Onboard AC75 "Luna Rossa"
A concentration of technology lead by 11 men
The AC75 is an extremely complex boat. A 6.5-ton sailboat that reaches a speed of 50 knots, lifted above the water and relying uniquely on an element of a few square meters immersed in the water, the wing foil, seems like a miracle of physics.
To achieve this concentration of technology it has taken three years of development, experimentation and work. Under the deck Luna Rossa hides a complex system of valves and hydraulic pumps used to raise the arms, rotate the mast and adjust the sails.
The energy used for handling the boat is produced by 8 grinders, 4 on each side. But their role is not limited only to this; each of them has specific tasks in the management of the boat and contributes to the manoeuvres and trimming of the systems.
Two of them, one on the left side and the other on the right, are mainly dedicated to the maneuvers of the foredeck sails, and are not limited to releasing and trimming the sheets but also involve several fine adjustments.
Each one remains on his assigned side, without moving from one side to the other as in traditional boats. The only figure changing position during navigation is Pietro Sibello, the mainsail trimmer, who is the one positioned most aft of all, and thanks to his mobility on board is also able to control the racecourse and the position of the other boat, providing the two helmsmen with information required for final tactical choices.
Luna Rossa is the only AC75 that has opted for the configuration with two helmsmen: Jimmy Spithill on the right side and Francesco Bruni on the left. Both helmsmen also alternate in the role of flight controllers as they manage the foil control system.
The coordination of 11 people driving such a complex boat and exchanging information at 50 knots is not a simple task. A sophisticated communications system with microphones and headsets with multiple lines is used on board.
The physical effort required from the sailors on it is impressive; during the manoeuvres the acceleration reaches up to 1.5 G lateral on a boat that weighs over 11 tons (including about 1000 kg of crew weight). For this reason, often between one race and the next some crew members rotate, especially those in the most physically demanding roles.
So far, the regattas on the AC75 yachts have delivered an incredible show and the
PRADA Cup finals promise nothing less.