BoatsInternational One Design

International One Design

Fractional Sloop · Fin Keel · First built 1936

A Bjarne Aas-designed fractional sloop with a narrow beam and high ballast ratio, evolved from Norwegian wood to fiberglass

Designed by Bjarn Aas & Bjarne Aas.

LOA
Beam
Draft (max)
Displacement
Ballast
Hull type
Fin Keel

Is it for you?

Character

Where this design lands on the numbers a shopper trusts — read straight from her own ratios.

LivelySea-kindly

Her heavy displacement on a narrow beam gives 35 — a sea-kindly motion in a seaway.

Comfort ratio 35
CoastalBluewater

At 1.41 she sits well under the 2.0 line — a solidly ocean-capable hull for her size.

Capsize screening 1.41
LightHeavy

323 — heavy for her waterline, built to carry stores and ride steadily.

Displacement / length 323
EasygoingPowered-up

19.0 — plenty of sail for her weight; lively and quick to respond.

Sail area / displacement 19.0
TenderStiff

58% of her weight is ballast — very stiff, carrying full sail in a blow.

Ballast 58%

Built heavy and sea-kindly — a boat made to cross oceans and forgive a rough night.

  • Narrower than ~99% of boats her size on file

Compared with 2903 boats of the same type within a quarter of her length.

The record

Full specifications

The complete reference set — tap any figure to switch between metric and imperial.

Dimensions
Weights
Ballast / displacement
57.8%
Rig & sail area
Rig
Fractional Sloop
Ratios
SA / displacement
19.0
Displacement / length
322.5
Comfort ratio
34.5
Capsize screening
1.41
Hull speed
6.2 kn
Pounds / inch immersion
517
Hull
Hull type
Fin Keel
Construction
Wood
Production
Years built
First built 1936
Units built
250
Designer
Bjarn Aas, Bjarne Aas
Builder
Bjarn Aas, Able Marine

Boats like this, on the water

Nobody has filmed this one — but these are close.

Comparable boats the fleet has on camera: same type, within a quarter of her length. Open the boat, or watch the video — a timestamp means she only appears in passing.

Mistral 3310.19 mSame hull familyNear-identical lengthA former IOR half-tonner that transitioned from the Hallberg brand to the Hallberg-Rassy line during its 1968-1976 run
C&C Yachts 3410.21 mSame hull familyNear-identical lengthOffered in both deep keel and keel/centerboard configurations, this 1977 masthead sloop balances performance with versatility
Cal Boats 3410.13 mSame hull familyNear-identical lengthA masthead sloop with a fin keel and spade rudder, favoured by Jensen Marine founder Jack Jensen for personal cruising
Catalina Yachts 31610.06 mSame hull familyNear-identical lengthA 2024 6 Series fractional sloop featuring a deep-draft fin keel and spade rudder for precise coastal handling
Mirage 3310.21 mSame hull familyNear-identical lengthA Robert Perry-designed masthead sloop offering a balanced, performance-oriented cruiser profile in a 33-foot hull
Dehler Yachts 3410.10 mSame hull familyNear-identical lengthAn IOR 3/4 ton racer-cruiser designed by Van de Stadt, offering a balanced performance pedigree in a comfortable hull

The family

Boats like this

Nearby designs by size, type, and era — worth a look alongside her.

Keep looking

Nothing filmed of this one yet

Two ways to keep looking — both search what the fleet has actually recorded.

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