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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.  

Joakim

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  1. Torqeedo leg comparative drag

    So you are comparing the 2/4 kW Torqeedo model to the newest controlled pitch Oceanvolt model (Servoprop). The lowest power available from Oceanvolt is 6 kW. Servoprop must be much more expensive than the standard Oceanvolt drive. Torqeedo recommends 2/4 kW models up to 4 tonne boats. I think 4 kW is too small for 4 tonne. Are the Figures 1 and 2 of the Torqeedo claim available somewhere? The claimed "average speed loss" of 0.56% or 0.04 means that the speed was about 7 knots. Yes the loss will be low at such a high speed for a 30' boat. I don't know any Dehler 30', but looking at Dehler 29 it reaches 7 knots only between 75 and 135 TWA at 14 knots. At those points the speed difference between standard drive (VP or Yanmar) and no drive is less than 0.2% according to ORC VPP. So even if the Torqeedos claim is true, the drag is about 3 times more than the drag predicted by ORC VPP for normal drives. It is expected that the speed loss will be low when the boat has a high drag due to moving over its hull speed (about 6.9 knots for Dehler 29). Beat VMG at 14 knots wind is predicted to drop 0.6% and at 6 knots 1.4% (VP/Yanmar ORC VPP). These points Torqeedo will be addiotional 1-3% slower, if the Torqeedo claim is true. Torqeedo drive hub doesn't look at all well designed for low drag. The frontal area is huge (due to motor inside the hub), the tip looks too blunt and the diameter reduction towards the propeller hub way too fast causing flow separation. You can find the drag formula used in ORC from the VPP documentation (6.22). Note that the hub diameter (ST4) would be taken to be the end diameter, which is equal to propeller hub diameter. More realistic for Torqeedo would be to use the maximum diameter of the hub. The latter part of the drag area formula is dominent (0.4*(0.8*ST4)^2). For normal drives ST4 is from 85 to 112 mm. What is the maximum diameter of the Torqeedo hub? 200 mm would give 4 times more drag than 100 mm with that formula. Oceanvolt drive looks like to be as low drag as the normal drives.
  2. justice

    I think the wording is very clear in the current rules. If I remember correctly, it was way less clear long time ago (tack finished?). It would be very bad, if it involved sail trimming. What would happen, if a sheet is broken or slips through? You are tacking untill you got the sheet fixed? How tightly trimmed should the sails be? Usually it is very easy to say what is close hauled, at leas with 5-10 degree accuracy.
  3. justice

    Are you saying that everybody making a leebow tack are breaking a rule? It was just a normal leebow tack, which I have made very often with this boat and the wind was light (maybe 8 knots, boatspeed about 4 knots) with almost no waves. The only problem was in the communication and both boats changing course at the same time. I never asked can I cross and he clearly said he ducked only due to having waived me to cross. Most likely he had to duck more than he anticipated due to me tacking instead of crossing. If he had not changed course he would have ended on my windward side like I planned. So I did tack early enough, but got very confused about the situation after the tack and wondered if I had mistimed the tack very badly. If you do a leebow tack too late and close, a normal case would be that S has to luff before you are on close hauled. If the other has to duck the leebow, it's no longer a leebow. It must be straight ahead or a bit to winward. WO vs. C case seems to be about straight ahead and C could have ducked as well but chose to luff. In my case S must have started ducking about the same time I started to tack. S ended on my leeward side and bow around our mast and I was able to roll him. I think S heading down while P is keeping clear by tacking is breaking 16.1. P can't do more than a tack and if that tack was keeping clear S is not giving room for P to keep clear, if S steers towards P while P is tacking. Remember keeping clear means that S can keep it's course. It does not include S changing course. When S changes course P needs to keep clear with that new course, but S needs to give P room to keep clear.
  4. justice

    I don't know how "hunting" is defined in sailing slang, but 16.1 does apply to crossing and leebow tacking. A crossing boat is keeping clear, if the other boat can keep its course. And the same with a boat making a leebow tack. If S then changes course so late that P can no longer continue to keep clear, S breaks 16.1. E.g. if it luffs while P can no longer tack or heads down while P has already started the leebow tack (which would have left enough space had S kept her course). I'm not saying this is what happened hear and the facts found clearly state that C did not change her course untill she had to luff according to rule 14. I once had a quite interesting incident while trying to do a leebow tack. Luckily no contact and the boats were only 6 m. I was on port and S was close to layline maybe 200 m from mark. I decided to do a leebow tack and did that. However after the tack I found S on our leeward side. I didn't quite understand what had happened, since I was concentrating on the tack. S did not protest and is a friend of mine. I made the mark and S did not. At shore I went to apologise and ask what actually happened. He told me he had waved be through and ducked. I had not noticed the waving and ducking must have started at the same time I started the tack. I naturally had looked carefully at them to time the tack, but not during the tack. He said there was nothing to apologise and he also won at the end. I quess I didn't break any rule and neither did he. Had there been contact it would have been a tough case for the jury. I have often wondered what would happen if S waves you through and then doesn't duck or ducks and makes a protest. There is nothing about waving in the rules, but maybe rule 2 comes to play. I quess S could always claim that they were not giving any signals to P just some internal communication. Any jury decissions about that?
  5. justice

    You can't know that based on the jib. How do you know if it was already trimmed all the way in? Closed-hauled is a course. You can be on close-hauled wiht both sails flogging.
  6. justice

    They did loose several places in IRC and ORC (well, only one place in IRC div O). This is a handicap race and Ichi Ban is the winner, not Commanche!
  7. justice

    The minum penalty in SI is 5 minutes not 5%. However I think even 1 hour was a really small penalty in this case.
  8. Sydney to Hobart 2017

    If you are refering to me, I'm quite far from a WOXI fan boy. I'm just interested in the rules. I'm sure IJ made the correct decission and think one hour was a really small penalty for breaking rule 13.
  9. Sydney to Hobart 2017

    I'm not saying there was 4-5 m, that's just what Richo said. At what point is that picture? How many seconds after WO finished their tack? I haven't seen a video from which you could really see both the distance and the time of tack finished. I would be generally interested what is the required time or space between the boats for not getting a penalty from rule 13 or 15 in those conditions. What would your estimation be for the speed of WO after tacking?
  10. VPP calculator online

    It seems I got the "hiking crew" wrong. It must be number of crew hinking not kg. With that fixed the high wind speed are about OK, but 10 kn and 6 kn are too low. 45 TWA at 10 kn should be more than 6 kn and at 6kn about 4.5 kn. 150 TWA with spinnaker at 10 kn should be about 6 kn and at 6 kn about 4 kn.
  11. VPP calculator online

    Have you done any comparison to other VPP programs or measurements at sea? I did a quick comparison using Dufour 34 Performance. Unfortunately the result was not good. With default values + "racing sails" the light wind speed was way too low. Then I noticed a fixed blade propeller and clearly wrong values for keel and rudder. After fixing those the light wind speeds were still too low, but now the high wind upwind speeds became way too high.
  12. Sydney to Hobart 2017

    I was replying to armchairadmiral who thought that some juries make bad decissions and appealing should have no fee (there is no fee around here). So if a "bad jury" made a decission of no penalty, but stated there was 4-5 m between the boats an appeal could lead to a penalty by making a different conlusion from the same facts. 9 knots is 4.6 m/s so C would have advanced that 4-5 m in one second. But WO was moving too. Maybe 5-6 knots after the tack and accelerating? So the speed difference was perhaps 3-4 knots and thus 2-3 seconds to collision. How much is enough time for avoiding? But the facts found state they were already on collision course before the tack. That must mean tacking right in front left no space at all when the tack was completed. So IJ didn't seem to agree with the 4-5 m.
  13. Sydney to Hobart 2017

    The problem is usually the facts found and you can not appeal about them. E.g. in this case the facts found state that C luffed to avoid a collision before WO completed her tack. If the facts found would have been that WO completed her tack before C luffed or needed to luff and thus WO broke no rule, no appeal could change that. I was one of those who thought it is not obvious that WO has broken a rule. I don't think that it is possible to see from the three videos that have been publicly available how much room there was between the boats when WO completed her tack or would WO have been able to cross. Jury certainly had more video material, witnesses and likely instrument data. Later someone from WO said it was 4-5 m, which is not that much. How much would be enough in daylight and not that rough conditions between two 30 m boats driven by world class crew at 9 knots? 10 m? Or even less. If the facts found would have said there was 4-5 m between the boats, then an appeal could have changed the decision based on that fact. Of course not in this case, since there is no appeal from IJ decissions.
  14. Sydney to Hobart 2017

    The values I gave were measured by a Magizine comparing these three marine engines. WOT was at full speed and 4000-4250 rpm. The consumption at 2000-2500 rpm depends on how much power is taken from the engine, which could be anything from a few HP to 150 HP or even 200 HP for these engines. The consumption will be about 0.2 l/h hor each HP used. I have no idea how many HP the on board hydraulics (and charging) takes.
  15. Sydney to Hobart 2017

    Just looked at some test results of Yanmar, Cummins and VP engines in the 250 HP range. On idle 1.2-1.5 l/h and at full power 50 l/h. What do you mean by "10-13 litres per hour full load"? 10-13 l/h equals to about 50 HP output from a diesel.