Unintended Consequences

It wasn’t supposed to happen this way. First the Kiwis and then the three other America’s Cup teams have all hit the water with daggerboards we might as well call hydrofoils, which lift their boats’ hulls clean out of the water on downwind legs, dramatically lowering resistance and increasing speed. But the AC72 rule was specifically intended to prevent that. Read my lips: No trimmable winglets.   
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UnintendedConsequences

It wasn’t supposed to happen this way. First the Kiwis and then the three other America’s Cup teams have all hit the water with daggerboards we might as well call hydrofoils, which lift their boats’ hulls clean out of the water on downwind legs, dramatically lowering resistance and increasing speed. But the AC72 rule was specifically intended to prevent that. Read my lips: No trimmable winglets. 

The key is rule 8.6: “Rudders shall not have components, such as trim tabs or moveable winglets that can be adjusted while racing.”

Foiling Moths use trimmable winglets on their rudders for pitch control, and so would the designer of any boat aiming to foil effectively—except AC72 designers, because they can’t. The rule-beating workaround uses fixed winglets on the rudders and adjustable daggerboards set at radical angles. John Kostecki, tactician for the defender, Oracle Team USA, allows that if AC72s had trimmable winglets, “They’d be a lot easier to handle and a lot safer.”

Too late for that. Once the regatta’s jury ratified the not-at-all-intuitive measurement processes used by Emirates Team New Zealand and its technology partner, Luna Rossa, permitting extra-large foils, the die was cast. Oracle’s capsize last October also provided an unwelcome but fortuitous opportunity to rethink and rebuild with larger foils. All it took was a few days last winter of sailing against “Oracle 2.0” in foiling mode to convince the Swedish challenger, Artemis Racing, that its non-foiling red machine needed a date with a chainsaw and some new daggerboards as well. 

By the end of this month, Emirates Team New Zealand and Luna Rossa expect to have relocated their one-boat campaigns to San Francisco Bay. And while Oracle and Artemis have carefully avoided setting deadlines for the launching of their second boats, at press time it appeared they too were aiming for this window—when the restrictions on sailing days are off, and the game is on.

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