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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.  

Doug Halsey

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Everything posted by Doug Halsey

  1. Foiling Moth Setup

    I'm sure you've found several helpful videos. Here's a good one (even though it's over a year old) showing one of the more complicated setups. You don't necessarily need all the same gizmos, but it might help you understand more of what's going on.
  2. Astus Upwind

    Dashware doesn't have to take such a long time. If you start your video with a short segment showing the GPS time from your cellphone, the sync step takes almost no time at all. And if you only overlay the data on short segments of the video that you want to include in your edited version, that doesn't take long either. Here's one of many short clips I've made to help evaluate gybing technique on my Moth (Note: this is not me; it's someone who knows what he's doing).
  3. VPP for dinghies and skiffs

    GPS Action Replay gives an estimate of the TWA. Of course, its accuracy depends on having a big enough sample of data points & how steady the wind actually was.
  4. A-Class North American Championship by San Diego Yacht Club

    Granted, it's hard to say what the most important factors were, but it may not be a coincidence that the only 2 DNA F1's in the fleet finished 1st & 2nd. The attention to detail in the platform aerodynamics is very impressive. In contrast, the 3rd place Exploder was at a bit of a disadvantage, having torn his lower tramps on the 1st day & was sailing most of the series without them. But who can say how big a factor that might have been? And what about the narrower square-tops on the F1's? (See the blue boat in the earlier post by Lost in Translation)
  5. A-Class North American Championship by San Diego Yacht Club

    Just so this thread isn't left hanging, here are the final results: https://sdyc.org/assets/results/results17/a-cat-na-res.htm
  6. F18 ownership costs

    How many Moth sailors have shore crews? None that I know of in my club. F18's are great, and I don't want to say anything negative about them, but they're a lot more trouble than Moths in all sorts of ways.
  7. A-Class North American Championship by San Diego Yacht Club

    This is the "non-foiler" mentioned on the front page.
  8. A-Class North American Championship by San Diego Yacht Club

    Correction - actually it's in south San Diego Bay.
  9. Radio Control Multihulls

    Do you collect any data from your tests? Speed, at least, is easy to get since there are now small, light GPS units available. Getting forces might be more difficult.
  10. Sail twist simplified

    That's really not very good advice, BobBill. Beauty is in the eye of the beholder & I'm sure there must be some who think this Snipe's sails "look good".
  11. Sail twist simplified

    What assumptions did you make about the velocity gradient in the Earth's boundary layer. In other words, what was the difference in true wind speed & over what distance?
  12. Smyth Wingsail via Jim Brown

    What's a Cb?
  13. Foiling in shallow water

    Mach2.3 Vertical is ~41 1/2", measured the same way. The older Mach2 vertical is ~2" shorter, I believe.
  14. The winning foils

    I find it pretty strange that you're using the past tense & referring to Moths as "ancient foilers." The class is doing just fine in many parts of the world, and the boats & foils continue to evolve. Nevertheless, I'm curious about Gacking too. I know it has been done in the Moths, but I wonder how common it ever was & whether its use has diminished as the best sailor's ability to do foiling tacks has improved. It would be pretty incredible to see one of the AC teams pull it off though!
  15. Odd Weather/Lee Helm

    The SpeedPuck (like the other Velocitek products) stores a file that can be downloaded to a computer & analyzed in software like GPS Action Replay to display the boat's performance. If Tom would make at least one of the Astus's files public, that would help a lot in evaluating his speed claims.
  16. Steve and Dave Clarks Unidentified Foiling Object

    When I tried to get insurance from BoatUS for my Moth (3 years ago) , they told me they wouldn't insure any boats with hydrofoils. Try Gowrie Group.
  17. Skiffs in San Diego

    Sorry about that! I know the 14's are great boats & I'm glad to be wrong in this case.
  18. Skiffs in San Diego

    I don't think you'll come across many I14's in San Diego, but we've got an active & growing bunch of Moths at Mission Bay YC. Currently ~8 Mach2's & several older BladeRiders. 6 mph would be a very light-air day; more typically around 10mph or more in the afternoons. Enough for >20knot boatspeeds most days. Lots of fun! And rotating masts & other innovations are definitely allowed.
  19. The winning foils

    You don't have to consider cant angles & leeway to find examples where having a slight V can be advantageous. It's an established fact (backed by both experiments & numerical calculations) that the induced-drag efficiency factor improves as the angle of V increases. At higher speeds, the increased wetted area & possibly sooner tendency to cavitate make the V foils have more drag. But at lower speeds, the induced drag becomes more dominant, often resulting in smaller total drag. So, it's not really surprising that the light-air foils might have more of a V shape.
  20. The winning foils

    From the Racecourse description: "Please note: Racecourse orientation and length may vary based on wind direction & strength." So you can bet we'll see some shorter courses in lighter winds. My question is whether there is any minimum length for the course?
  21. BAR is a dangerous Motherfucker thread

    And might some of them already be prepared to do that?
  22. BAR is a dangerous Motherfucker thread

    Since the helmsmen can control the foil incidence, shouldn't they be able to help avoid this situation in the future by learning to reduce the AOA whenever they round up?
  23. Means of propulsion

    I'm not sure exactly what the research shows, but you only mention generating more lift. So, what about conditions where the boat is fully powered up & they need to trim to minimize drag?
  24. Centerboard Vibration/Hum

  25. Queensland A class championships

    I do appreciate your comments & was just making a lame attempt at a joke. I'm not really as grumpy an old man as I sometimes seem.