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40 Ft Racing Trimaran.

For Peter Bryant

  1. LOA 40 ft. (12.19m)
  2. LWL 40 ft. (12.19m)
  3. BOA 36.1 ft. (11.0m)
  4. DRAFT 1.5/7.2 ft. (0.46/2.2m)
  5. DISPL. 2000 Kgs

The brief for this design was to build a boat to win line honours in all the RORC (Royal Ocean Racing Club) series of offshore races. These are usually across the English Channel from England to France, including the Fastnet race. The boat should also be competitive in short “around the cans” racing in the UK.

Our recent success with Shockwave (a 34 ft Trimaran to my design) showed that on boat speed in flat water, Shockwave could keep up with, and often beat, the current 40 foot racers. After achieving first British boat home in the Around the Island Race in June 2001 aboard Shockwave, Peter Bryant was convinced that a 40 foot development of Shockwave and “Naia” would be a winner.

Peter is very interested in using the latest computer technology to gather data on the boat’s performance, and wanted to be able to use that information live while sailing. This meant that he would want to be in contact with the crew and at the navigation console at the same time. Therefore I included a raised chart table with a seat to one side, so that access into the hull was still possible when the navigator was seated at the computer array. This feature will also be very good for single or double handed sailing.

The general concept of the design is to keep the hull surfaces to a minimum to enclose the two berths and the navigation area. The beams are lifted to clear the water in conditions where there will be considerable water flowing across the hulls. At speeds of around 24 knots this water feels like a fire hose, and the crew needs to be able to sit clear of the spray. Thus the helmsman’s seat is out on the aft cross beam and only one crew remains in the cockpit to trim the main and the jib.

Three rudders are necessary on this boat because she can be sailed on one hull with the main hull nearly clear of the water. We found that the speed and power developed on “Naia” caused the main hull rudder to ventilate at speeds of around 20 to 22 knots. This placed a limit on top speed until we added rudders on the outriggers.

In previous designs we have found a gap in the performance between the point when the jib is too small and the Genoa is too large. This has been addressed by adding a larger Jib off the tip of the bow, thereby improving performance in wind speeds of around 8 to 14 knots.

The rig is drawn with a carbon wing mast of short cord. A large wing can close the slot when hard on the wind, thereby reducing the effect of the jib. With sheeting angles as low as 6 degrees, the jib leech is very close to the mast. Therefore a small wing will be more effective on this design. Swept back spreaders keep the mast in column.

Construction will be in Prepreg Carbon for all of the hull and beam structure, with Core-cel foam below the waterline, with Nomex honeycomb core for the rest of the structure. All up weight is predicted to be 2000 Kgs in racing trim including the weight of the crew.