Conser 47' Narrow hulls & Low freeboard

Discussion in 'Boat Design' started by Bazcatana, Aug 12, 2012.

  1. Bazcatana
    Joined: Aug 2012
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    Bazcatana New Member

    I need help understanding the design concept of the Conser 47' Cat.

    The Bows look to be about 36 to 42" from waterline to deck which is low by comparison to high free-board Cats - is this a big problem???

    Very narrow Transoms and narrow hulls, Bows as above and light weight plus lots of sail area giving it a 'Bruce number' of 1.47 (power to weight ratio) which is high - will the Bows nose dive due to the low free-board ??????

    Designers please comment - my thoughts are that 42" bow height is too low and will nose dive a lot, slowing the boat down as she dives into waves on a beat to windward.

    Comments please, not just chit chat, hard facts prefurred.

    Regards

    Barry Parkinson
    Photos from me if you Email bazcatana@yahoo.co.uk
     
  2. brian eiland
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    brian eiland Senior Member

  3. Bazcatana
    Joined: Aug 2012
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    Bazcatana New Member

    Conser 47'

    Hi brian eiland,

    When you get round to replying to my questions about the Conser 47' :-

    1) Low Bow height of 3' approx & narrow entry.
    2) Hulls - 3' approx at waterline around Skeggs area.
    3) 12" wide Transoms
    4) Quite low Bridge-deck clearance.

    Four things against it being quick even though it has a Bruce number of 1.48 (power to weight ratio).
    Two things for it, Rotating Mast and Light weight.

    I raced a Voyager 43' down in Georgetown Exuma this year that was almost the same as the Conser47' except for a fixed mast, that had a high Bruce number as well BUT, it could not beat to windward in 20/25 knots due to the waves slamming into it stopping it powering forward due to Low bow height, low Bridge-deck clearance and Skeggs, she sailed sideways and came 6th not First as predicted by me.

    So now we look to buy the Conser 47' that has just completed a Circumnavigation, must have done all right to get round but, alright is not a word I allow into my sailing requirements.

    My spreadsheet I developed that tells me she is fast 1.48 Bruce does not consider Bow nose diving, low Bridge-deck clearance but does include Water line length to width ratio which is very good, it's the unknown nose dive, does it do it with narrow Transoms or does it balance out instead of nose diving???

    24" Bridge-deck clearance is low, my Catana 381 has 2' 6" or more so no slamming there but, what about the Conser 47'??????

    I have search high and low for data, I have watched Videos of the boat in high wind, no problem just spray off the Bow, I have every photograph of 6 Conser 47' boats, nothing there, no Blogs only the comment that the Blue one Cart-wheeled with 12 people on board in a 30 knot gust - 20 to 50 knots in one big hit and over she went.

    I'm Ex Tornado Olympic so I can tame Cats in a blow, that's not the point, I think the Conser 47' will nose dive in a blow and in waves, not sure if the Wave pearsing Bows will just cut through the waves while the narrow Transoms will sit down allowing the Bows to stay up.

    Any thoughts from any Conser 47' owners out there or David Pollitt and John Conser come back.

    Regards

    Barry Parkinson
     
  4. Chuck Losness
    Joined: Apr 2008
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    Chuck Losness Senior Member

    I know John back from the days when he and his wife ran Windward Sails in California. I sailed more than a few miles with John. I believe that they still live in Newport Beach, California. John's wife Gerry ran a boat photo business for years. I don't have contact information but you should still be able to track them down. I don't know how much help John can give you. He fell off one of the 47's he was building and suffered massive head injuries. He has never fully recovered. I last saw him after an Ensenada race about 10 years or so ago. He was there with Gerry who was selling photo's of boats from the race. I have never sailed on a Conser 47 so can't give you any feedback. Only a couple were built to my knowledge and none after John suffered his accident. Hope somebody can help you out.
     
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  5. brian eiland
    Joined: Jun 2002
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    brian eiland Senior Member

    Hi Barry,
    I think you have done a very good analysis of this vessel design yourself. It has long thin hulls for performance purposes, and those narrow transoms are there to help keep her bows from being overpowered. Of course we've learned over the years its not so much these broad sterns that push the bows down, but rather the tall sail plans themselves.

    John Conser (great guy) showed up at the Annapolis boat show with his 47' design s year or so after I brough the original 37' Louisiane into the USA. I always kidded him that he just wanted to build a larger Louisiane....after all we already competed with his 27' Warrior cat design and the 27' Stiletto we were representing :) .

    You have to remember in those days (1986-87) there were very few choices in larger 'production' multihulls....mostly the British Prouts, Catalacs, Catfisher, etc both john and I thought these 'stoddy old designs' were part of the problem in getting the mostly monohull world to give a look at multihulls. We needed something sleeker, less boxy, lower windage, more sail area, more performance.

    John developed the 47, I picked out the F/P Louisiane 37 from France. Both of these designs are really more of a 'coastwise' type rather than open ocean. In order to keep that low profile, sleek look they were designed with low bridgedeck clearances,...certainly too low for open ocean use,...and too 'slender' to carry cruising loads. (BTW I do assume you are seeking some 'cruising attributes' in this new vessel you are considering?)

    Unfortunately I never did get a chance to sail a Conser 47', so I am not a source of 'first hand onboard experience'. I did get a fair amount of time on the Louisiane I brought into the country....somewhat similar hull shape, but much less taller rig in comparison. One incident I might relay; I had a big light-air asymmetrical reacher built for her, and on one occasion when returning from the big Governor's Cup race down the Chesapeake Bay, we had some BIG gusty weather coming upon us from the stern. It was bright daylight conditions so we could observe how this rapid moving weather played havoc with the many monohulls that followed us, many of them flying their chutes. Peter Wormwood and myself made the calculated decision to leave that big reacher sail up and just square it off to the stern wind. WOW, what a ride. It literally felt as though the boat levitated out of the water by a half a foot or more and took off up the bay. (I've offered this real time experience to a few naysayers that claim that spinnakers and headsails can ONLY result in the bows being driven downward).

    Peter Wormwood was the designer of the Stiletto 30 catamarans. The second one built after the first production prototype was a custom one called Mirage. She carried a taller performance rig designed special for a client in New York. The 30 was lenghtened 27 hulls, spread farther abeam, and with blister cabins extending to the inboard sides. Thus she was a little bit heavier than the 27, but with the same slender hulls and low freeboard. I raced on her on several occasions, and she was a treat to sail. If I remember correctly there were several other of these hi-perf 30's built and raced at the Stiletto Nationals down in Sarasota. FL. I don't recall any pitchpoles....maybe a couple of bow stuffings and a couple of overturnings in gusty bigger winds during all out racing.

    Back to the Conser 47'. I look at these two quotes by you;
    1) "I'm Ex Tornado Olympic so I can tame Cats in a blow..."
    2) "...alright is not a word I allow into my sailing requirements."

    I would think the Conser is a good choice for you.

    But if your interest is to take it offshore on some cruising expeditions, I don't think it will handle the extra loading that well. For cruising performance I might make two other suggestions for you...but they are both larger boats:
    1) Indigo--a beautiful 65 footer designed by Peter Wormwood for the original owner of the Mirage 30 footer
    http://runningtideyachts.com/design-references/design-references-1.php

    2) Wild Vanilla--the original Dudley Dix 55 footer was built pretty light by a gentleman (for his own use) who manages a lot of the Gunboat production cats She is pretty lt-weight, and as yet not over loaded. I think she would give surprising performance even with her relatively fat hulls and transoms.
    http://www.dixdesign.com/55cat.htm

    more IMAGES of DH-550

    ...and a few shots of Stiletto 30, Mirage
     

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  6. brian eiland
    Joined: Jun 2002
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    brian eiland Senior Member


  7. brian eiland
    Joined: Jun 2002
    Posts: 4,964
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    Location: St Augustine Fl, Thailand

    brian eiland Senior Member

    I was looking thru some old files of mine and doing a little scanning. I found this two kit related dwgs you might not have had.
     

    Attached Files:

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