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#16
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As to skeg hung rudder. I was a skipper on 46 feet sailboat for 5 years. she had LWL 11.5m keel 5m long wtih 2m draught, 0.8m of them in the hull, and skeg hung rudder. On the 5th year, I used to lash the helm 5minutes after sails are set and trimmed, when sailing upwind. My personal record is 12hours against force 5 and 2 m waves with lashed wheel. It was in Baltic, where waves are short and steep. Adjustments (a few degrees of wheel movement) were made once in an hour or so. So I suspect that constant corrections you mention about HR46 were caused by some improper sail trim. Most good sailboats are able to selfsteer upvind or close reaching, no matter if the keel is full, or if the rudder has a skeg or not. As an example, (I talk from personal experience only) an 43 feet IOR dinosaur with masthead rig, and balanced spade rudder did sail for 10hours upwind, against force 4-5, and sea state to match, until wind abated to force 3. Then she made a tack by herself, and crew decided to hand steer from then on . So for ease of steering (I mean if a boat could sail with helm lashed, she will not tire the human or electric helmsman too ), balanced hull lines, proper sail configuration and proper sail trim is far more important as configuration of keel and rudder.As to heavy wheather. Once, we were caught at sea (SE Baltic) in REAL storm with 8.5m boat. Some shore stations reported Force 9... our estimation of wave height was 4-5m. With all the reductions for low vantage point and scared eye deducted. The boat was a resurrected from scrap Dragon -wooden, 0.5m of stern sawn off, 15cm of freeboard added + small cabin, so you could just sit inside. At that time, we decided not to heave-to, but sail a little closer as beam reach, so that wave caps break at the bow, not to the cockpit. The blow lasted for 12 or 15 hours. All the time we spent inside, with line from the tiller lashed to convenient point. Adjustments were again made once in an hour or so. How much credit there is for actual configuration of keel I am not sure. We tried to heave-to with this boat several times in moderate weather, when a having a surplus of time to wait out. End result was couple of knots drifting speed, direction slightly controllable with adjustments to sails and the rudder. No trouble.
__________________ All the stresses in my designs are 95% of permissible. |
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#17
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| Perm Stress, Thanks for the descriptions of your experiences. In talking about the wandering I found with the HR46, it is highly likely that the sails may indeed have not been trimmed absolutely correctly, but I am not completely convinced of that. Have you by any chance sailed any full keel examples; with which you can compare the natural tracking ability of one versus the other? |
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#18
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Full keel examples: the 8.5 m boat I mention is long keel. It is an old International Dragon class racing boat resurrected from scrap condition and converted to cruiser. ID is full keel design, dating back to 1922. Average keel chord length is about 40% of LWL. Upwind and close reaching she track better as boats with separate rudders and short keels. Downwind, however, steering is much more difficult because the rudder has so much less leverage to turn the boat. It is also more demanding physically, as you need significant force to operate the tiller. I have spent several seasons on this boat. We covered about 2000 miles each season offshore, so became to know the boat quite well. It must be noted, however, that Dragon hull form is extremely well balanced. For us it was quite normal to sail at 45 degrees of heel for days, and not feel anything wrong for it (except when cooking and eating , of course ). I also had (very limited) experience on 12m LOA yacht of L6 class (quite popular boats once in Soviet Union, designed about 1960-s, a few still sailing). She also has long keel and keel hung rudder, but is brute to handle, and not well mannered, if fast. On the other hand, I did experienced all the extremes (form "absolute concentration for every second, or you will round up" to "lash the helm and relax for an hour") on yachts with separate rudders and keels of various configurations. To sum up, I could repeat, that for easy steering it is more important to have reasonably balanced hull form, proper rig and to set appropriate sails for the conditions. The difference that I happen to notice, is that with long keel it easier to find a balance to lash the helm and enjoy, as with short keel. also the range of wind angles / strengths/ sea conditions is wider. But it should be kept in mind, that long keels and short keels usually go with hulls, designed to quite different concepts and requirements. examples like Spirit Yachts (short keel and spade rudder on classic balanced hull) http://www.spirityachts.com/ are not plentiful. So it is not correct generalize about ultimate influence of keel configuration...
__________________ All the stresses in my designs are 95% of permissible. |
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#19
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http://www.yachtlightblue.co.uk/the_boat.html |
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#20
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| Milan, Thanks for finding it. I was not succesful finding it myself. I want to examine it further and will see how much data and features I can find within the design. |
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#21
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| Perm Stress, Much thanks for going over your experiences again. I think that what you are saying is that all boats are not equal; one really needs to sail them under a variety of conditions to know them. There are so many variables. In time I will reach a point of knowing what will be the best solution/compromise. I need more sailing time in the boats that appeal to my senses and convictions: in order to judge and compare them. |
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#22
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| Boats Worth Examining IMO Cheoy Lee's LRMS 43. They actually came in two slightly different versions. The first is by Perry, the second by Seaton-Neville (or maybe Beeldsnijder) had a flybridge. You can see the different brochures here. I think they're a bit pricey and a bit too much windage. Hans Christian's 39 and 44 Pilothouses. I think they're the best looking. (Pan) Oceanic's 38, 43 & 46 (aka Seastar 46 or Mao Ta 46). Pilothouses. Spindrift 43 (aka Formosa 44, Hampton 43, & Young Sun 43) Pilothouse here & here. It seems to be the best valve although I understand the Hampton's and even Young Sun's might not have been built quite as well. |
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#23
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| TealTiger, Thanks for your efforts, some of these boats are new to examine....which is good for me...tend to get in a rut while looking. I'll go over them again to absorb their features. I like some of the advantages of a pilot house, but wonder about those large flat windows from a strength point of view. It must certainly be comfortable. Just not sure. One or more of the boats had a companionway right off to the side. I prefer it central. In some, the flatter uncluttered deck is very appealing. All food for thought. Thank you. |
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#24
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| That's a valid point. Thou it's allways possible to put smaller windows, even dead eyes, in a pilot house. Agree with the central companionway. Had dozens of sketches having them of the sides and found it needs somewhat bigger boat (than my 33') to have them properly in a safe manner.. |
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