The Revenge of the Westerly

Luna Rossa and ETNZ go one race up...

It was a big first day in the semi-finals for the Louis Vuitton Cup - Luna Rossa beat BMW Oracle by 2m 19s, and ETNZ went a race up against Desafio Espanol by 43s. But don’t let those finish deltas fool you – it was shiftier than a bloke selling 'second-hand' Rolex’s at a car boot sale, with the gradient wind blowing out of the west and off the city.

The first move came at the pre-start entry with Oracle coming in from the pin against Luna Rossa and crossing them on port. We’ve seen Oracle pull this one off half-a-dozen times (at least) in the two Round Robins, and they did it again – crossing ahead of Luna Rossa, the starboard tacker, who was entering at the committee boat. Once Oracle had got past them, they owned the right-hand side of the pre-start box and had negated the disadvantage of the port tack entry.

A huge amount of effort goes into the software used in the pre-start, but it’s easy to forget about the timing for the entry. All the work goes into modeling and predicting the boat’s approach to the start line through the different tactical maneuvers – the gybe or tack back, reaching down to the starboard tack layline for the pin, accelerating from downspeed to the line. The focus is on approaching the line, sailing upwind in the final seconds. And we’ve seen over and over how good the teams are at this, with perfect start after perfect start.

But the entry is different – the line you’re looking at is actually perpendicular to the start line, as it runs upwind from the pin. So a separate time-on-distance calculation should be done specifically for the entry, to account for the different angle of the line. The next problem is that the boat is reaching towards this line, rather than sailing upwind. This is the only time that you need to know the boat’s reaching speed, and so this job (sailing on a reach in all different wind speeds and angles so you can accurately model it for future performance) can slip to the bottom of the list and never get done.

It’s easy to end up with a fudged calculation for the entry, based on the wrong line, and using the wrong prediction of the boat’s speed. But not with Oracle, it looks like they've spent the time and money smartly, reached into a few more dark corners than everybody else, and nailed this problem. Whatever they've done, it works and they’ve practiced the entry enough to be really slick and confident. And it’s paying dividends. It was also clear that Oracle had accounted for the current that was running across the start line - although it looked like Luna Rossa could lock them out at the boat, in the end Oracle got a good start to the right, and separated well enough to live.

Then it got really tricky. There were some massive shifts coming through, tacticians and wind spotters on both boats having to back their judgment as it was a tough day to try and cover the opponent. Luna Rossa took a big lead up the beat, then lost it all on the run. And this was the crux of the match - the leeward gate. An aggressive move from Oracle, as Luna Rossa gybed to windward. With both boats now on starboard and laying the gate, Dickson put the bow up and luffed hard to hold Luna Rossa out past the port gybe layline, hoping to lead back and have the choice of gate mark.

But Luna Rossa managed to break the overlap, and once they had done that, Oracle had to come down to her proper course and gybe back towards the gate. Luna Rossa’s crew did a fantastic job of matching Oracle’s gybe, getting the headsail up and spinnaker down and holding their own overlap as they trailed Oracle back to the gate. It gave them room and control to take the left-hand mark, and that was the side of the beat that Torben Grael and Andy Horton on Luna Rossa wanted - it was the side that paid big-time up the next beat. Luna Rossa led comfortably round the final windward mark, and the big delta came from the sea breeze trying to fill at the end and dumping Oracle in a hole. Still, I wonder what odds you could have got beforehand on Oracle losing by a delta in excess of two minutes?

The other match was much more straight-forward, ETNZ won the right hand side in the pre-start, used it to get control and a good lead up the first beat and never really looked like losing it. So, Luna Rossa and ETNZ go one up in the best of five series, but there’s a long way still to go.

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Mark Chisnell ©