BoatsNeptun 31

Neptun 31

Masthead Sloop · Fin Keel · 1970–1973

An IOR-rated 9.3-metre fin-keel sloop from the early seventies, designed with a 33% ballast ratio for coastal stability

Designed by Anton de Dood Miglitsch.

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 moderate displacement on a moderate beam gives 18 — a quick, lively motion that feels every wave.

Comfort ratio 18
CoastalBluewater

2.07 — right around the 2.0 line, the edge between coastal and offshore.

Capsize screening 2.07
LightHeavy

206 — moderately heavy for her waterline, a balanced cruising weight.

Displacement / length 206
EasygoingPowered-up

10.4 — modest power for her weight; easygoing rather than lively, and happier with a breeze.

Sail area / displacement 10.4
TenderStiff

33% of her weight is ballast — on the tender side; she'll heel readily and want a reef sooner.

Ballast 33%

A balanced, easily-driven cruiser — comfortable and forgiving for coastal work.

The record

Full specifications

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

Dimensions
Weights
Ballast / displacement
33.3%
Rig & sail area
Rig
Masthead Sloop
Ratios
SA / displacement
10.4
Displacement / length
205.8
Comfort ratio
18.3
Capsize screening
2.07
Hull speed
6.5 kn
Pounds / inch immersion
784
Hull
Hull type
Fin Keel
Construction
Fiberglass
Production
Years built
1970–1973
Designer
Anton de Dood Miglitsch
Builder
Neptun Boote GmbH, Co. KG

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.

Maestro Boats 319.30 mSame hull familyNear-identical lengthAn E.G. van de Stadt-designed IOR 1/2 ton racer with a high sail area-to-displacement ratio for spirited performance
Jeanneau Rush 319.13 mSame hull family0.2 m shorterA Ron Holland-designed IOR half-tonner that served as the official boat for the Tour de France à la Voile
C&C Yachts 30-29.12 mSame hull family0.2 m shorterA performance-oriented masthead sloop with a fin keel and spade rudder, designed by C&C for balanced club racing
Spirit 329.48 mSame hull family0.2 m longerA Jacques De Ridder-designed IOR 23-footer built for nearly two decades as a stiff, masthead-rigged fin-keel sloop
First 30 E (Beneteau - Berret)9.30 mSame hull familyNear-identical lengthA 1981 International 1/2 Ton Cup winner based on the King One design, built as a masthead sloop for competitive racing
Brresen Badebyggeri Knarr9.24 mSame hull familyNear-identical lengthA classic Erling Kristoffersen-designed fractional sloop with a deep ballast ratio, built in wood since 1946 and fiberglass since

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

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