Kelly KC40

The KC40 is today only a concept of an ultra-light speed sailing yacht, the details of which are very little known. She weighs only 4.5 tons, which is an incredible low weight for a 40-footer. For increase of stability designers suggest to apply water ballast - for its storage tanks in capacity of 750 litres on each board are provided.
The power structure of the boat is amazing - almost 25 square meters per ton of displacement. To control such a projectile you will need a very experienced crew with strong nerves.