. Add a proper sea anchor installation, and I would challenge a hurricane. The catamaran planform was rated ‘best in survivability’ in huge breaking wave tests* carried out by Lock Crowther at the prestigious Univ of Southampton. See note below.

Most innovative item on my vessel, the mast-aft sailing rig, also referred to as a ‘single-masted ketch’ ......a marriage between a cutter and a ketch without the mainsail. I have LOTS of data to support my contentions as to the aerodynamic superiority of this configuration.... But lets leave that theory out of the equation for our motorsailing application. The ketch rig is a good small-crew size rig, particularly where all three sails are roller furling!....even a novice could learn to operate this rig.....and she balances under a variety of sail deployments. Lower force centers add safety. Boats with moderate rig proportions tend to make faster overall passages because they are sailed at a higher level of capability than if they carry a lofty hi-performance rig. No big head-bashing booms, and simply wing/wing the headsails downwind. The sail rig contributes damping action to the rolling in a beam/quarter sea (no servo-fins needed), contributes to an unlimited range, and ultimately it will get you home if the engines fail. Ahhhh motorsailing!

Optional nacelle-mounted centerboard precludes any extra hull penetrations, and permits maintenance without hauling-out. ‘Pointed’ deckhouse shape conforms to apparent winds, significantly reducing drag. Flying control bridge & a crows-nest…what a hoot! Dedicated engine rooms, isolated from living spaces. Optional copper-nickel hull material below waterline is impact resistant and naturally antifouling for years.

Accomodations!! How might it appear as a real estate ad?, “Waterfront cottage, 4/5 bedrooms, three baths, large kitchen & dining area, big deck, wonderful views.” Hard to beat a catamaran’s spaciousness and privacy....witness their current popularity in the market. Seamanlike layout... no vast open spaces.

My 65' Motor/Sailing catamaran is the embodiment of a Phil Rhodes’ motorsailer design that has haunted me all these years. Only, this vessel is so much superior. Twin 100hp diesels will cruise her at 12/14knts. Under sail she could make 18/20kts. Range, unlimited. Fuel consumption, extremely low. She could skim over depths as little as 3.5'. Explore those rivers, mangroves, coves, lagoons. Beach the bows. Dive or fish the flats and the reefs from the Bahamas to the Pacific atolls.
THIS IS AN EXPEDITION PASSAGEMAKER!! , 20-25meters, no crew required.


*Note: reference source, Lock Crowther Designs
“This work (tank testing at Southampton Univ) has indicated that the well designed catamaran is remarkably safe in breaking waves up to considerable height, even when beam on, we were unable to capsize a power catamaran yacht in the largest wave which could be generated. This corresponded to a 52' wave for a catamaran of 40' beam. Scaling this down to a typical 24' beam cruising cat means she should be O.K. in a 31' breaking beam sea. An equivalent size mono-hull power boat was easily capsized by a 25' breaking sea, and in tests with conventional yachts after the Fastnet disaster, it was found that a 40' mono-hull yacht could capsized in a 12' breaking sea.”

[brian eiland]

Originally Posted by brian eiland

from last year...I brought a scale model of this vessel design back from Thailand recently and tried to get into several boat shows (one here and two in Europe). No luck yet finding an exhibitor I might piggy-back onto. I am now actively seeking to get to the Miami show. I believe I can get a spot in the 'strictly sail' portion of the show at the Miami Marina....so that might be my best bet this year.

But I wonder about a small display spot in the 'Yacht & Brokerage Show' area up on Collins Ave. It would appear my bigger dollar customer would be attending here. If I weren't on a table, I have in mind a 'coat rack' type of display with the 24" model raised up at eye level. Wouldn't take up much space. Anyone down there in Fla have any ideas who I might speak with??

Well lets try again this year. Last year I put the model in the 'sail section' of the Miami show, and just as I anticipated from being in the sailing business for some number of years, the response was interesting 'for the moment' of the show, but nothing positive came of it. My vessel is a bit high priced for this crowd, in general. I need to be in a 'YACHT' area.

I've tried for several years to get some response from the people at the Ft. Lauderdale show. I'm lucky to get a return eMail or letter 2-6 months after the show has occurred, Obviously they have a waiting list of people wishing to display at this show, so they're not going to worry about one little guy who hopes to display his idea on a budget account. I'm not marketing a whole line of product here that could justify a big budget marketing outlay. I have a rather singular concept of a sail-assisted fishing vessel that may gain some increased interest as our fuel cost escalate. I also get an increasing interest to the motorsailer concept from which this fishing vessel evolved.

I plan on attending the show this year to get a lay-of-the-land feel, having not done so for several years. I will probably pack up the model and take it along, just in case something comes up. Should anyone have any suggestions as to someone I might approch about piggy-backing into a small portion of their spot, I would appreciate any leads. Thanks, Brian

[brian eiland]

Originally Posted by brian eiland

How about 5-8 dollars in Europe now. My motorsailer/gamefishing catamaran is beginning to look a lot more attractive.....particularly should you wish to reach the Line Islands in the Pacific or the potential marlin birthing area in the Charlotte Bank off Brazil.
And do you really believe prices are going to decline rapidly again now that China and the other Asian countries are in the world market big time for fuel supplies to keep their boiling economies going.

This vessel might be a bit slower, but it doesn't require a mothership to reach those remote areas.

For those interested in the subject have a look at this Tara Vana article.

Originally Posted by trouty

What self-respecting powerboater would be caught dead on a sailboat?
I can tell you!

A charter operator - for whom fuel costs is a huge part of his operational bottom line!

I reckon you are onto a winner myself...Cheers!

Just thought I would resurrect this old subject thread considering our current fuel outlook for this coming summer.

[Kevin]

$100 per barrel by June...? Or July? Sooner or later, I see it coming.

[Sean]

interesting read. i like the idea of a wind powered trawler that can operate at competition speed without the noise of most competition vessels. the diesel electric technology available to commercial vessels today is also (i feel) beneficial for where you're heading with this concept. being able to trawl under sail then hook on a billfish and be able to have complete control of the vessel i believe is completely within reach today. it may just be a matter of correctly juggling the control/implementation on the vessel. the cat setup works for perfectly as well for maximising tackle available deployment and or guest access to the stern. what sort of size range are you envisaging this concept being practical for?

[brian eiland]

Originally Posted by Sean

....what sort of size range are you envisaging this concept being practical for?

With the style rig I show here I do not think a vessel less than 40-45 feet qualifies.

Originally Posted by Sean

...the diesel electric technology available to commercial vessels today is also (i feel) beneficial for where you're heading with this concept

I agree there. I am particularly interested in this latest 'rim-drive' technology as associated with electric propulsion (diesel-electric).
http://www.yachtforums.com/forums/technical-discussion/3961-rim-driven-propellers.html

And I believe there is a case to be made for a less sophisticated kevlar belt driven rim propulsor in a jet-pump configuration....looking at that now for a smaller RIB adaptation (actually the one or two tenders for the 65 gamefisher)
http://www.yachtforums.com/forums/technical-discussion/4470-jet-drive-vs-prop.html

I had a pretty serious inquiry on a 85-100 foot version of this design (without the fishing gear) for fast cruising with small crew, but it fell through. Now talking with a prominent gamefishing group about the concept.

[Sean]

would 100' be about the max that it would scale to? id imagine past that size the rigging may start to get slower to control and the sniper like characteristics of the vessel may decline.

interesting reads on the propulsion. one thing ive noticed with most jet driven vessels ive been on is that they're noisey. the small impellers with a high revolution are never going to be quiet. it would be interesting to see what the performance of the belt driven system is like in real life.

i would have thought tho that simplicity and noise levels would be primary goals for propulsion and that a d-e setup using DC motors that are directly connected to the prop shaft without or minimising the use of gears and mechanical transmission would be a good choice. why this? well its essentially the same system that has been used in submarines for a long time and the technology is quite mature. plus you can have a lower rate of revolution then a jet type setup. i wonder if there is a pod solution along those lines that wouldnt increase the draft greatly. variable pitch propellers too it would be a shame to use a traditional prop today when there are so many new options giving extraordinary manouverability that would be so valuable on a cat.

keep us posted

[brian eiland]

Originally Posted by Sean

would 100' be about the max that it would scale to? id imagine past that size the rigging may start to get slower to control and the sniper like characteristics of the vessel may decline.

I think you're right there. The forestays begin to get too long

interesting reads on the propulsion. one thing ive noticed with most jet driven vessels ive been on is that they're noisey. the small impellers with a high revolution are never going to be quiet. it would be interesting to see what the performance of the belt driven system is like in real life.

The rim-driven prop units are reportable very quite as to have that extremely close fit between high tip speed props and the outer wall of the tunnel. Note that I am only proposing the belt-driven rim- drive configuration as an alternative to the more complicated electric-driven rim for very small craft (RIBs) that might be able to take advantage of newer generation, more efficient jet-pump drives.

i would have thought tho that simplicity and noise levels would be primary goals for propulsion and that a d-e setup using DC motors that are directly connected to the prop shaft without or minimising the use of gears and mechanical transmission would be a good choice. why this? well its essentially the same system that has been used in submarines for a long time and the technology is quite mature. plus you can have a lower rate of revolution then a jet type setup. i wonder if there is a pod solution along those lines that wouldnt increase the draft greatly. variable pitch propellers too it would be a shame to use a traditional prop today when there are so many new options giving extraordinary manouverability that would be so valuable on a cat.

keep us posted

The D-E setup could make use of just DC electric motors directly driving conventional props, ala submarines.

But in a sailing mode it would be nice to be able to retract the props rather than contend with less efficient folding ones. A rim driven electric propulsor might well offer that retractability, along with azimuting also, plus quite operation and less interference with fishing lines. You might even be able to pull the propulsor out for maintainence without hauling the vessel

[nas130]

Are any of you actual fisherman????

Trolling with sails alone?

Generally diesels raise fish!!!

Mabye the waters your heading to are better than the ones I have fished.

Nick

[brian eiland]

Hello Nick,
First off let me say I am not an experienced ocean fisherman, but I have listened to and read a number of their stories.

And one statement I present on my website that is bound to create a lot of controversy (I've got my body armor on for the replies);
"I've also heard the many claims by various captains about their individual boat's particular sound being an attraction for raising fish. I find it difficult to believe that a very loud (water is a great amplifier and transmitter of sound), foreign sound would act to attract a large predator fish seeking out their food source in the ocean's natural environment. Loud, unnatural noises have in most cases acted to disperse aquatic life."

"Tara Vana, the only other professional sailing/gamefishing boat (catamaran) I know of, certainly excelled in the fishing tournaments off the Pacific island of Bora Bora "

I found this website listing a few of their tournament wins;
TARAVANA'S maiden 18,000 mile voyage included fishing stops in Valdivia, Chile, the Galapagos islands, Costa Rica, Mexico, California, Hawaii, the Marquesas, Tuamotus and Bora Bora. Since TARAVANA'S 1995 arrival in the Leeward Islands of French Polynesia, this unique vessel has compiled an impressive list of celebrity, international clients as well as an impressive fishing record. Captain Richard Postma has been fishing the Leeward Socitey

Islands for over 20 years. Some of TARAVANA'S recent tournament victories include:

• 1st Place: 1999 Overall Points for Bora Bora Tournament Season
• 1st Place: 1997 Inter-Island Championship
• 1st Place: 1997 World Billfish Series
• 1st Place: 1996 Women's International
• 2nd Place: 1995 Inter-Island Championship

[daiwa]

See the video, very simple to add fishing chair back of the both pontoons if needed for 2 fishers. Secondly, for my opinion this is one manufacturer who indeed made a serious success with design concept as sailing catamaran - not surprize for me it´s french, they might be rude for turists, but they indeed know how to made catamarans.

Also, the commercial video by itself is best practise of advertising (= very well done)>>>

http://www.yapluka.fr/yapluka_us.htm

Just select Video of of Yapluka70´1

[brian eiland]

Originally Posted by daiwa

See the video, very simple to add fishing chair back of the both pontoons if needed for 2 fishers.

Thanks for adding that video reference, I had forgotten it.

For the fishing layout it is not just simply a question of adding two chairs. You will note that this was also done on Taravana:
http://www.runningtideyachts.com/archives/TaraTour2.html

http://www.runningtideyachts.com/archives/TaraSoundings.html

http://www.runningtideyachts.com/archives/taraarchive.html

If serious fishing is contempated there needs to be a much more serious attention paid to the cockpit layout. I have collected a few good articles in reference to this subject including a good one from Professional BoatBuilder. I have had a few short conversations with Peter Wright (very well known name in offshore fishing), who has indicated a willingness to help with this cockpit design with a serious client. And I have recently made contact with another potential source of help with this aspect of the design. There are lots of subtleties involved in this detailed area.

Where less serious fishing is involved, simply adding two chairs is very adequate.

I might make one other observation. Carrying the yacht tender in davits, or on a portion of rear deck, at the stern is unacceptable on a fishing vessel. I am working on a new tender design that would allow for the craft to be carried up in the bow area, but not become a liability if swamped with a wave.

[daiwa]

Less professional fishing, I am not fisherman for living , Yapluka seems to have exactly the same hull available also as 85 feet model, but none has been build yet. Perhaps one thing which could be a nice extra to the hull would be copy frontseat from Lagoon, nice place to read while backwinding, but overall - this is pretty much perfect design which I like, 95 feet model looks too much hometrawellercat for me and even bigger start´s to require crew to handle.

[brian eiland]

Originally Posted by daiwa

Yapluka seems to have exactly the same hull available also as 85 feet model, but none has been build yet.....pretty much perfect design which I like, 95 feet model looks too much hometrawellercat for me and even bigger start´s to require crew to handle.

As I mentioned above I had a pretty serious inquiry on a 85-100 foot version of this design (without the fishing gear) for fast cruising of the Mediterranean with a small crew, but it fell through due to a family illness. Actually they initially inquired about an 85-120 size, but I worked it down to 100. Even at that I really believed the 85 fitted their needs much better when they emphased non-commercial, family use, with a small crew. I wanted to keep the length of those forestays and the size of the sails to a reasonable size.

[daiwa]

Not sure why do you mention this for me, but if you want my opinion I think you had fallen a few major mistakes with design for which reason I would not even consider it seriously. Certainly that just my opinion, perhaps your modell&factory will be success story.

There´s a number things,

1) One key feature to own cat is to have real walkaround boat, deck in your hulldesign looks pretty hard to walk ahead and around. Lagoon has even went further to adding outside "soffa" frontside of the hull. This is one idea of cataraman to have a real walkaround feature.

Because your outdoor design overall is very balloon there´s not much flat space&work&walk if needed. Any change of the sails ie. requires crew to work ahead of the hull. Also second level(flybridge), which usually is most popular space for people to stay is strange way to small when considering the boat size even if your would add flybridge option. It´s also sun and raining protection roof for the maindeck where dinner&entertainment has been planned to be ie. dinners.

2) Catamaran pontoons from the backside should be well sized, to design "backsteps", in your design they are far too small and seems to not carry overall hull royal way. For me it looks like a there´s only 2 sticks where the huge hull lies. See the example for example french factory where this part of the design has been taken cook care>

http://www.sunreef-yachts.com/new_co...1&boatid=5&w=4

Overall this is one thing which all cat factories has understoold.

3) Third issue could be size of the second level ie. flybridge, you had missed a lot of squaremeters for nothing considering the overall size of the boat. Remember second level where boat skipper is also located while sailing is most popular space to stay for all people in the boat while sailing. This is usually one of those keythings which makes cat to have huge squaremeters and space to stay vs. mohohulls.

Also, see one of the most new plan design>

http://www.exclusive-marine.com/page...rticle-30.html

Forth thing came to my mind also, are you trying to start new factory and cat brand with your own designs ? That require a lot and very good / professionals venture capitalists on board, even you would build first boat at your own risk.

Boat concept is only one small piece of it. If you do so, at least turn out from US market for less expensive labor markets like to somewhere to FarEast. It´s not easy to enter to the market which is allready full (=meaning perfect competition running allready), because your boat does not offer nothing new innovation which no-one else does (not including your rig and sails are more than usual) > that in mind only thing where you find yourself from the marketplace is to be competitor by pricing. When price is main reason to buy a boat, then you need to sell thousand exact same model per year. One who is doing that is Bavaria in German
www.bavaria-yachtbau.com - to be exact 3500 boats per year and remember it´s not then customize or even semicustomisized boat anymore and require a massive production lines. Remember that buyers require major and long history of building boats/yachts, backgroud, sometimes also success in sail competitions (actually numbers of builders had started they reputation via this way like Nautor Swan). This all bring to have also decent maintenance / warranty availibityly also.

Overall I think shaping a boat too much it´s not todays design anymore and haven´t see any does it either, even sailingboat bows have nowdays very sharp waterline. However, here´s the indursty biggest builders -certainly there´s number of carage plans exist, but haven´t look at those.

One area where they could be marketplace would be semicustomized scubadiving&entertainment sailing catamarans for turists, business which certainly growing and none of the builders specialized to this area. Those cats looks like also non-professional designs which screams, for my opinion proffessinal design hands.

Certainly, I wish all the best luck with your enterprise. Remember, this only one opinion from the complety other side of the world (if you´re U.S citizen).

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