Thursday, August 26, 2010

Spithill, Ashby to square off against Canadians

BMW ORACLE Racing skipper Jimmy Spithill and sailing team coach Glenn Ashby finished second in the fleet racing portion of the International C Class Catamaran Championship.

Jimmy and Glenn approach a windward mark

After scoring two bullets in three races yesterday aboard Alpha, the crew had to settle for three seconds today to their main rivals, Fred Eaton and Magnus Clarke aboard Canaan. The Canadians won with the low score of 8 points, with the Aussies 2 points in arrears.

“We achieved our two goals for the day: bring the boat back in one piece and move into first place,” said Clarke, who was the “wing sitter” for BMW ORACLE Racing during the 33rd America’s Cup last February.

The two crews now square off for the International C Class Catamaran Championship Trophy in a match racing format beginning tomorrow. The first crew to score 5 points wins the 25th championship of the C Class catamaran.

Alpha, to windward, and Canaan race downwind

The showdown is an interesting pairing. Spithill and Ashby’s borrowed Alpha won the 2007 I4C trophy under the guidance of Eaton and Clarke. The Canadians’ new Canaan is a second generation development of Alpha.

On the racecourse the past two days Alpha has been every bit the equal of Canaan, if not slightly better, when sailing upwind. But downwind in a light to moderate breeze the newer cat simply out performs its elderly brethren.

Never was that more evident than today. Alpha was less than one boatlength behind Canaan at the first windward mark in the day’s first race and led in the third race, but couldn’t match Canaan’s speed downwind.

“I felt like we were in touch upwind, but the biggest difference was downwind,” said Ashby, the seven-time A Class cat world champion who’s manning the helm this week.

Glenn and Jimmy work upwind, note the curvature of the hull

“I felt like we were sailing well downwind. We mostly went the right way, but it seems like they have a little depth and speed downwind,” Ashby said.

Clarke, the Canaan crewman, concurred.

“We had good pace downwind, we were feeling good,” Clarke said. “We have a bit taller rig and Fred and I have been sailing together for five years, so we know how to maneuver the boat without having to talk about it.”

Design comparison
When it comes to limitations, C Class cats have few. The class rule has three primary dimensions, length overall (25 feet), beam (15 feet) and sail area (300 square feet). Class t-shirts bear the saying, (25’ x 14’) x (300 sq’) – rules – dogma = C.

That t-shirt was proudly worn today by Steve Killing, the Canadian yacht designer who created Alpha, Canaan and Orion (the first generation after Alpha), all owned by Eaton.

Killing didn’t hold back the information when asked to point out the differences between the two finalists.

Alpha has a moderate rocker and fairly rounded hull. Orion was an attempt to extend the top-end speed. It has less rocker, and narrow and vertically short bows. It was an attempt to make it pitch less, but when it sails into waves it slows down. It’s better in flatter water.

Canaan sails on a tight reach, note the curvature of the hull

Canaan has a half-inch more rocker than Alpha. There is more volume pushed forward in the bows, and the run aft is more gradual.

“Comparing the wings, Alpha’s is 41 feet tall and Canaan’s is 43.5 feet tall,” Killing continued. “Canaan’s wing is a higher aspect ratio with less chord length. That moves the volume up the wing more. The higher center of effort allows Canaan to fly a hull earlier than Alpha, so downwind they can dig deeper before the hull falls back in the water.

“The main tube in Canaan’s wing is built with high-modulus carbon-fiber, as is an I-beam at the front of the second element. That makes the wing 50-percent stiffer.

Canaan has come out better than we expected,” Killing summarized. “The crew on Alpha is phenomenal. I’d love to see the two crews switch boats for a test sail before this is all over.”

Alpha chases Canaan downwind

(Pictures 1 and 4 courtesy Christophe Launay; Pictures 2, 3 and 5 courtesy Trixie Wadson)