My 52m raised deck sloop, question of windage on superstructure.

Discussion in 'Boat Design' started by rlackey, Feb 11, 2010.

  1. apex1

    apex1 Guest

    Go here:

    http://www.dianayachtdesign.com/yachts/historical/diana249/

    and bring the proportions in relation to your (interesting) vessel, than find a comproise between the Savarona and the Colombaio Sun.

    [​IMG]

    imho the best shaped motorsailor of all times and sizes.

    Nothing is impossible...........

    ......and much not sensible too...

    ..but boatbuilding is compromise, go for it.

    Regards
    Richard
     
  2. Tad
    Joined: Mar 2002
    Posts: 2,303
    Likes: 184, Points: 73, Legacy Rep: 2281
    Location: Flattop Islands

    Tad Boat Designer

    Generally speaking modern motoryachts totally lack elegance. This is were I ended up trying to re-interpret the classic two funnel motoryacht. This 165' model was done a few years back for a Chinese spec builder...on reflection they thought better of the idea....which was smart. Now I would make the funnels less classic, more modern. The idea was that they would be functional, hiding electronic antennas and providing a private lookout....

    bowprofile2.jpg

    sternprofile3.jpg
     
  3. rlackey
    Joined: Jun 2005
    Posts: 49
    Likes: 1, Points: 0, Legacy Rep: 19
    Location: Cape Town, South Africa

    rlackey Junior Member

    I've been working on a few other possible arrangements. It seems one of my best options is to retain my overall deck layout as is but increase LOA to 104m (341ft) and rig her as a three mast schooner. This puts her closer to the Savarona in size, also take a look at the 90m 'Athena'. It brings her profile and resulting windage overall far lower in relation to the sail area she will carry.

    This is all well and good for fun but probably places her far out of the realms of possibly ever being built.

    My guess is she'd be about 1600 tonnes at 104 meters and if built from aluminum as I'd intended, she's probably be the worlds largest aluminum sailing yacht... I am happy to be corrected. Steel might be more practical and economical at this size in this economy.

    Ok, so if I go that route this is going to be a learning exercise but should be lots of fun. Hope some of you will stay for the ride and help me where I need it!
     
  4. rlackey
    Joined: Jun 2005
    Posts: 49
    Likes: 1, Points: 0, Legacy Rep: 19
    Location: Cape Town, South Africa

    rlackey Junior Member

    Wow, she's also beautiful and smaller than my originally intended 52m but looks very similar to what I want to achieve, of course I like my raised deck hull. Maybe as you say, some compromise between this and something larger is where the sweet spot is.

    Maybe I don't need to double to 104m though, that's perhaps a bit extreme.
     
  5. rlackey
    Joined: Jun 2005
    Posts: 49
    Likes: 1, Points: 0, Legacy Rep: 19
    Location: Cape Town, South Africa

    rlackey Junior Member

    http://www.savaronavoyage.com/mainpage.html

    Savarona though is something else... wow! Talk about space! She's huge!

    So Diana's Mata Mua is 38.5m, I'm currently at 52m and Savarona is 136m but for all intents and purposes I consider Savarona a ship.

    So I've got some goal posts on two extremes and need to find my balance somewhere in between. I've been playing around at 104m, double my current 52m and proportions look very good, she looks beautiful at that size, elegant and well laid out with more than enough space for some interesting design and interior layout possibilities.

    Her profile with the raised deck fore, and decks above as is, takes to a three mast schooner rig nicely... she looks balanced. It also increases the height of the lower deck (below the raised portion) higher above the water, much better when I move the hull into a heeled position.

    She'd probably sail well too, but it's just so big!
     
  6. rlackey
    Joined: Jun 2005
    Posts: 49
    Likes: 1, Points: 0, Legacy Rep: 19
    Location: Cape Town, South Africa

    rlackey Junior Member

    Check out "Mekong" from Cox & King...

    http://www.francoisgrosjean.ch/cox_and_king/catalogue_8.html

    She's 240ft but a steam-yacht, not a sailing yacht as I would like. Still, nice proportions and I could imagine her with a full set of sails instead of the funnel.

    I'll get there... just need to find that sweet spot where it all comes together.

    At these sizes, I should probably design for steel not aluminum? Thoughts?
     
  7. rlackey
    Joined: Jun 2005
    Posts: 49
    Likes: 1, Points: 0, Legacy Rep: 19
    Location: Cape Town, South Africa

    rlackey Junior Member

    "Athena", another reference I can use.

    http://www.charterworld.com/index.html?sub=yacht-charter&charter=athena-1916

    I'm going to take the work I've done to date for the 52m, and the preliminary calculations I've done at 104m, pull together as much research as I can on the Savarona, Mata Mua, Athena and even the older Cox & King steam-yachts and hit the drawing board fresh.

    I'd quite like to work on a series, perhaps use my existing 52m hull (which has been hundreds of hours of work) and finish the 52m I started but without all the built up superstructure above deck in order to keep the profile and windage down, and then also work on a 77m and the 104m as well.

    I will probably be quiet again on this forum for a couple months while I get working on lines, stability and hydrostatics at 77m and 104m. Once I've got my hull and superstructure nailed down on all three in the series, I'll share them with you all.

    Thanks for the help and encouragement.
     
  8. rlackey
    Joined: Jun 2005
    Posts: 49
    Likes: 1, Points: 0, Legacy Rep: 19
    Location: Cape Town, South Africa

    rlackey Junior Member

    I just looked up some history of William Francis Gibbs, architect of Savarona, and he was self-taught, like me... that's made my day!
     
  9. rlackey
    Joined: Jun 2005
    Posts: 49
    Likes: 1, Points: 0, Legacy Rep: 19
    Location: Cape Town, South Africa

    rlackey Junior Member

    Fifty Two... my 52m raised deck sloop continued...

    Hi Guys,

    I'm back again... first time since Sept 2010. It's been more than 5 yrs since I started this design.

    Here's progress. See attachments.

    Hullform is done now, hydrostatics check out perfectly, superstructure decided upon as shown so lots of the hardest work is done. Getting there.

    Thanks,

    Rich
     

    Attached Files:


  10. Perm Stress
    Joined: Sep 2009
    Posts: 554
    Likes: 23, Points: 0, Legacy Rep: 323
    Location: Lithuania

    Perm Stress Senior Member

    Why so bluff stem? It will push quite a hill of water before it.
     
Loading...
Forum posts represent the experience, opinion, and view of individual users. Boat Design Net does not necessarily endorse nor share the view of each individual post.
When making potentially dangerous or financial decisions, always employ and consult appropriate professionals. Your circumstances or experience may be different.