Iain Murray explains why Wild Oats XI has been the focus of so much attention and why the race will be a needle match between the big guns

Given the current weather forecast, the 2013/14 Sydney Hobart Race is unlikely to set any new records. But the annual sprint across to Tasmania promises to be one of the most intriguing in years as some of the world’s top high performance boats battle to gain the upper hand as the complex weather scenarios play out.

Among the favourites, Bob Oatley’s Wild Oats XI is has been one of the most talked about this year. Winner of the 2012/13 event in which she set a new course record, beating her own previous record, the Reichel Pugh design has again been turning heads, this time for her extreme underwater configuration. Nicknamed the Swiss army knife for the proliferation of dagger boards and foils that can be deployed. She’s also particularly remarkable given that she was originally launched in 2005 and has taken part in eight previous races of which she has claimed line honours six times and holds the current record of 1 day, 18 hours, 23 minutes 12 seconds. She is also one of only two boats to have taken the treble crown twice, consisting overall, handicap honours and race record.

A victory on handicap this time would allow Wild Oats XI to also equal the race record of most overall wins, currently shared by Freya and Love War, with three each.

To find out more about why Oatley’s boat has been the focus of so much attention I spoke to navigator and long term crew member Iain Murray, (yes, he of America’s Cup fame), who explained what the latest developments have been and why this 100ft LOA canting keel slender hulled machine has now sprouted another moveable foil.

“Originally the boat was fitted with a forward rudder in her CBTF configuration but this was replaced by a pair of dagger boards,” said Murray. “Over the years we have struggled to sail upwind in the light so a small canard was fitted forward to help with this and to reduce the amount of lee helm that the boat develops. We tend to use this up to 10-11 knots of boat speed.

“The latest board to be fitted though is the horizontal DSS [Dynamic Stability System] which helps to generate more righting moment in certain conditions.”

The DSS is a horizontal board fitted below the waterline that slides through the hull from tack to tack. Set at a fixed angle of attack the board is said to generate 7 tonnes of lift at around 22-25 knots of boat speed while at the same time reducing the displacement of the boat by around 22 percent. The additional righting moment is impressive given the 3 tonnes of water ballast that would be required to achieve a similar increase but that would also add to the displacement of the boat.

“We haven’t sailed with the board very much yet, ” continued Murray, “in fact around half an hour. But from the testing and analysis along with what we have felt so far, the board also seems to trim the bow up a bit.”

The increased righting moment, 50,000kg.m to 65,000kg.m was so significant that Wild Oats XI had to have a new mast to cope with the additional load. Here, another big improvement has been made with a stronger spar that is also 200kg lighter with a centre of gravity that has been lowered in the process. An impressive win/win made possible thanks largely to the use of a higher modulus carbon fibre. And the weight saving didn’t stop there as the team have fitted a boom which is 169kg lighter.

“We have re evaluated the engineering on this boat several times but I think this is probably the furthest we could go with this boat,” he said. “She’s fully optimised now.”

Knowing when and how much to deploy her various swinging, lifting and extending boards and foils will be an art in itself.

But while the fleet’s focus is on Wild Oats XI, Murray is quick to stress that the competition is stiffer than ever this year.

“Wild Thing has undergone some major changes and is a serious contender on handicap. Then there’s Ragamuffin skippered by Ian Walker and his Volvo crew along with Loyal, the old Speedboat that has undergone some major changes and in my opinion is the favourite for the race.

“Then you’ve got Beau Geste which could be an absolute screamer and Matt Allen’s new Carkeek 60 Ichi Bahn.”

But screeching around the course might be tricky given this year’s forecast conditions which are as complex as the fleet that is trying to make sense of them.

The 10-15 knot south-southeasterly’s forecast for the race start on Boxing Day will increase as the fleet makes their way south – and by late Saturday, strong to gale force westerly’s will challenge the smaller boats that will likely still be racing.