International America's Cup Class

The International Americas Cup Class was a class of racing yacht that was developed for the America's Cup between 1992 and 2007. These yachts, while not identical, were all designed to the same formula to offer designers the freedom to experiment whilst keeping the boats sufficiently comparable to race in real time. The class was established for the 1992 America's Cup because of perceived shortcomings of the 12-metre class, which had been used in the America's Cup since 1958.

In addition to the America's Cup, IACC yachts were raced in other regattas, including the IACC worlds.

IACC sail numbers were issued according to the date when the ACM measurement committee decided that the hull has reached a certain stage of completion. The number came in two parts: the flag state (represented by a three letter prefix) and the hull number. The country code changed as the hull was transferred from flag state to flag state. Only one boat had a sail number issued twice as in the case of RUS-62 which was a new boat based on the heavily modified hull of RUS-24 and re-registered as RUS-62.

Version 5.0 of the International America's Cup Class Rule was issued on December 15, 2003. Copyright is held jointly by the Defender Alinghi and the 'Challenger of Record' BMW Oracle Racing.

Typical parameters of an IACC yacht were:

The 2007 America’s Cup saw the introduction of the ‘’Umpire Signaling System’’ (USS) which allowed the Umpires to notify the two boats regarding their position in relation to each other when overtaking and their position relating to a mark of the course when in close proximity of the mark.

On both the defender and the challenger there was a display unit with three LED lights coloured green, amber and white respectively.

The rules of racing define what tactics/maneuvers are permissible when a yacht nears a mark and also when a trailing yacht starts to overtake the boat in front. The purpose of the USS is to remove doubt and associated protests caused by competitors having differing opinions of either their positions relative to each other or their distance from marks and then performing tactical maneuvers prohibited by the racing rules.

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