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Old 05-07-2017, 06:20   #76
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Re: No love for trimarans - why?

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Originally Posted by svrodeorm View Post
I fully understand that the beam of a non - folding tri is a deterrent for anyone keeping the boat in a marina, the fees are astronomical for a slender mono

For me, that's a non issue since I have 2-3 nights in marina during the last five years, don't embrace the feeling of getting settled I what for me feels like an apartment building. Of course we live onboard full time, so a different story altogether. We like cruising in remote areas, and the ability of tri to dry out on a bean, and with the help of some tidal action careen and even do Antifouling is amphorae interesting feature. The light weight, making a OB propulsion feasible norther huge advantage. A totally acceptable trade off for some more sparse accommodation at least in warm climates.

The down side is purchase price,for the most part for me and the fct that windvane steering as Fraser I understand is not quite up to the quick changes I boat speed and apparent wind angle.

Ada what else? What are the weak points, structurally on a trimaran?

Beam attachment to either the a as or the vaka comes to mind....anything else?

Everybody talks of capsizes, though those shuldnt be too hard to avoid, with some prudence for a non racing user, what else is known regarding failure modes?
RE: OB. hanging off the transom, plan on having it steerable. With no prop wash over the rudder low speed steerage is damn near nonexistent.
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Old 05-07-2017, 07:57   #77
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Re: No love for trimarans - why?

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Originally Posted by ZULU40 View Post
'adequate' isnt really the same thing and definitely doesnt describe stability, just ask yourself this question:

'between a trimaran and a catamaran, which is likely to lift a hull first?
'

What does lifting a hull have to do with anything? Trimarans are designed to lift the windward hull as soon a step they start moving, it's called the dihedral angle and it I simply critical to getting the windward hull out of the water to reduce drag and INCREASE RM. So any well designed trimaran will fly an ama long before a Catamaran should be lifting its hull.

As for ama buoyancy, low performance trimarans typically are designed with a float volume that exceeds the designed displacement of the boat. And it isn't unusual to see float volumes in excess of 200% the vessels displacement. The exact number varied a bit by design, but the whole point is that as the vessel I see pressed the leeward ama sink and as it does so the volume generates additional RM. which is why trimarans generate the most RM right at the point where the leeward hull I should fully submerged. But almost no trimaran will ever be pushed this hard, in fact must simply can't, there isn't enough power in the sails to press the boat this hard.


grip: keels grip the water slowing sideways progression. There was a one time quite an argument running about Macalpine-Downie Iroquois Catamarans which had a few go over (if anyone feels they can supply some history), some discussion reigned that the keel deployment was critical on one hull or the other was critical.

Meh, all boats have some mechanism to prevent leeway, trimarans typically use a mix of daggerboard in the main hull and increasingly daggerboards in the amas. But leeway is generally not a major problem with trimarans, the amas provide some directional stability and the daggerboard generally does a pretty good job of adding the rest.



IROQUOIS 30 MKII sailboat specifications and details on sailboatdata.com


waves: have velocity, within a wave the forward force measured linearly isnt constant its simply not possible for it to be so. The ramp up a wave is a gentler slope than the crest falling off the top, so linearly its slower on the steeper falling backside.



unchallenged you say
ok since you probably wont be happy with my choices, choose 2 boats a tri and a cat of the same class of boat suitable for cruising for which you supply weights, lines plans and dimensions and lets figure it out

'Wharram's paper was published in 1991, and is available from him named 'the Stable Multihull', or unless someone has a copy of that or the papers original name 'Unsafe in Any Sea'

https://www.wharram.com/site/catalog...on-2-technical

now have at it, and call BS all you like
Whharram's opinion was wrong, is wrong, and is simply a bunch of nonsense. He was primarily arguing that multihulls in general have (as of 1990) become to powerful and people should go back to slower boats. In no small part this is because his designs use lashed beam fittings instead of solid ones (functionally the same as tying a keel on instead of bolting it down) and so couldn't handle the loads applied by larger rigs. But what this has to do with modern designs I have no idea.

Having sailed large cats, large trimarans, and large monohulls (all over 70') I would always choose a trimaran for sailing performance, a cat for anchoring comfort, and a monohull for carrying lots of stuff. Given the preference and someone else's money I would always choose a large trimaran over the other two.
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Old 05-07-2017, 08:43   #78
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Re: No love for trimarans - why?

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Originally Posted by Cadence View Post
RE: OB. hanging off the transom, plan on having it steerable. With no prop wash over the rudder low speed steerage is damn near nonexistent.
If you have enough rudder for low speed sailing you have enough for low speed powering Mine was designed this way and maneuvers fine with tiller alone. You can tighten the turn radius steering the outboard too but it isn't necessary.
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Old 05-07-2017, 08:54   #79
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Re: No love for trimarans - why?

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This is the trimaran I refer to, that I have personally seen sitting, deteriorating at anchor, in the La Paz Magote, every year since 2011 (and probably from before that...).

Shuttleworth Design - DAMIANA
That sure looks like the one I saw.
At that time, it didn't have a rig.
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Old 05-07-2017, 09:02   #80
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Re: No love for trimarans - why?

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If you have enough rudder for low speed sailing you have enough for low speed powering Mine was designed this way and maneuvers fine with tiller alone. You can tighten the turn radius steering the outboard too but it isn't necessary.
Maybe we have had two different experiences. With the light displacement of a SR31 and a breeze, I wouldn't want to be in a marina with me coming in. With prop wash you can walk a boat without it in tight quarters your SOL.
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Old 05-07-2017, 13:39   #81
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Re: No love for trimarans - why?

The Nicol is very stable and predictable, probably because the amas are a bit more immersed than a Searunner. If you don't have the stub keel on a Searunner I'd suggest lowering the centerboard part way to take out some of the excitement. These boats are also easy to warp around. If it is really tight I'll just bring the bows in, hop off with lines to the ends and pivot it around. That way I can also turn it so it is ready to leave.
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Old 12-07-2017, 01:08   #82
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Re: No love for trimarans - why?

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Originally Posted by captaingregger View Post
I own a large (well, large to me) cruising trimaran. I agree they are indeed hard to find... and nearly impossible to find in turn-key condition.

What I love most about my trimaran:

#1 SAFETY. Cruising tri's are, by design, more inherently stable than their cat counterparts. It would take nearly 30 degrees of heel to flip a tri. It's more like 12 degrees on most cruising cats. I've never seen more than 5 degrees of heel on my tri. 2 deg is more the norm I see. But then I never fly a hull and I'm fine with 8-9 kts cruising speeds.

#2 SPACE. Mine has massive amount of deck space. I can store 3 dinghies on the deck and not even notice it. They're stored way out of the normal pathways. Then I still have the massive nets, as well as 3 sets of davits on the stern if I need to add more space

#3 flat water sailing, virtually no rocking in any anchorage. The boat is like a rock even in 30 kts of wind when at anchor.

#4 livable ama's. My ama's have as much room as a small studio apartment, Each one has massive amounts of closet and storage space, it's own private entrance, it's own ensuite lav and shower and of course a massive queen size berth. This allows me to give me guests ultimate privacy while reserving the aka (main hull) for entertaining, cooking and of course the owner's v-berth forward. There is also a hugh aft cabin but I keep that as my office/ workshop. Which keeps clutter down to a minimum in the main cabin and pilot house.

#5 Enclosed pilot house. My tri has a pilot house that keeps me dry despite the roughest and wettest of passages as well we out of the sun when it's blazing hot outside. It has both hard windows that open as well as stratoglass windows that roll up for ventilation when it's not raining. Because the pilot house is set way aft by design, very few waves ever reach the pilot house even if beating to windward in a

#6 Storage. Perhaps an achilles heel for trimarans is the massive amount of storage, something that can cause an owner to weigh down the boat. But I am strategic about it's use and this allows me to move bulky items off the deck and into cavernous storage lockers of which there are 7.

To each his own with respect to boating. I don't think any one boat is better than any other all around. You give up something to get something in every design and ownership equation. But I have never been so pleasantly surprised at what I get with this boat, speed comfort, upwind tracking, peace at anchor, than I have with the many other boats I've owned over the years. And I say that coming from a pretty hardcore monohull background.

There's nothing really wrong with my boat, per se, I can leave on 60-day passage on her tomorrow if I wanted. So she doesn't really need refit in the traditional sense of the word. However, in November we're taking her to the Philippines for some upgrading to add some of the more modern accoutrements that new production cats have so that we can enjoy her a bit more on my 20 yr global cruising adventure. We'll be raising the mast 38", adding a huge fiberglass canopy that will extend from the mast base to the stern, thereby allowing us to improve the pilot house setup to a modern more open design style, as well as a few tweaks to the cabin to allow for easier ingress/ egress from amas to the main hull. We think the project will take 8 mos but I've put aside 1.5 yrs for it, due to possible overruns (we all know how that goes). When all is said and done I'll have a boat that is every bit as comfortable as a 2017 production cat in the same size class but at 1/8th the price.

We all know boating is an expensive hobby/ past time. So I think the challenge for most of us is how to accomplish all that desire we have to get on the water and explore, while balancing out the fiscal insanity of being a boat owner.
Look forward to meeting you when you get to the Philippines.
Philip
Jay Kantola 65ft trimaran
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Old 12-07-2017, 08:21   #83
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Re: No love for trimarans - why?

Pbmaise, is that the Kantola from Ventura, California? That is a very nice boat and seemed really strongly built. I was aboard a few times when it was in Oxnard being finished and got a blow by blow commentary of the launch on the phone from my dad while I was at work in Scottsdale.
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Old 12-07-2017, 22:00   #84
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Re: No love for trimarans - why?

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Pbmaise, is that the Kantola from Ventura, California? That is a very nice boat and seemed really strongly built. I was aboard a few times when it was in Oxnard being finished and got a blow by blow commentary of the launch on the phone from my dad while I was at work in Scottsdale.
Yes it is. It is also a good example of why so few big trimarans are around. It took 8 years to build. It is so much quicker to build one custom hull or two nearly identical ones. All three hulls of a big trimaran are quite different and there are six connection arms (aka) to build and attach.



No one really committed to making the bigger ones in fiberglass until Neel came along.
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Old 12-07-2017, 22:51   #85
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Re: No love for trimarans - why?

I owned a folding tri. The appeal to me was the relatively lighter weight for trailering, wider deck when cruising and greater speed potential. Indeed these were all benefits at times. However compared to monobulls I've owned, it had much less interior space for length. It was very fast in protected waters but the under deck slamming in even moderate seas greatly limited cruising potential. Rigging was time consuming and dangerous. Few ramps could accommodate the depth and width. It was very sensitive to weight. A few weeks basic provisions were really pushing it. After one trip to the Bahamas, I sold it and returned to monohull sailing. I love cats in the 35-40 foot range, but don't like the price.
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Old 13-07-2017, 16:58   #86
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Re: No love for trimarans - why?

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Whharram's opinion was wrong, is wrong, and is simply a bunch of nonsense. He was primarily arguing that multihulls in general have (as of 1990) become to powerful and people should go back to slower boats. In no small part this is because his designs use lashed beam fittings instead of solid ones (functionally the same as tying a keel on instead of bolting it down) and so couldn't handle the loads applied by larger rigs. But what this has to do with modern designs I have no idea.

Having sailed large cats, large trimarans, and large monohulls (all over 70') I would always choose a trimaran for sailing performance, a cat for anchoring comfort, and a monohull for carrying lots of stuff. Given the preference and someone else's money I would always choose a large trimaran over the other two.
I own a big trimaran and bought into the big mast concept.

Let me say there are racing trimarans and there are cruising trimarans.

I now sail with a much smaller sail plan and can tell you as a cruising sailor how much more enjoyable it is to me as the owner and person responsible for paying the bills.

You really hit the nail on the head when you wrote "someone else's money".

I have met other trimaran owners that were also encouraged by others to spend their money and go big.

When your vessel is 40 feet wide and loaded down, a strong gust of wind must be resisted. Think of that sail like an 8 story tall building. It stands without spilling the wind.

The original couple that built my rig told me they were terrified of it. I found the sail locker full of blocks which had been pulled apart by the rig despite being the largest and most expensive available in the West Catalog.

It is my opinion that had more big trimarans been built with smaller low maintenance rigs as James Wharram advocates, there would be a lot more happy big trimaran cruising sailors.

I want to speak about shock loads and g forces. Besides the lack of heeling, fully understanding how severe the shock load and g forces are on a big trimaran is critical in standing rigging design.

I have found the most damaging sea conditions are not big waves. Instead they are rather small waves about 1 to 1.5 meters high that are spaced close together and beam on.

The entire vessel can be thought of as a teeter totter.

Imagine a small sharp wave approaching the starboard ama. When the peak arrives, the starboard ama is lifted high, the vessel tilts, and the port ama is depressed into the sea and resists the tilt.

When the wave moves toward the central hull (wa'a) support under the ama suddenly disappears. Gravity pulls the ama downward, and the water pressure on the port side compounds the motion since it was depressed into the sea.

When the wave passes under the wa'a and reaches the port hull, it raises the port ama and depresses the starboard ama into the sea. There is then a sudden tilt when the wave clears the port ama and it drops.

Where the big problem comes is the spacing between short waves. With multiple waves and a wide trimaran, the waves can be sequenced so that the wave that picks up the port ama arrives just as a wave clears the starboard.

When this condition occurs, the starboard ama is depressed down into a valley. Momentum from the pull of gravity depresses it further. Weight in the ama from sails and outboards is not a friend here. I believe it is for this reason that accommodations and weight in most trimarans in the ama is minimized.

After an ama is depressed down into a valley, the next wave that hits tends to slam against the side and lift it more quickly.

You really have to be aboard and watch as this occurs. The shift from leaning to starboard to leaning to port are sudden and exaggerated when waves line up the wrong way.

Weight aloft and mast height determine how much load the standing rigging must withstand under these conditions.

Monohulls and catamarans also experience g forces on their masts as they rock back and forth. However, it is my position that they do not experience them to the same degree.

Therefore, big cruising trimarans:

#1 Are over rigged because they can easily support a tall mast and people like to go fast.

#2 Face huge loads because they don't heel.

#3 Face more g forces because of this teeter tottering.

To help over come the shock loads on my standing rigging I introduced some flexibility. I basically pluck the two main backstays with a flexible line that incorporates a spring. When there is a sudden pull on either windward or leeward the spring absorbs most of the shock load. Until I made this change, after every sail I found my Dyneema backstay lines had stretched.

Before this change, I also lost a mast. The sea state was as I have been describing and I had no canvas up. The rigging part that shattered was rated for 25,000 lbs safe working load.

Many claim that had I been flying canvas that the mast would not have created these loads. I agree in part. If I had enough canvas up, the windward hull would have been clearing the waves since it would have been flying. However, how many cruising sailors fly enough canvas in 30-40 knot winds at night to fly their windward hull? Those pictures of trimarans flying their hulls are pretty. However, who except a professional racer flies their hull at night?

I don't think a small amount of canvas would have helped reduce g-shocks either. The loads owing to the the two ama suddenly dropping would still occur.

Oh well. Time for me to clean the bottom. I have roughly 62 feet times 6 feet of water line to clean.

Overall, had I begun my sailing adventures aboard my trimaran with the much smaller sailing plan and Wharram height mast that I currently have, I would have had a much more enjoyable cruising experience.

True, I will win no races at 10 knots. However, that speed is now fine for me and I can sleep easily knowing I have a much safer controllable rig.

Winning races on a trimaran is only fun if you are using "someone else's money".
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Old 13-07-2017, 18:23   #87
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Re: No love for trimarans - why?

Quote:
Originally Posted by pbmaise View Post
I own a big trimaran and bought into the big mast concept.

Let me say there are racing trimarans and there are cruising trimarans.

I now sail with a much smaller sail plan and can tell you as a cruising sailor how much more enjoyable it is to me as the owner and person responsible for paying the bills.

You really hit the nail on the head when you wrote "someone else's money".

I have met other trimaran owners that were also encouraged by others to spend their money and go big.

When your vessel is 40 feet wide and loaded down, a strong gust of wind must be resisted. Think of that sail like an 8 story tall building. It stands without spilling the wind.

The original couple that built my rig told me they were terrified of it. I found the sail locker full of blocks which had been pulled apart by the rig despite being the largest and most expensive available in the West Catalog.

It is my opinion that had more big trimarans been built with smaller low maintenance rigs as James Wharram advocates, there would be a lot more happy big trimaran cruising sailors.

I want to speak about shock loads and g forces. Besides the lack of heeling, fully understanding how severe the shock load and g forces are on a big trimaran is critical in standing rigging design.

I have found the most damaging sea conditions are not big waves. Instead they are rather small waves about 1 to 1.5 meters high that are spaced close together and beam on.

The entire vessel can be thought of as a teeter totter.

Imagine a small sharp wave approaching the starboard ama. When the peak arrives, the starboard ama is lifted high, the vessel tilts, and the port ama is depressed into the sea and resists the tilt.

When the wave moves toward the central hull (wa'a) support under the ama suddenly disappears. Gravity pulls the ama downward, and the water pressure on the port side compounds the motion since it was depressed into the sea.

When the wave passes under the wa'a and reaches the port hull, it raises the port ama and depresses the starboard ama into the sea. There is then a sudden tilt when the wave clears the port ama and it drops.

Where the big problem comes is the spacing between short waves. With multiple waves and a wide trimaran, the waves can be sequenced so that the wave that picks up the port ama arrives just as a wave clears the starboard.

When this condition occurs, the starboard ama is depressed down into a valley. Momentum from the pull of gravity depresses it further. Weight in the ama from sails and outboards is not a friend here. I believe it is for this reason that accommodations and weight in most trimarans in the ama is minimized.

After an ama is depressed down into a valley, the next wave that hits tends to slam against the side and lift it more quickly.

You really have to be aboard and watch as this occurs. The shift from leaning to starboard to leaning to port are sudden and exaggerated when waves line up the wrong way.

Weight aloft and mast height determine how much load the standing rigging must withstand under these conditions.

Monohulls and catamarans also experience g forces on their masts as they rock back and forth. However, it is my position that they do not experience them to the same degree.

Therefore, big cruising trimarans:

#1 Are over rigged because they can easily support a tall mast and people like to go fast.

#2 Face huge loads because they don't heel.

#3 Face more g forces because of this teeter tottering.

To help over come the shock loads on my standing rigging I introduced some flexibility. I basically pluck the two main backstays with a flexible line that incorporates a spring. When there is a sudden pull on either windward or leeward the spring absorbs most of the shock load. Until I made this change, after every sail I found my Dyneema backstay lines had stretched.

Before this change, I also lost a mast. The sea state was as I have been describing and I had no canvas up. The rigging part that shattered was rated for 25,000 lbs safe working load.

Many claim that had I been flying canvas that the mast would not have created these loads. I agree in part. If I had enough canvas up, the windward hull would have been clearing the waves since it would have been flying. However, how many cruising sailors fly enough canvas in 30-40 knot winds at night to fly their windward hull? Those pictures of trimarans flying their hulls are pretty. However, who except a professional racer flies their hull at night?

I don't think a small amount of canvas would have helped reduce g-shocks either. The loads owing to the the two ama suddenly dropping would still occur.

Oh well. Time for me to clean the bottom. I have roughly 62 feet times 6 feet of water line to clean.

Overall, had I begun my sailing adventures aboard my trimaran with the much smaller sailing plan and Wharram height mast that I currently have, I would have had a much more enjoyable cruising experience.

True, I will win no races at 10 knots. However, that speed is now fine for me and I can sleep easily knowing I have a much safer controllable rig.

Winning races on a trimaran is only fun if you are using "someone else's money".
Wow, that was a very informative piece. I look forward to meeting you when I get to the PI later this year. A 65' Kantola sounds like a beautiful boat.

I agree on the shock loads. I try to keep my speeds below 9 kts, 7-8 is comfortable, The boat will do 20 in the right conditions but then one is only doing 20 until something breaks (and it will) and they one is doing 1-2 kts.

Agree the the more sail plan not being necessary on a cruising tri but I also think a huge chunk of typical passage times are met with zero to light winds and it's those time you find yourself wishing you have all the sail in the world (unless you like running your motor). I was on a passage once where the apparent read 0.0 yet I was able to do 5.5 by putting the chute up and gybing back and forth to create my own apparent wind. I did that for 3 days until I reached the trades again. It was either that or motor.

I also have Dyneema rigging and I also notice "creap" in my backstay. I use that word because John Franta of Colligo Marine told me it's definitely creap going on and not stretching. So I have to adjust the lashings after a hard sail. But it kinda freaks me out because I'll see the top of the mast pulling forward in such situations. Do have any pics of your shock-line/ spring setup for your backstay? That's a brilliant idea!

I've definitely experienced the g-force teeter-tottering. I agree it's very sea state dependent. Sometimes it can be so amplified to the point that I find myself thinking, "is a monohull a better ride?" But then I remember a saying a cruiser told me a few years ago: "Everyone whines about passages at some point. Most are short, only take 6 days on average. 80% of a boats life is spent on the hook." His point being make sure you don't compromise on-board living and accoutrements at your destination for performance at sea. So for me if the sea state gets too gnarly where the teeter-totter really starts to bother me than I'll slow down a bit. Most times that resolves it but it can only be minimized so much so I just have to get use to it. Fortunately, the builder of my boat didn't cut any corners so despite her being light (for a large curising tri), she is strong.

I also think the 200% buoyancy design exacerbates this issue. That is, each ama supports 2x the weight of the entire boat (unloaded), so as that windward ama gets pushed up by the wave, that leeward ama's extreme buoyancy is, by design, fighting the downward force, when that same waves gets to that leeward ama it's already shooting back up towards the surface so the result is sort of a hobby-horse/ herky-jerky ride. Oh well, I get use to it... to a point where I don't really notice unless I'm thinking about it.

There are trade-offs in any design, any boat. I'm pretty happy with the balance of it all in my boat. Lots of space, storage, 5 different areas to lounge out on deck (the nets, the bows and wings, forward of the pilot house windows, the cockpit wings and the aft deck) makes entertaining pretty painless. I can store two dinghies and a small sailboat on deck for passages without getting in the way of anything (for local sailing I keep those boats on davits).

Now if I had money to burn, I'd go with the new Neel 51. But I have my kid's college bills on the horizon so that dream will have to wait.
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Old 13-07-2017, 18:31   #88
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Re: No love for trimarans - why?

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Captaingregger

That's great but what design and size ?
Horstman Tristar 45. Sloop vs cutter as he originally called for and extended to 47 with the bow sprit and outboard track add on.

Once she arrives to Cebu for the refit work I'll probably add 5' to the stern for steps and a sugar scoop. But we'll see.
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Old 13-07-2017, 19:28   #89
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Re: No love for trimarans - why?

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I am glad you like your Tristar - they are commodious tris.

You have to be careful talking of capsize and heel. Tris usually have a lower CG which means they can heel more (probably about 70 degrees) before becoming negatively stable. A cat may be a few degrees less but it depends on bridgedeck height and loading. What we do know is that both tri and cats are on the wrong side of the stability curve once the tris main hull, and the cats windward hull, lifts.

One area that tris do better, and worse, than cats is with rotational momentum. The lighter extremities of most tris means that they have less rotational momentum. Cats on the other hand with two weighty hulls at the extreme beam have more. This is one reason tris are more nimble. It is also one reason why tris are more prone to wave capsize when abeam to waves. Think of having 10kg of weight at the centre of a pole. You can wiggle it easily, Put two 5kg weights at each end and rotating the pole becomes much harder.

James Wharram once got confused when talking of tris vs cats. He said that because some racing tris heel at anchor it makes them closer to capsizing. In reality you just have to go back to a diagram showing the CG and CB. The higher initial heel of a tri makes little difference to the CG and CB so it still takes the same amount of rotation to capsize a tri with a high float as one with the float in the water

cheers

Phil
Interesting points. I am relatively new to multihulls (2 years) although I have a pretty extensive sailing resume. My father raised me on boats. Summer breaks were spent on open ocean passages and I eventually became a locally-sponsored racer and sailmaker before I realized there wasn't much money in it (well, back in the 80s anyway) and decided to focus on a career in aviation instead. I do pretty much all windsports to this day (sailing, racing, kitesurfing windsurfing, foiling) and yet becoming a multi-hull owner has been a steep learning curve despite my extensive experince on the water and using the wind for propulsion. A lot of what I though I knew really doesn't apply to multi-hulls and a lot of multi-hull information out there is based on cats not tris so it doesn't always apply to what I'm looking for. Hence I appreciate all added information to these discussions. Keep it coming!

In the case of my tri, the amas are much heavier than comparably size cruising tris and they don't tend to fly. I have never flown one and the previous owner/ builder claims he never flew one in 23 years of sailing her (is that a good thing or a bad thing?). Therefore I'm not sure how much of this applies. Now factor in the 200% buoyancy in the amas and that means in an extreme heel situation the leeward ama is at least somewhat fighting the heel as it inherent buoyancy wants to fight downward force as it displaces water. I'm not saying it can't happen or that the boat could not flip. I'm just pointing out that by design Horstman's much heavier designs make capsize less likely than say a racing tri counterpart. Of course the trade off is speed and performance. But as I've said in previous posts that is something that I can live with. These days I'm all about getting there in style. For my adrenaline fix I charge 20'+ waves doing strapless wave-kiting (surfboard w/o straps vs a traditional strapped-in kiteboard). By the time I'm out on the water cruising on my boat I just want to chill.

To my knowledge, a Horstman Tristar has never capsized. Again, to my knowledge only. I'd really love to hear someone counter that point, because if one has turtled I'd love to know, but I researched this EXTENSIVELY, as did the previous owner/ builder. By contrast, in my research, I counted 78 multi-hull capsizes over the past 20 years. I'm sure there are more but that's all I could come up with after spending weeks searching for such data on the internet. I wanted to learn from their experiences. Very few were cruising multis. Most were racing or pushing it in a rather ignorant manner but none were of the Horstman design. Again, I'm not saying it can't happen. I think someone trying to sail through a Cat 5 typhoon in one is sure to flip unless deploying a robust parachute anchor system. But if I were caught out in such a storm, God forbid, I'd be more infinitely more worried about the boat breaking apart than capsizing.

The guy I bought the boat from, he built her, was in Cat 2-strength conditions in the southern ocean. Winds were 90+ kts on the meter. Seas were 40'. He did not deploy a parachute anchor nor a drogue. He was ready to but said it was just too hairy and thought he might get yanked overboard by a wave. I asked him if he was scared. He said, "yeah, for the first 24 hours of it (the storm lasted 3 days). But after that I realized she was doing what she was designed to do." He went on to tell me that on some waves the rudder would lose traction and the boat would slide completely sideways down the wave face. When she got into the trough the rudder would re-bite and she'd correct course. He said she was often doing 20+ kts down those wave faces. SCARY in my boat and this is coming from a guy who's seen numbers in the regular 30s while racing maxis.

He built the boat WITHOUT daggerboard, even got into a fight with Ed Horstman about it. Ed actually told him when he asked him to design in a short skeg keel into the main hull, "nobody's putting a keel on my boat!" To which Jack replied, "it's not you effing boat, Ed!" They never spoke to each other again. Instead he hired Norman Cross to design in a keel. Norm had died by then but before his death he designed keels for every Horstman design so his wife kindly sent jack the plans. So even with a keel, she'll slide sideways down a 40' wave face, it's been proven. Mostly because the keel depth is quite shallow. I forget it's actual depth, maybe 12". The boat itself draws just under 4'.

That said, I'm told the waves of the Southern Ocean are gradual and rather predictable vs the voodoo chop we get in the Western Pacific. So wave period and height has a lot to do with how steep that mountain of water can become, thereby affecting the the ride in typhoon-force storm. I'd take a 40' Southern Ocean wave vs a 20' Western Pacific wave with a shorter period most times. But add in 90 kt winds and I'm not sure I would say the same thing.

I think the keel being more of a shallow skeg-type than a deep draft keel is what allowed her to slide with the wave then correct in the trough rather than act as a pivot or tripping point that an ama daggerboard would presnt (of course nobody in their right mind would keep the daggerboard down in such a storm so the point is probably moot). Weirdly, it's still deep enough to give me the upwind pointing and tracking ability that I would likely get with daggerboard. I wonder if that has to do with that fact that it runs almost the entire length of the main hull to the prop shaft. So while it's not a deep keel it is a long one thereby covering more surface area.

Another Horstman 45 I looked at had a similar story except that he was off Bermuda and a monohull 1 NM behind him rolled twice. In the second roll the husband of the of couple broke his back and the wife a may-day call. He and his crew decided to turn around in 110 mph winds and 33' seas. He said it took full throttle on the motor to get through the tacks upwind in those conditions. They beat to weather under sail and engine for tacks for 3 hours (just to get 1 mile upwind) and circled on station until the USCG arrived in the morning. He said the boat took such a pounding that he thought for sure he'd find damage throughout the hull when they got to the Bahamas. His words, "Not one shred of evidence of damage, not even a spider crack in the gelcoat." He said speeds were so high and they were so out of control on the downwind runs in that storm that they trailed two drogues, tires wrapped in chain to slow down. BTW, that Horstman did have daggerboards. That owner survived two hurricanes in his Horstman (named "Desiderata"). Beautiful and tested boat for sure!

A part of me regrets not buying it when I had the chance. I'd love to know where she is today if anybody comes across her, a 1997 Horstman Tristar 45, named Desiderata.

Stories like that, and because of my childhood dream to own one when I laid eyes on my first Horstman, I think it was a 55 or 60' (Trilogy of the charter company on Maui), are why I stuck with the Horstman design in my search for the right boat. It took me 6 years but eventually I found her.

As I've said in past posts, I would LOVE to own a new modern cat (2015-17 design years). But sailing/ cruising isn't my only passion so I can only allocate so much money towards it at this stage in life. We're still raising kids and young adults, love to travel, and still do a fair amout of RVing Stateside. For the price point that I got my trimaran, and the requisite insurance and mx costs, along with refit/ remodel ambitions, I think I'm in the right place. At the end of the day we are all out to accomplish the same thing, get out on the water and enjoy sailing. Whether you spend $4 million on a dream yacht or 1/20th that price. Pretty much any well-maintained and clean boat (mono, cat, or tri) will accomplish that same goal.



Quote:
Originally Posted by SailFastTri View Post
I call BS (to the portion I bolded) -- you're making this up or you read some pseudo science somewhere. Show me the calcs. Buoyancy in the amas is a design - specific thing and should not be generalized. Racing tri's and cruising/sport tris (such as the Dragonfly boats) have adequate ama buoyancy that renders your statement untrue.



"Grip"? I have no idea what that's about. Yes, all hulls have some drag, but to cite about the difference in water speed between a wave's windward and lee side as a capsize factor from hull drag is incredible.

I've owned 3 Dragonfly tri's (a 920, 100, and 1200) since 2001 and I think your two posts above sound implausible. Warram might be misunderstood, misquoted, or perhaps he was just wrong if he wrote that. I'm not trying to pick a fight, but I don't think the views you expressed should go unchallenged.
I have to agree with you here, SailFastTri. And I'm coming from a cruising tri point of view vs a fast/ racing tri point.
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Old 14-07-2017, 09:23   #90
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No love for trimarans - why?

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Originally Posted by pbmaise View Post
.



Many claim that had I been flying canvas that the mast would not have created these loads. I agree in part. If I had enough canvas up, the windward hull would have been clearing the waves since it would have been flying. However, how many cruising sailors fly enough canvas in 30-40 knot winds at night to fly their windward hull? Those pictures of trimarans flying their hulls are pretty. However, who except a professional racer flies their hull at night?".


Huh? Your experiences are a lot different than mine.
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