Cattrawler designs

Discussion in 'Boat Design' started by Greenseas2, Aug 2, 2009.

  1. Greenseas2
    Joined: Mar 2006
    Posts: 367
    Likes: 10, Points: 0, Legacy Rep: 49
    Location: USA

    Greenseas2 Senior Member

    I just returned from paying the dock fee for our 30 foot S2 center cockpit boat at the marina. $10 a foot for dockage, $50 for 30 amp electricity just to keep the batteries up and $30 for water that is used for a half hour once a month to wash the boat down....plus tax. In that boat dockage charges are by the linear foot, the thought here is to design a trawler with cat boat dimensions with beam being 49% of the length. A 24 foot cat boat hull would have an approximate beam of almost 12 feet and, if carefully designed, have more usable space above and below decks than the Grand Banks 32 or the Marine Trader 34. Additionally, a cat trawler would draw less than either of the other trawlers and require less power for the same speeds with lower fuel consumption for longer range on equivalent tankage (300 US gallons). For sure, dockage would be significantly less and properly equipped, mooring out is even less expensive if you have a wind charger or solar panels to keep the batteries charged. I would deviate from the usual chunky trawler superstructure design in favor of something more modern and futuristic that works with the plumb bow of a cat boat. The plumb bow is one feature that provides a lot more space forward than tapered bows as well as a lot more lift in choppy seas. To dampen roll with round chines, lengthwise skegs that are cupped to the inside would be effective, (concave) and have little drag effect. Thoughts?
     
  2. marshmat
    Joined: Apr 2005
    Posts: 4,127
    Likes: 149, Points: 63, Legacy Rep: 2043
    Location: Ontario

    marshmat Senior Member

    I take it you're thinking catamaran, not catboat?
    Well, there's the Aspen power proa ( http://www.aspenpowercatamarans.com/pages/28AspenC-90.html ) although they start at about four feet longer than you're thinking of, and aren't in production yet.
    You could slap a full cabin on a Glen-L Wildcat 24 ( http://www.boatdesigns.com/products.asp?dept=900 ).
    There's also the C-Dory Tomcat 255 ( http://www.c-dory.com/boats/tomcat/catamaran-255/ )
    The list goes on.... it's definitely an avenue worth exploring. Cheap dock fees, though, mean small LOA, which negates one of the catamaran's main benefits- its ability to have very long, slim hulls for a given displacement.
     
  3. apex1

    apex1 Guest

    Careful Matt, some of the "experienced" will shoot at you for that statement! :D
    Although it´s the plain truth.
     
  4. Greenseas2
    Joined: Mar 2006
    Posts: 367
    Likes: 10, Points: 0, Legacy Rep: 49
    Location: USA

    Greenseas2 Senior Member

    Cat boat trawler

    Hi Matt,
    Nope, I'm talking about the old and proven single hull cat boat that is beamy and seawothy in design. Let's work with that concept for a while. Dock fees calculated by LOA are large, when they start charging by beam width, we start thinking about building upward. Got the picture? LOL
     
  5. messabout
    Joined: Jan 2006
    Posts: 3,367
    Likes: 510, Points: 113, Legacy Rep: 1279
    Location: Lakeland Fl USA

    messabout Senior Member

    This a dilemma that has been kicked around for a while. Bolger, before his demise, was rather outspoken about the subject. I read somewhere that the ground rules in Alaskan fisheries tend to force boats to become very wide, perhaps foolishly so. Dockage is certainly a factor but taxes are also asessed on the basis of LOA in many locations.

    The whole idea of short fat boats is counterproductive if the boat is to be used often. A long skinny boat is much more economical to operate. More comfortable in a seaway too. So we are obliged to weigh one set of cost factors against the others. If your boat is a marina queen who never slips her moorings then build the boat nearly square. If you use it every day then that is a different deal altogether.
     
  6. marshmat
    Joined: Apr 2005
    Posts: 4,127
    Likes: 149, Points: 63, Legacy Rep: 2043
    Location: Ontario

    marshmat Senior Member

    OK. So you're thinking of a Nonsuch ( http://en.wikipedia.org/wiki/Nonsuch_(sailboat) ) minus the mast and keel.

    As any Nonsuch owner will testify, these relatively heavy, relatively beamy boats pack quite a lot of room into their relatively modest length.... couples routinely spend months at a time living aboard the 26- and 30-foot versions.

    A power trawler based around a similar concept could definitely be appealing to some folks.

    messabout, you see the same sort of thing in the Maritime provinces.... fishing regulations have had LOA-related provisions in them for long enough that the commercial fishing fleet has grown wide and tall. The fuel bills, needless to say, are hurting many fishermen pretty hard.
     
  7. Greenseas2
    Joined: Mar 2006
    Posts: 367
    Likes: 10, Points: 0, Legacy Rep: 49
    Location: USA

    Greenseas2 Senior Member

    New England Catboats

    Catboats were first used in te New England fisheries and had a small cabin forward. Later, the cabins were lengthened for private cruising use. There is still one or two working cat boats Down East one in the lobster fishery and one in the clam industry that I'm aware of. Marshall, Crosby and Menger catboats are well known and are frequently used as long distance cruisers. Also the 24 foot Atlantic City catboat has a huge amount of space and an impressively spacious cockpit. I've personally sailed one for a two week period far off shore in some not-so-nice weather. Cat boats do have volumes of space and could make ideal trawler type vessels. As you mentioned, beating the tax and dockage costs should pay for the boat over time. Only minimal power from a small diesel will furnish a nice 6-7 knot cruise speed at economical cost. Aside from weekend sailers, I don't believe anyone wants a big fuel burner these days. Just a note,we've used pure, locally produced biofuel in our diesel engine with no adverse results.
     

  8. narwhal
    Joined: Aug 2009
    Posts: 68
    Likes: 1, Points: 0, Legacy Rep: 45
    Location: Nashville, TN

    narwhal Junior Member

    These are all traditional round bilge hulls, not that that's detrimental to your idea. You may also want to check out the hard-chine catboat designs of Wittholz, which may be easier for one-off construction.
     
Loading...
Forum posts represent the experience, opinion, and view of individual users. Boat Design Net does not necessarily endorse nor share the view of each individual post.
When making potentially dangerous or financial decisions, always employ and consult appropriate professionals. Your circumstances or experience may be different.