~ Wadda ya think ??
http://youtu.be/0FQPgC8jgBY

Looks neet. Pete Goss did it with his Team Philips back in year 2000, but the bows kept breaking off!

Here's another twin masted cat;

http://www.youtube.com/watch?v=AY0ssDA70gY&feature=related

Less wind aloft, sailing really flat and stable. Cool!

Yeah, if you look closely at the bows of the cat vid. I posted above, you'll see they are shaped like the hulls on a float plane, fat and flat forward, with a step half way back. They are designed to be sailed flat, on two hulls, and get up on the 'step' to plane as soon as possible, and reduce drag that way, rather than by flying one hull. BUT...in light air, I think those hulls would be very slow.

wonder if the leeward sails get any spoil from the windward set, or if they're creating some sort of slot between the two?

Who was that team in the Volvo race with the fully rotating wing sails on their multihull? Broke apart before the race in a gale if memory serves?

you are thinking of Team Philips that Pete Goss put together for "The Race". That boat broke up in a storm mid-Atlantic in 2000.

yes. that's the one. It looked like it had a lot of potential (unstayed mast allowed for feathering at any angle)

I wonder if that design will ever get resurrected with newer engineering design and construction...

Here she is at rest: http://www.youtube.com/watch?v=C6nD...5D1C4803929D8F2&feature=results_main

And here she is underway, on her 'last ride': http://www.youtube.com/watch?v=tPHYDcB1p4M

This might be a better way to do things. I'm thinking the two masts might be better than one big one. You can get twice the sail area with less heeling force. The center of effort from the sailplan is kept lower. The two masts were used on the Hobie Trifoiler and the proa Crossbow.

Personally I think it looks more like the old Hydraplaneur than Team Philips.
It once set a 24hr speed record for boats under 60ft with an average of nearly 25kts over 24h!
Not sure what happened to her, I remember something about a capsize somewhere mid-atlantic.

Hydraplanuer also had the single handed speed record for a short time as well (that might be the record you are talking about though). It was a cool boat. I think Eeves gave up on it after that capsize.

If you just want straight up speed, in big air, yes. I don't think a similar scaled down design would work for what we do, ie. buoy racing over many different wind ranges. The tall rigs (think A cat) help get one hull out of the water in lighter air to reduce drag.

If you are going to design to keep both hulls in the water and use two shorter rigs, it will be a pig in light to medium wind.

I once witnessed a Hobie Tri Foiler regatta in light air (at Wildcat, many years ago) it was not pretty!

The A cats and all the other cats were going by them, they were nearly stopped. Never did see one up on the foils.

Maybe there is someone here who owned one and can tell us how much wind it took to get it up on the foils and go fast?

Timbo,
I sail a trifoiler a good bit and can tell you it is a pig in light air and doesn't go up wind worth a sheet, but it ain't no catamaran, so not a fair comparison. Now, when it's blowin' the thing is a blast gybing downwind on foils. G-forces in the turn that will scare you. That's about the only time it is a fun ride.

Thanks for the input Philip. That's what I thought and I would love to have one for the few really windy days I see here on my little inland lake, it looks like it would be a hoot!

But I thought DHO was thinking it might be "...a better way to do things..."

I'm not sure if he meant going faster, easier, in the around the cans racing we do, or if he meant just going faster in any direction (downwind mostly, but it sucks getting home!)

DHO?

Jonathan has brought his Trifoiler down to Flathead Lake a number of times over the last few years. He says it needs 15 plus to get up on the foils and stay there. Not a lot of fun if not on the foils, big fun when it is. Really a reaching and downwind machine.

Dave

Interesting idea, though not new.

Here is another such design:

http://www.multihulldesigns.com/designs_other/cat2fold36.htm


http://www.multihull-maven.com/Boats/Cat2fold_36

http://www.youtube.com/watch?v=eQwoq5AlPcg

it seems to me that the windward sail would be grossly disturbing the air to lee mast/sail

Does anyone know of a trifoiler that is for sale? I solo-sail a 17 but the trifoiler looks really fun as a speed rush.

Flight Risk served a breif stint as a test platform for a biplane rig when the previous owner wanted to test the concept in advance of designing a 60' cruising cat. Upwind powered both sails well, broad reaching was fine, dead downwind allowed the sails to be deployed outboard on opposing sides of the boat, leaving the tramp area amazingly open. On a beam reach, and maybe 20 degrees above and below, the windward rig did indeed shadow the leeward sail, which just fell gently inboard and sat there quietly. As a beam reach is a fairly fast point of sail for a catamaran, losing the power of 1 rig was not real annoying, the boat maintained about the same speed as going upwind. The owners conclusion was that the biplane rig, with no headsails, was really a fine solution for shorthanded sail handling aboard a big cruiser. No headsails to mess with, quite easy to reef the leeward sail while on a beam reach. If each sail had 2 reef points there were 5 configurations of decreasing sail area. When I bought the boat I returned it to its original sloop rig, with assym spin and roller furling screacher, significantly more sail area, complexity, and the ability to fly a hull, which I love to do. I'm not sure if that particular rush could be produced with a biplane rig. But it could be fairly high performance if designed as such, with headsails and sufficient sail area overall.


Dave

great info, thanks Dave