B-31 (BOSTROM)

Beta Marine

Beta Marine

Sailboat Specifications

Definitions
Hull Type: Fin with rudder on skeg
Rigging Type: Masthead Sloop
LOA: 30.64 ft / 9.34 m
LWL: 25.98 ft / 7.92 m
S.A. (reported): 370.00 ft² / 34.37 m²
Beam: 9.06 ft / 2.76 m
Displacement: 7,782.00 lb / 3,530 kg
Ballast: 3,748.00 lb / 1,700 kg
Max Draft: 5.91 ft / 1.80 m
Construction: FG
Ballast Type: Iron
First Built: 1973
Last Built: 1988
# Built: 1000
Designer: Bruno Boström/Grandinsson

Auxiliary Power/Tanks (orig. equip.)

Make: Yanmar
Type: Diesel
HP: 8

Sailboat Calculations

Definitions
S.A. / Displ.: 15.12
Bal. / Displ.: 48.16
Disp: / Len: 198.12
Comfort Ratio: 23.32
Capsize Screening Formula: 1.83
S#: 2.50
Hull Speed: 6.83 kn
Pounds/Inch Immersion: 841.03 pounds/inch

calculation mobile

2 nd ad half width

3rd ad full width

Rig and Sail Particulars

HELP
I: 37.40 ft / 11.40 m
J: 11.98 ft / 3.65 m
P: 31.82 ft / 9.70 m
E: 9.19 ft / 2.80 m
S.A. Fore: 224.03 ft² / 20.81 m²
S.A. Main: 146.21 ft² / 13.58 m²
S.A. Total (100% Fore + Main Triangles): 370.24 ft² / 34.40 m²
S.A./Displ. (calc.): 15.13
Est. Forestay Length: 39.27 ft / 11.97 m

Sailboat Links

Designers: Bruno Boström
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Notes

Derived from the earlier Bostrum designed MARKAT 30. Also known as BOSTRUM 31. Most were sold as bare hulls or kits.