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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.

Hansen Aerosports

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About Hansen Aerosports

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  1. The subject of winglets on sails comes up once in a while but IMHO, the highly specific geometric orientation required for a winglet is impossible given the variable heel, pitching and massively turbulent nature of wind. The only water-borne sailing vehicle without pitching is a windsurfer (with a universal joint) or possibly a hydrofoil craft like a Moth or Hydroptère but the the other variations remain. To drag around a winglet on the top of a sail which is likely only operating part of the time or under very limited conditions seems (to me) like a poor solution.
  2. Baltic: Perhaps they do the same thing in a different way? Just saw this quote in a winglet article attributed to Dave Akiyama, manager of aerodynamics engineering in Boeing product development: "We find that it really doesn't matter what kind of wingtip device you use-they're all like span," he says. "The devil is in the details. Span extensions are the easiest and least risky."
  3. In the mid-late '80's, a Naval Architect student at UC Berkeley did a CFD study on 'closing the gap' with a windsurfing rig and found significant gains in the last few cm's of gap closure with a 6.5sqm sail. Anyone who has windsurfed with performance equipment in marginal conditions has experienced this effect and found it dramatic. In post #47 by SlackWater_SF on 31 December 2005 - 10:33PM in this thread: http://forums.sailinganarchy.com/index.php?showtopic=27993&st=25 I found the following attributed to Tom Speer: Unfortunately, the above applies to una-rigs. My guess is it also applies to jibs but Tom could no doubt confirm and expound on the subject.
  4. Andy: Looking good. Couple questions: Are those camber inducers connecting the battens to the mast? Does the mast rotate? Thanks!
  5. Steve: I like it (not that it matters.) Max 10.6sqm including 1/2 spars - nothing above 6360mm. Simple, fair, plenty of room for innovation within the tradition of the IC. My 2¢...
  6. Phil: I agree on the Moth. Moths are all about apparent wind which builds quickly when flying and they rarely run DDW. Not sure the IC is the same. Even though it is fast, the IC is stuck to the water and changes in wind velocity have a greater effect in overall pressure and direction. My guess is it is a matter of degree which means matching the compliance. Sounds like your rigs weren't optimally matched being too hard in one case and too soft in another. No doubt a tricky problem made worse by a UniRig...
  7. Andy: I'm with you on the control mixing problem. Makes for a challenge in mast stiffness/bend and sail cut. Frustrating until you get it right and then rewarding. The 'springy effect' can be a benefit if the compliance of the rig matches the boat because it gives the sailor a chance to maintain balance. In variable conditions, the velocity squared force generated by building pressure initially overpowers the sailor and by the time he eases the sail and/or hikes out, the pressure is gone or he is capsized. In the real world, most sailors aren't capable of tweaking the strings and hiking out (or the reverse) quickly enough to maximize driving force. A compliant rig smears out and flattens the response automatically with a net gain in time-averaged drive. The problem is matching the compliance and that involves mast bend and sail cut again. Why don't you take the area away from the bottom and add it to the upper leech? I've found I can put a lot more up there than I ever thought at the start. Call it recut #4.5...
  8. Judging from a look at a state-of-the-art El Toro, I'd have to agree. I probably misdirected my 'flame-bait' by mentioning strings instead of (on retrospect) jibs. Adjusting sail shape is even more critical on a UniRig and a more complicated engineering problem if it is unstayed because you get blended rather than independent adjustments. To me, that is the challenge. There will be strings. Let there be strings. Just no jib...
  9. John and Phil: Lots of great info. Couple thoughts / reactions: First, my illustration is based on a Moth sail. The luff round shown is merely a remnant of that work based on an older, softer mast rather than a profile I would consider for an IC (or a Moth at this point.) The illustration was intended to create discussion on the UniRig and the replies are a testament to the level of enthusiasm for the IC. Clearly it is non-unique problem with multiple solutions which is why (to me) it is interesting. The intriguing part is in creating an optimal planform within the rules and ability of the sailor and engineering it to a level of viability. Second, I'll risk getting flamed soundly here but IMO one's level of sailing performance varies inversely with the level of complexity because there is more room to blame poor results on mis-trimmed sails, rigs, blades, etc. That's not to say that C Maas or Steve or the many other highly skilled IC sailors can't make a complex boat perform because clearly they do, only that they would have more time to concentrate and react to the wind and water without so many strings...
  10. I checked the 2009 rule as found here: << http://www.canoeicf.com/site/canoeint/if/d...20-%20DRAFT.pdf. >> In my reading, no portion of the sail can be higher than 6360mm above the bottom of the boat and that is basically it. As such, I'd opt for a shorter unstayed mast (lighter, effectively stiffer, less drag) and moderately peaked head (at 6360mm) placed forward in the boat sufficient to keep the boom out of the way while preserving the square area. The weight saved in all the rigging, control lines and hardware of a sloop rig could be used to beef up the hull torsionally. Should make for a relatively simple, easy-to-sail boat with excellent downwind capability. What that hull might look like is a good project for the many talented folks here...
  11. Gives you 10.4sqm...
  12. I'll raise the clew if you let me make the boom longer. The rest isn't worthy of comment...
  13. Can we sheet it in hard, pull on the strings and then measure? Too busy for another project or boat but will gladly help someone who isn't 'mess' with it a bit...
  14. That is a very good question. From pictures I've seen, the 18' skiffs clearly don't have a problem with peaked heads being taller. Or, maybe they were illegal for class racing? Dunno. A similar sail(s) measured OK at the 2008 Moth Worlds. Later a question at the Moth US Nationals was raised without a clear answer but the fact the sails were approved at the Worlds seemed sufficient. One thing to consider is mast rake and tip bend underway and how it should be figured into the rule. This is particularly important to the Wyliecat 30 and now other unstayed boats in the SF Bay area who are having to deal with PHRF ratings. IMHO, the top of the sail should at least be parallel to the water when loaded. My preference as a sail designer is that it be slightly angled upward and I believe if the overall area is carefully measured and defined, overly peaking the head requires compromises elsewhere as well as engineering problems creating a self-regulating situation. Ultimately, the sail measurement rules will need to look at advances in technology and the idea of limiting headboards to right angles to limit the luff length (which is the original intent) need to be eliminated. Definitely an interesting development...
  15. John: I had a brief look at the class rule WRT area and luff length. Upon further inspection, there could be other problems - not sure. The tube would depend on stayed or unstayed. I like unstayed rigs for their versatility downwind but that might be a structural problem on an IC. Thus, the Moth rig seems like a good place to start or perhaps a hybrid rig that is self-stayed to control/adjust bend but free to rotate... Phil: It may be too long at 5.75m. I arrived at 5.75 after seeing String Theory which was quite low at the deck. The design is very similar to the Moth sail where we learned some interesting things applicable in the future. Leech profile and shape variability are critical and putting a Unirig in an existing IC is problematic but perhaps doable (as you have shown.) My preference would be a unirig-specific or at least less sloop-specific hull such that the mast can be further forward. With that in mind, I think many of the other problems you mention like boom length, vangs and profile become tractable. A bit of a development project but certainly not beyond the capabilities of the people in this thread...