• Stage Two: The Prada Cup




    When the 75ft monohulls took to the air, travelling at speeds that would get you a ticket ashore, it was inevitable that the focus would be on the foils. The ability to lift a 7tonne vessel using a platform barely any bigger than a surf board is an incredible feat in itself.

    So, it was perhaps inevitable that commentators and observers would start focusing their attention on whether a particular set of foils were fast or slow, whether they were more efficient at lifting the boat out of the water or providing low drag at high speed. Their shape and their configurations has been debated at length, as has the issue of whether a particular teams foils are flat or have anhedral, where the foils are angled down to the water. There have also been discussions as to the pros and cons of foils that are straight along their length, or whether they have kinks in them, as well as the overall aspect ratios.

    Yet as far as understanding this new world goes, it is still early days and there is little in the way of consensus among observers. Meanwhile, teams are staying tight lipped as they keep their learnings to themselves.





    But, in trying to understand the issues that lie behind these and many other foil features, it’s easy to forget about the other side of the equation, the rig and sail plan. Creating sufficient power at the right time to lift the boat out of the water presents different requirements to that of delivering power at speed.

    In crude terms, the issue is similar to driving a planning powerboat. When you’re travelling slowly at displacement speeds and trying to get onto the plane, you often need to move the throttle more than you do once the boat has broken free of its displacement mode. Then, once the boat has climbed up onto it’s bow wave and is planning you ease the throttle back as the boat accelerates more freely.


    It’s a similar deal with the AC75s. Once on their foils, the drag drops significantly and the boat accelerates rapidly. This sees the apparent wind speed, (what the crew and the boat feel, as opposed to the actual wind speed if they were stationary), increase rapidly too. This means that the amount of driving force that is required is now quite different to when the AC75 was plugging along pushing water ahead of its bow trying to climb out of the water.

    The recent AC World Series provided the clearest indication so far as to how nimble teams are in this transition phase. The confines of a race course meant that we were able to compare performances for the first time.





    But the ACWS also provided the first indications as to how teams handle their machines.


    We also saw just how advanced the Defender’s sail plan is. Here, one of the clearest pieces of evidence was from the onboard camera mounted on the stern looking forward where it was easy to see just how little Emirates Team New Zealand’s sail moved from side to side on the traveller when compared to those of the Challengers.

    Unsurprisingly this was one of several indicators that drew the attention of North Sails president and two time America’s Cup helmsman Ken Read.

    “I think a sign is, is how much the travellers go up and down,” he said. “And the more a traveller moves, probably the less control you have of the rest of the sail because you're really having to dump the traveller on a bear away. We saw during one of the races the Americans were banging the traveller car into the bottom of the boat.”

    So, given their shortcomings in the light weather, it was little surprise to hear that the British team stepped a new rig shortly after the ACWS. As with all the teams, details are sparse at present, none of the Challengers wants to reveal what they are up to while their competitors have an opportunity to copy or modify their own systems.


    But this has not been the only alteration, their foils are currently different too. During the first week of training in the New Year Britannia appeared to be on the second generation of foils raising speculation that the third generation set that they had used in the ACWS are currently being tweaked.




    In the American Magic camp, the big visual difference is the new, larger bustle/skeg which is far deeper than before. Unlike that of other teams, theirs does not run all the way to the back of the boat and stops around half to two thirds back from the bow. The object of this is to create a better aerodynamic seal between the hull and the water’s surface, in other words, a better end plate that increases the aerodynamic efficiency of the rig.


    During their training sessions when they were up and running it was easy to see how much closer the team were able to keep the boat to the water’s surface and how the bow down trim that all the teams adopt, was matched by the position of the new bustle.

    According to skipper Terry Hutchinson the team had gone into the ACWS with concerns over their light weather performance. In the event they appeared to cope well in these conditions, but the addition of an extended bustle looks likely to be a modification to help develop maximum power at the lower end of the wind range.


    If there was one lesson that was clear for all, it was how punishing poor light airs performance is if your opponent is still up and flying. No one can afford to be caught out.

    So far, Luna Rossa Prada Pirelli have been harder to assess during this first week.

    During the ACWS the Italians appeared to be the quickest of the Challengers in light winds. They also appeared to be working their sail plan differently to the others. For starters they sailed the event without the stays that support the mast in the fore and aft plane, the running backstays, in an attempt to reduce windage. But that wasn’t the only difference.


    “They were very clearly setting up their mast a lot straighter than everybody else was,” said Read. “That's adjustability, that's power. So, I think teams are seeing really different setups and learning what others are doing well.”

    On the occasions when the Italian team has been out on the water the boat appears to have new aerodynamic fairings around the crew area which if nothing else, provides further evidence as to just how important aerodynamic drag is in this America’s Cup.

    But so far, Luna Rossa Prada Pirelli has been seen less in training than the other Challengers, fuelling speculation that bigger modifications to the boat may be in progress.

    Whatever is going on behind closed doors to improve performance ahead of the start of the Prada Cup, boosting the power seems to be at the heart of the changes.


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    After over three years of waiting, the wins, the losses and the points will really start to count. The PRADA Cup is set to start on January 15 with the three Challengers competing to qualify to race against the America’s Cup Defender Emirates Team New Zealand in the America’s Cup Match.

    The PRADA Cup consists of 17 racing days starting with a multiple Round Robin format where the three Challengers - Luna Rossa Prada Pirelli, New York Yacht Club American Magic and INEOS TEAM UK face off each other for four times.

    The team with the most points at the end of the Round Robins moves directly to the PRADA Cup Final, while the remaining two teams compete in a best of seven wins, head-to-head, Semi-Final between the 29th January and the 2nd February.

    The PRADA Cup Final, between the13th and the 22nd February, is a best of thirteen race series where the first team to reach seven wins will win the exquisite PRADA Cup trophy and be awarded the rights to be the Challenger for the 36th America’s Cup presented by PRADA and to race the Defender Emirates Team New Zealand.

    Therefore, to win the America’s Cup, first you have to win the PRADA Cup.

    The team with the most points at the end of the Round Robins moves directly to the PRADA Cup Final, while the remaining two teams compete in a best of seven wins, head-to-head, Semi-Final between the 29th January and the 2nd February.

    The PRADA Cup Final, between the13th and the 22nd February, is a best of thirteen race series where the first team to reach seven wins will win the exquisite PRADA Cup trophy and be awarded the rights to be the Challenger for the 36th America’s Cup presented by PRADA and to race the Defender Emirates Team New Zealand.

    Therefore, to win the America’s Cup, first you have to win the PRADA Cup.

    The excitement after the PRADA America’s Cup World Series Auckland is tangible among the New Zealand public. The match-races were fiercely contested and attracted plenty of supporters interests both ashore and on the water. The racing in December was crucially important to all of the teams and has revealed a great deal about their relative strengths and weaknesses. Each of the Challengers have been working relentlessly during the Christmas break to make changes and improvements to their AC75s and there is great anticipation to see them racing again now that the stakes are much higher.

    Two races per day are scheduled during the PRADA Cup, the race window between 3:00 PM- 5:00pm NZT with the exception of the Final’s races which will be between 4:00 PM- 6:00pm NZT.

    The racecourse will be a windward-leeward configuration outlined by boundaries with an upwind start and its length (approximately between 1.1 to 2.2 nm) will depend upon the exact location of the course and prevailing weather conditions. The permitted wind range is between 6.5 and 21 knots for the Round Robins and the Semi-finals and between 6.5 and 23 knots for the PRADA Cup Final.

    The course on which the teams will sail, will be decided every racing day by the Race Management and detailed information for on water spectator will be available on americascup.com

    THE CHALLENGERS




    Luna Rossa Prada Pirelli
    Challenger of Record

    On the 26th of June 2017, immediately after the final race of the 35th America’s Cup, the Royal New Zealand Yacht Squadron received and accepted a Notice of Challenge from Circolo della Vela Sicilia, thus its team Luna Rossa Prada Pirelli Team officially became the Challenger of Record of the 36th America’s Cup. The team, established in 1997 by Patrizio Bertelli, CEO of the PRADA Group, is now at their sixth attempt to win the America’s Cup and is led by two times Cup winner Skipper and Team Director Max Sirena.






    New York Yacht Club American Magic
    Challenger

    Formed in October 2017 by Bella Mente Racing, Quantum Racing and the New York Yacht Club, American Magic represents a joint vision to win the America’s Cup.
    The team brings together two highly successful racing programs with one of the foremost yacht clubs in the world. The name, American Magic, is a nod to the New York Yacht Club’s storied America’s Cup history; a combination of the boat the trophy is named for, and the first boat to defend it.




    INEOS TEAM UK
    Challenger

    INEOS TEAM UK was formed in 2018 to bring the America’s Cup home to Britain and will race for Royal Yacht Squadron Racing that is regarded as one of the most prestigious yacht clubs in the world. Before relocating to New Zealand, the team was based in Old Portsmouth, led and backed by INEOS Founder and Chairman, Jim Ratcliffe. Sir Ben Ainslie, a previous America’s Cup winner (AC34) and the most successful Olympic sailor of all time is the Team Principal and Skipper.
    This article was originally published in forum thread: Stage Two: The Prada Cup started by Photoboy View original post