Click for Cross Click for Lurssen Click for Westport Click for Nordhavn Click for JetForums

55´Power Catamaran?

Discussion in 'Yacht Renderings & Plans' started by AMG, Feb 12, 2005.

You need to be registered and signed in to view this content.
  1. AMG

    AMG YF Moderator

    Joined:
    Jul 26, 2004
    Messages:
    5,243
    Location:
    Sweden
    Together with a fellow-member at the Forums, I have made some proposals for a GRP powercat in a size where we think a catamaran is big enough to make use of the internal hull space, still small enough to fit into the marinas.

    The first idea was to use the current trend among sail-cats, with straight bows and avantgarde superstructure. Second thought gave that it might be too much new ground to break, so today the concept is more like a cabin-cruiser people can relate to.

    At 55 feet the beam will be about 22 feet and powered with the new Volvo-Penta IPS/500:s she will have a sweet cruising speed of 25 knots and up to at least 35 knots top speed. The IPS drives will also reduce the draft.

    Before we go any further, it would be nice to hear from the YachtForums members if you think this is an attractive concept and if the styling is what you would like to see on such a boat? Any and all comments are welcome! :)

    /Lars

    Attached Files:

  2. D'ARTOIS

    D'ARTOIS New Member

    Joined:
    Jan 21, 2005
    Messages:
    45
    Location:
    Holland/France
    55' design Cat

    She certainly looks nice, the newly designed Volvo engine is placed midship, so that saves a 2nd engine and gives a more efficient engine configuration. I wonder if you can get the prop deep enough to avoid dry running in following seas.
    Most probably she will sink in a bit more when she is loaded.
    Have you already made your weight calculations? About 10/12 tons displacement unloaded?
    Looks good,
    Brien
    Last edited: Feb 12, 2005
  3. AMG

    AMG YF Moderator

    Joined:
    Jul 26, 2004
    Messages:
    5,243
    Location:
    Sweden
    Hi Brien, yes she is a Cat I would like to have myself.:)

    But she actually should have twin engines, which btw is the only option to buy them today. But the nice thing as compared to any other engine, you will have the engines mounted horisontal while the drive is leaning to the center of the boat to operate in pretty undisturbed water. The hulls are symmetrical and with progressive V-shape. The draft on cats I am not used to calculate so she might sit a little deeper with these engines. Total weight is too early to estimate, but she will be built with PVC-foam cored vinylester and lightweight interior to achieve the desired speed and fuel economy.
    I think the forward mounted props at cruising speed will not cavitate from following seas, but I am glad you are pointing at such things.
  4. BarryClay

    BarryClay New Member

    Joined:
    Dec 23, 2004
    Messages:
    25
    Location:
    Chesapeake
    Didn't we see this style in 1950? How about something more dramatic, I mean if we are going to start turning the engines around how about the whole superstructure..then we could drive from the bow! That would be really entertaining, at least for the one not holding the drink! :)
  5. AMG

    AMG YF Moderator

    Joined:
    Jul 26, 2004
    Messages:
    5,243
    Location:
    Sweden
    Not exactly going backwards, but this early drawing might be what you are asking for? This is one of the most interesting issues with powercats, will people buy more extreme designs or do they want them to look as traditional boats, except for the twin hulls?

    (PS, you dont have to quote the entire post to reply, there is another button or you erase the parts of the quote not belonging to your reply. Makes the threads shorter... :))

    Attached Files:

  6. D'ARTOIS

    D'ARTOIS New Member

    Joined:
    Jan 21, 2005
    Messages:
    45
    Location:
    Holland/France
    Hi Lars,

    No, the last design is no improvement. Clients looking for a powercat are looking for comfort, a fast and economic ride but no extreme designs. At least, in my opinion.

    Do you have more than this profile? I am curious how you placed the engines, I thought to see only one pod instead of two. Do you have interiors as well?

    Presently I am playing around with a 46' tri design in the style of Gilles Vaton, powered by a 1000 hp gasturbine. Can do maybe a little over 100 mph, not so fast as the boats from the Turbine people elsewhere in this forum.

    Those engines can be procured for little, although the marinisation might cost something; as soon as the design comes our satisfactory I'll load a few thumbnails up.

    Regards,
    Brien
  7. AMG

    AMG YF Moderator

    Joined:
    Jul 26, 2004
    Messages:
    5,243
    Location:
    Sweden
    My impression is like yours, people want the cats to look like boats and this might be the reason why the boxy cats we see are not selling so well, at least not in our waters where they otherwise would be ideal?

    I have no interior made yet, waiting to settle on the exterior first. The hulls will be around 2 meters wide inside which allows for pretty nice cabins below.

    The engines should be mounted as they are intended (see picture) on a V-bottom hull, but facing each other instead of pointing outwards. Must be even better!

    On gas turbines, I love the sound! We had one of those skiboats running here last year and I was looking up for a helicopter...! Biggest obstacle on yachts is the cooling, which is often making the installation as big as a diesel with all the covers. Another is that they should not be sitting for months like yachts often do, turbines are better off where they are frequently used.

    Looking forward to see your design in due time! :)
    /Lars

    Attached Files:

  8. YachtForums

    YachtForums Publisher/Admin

    Joined:
    Dec 22, 2002
    Messages:
    19,634
    Location:
    South Florida
    Lars,

    My brother just bought this Cat with a pair of diesels. (the only one ProKat has produced so far). This boat has become fairly popular along the intracoastal in South Florida, as I'm beginning to see more of them on a regular basis. I really think they are onto something by connecting the sponsons with a V-shaped, mono-hull like deck. This not only offers increased deck space and provides a good bow-pulpit for anchors, but they are aesthetically more attractive and it appears more buyers can "relate" to them.

    The pictures below are for reference purposes from ProKat's website. The overhead view shows the increase in forward deck space, while the side view shows the anchor pulpit.

    This is a design that another manufacturer has adapted too. I'm certain that others will follow. Personally, I think this feature should be given strong consideration on your 55' PowerCat.

    Attached Files:

  9. AMG

    AMG YF Moderator

    Joined:
    Jul 26, 2004
    Messages:
    5,243
    Location:
    Sweden
    The January issue of the French magazine Neptune is focused on powercats and most of them are without this fore deck. Only the Catana Legend, a 45-footer has it, but not going so far forward as on your pictures. There is also an interesting Vaton designed 80-footer to be launched any day, sporting some "Wally-lines" with a large seating area on the fore deck. I´ll see if I can find a picture somewhere...

    Attached Files:

    Last edited: Feb 16, 2005
  10. Ben

    Ben Senior Member

    Joined:
    Feb 9, 2005
    Messages:
    176
    Location:
    Melbourne Australia
    Have any of you gents checked out the New Zealand Yachts web site?

    They've got a few good ideas. ;)
  11. AMG

    AMG YF Moderator

    Joined:
    Jul 26, 2004
    Messages:
    5,243
    Location:
    Sweden
    Yes, they are building some nice yachts. They are however much bigger and the downside of wavepiercers is that the hulls will be too narrow to live in, if you plan to make yachts half the size of theirs.

    I also think they will be very wet do drive in smaller sizes, why a more traditional catamaran hull is a better option on a 50-footer.
  12. D'ARTOIS

    D'ARTOIS New Member

    Joined:
    Jan 21, 2005
    Messages:
    45
    Location:
    Holland/France
    The Cat Design...

    Lars, you see for yourself, you are definately on the right track. Like I said the other day, I just play around with the Tri idea à la Gilles Vaton, also inspired by the gasturbine-desings yhat are popping up.

    So little by little "Amster****ed" came up and keep in mind that this is just a "plaything" that could be build but due to its narrow hull of 3,50 meters, the 49'
    has only little interior comfort. Powered by a 1000 hp + gasturbine and her very light hull weight - 4 tons only - she can real push forward.

    Later on, I show the interior space, not much - just enough for 2 cabins, kitchenette
    and shower/toilet.
    Due to her high speed hull, deckfittings are flush mounted and wingdoors in the cabintop give access. Draft is about 1' - Loa 14.70 x 3.50 (wo amas).

    Attached Files:

  13. BarryClay

    BarryClay New Member

    Joined:
    Dec 23, 2004
    Messages:
    25
    Location:
    Chesapeake
    Now were talking...this is very interesting in that it retains the original 30's classic feel for a bit of tradition and adds the technology of today.. Has anyone considered moving the new volvo penta engines to the front in a tractor position via a pusher position? Also, on the previous cats they are a bit too boxy for me, I still think a tri hull might be the best of both worlds..:confused:
  14. YachtForums

    YachtForums Publisher/Admin

    Joined:
    Dec 22, 2002
    Messages:
    19,634
    Location:
    South Florida
    At the Miami Show, there were a number of new cats in the 40-60 foot range, by some new manufacturers. It appears this is a sector that's growing. More details later. Off to the show now... :)
  15. sangria1

    sangria1 New Member

    Joined:
    Aug 1, 2006
    Messages:
    1
    Location:
    La Guaira venezuela
    Yacht Fisherman power cat

    I am looking for a yacht fisherman power catamaran, thomething that could resemble an Hatteras 58 YF but with twin hulls and a real copkit, no two protuding pontoons and funny tear shaped windows, It could be in the 58 to 65 feet range. Has anyone run into any design that could meet this criteria?
    Thanks in davance.
  16. 84far

    84far Senior Member

    Joined:
    Dec 15, 2008
    Messages:
    833
    Location:
    Brisbane, AUS
    hi Lars

    IMO, i would have to say stick with the first design. i think that the majority of people still want the normal mainstream design when refering to this size of boat. i guess the only thing u can do to make it stick out from the rest is play around with window design, engine in/out lets, chines etc, i think u get the idea.

    far
  17. 84far

    84far Senior Member

    Joined:
    Dec 15, 2008
    Messages:
    833
    Location:
    Brisbane, AUS
    hi Sangria1

    theres not much out there that i would consider a SF powercat, but i did come across this one in my travels.

    http://www.powercat.com.au/innovation60.htm

    she is 60', has a nice cabin, nice cockpit space, nice floor plan, and buy the pictures she can get up and rumble aswell (35kts). i would say u would have to kit the boat out yourself in regards to towers/out riggers/chair etc. i think this company are a bit new on the market, so not to sure what problems they have had.

    far
  18. Kafue

    Kafue Senior Member

    Joined:
    Nov 29, 2006
    Messages:
    1,151
    Location:
    Gold Coast Australia
    Hi,
    Interesting to read this thread after all this time has passed and yet not much has happened in the "style" side of cat design. Probably a lot more in technology given the move toward "greener" boating, especially in Europe.
    From a users point of view (rather than a designer/builder etc) my priorities in a 55 ft boat would be:
    good usable cockpit. Now this becomes a bit of a problem in a cat due to the clearance needed between the hulls. Esp in a sportfish model. Also, too many builders IMO put too much fixed seating in the ckpit.
    If there is a lower station & the vessel is over 50 ft, then access from the lwr station to the sides/bow as in a pilothouse. This in turn forces the design to enable wider access on the side decks, a great feature. OK you sacrifice saloon area etc, but it is a good trade off.
    Too many cats have that "caravan" look/feel internally.
    Cabins, especially master need an island bed, another issue with the usual narrow hulls.
    Styling IMO, NO MORE teardrop windows!!! If the style is different from the "norm" it will not matter if it follows function.
    Like this boat: 53’ Cat Cay ~ 2004
    Like the style of your design.
  19. brian eiland

    brian eiland Senior Member

    Joined:
    Jul 28, 2004
    Messages:
    2,853
    Location:
    St Augustine, Fl and Thailand

    Attached Files:

  20. brian eiland

    brian eiland Senior Member

    Joined:
    Jul 28, 2004
    Messages:
    2,853
    Location:
    St Augustine, Fl and Thailand