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    • UnderDawg

      A Few Simple Rules   05/22/2017

      Sailing Anarchy is a very lightly moderated site. This is by design, to afford a more free atmosphere for discussion. There are plenty of sailing forums you can go to where swearing isn't allowed, confrontation is squelched and, and you can have a moderator finger-wag at you for your attitude. SA tries to avoid that and allow for more adult behavior without moderators editing your posts and whacking knuckles with rulers. We don't have a long list of published "thou shalt nots" either, and this is by design. Too many absolute rules paints us into too many corners. So check the Terms of Service - there IS language there about certain types of behavior that is not permitted. We interpret that lightly and permit a lot of latitude, but we DO reserve the right to take action when something is too extreme to tolerate (too racist, graphic, violent, misogynistic, etc.). Yes, that is subjective, but it allows us discretion. Avoiding a laundry list of rules allows for freedom; don't abuse it. However there ARE a few basic rules that will earn you a suspension, and apparently a brief refresher is in order. 1) Allegations of pedophilia - there is no tolerance for this. So if you make allegations, jokes, innuendo or suggestions about child molestation, child pornography, abuse or inappropriate behavior with minors etc. about someone on this board you will get a time out. This is pretty much automatic; this behavior can have real world effect and is not acceptable. Obviously the subject is not banned when discussion of it is apropos, e.g. talking about an item in the news for instance. But allegations or references directed at or about another poster is verboten. 2) Outing people - providing real world identifiable information about users on the forums who prefer to remain anonymous. Yes, some of us post with our real names - not a problem to use them. However many do NOT, and if you find out someone's name keep it to yourself, first or last. This also goes for other identifying information too - employer information etc. You don't need too many pieces of data to figure out who someone really is these days. Depending on severity you might get anything from a scolding to a suspension - so don't do it. I know it can be confusing sometimes for newcomers, as SA has been around almost twenty years and there are some people that throw their real names around and their current Display Name may not match the name they have out in the public. But if in doubt, you don't want to accidentally out some one so use caution, even if it's a personal friend of yours in real life. 3) Posting While Suspended - If you've earned a timeout (these are fairly rare and hard to get), please observe the suspension. If you create a new account (a "Sock Puppet") and return to the forums to post with it before your suspension is up you WILL get more time added to your original suspension and lose your Socks. This behavior may result a permanent ban, since it shows you have zero respect for the few rules we have and the moderating team that is tasked with supporting them. Check the Terms of Service you agreed to; they apply to the individual agreeing, not the account you created, so don't try to Sea Lawyer us if you get caught. Just don't do it. Those are the three that will almost certainly get you into some trouble. IF YOU SEE SOMEONE DO ONE OF THESE THINGS, please do the following: Refrain from quoting the offending text, it makes the thread cleanup a pain in the rear Press the Report button; it is by far the best way to notify Admins as we will get e-mails. Calling out for Admins in the middle of threads, sending us PM's, etc. - there is no guarantee we will get those in a timely fashion. There are multiple Moderators in multiple time zones around the world, and anyone one of us can handle the Report and all of us will be notified about it. But if you PM one Mod directly and he's off line, the problem will get dealt with much more slowly. Other behaviors that you might want to think twice before doing include: Intentionally disrupting threads and discussions repeatedly. Off topic/content free trolling in threads to disrupt dialog Stalking users around the forums with the intent to disrupt content and discussion Repeated posting of overly graphic or scatological porn content. There are plenty web sites for you to get your freak on, don't do it here. And a brief note to Newbies... No, we will not ban people or censor them for dropping F-bombs on you, using foul language, etc. so please don't report it when one of our members gives you a greeting you may find shocking. We do our best not to censor content here and playing swearword police is not in our job descriptions. Sailing Anarchy is more like a bar than a classroom, so handle it like you would meeting someone a little coarse - don't look for the teacher. Thanks.

MountainCat

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About MountainCat

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    A-cats, Windsurfing, Skiing and Trail Running.
  1. Lars Guck won the last three races on a modified Nacra A3 with custom foils built by himself beating Strubles boat with DNA Foils. It would be great to get details and photos of Lar's foils and rig set up. A US manufacturer of competitive A -class foils will be a boon to sailors like myself looking to convert an older boat. Anyone?
  2. No evidence at all. I didn't see any pictures or hear of anybody lifting their rudders up in light weather because they had the cassettes. It is problematic for a number of reasons. First, iot doesn't take much more wind for you to need the rudders fully down, so you need to be 100% confident that you are not going to see a change in wind strength. In reality, if races are sailed in the class minimum wind, you would not choose to lift your rudders. Doing it during the race would give up a fair amount of ground. I really don't see it as an issue. I am interested in why you prefer L foils. I am sure Exploder will sell you them if you want swing ones, but I am not sure why you would buy the Exploder L's when their T's are proven to be faster. It is probably true that the L's are slightly easier to foil with in marginal stuff, but their advantage is in such a narrow wind band that it really isn't worth going with it. I have just spoken to the last person I wanted to check in with before writing anything, so will now try to write a round up from the worlds based on what 4 different sailors have said to me, although the picture is slightly blurred because they don't 100% agree! L foils can be molded in one piece so in theory they should be cheaper with less assembly and finishing labor involved. L foils are easier to protect with a continuous padded sock. In theory, L foils should be faster because they have 2X the aspect ratio having 1 foil tip rather than 2. Of course speed on the course trumps all. I have also heard mentioned that L's are more prone to breakage because of greater asymmetric loading.
  3. I have been trying to tell people for ages that converted boats can be just as fast as purpose built boats. Stevie Brewin did all his training for the worlds on a converted DNA. In addition, his converted Nikita was a weapon. He has won events in converted boats. Thanks Simon for your thorough update. I actually prefer L swing rudders. They seem to be rare. Are there any available commercially? My concern is that in light winds the cassette rudders can reduce wetted surface and may have substantial advantage over swing rudders. Has there been any evidence for that?
  4. What about Mast Flex? Hundreds of A-cat owners (including me) have non-foiling a-cats we are are debating whether to upgrade or eventually replace. The foiling Nikita gives us hope that curved board DNAs, Flyers, Nacras and other carbon A-cats can be successfully upgraded to foiling. It is hard to know the optimal upgrade path. It would be great to hear about the relative success of the latest tech development from the Worlds such as: 1. L cassette rudders versus T swing rudders in light winds? 2. Effectiveness of the short straight traveler in light winds? 3. Thoughts on optimal board and rudder rake? 4. Optimal mast flex with the flatter, tramp seal foiling sails; Bendy masts or a bit stiffer now? Anyone?
  5. MISSED OPPORTUNITY Spectating at the Americas Cup Park was terrible (I was there) with only the bottom third of the course visible and standing crowds at the pier edge with most unable to see clearly because of people standing in front of them.. Why wasn't the 9,000 seat amphitheater positioned to provide good viewing of the race course as well as serving as the concert venue? Oh yes, that would have required smart planning and foresight, apparently both in short supply.
  6. Thank you Dan and the rest of you all for your thoughtful replies on my proposal for a Planing Optimized IC (PO-IC). I don't expect to convince anyone here that it's a better design. I am hoping my boat will be positive proof. I merely want to vet the idea to confirm it's not totally wacky and a waste of time. It seems that at least a few of you think the PO-IC might be fast in specific conditions. Maybe 14 - 20 knots and flat water? In high winds, I think the biggest risk is too much pounding in waves, but I won't know for sure until I try it. The early posts remark how noisy Steve Clark's Josie design was in the waves. For light winds I will make a big effort to optimize the shape for minimum wetted surface and wave making when heeled at 30 degrees. When heeled at 30 degrees, I cannot avoid the hull shape from being quite asymmetric. I am not sure how to think about that. One advantage of the PO-IC is that it will be considerably more stable than other designs with the wide flat sections aft. Not much help though, if it's always too slow. I admit that the semi-displacement narrow designs including and similar to the Chris Maas designs may be very close to optimum for the now existing IC rule; but I am willing to spend some time and effort to see if my ideas have any merit. Already your posts and feedback have me considering several improvements to further optimize the PO-IC design. I think it may be especially important to avoid any bottom curve in the stern flat sections to keep the downward suction force to a minimum. (No sucky time.) I am thinking that I will concentrate all of the bottom curve in the forward 40% of the boat where the cross-sections are curved. In my board sailing, I have compared side by side rockered tail sailboards to straight tail sailboards. The difference is a night and day; the straight tails are very noticeably more low drag and faster while the rockered tail boards are slow to plane and draggy but very easy to turn. I don't think my PO-IC will be "horrifically" slow in light winds if it is properly designed and sailed heeled up on its chine. I think it will be just a small bit slower than other IC's. I am pretty confident my PO-IC will be quite a bit faster than either the foiling moth or the formula boards in 3 to 7 knots due to its longer water line length. FWIW both of these classes with worse light air performance (assumed) than my PO-IC have chosen to sacrifice their light air performance and concentrate exclusively on medium and heavy wind performance. If I am not mistaken, most remarkably, the foiling moths were first dominant in regattas with mixed boat styles and variable wind speeds. Maybe someone with more experience can comment? I don't consider the build risky. If the PO-IC doesn't work satisfactorily, I will just cut off the bottom stern half and fabricate a new one with some curve in the bottom cross-sections. The alternative would be to add sail area and triple the plank length and try to set speed records! ;-) I will try to post my design in the coming weeks. As of now, the design is pretty rough and only in 2D. This is a great discussion by everyone here. I am learning a lot about hull design. Thank you all. M-Cat
  7. I am not convinced that an IC hull optimized for early planning would not be fast in most conditions. Yellow Pages/Macquarie Innovation and the Vestas Sailrocket both use planing hull shapes in their hull pods to achieve speeds over 47 knots; so the high speed potential of planing hulls is certainly there. Formula sailboards are similar in size, weight, sail area and typical expected sailing conditions to new rules ICs. Comparing the sail to weight ratio of a Formula Experience sailboard to a new rules IC with a 75kg helm we get: FE Big Rig: 11.0 m2/ 75 + 15 kg = 0.122 m2/kg FE Small Rig: 7.8 m2/ 75 + 15 kg = 0.087 m2/kg New Rules IC: 10.0 m2/ 75 + 50 kg = 0.080 m2/kg So the IC appears to be in a similar power to weight range at least in high winds when the FE uses the small rig. Another way to look at this data is to observe that the IC is underpowered in light winds and could use a larger light wind sail plan! Of course the comparison above is apples to oranges. The Formula board is likely more efficient than an IC in the following number of ways: Canted rig Sleeved mast Bottom of sail closed off with an effective end plate Single foil with size and shape optimized for wind speed The majority of weight is isolated from hull wave shock by the sailors legs My questions are as follows: Are these Formula board advantages so great that their optimized hull shape has no application to a new rules IC design? Are there no hull shape ideas that can adopted from the optimized Formula board design to IC's? The fastest Formula boards have settled on an optimized design with a width of 1000 mm, a dead flat tail section out to hard chines, little to no tail rocker and sometimes with a cutaway step within 300 mm of the tail. IC's have one advantage over Formula boards in that they have no concern for rocker and rail shapes that facilitate sailor initiated turns by leaning. Formula board bottom shape shown above. Formula boards seem to have a very narrow semi-planing wind range. They go from displacement mode at about 6 knots wind speed to what seems to be a fully planing mode at about 9 knots wind speed. The velocity change through the transition is rather amazing as the board speed can go from about 4k up to as high as 16k with a wind increase from 6k to 9k. The speed transition to "planing speeds" is often assisted by the sailor pumping the sail. The large change in board speed over a relatively small change in wind speed seems to me to be evidence that the board is making a clear "break from one regime to another." Has any one tried building an IC with a Formula sailboard type stern? That is: dead flat cross-sections out to the hard chine and a straight keel at the stern (no rocker). Of course such a design would have a much greater wetted surface and would be slow in low winds just as Formula boards are. Low wind speeds <7k might be accommodated in such an IC design by heeling the IC 30 degrees to leeward in light winds to reduce wetted surface in a similar fashion to how inland scows are sailed. I don't see any reason why an IC optimized for early planing can't fully plane in 9k of wind with the right (bigger) light air rig. My IC designs to date for my upcoming build all feature dead flat cross-sections out to hard chines at the stern, stern widths between 900 and 1000 mm and no rocker or keel curvature in the aft half. What do you think are the chances that such a design might be fast? M-Cat
  8. I found this thread by searching on "planing hull shape sailing anarchy," I was hoping to find information for use in my planned design and build of an A-class cat. As I read through the posts from the beginning my thoughts evolved as follows: 1. I might find something in this thread useful to my A-class cat design. 2. IC's are very odd boats. 3. I am disappointed not to find more discussion about planing hulls. 4. I am amazed by how much the photos of pointy DC's resemble both skeeter ice boats and miniature speed record proas based on the full sized Crossbow I and Slingshot. 5. These DC's are an interesting class. 6. These DC sailors are an amazingly helpful and friendly bunch. (unusual on SA) 7. DC's are amazingly fast for their size and sail area. 8. DC's are much simpler to build than A-class cats. 9. I might build a DC as practice for my upcoming A-class build. 10. This thread has lots of great technical information. 11. I start to design a DC. 12. I print my design and build a paper model at 1/16th scale. 13. I design 2 more DC's and build 2 more paper models. 14. I am definitely going to build a DC. 15. I might try to charter an IC to race this summer in at least one regatta. 16. I'm spending way too much time reading DC posts and researching IC's. 17. DC's are easier to store than A-class cats. 18. DC's are easier to transport than A-class cats. 19. DC's are cheaper to build than A-class cats. 20. I've become addicted to reading DC posts. 21. I don't think I'll build an A-class cat. By now you can probably tell that I've had way too much IC Kool-Aid. By the way, thank you all for your great posts! Oh yes, back to reality. Where can I find the US IC regatta schedule for 2012 and how can I go about chartering a boat for one of them? Just one more IC nut case, Teejay