BoatsShearwater III

Shearwater III

Catamaran, twin centreboards · Frac. Sloop (Rotating Spar) · First built 1956

A 1956 restricted development catamaran featuring a rotating spar and lightweight construction originally sold as a kit

Designed by Francis & Roland Prout, built by Prout.

LOA
Beam
Draft (max)
Displacement
Hull type
Catamaran Twin Cbrd.

Is it for you?

Character

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

TrailerableBeam 2.29 m — inside the 2.55 m no-permit tow width across most of Europe, and the 2.59 m US and Canadian limit. About 120 kg of hull, so roughly 700 kg on a trailer: check that against your own towing rating.Ramp-launchableAbout 120 kg of hull, with a keel that raises or a draft shallow enough to float off a trailer — she can go back on the trailer at the ramp, not only into the water.Shoal draftDraws 0.18 m, board up where she has one — creeks, sandbars and thin anchorages most keels have to stay out of.
LightHeavy

30 — light for her waterline, so she is easily driven and quick to accelerate.

Displacement / length 30
EasygoingPowered-up

62.3 — a lot of sail for her weight; powered-up and eager, a real performer.

Sail area / displacement 62.3
  • Draws more than ~76% of boats her size on file
  • Narrower than ~78% of boats her size on file

Compared with 145 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
Rig & sail area
Rig
Frac. Sloop (Rotating Spar)
Ratios
SA / displacement
62.3
Displacement / length
29.9
Hull
Hull type
Catamaran Twin Cbrd.
Construction
Wood/FG/Composite
Production
Years built
First built 1956
Units built
1500
Designer
Francis, Roland Prout
Builder
Prout, Fairey Marine Ltd

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.

Supercat 154.65 mSame hull family0.4 m shorterA high-performance beach catamaran with a rotating spar and an exceptional sail-area-to-displacement ratio
Why St. John Feels Nothing Like St. Thomas E38116:38from Wildly Intrepid Sailing
Hobie 165.05 mSame hull familyNear-identical lengthThe most popular sailing catamaran ever built, featuring a rotating spar and boardless hull for high-speed beach sailing
Hobie Cat 16 Sailing - 5 days & 400kmfrom Igor Stropnik
Hobie FX One5.18 mSame hull familyNear-identical lengthA 5.18-meter single-handed catamaran featuring a rotating fractional rig and an exceptional 56.56 sail area-to-displacement ratio
Hobie Cat, 15 days & 1200km2:47from Igor Stropnik
Hobie Tiger 185.51 mSame hull family0.5 m longerDesigned to the Formula 18 rule, this 5.5-meter catamaran features twin daggerboards and a high power-to-weight ratio
4 day solo passage to the Greek town of Vasiliki 🇬🇷 & sailing cats with ​⁠@JOYRIDER TV26:10from Sam Holmes Sailing

The family

Related models

The designs closest to hers — usually the rest of the builder's range, sometimes the same hull sold under another name.

G. Prout SwiftA 1954 fractional sloop catamaran with a high power-to-weight ratio, originally offered as a kit or finished boatKingfisher IIIA Philip Rhodes-designed centerboard dinghy offered in multiple rig configurations and famously sold as the American 12

Keep looking

Nothing filmed of this one yet

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

Search the fleet for boats like thisAsk the fleet about the Shearwater III

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