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05-16-2011, 06:18 PM
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#1
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Lieutenant
Join Date: Apr 2009
Posts: 86
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Hi Folks,
Me again with another question! I have been amusing myself by looking at boats (who doesn’t, eh?) and I have noticed that there really seems to be a predilection towards less overhang on both fore and aft. Now, I just talked to one of the lads in the office who is a marine architect and we had a long talk about overhang. Personally, I think that older boats, ones with lots of overhang, look a heck of a lot nicer. He seemed to be of the opinion that this was one of the main reasons for overhang: it was a question of style. I pointed out that a heeling boat with overhang will get some more wet area, and hence speed. He admitted that was true, but only to a degree. And though they handled better in lighter winds, older boats were slower. He also pointed out that “back in the day” they needed more deck space for the rigging and prior to the advent of modern shrouds they needed the additional length.
My understanding is that with modern textiles, the need for overhang is less. The only reason for overhang on a blue-water boat would be that in heavy weather, a wave hitting said boat would actually provide additional lift to the hull, keeping it from submerging.
I guess what my question is after all that, other than they look prettier can folks see any reason for having overhang?
Thanks for your time (to read this obnoxiously long post)!
Kevin
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Kevin Barr
Ottawa, Canada
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05-16-2011, 11:35 PM
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#2
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Rear Admiral
Join Date: Aug 2010
Posts: 218
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Gooday 'Canuck' It'll be very interesting to see just how much we all learn about this overall subject by the time you get many more answers. 'Fools rush in' etc etc, so I'll be foolish & jump in at the start. The old 'racing' rules, - the 'RORC' measurement system favoured longer overhangs. That's a whole subject all in itself - several books long. Longer overhangs do make for more 'sea-kindly' motion for sure. Lighter (as in more modern designs, 'space-age' materials used in hulls, rigging & sails & a newer 'rating-rule') are not always comfortable nor do they go as fast as some people would like to make out. Hot-rods are just that - not very comfortable. 99% of all quality cruising yachts are not 'space-age' light-weight race or ex-race toys & for many good reasons other than cost. A good example would be the yacht designed by Olin Stevens of Sparkman & Stephens to the 'IOR' rule change in 1967 - - the S & S 34, designed in 1968 is a very high ballast ratio - moderate overhang - pleasant looking - world class yacht - designed to race. It is also a VERY comfortable, safe & swift, sure footed cruising vessel. In extremely light winds, ie 2 to 8 kts. an S&S 34 is almost unbeatable. The yacht has won more races around the world & done more round-the-world sailing that any other yacht design in history. A tad short on room however there are several bigger yachts by the same design team although not quite as good sailing but still well above the bench-mark. Your 'young marine architect' needs to do some serious home-work as his observations are rather fanciful & not related to the facts. Suggest he do a lot more study before he designs any meaningful ocean going vessels. Great subject & thanks so much for bringing it up. No subject - in these 'forums' is - obnoxious - if we all learn from the following discussion - as long as it's not rude or to confrontational. IMHO Kevin - you might 'google' - Sparkman & Stephens - as the associated sites are an endless fund of valuable information & knowledge. To everyone, enjoy what you do & fine cruising to you all. Ciao, james
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05-17-2011, 01:40 PM
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#3
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Rear Admiral
Join Date: Feb 2006
Posts: 437
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As with lovers... one's beauty is another's beast.
I believe that while large overhangs give a yacht a graceful, classic beauty - I think it also makes for wasted space and larger-than-necessary added expense with little gain. Marinas, boat yards and tax collectors charge by the foot now a days and if I'm going to have a 40 ft boat I'd like to be able to get the most usable space I can with it. The last thing I'd want is to be paying for a little boat with a lot of bow sprit and long boom doubling the length of the hull!
All I can say is follow Silver Raven's suggestion and shop for a well known and popular design, because:
1 - by being popular there will be lots to choose from and
2 - you'll have less trouble selling it when the time comes.
And I certainly agree with his opinion of the Sparkman & Stephens designs because I now own a 21 year old S&S designed Hylas and I enjoy a great ride and a constant flow of nice complements wherever we sail. I LOVE my boat, they're still in production, there's a long waiting list for new ones and I know I'll have little trouble selling her... therefore I have no hesitation about upgrading her and maintaining her as best I know how and can afford.
As with automobiles - one will never go wrong with purchasing a classic (or new) Corvette, Mercedes Benz, Mustang, Jaguar, BMW, etc. because there's always a mob of passionate buyers looking for a well maintained model and you can always enjoy a great return on your investment so long as you don't crash... or sink it. Popular designs hold their value.
I'm not saying there isn't a market for classic beauties from a by-gone era... but there are less available and a smaller market for them.
I don't have enough experience to judge what sort of vessel design offers the best value / performance / comfort / safety ratio... but I do know I've never been on a boat I didn't like.
As with lovers... the choice is entirely up to you and you alone.
Happy Hunting.
Kirk
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05-17-2011, 06:33 PM
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#4
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Lieutenant
Join Date: Apr 2009
Posts: 86
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Gentlemen,
With regards to the Sparkman & Stephens designs, thank you for your comments. They are really appreciated. You are also preaching to the converted! I actually fell in love with a Hughes 38’ sloop that dated (1968?) from before the North Star variation. I believe that makes it a mk I? I don’t know if I am going to get that one or not but I have always had my eye out for something in the genre. The Hylas is another example of a beautiful boat, and I am filling away your comments for reference, never have had the opportunity to sail aboard one.
I am not really in the market at the moment for my own boat – life has a strange way of throwing curveballs at you which seems to keep me from getting enough hard cash together. For the time being I will have to keep sailing on other folks boats, when I can, and dream of getting my own. Most of my points for discussion are merely that. It keeps me amused!
Kevin
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Kevin Barr
Ottawa, Canada
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05-18-2011, 03:46 AM
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#5
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Moderator
Join Date: Jun 2007
Home Port: Washington DC
Vessel Name: SV Mahdee
Posts: 3,236
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For more than half of the 20th century, the racing rules really did make the push for overhangs on the bow (and stern). German Frers (Senior) was the first to design an ocean racing boat with a reverse transom. That was in the early 1950's. Everyone found the boat to be really ugly--but had to admit it was fast, fast, fast. He was a much desired yacht designer for his entire career. He sent his son (by the same name) to apprentice/work with Sparkman and Stephens in the mid-1960's. Then, the son came home to the family business that GF Sr. started in the late 20's, the son became very well know as an excellent yacht designer--well known for his Hallberg-Rassy designs as well as numerous semi-custom Hylas cruising yachts.
Some boats were built for the ocean and cruising--not to copy a racing hull built to a racing rule, not designed to make people think it will be fast--just for ocean cruising. They might have a bit of bow overhang to please the eye and they may or may not have a bit of overhang on the stern--or a reverse transom.
Fair winds,
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05-18-2011, 03:48 PM
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#6
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Rear Admiral
Join Date: Mar 2007
Home Port: Hamburg
Vessel Name: Aquaria
Posts: 281
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The "Length of waterline" is coming to my mind, important for the theoretical over all hull speed.*
Back then our big boats with s-shaped hulls were designed as displacement hulls. The maximum speed was in close correlation to our legth of the water line. The longer the water line, the higher the hull speed. Surfing down a wave was the absolute exception - most times we were stuck between the bow wake and a tremendous stern wake and a breathtaking deep trough at the beamiest point of our hull* when the wind was pushing hard. But the needle of the speedometer seemed to be glued to the 8kn mark.*
If I got things right, the designers added overhangs to extend the waterline to overcome this effect to some extend. (The longer the wave system, the faster it travels - if I remember my physic lessons right)
Today everything is different. Hulls are U-shaped with deep reaching keels and spade rudders hanging below beamy flat stern sections. And all that is built out of new, light material. *These *hull designs can "leave" the self produces wake system and glide over the water. Like our little centerboarders we chased over the water back then. A perfect example of todays cruising boat design might be *the dutch designed and built * Atlantic .
So, there is no longer a need for a long waterline in connection with overhangs to gain speed. *Todays harbour fees pushed the developements towards no overhangs (as Kirk already mentioned), *and as the demand for more space on a given over all *boat length and (at least here in Europe) it is a matter of taste as hulls with no overhangs are the latest fashion. *(And the hull colour must be grey.)
Our neighbouring boat is an * * esse 850* * and people stop looking at that boat and not at ours (a 1972 built IOR-half ton with beautiful overhangs)*** .*
Uwe
SY Aquaria
: Germany, Background, Cruising/Sailing the German Bight
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05-18-2011, 10:03 PM
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#7
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Moderator
Join Date: Jun 2007
Home Port: Washington DC
Vessel Name: SV Mahdee
Posts: 3,236
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Aquaria, you're right about new light displacement hulls in the racing world changing the methods of cheating the racing rules so that long overhangs don't really work so well!
Those (pre-light displacement days) racing rules pushed people to use the shortest "resting" waterline possible while designing in as much length of waterline (while underway) as possible by adding those overhangs. If the rules weren't in place, we'd have seen many more of the medium to heavy displacement hulls with small overhangs or even plum stem. Our boat was built for cruising not racing: it has a plumb bow and moderate stern overhang and was built way back in 1931. Its form copies the Brixham sailing trawlers, though it has a cutaway fore keel. Lyle Hess designed cruising boats with similarly vertical bow and very little stern overhang. Once one gets away from racing rules, even in the medium to heavy displacement hulls, we find lack of overhang on the bow and only enough overhang on the stern to provide a good break with the stern wave.
To allow the boat buoyancy, some boats with very little bow overhang have a narrow fine entry at the water and then flare up towards the deck. The vertical stem and a fine entry without that flare makes for a very wet foredeck.
Cruising boats have many times copied the popular racing boats of the era because the cruising boat owners didn't often fully understand the boat designs anyway. When the wanna-be cruiser sits down and really takes a look at boat design for cruising (e.g. they sit down with a Naval architect or boat builder who can educate them) they will often get away from all the racing accoutrement and really design or purchase a boat built for cruising--not something for round-the-buoy-racing or a compromise of club racing and overnight weekend cruising.
Fair winds,
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