As you all know by now, the rudder specs were chosen to ensure the boat is controllable and the initial intention was to be harsh in the rules so that the first bunch of boats wouldn't get a bad rep before the fleet even started. I pushed for some flexibility and that is why the rule 5.13.6(e) (part ii and iii) provides an out if the 49er class foil become impractical for any reason. The section shape is a big part of the control factor. I cannot take any credit or blame for the section shape of the Aquilo rudders, that honor belongs to the Bethwaite stable. I personally think it might just be possible to make a ruder with the same section shape that has less drag than a 9er rudder, by changing the planform shape. I am concerned however that if the rule is left completely open new rudder cassettes would have to be made and changed every time you use a new blade and blades would not therefore be interchangable at regattas (in case of breakage or for speed and handling testing). Keeping an approved section shape the same as the 49er section and the same chord at the top 12 inches would obviate these concerns. That being said I am for less rules rather than more when it comes to knitpicky rules like rudder shape. Just keep in mind It is not yet certain by any means, which of the two planform choices we have now (that have the same section and approximate area) is faster. Do we want to stop someone making a skinny small rudder with a lot less drag? Probably, we all should be able to guess that with just one win with a rudder like this and a rock star skipper everyone will think they need to have that kind of laminar flow blade to be able to compete. I think this will take the class down the wrong path. Rock star skippers might be able to control a boat with such a blade but the rest of us will just find the boat hard to sail and a lot of peope wont understand why - my real concern, and then they start blaming the class design rather than a stupid desision about the rudder section and area. The other concern is that if we do lock in a shape it should be available to home builders through multiple commercial retailers as a cheap blank. At the moment it is possible to make a rudder, a very good rudder, using a core blank from Aquillo or Wanka for a lot less than the cost of the 49er rudder. I think this is the way to go. I will work to make sure the NYC Skiffs blanks are available if the commercial suppliers fall through on this. I also think it is unfair to the initial builders if they would feel penalised by the class choosing one shape or the other or leaving the rule open. In the event the 49er blade is not chosen the class might be able to supply replacement foam cores to the few boats that already have 49er blades, thus making their loss almost whole again. It is also quite possible I have realised (now that I have much more CNC hot wire experience) to make a foam core that could produce a blade as near as damn it to indistinguishable from the bethwaite section AND planform. ie a 49er board (but it would be MUCH lighter). Roger would certainly be unhappy about stocking these cores for us as he has at certain cost to his business to help the class get to the regatta and then because of a change having to eat his stock. Likewise not fair. To me the rules seem a bit schizophrenic. Almost open CB rule (max width, well how could it be much wider since the case is that wide +1/16 on both sides for packing). and a closed rudder rule. So what do we do about the rudder rule ? Have everyone buy the rudders from Ovington (RIP) or MaKay. That would be an OK but expensive option depending on the health of another skiff fleet. I would suggest keeping the section shape and chord at the top the same as we have been doing add a stipulation that the chord may vary but basic section shape must not change through the longitudinal length of the blade and then have an area and minimum and maximum depth rule, leaving the planform shape up to the builder. This would ensure adequate control characteristics upwind and adequate depth and surface downwind. It is a rather lot of rules though and difficult to control. An alternate sitation is to settle on a "class" foam core design that can be made simply and can be CNC cut simply and cheaply. The object here would be to provide adequate control of both the sailing characteristics and control the cost to make a very cheap rudder available and also to simplifty the rules. My company is branching out into other foam uses and you will all soon be invited to the opening display. http://www.amazingbreasts.co.uk/breast-form-types_50.html Concerning wings on foils. The rules are clear on this matter in my opinion. They are not allowed by rule 5.13.6 (part f). a.. f. No appendages shall be allowed below the waterline on the b.. i. centerboard or a.. ii. rudder Unfortunately we did not protest Mr Dally at the appropriate time. This would have moved Mr Harper into the brown medal position which I believe he deserved. You know this rule taken to its absurdity, you could build a wing-in-ground-effect attachment to the top of the CB or rudder and fly around the course, but if you were able to achieve this why bother with a hull at all.:-) The recent advent of foils on rudders and even centerboards, in my view, is an exciting development. It is very far from clear what this will do to existing open class designs. Really why have a slippery hull at all, a supercavitating wedge might do as well and will begin planing faster. I'm particularly interested in watching how well foils work out on rudders of short WLL boats not unlike the Swift. Mr Dally put the kybosh on allowing that kind of appendage for his design. Time will tell if he was "right as usual". I am certainly not going to second guess him (publicly!). But, I will attempt to fly a boat that looks like a Swift, just for fun at some stage I'm sure, even it its not faster round the pins it would allow me to get in closer to the beach before I have to get out and get wet.. Becoming serious again --- wipes smirk away. Really. 5.13.3 Mast Spar part c. The mast shall have a maximum height of 6.935m (273 inches), which shall be measured from the bottom (or bearing surface) of the heel plug (less the tenon) up the forward face of the mast to the top of the masthead crane. This rule was written in concert with the rule about the white band regulating the hoisted position of the top of the mainsail to keep the mast within reasonable bounds but not to restrict you in the design of the mast head crane, the position of its sheaves etc etc. Especially in case the 49er fitting is inadequate for any reason (apart from being just BUTT UGLY and cheap) since we have no control over another class' fittings, so it seems. My obvious intention, I must now confess, in writing this rule the way it is was to allow one to attach wings of indeterminant width or chord to the mast head crane so that the Swift will be able to fly just above the water like a glider. You will notice the absence of a horizontal appendage or area rule for the mast! Unbeknown to me Mr Dally slipped in rule 5.13.3 part b to a late draft of the rules. Fortunately my lawyer (PC Chris LLP) tells me for my devious plan to clear 5.13.3 part b and qualify as a "fitting" the main halyard sheave can easily be inserted in the trailing edge between the wings. Steve Clark and I are working now on a prototype leveraging the very sucessful vertical Cogito wingmast design for the horizontal Swift solo "wing top mast crane fitting". Look to see it soon on the Vanguard web site. A large Australian fitting manufacturer is interested in this Swift solo part too. Really. You Go Steve. (notice the useless rudder). Why not save 50% of that weight and put it in he middle. Eh!. Bieker agrees with this idea and so do a lot of other designers. Ask my lawyer. While we are on about wings. Those little appendages which cannot be put on the foils, I have got a call into my lawyer about the little wings you see in the videos of the 8teens attached to the hull at the knuckle to stop porpoising or scuba diving. Can any of you get your lawyer to call you back?? whats up with that. I'Il have to say mean things about Loosers -----* again. Ayway, these knuckle dusters might also be available from NYC Skiffs soon. I believe the 8teen knuckle dusters did not become popular because they were not a supercavitating shape with a sharp front edge so that you will not be slowed in case you should run over a competitor. What were they thinking. My lawyer is an expert on this, he is writing a book on it. Here is why it would work. Concerning smaller or Sport sails, one sail or no sails. Go for it! Smaller is faster, just ask Jim Champ or Steve Clark. Jim doesnt seem to need a spinn on his version of a solo skiff either. (he's worried about concrete walls or something). My lawyer tells me Marchaj said something like this too, but Im going to disregard that. Likely anyone who can keep upright and complete the course in an afternoon race in SF bay or the Gorge might just be a winner. I can attest to that. Have a slow day at work once in a while - its good for your bones. Funny ones that is. GR - Rose. http://www.sailinganarchy.com/forums/index.php?showtopic=16036&st=0
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