I found the SC17 to be a lousy beginners boat. Nothing for the crew to hold on to on deck. sharply rounded decks very uncomfortable to sit on. The only time i had a crew get hurt badly was on one in a lake. the boat dived the bows under sharply and quickly and came to a sudden halt when the massively draggy main beam hit the water. With nothing to hold on to the crew injured her knee after being flung forward.
My friends wife also hurt her back when they tipped over. nothing for her to hold on to.
I theorize that the forward canting rudders have something to do with the bows of the supercats wanting to dive all the time.
Also the 17 was meant to be a 2 up boat when first sold. that's why they made a 15 for 1 person. There are boardless boats from many builders that can be sailed by 1 that were originally designed for 2.
My memory of the symetrical boardless cat evolution of the 70s-80s is as follows.(not including the kind with fins-dart type)
Sizzler-aluminum hulls
G-cats
Supercats
Trac 16
The Trac 16 was an improvement over the Supercat IMHO.
There was nothing faster than a G5.7 off the wind in the days before the assy. We worked our way up to top 3 once at Texel on the downwind after a mediocre start.

The whole point comes down to the fact wether the ARC products are fast because of efficiency or because of the huge rigs they feature. The problem here is that without having a really comparable design using the "normal setup", it's hard (if not impossible?) to tell wether any speed increase is the result of superior efficiency or just the result of having a bigger engine.

Last year the Dynacat F18 (with planing underside, hard chines, and step) was launched; it didn't make an impression in the F18 class and wasn't seen to beat the "normal" F18 designs. Therefor the conclusion is simple. Now assume that the builder Mattia had put 20 % more sailarea on it, reduced the weight and made it wider as well all resulting in a boat that was a somewhat faster than a standard F18. But how much of the increase in speed was the result of the sailarea, etc and how much of the planing hull ? It is very possible that the planing surface made the hull less efficient and therefor slower while the increase in sailarea, etc was still enough enough to still make the overal design faster. We would never know without a proper reference boat. And the ARC product line is so off in specifications that there is simply no reference boat for any of them.

It appears that all ARC's are underrated in PN despite any outcome of the question above. Bill claims the designs are surprisingly fast in various posts as others, like you, do as well. The SC's are so much more efficient and fast ? Than why is Prindle 18 = 74.5 ; when SC-17 with 13 % more sailarea on taller rig = 73 = 2 % faster. Note also how the SC-17 = 73 = only 4 % faster than a H16 = 76.1 while the SC has no less than 15 % more sailarea than the H16. If anything; the ratings of the SC-17 are remarkably unimpressive considering the rig that sits on it.

Note that the sailarea's of the H16 and P18 are as good as identical. The weigths of both boats are relatively close as well. Increases in waterline therefor can only account for some 2 % speed increase. Please also note that the OLD SC-17 has more sailarea than the F18 = 63.5 as well. So somewhere a significant portion of all that power is lost in order to arrive to ratings that are 11% (spi) to 15 % (no spi) apart. This actually signals inefficiency !


So what is it ? You can't be more efficient and alot slower at the same time. Are the ratings correct and is the setup less efficient because the SC setup only achieves respectively 2 % and 4 % increases in speed for 13 % and 15 %increases in power ? Or is the setup more efficient in addition to having more sailarea and are the PN's are way off ?


The contradiction is not in the complaints but in the claims !

Therefor we can definately "have it both ways".

The refusal to adres this glaring contradiction and camouflage it with lenghty explanations using unprovable claims is the part I named :"smoke and mirrors"

The diaper comments fall fully under the smoke and mirrors description. Or else we must claim that Ellen McArthur can never win a race because she was still in diapers when all other Vendee Globe and mini sat sailors were already winning their first opti races.


Wouter

Your comments lead me to question if you ever stepped foot on a SC. I use to take my eight-year-old daughter, and 5-year-old son with me all the time on my SC 17. Never once did I lose either of them overboard, and they never lacked for something to hold on to. I never experienced “the boat dived the bows under sharply and quickly and came to a sudden halt when the massively draggy main beam hit the water.” My sailing was predominantly in the Atlantic Ocean out the Ft. Pierce, Inlet and along the beach. We are talking waves here… with heavy chop on top of the swells…the boat absolutely loved rough water.

The actions you described were quite common occurances for me when I sailed a Hobie 14…but I never experienced them on the SC17.

Bob

Wouter…my friend…I did not mean to be offensive in my diaper comment…only use it for dramatic effect in stating that it is ludicrous to say that a 23-24 year old boat is avoiding competition when it was designed, and in production just short of two decades before these new classes with their self determined rules even existed. It would be easier to argue that the new classes should have been built within the 17’ format ( SC 17/Hobie 17/Inter 17/Nacra 5.2).

Surly, you must know that a boat is designed around a whole group of variables…and only becomes a superior design when all are working in harmony for the intended purpose along the chosen design path…why then does every one keep insisting Bill Roberts take his well balance designs and bastardize them to fit into the latest manifestation of catamaran rules? If one of the designs were changed to fit the current trend and it suffered a performance loss, what would that prove? Nothing!…The boat was designed to work a certain way, in certain conditions, within certain physical perimeters.

If you reduced the sail area or beam to match that of another hull design that cannot carry as much sail because of pitch poll problems, have you proved anything? All you have done is limit a design, which has superior pitch poll resistance. And in effect excused the poor design on the new boat. Is this progress?

I would say the SC series has been kind of a reality check for those who have fooled themselves into thinking that catamaran design has made progress in "leaps and bounds" within the last 20 year time frame. It really takes the pizzazz out of marketing High Tech and/or High Performance classes when those pesky 20+ year old SC’s keep coming back from the grave with a few sail tweaks to beat the latest and greatest high tech wonders….

Why can't we have room for both...designs which are free from artifical restraints on length, beam, weight, sail area, and the "effeciency" design aproach within constrictive perimiters you are so fond of? Because when you look at the big picture, and the time line of catamaran design, it looks as if the F16, F18, F18HT, F20 classes are the new guys on the block crashing the party...not the other way around.

Bob

I think Wouter's comments were more along the lines of; if you really want to prove superior design elements, then design it within the arena of other existing designs. For example, if I build a go-kart that's twice as wide and has three times the engine against a standard, more conventional, go-kart and win - what have I proven? If I want to prove that my go-karts designs are faster, then I should build my go-kart within the current popular parameters. By all means, we should build the wide one if it will sell, but we can't really get excited about having superior design elements based on the fact that we're beating more conventional ones. To say that these boats should be a "reality check" to boats that are designed within different constraints is a bit of a stretch. If you took the SC20TR, lopped 4 feet off it's beam and 6' from it's mast such that it falls in the same category as the boats we seem to be claiming superiority over, things could look a bit differently. Where do you think an SC20TR would place racing boat for boat with a carbon Marstrom 20 (even though the Marstrom is still not as wide and doesn't carry as much sail area)?

Bill himself has indicated that the rating on the ARC17 is a bit soft and it's public knowledge that the rating on the SC20 is not very accurate (A Nacra 6.0NA owes a SC20TR, who's mast is nearly 6' taller and beam is 4' wider, time). The SC / ARC boats are more powerfull and faster than their ratings. So we can't really point to race results to say that one is better than the other. The standard for comparison is known to be faulty.

Don't get me wrong; I like the SC20 and the ARC series, I like the idea of a 12' wide boat, or experimenting with the boundaries of the shared lift concept, or adding more sail area to make it faster - but if these concepts are so revolutionary and successful, why don't we see a boat in the highly competative classes and formulas with these features? If it's really because all the other manufacturers are dumb, why don't we see an ARC conform to one of said classes to prove it? I guarantee that if a 'shared lift' ARC F18 was capable of outruning most other F18s it would sell like there is no tomorrow - ARC wouldn't be able to build them fast enough.

Why not constrain what really matters rather than putting artificial constraints on sail area or length? If you ask the wrong question you are unlikely to get the right answer.

1) Cost. The average annual cost over the lifetime of the boat is really important to many of us. Do I need to buy new sails every 2 years? What else do I have to replace on an annual basis? Will the hulls go soft after 10 years of hard sailing? Do I really need to pay an extra $2000 for carbon pre-preg hulls or can I spend $200 on a larger sail plan and go just as fast?

2) Real Performance. Is the boat still fun to sail through powerboat slop when the wind is gusting to 11 knots true? Can I make it home in one piece when the wind cranks up to 30? How wide is the range of conditions that the boat is fun to sail? Some of us have to plan our sailing days long before the weather forecast is reliable.

3) Setup. Can the boat be set up (from the trailer or cartop) by the number of people who will sail it - assuming one of them knows how to assemble it? Can this be done quickly enough to sail after work? If it is a singlehander - can you put it away alone in the dark?

4) Reliability and reparability. What is the mean time between failures that waste a good sailing day? If the boat gets holed by a floating log can I repair it myself?

5) Safety. Could the intended sailor be injured seriously as a result of the boat's design? Sure - some degree of risk may be accepted by the sailor. I would not want anyone to alter something that cripples to the performance of the boat just to make it safer, but don't build in booby traps.

6)Maintenance time to sailing time ratio. How many quality hours do I spend working on the boat versus sailing it?

7)Versatility. If the boat is designed for 2 can I still cruise with 3? Can I still sail it alone? Can the boat go racing one weekend and cruising with the kids and dog the next?

I want the fastest boat that is designed around these constraints, not some arbitrary number intended to limit performance but not cost.

colin pitts

I guarantee that if a 'shared lift' ARC F18 was capable of outruning most other F18s it would sell like there is no tomorrow - ARC wouldn't be able to build them fast enough.

Jake, you bring up great points...
Bill, it sounds to me like the gauntlet is out, fear not the challenge! Respect the outcome....

Hi Sam,
We are communicating better but still not totally.
It is no bull that the ARC17 has options of unirig or unirig plus jib or uni rig plus jib plus spinnaker. When you get to the order boat form, the orderer checks off the options they want even down to the color of the spinnaker.
Here is an example of our communications problem. When I talk about beach cats, I am talking about a small catamaran WITHOUT dagger boards; a boat you sail on and off the beach. To the beginning sailor dagger boards can be a real problem. Try coming in through even small surf with boards down. New sailors sometimes forget about the boards. I've seen it happen and sometimes it is not pretty. The ARC17 is a "keep it simple" boat. If you could see how it is rigged, I'm sure you would agree. Comparing it to a board boat is a non contest. The 17 is a boardless boat a with low aspect ratio sail plan. It is not intended/designed to be fast to windward. The 17 always has always been fast on a reach and downwind. This is the way beginning sailors like to sail. If they want to race at all, they want to drag race on a reach. The ARC 17 is not a racing boat, it is a beginners boat, a boat for people to learn how to sail on. Don't compare it to a racing boat because it is not a designed as a racing boat.
I took the ARC17 to the Tradewinds race for people to SEE IT. The boat has no US Sailing PN. It is a new boat. The best shot at a PN for the Tradewinds Race only was to use the SC17 PN and make adjustments for the things that are different between the SC17 and ARC17, boat width and sail plan. For the next race it sails in, I think a better number would be to take the last four heats of the Tradewinds and reverse engineer a PN for the ARC17 and calculate what the PN needed to be to make the ARC17 tie on corrected time with each one of the other boats in these heats. Then throw out the odviously high numbers, if there are any, and average the best of the low numbers. This should be a more correct PN number for the boat. This is how you get a correct PN for a new boat. This is the process in action.
You are right, Sam, there is no ARC17 class at this time. There are two boats in the whole world. You have to start a new class somewhere. When the class grows to ten boats or so, an association will be formed.
There is an ARC22 class organization with officers and race schedule and class rules etc. Every 22 that has been sold came with a book of class rules to keep the boat/sails etc class legal. A US National Championship Regatta is scheduled for this year. All SC and ARC boats are welcome.
The class has a web site with forums, etc.
All ARC products have class rules for platform geometry, rigging geometry, max sail sizes, etc.
I hope you are feeling better real soon, Sam.
Bill

Steve,
What I find really interesting is the "cultural" difference between sailing cultures on the various continent..

(My opinion)..
We in Au have been unfortunately been invaded by the heavy plastic under powered under achieving "international" classes..

My father learnt to sail as bailer boy on 6, 8, 10 and 32 foot skiffs.. If you can have a look at the sail areas they used to put up..Then graduated to skippering a home built 6 footer.. (at 13).. My first was a VJ.. 11'6 (just under 3.5 meters) sharpie planing hull.. Sort-of like a pointed bowed hard chined scow, 3'6 wide at the gunwales, and to keep her upright twin planks (the class was designed before trapezes were invented).. 45kg weight limit.. 120? sq feet working sail area with a assymetric kite.. chine to gunwale height 200 mm.. The races started at 1:30 pm.. My local pond has a summer breeze of 22 knots average so many days we started in conditions where foam was blowing off the chop.. On those days I just wore 6 wool jumpers rather than the normal 3.. I was 13 weighed 5 1/2 stone (35kg) I still remember the day we put the kite up and sailed over the Australian 14 skiff champ on a shy reach.. To be honest it was in the days before a wind upper restriction applied.. The hull was out from just behind the centreplate and only 1/3 of the width of the hull.. Scary yes but exhilerating.. I was hooked!!!
A few years ago I unfortunately took my son down to his first sailing experience.. So he went out on an opti... and came back bored.. Now getting him near a boat is difficult as he considers sailing is boring.. When my arm is ok I hope to take him out on the F16 and show him it can make his young heart skip (he is 10).. The first impression is important and takes a lot of good experiences to overcome the first..

My point after the ramble.. Wish I had taken my son out on an higher preformanced boat like an ARC17 (not that I have seen one) rather than let him see an opti..

Weren't the first classes open boxed classes?... A, B, C and D..

Just wondering which new class is "High Tech"?
Nomex honeycomb carbon epoxy was used to build boats in the 80s.. So its now what 20 years old as a technology..