"USA 17 #2" is the simple name of the catamaran that will defend the America's Cup in September. The boat completed its first test sail in San Francisco Bay at the end of April. Even on this maiden voyage, it lifted onto the leeward wing on the downwind leg with apparent ease.
Overall, the cat looks more robust, clearer and tidier than its predecessor. Great importance was obviously attached to reducing the aerodynamic resistance. The more inwardly inclined L-foils are striking. This is apparently intended to generate lift from the previously vertical wing sections. In addition, the rear spoiler has evidently grown and become more pronounced in order to stabilise the flight attitude at high speeds. The wing sail is set very low, which normally reduces the induced drag around the "lower leech".
Both helmsman James Spithill and trimmer Dirk de Ridder emphasised after the test that the boat felt very stiff. This explains the robust impression, obviously a lot of emphasis was placed on reducing twisting. The front beam is now further forwards. This twisting was one of the main problems with construction number 1 and very probably led to the spectacular capsize. When a catamaran twists, the lee float dives, the direction of travel suddenly changes downwards and the hull undercuts.
These problems should now be resolved. "The boat felt fantastic," says Spithill. "We were able to build up maximum pressure very quickly, it felt very stiff, reacted well, very quickly."
