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. GREEN lamp: ZONE ENTRY. Status ‘On’ indicates that the leading yacht has entered a zone of two or three boat lengths from the mark. AMBER lamp: OVERLAP. Status ‘On’ indicates that the bow of the overtaking yacht is overlapping the stern of the leading yacht and there is no restriction on the leeward yacht to steer a direct course for the next mark. The leeward yacht may point higher than the direct course to the next mark causing the windward yacht to either tack or sail higher than needed to the next mark. WHITE lamp: RULE 17.1. Status ‘On’ indicates that the depth of the overlap has increased to the point where the yacht to leeward must now steer a proper course to the mark and hence cannot point higher and force the overtaking yacht to either tack or sail a higher course to the next mark. 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. The system was developed by Pilotfish Networks AB. The Formula Formula: DSP: displacement in cubic metres; L: rated length in metres; S: rated sail area in square metres; 18th man The International America's Cup Class yachts were crewed by 17 individuals. The boats had to carry what was known as the "18th man", a passenger or the equivalent weight up to 100 kg. This was a highly sought-after position, often filled by a celebrity or a representative from one of the key sponsors to the team. The end of the IACC Immediately after the conclusion of the 2007 America's Cup, Brad Butterworth officially announced on behalf of Alinghi and America's Cup Management that a new design of boat would be sailed in the next edition of the America's Cup. The feeling was that the existing IACC rule had evolved as