The official details of the new America’s Cup class rule for the new boats have been announced. The new boats will be 90ft overall, have a draft of 6.5m and a displacement of 23 tonnes. Unlike the previous rule that attempted to control the shape of the hull, class rule is a box rule with hard limits on key dimensions.

While the overall length and the displacement don’t appear to have changed drastically, (Last season’s Version 5 boats were around 23m LOA with a displacement of 24 tonnes,) the big difference comes in the increased draft (4.1m to 6.5m) and waterline length (20m to 27m) which will serve to increase the righting moment and hence power dramatically and lead to significantly larger sail plans.

In essence the new boats look set to deliver more speed and a bigger challenge for the crews who will be manhandling much larger sail plans, but the announcement could see another change in the current Cup saga, that of the dispute between Oracle and the Defenders.

In the recent and well documented dispute over the Protocol between these two sides that has led them into the New York Supreme Court, Oracle claimed that it wanted to see the types of boat that the Defender had in mind for the 33rd America’s Cup. Until now ACM’s position had been that Oracle had to join the party and sign up for the next event in order to be a part of the process in which the Challengers had their say over the new boat.

Initially there were no plans to make the rule public in the early stages but the last minute decision reveal the rule from the outset must surely be a means of removing what the Defenders see as the last stumbling block from Oracle to see the dispute resolved before the Judge Cahn of the New York Supreme Court comes back with his decision.

At the time of writing there had been no official comment from BMW Oracle, but if and when there is, October 31 2007 could turn out to be one of the biggest days for the new America’s Cup.

Keep watching.

CLICK HERE For a pdf version of the official rule 

The official statement from ACM announcing the new rule read as follows:

AC90 Rule is born

Valencia, 31st October 2007 – Today AC Management, as scheduled, published the AC90 Rule marking an exciting milestone in the path to the 33rd America’s Cup. This rule has been crafted over the past six weeks through a des ign consultation process with all entered challengers, the Defender, and headed by Tom Schnackenberg as the class rule and competition regulations consultant for ACM.

Designers from all six entered teams have met regularly since the design process began on 15 September. Tom Schnackenberg comments on the sessions: “The process has been an invigorating one with the challengers helping enormously in making improvements to the rule. It is amazing how inventive people are in this environment, bouncing ideas off each other, these past six weeks have been a very enjoyable experience.”

The AC90 Rule, in brief, will be 90ft overall maximum length, 6.5m in draft whilst racing and will have a displacement of 23tons. This last parameter was defined by the challengers on their request. Tom adds some insight: “In writing the AC90 Rule we have used the experience gained in forming Version 5 of the America’s Cup Class rule. We have tried to keep it simple because of the short timeframe, while also taking care not to ignore the lessons of the last 18 years of the ACC. The rule is a box rule rather than a rating rule and differs greatly to Version 5 in that the yacht will be big, fast and much more demanding.” ;

Juan Kouyoumdjian, principal designer for British challenger, TEAMORIGIN, comments on the result of the design sessions: “To sit in a series of meetings chaired by Tom Schnackenberg and write a class rule for something as significant as the boat to be used for the America’s Cup has been an honour for me personally and a really inspiring experience. The profile of designers, engineers and naval architects representing the challengers and the Defender is, as always, really special. This has been an efficient and productive process and the boat itself will be spectacular: challenging to design, to sail and to race.”

John Cutler, technical director for Desafío Español, adds his take on the result: “We are happy with the process. It has been a lot of hard work for all the teams, the challengers and the Defender, and there have been a lot of changes. The boat will be exciting to sail, a challenge to design and also a challenge for the crew to master. It will provide exciting racing.”

As far as the next steps towards the 33rd America’s Cup are concerned, Tom Schnackenberg will continue the dialogue with the challengers and the Defender to finalise the Competition Regulations for a 2009 event.