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Sailboat

Monsun 31

1974 — 1982
Designer
Olle Enderlein
Builder
Hallberg-Rassy
Hull Type
Long Keel
Construction
FG

Dimensions

Length Overall
30.75 ft / 9.37 m
Waterline Length
24.67 ft / 7.52 m
Beam
9.42 ft / 2.87 m
Draft
4.58 ft / 1.40 m
Displacement
9,250 lb / 4,196 kg
Ballast
4,200 lb / 1,905 kg
drawing

Rig and Sails

Type
Masthead Sloop
Reported Sail Area
414.00 ft2 / 38.46 m2
Total Sail Area
413.51 ft2 / 38.42 m2
Mainsail
Sail Area
188.60 ft2 / 17.52 m2
P
32.80 ft / 10.00 m
E
11.50 ft / 3.51 m
Mast Height
Foresail
Sail Area
224.91 ft2 / 20.89 m2
I
37.80 ft / 11.52 m
J
11.90 ft / 3.63 m
Est. Forestay Len.
39.63 ft / 12.08 m

Spinnaker

SPL/TPS
ISP

Auxilary Power

Make
Volvo Penta
Model
MD 11 C
HP
?
Type
Diesel
Fuel Capacity
32 gals / 121 L

Accomodations

Water Capacity
43 gals / 163 L
Holding Tank Capacity
?
Headroom
?

Calculations

Hull Speed
6.66 knots
Sail Area/Displacement
15.03
under powered
Ballast/Displacement
45.41
stiffer, more powerful
Displacement/Length
275.03
heavy
Comfort Ratio
27.02
coastal cruiser
Capsize Screening
1.79
better suited for ocean passages

Notes

Launched in 1974 the Hallberg-Rassy 31 Monsun is a no-nonsense offshore cruiser with excellent build quality and sturdy enough for the needs of any long distance sailor. The boat is blessed with good accommodation, a secure feel, and eye-catching lines. These all had a parts to play in her notable success as the all time best seller for the prestigious Hallberg-Rassy brand.

Performance is mediocre due to her relatively heavy displacement, she does not point very high in light winds but this is not the reason sailors buy the Monsun 31. It’s her stability in the water that inspires confidence in offshore conditions – she gives an almost leisurely feel, and it’s this that’s earned her an excellent reputation among sailors.

Overall this 31-footer from the 1970s is sought after and this is reflected in her high price. You’ll find few owners looking to sell their boat.

History

The Monsun 31 bares the distinction as the first all-new design from the Hallberg-Rassy yard after the merger of the Rassy and Hallberg boatyards in 1972 that formed the company name. The new company came into existence when German expatriate Christophe Rassy bought the competing and well-respected Hallberg yard when it was time for its founder, Harry Hallberg, to retire.

At the time, Rassy was successfully building his Rasmus 35, a sturdy centre-cockpit cruiser, while Hallberg was producing four boats ranging from 24 to 33 feet. Of particular trouble was Hallberg’s Mistress 32, a very racing oriented design that competed successfully in the IOR half ton class. She was in full production and was at boat that was both expensive to build and sold relatively cheaply – this was terrible business and Hallberg-Rassy needed something new.

Rassy approached Olle Enderlein to draw up a boat similar to the Rasmus 35 but smaller and sleeker. The new boat had to have an interior that appealed to couples and for that it was important to have levels of comfort. Enderlein based the layout of the new interior on the Mistress but was much simpler, more streamlined and straightforward to produce and therefore affordable.

Production started in 1974 and a total of 904 boats were built until production ceased in 1982 when the boat was superseded by the Hallberg-Rassy 312 (launched in 1979).

Specifications

LOA: 30′ 9″
LWL: 24′ 8″
Beam: 9’ 5″
Draft: 4′ 7″
Displacement: 9,250 lbs.
Ballast: 4,200 lbs.
Sail Area: 430 sq. ft.

Water: 43 US Gal.
Fuel: 32 US Gal.
Engine: 23hp Volvo Penta MD11C

Designer: Olle Enderlein
Builder: Hallberg-Rassy
Year Introduced: 1974
Year Ended: 1982
Total Built: 904

Also Known As: Monsun 31

Similar Boats

Hallberg-Rassy 312

Hallberg-Rassy 310

Hallberg-Rassy 31

Moody 31

Hallberg-Rassy 352

Hallberg-Rassy 35 Rasmus

» The official Halberg-Rassy website, information on the Hallberg-Rasssy 31 Monsun
» Danish Monsun 31 Owners Club


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