Alternative to marvelous Buccaneer 24

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Yeah, whose counting. But now that you mention it I forgot one -just for Gary:

 

Yes and YOU keep your cool Chris.
Theres no need to flame another member on the thresd---regardless of your personal opinion of them.

 

Gary, how do your foils work? I'm familiar with fully submerged and surface piercing foils(like Hydroptere and Doug Halsey's 18, and others). The fully submerged foils seem to have to have some sort of altitude control system(Rave, Moth, Mirabaud). Your "J" foils are similar in appearance to the "J" foils on the Hobie trifoiler-which uses an altitude control system, so I'm curious:
--How do you control them so that they don't lift too much or too little?
--Does the crew have to manually adjust angle of incidence?
--Do you sail with both forward foils down or is the windward one raised ?
--Do you have a designed maximum lift for each or both foils?

 

Doug, you're getting too far ahead, I'm just in the early stages of shaping them at the moment. The way I see it you design the foils so they JUST do the job (this is suck and see stuff), not too much lift, and not too little - although the latter is more preferable because too much leads to crashes because of ventilation from climbing too high... and too little, well, ease the main ... and later, increase the foil area, not so difficult. Also with fixed foils (I like 3 degrees angle of incidence) and sitting on a light boat platform .... you can shift your intelligent ballast to trim the boat. This is obvious stuff like hosing downwind in waves, you get your weight aft and out to windward, like on any yacht type. Actually my J's will have the upper dagger area set at a 15 degree angle so they will be somewhat like Hydroptere's and will self control the attitude plus the lower curved sections will produce generally upward lift - a combination of both schools. Everything is a compromise.
On Sid, the windward foil could be lifted BUT I like main beam dihedral (so the platform leans to leeward) and therefore the windward foil will be free of the water surface anyway. This is how Harry and Groucho sail, only leeward foil and IT rudder in the water. I look at Hydroptere dragging her large windward foil in a great plume of smoke and fine spray and think there is a lot of drag there. But it stops the boat from rocking too much from overpowering lift on the leeward foil. Again, for me, it will be a suck and see situation. In a perfect world you want just enough lift to do the job, a stable platform and drag kept at a minimum - and Hydroptere has plenty of drag in light conditions - see jpeg of Groucho Marx's windward foil and float in ultra light.
Since Sid is going to end up a very light platform with an overpowering wing mast/soft sail rig, the boat will have to be handled with some care ... that means a sensitive *** and uncleated main sheet or traveller - and the main will have to be played in stronger winds - just like any other lightweight yacht.

 

So,basically, these foils allow you to use a smaller ama than you would otherise,right? But you can't really fly the main hull-is that correct?

 

There is an inverted T rudder too. When I look astern at speed on Groucho the only sign of wake is where the rudder is cutting through the water .... sooo, guess I must be flying. Harry, with the shallow inverted V float foils, is now more a foil stabilized boat ... but in heavy gusts, the bow comes out and only the tip of the transom touches water ... so close to flying then too. But yes, in Harry's case, mostly the main hull stays attached.

 

Design Ratios, ect?

Gary, just curious: why in 7 pages on this design have you not posted any technical design stuff-like SA/ws ,foil areas, foil loading, RM, a direct comparison with the technical characteristics of the 24? No technical detail at all?

 

You know me Doug, I'm one of those intuitive, arty farty types who design as they build and make changes hourly, work by "feel" and "empirical" knowledge - dangerous ******** who are not to be trusted. That is why I never have fantasies of going into production boat building.
How about this: righting moment will be "very high" because of the overall beam, foil area will as "low as I can reduce them too" and yet still work, sail area will be C Class but with reaching sail additions, boat weight will be "as light as I can build it" and still stay together. If you're wanting a string of orgasmic numbers ... sorry mate ... but be patient, when Sid is finished, you'll get the lot. I'd rather do it that way, based, measured figures on reality, rather than to fantasize with a foot long model and some wild dreams.

 

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Hmmm-a Roto Tri and no wild dreams? Who are you kidding?

 

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Sure, Gary. But then you might consider that most designers use these and other details developed in the design stage to help them set realistic targets and understand where things could be improved before they need a chainsaw to do it.
But that's them and this is you, huh?

Eric makes it easy for you:

 

Most designers these days also know how to work a computer CAD program and run hydrostatics, but hey, we all know that you got a written exemption from SNAME and that crudely fashioned balsa chunks are now OK as professional design particulars.. and hey, they don't have to make sense. They are real simply because they sit there.

When you get yourself up to speed on what professionals are doing to design boats, Doug and you can actually do those tasks yourself, you can call-out others who are building boats that carry humans and work as planned.

 

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What an absurd comment! Whether you use cad or hand design has ABSOLUTELY NO BEARING on the use of Design Ratios-particularly in the comparison of one boat with another. Design Ratio's have been important as long as people have been using science to design boats. Of course, some people reject science even while they use cad.....

 

So, it's easy then, isn't it? How about you show us some of your scaled, dimensioned drawings from which any professional boat builder could fashion a proper boat of your design?

Follow that up with the build photos of your loudly proclaimed Trapwing so that we can see your mastery at work. A mastery that far exceeds the boats done by Gary... you know, boats that actually work and you can prove it.

Failing those tasks, Doug, I don't see how you have any meaningful contribution to make to this discussion. You can't draw and you can't build.

We'll let you know when we need that hot air bag for the party we throw at the next launching.

 

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You really don't know what you're talking about.
Guess that explains why in any thread where you post a rendering on this DESIGN FORUM you NEVER post technical details-not once....
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Speaking of the very bizarre, very weird and very disturbed: What do these names have in common: "Crabalocker", "Big Oz", "Vince"? You simply wouldn't believe the answer-pm me if interested......

 

Here, smart boy, is a link to a design of a 33' trimaran by Jim Antrim from his web page: http://www.antrimdesign.com/trimarans/85-PR.pdf

As you can see, Jim does not list any of the precious technical details, which you find so important. Now, if you want to question Antrim about his lack of professionalism on the subject, please feel free to pick up the phone and call him. Remember to scold him for being so out of touch with the marine industry... as you see it. I'm sure he'll get a kick out of hearing from you and your superior take on how he should do his work.

Please stop making a fool of yourself, Doug.