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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.  

Erwankerauzen

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About Erwankerauzen

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  1. It seems the big wing mast prototype did not attend the Polish championship! did it?
  2. Hi Mates, A few ° rake is not a good reason enough to fight on the forum, d'ont you appreciate this peaceful atmosphere without Doug getting on the nerves of everybody with his uptip obsession??? It is Holidays for Anarchists, just enjoy!!! If I wish to get a few relevant numbers for the mast rake, just to see how much the sail CoE will move forward with a wing instead of a teardrop mast + sail. The wing has no leech and pulley block to retain the rig to move alone forward, so a minimum rake is required from the design table. But if classic rigs allow good foiling with 0° aft rake, I am f&#ked, the idea would not be that relevant But with 3.5° to 4 ° aft rake, a wing will allow to move the foils closer to the main crossbeam That is just insane curiosity, Thanks to all
  3. if the hound is at 6 meters height , and the shroud attachement 50 cm behind the mast foot. then at 5° the hound is aft of the vertical of the shroud attachement on the gunwhale.. I was expecting something between 0° and 4° ???
  4. Has anybody a idea of what kind of mast rake is used for the foiler in middle wind condition ? If in ° it would be great. Happy world for the lucky attendees
  5. MultiThom, You are perfectly right, I mentionned figures from memory, and my Alzheimer mislead me: Windward with 13knts TWS and 45° TWA with boat sailing @ 13knts at 18 feet height AWS is 24 knts and AWA is 22.5° at 6 feet height AWS is 21.6 knts and AWA is 19.86° at 2 feet height AWS is 19.3 knts and AWA is 16.58° Downwind with 13 knts TWS and 115° TWA with boat sailing @ 17 knts at 18 feet height AWS is 16.4 knts and AWA is 45.6° at 6 feet height AWS is 15.74 knts and AWA is 36.8° at 2 feet height AWS is 15.42 knts and AWA is 27.3° In the same conditions for a foiler sailing around 20 knts windward and 26 knts downwind twists are reduced by circa: 40% . Happy Sunday
  6. Sorry, I am not a digital native, I guess you can rotate the picture by 90°
  7. Multi Thom, It is only about turbulent BL
  8. From Bethwaithe graph With 10 knts TWS @ 18 feet height TWS is 6 knts @ 2 feet/ 7.5knts @ 4 feet
  9. I used a proxy function to mimick and extrapolate the Frank Bethwaite graph, it was a kind of polynomial regression which fitted perfectly the gradient above 3 feet height and overestimated the TWS speed below. When you must extract as much a possible HP from a maximum sail area, like it is the case for C-Cat and A-Cat, it is a bit different than for "Yatching" & "Champagne sailing" on big monohulls with Marconi rigs. Gradient , both windward and downwind, must be considered, just to check is there is something to be optimized, I have been always very disappointed by generalities heard here or there on catamarans parking, so I always make my "fact checking" and on this point, I believe that gradient worth to be considered even above 6 knts in turbulent BL.
  10. I am not sure for the Floater Downwind the true wind angle was actually 115°, probably 125° or 135° but I can t find the xls spreadsheet.
  11. I extrapolate the wind gradient as plublished by Franck Bethwaithe in his book "High Perfprmance Sailing". But I have used also the Log formula which is a classic proxy used by engineers. I guess you can find it easily with Google
  12. Tkx, I will sniff around Scheurer's websites
  13. Any available workpaper regarding the drag test above mentionned ? Thanks in advance
  14. A few figures for an A-Cat: 1-The Floater case (13/14 knts TWS) Windward, sailing 13knts @45° of TWA, the apparent wind total "twist" will be in the 7° to 8° range Downwind sailing 17knts @115° of TWA the apparent wind total twist is around 17° 2-The Foiler case (13/14 knts TWS) Windward foiling 20knts @ 48° of TWA the apparent wind total twist will be around 5° Downwind foiling 26knts @ 115° of TWA the apparent wind total twist will be around 10° So if you foil you have to pull the mainsheet harder, everything else equal. Incidentaly, if you have a small teardrop mast it will manage the big twist for the floater case without any problem, while a large chord wing mast would not. But if you are a foiler, the apparent wind twist is smaller and a large wingmast would not be penalized, while the big mast chord would improve the windward separation behind the mast and decrease the section drag accordingly. With these apparent wind velocities, low aero drag is king. Good Week-end