Unlimited C Class Sailboat Racing Rule (UCCSRR?)

Discussion in 'Sailboats' started by Doug Lord, Jan 25, 2010.

  1. Doug Lord
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    Doug Lord Flight Ready

    Open(instead of "Unlimited") C Class Sailboat Racing Rule ?

    This is a basic rule for racing sailboats 25' long with 300 sq' of sail area and a maximum beam of 34'. The rule would not limit participants to any type of sailboat-multihulls and monohulls could compete. Foils would be legal as would be anything not specifically restricted below. The rule idea is inspired by a discussion in the Moth on Foils thread and by the International C Class Catamaran Rule. My interest is that I'm convinced that a C Class catamaran is no longer the fastest type of sailboat POSSIBLE 25' long.
    The beam restriction is high so as not to limit the type of boat that might compete and is based on the L/B ratio of Hydroptere. My gut feeling is that the winning boat to this Rule will be considerably narrower. The course sailing requirement is to make sure that this Unlimited C Class Rule does not evolve to a straight line, speed racing, one tack fits all, boat type.

    How about:
    --LOA 25'
    --Beam 34'(max) or 1.36 times length
    --Weight unrestricted
    --SA 300 sq.ft.
    --crew 2
    --must be raced on a course( specific-like windward leeward or triangle windward leeward)
    --minimum wind speed for a regatta-5 knots
    --maximum wind speed-25 knots
    Not limited to foilers or multihulls-no other restrictions

    Comments and individual ideas of what might be fast could lead to a fun and interesting discussion...
    Last edited: Jan 29, 2010
  2. Gary Baigent
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    Gary Baigent Senior Member

    Thought C Class was 25 feet x 14, not 24, long, Doug (or is the rudder not counted, that's a crappy joke by the way). An open C Class would reinvigorate C Class with many innovative designs and become a hotbed of ideas - and produce maybe some cheaper, if not a lot faster alternatives. But do they want that?
  3. Doug Lord
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    Doug Lord Flight Ready

    Unlimited C Class

    You're right-I had brain fade-sorry and corrected. The Unlimited C Class would change -basically-only the beam restriction so that foiler types with an L/B ratio like Hydroptere could compete. It is a rule that should reflect what is known now about fast sailboats. The Race of the Century would be the winner of this Class' World Championship versus the Fastest C Class Catamaran in the world.
    What kind of boat would you design for this Class ,Gary?
    They don't have to want it-this class takes nothing away frorm C Class cats -it is simply an unlimited C Class.
    Suggested rule interpretation: LOA means TOTAL LENGTH . I wouldn't want to see these boats sprout gantries(Moth,I-14 and others) or stern tubes(like Rocker)
    Pictures show Moth rudder gantry(11' Moth becomes 13' Moth) and C Class Rocker stern tube extentions-33"(25' C Class Cat becomes 27.75') :

    Attached Files:

  4. Doug Lord
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    Doug Lord Flight Ready

    C Class Cat vs C Class Monofoiler/ Old Rule

    This is my idea of a boat that could be very fast under the Unlimited Class Rule and under the C Class Cat rule. Numbers done over a year ago-the new rules boat could but not necessarily would revise the rig on the monofoiler to potentially the same as a C Class cat with a commensurate increase in beam(and weight) under the Unlimited Class rule:
    C Class Cat
    A. I found numbers for Invictus: 170kg(374lb) all up ;75kg(165lb) wing, 95kg(210lb) hull,cross beams, foils.
    For the purposes of this comparison I reduced Invictus numbers to: 163.63kg(360lb)* all up,72.18kg(158.8 lb.) wing,91.44kg(201lb)hull,cross,foils.
    Note: on both boats crew CG figured at 1m(3.28') from side of boat(or racks):
    Crew weight: 320lb(145.45kg)
    Measured with boat just flying a hull:
    --1) CB lee hull to boat CG: 6.5'(1.98m)(assume 1'(.3m) hull beam)=RA; 6.5 X 201=1306.5ft. lb/ 1.98 X 91.44=181.1kg/m
    --2) CB lee hull to crew CG:6.5'(1.98m)+7'(2.13m)+3.28'(1m)=RA; 16.78' X 320lb=5369.6ft.lb / 5.11m X 145.45kg=743.3kg/m
    --3) CB lee hull to wing CG: 5.635'(1.71m)=RA; 5.635 X 158.8= 894.83 ft.Lb. /1.72m X 72.18kg=124.2kg/m
    --4)C Class Cat Total RM:= 7570ft.lb / 1049 kg/m

    C.----- Total weight: 320+360=680lb /145.45 kg+163.63=309.08kg(UPDATE: 1/26/10-according to Steve Killing Alpha-last Little America's Cup winner weighed 750lb/340.9kg all up with crew. *Hull,foils and rig for Alpha=360lb/163.63kg)
    D. CE at 19'(5.79m)
    . Bethwaites Ratio: SCP/Total Weight
    1)SCP= RM/ CE-CLR
    a.-SCP=7570/19=398.42 // 1049/5.79=181.17
    2)SCP/Total weight=398.42/ 680=58.6%// 181.17/309.08=58.6%
    3) SCP/Total/WEIGHT(STEVE)=61.7%/color]

    F. W/SA=2.26
    W/SA(Steve)= 2.53
    Note: SA/ sq.ft. wetted surface flying a hull,one board,one rudder=8.42/1
    ROCKER---Note: SA/sq.ft. wetted surface on foils(including immersed portions of daggerboard and rudder)= 23.18/1
    W/SA(ROCKER)= 2.55

    C Class Monofoiler
    Note: crew =320lb(145.45kg)
    A. --- Righting Moment
    1) Veal Heel adds 1.5'(.457m) to righting arm
    2) crew-1.5'(.457m)+7'(2.13m)+3.28'(1m)=RA; 11.78'X 320=3769.6 ft.lb // 3.587m X 145.45=521.73kg/m
    3) hull +foils- 120lb X 1.5'=180ft.lb // 54.55kg X .457m=24.93kg/m
    4) wing 140lb X 4.5= 630 ft.lb // 63.63kg X 1.37=87.18kg/m
    5)C Class Monofoiler Total RM: 4579ft.lb// 633.84kg/m
    B. Total weight=320+260=580lb(263.64kg)
    C. CE 13' (3.96m)
    D. Bethwaites Ratio-SCP/Total Weight
    a. 4579/13=352.2 // 633.84/3.96=160.06
    2)SCP/Total Weight: 352.2/580=60.7%// 160.06/263.64=60.7%

    Note: SA/sq.ft. wetted surface on foils(including immersed portions of daggerboard and rudder)= 23.47/1

    NOTE: if the hull weight goes up 50lb(22.7kg) then the ratio changes to 56.8%
    To see the potential of a C Class monofoiler you have to look no further than the Moth vs an A Class cat:
    Moth vs A Class cat-----
    1)Moth RM=900ft.lb. .
    2)A Class RM=2325ft. lb.;
    This might help you to see that the sq.ft.SA to sq.ft. wetted surface is an accurate comparator of potential speed when comparing a foiler(on foils) to a "normal" multihull'. This is sort of like comparing test results from two large models and finding them in agreement with design predictions:
    Moth: 17.8sq.feet SA per sq.ft. wetted surface ( including submersed portion of daggerboard and rudder when on foils)
    A Class cat: 7.8 sq.ft.SA per sq.ft wetted surface(flying a hull, one board, one rudder)
    This is important because ,according to Rohan Veal,Bora Gulari -and others-the Moth is faster than an A Class cat in conditions over 10 knots!
    S0, it looks pretty good for a C Class Monofoiler vs a C Class Cat especially considering the foiler is lighter and has the same sail area with far less drag(on foils).
    It is worth noting that the aspect ratio of the A Class cat is substantially higher than that of a Moth....
    Oh, the wetted surface for the two boats(C Class Cat & C Class monofoiler) is within 2% when the foiler is off the foils. And a retractable foil system might be possible. Worst case for the foiler would be marginal foiling conditions. In wind over about 5 knots the foiler is flying.....

    And if all that doesn't make you think-then this should knock your socks off:
    1-Top Speed for C-Class Catamaran: 23 knots(26.45mph) source: Steve Killing and Team Alpha
    2-Top Speed for the Moth monohull foiler(monofoiler): 30.31 knots(34.86mph) source: Bora Gulari

    This is no guarantee of anything-just very interesting numbers.
    Note: this rough comparison was done to the "old" C Class rules with beam limited to 14'. The new Unlimited Rule would allow more beam but it is NOT a given that more beam would make the monofoiler faster. Small "Power Foils" might make more sense in stronger winds(for a very small-2% approx. weight gain)....
    Last edited: Jan 30, 2010
  5. bistros

    bistros Previous Member

    Oranges versus Apples again


    I have no problem with new ideas. I like new ideas to be labeled as such, though.

    By calling your new idea a "C Class", you are attempting to piggyback your idea onto an existing class, with a long and valued history. I seem to remember Steve Clark reminding you in the past that once you go outside the box, it isn't a C Class anymore. Your response was that the rules should change to fit your idea.

    For the love of God, please don't attempt to bring legitimacy and credibility to a new idea by attempting to hijack the legitimacy and credibility of a design rule that has already stood the test of time.

    If your idea has value (and I think it may) let it earn it's own place in the world without devaluing something else.

    People like Steve Clark and Fred Eaton are very happily innovating and advancing the existing C Class while respecting the rules. They've invested more into their designs than almost anyone here has in a comparable single class design. Fredo's last C Class venture was around $1,000,000 invested for Alpha and Rocker (also acquiring Patient Lady as a control).

    Steve's new design is just now reaching assembly and major component refinement.

    Be proud of your idea and come up with your own name, and your own marketing campaign.

  6. Doug Lord
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    Doug Lord Flight Ready

    Unlimited C Class

    I think that the Unlimited C Class defines this concept succinctly and doesn't-in any way-interfere with the C Class Catamaran rule. My original idea proposed to Steve was to change the C Class Catamaran rule-that is NOT the intention with the Unlimited C Class rule.
    A,B, C and D classes have long been specified by sail area.
    World Speed Sailing Records can be established in the following classes (that are not specified as multihulls or monohulls!) I think Unlimited C Class is fine....Go to the site below and look at all the C Class winners-most of which are foilers.

    10 sq m (up to and including 10 sq m)
    A Class (from 10 sq m up to and including 150 sq ft (13.93 sq m))
    B Class (from 150 sq ft up to and including 235 sq ft (21.84 sq m))
    C Class (from 235 sq ft up to and including 300 sq ft (27.88 sq m))
    D Class (over 300 sq ft)
  7. bistros

    bistros Previous Member

    Apples are NOT non-citrus northern oranges

    Sure Doug, you can dance around the issue and avoid my point. Adding the Teflon-impregnated weaselword "Unlimited" does avoid a direct slap in the face of the folks already in the game, but it doesn't avoid the slimy issue at all.

    Since it is sailing, most people expect polite restraint and honorable behavior.

    It appears you just don't understand why people could be upset by your labels.

    You are setting yourself up to be the Ernesto Bertarelli of Little America's Cup. Look how much good Alinghi's done for the America's Cup (and all the lawyers)!

  8. RHough
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    RHough Retro Dude

    The rule is too restrictive to have the label "unlimited"

    There are three or four things you can use to have a single limiting factor:
    Sailing Weight
    Sail Area
    Number of Crew

    As soon you limit more than one of these, you have a type forming rule.

    I'm not sure how different values of these three factors would effect the optimum design. At lower values the costs are lower but crew weight becomes a larger percentage of the total. As sailed boats like Moths and C-Class Cats are insanely heavy compared to what can be done with larger boats. Compare "as sailed" D/L of a Moth or C-Cat to the big Ocean Tris, the big tris are under D/L = 15

    For an next to unlimited development class, try to wrap your head around a "string" rule rather than a "box" rule. :)

    Pick a number ... say 100
    Length + Beam + Total Draft (top of rig to bottom of foil(s)) = 100ft

    50 feet from top to bottom leaves any combination of length and beam that total 50 feet. For your very limited C-Class rule at 25+32 = 57 leaving 43 for total draft.

    We already have what could be a totally unlimited rule ... Rule 52.

    As long as humans can sail it using only manual power it can race. The 90 foot LWL limit for the America's Cup is larger than what can be sailed efficiently by humans. Human power is a natural limit and no other rules are required. Unfortunately this simple limit ends up with boats that are too big and far too expensive to see any real development of Rule 52 boats.

    You could just have Unlimited 1, 2, 3, 4 with the number being the number of Crew.

    Just a thought or two. :)

  9. Paul B

    Paul B Previous Member

    The way IYRU set up the C class (and A, B, and D) is as "unlimited" as you could want.

    Simply maximum 300 sq. ft of sail (including spars) = The Rule Book.

    There, the "Unlimited" C Class. Funny, it already exists without any help from people with their own agendas of fitting artificial limits to a class so their pre-disposed idea might turn out to be the best solution.

    In fact no one, especially not the guy who started this (yes, yet another) useless thread, is going to spend the US$MM it would take to dominate the class. As soon as someone does that everyone else goes home (assuming incorrectly there would be anyone else to begin with).

    Might as well start a thread about how neato it would be to have a flying car, and how you just might get insert starlet's name here to go out with you if you had that flying car.
  10. RHough
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    RHough Retro Dude

    Is 300 sq ft still the only rule? If so ... this is truly a useless thread. If the C class has adopted more rules over the years that limit flights of 300 sq ft fancy, then the class is no longer "unlimited" :)

    Agree 100% that most rules proposed by designers are intended to evolve into some project that is already in the works. That should give the rule maker's first gen boats an advantage over the others and turn the new class into a cash cow.

    If you can build a 300 sq ft mono bifoiler and race C Class ... then someone should try it.
  11. Doug Lord
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    Doug Lord Flight Ready

    Open C Class Rule(?)

    The point of the proposed rule(post #1) is to:
    1) maintain the same sail area and length restrictions that are part of the current C Class Catamaran rule-primarily as a cost containment measure but also to facillitate existing C Class cats' participation if they choose to.
    2) Eliminate or greatly increase the beam restriction in light of modern multihull design-square or over square designs are common. The fastest sailboat in the world has a beam 1.36 times its length which seems like a good limit.
    3) Eliminate the "type" restriction of the C Class catamaran rule so that monohulls, proas ,trimarans could all compete within a basic framework.
    So instead of "unlimited" how about: "Open C Class Rule"? The rule would also include a requirement for course racing and a minimum and maximum windspeed. The idea is to develop a rule that allows modern multihull and monohull designs to compete together within a slightly limited framework that includes course racing.
  12. RHough
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    RHough Retro Dude

    Nope, the intent of the rule is to create a class that will allow boats to compete with an established class that banned them for good reason.

    I offered suggestions for open rules that are not type forming. You just want to see the boats you like sailing in a class where they are not wanted.

    Try this. Use ONE idea.
    2 crew
    24 feet length
    300 sq ft
    or a "string rule" that is based on the current C class boats.

    Design and build a boat to that Open Rule and go sail it against a C Class Cat.

    If you can show that given equal restraints as listed above, there are faster options, your idea might get some traction and not be seen as just trying to get someone else to build something to see if would work.

    IMO such an Open Class would have merit, your type forming class does not.

    You asked ... that's my opinion.

  13. Paul B

    Paul B Previous Member

    The IYRU never banned any type of boat from sailing as a C class. Boards, monohulls, cats, tris, even quadhulls have sailed as C class boats.

    Of course the more famous subset of the C Class is the International Catamaran Challenge Trophy (nee Little America's Cup) that only allows catamarans with C Class rigs and a few other limited dimensions. Due to lack of interest for almost 10 years ('96 to '06) the trophy went to the F18 class. The C Class Cats then started a new trophy (I4C) based on the old ICCT.

    This is one trophy for specials within the broader C Class. It is not THE C Class.

    By definition any boat that flies a maximum of 300 sq. ft. of sail (including spars) is a C Class. Even a J24 falls into the C Class requirements (excluding spinnaker).
  14. Steve Clark
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    Steve Clark Charged Particle

    If I might have a word.

    The thing I have been sailing all these years is a C Class Catamaran. If one assumes that 300 ft^2= "C Class," there is no reason why there couldn't be any number of "C Classes" There could be C Class Trimarans, Foilers, Monohulls or whatever. These might have their own set of type forming limits depending entirely on what made sense to those involved.
    I don't perceive a huge groundswell for restricted sail area development classes. If one looks at the current trend in design, it seems that unlimited sail area is a more popular concept.
    IF a number of these boats existed, it might be interesting to see how they compared.
    When other stuff exists, we can talk about it.
    I don't think it makes sense to speculate further.
    1 person likes this.

  15. Doug Lord
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    Doug Lord Flight Ready

    Open C Class

    Steve, just for the fun of it, what kind of boat do you think could be designed
    under this "open " rule that might beat a C Class cat? In other words, with all your high performance experience, what direction do you think design would move given virtually unlimited beam(1.36 L) and no "type" restriction? Not really speculation-just design imagineering...
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