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Old 03-19-2003
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Boat length and solo sailing

I came across the data from 1898 to 1988 on solo sailing circumnavigations and would like to share the following condensed information regarding boat lengths:

Smallest: 13'' ( an Aussie)Biggest: 76'' Catamaran (France) Grouping by 5 foot samples, the most popular length was 26-30'' by a factor of 2 or 3 compared to other sample intervals.

The boat lengths did form a symmetrical Bell Curve around this group. The single most popular length seems to have been 26 feet.

Looking at the data from a lognormal vs. occurrence view, the Median boat lenght (50/50 longer/shorter) was 31.4 feet, and the Statistical Mean length was exactly 10 meters, or 32.8 feet.

This information does not include the last 15 years. I will try dig that up.

As far as frequency of solo circumnavigations, of course, the ''80''s were the highest, due to good fibreglas construction and availability of good boats. While many large boats did it then, curiously, so did the full gamut of lengths:

conclusion?? perhaps it is that boats are getting better, not necessarily longer?
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Old 03-19-2003
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Boat length and solo sailing

I think that a better way to look at this is by displacement. The traditional rule of thumb was that a proper cruising boat needed a displacement of three to five long tons of displacement per person. In recent years, better hardware has permitted that ideal weight to creep up a little and the current trends in loading boats up with modern equipment and all of the comforts of home, has pushed that range up to closer to 11,000 to 15,000 lbs. of displacement per person.

Historically, a cruising boat with a 3 to 5 ton displacement would have been 28 to 32 or so feet in length. When you look back at earlier distance cruisers, they tended to use boats that were comparatively short when compared to the norm today. This shorter length resulted in a high length to displacement ratio (L/D) typically in a 250 to 350 range. These old style cruisers were typically pretty shallow, and carried a larger percent of their weight in their hull and rig resulting in a lower ballast to weight ratio and consequently less stability. As a result they also tended to have less sail area and lower aspect ratio rigs in proportion to their displacement with a SA/D ratio in the range of 14 to 16 or so.

But using modern materials and a better understanding of marine structures and hydrodynamics a 3 to 5 ton distance cruising boat can safely have an L/D of 160 or so and still have a higher ratio of ballast to displacement than its predicessors. This lighter L/D typically means a more easily driven hull and the greater ratio of ballast to displacement placed lower in the water can result in the ability to carry more sail. On more modern designs a SA/D ratios above 20 are not all that unusual. That combination means that the boat has enough sail area to sail at a reasonable speed in light air and an sufficiently easily driven hull to get by with less sail area in a blow.

Jeff
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Old 03-20-2003
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Boat length and solo sailing

My list of solo boats only gave length and not seaworthiness parameters. To carry on with this, I did take the 32 foot length from that investigation and plot up the D/LWL and SA/D of 55 production sailboats that were more or less 32 feet long.

The plots clustered around D/LWL of 280 and SA/D of around 17. Not really a surprize.
They gathered between 190 to 390 and 14 to 21.

The 32 +/- foot boats that were in this range were: Aloha 32, C&C32, Ericson, Nicholson, Ranger 33, Sabre34, Tanzer 10.5.

Boats with heavier displacement but still higher performance numbers for SA/D were of personal interest: Dufour 31, Islander 32, Island Packet32, Morgan 324, plus Ericson32 and Sabre 34.

The boats were not sorted by racer/cruiser/bluewater, just initially by about 32 feet of length. I can''t verify their numbers easily, they''re off a website. So with those disclaimers, here''s my shortlist!

Length matters little: it seems its the motion in the ocean that causes the emotion
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Old 03-20-2003
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Boat length and solo sailing

Type and quality of hardware make a huge difference for single handing. A good autopilot, good winches and well thought out sail reefing gear make it possible to single hand large boats. Everything needs to lead to the cockpit.
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Old 03-20-2003
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Boat length and solo sailing

When you say,"Boats with heavier displacement but still higher performance numbers for SA/D were of personal interest: Dufour 31,Islander 32, Island Packet32, Morgan 324, plus Ericson32 and Sabre 34."

I have to question your idea that this group represents "still higher performance number". Some do and some don''t. For example, I want to point out that Island Packet in particular publishes sail area numbers that are not consistent with the usual practice for calculating sail area. The normal published sail area and the area that is used by convention to calculate SA/D is the 100% foretriangle. Island Packet uses the sail area of their genoa. This results in an artifically high published SA/D.

Jeff
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Old 03-21-2003
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Boat length and solo sailing

Your comment shows the follies of relying raw data. Reducing this short list--which is really an attempt at an objective starting point-requires a boat-by-boat review, begins with groundtruthing the basic numbers, and moves on to build, availability, and idosyncracies. The final pick still needs sea trials and fit the owners lifestyle and local waters--but may be from a stable of good boats, at least. I guess that was the objective. so many boats, so much information, so little time on the water!
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