“In the America’s Cup, whoever goes the fastest wins in the end,” so Luna Rossa’s owner Patrizio Bertelli ruled in an interview with New Zealand TV.
But if, as in the case of this 36th America’s Cup final, the two boats have very similar performances, who wins? Certainly the skill of the crew matters, but not only that. It is the small differences that make the final result. Experts from Tip & Shaft, the expert media for sail racing, investigated thoroughly.
What emerged was the super partes technical analysis that everyone was waiting for.
Here is what French designer Dimitri Despierres, who is part of the U.S. team at American Magic, one who knows a lot about these America’s Cup boats, analyzed.
And finally, hear how our super-expert in physics applied to America’s Cup boats Elio Somaschini analyzes the lesser Luna Rossa drift, which causes her to travel less distance than her opponent.
That’s why those who start in the lead then win
Almost everyone thought before the finals that Team New Zealand would find that little bit of extra speed. But instead it is a real competition with two boats that have very similar speeds, with on the one hand an Italian crew losing a little less on the turns than the Kiwis, while on the other hand, the latter have a slight advantage in stern swings, while upwind, the performance sine very similar.
All of this means that the boat that manages to get ahead at the start or first crossing is able to keep its opponent in check. It is very difficult to overtake on this course (also due to the presence of the very narrow boundaries outside of which you cannot sail), where the wind is in fact not very changeable at the moment, remaining quite stable in strength and direction.
Why Luna Rossa gains in tacking
It is amazing to see how close the boats are in terms of speed, since they have such different foils, and this is in any condition. We thought Team New Zealand would slaughter Luna Rossa in moderate conditions and that Luna Rossa would have the advantage in lighter conditions, but surprisingly that is not the case.
The difference really comes down to area: for New Zealanders, it is about 10-15% less. On paper, they say that as soon as you start flying, a boat with a smaller surface area has less drag, so the speed difference we thought existed between the two boats was largely due to this.
But what explains the gains made by the Italians during the board changes are due to the fact that the lower part of the foil arm, which is not single-patterned (unlike the upper part), is symmetrical for Prada and asymmetrical for Team New Zealand. The consequence is that there is a lull during an edge change, which sees the Kiwis lose 8-10 meters with each turn. This is what we saw on the water in each case. Other than that, the only other major difference is in the way the boat is steered.
Tighten more upwind, so does Luna Rossa
Generally you can see that Peter Burling, helmsman of New Zealand, has a boat that reflects the way he sails, that is, he sails a little lower and faster, while Luna Rossa sails a little slower but higher. Simply put, the New Zealanders (as sailor Giulio Desiderato explained well in an episode of The Cup Newspaper) have the philosophy of “walking the boat” at all costs, while the Italians “splint” more. This actually helps them, because on the first tack to the limit, this allows Prada to change tack and regain control of the race.
How does Luna Rossa not drift
Few have detected it, but drift (the lateral displacement while sailing) is also there in these flying boats. It was taken care of by physics professor sailor Elio Somaschini, the great expert host of the “Cup Journal” episodes, who explained it in the video HERE.
Somaschini in a simple but scientific way, explained why one of Luna Rossa’s secret weapons is the smaller drift compared to New Zealand. And so why, while sometimes being less fast than the New Zealanders, the Italian boat travels less distance. Thus canceling the absolute performance deficit. To find out why…just swerve a little.
Tonight there was no racing, no wind, no race. But we are there. And what super guests! We look forward to seeing you at 1 p.m. at the Cup Newspaper!
Guests of the episode, along with our own Bacci Del Buono and Mauro Giuffrè, will be Olympic sailor, sailmaker and CEO of Neo Yachts Paolo Semeraro; young flying sailor Clelia Sessa, a Moth class specialist; numbers wizard Federico Albano; and editor-in-chief of the Giornale della Vela Eugenio Ruocco.
Plus a surprise special guest: maestro Gianni Mazza, conductor, composer, keyboardist and TV personality. Most importantly, unsuspected and passionate yachtsman.
