Sea Cart 26

Discussion in 'Multihulls' started by Doug Lord, Oct 27, 2010.

  1. Doug Lord
    Joined: May 2009
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    Location: Cocoa, Florida

    Doug Lord Flight Ready

    Fascinating new addition to the Sea Cart(by Oceanlake Marine in Sweden) line:

    http://seacart26.com/specifications/

    SeaCart 26 OD Specifications
    Length incl. rudder 7.92 m / 26’
    Beam 5.60 m / 18’4”
    Beam Folded 2.33 m / 7’8”
    Draft C/board down 1.49 m / 4’11”
    Weight Empty less than 700 kg / <1543 lb
    Mast Length 11.9 m / 39’1”
    Design Marc Lombard
    Builder Composite Marine Int.
    One Design Sails:
    Mainsail Area 26.6 m2 / 286 sq ft
    Jib Area 11.2 m2 / 121 sq ft
    Gennaker Area 43.8 m2 / 471 sq ft
    ============================

    Optional Curved Foils
    All SeaCart 26 OD floats have a case built in for optional curved foils. Blind cases that are finished flush to the underside of the float shape are standard equipment. The additional curved foils will boost speed above 12–16 knots of True Wind Speed (TWS) and work as a safety feature when extra lift is required to help prevent the bow from diving. They will also reduce the amount of pitching in choppy seas when sailing upwind. These features help make the SeaCart 26 behave like a larger boat. The curved foils may be integrated in the One Design rule, depending on sale. Learn more under the One Design Rule Notes section to the right.

    -------

    "Why a Trimaran?"(from Sea Cart 26 promo material)

    "The answer is easy, the first and foremost reason is performance! On any type of sailing boat power-to-weight ratio and wetted surface area are critically important performance factors. These are what make multihulls such efficient sailing craft. The wide beam a trimaran is able to have gives it exceptional righting moment. When the main hull begins to fly only one narrow hull is left slicing through the water. In short, greater righting moment provides more power and less wetted surface reduces drag, these combined equal exhilerating speed!"

    ---

    click on the top left and right images. The top right image,from SA, is with a wing rig. Note insignia on all three images showing a canting rig:
     

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  2. idkfa
    Joined: Sep 2005
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    Location: Windward islands, Caribbean

    idkfa Senior Member

    Any info on a righting system? If you fly the main hull you'll need one, no matter how flat the conditions or expert you are. A water activated float extending out of the mast, then climbing out on the centreboard?
     
  3. Doug Lord
    Joined: May 2009
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    Location: Cocoa, Florida

    Doug Lord Flight Ready

    Flying the main hull is key to real speed on a tri-I'll write them and ask about
    a righting system when I can. Good question- particularly on a sport tri like this.
    ------
    UPDATE: I've written to Tim at Oceanlake. Interesting experience. I couldn't understand why the e-mail wouldn't go thru and it turns out the the e-mail link on the Oceanlake website is misspelled!-the misspelling is on the address that comes up on the e-mail itself when you click on the correctly spelled e-mail link on their site-weird. I asked Tim to join this thread and I asked about a righting system for the 26. We'll see....
     
  4. Munter
    Joined: Jul 2007
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    Location: Australia

    Munter Amateur

    Doug - do you just read what is on SailingAnarchy and then copy paste it here in boatdesign?
     
  5. Doug Lord
    Joined: May 2009
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    Location: Cocoa, Florida

    Doug Lord Flight Ready

    ===============
    No, unless it's relevant. I've been looking forward to this boat for a long time
     
  6. Munter
    Joined: Jul 2007
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    Location: Australia

    Munter Amateur

    It just seems like the vast majority of your content is directly ripped from SA.
     
  7. Doug Lord
    Joined: May 2009
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    Location: Cocoa, Florida

    Doug Lord Flight Ready

    ===============
    That, like so much of your commentary, is just flat false. Hell, it was me that told Scott about Mirabaud!
    When SA has stuff that is relevant to something that interests me I quote them and give them full credit-as I have for years and years.
     
  8. Doug Lord
    Joined: May 2009
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    Location: Cocoa, Florida

    Doug Lord Flight Ready

    ==================

    Here is an answer from Tim at Sea Cart:

    Hi Doug

    Thanks for getting in touch and identifing the email link errors, which have been corrected.

    In regard to a righting system, our thoughts are that if you add an airbag you need to build a heavier mast to avoid it breaking if the airbag is deployed. A heavy mast with added weight (airbag) in the top is counter productive in preventing a capsize. Additionally, an airbag fitted to the end of the mast is also unlikely to aid righting the boat like a beach cat.

    Instead, from experience with the SeaCart 30 we have learnt that it's beneficial to have a mast that is strong enough to survive a capsize in most cases (SC30 - 4 capsizes, 0 breakages) and eliminate additional weight in the rig.

    The SC30's have been righted from 'turtled' by being towed bow-over-transom into the wind by a bridle attached to the front beam either side of the main hull. For the SC30 it has taken a powerful RIB with around 300HP, for the SC26 it should require less.

    As part of our sea trials of the first SC26 we may 'crash test' it to confirm our philosophy.

    Best regards
    Tim

    Tim Shuwalow
    International Sales Manager
     
  9. aussiebushman
    Joined: Oct 2009
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    Location: Taralga NSW

    aussiebushman Innovator

    Whoever this "Munter" is, he needs to be banned from this forum. His self-importance outweighs his intellect by a considerable margin
     
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  10. basil
    Joined: Apr 2005
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    Location: aUSTRALIA

    basil Senior Member

    G'day Aussiebushman,

    I think Munter is having a go at Doug Lord. Please correct me if I'm wrong but I have a feeling I read somewhere that Doug was not banned from SA forums?

    Apologies in advance if this assumption is out of line.

    Tony
     
  11. basil
    Joined: Apr 2005
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    Location: aUSTRALIA

    basil Senior Member

    Drop the word "not" from last post
    T
     
  12. aussiebushman
    Joined: Oct 2009
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    Location: Taralga NSW

    aussiebushman Innovator

    Yes, Munter was not happy with Doug Lord and actually sent me a private message "sort-of" saying he should not have said what he did.

    I am neither defending nor critiizing Doug's ideas but I can't help giving types like Munter a serve, because I have had my share of being rubbished on these forums for suggesting something innovative, or sometimes being plain wrong. How else do we make progress and learn from others if we cannot tolerate new ideas, regardless of their validity?

    Alan
     
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  13. Munter
    Joined: Jul 2007
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    Location: Australia

    Munter Amateur

    The posts above were a reaction to Doug's repeated copy/paste of content out of sailing anarchy into boatdesign. I find it really annoying but I realise it isn't against the rules of the forum and its a free world so he can do what he likes (he even copied one of my SA threads across so I didn't feel left out!). I think threads where the whole content is just post after post of text copied from another forum (like the wing technology thread) are pointless and should be discouraged but others may feel differently and I should respect that.
    Anyway - my posts above are also pointless and petty and I now recognise them as poor form. As the bushman above notes, I wrote and made that comment to him. Apparently it was not perceived as being as genuine as I meant it to be and perhaps this more public text will clarify that.

    On the other hand, I do object to your comments characterising me as a rubbisher of innovation and new ideas. I think hydrofoils are fantastic and I strongly encourage new ideas. I do also have a strong preference for rational design over fantasy.
    It is true that I have often challenged Doug's designs on this forum and have consistently found that he cannot substantiate the claims that accompany his designs. The challenges relate to real issues that he overlooks like mass, complexity, leeway and structural integrity. In response he generalises, obfuscates with reams of coloured text as some sort of justification to support his statements but provides evidence of actually considering concerns raised with his designs. He often rejects deficiencies identified by others with accusations of failure to comprehend his innovation.

    Would it be better to sit quietly and let the false promises sit as though they were real? If there were any chance of him actually building the craft I believe he would discover these deficiencies are real and would likely result in performance not matching his expectations. A real designer would make a genuine assessment of the validity of new ideas instead of the design charade that we consistently see here. Moving forward is about sorting the wheat from the chaff and if nobody identifies the chaff then how will we progress?
     
  14. Doug Lord
    Joined: May 2009
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    Location: Cocoa, Florida

    Doug Lord Flight Ready

    =======================
    This is disingenuous hogwash. When you started asking questions on the thread previous to the MPX-11 thread I answered each of your questions specifically and in detail. I soon became aware that you were not reading the material and were, instead just repeating the questions in a nonsensical obstructionist manner. That is why I do not-and will not- respond to your obnoxious comments any further. It is 100% clear to me that either you do not understand the material or are deliberately mischaracterizing and misrepresenting what I have written or both.
    More nonsense: boat designers deal with weight and the effects of gravity-not mass!
     

  15. cardsinplay
    Joined: Oct 2010
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    Location: Camp Plasma

    cardsinplay da Vinci Group

    I agree up front that this is off-topic for this thread, but since the door to the MPX-11 thread has been opened by Doug, it is appropriate to offer a response in this fashion.

    I wonder, Doug, when you accuse Munter of not reading the material you so laboriously provided on that design, if you had any idea that you would be forced to seriously back-track when you discovered that an integral element of the design (the planing ama surface) would be so grossly undersized for the job it was being called-upon to perform?

    It would seem that you have not read your own material if you are capable of making such a huge error in that singular element of the design. Naturally, this now brings even more light to the powerful questions asked by Munter which you did skip past in an effort to avoid having to address them. I read all of the material and I know where you'd like to take this design of yours. I would have liked to see it work, but I also find that it is excessively complex, to the point where pure complexity is now driving the design, rather than the search for an elegant, properly engineered solution. This gross error with the ama sizing example, is likely but one area where design shortcuts were taken in favor of adding yet another snappy bit of complexity.

    It would seem that Munter had it right from the start and that the MPX-11 is fraught with hastily drawn conclusions based on what are now likely, other hastily drawn conclusions; a veritable house of cards posing as good design work, if you will. Munter has told you that he is an engineer by training and you are making huge errors of engineering calculation. It would seem prudent to listen, rather than attack the guy.

    I would suggest that you go back to square-one, re-think the design and function of the entire boat, do your sums accurately and make your own personal discoveries based on the real workability of the design, rather than what you'd like to think might work.
     
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