Location: San Francisco It looks like a piece of crap with negative value, to me. The keel is weirdly tiny, and it looks suspiciously like someone has hacked out part of whatever it was made of first and replaced it with a hunk of lead(?) in a (probably hopeless) effort to make the thing stay upright. If it had actually sailed at one point in its life, it might be a fun project to bring back to life -- still a big financial loss, but educational and fun if you're in to that kind of thing.
Location: Cathlamet, WA It looks like it could be a John Brandylmeir (sp?) design.
Location: San Francisco Out of curiousity, what makes you think it's a Brandlmayr design? I poked around, and all the designs I found seemed to favor a more traditional sheerline and rather more rake to the stem.
Location: Cathlamet, WA While sailing near Campbell River about 35 years ago a 24 foot sailboat designed by Brandlmayr sailed by us quite handily on a similar sized boat. ISO and GL » Thread Tools Show Printable Version Email this Page Display Modes Linear Mode Switch to Hybrid Mode Switch to Threaded Mode Search this Thread Advanced Search Similar Threads Thread Thread Starter Forum Replies Last Post Through-hull for steel sailboat - how to do it ? When making potentially dangerous or financial decisions, always employ and consult appropriate professionals. Would this vessel have to be a hydrofoil or multihull, or could a monohull with a hinged transom of sorts convert a double ended full displacement hull to a squared off planing hull?
Location: Australia Displacement-type cats probably the most likely candidate for a boat that can operate efficiently over a wide speed range. Location: Australia If such things were easy, or practicable, or affordable, they would have arrived on the scene by now. Location: NW Washington State USA One way to do it would be to hull a bit like a Handy Billy that at a bit less than hull speed would have her transom out of the water and present an excellent full disp hull form to the water. Location: Sweden As far as I've understood there isn't really a maximum (displacement) speed for long and narrow hulls.
The performance of any boat, and especially a multihull, goes out the window if you overload it. Location: Everson, WA From the thread, I am leaning t'ward a catamaran with hyper narrow, deep hulls. Location: Australia There is no miracle design that will do everything better than all others. The subject of efficient power boats interests me, especially in the 10 ? 20 knots speed range.
If fuel efficiency is the only criteria and length is not a restriction, a long and narrow monohull is the answer. A conventional trimaran has stabilizing amas that extend outside the sides of the hull proper. Another variant on the stabilised monohull theme is the displacement glider, also called box keel boat. Seahorse Plastics has a long history of fiberglass fabrication for sailboats and other marine applications since the company's inception in 1960. Our company possesses the experience to design and build your next fiberglass marine idea, sailboat and other fiberglass marine vessel design, or repair of damage to your fiberglass sailboat hull here in the general Hampton Roads Virginia region. Rudolph Lotz had a love affair with designing and building boats that dates back to his early manhood, when he built six small wooden boats in the 1930s.
The work was displayed in a July 1985 National Geographics review about Hampton Roads, Virginia with a photo of their fiberglass naval training ships featured in the article.

High performance underbody creates speed but also lack of directional stability and quick, uncomfortable motions offshore.
Full Keel means control but at the sacrifice of performance, windward pointing ability, and maneuverability. Proven combination of the two extreme types creates a hull that have these characteristics: high pointing ability, excellent directional stability, easy tacking (light wind), and high mobility during docking situations.
The Contessa 32 has a reputation as being one of the better 32 footers for weathering a serious gale, and rates right up there as one of the more seaworthy boats for bluewater cruising.
By this racing boat example, we can see that are better served if we strike for the middle ground.
In terms of maintenance, the proper care of any vessel involves keeping up its paint system.
All Web Site Graphics, Layout, and Written Content at this Domain Created by Michael Kasten. The underbody just looks wrong, and in the absence of evidence to the contrary, I think it IS just wrong.
I've seen the HYSUCATs, and would like to get feedback on a trimaran (HYSUTRI?), or another hull design. Transom extensions might make some theoretical sense, but in practical usage, transitioning from one mode to the other, on water, would likely be problematical.
But because of her rockered bottom w more power she'd pitch up, squat a bit and have a submerged shape much more like a planing hull and go gracefully at speeds much higher than disp. I guess that this is because it is easier to make a practical boat with a catamaran hull than with a trimaran hull. Ultra narrow catamaran hulls might be attractive for their minimal wave-making resistance, but cause hobby-horsing running into a sea, as well as being very sensitive to fore-and-aft weight distribution. I estimate that the boat that fits my requirements has a displacement around 4 tons, so I?m looking at long and narrow hulls used in displacement mode. The platform connecting the two hulls needs a clearance of half a meter or more to the water, to avoid waves slapping into the platform. This arrangement complicates handling in harbours so I?ve ruled out a conventional trimaran for myself.
The box keel provide maybe 80% of the buoyancy, provide standing height in the forward cabin and can accommodate engine, fuel, water and technical installations. My hope is that such a boat can be made in the spirit of the beautiful power boats designed by CG Pettersson during the first half of the 20th century. The Lotz family has built several sailboat racing hulls through the years, as well as performing sailboat hull repair and remodifications.
He chased this passion well into his 80's after retiring as Vice President of Virginia Chemicals, Inc. It is a blending of two types of extreme hull designs to create a proven design that is safe, strong, and seaworthy. In fact, it was the smallest boat to finish the infamous 1979 Fastnet Race (known as the deadliest race in history of modern yachting).
I'm a cabinet maker by trade and not a boat builder but this looks like a well built hull and deck that I am considering picking up and working on but no plans are available and the original builder has passed away so there is no information available to me as to the design.
A tri could cruise on a small diesel in the center hull and have big block chevrolets with jet drives in the outer hulls. Hydrofoils sound great, until one hits anything more solid than a duck and somersaults into oblivion.

Gracefully that is excluding the fact that her bow would be ungracefully high in the air, subject to winds that could make a mess of directional stability.
From boat data I've seen, and my own calculations using Michlet, long and narrow hulls are used at speeds up to around 20 knots for a 12 m long boat. I wouldn't count out a mono-hull Tlinget or Otter types either (people in the Northwest will know what I'm talking about). If you also want a useful boat, a monohull has to be considerably longer than 12 m to provide an acceptable beam. Anything you build on the platform will have quite a high CoG so you will need a minimum total beam for the catamaran of 3 m - 4 m for stability and to avoid excessive wave interference between the hulls.
The clearance to the water for the hull spanning the distance between the main hull and amas still needs to be around half a meter with resulting high CoG. The Contessa 32 is a no non-sense design that does not attempt to trade seaworthiness for a larger interior or to mimic apartment-like accommodations below decks. Its a little hard to start talking to people about rigging without knowing what to call her. The idea would be to waddle along at single digit speeds for maximum range, then roar over the horizon when the Somali pirates show up. First hand experience with a planing hull at displacement speeds proved to me that just pulling back the throttles does not save much, if any, fuel.
Michlet is based on theories for wavemaking that is applicable for long and thin displacement hulls and consequently is most relevant when wavemaking is the major resistance component. My search is for the hull(s) design that goes the fastest with the least power, then I can work on a compromise of accommodations, tankage, complexity, initial cost vs long term cost, etc. For adequate initial stability, the total beam needs to be more than 3.5 m for a 12 m long boat. Both built several custom fiberglass hulled sailboats together for racing on the Chesapeake Bay.
As a result, it is a little less beamy and roomy that may other 32 footers on the used market.
If you go for planing multihulls you will sacrifice efficiency at low speed for a higher top speed, but the low speed efficiency might be adequate for your needs anyway. The data LWL = 20 m, BWL = 2 m, draft = 0.5 m, displacement 12 tons approximately describes the minimum useful displacement for a monohull (for speeds around 15 knots). A trimaran would have room for an engine in each hull, max range in the center engine, max speed with all 3 engines, and something in between on 2.
It sounds good until factoring prismatic coefficients (and other formulas naval engineers have a total grasp on) for different speeds. A wise man once said the most efficient way to go through the water is not to go through the water, but the air instead, with as little of the boat in the water as possible. I have had a bit of change of thinking about this recently, and will shortly be testing a new idea via some scale models, if it's got legs I'll post some news.
The boat I have experimented with is unfortunately a bit too heavy to get a good response from, with the air cavity size it has.

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