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  #31  
Old 07-25-2009, 06:13 AM
Stumble Stumble is offline
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Xarax,

The first is the definition of a Motorsailor and no it will never be worth the added complexity since displacement hulls are very efficient movers of heavy cargo, and the reduced weight will never make up for the increased complexity. At the weight of these vessels it just isn't worth the incramental savings in fuel costs and engine size and I can't imagine it ever would

The second is expressely forbidden by every ocean racing organization, insurance carrier, and standards body for safety reasons. A boat carrying sail MUST have a tremendous amount of initial stability in any conditions, and moving balast is limited to around 20-30degrees of heel. The other problem is that moving ballast significantly reduces the ability of a vessel to be self righting in the event of a knockdown. Even more so when the moving ballast makes up a significant part of the total ballast available.
This is a very acceptable trade off for racing boats that are fully crewed, meticulously maintained, and are checking in at 4-6 hour intervals. But for a cruiser it is a system that will cause people to die. Flat out, no question at all in my mind. Just do an internet search for information on the number of Open 60's 70's ect that broach and can't right themselves. Now remember these boats have millions in maintenance budgets, the skippers are the best in the world, and they have the best weather forcasting available. But every Volvo race there is at least one of a fleet of 20 odd boats, they flips and can't right itself. Not really a good option for the long distance cruiser.

Xar the second problem with the second type of boat is that you are doing this to gain what exacally? Take the average motor yacht and put a sail on it, and it might tack through 180 degrees. Remember with no keel it will just slip through the wayer sideways. These boat also have a HUGE amount of drag compared to even a heavy displacement sailboat. The deep flat transoms, combined with normally vertical sheers practically scream inefficient hull design, but maximum internal volume under way. Even moder trawlers are normally nothing more than this design with a slightly throwback look, and little to no effort made to make them efficient underbodies.
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  #32  
Old 07-25-2009, 07:10 AM
FAST FRED FAST FRED is offline
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Location: Conn in summers , Ortona FL in winter , with big dock & room for O'nite stop .
Another hassle is most boats are small, to be affordable , so have limited interior volume.

A big water ballast moment would take up a huge amount of room.

On our 33ft we gave up loads of room to be able to have dual tankage of 6 x 35G .

Dual tankage for us means two bladders in a tank space , so we can decide which we will carry fuel, or water.

Most of our ICW Loop, Bahamas and Carib cruising , diesel is far easier to get than great water. So its usually 25Gal in the diesel day tank, and about 200G of water.

As a cruising boat that has a 40% ballast ratio, having one side full (100G) and the other empty of water only makes 2 or 3 deg of heel in a slip, so while it might make a long tack a tiny bit more comfortable , not much.

The best thing one can do for a modern motorsailor is to make the vessel a REALLY GOOD sailor.

This is easy as there are no rating rules (slowest seeming boat wins) so plenty of sail can be carried in a fine efficient rig.

Our 33ft 90/90 would probably rate as a 45 ft "racing boat" , but sail area is what gets the job done.

FF
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  #33  
Old 07-25-2009, 08:32 AM
xarax xarax is offline
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Thank you again Stumble,
Quote:
Originally Posted by Stumble View Post
The second is expressly forbidden by every ocean racing organization, insurance carrier, and standards body for safety reasons.
This is the last thing that should be considered right now, isn’t it ? Give me first a fast, safe water ballasted motorsailer and I will manage you get all the licenses of the world !
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Originally Posted by Stumble View Post
A boat carrying sail MUST have a tremendous amount of initial stability in any conditions...
Even when it is not sailing? Why ?
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Originally Posted by Stumble View Post
Remember with no keel it will just slip through the water sideways.
With no keel, but with one or more retractable centreboard, or bilgeboards, or leeboards, etc.
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Originally Posted by Stumble View Post
These boats also have a HUGE amount of drag compared to even a heavy displacement sailboat.
I do not say that the hull will remain the same as it is on these motorboats! . We need a specially designed hull, and that is the crux of the matter, I suppose.
All your points are right, but nobody ever said that any birth is an easy, secured phase in the life of any creature...It may well just drive us to the next thread, as it happens more than often ...
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  #34  
Old 07-25-2009, 08:54 AM
xarax xarax is offline
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Nice we meet again Fast Fred ! I am glad you are well and enjoy sailing everywhere.
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Originally Posted by FAST FRED View Post
A big water ballast moment would take up a huge amount of room....
As a cruising boat that has a 40% ballast ratio, having one side full (100G) and the other empty of water only makes 2 or 3 deg of heel in a slip, so while it might make a long tack a tiny bit more comfortable , not much.
I am thinking that it may be feasible to integrate quite big external sidetanks on the main hull, just above the waterline, "with their pros and cons ' , as TeddyDriver tells us, and inside " the plenty of flair to the topsides so hull beam increases markedly with heel ", as Crag Cay tells us.... But the main hull, the sidetanks and the raised deck house should all be intergraded into one round solid shape, posing minimum windage when the boat heels.
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  #35  
Old 07-25-2009, 01:25 PM
apex1
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I give up, this bloke will never understand!
Lets hope he finds a criminal to build his premature dream.

Quote:
Originally Posted by xarax View Post
This is the last thing that should be considered right now, isn’t it ? Give me first a fast, safe water ballasted motorsailer and I will manage you get all the licenses of the world !
ονείρωξη

Soon he will learn that his boat sails nowhere. And the authorities will shut his bigmouth right in the first port.

And thank you stumble, Teddy, Fred, for all the wasted effort.
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  #36  
Old 07-25-2009, 06:01 PM
apex1
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Go ahead, you´re on the right way! And good winds.
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  #37  
Old 07-25-2009, 06:39 PM
Stumble Stumble is offline
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Apex,

I am with you. He will never understand why a boat that is designed to flip over isn't a good idea in a bluewater boat.
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  #38  
Old 07-25-2009, 07:01 PM
apex1
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Apex,

I am with you. He will never understand why a boat that is designed to flip over isn't a good idea in a bluewater boat.
You´re right mate! Let him "design" that (I still wonder how) and find someone to hammer the crap together. If they let him leave the place of launch we are rid of him in the first gale.


Xarax
I agree: >>> a stupid is a stupid is a stupid.<<<
and add: and remains to be...........you have proven that.
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  #39  
Old 07-25-2009, 11:48 PM
Guest62110524 Guest62110524 is offline
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Quote:
Originally Posted by Stumble View Post
Xarax,

The first is the definition of a Motorsailor and no it will never be worth the added complexity since displacement hulls are very efficient movers of heavy cargo, and the reduced weight will never make up for the increased complexity. At the weight of these vessels it just isn't worth the incramental savings in fuel costs and engine size and I can't imagine it ever would

The second is expressely forbidden by every ocean racing organization, insurance carrier, and standards body for safety reasons. A boat carrying sail MUST have a tremendous amount of initial stability in any conditions, and moving balast is limited to around 20-30degrees of heel. The other problem is that moving ballast significantly reduces the ability of a vessel to be self righting in the event of a knockdown. Even more so when the moving ballast makes up a significant part of the total ballast available.
This is a very acceptable trade off for racing boats that are fully crewed, meticulously maintained, and are checking in at 4-6 hour intervals. But for a cruiser it is a system that will cause people to die. Flat out, no question at all in my mind. Just do an internet search for information on the number of Open 60's 70's ect that broach and can't right themselves. Now remember these boats have millions in maintenance budgets, the skippers are the best in the world, and they have the best weather forcasting available. But every Volvo race there is at least one of a fleet of 20 odd boats, they flips and can't right itself. Not really a good option for the long distance cruiser.

Xar the second problem with the second type of boat is that you are doing this to gain what exacally? Take the average motor yacht and put a sail on it, and it might tack through 180 degrees. Remember with no keel it will just slip through the wayer sideways. These boat also have a HUGE amount of drag compared to even a heavy displacement sailboat. The deep flat transoms, combined with normally vertical sheers practically scream inefficient hull design, but maximum internal volume under way. Even moder trawlers are normally nothing more than this design with a slightly throwback look, and little to no effort made to make them efficient underbodies.
well that WAS the case
but a panel of the experts, and that included all the top sailors like Isa Autissier, who is not only, a contender for the best ocean racer of either gender, but a person with Eng Degree, got together and , discussed how they could get these boats to not stay inverted, , mainly it was the broad flat deck, no shapely houses and or decks etc, It was NOT the righting arm , or the ballast ration, they just flipped and lay on the deck Even waves were not enough to turn them up
Why on earth you are ridiculing Xarex who quite obviously is an extemely intelligent person, is beyond me
You see argument, constructive is helpful Debate, without such then we become entrenched In the rut, tunnel vision
I build big strong heavily and deep[ly ballested monos, which are at same time quite light And am most certainly not oppOsed to the idea of water ballast
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  #40  
Old 07-26-2009, 12:37 AM
Guest62110524 Guest62110524 is offline
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you take my flagship
look at the shape in the house
ok some could call her a mo sailer, but at only 18.5 tonnes and that includes 1500l fuel and 7500 kg lead in scheel keel, she is a true sailing yacht
If an open 60, had a house like this, she would immediately self right
the angle of vanishing stabilty here is 138 at departure, 132 return
I guess with more beam water ballast would work But space down there is needed ---In a race boat it is not So all the wings are taken with fuel and potable water
Xarax, I can sell you one of these for um er, 1 million Euros, for less I wear myself out for Zilch!!:Or I can build you a 2 chine 40 footer, stiff as a board, a real Cape Horn boat for, , dunno

Last edited by Guest62110524 : 06-21-2010 at 05:30 AM.
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  #41  
Old 07-26-2009, 12:41 AM
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PAR PAR is offline
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The simple fact is a well designed 50/50 doesn't need water ballasting. It serves no advantage to either propulsion method. The boat will sail, power or both to it's target S/L with a minimum of fuss, if well intended. Making the power configuration lighter by a marginal amount isn't going to be significant enough to warrant the lose of internal volume, complication or contrivance.

Let's face it, the definition of a motorsailor is a craft that doesn't do either particularly well. You can arrange the yacht to advantage one propulsion form more then the other, which is often the case, but now you're paying Peter from Paul's pocket. In the end you have a displacement cruiser that motors efficiently and sails moderately well, considering it's limitations. If you want to improve it further, remove the burden of the multiple propulsion roles it must play.

In other words an efficient auxiliary will easily out sail the well burdened motorsailor, but will have motoring range limitations. Conversely, the well delivered motorsailor will have impressively long range and considerably more creature comforts aboard.

Accept the fact that an ugly, but loving wife if a much better arrangement then the beautiful, but unfaithful alternative.
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  #42  
Old 07-26-2009, 12:45 AM
Guest62110524 Guest62110524 is offline
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The simple fact is a well designed 50/50 doesn't need water ballasting. It serves no advantage to either propulsion method. The boat will sail, power or both to it's target S/L with a minimum of fuss, if well intended. Making the power configuration lighter by a marginal amount isn't going to be significant enough to warrant the lose of internal volume, complication or contrivance.

Let's face it, the definition of a motorsailor is a craft that doesn't do either particularly well. You can arrange the yacht to advantage one propulsion form more then the other, which is often the case, but now you're paying Peter from Paul's pocket. In the end you have a displacement cruiser that motors efficiently and sails moderately well, considering it's limitations. If you want to improve it further, remove the burden of the multiple propulsion roles it must play.

In other words an efficient auxiliary will easily out sail the well burdened motorsailor, but will have motoring range limitations. Conversely, the well delivered motorsailor will have impressively long range and considerably more creature comforts aboard.

Accept the fact that an ugly, but loving wife if a much better arrangement then the beautiful, but unfaithful alternative.
did you mean say 100/100? a 50 fifty is neither fish not fowl(quote some famous schooner builder down in Biloxi, when asked abt the ketch rig)
there are almost no 50/50 built these days No market, you may as well go to power
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  #43  
Old 07-26-2009, 02:37 AM
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TeddyDiver TeddyDiver is offline
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So let's take the consept seriously (atleast for moment) to see what's possible.. First, Xarax, what are the design targets etc? Bluewater motorsailor, self rightening when sailing, waterballast only, speed? load? range? else?
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  #44  
Old 07-26-2009, 02:49 AM
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Teddy
I simply get rattled talking to a faceless person, please do paste yourself here
I am dear amigos with ole Vlad Pute, and he says SHOWS YOUR FACE IN FACES TO NAMES THREAD

http://www.boatdesign.net/forums/ope...-22075-15.html
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  #45  
Old 07-26-2009, 05:10 AM
xarax xarax is offline
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Thank you Woosh,
I was thinking of a beamier hull, to make room for the sidetanks inside a substantial amount of flare, ( and possibly, just possibly, increase the stability of the boat when it heels under sails), but of a higher deck house also, to be able to right this fat lady...So there is a real danger to be trapped into a vicious circle here...a design spiral going straight down the bath tube. What is another danger is excessive windage, so I was thinking also of a shorter but quite higher raised deck house aerodynamically (teardrop?) shaped. Will such a shape work ? I have no idea.
Thank you again TeddyDriver,
The question that was posted in this thread, and it was only a question, not a project, was posted after another one about MacGregors, of which I have some experience and which I personally find very limited for a broad range of seas, including the sea I use to sail. So I have thought ; Is it possible that this craft is the end of the line, the best possible water ballasted sailing craft, or there is much more window here to exploit, and we can do better ? As an engineer, I am a one-can-do-better junkie...
So I still believe there is more room there, and a water ballasted motorsailor can be really improved, as a design concept, and may be, just may be, reach the state of development where we can consider it to be a true bluewater cruiser. I have to repeat, because some people are TOO short sighted and conservative, even for the standards of traditional sailors, that the whole idea was a highly hypothetical one, asking for patience and imagination, ( and not the unfortunate, impolite and brutal comments of apex1...)
To have a chance alongside its older cousin, the traditional keel ballasted motorsailer, I think the main ' problem" that such a craft should address, is motoring speed. If the hypothetical lighter vessel doesn’t go at least 30% faster than a same LOA traditional motorsailer, even with 60% higher fuel consumption, It will not be worth the trouble I guess. Of course, these are just numbers...
As for if this craft should be water ballasted only or not, I have also no clue...As I have said, a number of batteries put as low as possible in the hull can support some of the overall stability, while serving the pumps at the push of a button. But would we need some additional lead ballast ? I do not know. I guess that, if we can have some help of much flared topsides, there is no point of "carrying the same load twice", as with water ballasted multihulls. In case of going turtle, I think that a quite high raised deckhouse would suffice to right the vessel.
As for the load and range, even going down 30% for the load and 60% for the range, in comparison with the traditional motorsailer, will not sink the idea, I suppose. just numbers,...
Thank you again PAR,
'Accept the fact that an ugly, but loving wife if a much better arrangement then the beautiful, but unfaithful alternative.''
I have accepted it, and I suffer the consequences, fortunately or not...
And my wife will not set a foot in anything I do, wisely perhaps...But sometimes one is just getting tired of any luxury, tired of carrying loads, lead or gold...I guess that, at some point, I am getting tired to drag all this lead ballast, of riding a lead mine. And as I do not want to go to motorboats with all these people from my outer space, I am thinking of water ballasted sailing craft, which, I have to say it again, if feasible, would be MUCH different from the motorsailers you describe. Not better, not worse I hope, but much different. Just like a new wife...
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