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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.  

sosoomii

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About sosoomii

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  1. VPP for dinghies and skiffs

    Well, I made it up... I took the 59er drag curve and amended by nothing more than judgement - less wetted but shorter length etc so less draggy at low speeds and more (much more) draggy as speed builds. Aero model is essentially the same between both boats, but with the right sail areas and some allowance for the 59er sails being v flat in comparison. I know the 200 looks too fast, maybe I need to add even more drag. Or it may be that the 200 rig is much draggier/less adjustable than I allowed for. But if you take the ratio of the VMG at 45 degrees, you get pretty near the ratio of their PYs, so maybe it isn't that far off after all.
  2. VPP for dinghies and skiffs

    This polar shows the difference between an RS200 and a 59er (chosen because they are opposite ends of the hiking asymmetric spectrum and the 59er drag curve is available in HPS2). The 200s VMG downwind is pretty consistent across the angles, giving a choice as to whether to soak of go for speed, depending on tide, fleet position shifts etc. The 59er is much spikier, as the kite can't be carried too high and speed drops off quickly if pointed too low. Get it right though and you can go downwind at windspeed, and stay in a gust for the whole leg.
  3. VPP for dinghies and skiffs

    Sure it does, you can't hold the kite at a TWA of 110 degrees
  4. VPP for dinghies and skiffs

    Cool.
  5. VPP for dinghies and skiffs

    I think that is a very puritanical definition of a VPP. A VPP just has to be able to predict a boat's velocity. If it can do that using a limited number of parameters that represent the design, then great – but it is not a requirement. A VPP is just a balance of forces calculator; if the drag force of the hull can't be calculated then it is a perfectly reasonable approach to use a lookup table based upon tank tests or towing trials or reading tea leaves. And in this sense it is far easier to estimate the drag force of a fully foiling boat than a semi-planing boat, because foil drag as a function of speed, angle of attack, aspect ratio etc. is well characterised in the literature and more readily analysed using CFD techniques.
  6. VPP for dinghies and skiffs

    Exactly. The resistance of a foiling Moth would be relatively simple, and the single sail is also the simplest thrust device. No worries about interaction between sails, or how to characterise planing etc.
  7. VPP for dinghies and skiffs

    A VPP for a Moth must be the simplest. I'd imagine someone must have developed one for them?
  8. VPP for dinghies and skiffs

    I think they are largely of academic interest in dinghies because a. They are likely to be wrong* and b. You don't know your true wind angle. Generating them can be fun though as it allows you to virtually sail the boat and look at the sensitivity of sail settings and heading etc. * The 49er ones linked to, for example, suggest best VMG at 70 degrees TWA. Presumably the units are m/s rather than knots too, else they're very slow!
  9. VPP for dinghies and skiffs

    RS400. Not validated.
  10. The difference between the Aero 9 and the Laser is much less than that. The RYA PY numbers are 1024 and 1097 respectively. At that rate, if the Laser is doing 15kt, the Aero is doing 16kt. An improvement yes, but the difference between boredom and excitement?
  11. Live Racing Thread

    Good thing ETNZ is a quick boat. Burling doesn't seem in Ben's league re sailing skills.
  12. Live Racing Thread

    How many do they have to win in the semis?
  13. Will Larry replace Jimmy with Peter?

    Moths are most definitely not OD at the front. I'm not going to defend Jimmy but his AC record (the one that really matters) isn't shabby. Don't remember Ben, Giles, Iain doing the Moth worlds? In the 1980s Worlds may have been harder, but these days just qualifying for the Olympics is harder if you are from a top sailing nation.
  14. Will Larry replace Jimmy with Peter?

    One design moths, eh? Whoever knew that? It's not even an Olympic class, so hardly the creme de la creme worthy of putting on your CV. And just the one Olympic medal? PB is a good sailor no doubt, but actually better than the others? Hmmmm.
  15. Live Racing Thread

    Yesterday some here were claiming Burling to be the greatest sailor of the bunch, now he doesn't even have a Plan B? Gotta love Kiwi level headedness.