Monday, 29 April 2013

Class 40 : New Jason Ker Design for Team Concise

Rendering of the new Team Concise design. Image copyright Jason Ker.

by Ned Collier Wakefield
With the 130th boat due to be launched this year, the Class40 represents one of the most successful ever genres of offshore racing yacht. Joining the fleet this year will be a new designer who has combined forces with an old team in a new initiative.

Jason Ker, former Principle Designer for the Team Shosholoza America’s Cup challenge, has penned the Forty(1)Design to a brief from Tony Lawson’s UK-based Team Concise. In addition to complying with Class40 rules, the aim of the new boat to become a one design within the Class40, while at the same time bucking the trend of escalating costs.

“At present one-off Class 40s cost more than 500,000 Euros to put on the water,” says Team Concise skipper Ned Collier Wakefield, who is managing the project. “The aim of the Forty(1)Design is for it to be competitive with the latest one-offs, but at a similar price to the racing spec production Class40s.”

300,000 Euros (ex sails, electronics, running rigging, shipping and tax) is set to be the price tag of the Forty(1)Design. Complete it will therefore cost a fraction more than the racing versions of existing production Class 40s, but will have a much higher spec as standard, including epoxy construction, optimised kick-up rudders, a high strength steel fin, premium deck gear package, premium mast, etc.

Image copyright Team Concise.

Beamy while retaining a narrow waterline, the Forty(1)Design features a chine and ‘chamfer’ (a cutaway gunnel) along the length of the hull. The latter lowers the boat’s centre of gravity and helps it comply with the Class40’s 90° inclination rule.

The cabintop extends forward of the mast and flares out aft, allowing a small sheeting angle for the jibs and a forward-facing window to be installed each side. As in the IMOCA class, cockpit protection is taken seriously on Class40s and for this purpose a ‘helming bubble’ is being developing that clips onto the side of the cabintop.  There is a single companionway, allowing for easy transportation of sails up on deck, while maintaining the convenience of a single pit area to starboard.

The Forty(1)Design cockpit stops short of the transom. This provides a optimised place to stack sails, removes flotation that inhibits the 90° test, while helping the boat achieve the mandatory 180° inversion test required for the Global Ocean Race.

At the transom there are VO70-style ‘batwings’, elevating the chainplates for the runners/spinnaker sheet turning blocks. As Jason Ker explains: “The higher you can get your sheeting point, the more range you can get out of each sail and the more evenly you can trim your sails through different wind angles.”

Image copyright Team Concise

The boat features twin kick-up rudders. Aside from preserving the rudders and reducing drag this allows high aspect rudders to be fitted, reducing the boat’s leeway and the amount of energy required for the autopilot to steer.

Down below, the new Class40 has a unique structure incorporating a keel tower and D0s where loads are effectively spread between the keel and rig. This, plus the use of a thicker core in the hull and substantial longitudinals, means there is less need for any lateral structure mid-ships, making it easier to shift sails fore and aft.

Water ballast is at the class permitted maximum of 750kg and each side is contained in a single long, thin tank to get the weight further outboard. To optimise the water ballast further there is no transfer pipe between the tanks, as the transfer pipe is included in the 750kg water allowance. Instead water is scooped up afresh on each tack with the help of a custom impeller and dumped straight out when not needed.

The Southern Spars rig will feature three swept-back spreaders, while North Sails and Team Concise have studied the sail plan in depth. The inboard chainplate position, allows for more efficient overlapping sails while still managing to achieve the desired tube stiffness, headstay load and low VCG.

The Forty(1)Design is currently under construction at McConaghy’s facility in China, where the Ker 40 and 46 IRC racers are also built. As standard the boat fulfils Cat 1 requirements (for transatlantic races). To achieve Cat 0 for the Global Ocean Race, simply requires additional watertight doors to be slotted in.

Team Concise is getting hull no1 of the Forty(1)Design. This is due to arrive in the UK in July. Its first regatta will be the Class40 Worlds in Plymouth over 17-20th August.

More information can be found at

Class 40 Rule

LOA: 12.19m
Beam Max: 4.5m
Draft max: 3m
Freeboard average: >1.1m
Displacement: >4500kg
Water ballast: <750lt side="" u="">
Highest sail height: <19m off="" the="" u="" water="">
Bowsprit: <2m u="">
Sail limit: <8 .="" span="">
Sail materials: All but two sails must be polyester, the spinnakers nylon
Banned construction materials: carbon, aramid, paper or aluminium honeycomb
Stability: Must right at 90deg inclination with 320kg applied to the masthead.