Pub Bragging Rights for your boat.

For our Moody 31:

Sail area to displacement (SAD): 19

Displacement to length: 271

Length to beam: 2.93

Theoretical hull speed: 6.76 knots

Capsize ratio: 1.95

Waterplane area: 154.55 ft2 (bit of a guess on that one)

Ballast to displacement: 37%

Comfort Ratio: 41


So, solid and unexciting - a bit like her owner, really.....
 
For Island Packet 350:

SAD: 18
Displacement to length: 283
Hull speed: 7.26
Capsize ratio 1.9
Ballast-displacement 47%
Comfort ratio 49

Funny - I got slightly different numbers from somewhere else a while ago - now I can't find the site!
 
Griffon Mk I

Sail area to displacement (SAD): 19
Displacement to length: 270
Length to beam: 2.81
Theoretical hull speed: 6.24 knots
Capsize ratio: 2.02
Waterplane area: 148.22 ft2
Ballast to displacement: 45%
Comfort Ratio: 33

Waterline beam is a guess. Should that be actual sail area, which is what I've used, or main + 100% foretriangle?
 
The thing that surprises me a bit here is the similarity between Jeanneau SO35 and Moody 346.
As mine is supposed to be a lightweight flibberty gibbet, and the Moody 346 the Stout Walking Shoes of Cruising, they are remarkably close.
Of course, my SO35 haas the much heavier Lift keel displacement and keel weight, so I guess that fudges the figures.
Having sailed Magna Cartas' fine Oceanis 400, I agree that his is more tender than mine, but again, prob due to the wing keel I have damping the roll effects.

The Island Packet Sail Area/Displacement was a shock at 19 though! I thought they were also conservatively sail planned.
 
SAD, indeed. Using the designer's figures, which I don't believe includes the weight of the water, fuel, crew and gear, I get:

Sail area to displacement (SAD): 19
Displacement to length: 205
Length to beam: 3.33
Theoretical hull speed: 7.67 knots
Capsize ratio: 1.81
Ballast to displacement: 41%
Comfort Ratio: 47

Adding in the weight of full tanks, anchor chain, anchors, crew and stores (3000 lbs or so), shifts the figures so:

Sail area to displacement (SAD): 17
Displacement to length: 244
Capsize ratio: 1.71
Waterplane area: 261.35 ft2
Ballast to displacement: 34%
Comfort Ratio: 57

No account is taken of the wing keel, which reduces pitching and rolling.

Oh ****! I've just admitted to wasting my time.
 
OK the Elizabethan 30

Sail area to displacement (SAD): 19

Displacement to length: 231

Length to beam: 3.19

Theoretical hull speed: 6.56 knots

Capsize ratio: 1.92

Waterplane area: 136.8 ft2

Ballast to displacement: 50%

Comfort Ratio: 35

However, is there any point in collating these results and putting them on a spreadsheet/website? It could be useful for any one looking for a purchase.
 
Re: Pub Bragging Rights for your boat.

Crikey, you need to get that comfort ratio up a bit. How about some nice cockpit cushions or a decent tea cosy?
 
Re: Pub Bragging Rights for your boat.

I've got one of those, but I used it as part of my sailplan calculations....
 
Re: Pub Bragging Rights for your boat.

Hee hee, started reading your blog and have got to Cherbourg and EBBs. Why don't blogs run earliest first, or am I just out of step as usual?
 
Re: Pub Bragging Rights for your boat.

The White Company sale on Friday, might see if I can pick up a nice sheepskin throw, that should sort it.
 
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