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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.

Phil S

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  1. A record of over 220 entries for moth worlds at Malcesine in July would indicate the class is in good state.
  2. In AUS the Exocet is almost 50% more expensive than a Mach2. Consequently there is only one Exocet in the country afik.
  3. Not 100% sure but I think the lever locks in to a special fitting on either side and has to be released and moved by hand. But nothing is unchanagble if you do not want to remain in class.
  4. Sounds like the thread has changed from a AS bashing exercise to a big club bashing exercise. Is this where the problem really exists? My small club charges $65 as the AS affiliations fee. Same as my previous 2 clubs over about last 15 years. And its common in dinghy clubs that all sailors are members and AS affilliates.
  5. The Tasar has a rotating mast. One of the crew funtions is to rotate the mast control lever to leeward during tacks and gybes. To single hand the boat you will need to lean forward to the mast to do this. OK if you are big enough have the reach while still keeping most of your weight to windward.
  6. Aust Moth Association pays affilliation fee to AS every year, I know because I was class secretary for 7 years. If the AS web site does not say so then there is a web page problem. We do not pay to state YAs because we deem having state moth associations irrelevant in the modern electronic age. It seems that AS is working to get rid of them too, which should streamline a lot of funtions. They are changing things, not always for the best but I am sure that they are listenning to the critism from the grass roots. The best way for the critics to do something is to stand for office and do the job themselves, what admin or management have you done for the sport Lydia?
  7. Rusto, Great drawings showing the real forces but I think we are talking about much bigger lift/drag ratios, and much finer apparent wind angles. Also at the ratio of boat speed to wind speed of these boats the impact of wind sheer is much reduced so the difference in apparent wind agles between deck and mast top are much less. So if you adjust your drawings with Lift more like 25 times drag (my guess, Stev might have a better number), reduce deck apparent to maybe 10 deg and mast top apparent to 12 degress, I think the picture becomes much more conventional. I think the impact of reflex will become a huge vector slowing the boat.
  8. I have also been critical of the split of funds and attention between Olympic and grass roots sailing, But I have looked at the AS annual reports for a few years and its easy to see why it is so. Most of AS's money comes from Olympic funding not from members, clubs or class associations. So most of their expenditure and effort goes in that direction too. I am not sure our sport needs the Olympics either, but for now thats how it is. What the rest of us get might not seem like much, but we do get a standard set of systems and rules so that we can all sail together on the same water and know where we stand wrt right of way etc. If we had a fragmented collection of associations we would inevitably end up with a fragmented collection of right of way rules, as each new expert thinks they can make a better wheel. A bit like the 5 different football codes we have in Australia. They all started as soccer 250 years ago. We also can go to regattas overseas and sail against other people under the same system. Thats well worth the cost as far as I am concerned. Clubs and classes can get help with rules seminars, regatta paperwork, liason with government waterways autorities, and PR. All available on request. Most of us do not bother asking. The keelboat people also get their measurement and rating system, and their Ocean racing safety standards, without which there would almost certainly be a much more cumbersome compulsary government version. Its not that bad when you look into the details a bit more closely.
  9. Two very good points Steve. Inertia, and anticipation. On small boats we can see the gust approaching by the look of the water. But on big boats most of the gust is way above the water and will not necessarilly show on the surface, in fact at the height of the AC50 rig and in the enclosed sound, the gusts at the top may be completly separate from those on the surface, not just wind sheer but simple turbulance from being downwind of land and buildings. So having something on top of the mast sensing either wind strength and direction, and/or lateral movement would sound like a very good idea. Having it coupled automatically to the trim controls seems like an even better one. Still think this is more likely what we are observing than some elasticity solution.
  10. While I am dubious about the benefits of windward downforce on small cats, due to the relaitve narrow beam and added lift (and associated drag) necessary on the leeward side to balance the downforce created, I do understand that the AC50s are trimmig the windward rudder foil to provide some downforce. But of course having the computer change that angle in response to gusts would be against the rules. Tacking and Gybing is another thing all together where they seem to be changing the AoA of both main foils and rudders during the turns as well as raising and lowering the board. And since all the foil adjustments now seem to be via buttons or touch pad controls, who knows what degree of combination or sequencing is happenning. This barely seems to be "Manual Control", certainly a lot more functionality than a wand does.
  11. Gust response in rigs is a very common falacy. The loads on rigs come form the available righting moment, basic Newtonian Physics, equal and opposite forces. Any variation in wind can not change the righting moment available from boat and crew, at least not in unballasted boats sailed upright like cats and dinghies. In fact if we allow the cat or dinghy to heal even slightly, the righting moments from crew is reduced, the loads on the rig are also reduced, and the mast or what ever other elastometric device you have will relax, in the opposite direction that you want it to. We respond to gusts by feeling the boat start to heal and easing the sails, or as someone said earlier we anticipate the gust approching and adjust the boat to accommodate it by tightenning the cunningham, easing the sail, or luffing, all good boat handling, but the mast can not do this for you. If we think ETNZ has some automated system its more likely to be linked to some accellerometers in the top of the mast, sensing very slight healing movements, and adjusting the flap accordingly. This could potentially feel movements not perceived by the crew and the hydraulics could certainly respond more accurately and more often than someone with a rope or even a keyboard, considering the size of this rig.
  12. Not all foiling boats, but certainly most of the ones which foil well and go fast. For example, the only other concept which has had some real development work was the foil shapes developped before the last Americas Cup, not the flat L shped ones OTUSA acually used to win, but all the rest which were effectively a big Vs under the leeward hull, which were also a rules lead concept, and were a far inferior concept. They rarely foiled upwind with benefit, and rely on the gastly sideslip to relieve excess height, and now most of the smaller cats which have adopted them do not sail much better. The GC32 is about the best and having watched a day's Extreme racing in Sydney I say none of them actually foiling upwind beter than the low riders, and thats with top professional crews in control. It will take a huge effort on the part of another designer or development class group at least equal to what the ACat and Moth people have done to get any other concept up to the same level of development, performance and control. I do not see any manufacturer willing to make that effort, and there are so few other development classes left with sufficient numbers and rules to allow foiling, I see it as most unlikely. Meanwhile Michael's S9 and the Whisper are using the Moth concepts, and the Nacra 17 is using the newer Acat concept. I have not seen a lot of good upwind foiling from any of the others. A lot never make it past prototypes.
  13. ACat Z foils are a very clever refinement of basic old fashioned V foils. They are well refined because the class rules limited other design concepts. Moth T Foils are similarly refined becasue the class rules 15 years ago deemed that twin wing mounted foils contravened class rules. Competely different solutions to similar issues which came about from completely different rule controls. Other than the AC 50s which require lots of hyraulic power and active control, what the ACats and the Moths have refined are way ahead of any other concept wrt balancing ease of operation with performance. Thats why most new foiling designs are incorporating these two concepts. Its not to say that there are not other ideas which could be made to work just as well or better but its unlikely to happen because there is no motovation to go through the tedious refinement process when it might not achieve anything better. As usual one design class creators are just borrowing the trendy stuff from development classes.
  14. But very little good sailing wind days between now and September in Sydney.
  15. From Kevin Ellway, FB Page respecetd UK designer: Ellway Aero-Hydrodynamic Designs added 2 new photos. 14 hrs ยท Had a quick look at some aero hydro for the Acat and Nacra17F for Chris Rashley....so: Q: When does a cat become a monhull? A: When it's got both hulls in the water OR When it's got 4 foils in the water. The A and the upcoming Nacra17F have so called Z foils. These basically form a surface peircing V foil with the middle cut out - just like Brrett Burvill's Moth from 2001 - see pic When there's no leeway, each foil lifts equally so the lateral Centre of Pressure (CoP) is at the centreline of the boat. As leeway increases, the lift on the leeward foil increases and on the windward foil it decreases. This moves the lateral CoP to leeward - see graph. This action is similar to the centre of bouyancy moving to leeward when a boat is heeled. At typical leeway angles, the CofP moves only around 250mm to leeward. This gives the A cat a righting moment of about 2000N.m about the foil CoP. A heeled moth (see previous post) has around 2200N.m of RM. So an A cat has less RM than a moth, but has much more sail area and mast length! An A cat with straight boards would have a RM of around 3200N.m with the windward hull flown. So whilst the Z foils reduce the hydro drag at high speeds, they also greatly reduce the available RM. More on the effects of this planned a future post...