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
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.
Hobie Tiger 185.51 mSame hull family0.6 m longerDesigned to the Formula 18 rule, this 5.5-metre catamaran features twin daggerboards and a high power-to-weight ratio
Hobie FX One5.18 mSame hull family0.3 m longerA 5.18-metre single-handed catamaran featuring a rotating fractional rig and an exceptional 56.56 sail area-to-displacement ratio
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 175.18 mSame hull family0.3 m longerA single-handed performance catamaran featuring a wingsail-style rotating mast and twin daggerboards for upwind speed
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
Alcort Inc. Catfish4.01 mSame hull family0.9 m shorterA 1964 George Patterson design, this ultra-light twin-board catamaran offers high-performance sailing in a 4-metre package
The family
Boats like this
Nearby designs by size, type, and era — worth a look alongside her.
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
Keep looking
Nothing filmed of this one yet
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