BoatsAST Ltd. Jumpahead

AST Ltd. Jumpahead

Catamaran, twin centreboards · Fractional Sloop · First built 1948

A pioneering UK production catamaran from 1948 with a high power-to-weight ratio, designed by Bill O'Brian

Designed by Bill O'Brien.

LOA
Beam
Displacement
Hull type
Catamaran Twin Cbrd.

The record

Full specifications

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

Dimensions
Weights
Rig & sail area
Rig
Fractional Sloop
Ratios
SA / displacement
51.4
Hull
Hull type
Catamaran Twin Cbrd.
Construction
Wood
Production
Years built
First built 1948
Designer
Bill O'Brien
Builder
AST Ltd, Grampian Marine

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Hobie Tiger 185.51 mSame hull family0.6 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
Hobie FX One5.18 mSame hull family0.3 m longerA 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 165.05 mSame hull family0.2 m longerThe 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
Supercat 154.65 mSame hull family0.2 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

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.

Apollo 18An early A-class single-handed catamaran featuring a rotating spar and an exceptionally high sail-area-to-displacement ratioAlpha Cat 18A 1970 Tom Roland design featuring a rotating spar and twin daggerboards on an ultra-light 136-kilogram hullAqua Cat 12Once the world's largest one-design catamaran class, this lateen-rigged twin-board design remained in production until 2003Upstart 16A high-performance fractional sloop designed by Macalpine-Downie and Gibbs, featuring a light displacement for speedG. Prout SwiftA 1954 fractional sloop catamaran with a high power-to-weight ratio, originally offered as a kit or finished boat

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