22m cruising cat design concept [Archive]

Becaris

08-03-2008, 02:13 PM

OK, to start with, I am not a yacht designer. I do make a living creating concepts (though until now, not yachts). What this means is that NOTHING about this design is necessarily correct, and I know it. However, there are a few things I'd like to say about what I'm trying to achieve.

I set out to create the concept for a forward flybridge / semi-pilothouse sailing yacht over 20 meters long with a biplane rig. I do not want to turn this design discussion into a discussion about single or biplane rigs. I would rather we discussed what it would take to make a biplane rig work best on a cruising cat this big and other issues with this design.

Beyond the biplane rig, there are other areas of the design that I would be interested in 'why not'. Like the forward flybridge, the nacelle center, various ratios, hull shapes, mast positions, pretty much anything that comes to mind.

I know this does not look like a standard cat, but that's the point of a concept. Let's take a look at something different, and figure out if it could work, and what it would take to make it work.

If suggestions are made that seem good, I will adjust the model and repost pictures. So, here goes... take a look... discuss away... have some fun.

(These screenshots are now old, if you look deeper in the post there are new pictures with changes suggested by other readers).

rwatson

08-04-2008, 06:20 AM

I think the design has some interesting aspects.

I wondered if the 'downstairs' forward windows would be better off with an inward slope from the 'flydeck'.

The 'step' caused by the jump from the downstairs windows spoils a nice aerodynamic shape.

sandy daugherty

08-04-2008, 09:10 AM

There seems to be a common theme that sailing vessels are controlled from a 'driver's seat' like a car or an airplane. In reality, watch standers don't spend hours on end sitting in one place, even if all or most of the control lines are led to a single location. Since things don't happen at 55MPH or mach .82, and since there isn't a double white stripe down the middle of every sea lane, Its much more important for a watch stander to be able to get in and out of the helm seat easily to check all the things a watch stander should watch than to make it some kind of throne. That means standing headroom . And standing headroom means one very big lump right up front in your design. Since it is also important that the helmsperson be able to see 360 degrees, and it would be very nice for him to see the corners of the boat for docking, it begins to look a little unwieldy.

Consider dual helm stations, connected through the forward upper deck. Place them forward of the masts, with a clear view fore and aft, blended airodynamically around the mast base, with windshields that roll around to provide open air and egress to the bows, or closed and heated with the main cabin. If the boat is large enough, some horseshoe shaped seating around the helm would keep the Captain the center of attention.

Becaris

08-04-2008, 11:29 AM

I agree with you Sandy about not needing to stand at the helm during a watch. However notice that the interior station is part of the salon (and includes a horseshoe shaped seating area behind the helm as does the flybridge). With the windows arranged in a half circle the interior station has good visibility (accept directly astern). And from the flybridge (which is set ahead of the masts, due to the rotating unstayed masts and no jibs) you also get very good visibility, even astern.

Incidentally, both the flybridge and pilothouse stations on this concept are both designed for more social aspects and gawking together while there is something to see (not racing at 55). The design idea is simply taken from other flybridge/pilothouse designs used in passage maker motoryachts that only go about 8 knots. With the design of the two unstayed masts, there aren't lines and winches to run, which allows for some similar design. The idea with this cruiser was to allow a couple to sail a larger yacht with less physical need and more comfort.

I feel that placing dual stations around each mast would put the main cabin in the way of good visibility. However, your point about docking has some merit, I will consider additional controls aft (port and starboard) for docking.

There is a question for you captains, at slow docking speed, using dual engines to get into postion at the dock, do you need access to your rudders or are can you just leave the rudders centered and use the two engines to maneuver?

However, besides docking visibility issues, what other issues do any of you see with this layout? I can give you some interior pictures of the inside helm/pilothouse area if you want.

Becaris

08-04-2008, 11:36 AM

rwatson,

I'll try some designs with the front windows angled forward from the bottom of the flybridge.

RHough

08-04-2008, 11:53 AM

I feel that placing dual stations around each mast would put the main cabin in the way of good visibility. However, your point about docking has some merit, I will consider additional controls aft (port and starboard) for docking.

There is a question for you captains, at slow docking speed, using dual engines to get into postion at the dock, do you need access to your rudders or are can you just leave the rudders centered and use the two engines to maneuver?

Docking is about the only time the skipper has to be at the controls and able to see well. Once you are away from the dock, the autopilot can drive.

No need to give up rudder control for P&S docking stations. Go with a 'fly by wire system' based on the Volvo IPS or Cummins Zeus. Steering, throttle, and gearshift are all electronic. A wired or wireless remote could be used on the fly bridge and carried to where the skipper needs to be. The state of the art is good enough that they use it to get crane operators out of the cab and allow them to stand where they can better see what they are doing, it is a natural for controlling a boat for docking.

Just a thought.

Becaris

08-04-2008, 01:30 PM

Excellent, then I can leave my two steering stations where they are (which are more about looking at electronics than steering the boat most of the time anyway) and use a remote when docking. In a pinch, there is hull side visibility from the extreme sides of the flybridge anyway, I did a ray trace from the proper height to make sure.

Becaris

08-04-2008, 01:38 PM

Here is a look at the concept model with forward slanted salon windows at the front, as suggested by rwatson above.

Nordic Cat

08-06-2008, 02:56 PM

May I suggest that you lower the height of the coachroof if possible, maybe open up the sides of the flybridge deck a bit to give an "lighter" look. The boat looks top heavy.

I am about to commence on the build of a 15m bi-rig cat, with rotating wingmasts. It's interesting to see that there are more bi-rigs being built and designed nowdays. Maybe shorten the boom vangs a bit also, take a look at the elegant solutions by Eric Sponberg, maybe get him to design the masts for you. He is one of the few designers who has done it several times

Regards

alan

Becaris

08-06-2008, 03:16 PM

Thanks for the suggestions. I agree with the height, I was already working toward lowering it. I left the leading edge of the flybridge as I needed that height, but lowered the rest by more than a foot. I may be able to lower it more as well.

As for the masts, I'll take a look. :)

Becaris

08-06-2008, 05:20 PM

Here is a shot with the coach lowered (I lowered the boom down to the new coach height). The flybridge is lowered, but not as much, though the majority of the coach roof is much lower now.

rwatson

08-07-2008, 06:35 AM

Yeah - thats getting there nicely.

The only thing that caught my eye was the bulgy bit over the prop. To my eye i would probably think about making the stern run a bit concave so you could have the prop shaft a bit more horizonamontal.

Nordic Cat

08-07-2008, 05:33 PM

Try angling the aft end of the saloon to get a less chunky look. Play around with side window shapes to "lighten" the look as well.

The curve of the transoms don't fit in with the rest of the boat - no balance.

What are you going to use the roof on the saloon for? probably need some clearance under the booms.

It's getting there...

Alan

Becaris

08-07-2008, 07:15 PM

Right now I'm using the flat roof for solar panels... lots of solar panels. I want this to be a hybrid electric powered sailboat. I've read up on the issues with this, but I think the time is ripe as new battery technologies are coming available that will allow more power storage at lesser weight and faster recharge times. So I'm planning electric motors, solar panels, two wind generators (one on the top of each mast) and of course, a diesel generator for emergencies (no wind, no sun, out of battery power). Is there a reason I need some clearance between the boom and roof (solar panels)? If so, how much?

As for the prop and hull shape, anyone have a picture/diagram of what the hull shape should be in profile to accommodate the props correctly?

When it comes to the aesthetic shape of the coach, windows, and even the curve of the transoms, I'll modify that some once I have some of the more functional aspects adjusted. Any suggestions on that end? Hull shape, width, mast height, mast position, boom length, etc.?

I can supply better measurements of any area if needed.

rwatson

08-08-2008, 06:17 AM

For a bit of fun, I touched up the prop area.
I 'felt' that you would need a skeg based on the centre of effort of the sails

:-)

Becaris

08-08-2008, 02:59 PM

Thanks for the prop picture suggestion. Here are the latest screenshots with all changes so far (including your new prop/hull change). Any thing else? Anyone? Beueller?

rwatson

08-10-2008, 05:36 AM

I think I would like one of these!

Question, why a boom when you have the wishbone sprit?

If you beefed up the sprit, you would do away with the need for head crushing booms perhaps?

Another thought out of left field, why not start that wave splitting edge under the bowsprit and extend it back under the cabin. That would give that little bit more of spray protection and lift from the odd big wave maybe?

Becaris

08-10-2008, 12:19 PM

The shape of the mast, boom, wishbone, length of boom, height of mast, are all areas that I don't know enough about to create an efficient design. I was hoping that I could get some more knowledgeable people to chime in on this area.

In my lack of full understanding, I added the wishbone connection to the boom to act as a kind of reverse boom vang to keep the boom from flexing down so that I could get maximum sail as low as possible to the coach. I was going with the idea of keeping the sails center of gravity as low as possible.

If I'm headed off in the wrong direction, or if you can tell me anything else I've done wrong in the sails, masts or boom, please, jump in. I'll make the changes and repost the model pictures.

rwatson

08-11-2008, 06:47 AM

You are absolutley right about the reverse vanging effect, and keeping the area down low.

As long as you have two curved wishbones, you vould do away with the boom altogether - saves weight and expense, and on this rig, it seems to fit right in

Grizz

08-11-2008, 09:32 AM

Will the sails blanket each other? Would the power of the sails be more efficient if one mast was forward of the other one? Like a piroge rig, or cat-ketch as it's more recently called. With the sails seperated by the hull CL distance the power of the slot effect is lost, no?

Rambling,

Grizz

Becaris

08-11-2008, 11:02 AM

I don't know about the slot effect, could you (or anyone) address this in more detail? As for positioning one mast in front of the other, there will always be an angle of wind where one sail blankets the other, so I'll just keep them parallel.

I've already decided to go with the two mast setup, using unstayed carbon fiber masts. I've done this to make the yacht easier to sail by a small crew, and safer. To gain these two advantages I've made the decision to suffer the drawbacks, one of which is the blanket effect when on a reach. While sailing her in that condition I would follow other people's advice and let out the windward sail to 'spill' into the other, and even more often, adjust my heading to get out of a strict reach.

As for the other disadvantage, getting through the wind while tacking, I'm not concerned with this. Of course I hope she turns well enough to handle that, but I can always use a bump from the electric motors to pull her through. Finally, as for the 'fun of sailing' argument against twin unstayed masts, I enjoy being on the sea, but the sails are a means to an end for me, cheap propulsion.

I'm seeking more automation so that I can control everything from a single location (flybridge or pilothouse), without having to venture out to the bow much during sailing, and to keep messing with winches and lines to a minimum. This is one reason the coach shape and forward flybridge and pilothouse look so different from other cats.

Anyway, that's all I want to say about single or twin masts. What I really want to know is how to position my twin unstayed masts (more forward, more astern, which side and how close to each hulls center line?), how tall to make them, how long to make the booms, etc. Thanks!

rwatson

08-12-2008, 06:24 AM

There are quite a few boats that have used this twin mast setup over the years, with all the types of comments you are making about the pros and cons of the rig.

Unstayed carbon fibre on a boat this size will be enormously expensive, but hell - the boat wont be cheap either.

I think you are going to have to turn the concept over to a naval Architect as soon as you have ironed out all your priorities and compromises. This will be required to do calculations like mast location, and general certification that will allow insurance companies to take you on. Asking for 'opinions ' on this site will get rid of some of the obvious flaws, but will not come close to providing the complete solution.

You have about $20,000 of design work to be done after your concept drawings, and perhaps half a million to spend after that on the boat.

It might have been another post, but the1much observed that the Naval Architect will just about start from scratch despite you hours of thinking.

I think you are now at the stage of putting a request for an NA in the appropriate forum, and start to get some 'professionaly indemnified' work done. I got some great responses for my project, and as you know there are some very clever people on this site.

Go for it! :-)

mikereed100

08-12-2008, 10:34 AM

The new drawings are an improvement and the flybridge and hulls blend nicely. To my eye, however, the cabin seems "clunky" and does not blend well wih the hulls and flybridge. I think this is mostly due to the large, flat panels, size of the windows and angle of the cabin sides. I would love to see a drawing with more vertical cabin sides in which the window height and width matches that of the windows on the flybridge. Perhaps a slight forward slope to the aft side of the cabin as well would help.

I'm looking forward to comments on the nacelles. It looks like the shape you have drawn would go a long way towards alleviating bridgedeck slamming.

Mike

Becaris

08-12-2008, 10:37 AM

Yes, I agree. I already knew I'd have to pay a professional to do the actual design. However, I'm just trying to get the concept as close as possible so that they start with a concept of what I'm looking to build, then they can tell me I'm crazy. (it won't be news to me).

So what I'm looking for now is just obvious adjustments (obvious to others, news to me).

Nordic Cat

08-13-2008, 05:04 PM

I would expect the masts to be a bit further forward in the hulls. Place them so you get the best possible bury in the hulls while still allowing passage past them below.

The centre of effort for the sails need to be roughly above the CoE for the underwater sections including keel etc.

I am not keen on the steps on the sides, they break up the lines of the boat....

just my 2 cents

Alan

Becaris

08-13-2008, 09:10 PM

Thanks for the suggestion on the mast position. As for the stairs, I'll leave them for the moment, I'm going to show pictures of the interior layout and open a discussion on why I am putting what where soon, then once again have people tell me 'why not?'. Until I show those shots and open those discussions, I'm going to leave the functional aspects involving those parts of the design alone.

You see, I'm not trying to just make a pretty yacht here. Now... don't get me wrong, I will try to improve the lines and look and take suggestions to improve the looks, but I am far more concerned with function than good looks. I have very specific needs in the yacht I will eventually build and sail around the world, which is why I'm busy with this early concept.

This yacht needs to handle blue water sailing, but... it also needs to be ready to act as an almost motor yacht for when I reach various ports and places where I want to move around some while not under sail. This is part of why the design has a flybridge forward.

Also... I plan to have her up in cold water zones at times, which is why there is a pilot house, and why I want her to sail or motor with the least amount of work on deck as possible. Hence the pilothouse configuration and bi-plane unstayed masts.

I also want her to rarely use any diesel fuel. This is why there will eventual be a large array of solar panals on the coach roof, twin wind generators (one on each mast top) and electric motor propulsion/charging.

Much of the design is predicated on the idea that new better, lighter batteries are on the horizon, and should be available in five years (about the time I might be finishing the build of my yacht (whatever that ends up being past the prototype stage).

So... it's a different kind of yacht, and therefore a different kind of layout. Now, if all this will all work together... maybe?

brian eiland

08-16-2008, 01:10 PM

From the sounds of what you are after, you might pay a visit to this site:

The Eco-Trimaran - a motor ship powered soley by renewable Energy

http://www.oeko-trimaran.de/eco%20trimaran.htm

...but I suggest you have a healthy wallet. I think this fellow has already spent a lot of money and time.

On the other hand you might consider something more realistic:
New Age Trawler/Motorsailer; Kite assisted PowerYacht
http://www.boatdesign.net/forums/showthread.php?p=171356#post171356

Back to those design concept drawings by Humphrey’s (attached PDF). I can fully imagine a scaled-down version of this tri-hull design, in the 65-70 foot range, with a wonderful rear ‘swim’ platform deck incorporating a sportfishing arrangement and/or a Scuba diving platform. Just inside could be a tender stowage as shown; or rather a complete diving & fish tackle facility. The tenders could then stow up on rear deck, or one forward, one aft.

The power would be a single main engine sized to develop the vessel’s desired top speed, and it could transmit this power by conventional shaft/prop arrangement, or with a azimuthing Volvo IPS dual prop unit, or via a retractable azimuthing Rim-Drive prop unit as I included on my latest dynarig motorsailer design.
1) Volvo IPS : http://www.yachtforums.com/forums/yacht-reviews-feature-stories/7467-world-debut-volvo-pentas-new-ips-750-850-a.html
2) Rim Drive : http://www.yachtforums.com/forums/te...ropellers.html

Supplementing this single main engine would be a single DC diesel/electric power unit to provide for:
1) Ships electrical requirements
2) Slow speed operation by electric (wing) motor belted to main prop shaft
3) Maneuvering thrusters as required depending upon azimuth capabilities of main prop.

The entire ship would be powered by only two engines, basically sized to provide:
1) Full main diesel power, unimpeded by interceding diesel/electric conversion
2) Slow speed operation and ship’s systems via the smaller diesel/electric unit
3) ‘Twin power’ emergency backup as either engine can run all gear
This configuration more ideally meets the latest thinking for the new diesel/electric DC technologies onboard smaller vessels. Alternatively, two identical diesel/electric plants might be sized such that in combination they would supply the max power required of the vessel, and half power for lesser times.

Only two engines and no conventional sailing rig should make this a more affordable vessel, both in construction, in maintenance, and in operation. However the SkySail kite arrangement will probably more than offset the conventional sailing rig in cost. Possibly a less expensive alternative to this ‘brand name’, with less computerization could be found (no integrated weather/navigation features, etc). Light-weight construction would be desirable but not necessary. Third world hull construction materials are a possibility.

I’ll call it a KiteSail Motorsailer for now.

This is doable now, and maybe in affordable epoxy saturated wood. And it would have a resale value when you want to upgrade...everyone does eventually.

Becaris

08-16-2008, 02:06 PM

The problem with that yacht concept it is just too radical for me. Even though I'm interested in as 'green' a boat as possible, I'm also looking to go with more tried technologies. There are already electric motor powered cats, and several biplane rigs. I'm just looking to combine these two existing designs into one and add some of the better battery storage coming from the hybrid car boom. Finally, make use of the biplane rig with unstayed masts to add a flybridge and pilot house control area. Nothing on my concept is that radical. Right now I think it is only about 30% of the way there, I'll be trying to reduce the size some, make it lighter and more streamlined. Add a few small innovations, etc. Nothing too radical.

brian eiland

08-16-2008, 11:08 PM

The problem with that yacht concept it is just too radical for me. Even though I'm interested in as 'green' a boat as possible, I'm also looking to go with more tried technologies.
I assume you are speaking of the Eco-Tri rather that the Kite-Assisted vessel??

Becaris

08-18-2008, 10:03 AM

brian eiland

05-26-2009, 03:04 PM

Yes, sorry, I was talking about the Eco-Tri. As for the Kite-Assisted vessel, the problem there is that it is primarily a motoryacht, while I'm seeking primarily a sailing yacht. That vessel is also just way to large for what I need. Even my current concept is too large.
I'm currently scaling her back to about a 16 or 17 meter version.
Sorry but I'm a bit confused here as to what vessel you are making reference to being too large?? Are you referring to the Eco-Tri as being way too large? I assume so. And then I would believe you also consider the Humphrey's design (40M) as too large as well?

Note that I had suggested a 65-70 foot version of the Humphrey's design tri hull. That might even be reduced to 50-55 feet to fit your size requirement. She offers a lot of deck area for her size.

But then the tri-hull configuration offers less interior. So at that size go with the cat version (http://www.boatdesign.net/forums/boat-design/new-age-trawler-motorsailer-kite-assisted-poweryacht-20319.html#post179946)

Sorry they both still have some diesel power. I think you might just have to have some of this for an ocean going vessel....at least for the next 10-15 years.

I want the vessel to make an ocean passage without ever having to fire up diesel engines and be crewed by only two to three people. When she is under power I'd like it to be electric motors running off batteries and solar power (with a diesel genset in reserve for emergencies).

I'll post pictures of the new size concept soon.[/QUOTE]

XHeeler

05-27-2009, 01:48 PM

is that a huge frontal wave could destroy your bridgedeck, as the force would be perpendicular to your windows and the overhanging flybridge and the water would have no place to go.

Maybe that is from watching too much "Deadliest Catch" over the weekend.

Becaris

05-28-2009, 12:19 AM

No doubt you are correct XHeeler :) However, some of these shots are just early concepts meant to provoke discussion and 'you shouldn't do that' comments. I have currently changed the design (and no doubt will do so several more times). Pictures of the current 'look' were included in a different discussion I posted about future hybrid technologies for a sailing cat. You can see them there if you care.

http://www.boatdesign.net/forums/boat-design/future-hybrid-catamaran-cruiser-27562.html

Becaris

07-24-2009, 07:38 PM

I've been playing with the concept design further. I've reworked the proportions and location of the cab to leave more hull distance forward. I've lowered the profile and slanted the cabin sides to make it more aerodynamic, particularly windward. There is a ten Kilowatt solar array (using existing dimensions for 315 watt panels). I've reduced the height of the sails to appropriate sizes based on the biplane rig (each mast now being 20m). The second set of solar panels sits on a raised hard canopy to give some extra deck space. The hull shape and depth are reworked to the dimensions of similar sized cats. The overall length of the yacht is now 20 meters.

So anyway, here are three pictures from the latest concept.

Spiv

07-25-2009, 08:15 AM

Becaris

07-25-2009, 11:32 AM

I'm not sure if you are suggesting less glass or not sloped. Less glass is certainly possible, but I've looked at too many professionally designed cats now to not use a more sloped cab for better performance.

Here is a link to just one such discussion:
http://www.multihull-maven.com/Upping_the_efficiency

As for the 'Targa' toward the stern causing issues in high winds, I did think of that, and I'm working out a system where this can be raised or lowered and 'locked down'. Notice that the roof space under the 'Targa' matches it almost exactly (it is slightly larger). And the struts line up so that they can insert below. This is so that when things are headed for extreme weather I can make it more streamlined.. Making a system that can raise and lower the Targa without adding too much weight is still a problem, mostly due to the weight of current solar panels. But I am hopeful (from reading about new advances in solar) that these panels will eventually be getting lighter. (Otherwise the entire 10 kwh array is a weight issue anyway).

I added a picture so show it in the lowered position.

apex1

07-25-2009, 04:57 PM

Becaris,
2 more topics for you to consider:

Sloping windows might 'look' aerodynamicand 'fast', but the reality of things is they turn a boat into a hothouse. A walk through any marina will reveal hundreds of boats with canvas covers over their slanted windows to stop the sun. the more you go into the tropics the more you will suffer, just for some 'look'. you will notice that many 'commercial' vessels have vertical or outward sloping windows like you had in the original fly-bridge. Commercial andnavy people actually stay at sea, they have the practical know-how.
The rear targa concept to have the extra solar array is good, however what will happen to it the first time the boat is caughtin 50kn wind (60, 70Kn)? perhaps someone with the knowledge can work out for you the force that such a large 'Sail' surfacewill exert.
I am not able to give you any technical advice, but I come from a long life at sea, had many boats, mostly catamarans and I look at things with a more practical and safety conscious eye.

Most valuable input!
The heat load under such windows will drive you nuts in the tropics (or even Florida, Med), the temp easily raises to 50° - 60 Celsius. One of the most successful range of Cat´s in the worlds charter fleets is the Lagoon series by Beneteau. Look them up and you know why!
The "Targa" will probably start to vibrate in heavy weather. But the idea of lowering it to house level is worth to be engineered thoroughly, I think.
A manually operated hydraulic can easily bear the load and doesnt cost the world.

Regards
Richard

Alik

07-25-2009, 10:28 PM

Here is our concept of 60' cat but with working solutions. Note the windows protected form direct sunlight, plenty of flat deck/cabin areas for easy moving around. Another feature is aft master cabin (size 4x4m) with sliding door that forms 'aft balcony'. Flybridge 5x5m provides good 360 degrees visibility form steering station and also is perfect place for crew and guests (they can enjoy seaview instead of looking at cabin bulkhead).

Spiv

07-26-2009, 03:55 AM

Alik,
very nice design, I can see you've put a lot of thought in it. Love that rear stateroom and the roof/ window lines.

Becaris,
unfortunately most of the so-called 'professionally designed' cats are designed for the ahestetics, rather than practicality as they need to please the uninformed masses.
Additionally some of them have never lived on a boat, trust me on that!
If they did, they would not suggest their future customers to have sloping windows.

apex1

07-26-2009, 07:29 AM

Nice boat Alik!

yipster

07-26-2009, 08:09 AM

Hi Spiv, did live for a while in the sun on a boat with sloped glas and blinds
(can even be canvas) outside over the glas takes much of the heat away

Alik

07-26-2009, 08:27 AM

Thanks guys, hope this J60 cat will be built one day, now construction is postponed due to crisis.

Unfortunately these days we have too much influence of car styling in boat design. Result - many boats are glamour toys for marina, not really designed for the sea. Sorry to say, but many boat owners are getting brainwashed with 'styling' and 'high-tech', however these are just marketing tricks having nothing common with performance, safety and comfort.

apex1

07-26-2009, 08:31 AM

>>>Result - many boats are glamour toys for marina, not really designed for the sea. Sorry to say, but many boat owners are getting brainwashed with 'styling' and 'high-tech', however these are just marketing tricks having nothing common with performance, safety and comfort.<<<

Unfortunately thats the plain truth.
Customers collect thousands of leaflets and brochures, calculate and discuss every tenth of a knot of performance,
and go to buy the "nicest".

Alik

07-26-2009, 08:48 AM

I always say that our customers are 'owners of second boat'. So those who owned boat before - they know exactly what they want and appreciate practical inputs in design.

Look at this cat - extremely practical and designed for performance and long stay on board. But some would call it 'shoe box' :) Yes, it is not a Ferrari!

apex1

07-26-2009, 09:21 AM

Well, I do´nt like it either! Verrry sorry Alik. But I am for sure not representative !
To the "owners of second boat" I tend more to say the seventh!

Alik

07-26-2009, 09:36 AM

That was North American style, they like it :) In construction now.

OK, this is another one, 32'. Cabin is sloped, looks sporty but volume of saloon suffer. This one is also in construction, hope to be on water in 2-3 months. We are working on 40' model now (slowly), same style.

apex1

07-26-2009, 09:57 AM

Well, this is more the taste of "average joe" here.
But the US people even buy Nordhavn´s. I would have a problem docking besides them.
But again, when it comes to individual taste of the average boatbuyer I am worlds away.

Spiv

07-26-2009, 10:37 AM

Alik,

The first boat is too narrow for good performance, but has got well thought superstructure.
The second's ratio is better.
Both have a flat bridgedeck, on planing cats it tends to slam a lot more than one like Bacari's, concept with double curves.
I have driven most power cats made in Australia, the best ride was given by the Manta (not in production now) with a wave braker going all the way and round half bridgedeck, like riding on velvet.
I also found that asimmetric chines (the interal are half way up the external) make it go up on the plane smoothly and break the force of incoming waves more gently.
Anyway, lets not hyjack this thread for too long....

Alik

07-26-2009, 11:04 AM

Alik,
The first boat is too narrow for good performance.

Actually is not, we have studied that using Molland's series. At speeds over 16 kts the interference of hulls is beneficial. The most unfavourable mode for this cat is 12 kts where resistance curve has a hump. Note that design speed of this cat is 21kts. Anyway, limitation of beam originated from Customer's request - they have some restrictions on mooring space.

Both have a flat bridgedeck, on planing cats it tends to slam a lot more than one like Bacari's, concept with double curves.

I own a planning powercat myself, with flat bridgedeck :) Planning cat lifts up and should not slam (on reasonable wave) if the bridgedeck is high enough - vertical clearance c should be 2-3% of length, so c=(0.02...0.03)L. Also should consider 'air cushion effect' in tunnel that reduces slamming. For overloaded cats with low bridgedeck - I agree, they slam, but this is not a case here.

Displacement cat needs c=(4...5)L. Displacement cat will start slamming on wave height h double of clearance c (h=2c). This was a guess that is confirmed by simulations and sea trials. So if we are talking about Aleut we should double 3' clearance - we get 6' wave!

I understand that some would prefer wedge in the tunnel. But in practice wedge is always lower than just flat tunnel. At least, flat and high bridgedeck is my preference.

Becaris

07-26-2009, 11:09 AM

Though Alik and his company have reasons to be proud of their boats and designs, this second one particularly is way off topic as it is not even a sail boat. The first one, a sailing cat of the same approximate length as my concept has some merit in this discussion from the windows standpoint and perhaps some of the layout. However, let's not lose track of what the concept is all about. In case you forgot (or didn't want to read), I'm working on the concept for a blue-water cruising sailing catamaran with these features:

1) Electric motor driven.
. a) Using new emerging technology batteries, lighter per watt stored.
. b) These batteries are charged by three methods:
... i While sailing running the motors in reverse
... ii From sun using 10 kwh solar array.
... iii From two windmill type generators.
... iv From a gen set running on diesel (last resort).
. c) In a pinch I'd also like the yacht to be capable of moving via electric motors running directly off the solar array (even if at slower speeds).
. d) Enough battery storage to power the yacht at about half max speed for a minimum of three hours (more would be nice).
2) Biplane style sails.
. a) These would use carbon fiber unstayed power rotating masts with fixed booms.
. b) Booms will be power self-furling on both of the twin main sails.

Objectives are simple:
1) As few ropes, pulleys, winches and stays as possible, none would be great.
2) As few different types of sails stored as possible.
3) Using the LEAST amount of diesel fuel as possible, none would be excellent.
4) Short hand sailing that requires the least amount of exposure on deck as possible.
5) Interior living space for eight people.
6) Power sufficient to run watermakers, air, electronics, etc. without budgeting.
7) Safety in redundant systems (including the mast, motors, etc.)
8) True positive buoyancy design (including the weight from all the 'stuff')
9) Efficient sailing design (hull shape, proper length to beam ratios, clearance above water, streamlined cab.

Things I don't care about:
1) Cost to build.
2) Cost to dock at marinas.
3) Sailing drawbacks of biplane rigs (everything has drawbacks, I know about the drawbacks of a biplane rig and want it for what I consider the positive sides. Others will no doubt disagree, they can build their own boat.)
4) The joy of sailing. (For me the sails are a means of cheap, self sustaining propulsion, nothing more. The catamaran over the mono hull is a means of avoiding constant 'tilt', and when designed properly, buoyant in case of capsize or hull damage).
5) The cost of diesel fuel and engines vs. the cost of an electric motor system (and all that comes with it. (I hate fuel docs, and will pay to avoid them at all costs) :)
6) Having to wait to start my build until the batteries and solar panel technologies reach the commercial market.

Anyway, those are the goals of this concept for a somewhat new blue-water cruising sailing catamaran, about 20 meters in length.

Alik

07-26-2009, 11:12 AM

For effect of BCB (beam between hulls CL) on resistance - pls see attached image. 'Base' is BCB=3.33m (case of Aleut), others are marked clearly. Prediction is done by Molland's catamaran series.

Alik

07-26-2009, 11:19 AM

1) Electric motor driven.
...
yacht at about half max speed for a minimum of three hours (more would be nice).

Electrical propulsion - is a marketing blurb, it does not work with today's level of technology for seagoing cat. Again, there is a lot of brainwash pressure on electrical propulsion, nice concept dream however :D

Becaris

07-26-2009, 11:24 AM

I'm not building today. This is a concept, and if you'll notice the last point in my 'I don't care about' section, is waiting for the technology to emerge. It is coming.

Alik

07-26-2009, 11:35 AM

I'm not building today. This is a concept, and if you'll notice the last point in my 'I don't care about' section, is waiting for the technology to emerge.
Sorry to say, but this means that Your concept has no value now :)

You can calculate windage drag of 22m cat, estimate power required to push it with head wind of 10-20kts (and wave!), and then check required electrical motor and batteries. Then, imagine the cat is passing strait of Singapore with its intensive traffic - how may hours of powering do You need, at what speed? ...

Without engineering side, such concepts are not worth any discussion.

Becaris

07-26-2009, 06:13 PM

Sorry to say, but this means that Your concept has no value now :)

You can calculate windage drag of 22m cat, estimate power required to push it with head wind of 10-20kts (and wave!), and then check required electrical motor and batteries. Then, imagine the cat is passing strait of Singapore with its intensive traffic - how may hours of powering do You need, at what speed? ...

Without engineering side, such concepts are not worth any discussion.

A concept may have no value to you. I, on the other hand, believe in planning ahead. I plan to build my yacht several years from now, with that in mind I was looking forward to talking to other designers about a future concept design. In case you're not familiar with a concept, it is usually done ahead of time, and a concept often explores ideas that are not currently available. Take a look at a concept car from any car company this year and you'll get the idea. If concepts had no value, then I'm pretty sure major companies would not waste their time. If you are interested in a thread about building a current cat, well, you can easily start one of your own, but telling me that a concept has no value... well, that's just silly, seriously.

However, as to your point about the strait of Singapore. Even projecting ahead to better batteries, which means more power storage in lighter weight, there will ALWAYS be a limit to how much stored battery power is available. What I plan for my yacht is sufficient battery storage for most of my motoring needs. I estimate that at about 3 hours or so off the two banks of batteries. If and when a rare situation arrives when I need to motor my sail boat longer than three hours, as stated above, I will turn on the Gen. Set and power the motors off diesel. I hope to not have to do this very often, but the option is always available.

Now, since you stated that you find this concept not worthy of discussion, that's certainly your prerogative. I did not see anywhere that you were required to post. This was a friendly concept discussion, nothing more. Attacking it is a waste of both our time.

apex1

07-26-2009, 07:43 PM

Now, since you stated that you find this concept not worthy of discussion,

Well Becaris THAT was not the statement! So, if you argue, argue about the complete statement. In this case that will be a bit difficult, yes?

Becaris

07-26-2009, 08:11 PM

Well Becaris THAT was not the statement! So, if you argue, argue about the complete statement. In this case that will be a bit difficult, yes?

As stated, I'm not here to argue with anyone, including you. If you have nothing constructive to add to this concept, I'm done speaking with you.

apex1

07-26-2009, 08:30 PM

The next arrogant bigmouth!
If you would have the ability to read, you would have noticed that I DID actually contribute to your premature dreams, and without the slightest sort of critic too! But you´re not looking for critical contribution, you´re looking for applause or fight!
Grow up! Then come back (they will have all the technique you need then! At least I guess so, `cos 20 years can change a lot)

Do they breed them in thousands at present?

Becaris

07-26-2009, 09:18 PM

Classy, now you have degenerated to name calling.

Becaris

07-26-2009, 09:28 PM

If anyone else would like to get back on topic, there WAS some discussion going on about the slanted windows being an issue in the tropics. There seems to be two things at odds here.

For example, in several of the Schionning catamaran designs there are a lot of aerodynamic slope to their cab, yet people have made good points that angled windows can add interior heat in the tropics. Is there a compromise? Like double pained glass, the exterior piece slanted for better performance into the wind and the interior piece of glass vertical? Trapping a layer of air between glass supposedly cuts down significantly on heat exchange. Comments? Suggestions? Some other option?

Alik

07-26-2009, 09:35 PM

Becaris, You see - simple boat operation question and You have no clear answer. For Your info, to feed motors from gensets direct will requre gensets of hundreds of kilowats (because this cat needs about 2x(100...150)HP for reliable propulsion)! This is possible, but we are not talking about fuel saving, weight saving and cost saving technologies anymore.

Unfortunately we have to deal with 'boatdreamers' with their futuristic-unrealistic concepts almost every day :) 'Electrical propulsion' is my favourite subject to argue.

Alik

07-26-2009, 09:45 PM

For example, in several of the Schionning catamaran designs there are a lot of aerodynamic slope to their cab
If You have been inside those cats, You would be surprised how small is the volume of saloon. Actually 50-footer with saloon of 35-footer... Also the headroom - 1.90m at the entrance point only, becoming 1.70m at galley and 1.50m at the stairways from saloon to the hulls.

Becaris

07-26-2009, 10:23 PM

I'm not here to defend Schionning. I'm only trying to decide if there is a way to get aerodynamic shape and keep the cab from heating up due to direct sunlight. You just seem bent on attacking things, now you are having a go at Schionning. Jeez.

As for your contention that you cannot build an electric powered cat, many 40' models are on the water and 60' models are currently under construction. Based on these actual yachts, I see no reason to change my mind on building an electric powered cat, particularly a couple years from now (though they are already being built now).

Alik

07-26-2009, 10:39 PM

I'm not here to defend Schionning. I'm only trying to decide if there is a way to get aerodynamic shape and keep the cab from heating up due to direct sunlight. You just seem bent on attacking things, now you are having a go at Schionning. Jeez.

I am not attacking Shionning's cats or anything else, just telling what I have studied from experience.

As for your contention that you cannot build an electric powered cat, many 40' models are on the water and 60' models are currently under construction. Based on these actual yachts, I see no reason to change my mind on building an electric powered cat, particularly a couple years from now (though they are already being built now).
OK, 40' is Lagoon - pls read the specs first. They can run 3 hours at 6 kts (calm water, no wind!). It will probably work for charter in Caribbean, but hardly enough for seagoing boat capable to withstand severe conditions.

Moreover, I have designed electrical powered boat also (8m, narrow hull), but that one was for the lake. For the sea, nothing is more reliable than marine diesel.

Becaris

07-26-2009, 11:19 PM

I don't actually disagree with your numbers on current electric powered yachts, but with the BILLIONS being spent on improving battery technology, with hundreds of companies competing to get there first, there is no doubt in my mind that in short order we will have a lot more power storage possible. You may not believe that will happen in that time, but I do and neither one of us knows for sure. I will continue with my concept of using electric power, it's my money and time, and I never count out new technology when this much money is at stake. If they were developing this for the yacht industry, I might agree with you, but not when car industries and fossil fuel companies are funding this research. So let's put this discussion to rest. You believe what you want, I will believe what I want.
I've made millions being a 'dreamer' and will never stop pushing the envelope with new concepts and ideas. As for the current 'concept' version model of this cat that I've posted, no doubt this is going to go through MAJOR changes before ever getting near a build. Just take a look at the early shots compared to the more recent ones. Night and day, and yet I know the concept will still go through more radical changes. This includes ALL systems as I will adapt to what is actually available as the time to build gets closer. Even then the concept will then go to a professional designer and engineer (neither of which I've ever claimed to be). It's just a concept to play with ideas at this point.

Alik

07-26-2009, 11:31 PM

Spiv

07-31-2009, 01:45 PM

Becaris,
we are continents apart, but we want the same thing.
I like your approach, 32 years ago I decided that one day I'd go round the world on my owh sailing boat. That boat was going to be a ferro cement monohull ketch! That is all I thought I'd ever be able to afford.
Time pass, things change, one learns.
10y ago I put for sale my last charter power cat with the intention to build a charter sailing cat, learn as much as possible about sailing cats, sell that and build my new home afloat.
This last boat was a 12.5m round shaped, slanted, aerodynamic looking boat, but I redisegned the superstructure to obtain more habitable space and less sun in the cabin. Pic attached.
I took that boat 3 times from Perth to Broome, 1600NM each way, treacherous coast the WA coast! Once got dismasted, fortunately the Carbon mast survived with little damage. But enough of my story.

I too am designing my new boat, but I am nearly finished, my critical points are:
As big as I believe I can handle on my own,
space for two 90% of the time, for 6 10% of the time,
as little rigging as possible,
self sufficent
Ability to go under low bridges, up shallow creeks and dry out,
at anchor 90% of time, under sail the rest of the time (motoring only when necessary)
redundancy on all systems
safety: 1st
comfor: 2nd
speed: 3rd
cost: 4th
what other think of it: unimportantIn answer to #1&2 above I ended up with the internal habitable volume of a 14m cat, but for 8, 9 & 10, I stretched the hulls to 17m.

For #3: three furling sails, two self tacking and a traditional reacher

For #4: solar, wind energy, heating/ cooling, diesel genset(s)

For #5: lowerable mast, daggerboard and retractable rudders, beaching mini-mini keels.

For #6: big anchors :D, efficient, easy to reduce or increase sails, electric motors ?? (still looking here as i want the equivalent of 2x40~50HP)

For #7: I'll have two of everything + contingency plans/ backups.

For #8, 9 & 10: I asked an experienced cat designer to design 17m long slender hulls with 1.1m bridgedeck clearance.

For #11: I am working harder :rolleyes::rolleyes:

For #12: not loosing any sleep :P

I'd be happy to share with you any of my thoughts, if you ask.
I am very interested in learning more about diesel electric hybrid; I have read all I could find on the web + there are a few threads on this forum on the subject. Some very interested people and some skeptics.
I'd like to hear from you what you found on the subject.

Becaris

07-31-2009, 04:55 PM

We're not as far apart as you might think. Here is your list and mine compared:

1. As big as I believe I can handle on my own
A: Same, accept said, 'must be able to sail by myself, though that's not likely.'
2. space for two 90% of the time, for 6 10% of the time.
A: Space for four 90% of the time, for 8 10% of the time.
3. as little rigging as possible.
A: same
4. self sufficient
A: same
5. Ability to go under low bridges, up shallow creeks and dry out.
A: same, though my yacht (for passenger average reasons) will be larger and therefore I'm not going up quite as small a creek :)
6. at anchor 90% of time, under sail the rest of the time (motoring only when necessary)
A: at anchor 60% of time, under sail the rest of the time (motoring only when necessary) I'm planning on doing a lot of travel.
7. redundancy on all systems
A: same
8. safety: 1st
A: same
9. comfor: 2nd
A: same
10. speed: 3rd
A: same
11. cost: 4th
A: same
12. what other think of it: unimportant
A: same

As for diesel electric, regardless of the nay sayers, there is a lot to be excited about in going with electric propulsion. First off, comparing just horse power is not the best measurement. Torque is of much more interest. There is a lot of interesting information on that (and running larger props than diesels etc.).

Another feature of going electric that I like is that my fuel station is wherever I currently am, moving or not. With sailing (motor sailing), solar and (boat stationary) wind power generation on board, it's a rare time that I won't be able to replenish 'fuel' (batteries). I can run out of power, but I can refuel just about anywhere anytime. Run out of diesel away from a fuel station and I doubt you have a refinery on board. There is also just the noise and smell improvements. I'd post some links to info on electric propulsion, but you have probably found the same ones (just google electric yacht propulsion).

On a different subject, one of the reasons I'm looking into a biplane rig is so that I can design a system to lower the masts so I can go up rivers and get under bridges. With a 20m length, a single mast was pretty large and heavy to deal with, but by going with a bi-plane, each mast becomes smaller for me to deal with. There are still issues with this, but I'm in contact with some carbon fiber mast makers and they are surprisingly light to handle when kept to a reasonable length.

My issues to deal with are that I want power rotating masts, and I also want to be able to lower them myself. It's an interesting design challenge. There are other reasons I'm leaning toward a bi-plane rig as well. Redundant masts isn't a bad thing from a safety aspect. Mounting the masts in the hulls works out well for layout and strength. And no stays or cables since there is no jib. Just two power rotating masts with self furling booms. I should be able to reef and trim the sails without dealing with ropes and winches, or going out on deck with the weather up. Of course, I'll pay for those luxuries in other areas, but I can live with the small drawbacks.

I'd love to hear your, or anyone else's suggestions on how to achieve some of these goals. I'm also interested in your project and progress and would love to hear more as you move forward.

Alik

08-01-2009, 12:03 AM

First off, comparing just horse power is not the best measurement. Torque is of much more interest.

Nonsence!

There is a lot of interesting information on that...

... in advertisement booklets and publications.

apex1

08-01-2009, 01:07 AM

Becaris
do´nt believe everything you read, do it like me, believe what you know!
And search for the Nigel Calser articles on hybrid propulsion in "Professional Boatbuilder" that brightens your view. If you cannot find them, I will post them on Monday. Or become a professional boatbuilder then you do´nt need to read them.

Alik

08-01-2009, 01:29 AM

apex1

08-01-2009, 01:51 AM

apex1:
Yes, this one is good reading for those who believe in 'perpetum mobile' yacht propulsion: :)

Professinal Boatbuilder #109-2007, p.140-154:
http://www.proboat-digital.com/proboat/20071011/
Conclusions on p.150.

Thank you Alik, saves me looking it up. I´m delivering a boat, well shakedown run to tell the truth. Every second hr another sh.t. Every second hr another mail conversation and argueing. Ahhhhh boatbuilding is fun..

Alik

08-01-2009, 02:22 AM

I´m delivering a boat...

Good luck, and post some photos!

Becaris

08-01-2009, 12:02 PM

It’s sometimes amazing how one person reads an article and sees one thing due to their preconceived ideas, and then someone else reads the same article and sees something different. I read your article (with my own preconceived ideas) and find nothing that deters me from considering a hybrid electrical propulsion system.

First off, you pointed to his conclusion on page 150. Let’s be clear, his conclusion states that the author had intended to purchase, and I quote, ‘a full-dress serial system’. This is what he is comparing to diesel engine technology in his conclusion. At the beginning of his article he defines this as different from a hybrid electrical system. A serial system (according to the author) runs off a generator all the time, where the hybrid runs off of the batteries. His contention is that with current battery technology (in 2007 when this article was written) a hybrid system does not have efficient enough batteries. There is too much weight to have enough power storage. This is why he was looking at a serial system. He also states in this article, and I quote,

“After years of being promised radical changes in battery technology, we may be on the verge of a revolution that will change the rules for designing DC systems for boats”.

Given that two years later we do have better batteries that store more energy at less weight than when he wrote this article (lithium for one), and even more interesting battery technology on the horizon, a hybrid electrical system is becoming increasingly attractive (and this author does not disagree).

He notes, and I quote,

“There is an obvious trade-off here between battery size, weight, expense, and available propulsion time. Even a fairly limited battery capacity provides instant propulsion power (helpful in an emergency), plus the ability to conduct brief maneuvers without cranking an engine.”

Coupled with the better battery technology now available, these trade-offs are tilting more and more in favor of hybrid electrical propulsion.
Even two years ago when he wrote this article, he noted that, and again I quote,

“On boats that sail enough to regenerate a considerable part of the energy needed for propulsion, regeneration is clearly attractive.”

I will be one of those usage patterns, and therefore, electric propulsion is very attractive.

This article definitely keeps my interest in the electric propulsion system, thanks for pointing it out. As I’ve stated all along, and backed up by this author, with more efficient lighter batteries (which already exist since this was written) a hybrid electrical propulsion system becomes quite attractive with lots of nice advantages. The author goes into some of these, including, and again I quote,

“Electric motors develop full torque at any speed, down to 0 rpm. In conventional (diesel engine) propulsion installations, the idle speed of the engine will be between 700 rpm and 1,000 rpm.”

Thus you now understand my comment in an earlier post about torque. With a hybrid electrical system I will use larger props than a diesel engine installation because I have use of torque at low rpms, and can therefore move more water without having to turn a smaller prop at higher speeds. This is backed up by the author in the article you quoted.

In conclusion, based on this article and lighter weight battery storage, hybrid electrical propulsion is getting more and more attractive.

Alik

08-01-2009, 12:52 PM

On boats that sail enough to regenerate a considerable part of the energy needed for propulsion, regeneration is clearly attractive.”

Ok, quote it in full:
'But this is not the usage pattern of most of recreational boats
...
has restricted regenetative propulsion to a small niche market'.

With a hybrid electrical system I will use larger props than a diesel engine installation because I have use of torque at low rpms, and can therefore move more water without having to turn a smaller prop at higher speeds.

Nonsence #2, get the basics before we can discuss it.

Alik

08-01-2009, 01:11 PM

First off, you pointed to his conclusion on page 150. Let’s be clear, his conclusion states that the author had intended to purchase, and I quote, ‘a full-dress serial system’. This is what he is comparing to diesel engine technology in his conclusion. At the beginning of his article he defines this as different from a hybrid electrical system. A serial system (according to the author) runs off a generator all the time, where the hybrid runs off of the batteries. His contention is that with current battery technology (in 2007 when this article was written) a hybrid system does not have efficient enough batteries. There is too much weight to have enough power storage. This is why he was looking at a serial system.

And this is what You have said before:
If and when a rare situation arrives when I need to motor my sail boat longer than three hours, as stated above, I will turn on the Gen
So You run electrical motors from generator, or You have no clear idea how? :) If You do so, it is a 'serial' system.

Alik

08-01-2009, 01:49 PM

I have done quick estimate for one of our designs - 60' catamaran with twin 75HP engines. For propeller diameters from 0.4 to 2.8m we found optimum RPM and corresponding speed. There are few conclusions (they are evident):

- After certain limit, there is no advantage of increasing prop diameter and reduction of RPM;
- Propeller diameter is limited by draft of boat; 60' sailing cat with draft of 1.06m (fully loaded) is likely to have prop diameter limit of about 0.6m.

Calculation result, using multiple speeds for optimum RPM
Propeller data
Blades :3
Diameter :0.400 Metres
Pitch :0.381 Metres
BAR :0.800
Efficiency :50.1

Engine data
Number :2
Power :55.000 kW
RPM :1690.729
Reduction :1.000
Shaft RPM :1690.729
Shaft torque :0.3106 kN.m

Vessel data
Speed :10.7 Knots
Thrust/shaft :4.838 kN

Calculation result, using multiple speeds for optimum RPM
Propeller data
Blades :3
Diameter :0.800 Metres
Pitch :1.107 Metres
BAR :0.800
Efficiency :68.1

Engine data
Number :2
Power :55.000 kW
RPM :481.718
Reduction :1.000
Shaft RPM :481.718
Shaft torque :1.0903 kN.m

Vessel data
Speed :11.8 Knots
Thrust/shaft :5.939 kN

Calculation result, using multiple speeds for optimum RPM
Propeller data
Blades :3
Diameter :1.200 Metres
Pitch :1.663 Metres
BAR :0.800
Efficiency :72.6

Engine data
Number :2
Power :55.000 kW
RPM :281.430
Reduction :1.000
Shaft RPM :281.430
Shaft torque :1.8662 kN.m

Vessel data
Speed :12.1 Knots
Thrust/shaft :6.166 kN

Calculation result, using multiple speeds for optimum RPM
Propeller data
Blades :3
Diameter :1.600 Metres
Pitch :2.228 Metres
BAR :0.800
Efficiency :72.0

Engine data
Number :2
Power :55.000 kW
RPM :193.656
Reduction :1.000
Shaft RPM :193.656
Shaft torque :2.7121 kN.m

Vessel data
Speed :12.1 Knots
Thrust/shaft :6.143 kN

Calculation result, using multiple speeds for optimum RPM
Propeller data
Blades :3
Diameter :2.000 Metres
Pitch :2.779 Metres
BAR :0.800
Efficiency :67.9

Engine data
Number :2
Power :55.000 kW
RPM :144.990
Reduction :1.000
Shaft RPM :144.990
Shaft torque :3.6224 kN.m

Vessel data
Speed :11.8 Knots
Thrust/shaft :5.931 kN

Calculation result, using multiple speeds for optimum RPM
Propeller data
Blades :3
Diameter :2.400 Metres
Pitch :3.325 Metres
BAR :0.800
Efficiency :61.9

Engine data
Number :2
Power :55.000 kW
RPM :114.195
Reduction :1.000
Shaft RPM :114.195
Shaft torque :4.5992 kN.m

Vessel data
Speed :11.4 Knots
Thrust/shaft :5.590 kN

Calculation result, using multiple speeds for optimum RPM
Propeller data
Blades :3
Diameter :2.800 Metres
Pitch :3.771 Metres
BAR :0.800
Efficiency :52.7

Engine data
Number :2
Power :55.000 kW
RPM :93.775
Reduction :1.000
Shaft RPM :93.775
Shaft torque :5.6008 kN.m

Vessel data
Speed :10.8 Knots
Thrust/shaft :5.010 kN

Becaris

08-01-2009, 04:53 PM

Alik, Yes, I said in 'rare' situations.

This is what the word 'rare' means. It is a word as opposed to normal operation, or 'the majority of the time'. So, if during a rare time I must motor more than three hours, and there is an efficiency loss compared to diesel during that RARE time, I can live with it for all the benefits I feel I am gaining the majority of the time as a hybrid operation.

You have never explained to me how I'm supposed to refuel those diesel engines you love so much once I'm out of fuel and no where near a dock. Hmmm. Or... how to avoid those fumes, or that noise? These are important points to me, ones that you cannot challenge with a diesel propulsion system.

As for your comment of 'the whole quote', I said, clearly, that I will be one of those usage patterns, and therefore, electric propulsion is very attractive. In other words, since you didn't get it, my patterns will NOT be recreational usage .

Finally, this is a thread about my project, not yours. I've stated clearly to you multiple times now that we will have to agree to disagree when it comes to the propulsion system I will likely choose for MY boat. Do you see me coming to your project and trying to argue with you about your choices? Finally, do you really believe you are going to convince me to use diesel over electrical propulsion at this point, or are you just barking up the wrong tree? Good luck with that.

brian eiland

08-02-2009, 01:09 AM

It’s sometimes amazing how one person reads an article and sees one thing due to their preconceived ideas, and then someone else reads the same article and sees something different.
I will have to go back and re-read that article again myself (likely several times, to absorb it all), but if I recall the jest of it Nigel was being candidly honest about the somewhat over-hyped new diesel-electric systems for small craft. He is obviously a fan of the concepts, but he is not going to over-sell the ideas at this point of time.

I really appreciate Nigel Calder's thorough anaylsis of these subjects in his series of articles....and his honest conclusions that I'm sure he wishes were more positive.

I saw another short summation he did on wind generators on boats, and it did not look encouraging at all. I'll see if I can remember where I saw it.

As the Chinese say we live in interesting times, and it will be interesting to see the many new developments that our limiting supply of petroleum fuels forces us into. Too bad we have to battle such a poor economy with its restrictive development funds at this same time.

Alik

08-02-2009, 01:48 AM

As to the use of boat, believe me that 99% of 'boatdreamers' dream of long ocean passages, but end up sitting in marina most of time with short trips to nearest island. This is well proven by statistics :D

Finally, this is a thread about my project, not yours. I've stated clearly to you multiple times now that we will have to agree to disagree when it comes to the propulsion system I will likely choose for MY boat. Do you see me coming to your project and trying to argue with you about your choices? Finally, do you really believe you are going to convince me to use diesel over electrical propulsion at this point, or are you just barking up the wrong tree? Good luck with that.

Don't You think critics benefit Your concept more than just applause? :) If not, just put Your concept on the wall of Your room, don't put it in public forum... :D

Spiv

08-02-2009, 03:12 AM

Becaris,
when I said continents away, I meant phisically, not ideologically (USA-AU).

My last single mast was 17.5m tall, two guys could move it around the yard on their shoulders. With spreaders, s/s wires atc we astimated it was 250~280kg.
The pictures attached show how I used to lower it. An electric winch would do the job in 45~50 seconds. Set up time (from Sailing) before and after about 10min.
The poles for the A frame could be used as (oversised) spinnaker poles.
With the frame up I could go under 6.5m bridges, with the mast flat on the roof and the frame down, 3.8m.
I designrd the system looking at what others had done and using more that une good idea together.
If you cannot lower your mast, you miss the beauty of Perth.

In my new boat I seeked to solve a few problem I had with the Marconi rig:
Mainsail,I dislike more than any other piece of sailing development. You see, my old boat woulg go very well with the jib only, while the main was just a real pain. Granted, not all boats behave the same, nevertheless there are also several other reasons I don't want a conventional main with boom. See my and Brian Eiland 'mainless' forum threads.
Unless you have dozens of wires, if you loose one stay, you loose the mast (happened to me)
The lee shroud is always slack. If you overtighten the rig in a cat you risk serious structural damage.
When you release the forestay (or the backstay) to lower the mast, the mast becomes very unstable and waves or power boats can cause distress or even damage.The solution that fits me best is the "A" frame with 3 furling sails. Like i said two will be selt tacking.
This way I will have an infinite range of sail area for all situations.
Some people say: "yea, but you'll loose speed, pointing ability bla bla".
well I have enough 'practical' experience to know that they are wrong, in any case I don't care and I have no intention to beat around the world to windwards!!
I'll show you some drawing later.

Spiv

08-02-2009, 03:33 AM

As far as Nigel Calder, he is very much PRO diesel this from the European Union hybrid-electric drive project site (http://www.electricmarinepropulsion.org/Pages/NewsFrom_EU-HYMAR.html):

"Calder brainchild
HYMAR is the brainchild of Nigel Calder, boating journalist and marine electrical systems expert. He wrote the funding proposal with assistance from Ken Wittamore of EURMIG. "

and:

"EU partners
European partners in the HYMAR project are Bosch Engineering - Germany, Malo Yachts - Sweden, Steyr Motors - Austria, Victron Energy - The Netherlands, Bruntons Propellers - UK, Enersys - UK and INSEAN (L'Istituto nazionale per studi ed esperienze di architettura navale) - Italy.
EMP will participate through a newly established European firm, E motion Special Projects (ESP), headquartered in Plymouth, UK, with research facilities in Bordeaux, France, near CNB-Lagoon."

In San Carlos, Ca, the Telsa Roadster (http://www.teslamotors.com/)does 0 to 60MPH in 3.9 sec and can drive for up to 244M on thousands of little richargeable Lithium batteries connected in series (laptop like).
So, good things are coming from all different angles of the globe.

And, this (http://www.youtube.com/watch?v=BrHXdM9f13k)street legal electric drag racing car holds the world record!!
Guess what: it's all to do with TORQUE.

The future in near!

Alik

08-02-2009, 04:35 AM

2Spiv
http://www.electricmarinepropulsion.org/Pages/Technology_hptorque.html
This is good sample of promotional publication!

Because both horsepower and torque in a diesel drop sharply at low rpm, the propeller turned by a diesel engine must be undersized. A large prop that a diesel would in theory have enough torque to turn at high rpm would stall the engine at low rpm, when the torque is much less. And of course, below a diesel's idle speed, typically from 600-1,000 rpm, torque and horsepower disappear completely because the engine stops running.
Why are they talking about running diesel at idle speed??? Is there any practical use of running engine at idle speed?

That doesn't happen with E motion electric motors. Their torque curve is flat. Torque doesn't drop off at low rpm, and there's no minimum idle speed. An E motion motor spins as slowly as you want it to and still turns as big a prop as it can at its maximum speed of 1,000 rpm
OK, how big can be the prop? 1m, 1.5m or 2m? How to fit this prop in the boat? (see my calculation posted before). If we are talking about common propeller with its diameter limited by boat's draft, there is absolutely no problem to power it from diesel.

Definitely there are some advantages of electrical propulsion for certain types of boats for certian applications (big displacement boats with considerable housing loads, trawlers and tugs, etc. - those are used for decades already!). But there are a lot of disadvantages also, lower reliability is the biggest issue.

apex1

08-02-2009, 07:15 AM

Spiv
>>>>As far as Nigel Calder, he is very much PRO diesel <<<<

How can one be named biased when he was building his own yacht to become a test platform for a hybrid system? (And a Bus system too).
Calders results by so far are pretty clear and his statements are the best proven in his (most common) size of sailing yachts.
The "Tesla Roadster" btw was not a good example, car applications are worlds away from marine systems.

Alik
>>>>believe me that 99% of 'boatdreamers' dream of long ocean passages, but end up sitting in marina most of time with short trips to nearest island<<<<

Absolutely true! As is the size of the boat premature dreams create. ALL are dreaming too large to be affordable or sensible.

And why does it happen here on every second thread that the amateur calls the professional biased?

I know the answer, and I´m sure when I say how it is, we have the next fight here with all the premature statements about ones integrity, education and skills.
But I do!

Almost every amateur "boat dreamer" opening a thread here is looking for a confirmation of his dreams and applause, not for a critical scrutinizing or constructive critics or denials. And because they are not willing to leave their point of view and follow good advice they ALL end up having no boat! As long as I contribute to this Forum there was not a single one of these "dream designers"** coming to a point where building (of a then mature design) took place! NOT A SINGLE ONE !!!!
** a pretty bold claim btw. none of them was able to "design" a vessel, not one....

So, do we waste our time here?
Sometimes yes, when the stubborn kid starts fighting with the pro´s.
Usually not, when we can provide enough valid advice in general, to let other readers have a profit of the thread.

Regards
Richard

Alik

08-02-2009, 08:13 AM

when we can provide enough valid advice in general, to let other readers have a profit of the thread.

That's a good point, however sometimes these posts are getting lost among boatdreamers' insinuations :)

yipster

08-02-2009, 08:16 AM

like to hear you experts opinion on steyr's integrated solution

STARTER MODE
In Starter Mode, the combustion engine can be started with the
electric motor. The conventional starter motor can be eliminated
or will remain redundant.
GENERATOR MODE
In Generator Mode, the extended battery pack is optimised and
charged.
ELECTRIC CRUISE MODE
In Electric Cruise Mode, the boat is driven purely by the electric
motor. The battery pack is constantly monitored on its state of
charge and battery condition. This is brought to the attention
of the driver through the STEYR CONTROL CENTER (SCC).
BOOST MODE
In the lower speed range, depending on dynamic requirements
of the driver and the battery condition, the Boost Mode is used
and the combustion engine is then supported by the massive
torque of the electric motor. The e-motor supports the coupling
and decoupling of the combustion engine. An improved response
of the drive unit occurs through the boost mode.

http://steyr-motors.com/products/pdf/hybrid.pdf
http://www.steyr-motors.com/products/images/ifg.pdf
http://www.steyr-motors.com/products/pdf/ifgpower.pdf

Alik

08-02-2009, 08:28 AM

2yipster:
This looks promising, becasue they have diesel always available for backup!

If they deliver 7kW from each electrical motor, probably they can run about 6kts on 40' cat in calm weather.

apex1

08-02-2009, 08:34 AM

Hi Yipster
Mature concept and proven in the scale it was invented for (developed of course).

yipster

08-02-2009, 08:50 AM

yes yes, thougt it sounded good, thanks for opinions!

Spiv

08-02-2009, 09:37 AM

Alik;
"This is good sample of promotional publication!"
Agree, they want to sell their stuff, so one must read with caution, however the fact is that a directly coupled diesel/ prop engine has some drawbacks to a diesel/ electric drive.

Trains are driven by diesel-electric, the AU navy is spending several billions on diesel electric ships.
Why do submarines and tugs have been using them for decades?.... I could go on for half an hour with examples.

Clearly electric motors have an advantage. Now, one must create the electricity, here is where diesel are good: run them at constant rpm and charge batteries. No gearboxes, no prop-shafts.
If you have enough stored electricity you don't need to start your diesel, if not then you start it. To me it's the best outcome.
Yes, more expensive, but I can live with it.
Lastly, you can place the diesel and the motors anywhere on the boat, for instance the motors could be placed out of the boat, even on the side (bridgedeck side in a cat) rather than under the hull, hence no more running aground problem; in most cases, one would be able to pull himself out of a grounding.

Apex1,
"Almost every amateur "boat dreamer" opening a thread here is looking for a confirmation of his dreams and applause, not for a critical scrutinizing or constructive critics or denials."

Not true, I have seen Becaris changing his design and evolving it, and others on other threads too.
I also have owned boats designed by "Professionals" that turned out to be real dogs. The ocean bed is full of sunken boats designed by "Professionals" that have lost their keel and sunk as well as boats built by sub-standards "professional" boat yards.
So the argument can be easily turned around: how many "professional" designers actually go to sea to understand that what they promote doesn't actually work out there?
How many heavy catamaran with low bridgedeck are sold to naive prospective sailors to eventually regret their purchase?

How many flat bottomed monos are still designed to 'beat the rule' and bounce from wave to wave till they develop some fatigue and fail?

On this forum, a real "Professional" should be able to give advice without cutting with a knife.
Bot you and Alik must learn to give advice without cutting if you want to earn the label of "Professional".

Alik

08-02-2009, 10:00 AM

apex1

08-02-2009, 10:53 AM

Bot you and Alik must learn to give advice without cutting if you want to earn the label of "Professional".

I did know it happens, thank you for proving me right!
And the amateurs then are "granting" us professionals the label of professionalism?

You are right that Becaris has changed his sketches (there is no design), but he did never leave his preconception and still makes wrong claims or statements. (As you too btw.)

Richard

Becaris

08-02-2009, 11:35 AM

Your ridiculous claims of my seeking 'praise' are unfounded and just plain rude, as are most of your comments. You obviously have no conception of what I am seeking in posting these concept models (not sketches, if you're going to correct someone). I'll spell it out for you, I have posted a concept for the future. The idea in a post like this is to have others help with positive suggestions to develop and evolve new ideas. Of course there are issues and problems with any concept, particularly one this radical. But that's what concepts are for, radical ideas.

It's often called 'Blue Sky Development'. If you are not familiar with the term it means that at this stage of development you put out any idea and then take a look to see how you could manage it, or if it leads to some other idea. What you don't do in Blue Sky development is stick your head in the sand and close your mind to new ideas, yelling, 'It can't be done, you are stupid! We must always do it the way it was done before!"

I am CEO of two companies, both of which design new products. If any of my engineers ever walked into a design meeting with the rude and negative behavior that Alik has demonstrated I'd fire them on the spot. The term 'professional' has a lot more to it than the ability to spout numbers and ridicule ideas.

If I was here to just seek praise, do you think I would have taken any suggestions by anyone and changed the model? (Which, if you read, you will see that I have done).

<removed personal attack>

apex1

08-02-2009, 12:00 PM

[QUOTE] I'll spell it out for you, I have posted a concept for the future.

A bold statement, hear, hear. Others are after the same concept since ages, and we encourage them to go on. They do it professional....

The idea in a post like this is to have others help with positive suggestions to develop and evolve new ideas. Of course there are issues and problems with any concept, particularly one this radical.

NO that is seeking for applause!

The term 'professional' has a lot more to it than the ability to spout numbers and ridicule ideas.

You can hardly imagine how right you are here!!!

If you would be the person you claim to be, and if you would be as familiar with professional developments, as you claim (and I am), you would know that in early stages of developing phantasies into concepts one thing is absolutely forbidden: to say anything positive about the idea!!! Only, and exclusively, constructive critics are allowed to bring a given idea further towards a doable scale.

I must confess, not all the critics deployed here have been of the constructive sort. But not all of your attempts have been either.

And a last word to your professionalism: bear in mind that not all of the contributors here are native English speakers, it makes little sense to show haircutting attitudes (and is unprofessional) when there is a term not convenient for you! And if you like, call your sketches models, they remain to be worlds away from design!

I flaged this post to moderator, personal attacks are unacceptable.

correct! Did I say it will turn this way? Laymen never resist to attack pro´s when the ballon bursts.

my
Regards
Richard

Becaris

08-03-2009, 01:15 PM

I like how you run to the moderators when you are called unprofessional, yet think nothing of a personal attack calling someone, and I quote, "Bigmouth".

Well, not to worry, as I stated, I am done with all your attacks and will not be returning to read this nonsense any further. I have more important things to do than waste my time reading your unhelpful comments. Attack me all you like, I won't be reading any more of your negative posts anyway.

sailsocal

08-16-2009, 01:15 AM

Now that the fighting is over, maybe we can get back to some interesting discussion about electric boats!

The main problem with battery technology is that the energy density is too low -- they just don't store enough energy for the weight/volume. But Becaris and I agree that this technology is moving quickly and should allow for some great new design possibilities in the coming years. It will be a huge step forward when there is no longer a need for diesel engines with their noise, pollution, and maintenance problems. Fuel system, oil system, cooling system, transmission, and hundreds of moving parts, all to be replaced by a simple direct electric drive with one moving part (armature/prop shaft).

One company called PolyPlus is promoting their new technology which could drastically improve the battery capacity. The lithium batteries commonly used in consumer devices and electric vehicles today have an energy density of around 100 Wh/kg. PolyPlus claims:

"Polyplus is developing Li-Sulfur, Li-Air, and Li-Seawater batteries based on protected
Li electrodes. The projected energy density and specific energy for Li-Air batteries is on
the order of 1000 Wh/l and 1000 Wh/kg. PolyPlus intends first to commercialize primary
Li-Air batteries followed by the introduction of secondary Li-Air chemistry. The Li-Seawater
battery is a primary battery system intended for marine applications. The theoretical
energy desity for Li-Seawater is 9000 Wh/kg and 4900 Wh/l, and PolyPlus expects to
deliver cells with practical energy densities of 4000 Wh/kg and 2000 Wh/l."

Sure it's only a press release, but even if the new technology delivers only HALF what they claim it will be a breakthrough. If we had batteries with 9000 Wh/kg, would we even need sail power at all? Probably just as backup for long-distance cruising.

Gilbert

08-16-2009, 12:05 PM

Just thought I'd mention that the word professional only means that you are paid to do what you do. Period. It doesn't mean any more than that.

apex1

08-16-2009, 01:31 PM

Just thought I'd mention that the word professional only means that you are paid to do what you do. Period. It doesn't mean any more than that.

Jahhh Gilbert, it does not mean specialist, technician, person skilled in the art, expert, practitioner, skilled, correct, occupational, vocational

BTW most real professionals do not get paid, they are well established self employed.

Regards
Richard

Richard Woods

08-16-2009, 01:31 PM

Agreed. A "professional" boatbuilder may be a 16 year old school leaver who is earning money to buy a motorbike. That is why many production boats are designed to be built very simply. Many home builders build a much better boat.

A "professional" could also be defined as someone with integrity, ie someone who believes in certain values and sticks to them, even if the customer wants otherwise.

Richard Woods of Woods Designs

www.sailingcatamarans.com

apex1

08-16-2009, 01:35 PM

Agreed. A "professional" boatbuilder may be a 16 year old school leaver who is earning money to buy a motorbike. That is why many production boats are designed to be built very simply. Many home builders build a much better boat.
A "professional" could also be defined as someone with integrity, ie someone who believes in certain values and sticks to them, even if the customer wants otherwise.

Fully concur!

Alik

08-16-2009, 02:06 PM

Another important feature of professional is level of responsibility for his technical decisions and designs.

Gilbert

08-18-2009, 10:12 AM

Just in case some don't catch on to what I was implying when I said the word professional means only that you are paid to do what you do, I will clarify a bit.
Being an amatuer or hobbyist does not necessarily imply that you are not a specialist, Technician, person skilled in the art, expert, skilled or correct. It just means you are not paid to do it.

Spiv

08-19-2009, 05:03 AM

I talk for myself, but I am sure Bacaris has had enough of this.
Let's all just stick to the thread "22m Cruising Cat Concept", please

brian eiland

08-19-2009, 11:11 AM

like to hear you experts opinion on steyr's integrated solution
I've had an interest in this Steyr concept for a few years myself:
http://www.boatdesign.net/forums/diesel-engines/steyr-16943-2.html#post149942

There was an interesting point made by someone about 'servicing' such an electronic device coupled in line with the drive train....you might have to 'pull' the main engine to get at some problem with the 'generator'.

brian eiland

08-19-2009, 11:14 AM

Why are they talking about running diesel at idle speed??? Is there any practical use of running engine at idle speed?
Lots of sportfishers run around a great majority of the day at virtually idle speed.

Alik

08-19-2009, 11:37 AM

Lots of sportfishers run around a great majority of the day at virtually idle speed.

For that, trolling mode at gearbox is available, or separate trolling outboard...

brian eiland

08-19-2009, 11:39 AM

Granted there has been a lot of 'overselling' of this relatively new subject in smaller yacht applications.

But I for one do believe it is the future, particularly in auto applications. And as it is refined there, the trickle-down effect will arise, and boats will benefit as well. The torque characteristics of the electric motor just match needs of a vehicle propulsion device too well to be ignored...max torque at low speed acceleration, verses the exact opposite supply from an internal combustion engine.

Now we just have to solve the energy storage equation in general, and the electrical energy storage in particular.
http://www.boatdesign.net/forums/propulsion/new-propulsion-sytems-ships-9630-14.html#post89605
http://www.boatdesign.net/forums/propulsion/new-propulsion-sytems-ships-9630-11.html#post85848

brian eiland

08-19-2009, 11:48 AM

For that, trolling mode at gearbox is available, or separate trolling outboard...
I've seen more than a few twin 1000-2000HP diesel sportfishers (that don't have 'outboards') idle those big engines for hours at a time :!: ...can't be good for those engines either.
http://www.runningtideyachts.com/archives/needforspeed.html

Alik

08-19-2009, 11:51 AM

I've seen more than a few twin 1000-2000HP diesel sportfishers (that don't have 'outboards') idle those big engines for hours at a time :!: ...can't be good for those engines either.
http://www.runningtideyachts.com/archives/needforspeed.html

Trolling valve is the solution.

apex1

08-19-2009, 11:56 AM

Trolling valve is the solution.

But that is again wasting energy Alik. The solution would be...............nah I will not say it again.....;)

Alik

08-19-2009, 12:09 PM

But that is again wasting energy Alik. The solution would be...............nah I will not say it again.....;)

True, that is why separate trolling motor is better. This solution with electrical or gasoline trolling outboard is used for decades already...

Spiv

08-22-2009, 12:05 PM

This from the magazine:

Colleague, To sign up for your own FREE digital copies of Renewable Energy Focus (http://mail.elsevier-alerts.com/go.asp?/bEEA001/mRS6029/q0JFI29/u0RDJ5/xV44S29), simply go to: www.subscription.co.uk/cc/ref/2192 (http://mail.elsevier-alerts.com/go.asp?/bEEA001/mRS6029/qRAOI29/u0RDJ5/xV44S29) and complete the online registration form.

There is always something interesting about solar and batteries in it.

Jameswright4

09-06-2009, 05:28 PM

Well shall we try and make this a reality ?

I am the owner of the last Walker Wingsail built and in the nine years of ownership have rebuilt Larinka and can safely say the Wingsail works perfectly . The higher the winds speed the better she performs. Anything over 30 knots and we feather the wing and highest endurance was 65mph and she remained stable despite a massive sea.

I now intend selling her and want to commission the building of a larger cat with all the trimmings but as importantly want a much faster boat and will use either two wings or two contoured foils.

The mechanics and operation of fixed folis or wings is literally childs play and want to further demonstate on a larger boat how effective this form of sailing can be.

To view my current yacht enter LARINKA into Google and up she comes or
visit www.planesail.com

I have business interests in the Philippines and India and know boatbuilders there who could build a craft for me. The main saving is the labour cost which here in the UK is circa 55% of the overall cost so makes it literally uneconomic to build here. Larinka was built in our naval dockyard in Plymouth and John Walker the designer went into Chapter 11 having spent £15m and only ever built four of these boats !!!

I am going to Manila in three weeks so would love a design to show to the boatyard there who already produce multihulls.

So I am game to get one costed up out there if you want to see something like this put into reality.? Kind regards James Wright

Spiv

09-07-2009, 01:19 AM

Hi James,

I am about to build a 17 x 8.3m composite cat.
I had the hull designed by Richard Woods and I designed the superstructure and whisbine style CF mast with 3 furling sails.

The hulls are very slender, but there is a lot of space above WL in the hulls.
Dry boat weight should be 7.5 ton, cruising design displacement 13 ton.
Bridgedeck clearance 1.1m.

Please send me an email if you want to discuss more as I do not want to hijack this thread.

brian eiland

09-07-2009, 10:34 AM

Well shall we try and make this a reality ?

I am the owner of the last Walker Wingsail built and in the nine years of ownership have rebuilt Larinka and can safely say the Wingsail works perfectly .

I now intend selling her and want to commission the building of a larger cat with all the trimmings but as importantly want a much faster boat and will use either two wings or two contoured foils.

I have business interests in the Philippines and India and know boatbuilders there who could build a craft for me. The main saving is the labour cost which here in the UK is circa 55% of the overall cost so makes it literally uneconomic to build here.

I am going to Manila in three weeks so would love a design to show to the boatyard there who already produce multihulls.
Interesting. I posted some of this WingSail info over on another forum as well:
http://www.yachtforums.com/forums/general-sailing-discussion/12037-wingsail-video.html?posted=1#post84426

]So I am game to get one costed up out there if you want to see something like this put into reality.? ....."will use either two wings or two contoured foils"
Do you have any sketches (even rough ones) done up of what you have in mind? Difficult to even talk any figures without some basics.
...and what do you mean by two contoured foils?