Cool Cat
Cool Cat
The little sister of the still-to-come AC72 turned all heads during its 14-day dress rehearsal on Auckland’s Waitemata Harbour. "Tech Review" from our March 2011 issue.
On time and as promised, the first AC 45 catamaran was handed over to America’s Cup Race Management in Auckland, New Zealand, on January 31 following two weeks of builder’s trials. Assembled, rigged, and commissioned just four days afer leaving in pieces from Larry Ellison’s Core Builders in Warkworth, north of Auckland, the sleek wing-sailed 45-footer turned in a scintillating performance on its first outing in 10 knots and shone in gusty 25-knot conditions the next day.
America’s Cup winning helmsman James Spithill delivered his upbeat verdict at the end of the first day’s trials, declaring: “Everyone who sails this boat will step off with a smile on their face, I guarantee it!”
Highlighting the wing’s versatility and ease-of-use, Spithill and his test crew from Oracle Racing sailed the cat off the dock on its maiden voyage, negotiating the confined channels of the Viaduct Basin with ease, and returned in the same relaxed manner.
Ten days afer their first sail, Spithill’s crew parked the boat overnight for the first time, leaving it on a prototype mooring inside the Viaduct Harbour. The buoy was an inflatable tetrahedron race mark, mostly filled with fresh water to dampen its movements.
Attached by a bridle, with boards up and the rudders toed inwards almost 90 degrees, the boat lay docilely, gently swinging in the breeze like a weathervane.
During February, Oracle and the confirmed challengers will each spend a week trialing the first boat before taking delivery of their own boats starting in March. Initially four boats will be available. Additional boats will roll out every two weeks. The first production run is 10 boats.
Power, grace, elegance, and relentless attention to detail all come to mind as one looks at the cat, ashore and afloat. The Oracle Design Team wanted a boat that was light, robust, easy to sail, and capable of delivering excellent performance across a range of conditions from 5 to 30 knots. The boat carries a crew of five, plus one guest.
Mike Drummond, a veteran Cup designer from the Oracle Racing Design Team, summed up the result. “You’re always hoping when you use CAD and CNC machines that everything will fit together like it is supposed to in the brochure, and yet sometimes it doesn’t. In this case everything fit, everything slotted together physically. Everything came together project-wise and time-wise and obviously the structural estimations and designs were on the money and the boat went sailing right away at full potential.”
The cat is reminiscent of a smaller, winged Alinghi catamaran. The boat features the same style of central, braced spine of the unsuccessful Swiss defender of the 33rd America’s Cup in 2010. The wing sits on a ball smaller than a standard trailer hitch, and is held in tension by the forestay and shrouds. The braced spine permits headstay loads of up to 2.5 tons. A load cell warns when the permissible maximum is reached.
Dirk de Ridder, who was the wing trimmer on BMW Oracle Racing’s victorious USA 17, is part of the team working on the new boat. “We’ve made an effort to keep it simple but still have it as a proper raceboat,” he says. “Things like the infinitely variable jib traveler sheet systems mean that the teams can use it as a tool as they develop their AC72s.”
The AC45 invites an invariable comparison to Extreme 40 catamarans and the design team gave serious consideration to modifying existing Extreme 40s to carry a wing. Ultimately they chose to go for a new design.
