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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.

us772

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About us772

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    Anarchist
  • Birthday 10/20/1962

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    https://groups.yahoo.com/neo/groups/wingboats/info

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  • Location
    Mt USA
  • Interests
    Build and sail fast stuff- Dirtboats iceboats catamarans windsurfers
  1. I was wondering how the AC wings keep from having flutter or oscillation issues with the wings since they don't have positive control systems. Do they have a dampening system to prevent it? Think of wing oscillation as a luffing sail. It is driven side to side by the wind. Usually to self destruction. This can happen to us even parked. I learned this the hard way on my first wing attempt in the 80's. 3 month s to build and 3 seconds to destroy. Here is an extreme example of wing oscillation. This isn't a solid wing just a deep wing mast without the sail on in high winds. He was radared at 78 mph as it unfolded. The spar was controlled by a 3/16'' ss cable connected to a mast rotation limiter. It snapped after he lifted a wheel and sheeted out allowing the spar to oscillate.
  2. On good smooth hard ice it easier to sail in less wind than on a drylake bed. Less friction and air density may play into that.
  3. I have studied apparent wind using a formula based off a windsurfer theory on my winged dirtboat. Keep in mind my wings are only 20 to 24' tall. So less wind gradient. The vectors Ive come up with are about 3 to 4 degrees in max wind limit conditions for racing. Around 30mph going down wind around 85 mph. The windier it gets the more difference in angle. Diminished gains in speed as it gets windier due to drag or lateral resistance. Upwind the angle is about 2/3rds of the down wind angle. Over the years I've used almost all my different dirtboats as iceboats too. When Ive had a gps on the top speeds are almost identical. Its hard for some iceboaters to digest that.
  4. I build and race solid winged dirtboats. Our rules in the US allow open design based only on sail area. For a high aspect wing design to work optimal more righting moment is needed. Our boats are usually wider and longer to compensate. It's hard to get the most out of a wing of the rules don't allow wiggle room for righting moment. Anyone know what section shaped were used on the Smyth wing?
  5. I've been building and racing solid wings with an external slotted flaps similar to those used on the current AC 50's since the late 80's. I use them on landsailers and iceboats. Closing the gap. - I've found that what we call closing the gap at the bottom of the wing makes them go faster. It helps clean up the vortex that occurs at the bottom of the wing. It appears all AC boats have them (Gap Closers) by looking at the video's. Part of the one design wing package I assume. The slot - the slot or gap when the flap is angled opens up more when the angle becomes greater. The amount of gap can be changed by moving the pivot point for and aft in the trailing edge of the first element. I design mine to have an optimum shape at 20 degree flap angle. That means the lee side of the wing and flap have no abrupt changes (smooth flow). I find with a 12% thick flap multiply its chord length by 13%. That is the distance of the flaps pivot point forward of the main elements trailing edge. Its better to error on the smaller side than the bigger with the pivot point location. I'm not sure if the pivot point location is One Design or open to choice on the AC 50's. Twist - In the land sailing/iceboating world excessive twist is slow especially to weather. We get instant feedback while landsailing so if your doing something right or wrong you feel it right away. I use whats called positive control on my wing to change the angle of attack. I can sheet it in or out with no slop in the system. I can actually back wind the wing to act like a giant air brake = drag. Occasionally this can happen on accident in the middle of a tack. You really feel the boat slow down if the timing is off going through the eye of the wind. Based on that I'm some what skeptical of what people see as inverting( back winding) through excessive twist the top of the AC wings for more righting moment. That would cause a lot of drag.The AC wings seem overpowered once hooked up at speed so they need the twist to keep the thing under control. Another benefit of some twist is reducing the tip vortex = less drag off the top. I think there is a fine line between over twist and under twist. Who ever gets it figured out best will prevail. brilliant summarizing. Thats where the regatta will be won!... by the engine not the tyres! Thats where the regatta will be won!... by the engine not the tyres! I should of said the wing trim is only one piece of the whole package that will win. Artemis's foiling ability looks pretty impressive so far!
  6. The photo was captured at the start of the practice race when Oracle retired early from this video - The apparent wind is a more because our speeds are a little higher than the AC boats. That makes the difference of wind sheer less important because it is less of a percent from top to bottom. Our wings are not that tall either compared to them so wind sheer is not as big of a factor. I figure through the use of vectors 4 degrees of twist is about all you want in my world. I have the ability to take off the tip section for high winds. It lowers the ce and area. It's faster because the RM improves meaning you can sheet in the wing where its has full drive.
  7. USSR rigid wing fleet
  8. Sorry for the temporary hijacking of the tread. Here is some history on how the use of wings got started (at least in iceboating and maybe sailing in general). The first mention of a rigid wing dates back to 1927. German or Estonian ? iceboat design. That same year Estonia and Germany organized the first official European iceboat racing. USSR had a lot of them racing and formed their own separate 12m and 8 m classes after WWII. Pictured 1- 10m rigid wing. 2 - What appears to be the first rigid wing with a flap 1950.
  9. A view of twist between Oracle and Artemis at the start of the race.
  10. I've been building and racing solid wings with an external slotted flaps similar to those used on the current AC 50's since the late 80's. I use them on landsailers and iceboats. Closing the gap. - I've found that what we call closing the gap at the bottom of the wing makes them go faster. It helps clean up the vortex that occurs at the bottom of the wing. It appears all AC boats have them (Gap Closers) by looking at the video's. Part of the one design wing package I assume. The slot - the slot or gap when the flap is angled opens up more when the angle becomes greater. The amount of gap can be changed by moving the pivot point for and aft in the trailing edge of the first element. I design mine to have an optimum shape at 20 degree flap angle. That means the lee side of the wing and flap have no abrupt changes (smooth flow). I find with a 12% thick flap multiply its chord length by 13%. That is the distance of the flaps pivot point forward of the main elements trailing edge. Its better to error on the smaller side than the bigger with the pivot point location. I'm not sure if the pivot point location is One Design or open to choice on the AC 50's. Twist - In the land sailing/iceboating world excessive twist is slow especially to weather. We get instant feedback while landsailing so if your doing something right or wrong you feel it right away. I use whats called positive control on my wing to change the angle of attack. I can sheet it in or out with no slop in the system. I can actually back wind the wing to act like a giant air brake = drag. Occasionally this can happen on accident in the middle of a tack. You really feel the boat slow down if the timing is off going through the eye of the wind. Based on that I'm some what skeptical of what people see as inverting( back winding) through excessive twist the top of the AC wings for more righting moment. That would cause a lot of drag.The AC wings seem overpowered once hooked up at speed so they need the twist to keep the thing under control. Another benefit of some twist is reducing the tip vortex = less drag off the top. I think there is a fine line between over twist and under twist. Who ever gets it figured out best will prevail.
  11. Ya, we're definitely working from opposite ends. With no size limit, windsurf rigs are designed to break thru the planing threshold as early as possible, and then dispose of the excess area as efficiently as possible IE with minimum drag. But another analogy to consider is that foiling has a similar 'downward step' in the drag vs speed curve (planing threshold for windsurfers, foiling threshold for AC boats), and recovering from any incident that knocked you off the foils would require instantaneous power to minimise the cost in a race. This was where ETNZ had a huge advantage over OR at the beginning of AC34 - their designers had anticipated this as shown by their decision to incorporate LE twist, and their wing was trimmed much more like a windsurf sail at the regatta outset - I had the privilege of watching the first races from a boat, and the difference was obvious and extreme. Basically, it breaks down to how 'powered up' the new boats are. If they are producing power beyond the righting moment limitations of the boats, then you could afford to dedicate the upper section to being reactive to gusts, whereas if they need to extract every last bit of HP out of the permitted wing area, then that's what you would do. Looking at the boats (at least in the stronger winds in recent videos) I think it is the former - they have power to spare. Check out the last 5 minutes of this video describing Oracles comeback. - It sounds like their main issue was leeward helm. The wing engineers corrected the problem by raking the wing back even though it screwed up there sheeting system. They had a faster boat the whole time. It just wasn't tuned correctly.
  12. I would assume it's common to have the bows go down during a bear away as the rig loads up on any multi hull? Why would Oracle bear away when the leeward hull is just skimming the surface? The second it hit the water boat slows down the AOA changes on the wing = game over. See skimming 29 seconds in.
  13. If I didn't live here and wanted to come, I would be doing the cruise ship option. I've followed AC afloat and ashore since '67. Over a 50-year span countless days on the water for training, LV and AC. Worth noting that with the advent of television even a great position in the spectator fleet means the bulk of floating passengers cluster around the TV and only go on deck at the rare times that the competitors get close. These days I'd settle for a few days onsite including a day or two on the water to soak up the ambiance. Then retire ashore to big screen TV and Liveline analysis. I'd jump at a chance to sign up for your Norwegian cruise. The only thing stopping me is the big bucks for airfares X two from Auckland to Boston Of course it will be easier for the next match. I can just go up to North Head! Yes I want to be in the atmosphere in the AC Village. We will hanging around the big screen or laptop there and the occasional glance at the finish. Most likely hard to view otherwise.
  14. A few years back I made the first Mini Skeeter iceboat. One of the reasons I made is that it's easy to transport and setup. Because of that we've been able to explore different places to iceboat on a moments notice. This year has been the coldest winter I've experienced since moving to Montana in 95. The bays on Flathead lake have been frozen for 3 months. Unfortunately we are experiencing record snow fall as well delaying the start iceboating season until the last 3 weeks. We live in a spectacular place to enjoy the sport. It's next to miraculous to get all the elements of hard snow free smooth ice and wind to come together as one to sail. I recorded a few of our trips traveling across Montana and sailing some local ice on Flathead Lake that we've never sailed before. I will typically set up a windward leeward race course. We fun raced for hours until our arms were noodled. Yesterday I sailed out to the windiest part on Big Arm Bay with the drone in tow to try my hand at recording some video. I followed some of the iceboats around for a while recording them. After doing that I flew the drone and pointed it to record where I was standing next to its carrying case. Drone In the air I put the controller on the case and got into my iceboat and sailed around and recorded the action. - Good Times!
  15. My wife booked a cruise there for us there For the LV. The cruise ships dock next to the AC Village and the finish line. May be a good vintage point to view from Cruise ship height? She chose Norwegian. They Go out of Boston arrive in Bermuda at 1pm.Sunday then stay until 5:30 Tuesday. Racing is scheduled 2 to 4pm and 2 to 3:30 pm. on the days we chose. I felt to get the most out of the racing events that are on 3 consecutive days pending wind conditions May 28th - 30th for the LV not the AC final. 10 races scheduled in that time frame. The next best time frame that works for that cruise ship itinerary is June 25- 27 for the AC final races. On the later dates there is a chance of the challenger or defender walking away with the thing and there would potentially only be one day of racing. Food, lodging, transportation taken care of and proximity are good. We booked ticket for AC Village about $30.00 per day. Another iceboat/ landsailing friend and wife coming along too. The cruise rates range from $870.00 on up PP. plus $ to get to Boston and back. Norwegian rates - https://www.ncl.com/cruises/7-day-bermuda-round-trip-boston-DAWN7BOSWRFBOS/Dates/May-2017-to-June-2017?destinations=4294961649&numberOfGuests=4294953449&state=null&sailmonths=4294953391+4294953392&&itineraryCode=DAWN7BOSWRFBOS Race Schedule - https://americascup-images.s3.amazonaws.com/original/m2287_2017-louis-vuitton-america-s-cup-schedule.jpg