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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.  

Moonduster

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  1. It's neither harsh, nor a great intellectual exercise. It's complete folly. To believe you can extract TWD from COG, you don't understand anything about the wind triangle or the vector sum that is heading or course. Stepping back and looking at your choice of thesis, it's rather like having chosen to prove the earth is flat. It's an endeavor that has no merit and can bear no fruit. As an employer, it would be enough to tip a CV in the bin - the analytics aren't much use when connected to no common sense.
  2. I will evaluate multiple approaches for wind estimation There's a fine line between tilting at windmills and simply squandering one's life, but I believe this undertaking is squarely in the latter category. High end race boats invest multiple hundreds of thousands of dollars in attempting to deduce true wind speed and direction from apparent wind speed and direction combined with heading and boat speed data. In order to analyze sailing performance, data is logged at several hz and extensive effort is made to document the configuration including sails, appendages, crew, driver, sea state, bottom condition and much, much more. The net effect of these concerted efforts, undertaken by paid, trained professionals, is that we get a general sense of things at best. Often, the result of the analysis is that there is no result. This is the real experience of the very state of the art. To believe that you're going to reverse engineer true wind speed and direction from GPS track and polars is pure fantasy. To claim that this is a computer science undertaking is ridiculous. To have sold this to an academic advisor suggests that your real skills are in marketing.
  3. ^ There was a request for an iInterpretation 70 covering the system used by covered a system similar to that used by Blair (amongst a variety of alternatives) that was public, posted by me and discussed in the New AC15m thread. (No73?)
  4. Dobo, The Rule explicitly require that Competitors provide access to any and all information and/or equipment without exception, as requested by the Measurement Committee. To that end, Competitors in AC35 were required to submit detailed design documentation to the Measurement Committee well in advance of any actual sailing. The systems' design documentation required of each Competitor and the dates by which that documentation was required were detailed by Measurement Notice 2, which is public. Documentation submitted by the Competitors to the Measurement Committee per the requirements of that Measurement Notice was, and remains, confidential. In addition, the yachts themselves were available to the Measurement Committee for continuous, detailed scrutiny from months before racing commenced until after racing was completed. Blair's "device" was handled no differently than any component of any Competitor's yacht; it received the scrutiny required to determine the yacht's Rule Compliance.
  5. All else being equal, the angle isn't very critical. What should be evaluated is the combination of the hose run and the skin fitting. Your goal is to be sure that little accumulated water sits inside the skin fitting and that it can't back up into the hose and that does not block the hose. You always want a clear path for exhaust when starting the engine.
  6. Don't spend much time undoing twists, they probably won't come out as the cover is likely twisted on the core and the twists are all but locked in. Instead, end-for-end the line.
  7. Your incessant personal attacks suggest you're unable to construct a valid argument based upon the facts, which at the risk of repeating myself, are simple. The Rule is to be applied literally. One skilled in the art will appreciate the difference between: The electrical operation of a hydraulic valve; and The electrical operation of a linear actuator controlling a mechanically operated hydraulic valve They are different. The former was permitted by the AC72 Rule; the latter was prohibited. Similarly, the control input based upon the cant motion of the daggerboard relative to the yacht does not constitute manual input as defined by the AC72 class rule. The Protocol prohibited subsequent Jury involvement in the proceedings. What they may have found is speculation and is not relevant.
  8. Are you sure those units are seconds? If the manual says 1-10 seconds and the instrument has values of 0 to 999, I'm thinking those are 100ths of a second. Why not ask B&G?
  9. Yo, SS ... You're quoting from the AC35 rule in response to a discussion about AC34, kindly get a grip. And every single one of your attempts at counterpoints are similarly wrong.
  10. All the boats had control systems of approximately equal capability. ETNZ simply had the best user interface.
  11. TC, I don't understand your question about the Jury being prevented from reviewing? There's always a time limit on protests, it's nearly always the right approach. The Protocol had a time limit, it had expired. Was there something else to your question?
  12. Damping rates are a personal preference. Some like fairly high damping as they find rapidly changing numbers difficult to follow. Others hate even moderate damping because they feel like they're aiming behind the duck. Bottom line, you need to try and see. I'd recommend starting off with a low damping value (close to zero) and if it drives you nuts, crank it up until it doesn't drive you nuts. If you get above a second or two, then you're looking at the instruments way, way too much.
  13. Some simple facts: AC34, Rule 19 was unequivocal in stating that, paraphrasing: Only manual power shall be used for the adjustment of daggerboards; except that electrically operated hydraulic valves or winch clutches are permitted provided that such valves receive any no external input other than manual input The diagram provided as part of Request for Interpretation 49 shows a mechanically actuated valve operated upon by the compound effects of: An electrical actuator operated ostensibly by manual input; and The relative motion of daggerboard cant with respect to the aforementioned electrical actuator Based upon those facts, there are a few simple observations regarding Interpretation 49: A linear actuator is neither a hydraulic valve nor a drive clutch; it is prohibited The relative motion of the daggerboard and the yacht is not manual input; it is prohibited In each of these two ways, the findings of Interpretation 49 contravened the AC72 Rule The Jury was prevented from reviewing the Interpretation due to time limits imposed by the Protocol Whether the Jury would have changed the findings of Interpretation 49 is neither clear nor relevant Some things to consider: Oracle cheated during the ACWS lead up to AC34 The findings stated that the team had a "culture of cheating" The Measurement Committee's Interpretation 49 contravened the AC72 Rule This is neither the first nor the last time that a Measurement Committee has reached an erroneous conclusion that has had material effect on the outcome of a regatta Oracle's feedback mechanism as implemented was permitted; Measurement Committee Interpretations are binding Oracle's use of the feedback mechanism described by Request for Interpretation 49 cannot be described as cheating Oracle did not win AC34 by cheating, they won AC34 primarily because they got lucky with Interpretation 49 New Zealand lost AC34 primarily because they got unlucky with wind and time limits Sailing has always included significant elements of luck The controversy surrounding the outcome of AC34 has far more to do with Oracle's cheating during the ACWS than with the details of Interpretation 49 or either teams' luck. Whether this is fair or just is immaterial. Claiming Oracle cheated during AC34 is baseless Denying Oracle is tarnished by their "culture of cheating" is naive Its well past time to move on Some of us would prefer that the incessant rants on this topic be conducted in the threads dedicated to this topic rather than strewn all over the site
  14. Thanks for the update. As is often the case, the right question isn't "Why did it fail", it's "How on earth was it working at all". I would expect those blocks had stopped turning a long time ago. While manufacturers' specs are nice, they're very idealized and rarely include a working life. In that application, I'd think seriously about: Adding a safety line rated with a working load that's equal to the breaking strength of the backstay Sizing the blocks with a 5x safety margin Performing annual inspections Implementing an annual rotation plan that has you throwing out the most highly loaded block and moving more lightly loaded blocks into more highly loaded positions so that you're buying one new component per year
  15. Your second plan is the right one.