Licensed builder Cape Performance Sailing builds the boat in Cape Town. Originally created for racing in South Africa, the Cape 31 has since developed into a fast-growing class on European and global circuits.
Design and Construction
Mills gave the Cape 31 low freeboard and aggressive chines, intended to maximise form stability in a breeze while limiting wetted surface when the boat is upright in light air. A single chine runs the length of the hull. Above it, the topsides remain close to dead vertical all the way to the transom, while the hull has almost zero deadrise anywhere—a shape Sailing Magazine described as very sexy in profile.
The plumb stem has its top nipped off to reduce windage and clean up airflow around the foot of the jib. To control costs, the boat uses a GRP hull with Corecell foam and an epoxy deck rather than exotic prepreg construction. Even so, it carries a carbon mast and a very high-aspect carbon-fibre rudder.
That rudder is positioned about four feet forward of the transom. The placement keeps the centreline blade buried as the boat heels, rather than allowing it to breach as it would farther aft.
Cockpit and Crew Geometry
One of Mills’s signature ideas on the Cape 31 is its ramp cockpit. It begins aft as a conventional well, then kicks upward at 11 degrees around station 7.5 and fairs into the bow deck, completely eliminating the usual step down into a cockpit box.
The cockpit is very wide, with a centre console that brings sail controls within the helmsman’s reach. Its geometry also allows the crew to keep their weight centred and low during manoeuvres.
The strict one-design rules require an owner-driver and limit total crew weight to 595 kg, which usually means seven people aboard. No more than three professionals are permitted, preserving the amateur ethos Laidlaw wanted.
Rig and Sail Plan
The Cape 31 is a fractional sloop with a double-spreader carbon mast, 20 degrees of spreader sweep and rod rigging. The boom is aluminium.
Its sail inventory centres on a square-top mainsail, J1 and J2 jibs, and a heavy-weather jib. Downwind sails include a range of asymmetric gennakers: A1.5, A2 and A4.
At a loaded displacement including crew, the SA/D is 29.14. The builder claims the boat sails upwind at 7.5 knots, planes in 12 knots of breeze and exceeds 20 knots downwind. Writing in Yachting World, one owner reported that his boat, Katabatic, peaked at 21 knots last season.
Racing Performance and Class Success
The Cape 31 wasn’t designed to fit any single rating rule, yet it has proved highly competitive under IRC, CSA and ORC. Results include an IRC2 National Championship and a 1-2-3 finish at the UK IRC Nationals. The class is also a two-time overall winner of Les Voiles de St Tropez.
The builder claims the Cape 31 is the only one-design currently winning on IRC and other rating systems. In a little over a year, 25 boats were sold into England and Ireland, with at least 50 racing across Europe.
Transport and Auxiliary Power
A 15 hp Yanmar diesel confirms that the Cape 31 is a proper keelboat rather than a dinghy. Its two-piece mast allows the entire boat and rig to fit inside a 40-foot container.
An optional tilt trailer allows legal towing around the globe. Owners can therefore ship or trail the boat between regattas without specialist breakbulk transport.
The Verdict
The Cape 31 is a focused one-design racer that punches well above its length. It combines relatively low-cost epoxy construction with a high-performance carbon rig and a clever ramp cockpit that keeps crew weight where it helps most.
Strict class rules protect its amateur spirit, while the container-friendly transport package makes international campaigning realistic. This isn’t a cruiser, however, and it shows its teeth only in racing hands.
Pros
- Competitive under IRC, CSA and ORC without being optimised for a particular rule
- Ramp cockpit eliminates the step down and helps keep crew weight centred
- Container and tilt-trailer transport support global regatta campaigns
- Forward-mounted carbon rudder stays submerged when the boat heels
Cons
- Strict one-design, owner-driver and professional-crew limits restrict how the boat can be used
- Low freeboard and a race-focused hull make it unsuitable for cruising
- The amateur-driven class permits no more than three paid professionals aboard
