Beta Marine

Beta Marine

Sailboat Specifications

Hull Type: Swing Keel
Rigging Type: Fractional Sloop
LOA: 20.50 ft
LWL: 17.00 ft
S.A. (reported): 190.00 ft²
Beam: 7.00 ft
Displacement: 1,250.00 lb
Ballast: 400.00 lb
Max Draft: 4.00 ft
Min Draft: 1.00 ft
Construction: FG
Ballast Type: Lead
First Built: 1970
Last Built: 1977
# Built: 2600
Builder: Clark Boat Co. (USA)
Designer: Don Clark

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Sailboat Calculations

S.A. / Displ.: 26.25
Bal. / Displ.: 32.00
Disp: / Len: 113.58
Comfort Ratio: 8.01
Capsize Screening Formula: 2.60
S#: 5.35
Hull Speed: 5.52 kn
Pounds/Inch Immersion: 425.20 pounds/inch

calculation mobile

2 nd ad half width

3rd ad full width

Rig and Sail Particulars

I: 22.50 ft
J: 8.00 ft
P: 23.00 ft
E: 8.75 ft
S.A. Fore: 90.00 ft²
S.A. Main: 100.63 ft²
S.A. Total (100% Fore + Main Triangles): 190.63 ft²
S.A./Displ. (calc.): 26.34
Est. Forestay Length: 23.88 ft

Sailboat Links

Builders: Clark Boat Company
Associations: San Juan 21 Class Association
Products: The Sail Warehouse
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Clark Boat Co. had previously built a number of One-Design Dinghy's, but this was the first 'SAN JUAN' and a huge success.
Designed displacement was 1250 lbs. but it was found that most ended up at 1400 lbs.
Thanks to Samuel Tricky for providing corrected information for this and number of other boats in this category.