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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.

edt

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About edt

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    mi
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    kites
  1. i cant wait until kite designers make changes. There hasn't been any change in kite design since the Legaignoux brothers invented the kite bridle in 2004 or so. Kite manufacturers have needed a kick in the nuggets for a while now to get them out of their comfort zone. I know I said, why would kite manufacturers build this, but I realized they have needed this sort of challenge for a long time, they just never knew it. Thanks sailrocket. We needed that.
  2. that's not the angle of the kite lines it's the angle of the pull from the kite which is also dependent on angle of attack. This particular diagram is when the rider is going 50 knots, so for current kites there is almost no extra speed it can take. For the more advanced kite you can see that you can add another 20 or 30 knots before apparant wind shifts so that the kite pull is perpendicular to the direction of travel. The diagram is just a snapshot at a particular speed
  3. That's because the best kiters in the world are in france rite now waiting for the mistral rob douglas alex caizergues etc. Luderitz is more about looking at some nice national records. Rob just did a 53 in an easy practice run at salins du midi, in less than ideal wind. don't expect to hear about this from the ludertiz site they are competitors for the best speed kiting location. "As regards the outright World Speed Sailing record, recently set by Sailrocket, that’ll take time but we’ll get there." -- morgan douglas rob's little bro
  4. Actually it is very very easy to improve the L/D ratio of kites. Right now kites run an L/D ratio of somewhere around 3 or 4 to 1 tho of course L/D is not just a number but a function of wind speed. Personally I like to ride Fuels, which has an even worse L/D ratio. The advantage of low L/D's in wakestyle is that when you load to pop out of the water, the kite has further to travel to the edge of the window giving you better pop and better slack for your handle pass. Also when the kite stays deeper in the wind window it is much less likely to hindenberg and fall out of the sky. Now it's true a better L/D ratio helps you go upwind better and gives you a better top speed, but it doesn't really matter, you go upwind so you can do a trick downwind it doesn't matter, what you want is good handling. Kites with high L/D also are really awful doing megaloops, they don't give you a big yank downwind. Anyway, there are a bunch of other reasons, but even with racing kites like the cab kites that tend to win all the races, the L/D ratio at 65 knots is not that important because when we go kite racing, it's always about 10 knots. When the wind picks up to 20 knots, racing is called off for that day and we switch to freestyle. There is simply a tremendous amount of improvement that could be done to the kites. Will it be done? Do we really want to go 65 knots in a kite? I dunno. Our boards are not where the improvement needs to be it's in the kites. We could easily get up to 10 or 15 to 1 L/D ratio's but you couldn't use that kite for freestyling, only for racing, and it wouldn't help normal racing, only high speed racing.
  5. The entire board is a ventilating fin, the actual fin on a speed board is there only for stabilization. While a formula kite racing board will start out flat and then foil up off the fins a speed board uses the edge of the board to foil. I'm convinced the boards are very well designed. The best kind of R&D has gone into them, the trial and error at high speed kind. There has been zero R&D for kite design at high speed. I'm not sure kiters actually need to get to 65 knots. So dangerous, I would hate to lose someone over this.
  6. modern kites have tons of drag that's why they can't get more efficient vectors, they fall backwards into the wind window a typical leading edge is 6 inches to a foot in diameter
  7. It's all related to the polar of your sailing craft, draft and lift. You might have noticed as you sail faster and faster the angle of apparent wind moves upwind into your direction of travel. A more efficient sail lets you sail closer to the wind and go faster. Right now kiters are bound by the inefficient kites at 1.2x wind speed. Now of course you can build a stronger boat and just make the sail bigger, and force the kiter to pull harder, but what good does it to go build everything bigger for incremental improvements, when you can almost double the efficiency with a better kite.
  8. rite now the speed kiters are pulling 50-100 pounds and accelerating at less than half a G. We aren't even close to human limits. The kites however are like giant sky anchors. Kite lines snap at between 600 and 800 pounds and you shouldn't put more than 300 pounds on them.
  9. Just think about how the polar diagram works for all sailing craft and you'll see why improving the kite efficiency is so important. There is a loss of control going from a higher aspect to a lower aspect foil on kites. I think our boards are about as close to that as we want to take it. Kiters are constantly flying their kites and adjusting their center of gravity in response to the wind just the same as the sailrocket is constantly adjusting his sail rudder, it's just that it's more easy to see on a kite. The sailrocket has potental to get up to 80 or 90 knots. Right now I think we can catch them with mere design changes in the kites.
  10. From a standing position Rob can pull about 1,000 with his legs through the 500 meter course, if that force is directed towards the finish, he will be able to withstand about 3 and a half G's worth of acceleration more force than the space shuttle launching. The human is not the weak link here. The problem is that the kite at 50 knots is all drag, so we just end up plowing up a huge rooster tail and not getting any more speed. With a better kite (a wing), I think this record is in reach. But, I don't think Cabrinha is interested in building one because there's no money in it. We are stuck at something like 1.2x wind speed. Our lite wind kites and race boards by contrast can get 2x or more wind speed in 10 knots. That's where the R&D is.
  11. I think our boards are fine, we have done a lot of experimenting with them but our kites are like the other guy said off the rack cabrinha switchblade. The problem with our current kites is that we have all this force pressing directly downwind. With a more efficient kite, that pulls upwind, you don't have to be nearly as strong and you can go much faster. Kiters might just give up on it, the kite buggies after all don't try to chase the greenbird, which rocked out a 126 mph run. The greenbird looks much like the sailrocket except the wing is on the main body not the leeward pod. Kitebuggies are up to 84mph. The problem with a 65knot record is that it's far away and tantalizingly close. I think with a bit of kite R&D we can break it. the Sailrocket looks like she has some more speed in her with more tweaks. She'll need another huge run to put it completely out of reach like the greenbird did on land.
  12. That's what I think. We are limited to 2012 technology and can only build so big.
  13. Exactly. so when you double a three 3 dimensional object in size its mass increases by a factor of 8. But the strength of all the parts only increases by a factor of 4 because the strength of an object is proportional not to the mass, but to the cross sectional area of all of the parts. So you double the diameter of your amsteel blue line and its four times stronger. But the sail rocket itself weighs 8 times more. so when ever you double the size of everything in a 3-d object it is half as strong proportionally so unless you switch to more exotic construction techniques something is gonna break. This principle applies to hang gliders, airplanes, submarines, cats and elephants, and also the sailrocket. I am pretty sure that the sailrocket right now is almost perfectly sized.
  14. Like I said I've done a poor job explaining it. Maybe someone with a better engineering background can make it more clear.
  15. So make it 4 times stronger, no big deal. I don't know the true numbers, but if you doubled the diameter of a carbon strand rope, you would more than quadruple the strength and just double the weight. Just looked up amsteel-blue as an example. 1/4" breaking strength 8,600. 1/2" BS 34,000. This dynamic would apply to all sorts of components on the craft. if your logic was correct, we wouldn't be seeing 72' winged cats sailing around... It's not logic its engineering and math. This is why you can make a paper airplane but a glider has to be made out of fiberglass or aluminum. 72' winged cats are right at the edge of our current engineering technology. You can't really make it much bigger with that design. I might be explaining this badly, but it's a problem of engineering and size. A cat can jump from the floor to the dresser, 5 or 6 feet easily and jump back down. That's several times its body length. But an elephant can not jump 100's of feet in the air. In fact an elephant can not jump at all. Even if you scaled up a cat to the size of an elephant it would still not be able to jump to the top of the empire building, because all the materials, muscle, bone tendons don't double in strength when you double the size of the animal. A cat the size of an elephant could not jump at all. pun not intended.