The VPP data show speed of 16 knots in 20 KTWS downwind and upwind speed of 7 knots. 

The GP 33 rule, defined as new level class from ORC is a box rule, it defines the principal measures of the hull with a maximum length of 10 metres and the beam max of 3 metres, fix the rig and sail parameters, fix the max dr

The design work for the correct hull shape start with a full research on the basic parameters, from the beginning I decided to go to the maximum beam allowable by the rule and the maximum dynamic length water line and minimum displacement, the parameter involved in the research was the BWL, prismatic and LCB position.

I decide preliminary matrix 3 *3 of combination, and a second more refined 3 *3 after a preliminary screening with a wider net, all the boat was tested with CFD and post processing with VPP, I was advanced   because we had already done for the same typology a research for our GP 26 and GP 42.

A lot of attention in the design process was to the trasooom area immersed to make the dynamic length as long as possible without be immersed with an increase in drag.

The rule requires as scantling to conform the ABS rule, the result is a strong but light structure with the use of all carbon fibre and epoxy laminates.

All the engineering both of hull and keel was done inside in Ceccarelli Yacht Design.

The fin has a conservative plan form area not a lot tapered, with the idea to be all round, smaller fin are faster downwind but could be dangerous at low speed   not to generate enough lift.

The fin is a high resistance steel type Weldox 700, welded fin with a carter only to obtain the correct shape in plan form and section, according to the hydrodynamic study done, the foils are laminar; it support a lead cast and finally CNC shaped bulb, the design is a very long and with a low centre of gravity.

The bulb shape also was tested and optimized with the CFD (computer fluid dynamic) research to obtain the minimum drag versus lower centre of gravity.

The rudder build by ISOTOP has the stock and blade build in carbon fibre and a high aspect ratio shape, with the rudder in area we was less conservative and is in direction of a small rudder.

The rig build b King Mast in Argentina also is a two spreader rig without runner and jumper.

The minimum weight of the mast is not too low so you the choose was oriented in found the correct shape considering the aero drag and stiffness.

The sail plan dimension are fixed, not the shape, mr. Konrad Smolen choose for his boat to go to North Argentina to order the sails, that will be designed in shape by the designer Juan Garay, that worked with me as designer of the sails of +39 challenge.

There was done a testing with the CFD also of the upwind sails to arrive to found the correct balance of the boat.

The deck lay out is racing oriented, with a wide, large and shallow cockpit for easy movement of the crew.

All the deck hardware is from Harkin, blocks and winches and Spin lock for stopper, pad eyes, tiller extension.

The cabin is designed around the rule with the minimum volume.

Below the interiors have four berths and are racing oriented.

The boat could be used also in ORC with a preliminary GPH of 560 sec mile or in IRC both in inshore and offshore races.

From the same mould for next season the yard could build other boats that could be optimized according to the request of the owner in the deck lay out and appendages design.