A bluewater, ocean going water ballasted matorsailer. Why not?

Discussion in 'Motorsailers' started by xarax, Jul 23, 2009.

  1. TeddyDiver
    Joined: Dec 2007
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    TeddyDiver Gollywobbler

    To me it sounds like you are thinking a kind of motorsailor version of MacGregor (not a true bluewatercruiser) with self rightening capability and some more range??
     
  2. xarax

    xarax Previous Member

    No! If we wil not reach a point where we have a true bluewater cruiser, the whole thing will be only a hole in the water...I simply say that some of the numbers of a heavy ocean going motorsailer should be sacrified a little ( I gave some vague estimations ) if we want to reduce the lead ballast as far as we can, while motoring ( with a greater speed ), and use form stability and water ballast instead, as far as we can, while sailing.
    May be I should have used an altogether new name, like sailing motorboat, for example, because I suspect names tend to stick on peoples mind and drive to preexisting, wrong images...
     
  3. apex1

    apex1 Guest

    As I said............ he is´nt willing (a necessary prerequisite for being able) to learn...............
    But thats not important.
     
  4. mydauphin
    Joined: Apr 2007
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    mydauphin Senior Member

    Remember water in water does not weight anything. The amount is displaces is what it weights. It offers trimming advantages and adding weight to boat in general but because the weight of water is what it displaces you can't move weight below to act as leverage. On reverse of idea, a deep empty keel would provide positive flotation in the wrong place.
     
  5. Stumble
    Joined: Oct 2008
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    Stumble Senior Member

    Bit of an asside,

    But no I didn't save up a 100 coke bottles to get my captains license. I spent ten years living on a sailboat in the carribean, then worked on commercial vessels for three. Then took a three week course at Houston Marine before taking and passing my 100 Tonn Masters exam.

    For my Law license, I went to one of the best law schools in the country, to get my Juris Docterate, then passed the Louisiana Bar Exam.

    If you don't like my responce to your questions, tough. Grow up and accept that you might, just might, be wrong.
     
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  6. Guest62110524

    Guest62110524 Previous Member

    I am always puzzed as to why sailing boat skippers and power boat skippers, call themselves captains, It is , I think a USA thing
    IN uk EVEN skippers of 2000 tonne trawlers would not do so neither would the man in charge of a pretty large tug♦boat
    Stumble, all you have to do now is post your pic , in the thread faces to names
    Lawyer jokes could start from here The world needs em like we need criminals, they are surely wrecking this country with their ambulance chasing, their class actions, their quest for money
    However you may be in the minority, I hope so
    As for your degree, fine , but I think Xarex has several of them
    is multilingual, and that includes methinks Latin, which is so much part of the law still in Europe at least And you probably chased him away
     
  7. xarax

    xarax Previous Member

    I am probably, most probably, wrong, as I were many times in my grown up life, and I wish I will be wrong many times more ( because that will mean I will live more...:)).
    But I think it was obvious from my posts that, although I hope that there is a window there, I am affraid that perhaps it is tightly closed, ( just like so many others...), and I would not be able to open it up...I repeat, this is not a project, this is an invitation to answer a (still open, at least for me ) question.
     
  8. mydauphin
    Joined: Apr 2007
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    mydauphin Senior Member

    Life and especially engineering is about compromises.
    You can make something fast, fuel efficient but then it won't be cheap, etc...
    You usually get two out of three, same with women.

    You want light, heavy and flexible. Water ballast is not the best ballast, because the density or weight is the same as water. And when you remove it, it make boat lighter but in wrong place...

    You don't need a degrees, colleges, societies, lawyers or engineers to understand these facts. The MacGregor 26, which is a great little coastal boat, but it does not rely on water ballast only, it has retractable keels I believe.

    So everyone play nice...
     
  9. xarax

    xarax Previous Member

    I agree..,.:)
    But I had never say that it will be cheap, had I ? I think that, if it will be about 30%-50% ( only...) more expensive than a traditional motorsailer, the other two main advantages, speed while motoring and shallow draft, will worth the trouble. People are paying ridiculous amount of money for bluewater motorboats, why not for a craft like that?
    I think that there is a misunderstanding here...We should not confuse the sidetanks, which serve for added stability while sailing, with the self righting system . There are many types of self righting systems, but the simpler is this: When the boat is gone turtle, water ballast from tanks in the lower part of its hull is released, through a systems of valves and pipes, to one of the two sidetanks. With the additional help of the raised deck flotation, the boat rights itself. So there is never any moment when "the boat is lighter in the wrong places..."'Now, one can use the same or other sidetanks as flotation devices and/or additional water filled tanks to increase the righting moment on the rig, but this is on top of the main self righting system, which must always be at hand when the boat is travelling under sails.
    Easier said than done ! And I am by no means an expert on self righting systems...or any systems whatsoever...:) . AND there are, of course, the additional problems of rig weight, of sail and centerboard substantial drag in the phase of righting which should be as short as possible, etc...I never said it was going to be an easy, or an assured feasible task after all, did I ?
     
  10. M-Sasha

    M-Sasha Guest

    They will not serve that way, just for added weight and complexity! A good hull design serves primarily for what you need in a motorsailor. What you are so stubbornly trying to achieve is to solve a non existing problem!
    The experts have told you that in several friendly (and some frank) posts already. Why do´nt you believe their expertise? PAR brought it to the point in his first post.

    Sasha
     
  11. mydauphin
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    mydauphin Senior Member

    Xarax,
    I have huge water tanks on bottom for 3/4 of my 72' hull. I used them to trim boat front and back. I also never run out of water. In canals and swallow areas as you say I can raise or lower boat bout 6 inches in front or back or 4" throught out. I can make boat lighter or heavier. I like it. But it is way too slow and not heavy enough to act the way your talking about. I was at one point thinking of using tanks for side to side stabilization. But ones again water is not heavy enough unless you move alot very quickly, and this can be dangerous if it goes the wrong way. By the way, I don't need righting tanks... The boat is design to flip around with or without water.
     
  12. xarax

    xarax Previous Member

    If we design them to be functional and serve that way, they will be functional and serve that way! And they will be much much lighter than the lead or iron ball tied at the foot of your old grandmatorsailer.
    Your grandmatorsailer does not have any other problems indeed, because it has one that is big enough! :) It is a slow, old lady with an iron ball tied to her foot, that nobody, (ok, almost nobody), wants any more. How many motorsailers are sold worldwide, and how many bluewater motorboats, passage makers, trawlers, etc? The grandmatorsailer you are talking about is a thing of the past. She was born in the short historic interval when the old, sailing boats were leaving and new, motorboats were coming...Now we are in the next epoch, we could not possibly have preserved your old grandma alive and well even if we would have been the best experts of geriatric medicine. I say that one can return from motorboats to sailing boats again, but this time the young lady will be DIFFERENT.
    Expertise is fine in the bubble boom and not so fine in the recession...Your old grandmatorsailer is a lady born before the1929 recession, do you really think that the experts are going to prolong her life after the 2008 recession? I don’t think so... :)
    I am deliberately crude, of course...I love old motorsailers, as I love my old Roleiflex ...but I must confess that I am shooting photos with a Olympus 26x SP-590UZ ultra zoom (26X optical zoom), that is not even a DSRL! It is a '' bridge camera'', like the motor-sailor bridge , the water ballasted sailing motorboatis I stubbornly still think it is not only a figment of my imagination that needs expert/ proffesional help.
     
  13. xarax

    xarax Previous Member

    Thank you mydauphin,
    72 feet ? Veeery big... I don’t know if, and how, self righting systems are scaling up...We only know the smaller British lifeboats and the 47 ft US MLB, they are fast and capable of self righting in less than 30 seconds, usually 15. Your boat is slow because its hull is a classic heavy displacement hull. If you look at the bottom of these lifeboats while they make their self-righting tests, you will see that they have extended flat sections and hard chines. With such a hull, you do need a high raised deck house AND a self righting system (based upon the release of water ballast from high to side tanks). Form stability by itsself is not enough. Nowadays one can have computerized, electronically controlled valves that do not make mistakes...You would not possibly put yourself in a greater danger I guess than the danger of a whale reducing the draft of your keel...
    If you had a flatter hull, and you could trim the weight of the boat front and back, you could possibly find the optimum angle of incidence for each loading and sea conditions and reduce drag.
     
  14. White Wolf
    Joined: Jul 2009
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    White Wolf Junior Member

    An alternative motorsailor

    I had a look at this boat in New Zealand last year. Visit www.powersail.co.nz.

    Essentially a water ballasted( albeit additional ballast) 50ft yacht that will do 18kn under power or sail given the right conditions. It swings a 36 inch prop off 450 hp and retracts the entire drive assembly into the hull to reduce drag under sail. Twin rudders toe out marginally under sail to lift the stern and overcome traditional speed length formulae as it is essentially planing.

    Water ballast is pumped from side to side for sailing and ejected for motoring.

    Now that's motorsailing!!
     

  15. PAR
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    PAR Yacht Designer/Builder

    Xarax, you really don't get it do you. There are some truly fine motorsailors available, most will exceed you expectations without water ballast. I have a friend with a 65 sailing yacht that powers at 18 knots and can top 20 in the right conditions with just over 100 HP, so frankly you're just typing for entertainment value. There are many well executed customs and semi customs out there. Maybe you'd be better off talking to a local NA and get a clue about what is available, because frankly your arguments thus far have little merit. I would think this more fruitful then attempting to dissuade professionals and semi professionals within the industry, to your little understanding of the dynamics in your concepts.
     
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