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      Abbreviated rules   07/28/2017

      Underdawg did an excellent job of explaining the rules.  Here's the simplified version: Don't insinuate Pedo.  Warning and or timeout for a first offense.  PermaFlick for any subsequent offenses Don't out members.  See above for penalties.  Caveat:  if you have ever used your own real name or personal information here on the forums since, like, ever - it doesn't count and you are fair game. If you see spam posts, report it to the mods.  We do not hang out in every thread 24/7 If you see any of the above, report it to the mods by hitting the Report button in the offending post.   We do not take action for foul language, off-subject content, or abusive behavior unless it escalates to persistent stalking.  There may be times that we might warn someone or flick someone for something particularly egregious.  There is no standard, we will know it when we see it.  If you continually report things that do not fall into rules #1 or 2 above, you may very well get a timeout yourself for annoying the Mods with repeated whining.  Use your best judgement. Warnings, timeouts, suspensions and flicks are arbitrary and capricious.  Deal with it.  Welcome to anarchy.   If you are a newbie, there are unwritten rules to adhere to.  They will be explained to you soon enough.  

samc99us

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About samc99us

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  1. A Class Worlds - Classic Division

    Per classic aero theory, yes. However one also has to remember that we are sailing in a boundary layer, and there is more wind aloft than at the deck of a 30' rig. On the foiler, one cannot accept the increased heel that the top of the sail generates in virtually any condition above 7 kts of wind speed, so the heads have become smaller and smaller, dropping below 800mm (look at latest Brewin and Mischa A-Cat DS's). Now compare these to what the latest F18 DS sails are using-they are in the 750-900mm range for the head size with pretty short foots, ~1m, which leaves a nice hole for tacking and gybing with 2. One doesn't quite need that on an A Cat but more space does make for easier maneuvering! Our opinion is the 2016 Glaser A-Cat DS, which has a pretty big head (I have the actual number somewhere, but IIRC its ~800mm), is a fast sail in up to 10kts of breeze. This is based on foiling test data but the non-foilers are very surprised at how well this works on the Hall Medium Flexi rig in the light conditions. I would happily recommend this sail to a classic sailor looking for a new sail. I am sure the Landy WnW has is similar.
  2. F16 like foiler?

    Good thing there are a lot of quality foilers coming onto the market. One nice thing about the A class is there are always a number of sailors buying new platforms yearly so good boats are available on the used market. There are at least 2 in the U.S for sale at very reasonable prices IMO that have the beams and boards in the right position.
  3. F16 like foiler?

    Per a DRAFT copy of the 2017 rules: C.6.1 REFERENCE WEIGHT The boat shall be weighed fully assembled, dry and clean. The mast will be laid flat across the platform in such a way as to achieve an equal distribution of its weight and to remain stable during weighing. The weight of the boat includes ALL items present on the boat in a ‘ready to sail’ condition excluding personal equipment and all portable equipment as listed in C.5. (a) The minimum weight of the uni rig boat in dry condition shall be 119 Kg (b) The minimum weight of the sloop rig boat in dry condition shall be 123 Kg C.6.2 Corrector Weights (a) Corrector weights of metal shall be permanently fastened to the front beam when the boat weight is less than the minimum requirement. (b) The total weight of such corrector weights is difference between the weight and the reference weight and shall not exceed 7 kg. See also rules A.10.1 and B.1.1.
  4. I'm making a rudder

    Did you actually build it? The prices quoted seem reasonable for a one-off elliptical rudder blade. Lowest price I could do that job for would be well into the $1000 price range. I think your best bet is to either re-use a rudder that someone else has done for a similar size production boat, or get some other S-2 7.9 owners together and get some molds cut. The amount of carbon in these blades can be staggering. I'm counting ~25 layers per side in a blade I've been working on on and off over the last year (its a 2nd spare, so not in a hurry to finish the job).
  5. Gitana 17 on Foils

    The board didn't break at the knee and they have tested it in more extreme conditions than the AC 72 foils; I suspect that it is thicker there for starters than what Oracle designed, and I also suspect it is solid at the 1/4 chord point, either with a full carbon vertical shear web or a metal insert. One of the issues if you just went to completely solid carbon is you may not get the plies in the correct orientation (i.e just laying a stack of uni carbon in the molds)...its preferable to have the shear web on the bias to resist the shear forces in the middle of the structure, otherwise the shear strength of the epoxy is doing a lot of the work, rather than the far, far higher strength fibers. Regardless I'm sure the issue will be sorted and they'll likely 'limp' back to France without the dagger foils and we'll eventually see her start winning races when the conditions are right.
  6. Macif / Gabart / Jules Verne 2017-18

    Yes exactly Popo, the photos show very little boat left in the water and heavy, heavy foil assist, hence my question.
  7. Macif / Gabart / Jules Verne 2017-18

    That's what I was thinking as well Wess, boat designed for full foiling, let it rip as is and sort out the foiling developments. I think Macif would be faster in lightly crewed mode like Joyon/IDEC went for. Faster than IDEC? IDK, at the moment both records are very tough to beat but I'm not sure if Gabart has ever not sailed solo down south. The big question is, is the autopilot faster than a human driver? The speeds are pretty incredible under full auto...I would guess manual trimming+auotpilot or pro driver would result in higher average speeds with the penalty that of needing crew. I think the real advantage the crew has are more hands to fix things when they break, if it weren't for the unforeseen breakages you could just automate the whole boat (personally a fun challenge, to build an autonomous maxi, but like most people I enjoy the human aspect of these preojects more than just building another robot).
  8. Macif / Gabart / Jules Verne 2017-18

    Looks like a good bit of lighter air for the next several hours at least? Also, isn't Macif pretty much full foiling, or did they pull the J-boards off for this record attempt? The speeds indicate heavy foil assist like Sodebo, and some of the shots sailing indicate very little boat is left in the water. Regardless, the speeds are incredible and this is exciting to watch!!
  9. Gitana 17 on Foils

    Depends on how you look at it, and in what condition you are evaluating. M&M show a high positive pressure on the inner foil skin at the leading edge, working its way back to a small negative pressure on the trailing edge. Of course we don't know the AoA of the board, sideslip angle, velocity or really much from this screen grab (which was also run on the N17 board package, not the Gitana package which could be different). Anyway, I'll stand by my point that the inner skin can see high positive pressures at the knee. It can also see high negative pressures. This is why these have often been formulated from very high strength tempered steel alloys, or full carbon.
  10. Gitana 17 on Foils

    Exactly. I would expect that to be Rohacell IGF110 or Nomex Honeycomb. Someone was trying to save a $1 in the wrong part of the build, unless I'm missing something and coremat is the secret to success?
  11. F16 like foiler?

    Scarecrow, Waynemarlow's information isn't incorrect. I believe the change is in this meeting report: http://www.formula16.net/2017/08/class-meeting-report-wgm/ I can't open it at the moment, but SCHRS also recognizes the increased weight: http://www.schrs.com/ratings.php At the moment its a big CF imo, hindered by the lack of a published set of class rules from 2016/2017.
  12. F16 like foiler?

    +1 for that. Check out the Bora Gulari report for more details. I also just heard of a pretty bad crash of a good sailor on a new to him foiling A.
  13. F16 like foiler?

    Lots of ways. For starters, the hull is closer to an F18 than F16, at 17' 9". Second, it was designed with foiling in mind for the start (Mk. 1 had C-boards). Third, the rig is carbon (most F16's are alloy) and taller than a F16 rig at 30'. Fourth, the 17 Mk. 2 is all carbon in the hulls, but still uses the F18 beam section. Fifth, the boat is a fair bit heavier, numbers I have heard are closer to 150kg. Finally, its an all-out foiler now with the only serious racing option in mixed teams at World Sailing/Olympic level events. It would be interesting to see what one would do in a Florida 300 or Race to Alaska scenario.
  14. F16 like foiler?

    Erwankerauzen, Last I checked Brett was running the show over at Goodall these days, I'm sure Greg is still around but maybe not in the day to day operations? They are certainly capable of executing this project from a build statement (no small undertaking I might add), but what foiling boats have the goodall family designed? By all accounts the N17 Z-foils are on the draggy side, and there may be some other foil design issues in that class, and M&M are by no means inexperienced foil designers with thousands of hours of AC experience plus the F20c and F20FCS build experience. My point is, its unlikely they will get this right out of the box. Maybe, but unlikely. The good news is, as long as the trunks are engineered to accommodate a wide variety of shapes, the upgrade costs for new foils in the future aren't too terrible (in line with a set of sails).
  15. Gitana 17 on Foils

    +1 to that. In the highest pressure part of the foil as well.