BoatsThai MK IV

Thai MK IV

Catamaran, twin centreboards · Frac. Sloop (Rotating Spar) · First built 1958

A Rod Macalpine-Downie designed catamaran featuring a rotating spar and an ultra-light displacement for high-speed racing

Designed by Rod Macalpine-Downie, built by Sailcraft.

LOA
Beam
Draft (max)
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
Frac. Sloop (Rotating Spar)
Ratios
SA / displacement
88.8
Hull
Hull type
Catamaran Twin Cbrd.
Construction
Wood
Production
Years built
First built 1958
Designer
Rod Macalpine-Downie
Builder
Sailcraft

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The family

Boats like this

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

Paper TigerA Ron Given-designed catamaran with a rotating cat rig, built for amateur plywood construction and still actively racedMaricat 4.3A versatile Australian beach catamaran with a long production run and three distinct racing classes for all skill levelsTiger CatThe first one-design catamaran class in the US, derived from the 1959 One of a Kind Regatta-winning prototypeThom Cat 15A Menger-designed gaff-rigged daysailer with a high sail-area-to-displacement ratio for spirited performanceTopcat K4XA 115kg catamaran with a rotating fractional rig, available in Active or Touring versions with flat-top sail optionsTaipan 4.9A lightweight 4.95-metre catamaran with a rotating fractional rig that remains competitive in Formula 18 racing

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