As the J Class gears up for a showcase regatta that will form part of the 35th America’s Cup in Bermuda in 2017, the fleet is growing. The J Class J8, from an unbuilt 1935 Frank Paine design reimagined by Hoek Design, will launch in the Netherlands next month, and a Swedish design, J11, is being developed.

In addition to these boats from (as the rules stipulate) original designs, J9 is ready to go straight into construction at Holland Jachtbouw. Andre Hoek, whose company Hoek Design has carried out exhaustive tests on all the super-Js, believes J9 could be the fastest and finest yet.

Ten Js were originally built between 1930 and 1937, while a number of other striking designs were drawn but never saw the light of day. The new J9 project is one of these. The original hull lines were drawn in 1936 by Frank Paine, the designer of Yankee. The design was commissioned by Gerhard Lambert, who owned Yankee and the three-mast schooner Atlantic.

“The yacht we now call J9 was never built as Lambert did not win the right to defend the America’s Cup in 1937,” explains Andre Hoek. “But Paine’s template for a super-J with the maximum allowable waterline length impressed back then and still does so today.

“The term ‘super J’ was used with good reason. During the early 1930s the waterline of the Js grew from around 80 feet in 1930 to 83ft in 1934 and 87ft by 1936. The latter were significantly faster and dubbed the super-Js because of their increased size. As Ranger and Endeavour II – which competed for the last America’s Cup race in 1937 – were both 87ft, the romantics among us can be forgiven for seeing another reason for calling them super!”

“Frank Paine designed her with a waterline length of 88ft as he was convinced that the extra foot in length would more than make up for the penalty on sail area she would have incurred,” says Andre Hoek with the air of someone who has spent a great deal of time studying his subject.

“The design also featured a fascinating hull shape with a new underwater body in the foreship. When she is finally launched, I am certain that this hull shape development will enable J9 to perform extremely well both upwind and downwind in light and heavy airs.”

Like the other three Js optimised by Hoek Design, the 21st-century version of J9 has been designed on the basis of continuous longitudinal framing in order to reduce longitudinal deflection and to reduce the head stay sag. She has been extensively optimised under the new J-class handicap system and extensive studies have been completed into key factors such as the displacement-length ratio, stability, mast position and sail area.

All the Hoek designs – whether eventually built in the 1930s or not – have been analysed with an in-house velocity prediction program. Purpose-made for these hull shapes, the VPP was calibrated on the basis of tank tests carried out at the Marin institute and the aero-dynamics were tuned using wind tunnel data.

The best performing Js in this initial research were then further analysed using Numeca’s Computational Fluid Dynamics (CFD) software. The first to be built was Lionheart, JH1, which was redesigned and reconfigured by Hoek Design. Launched by Claassen Jachtbouw in 2010, she has been very successful on the race course, winning three of the four major regattas in 2014 by significant margins.

The America’s Cup organisers are to set a series of races in Bermuda in 2017, followed by a match race between the two best yachts in the regatta.