proas?

[kjbsail]

Anyone know of any succesful cruising proas? Or better yet, have experience sailing on one? Any proa relevant links, opinions etc. would be appreciated. Thanks

[Jeff H]

There seems to be a lot if interest in Proas lately. There was a discussion of proas on the Yahoo LowCostCruising group just yesterday. There are two distinct types of Proas that are generally described as either Pacific (or flying) or Atlantic (which keep their ama to leeward). The difference between the two types relates to the side of the main hull that the ama occurs, Pacific proas carry their ama to windward and Atlantic carries theirs to leeward. Atlantic Proas are generally considered better suited for offshore passage making. Pacific Proas are far less suitable for voyaging as they take constant vigilance to keep them moving and not capsizing. Dick Newick's Atlantic proas have been very successful in long distance passage making with many transatlantic crossings to their credit. They are a well-developed concept that makes a lot of sense if your goal is to cross an ocean.

They have just one big shortcoming and it is huge. You can't tack or jibe them quickly or in tight quarters. To change tacks in either kind of proa, you bring the boat to a stop beam to the wind, rotate the masts and sails from facing forward in the old tack to facing forward on the new tack, raise the previous aft rudder and lower the aft rudder for the new tack and then race off in the direction that you came in. It takes hundreds of feet to dead stop even a small proa and a lot of leeway to get one going again. That works fine in the open ocean but would make sailing in close quarters nearly impossible. Also proas use freestanding rotating rigs (typically wing masts) with duplicate sheets in both directions which are quite expensive to build and can be a problem in heavy winds when you need to depower completely.

There are other problems as well. Proas really need to be light in weight. More so than most multihulls because without the ability to feather up or go head to wind, they handle gusts dissipating the force of the gust by accelerating rather than heeling. Caught dead in their tracks they are a lot more prone to capsize than when they are at speed. They become dangerous if you load them up with a lot of heavy gear, which you would if you would tend to do when voyaging. If you are concerned with budget the extreme light weight gear found in performance proas are more expensive to buy and when you are voyaging you would want to 'stock up' on supplies when you can buy them cheaply and carry them with you to places or times were they are expensive.

To a great extent, Tri's and Cats make a lot more sense than proas if you are going the multihull route. They are approximately the same cost to build, offer a little better load capacity and are much more maneuverable in tight quarters.

Respectfully,

Jeff

[Steve Rust]

Russ Brown is one of the better known authorities on proas. An internet search using the names Jzero, Cimba,Kauri, proa , or Russ Brown should turn up something. A few years ago Cruising World had an article about Russ and Steve Callahan sailing his latest boat Jzero to the South Pacific. Woodenboat also featured Russ and his proa Kauri on the cover quite a few years ago and had a very good article starting with the first Jzero that Russ built as a teenager for $400 and sailed to the Virgin Islands from Virginia. I understand that he is reluctant to sell plans to others as these boats require a skilled hand to sail them offshore. They are quite interesting boats and strikingly beautiful. The articles about Russ and his proas are a great read. He uses the Pacific style proa with the ama to the windward side. By the way Russ is the son of Jim Brown the Searunner Trimaran designer.

Steve R

[Steve Rust]

Try this web site www.wingo.com/proa/links.html
Lots of proa links.

[cat man do]

Rob Denny is doing these and they appear to be a good thing.

Harryproa Home Page



Dave

[yotphix]

Not to hijack but I'm curious what advantages something like that has over a cruising cat. At first glance it seems rather silly! Hard to imagine what storm tactics would consist of other than hoping the wave heights never exceed the beam.

[DtM]

Rob Denny is definitely the man for you to contact.

I have his email address if you want to PM me.

[rob denney]

quote=Jeff H]There are two distinct types of Proas that are generally described as either Pacific (or flying) or Atlantic (which keep their ama to leeward). The difference between the two types relates to the side of the main hull that the ama occurs, Pacific proas carry their ama to windward and Atlantic carries theirs to leeward.

Rob
There is a third type, which are Harryproas. These combine the best features of both the Pacific and Atlantic types. For a discussion of this, see http://www.harryproa.com/Newsletters/news4_hg4.htm (the first part is general proa background, the harry stuff starts half way through)

Jeff
They have just one big shortcoming and it is huge. You can't tack or jibe them quickly or in tight quarters. To change tacks in either kind of proa, you bring the boat to a stop beam to the wind, rotate the masts and sails from facing forward in the old tack to facing forward on the new tack, raise the previous aft rudder and lower the aft rudder for the new tack and then race off in the direction that you came in. It takes hundreds of feet to dead stop even a small proa and a lot of leeway to get one going again.

R Not so. I could stop my 12m/40' proa in a couple of boat lengths. The fastest shunt I did in that boat was 8 seconds from full and bye on one tack, to sailing on the other. There is a light air video of my smaller proa shunting at http://www.harryproa.com/ShuntingVideo/Shunting.htm Leeway to get going is negligible as the boat is luffing as it gathers speed. If the rig is balanced (ballestron), the sheet loads are minimal, a single part mainsheet will do the job. Dumping this and sheeting it back in are far easier and safer than tacking a jib. The rudders rotate through 360 degrees, and will rotate on their own when the boat starts sailing in the opposite direction. It is far easier than tacking, has no possibility of getting caught in irons and can be reversed at any time. This has safety implications as well. I can get back to a man overboard far quicker than any other sail boat, and stop, with control in either direction, exactly where required.

J That works fine in the open ocean but would make sailing in close quarters nearly impossible.

R I regularly sailed up and down between marina arms. Directly upwind one way, ddw the other. A similar size mono or cat would not have a chance of doing so fully crewed, much less solo.

J Also proas use freestanding rotating rigs (typically wing masts) with duplicate sheets in both directions which are quite expensive to build and can be a problem in heavy winds when you need to depower completely.

R Our carbon freestanding rigs are much cheaper than alloy masts and rigging. Depowering in heavy air could not be easier. Release one lightly loaded rope, the rig weathercocks and the boat stops, on ANY point of sail. No other sail boat can do this.

J There are other problems as well. Proas really need to be light in weight. More so than most multihulls because without the ability to feather up or go head to wind, they handle gusts dissipating the force of the gust by accelerating rather than heeling.

R You are correct about the weight. A 15m/50' Visionarry Sport design was launched in Holland last year. http://www.harryproa.com/visionarry.htm It weighed 2 tonnes/tons ready to sail. It contained 2 huge double berths, plus a single, a large galley and nav station and a covered cocckpit for 8 people. It was built from glass and cedar. A stripped out racing tri in carbon and nomex weighs twice as much. Lower weight means lower cost and less work to build. The unstayed masts dissipate gusts extremely well. With all the weight of crew and gear in the windward hull, harryproas have way more righting moment than cats of similar weight and beam.

J Caught dead in their tracks they are a lot more prone to capsize than when they are at speed. They become dangerous if you load them up with a lot of heavy gear, which you would if you would tend to do when voyaging.

R Harrys do not become dangerous, they become safer, up to their design weight. After that, extra stuff is stowed in the leeward hull. They then get slower, but are just as safe.

J If you are concerned with budget the extreme light weight gear found in performance proas are more expensive to buy and when you are voyaging you would want to 'stock up' on supplies when you can buy them cheaply and carry them with you to places or times were they are expensive.

R Harryproas are the cheapest boats available for their speed or accommodation. There is little or no metal on them, the few fittings that are required are all built from composites and can be owner built.

J To a great extent, Tri's and Cats make a lot more sense than proas if you are going the multihull route. They are approximately the same cost to build, offer a little better load capacity and are much more maneuverable in tight quarters.

R No, no and no. For the reasons stated above. Where are you situated? There are 30 harrys (from 7.5m/25' to 20m/66' being built from Tasmania to northern Norway. If you are interested, I will try and organise a sail for you.

Regards,

Rob Denney
www.harryproa.com

Respectfully,

Jeff[/quote]

[rob denney]

Originally Posted by yotphix

Not to hijack but I'm curious what advantages something like that has over a cruising cat. At first glance it seems rather silly! Hard to imagine what storm tactics would consist of other than hoping the wave heights never exceed the beam.

G'day,

Try a second glance!

The main advantages are
Weight; Half as much, see previous post re 15m cruiser
Cost: A little more than half as much
Comfort: The crew always sit to weather, in comfort with excellent vision of the sails and horizon. Crew weight is in the centre of the boat, so pitching is minimised. The cockpit, galley, nav station and accommodation are always to windward Sail handling is far easier and less onerous than a stayed rig.
Safety: shunting involves no flogging sheets, winches or whizzing travellers. "Tacking" and "gybing" are completely safe and reversible in all weather.

Storm tactics are similar to a cat, except that the transformation from running under bare poles to heaving to with a parachute does not involve luffing the boat head to wind, arguably the most dangerous part of deploying the parachute. Because they are so light and have retractable rudders (oversize, no centrboards required) the water foils can be lifted making the boat into a very shallow (300mm/12" on the 15m/50'ter) raft. Capsizing this by waver action would be difficult, if not impossible.

regards,

Rob

[cchesley]

What I also didn't see Rob mention is that the whole structure is so much lighter because you don't have to design and build with consideration to rig tension. Rob, I have followed your progress for a number of years and have to admit that from a technical standpoint, you've got a good thing. I can't get my wife (okay, me neither) to embrace the aesthetics. I'd also like to see a bit more about how they are working in practice. It was regrettable that one of your owners didn't have the chance to put his new boat through its paces. How are the others doing? I continue to try to figure out another way to do the rudders/foils. They seem so vulnerable but have yet to find a solution. I know that they have been the biggest challenge overall.

Aside from weight, what are the disadvantages of making the WW hull more equal tothe LW hull in length. (I'm thinking aesthetics here, mostly)

[44'cruisingcat]

Great info Rob. Looks like Proas have something in common with every other type of multihull - Aussies do them best!

[rob denney]

Originally Posted by cchesley

What I also didn't see Rob mention is that the whole structure is so much lighter because you don't have to design and build with consideration to rig tension. Rob, I have followed your progress for a number of years and have to admit that from a technical standpoint, you've got a good thing. I can't get my wife (okay, me neither) to embrace the aesthetics. I'd also like to see a bit more about how they are working in practice. It was regrettable that one of your owners didn't have the chance to put his new boat through its paces. How are the others doing? I continue to try to figure out another way to do the rudders/foils. They seem so vulnerable but have yet to find a solution. I know that they have been the biggest challenge overall.

Aside from weight, what are the disadvantages of making the WW hull more equal tothe LW hull in length. (I'm thinking aesthetics here, mostly)

G'day,

Apart from the boats I have built (3 lee hulls, 4 windward hulls, a couple of rigs and beams and untold rudders) there has only been the 15m mentioned above (owner died after 2nd sail) and a 12m which has just been launched and has yet to do any serious miles.
Generally speaking, everything works as it should. If we had stuck with rudders that have all the drawbacks of most other rudders (can't be lifted, don't kick up in a collision, require a hole in the boat) we would have been fine with the original rudders, which worked very well. We have tried to overcome the problems of conventional rudders and have had a few problems. However, these seem to be sorted, and we have rudders that do not require holes below the waterline, can be steered in 300mm deep water and kick up in a collision. They also work in both directions are big enough to not need daggerboards.

Longer ww hulls are heavier/more expensive, draggier and impart more twisting loads to the beams. The space in the ends is pretty hard to utilise and is not the best place for weight. The aesthetics take a bit of getting used to, but for proa people, the advantages of the form outweigh the looks.

regards,

Rob

[fhrussell]

Quickly, ... In regards to the cost of proas:

As a teen, I was building proas and outriggers because they were the most affordable way for me to build a boat and get out on the water! Once I had an adult income, then, and only then, could I afford a catamaran.

Also, shunting a proa requires alot less room than you'd imagine, as stated by Rob. Because the boat is so light there is not alot of kinetic energy to keep it moving thru the water like a mono. It stops fast when the pressure is released from the sails. A properly designed rig can be very fast to shunt, as the Harryproa's show.

[dana-tenacity]

Aesthetics, I was aboard Rob's 50 ft proa last week and it is the sexiest thing on the planet besides my wife.