America's Cup Rialto: January 5 - Defenders play the FR0 card
by Richard Gladwell, Sail-World NZ 5 Jan 2021 22:13 NZDT
5 January 2021
Emirates Team NZ and American Magic - Auckland - January 5, 2021 - 36 America's Cup © Richard Gladwell / Sail-World.com
As predicted in our last Rialto, the biggest takeout from the America's Cup World Series and the Xmas Cup, was the huge benefits to be gained by efficient foiling in light breezes.
Today Emirates Team New Zealand were testing their FR0, while the Challengers seem to be of the view/hope that the super-size jib will not be required. Or that no teams will have given it away as being too hard/or that there are other priorities
In the final race of the America's Cup World Series, the Kiwis managed to turn an 800metre deficit into a 300 metre lead on the 2,500 metre second downwind leg.
It was a similar but different story the following day, when Peter Burling and friends sailed the final leg at displacement speed and missed finishing the race by a very narrow margin.
There are two issues in breezes at the lighter end of the scale for the AC75, the first is to generate the speed and lift to get foiling. The second is to maximise the VMG (Velocity Made Good), or effective speed in the direction of the mark - or efficient foiling.
The use of the Code Zero or FR0 (Fractional Rig Code Zero), flying from the bowsprit could be a solution to both issues - providing the grunt to get the AC75 foiling and then to tow the boat downwind at a faster VMG.
The FR0 is effectively a flat cut big jib, presenting significantly more sail area than the J1 or full hoist jib.
[As well as the FR0, AC75's are allowed two sizes of jib - one with a luff length of up to 20 metres, and the second with a luff length of less than 18 metres. Maximum cross width measurements control the size/area of each sail of the three sails - J1, J2 and FR0. A total of 29 jibs are permitted (which includes the FR0). Any sail that is carried but not set must remain on deck.]
Clearly Emirates Team New Zealand are working on the premise that the upsides of the extra sail area, both up and downwind are worth investigating further.
They will have tested this in their simulator, probably running data from the two races above, and then factoring in the expected performance gain from the FR0.
There are three tradeoffs.
First they have to work out how to tack with the sail, if they are using it to sail to windward. Last year we watched ETNZ using the sail upwind. The tacking was not pretty, but the gain with the increased sail area is that it should be sufficient to get the boat foiling earlier.
Second, if they are going to carry the FR0, giving them a good option if the wind lightens after the start, then that creates more windage, or aero-drag. Some way of bagging/covering the sail - so they need to find some way of bagging the sail - so that drag is reduced. The shape of the Emirates Team New Zealand deck with its channels either side may give some options that weren't there with the more flush decked Te Aihe.
Finally they have to find a way to furl and unfurl the sail without putting a support crew on board to do the job as at present. All AC75's are fitted with small furlers something more substantial is required (probably larger and adding more aero-drag). Or they live with having the sail permanently rigged for the whole race.
Of course the Defender, not having to be ready to sail until the America's Cup starts on March 6 - just under 60days away - has the time to invest into a FR0 program.
The Challengers who have to be ready to sail in the Prada Cup - in nine days time - have higher priorities than sorting out the intricacies of the FR0.
The suggestion, from those in the media who like writing "yarns" on the topic of AC75's not being able to foil in light winds, is to raise the lower wind limit.
Most yarns are based on a fact or two accompanied with a large helping of imagination. Raising the lower wind limit sounds like a great idea, but has the unintended consequence that more races will fail to start, because the wind hasn't kicked in at the required level. At best that leads to delays in the start of televised racing, and usually means no racing at all.
Most of those spinning the lower wind limit yarn, forget that in 2000 and 2003 Auckland became the poster child for wind limit delayed racing - or complete abandonment - to the chagrin of all involved.
The then City of Sails reputation was challenged four years later, in Valencia, when the first four days of the 2007 Louis Vuitton Cup were lost due to light variable winds below the wind limit. To keep themselves entertained the German crew hitched a wakeboard to the jib trimming winches - at least the grinders got a workout. The wind limits system to be used in Auckland is very similar to that used in Bermuda - where it was fair and worked very well.
Another Xmas yarn centred around the fact that previously unscheduled additional Practice racing would not take place - and that would be to the detriment of the Defender Emirates Team NZ. While the Regatta Director was quite amenable to having more practice race days, the teams with a tightly programmed schedule were always unlikely to agree - and any agreement would need to be unanimous.
Re-sailing the Xmas Cup was also a great idea. But to do that a reserve day needed to have been scheduled. It is hard to believe that anyone who saw the five days of Practice Racing prior to the ACWS could believe that ETNZ was a beneficiary - with jumped starts, boats pulling out after half a leg and other nonsense typical of most pre-regatta racing.
Changing the America's Cup always seems to find a ready ear or two, at this stage of an America's Cup regatta in Auckland. Back in 2003 there were ideas aplenty coming from a San Francisco based group - which got the predictable response that "if you want to change the Cup, then win it first and make all the changes you like".
Of course when a yacht club from San Francisco did win the Cup in 2010, it didn't broaden the appeal of the event to all those who sail monohulls and like tactical racing. Instead, those who had the power to bring about change, and reduce cost, put a 72ft foiling wingsailed catamaran into the event. They went down a similar path for the 2017 America's Cup starting with a 62ft foiling wingsailed catamaran, and then nine months after entries opened changed the class to a one-design 50fter.
The yarn about shifting to a big displacement monohull for the Cup - falls over on the question of whether the boat would have a canting keel or not. Almost all supermaxis around that length have canting keels, which are tilted by using the yachts engine to run various canting systems. Follow a supermaxi race and it is apparent that most sheet their sails with power winches, and cant their keels without human power. Are they any less of a boat for that - of course not - it means they can be driven far harder, and they are great to watch in a moderate to fresh breeze.
The 83ft 25tonne, International America's Cup Class which served the Cup well from 1992 to 2007 didn't have a canting keel either. While it was a great match racing boat, could get cleaned up by most race boats 30ft shorter. Everyone knows that the biggest expense in an America's Cup campaign is on people, and even if the Cup was raced in Optimists, the teams would still be able to find a way of spending $100million on a three year program. New thinking is great, but needs a foundation in reality.
America's Cup impresario Bruno Trouble nailed the argument.
Way too much comment on the current America's Cup comes from those who have not seen an AC75 sail - except on video. Be assured the AC75 is a way better boat than its critics would have you believe.
But back to this day in the America's Cup.
The lighter breeze of the morning gave way to a lovely sea breeze in the afternoon.
Emirates Team New Zealand and American Magic trained - in an uncoordinated manner - off Auckland's North Shore. Sailing what appeared to be windward leewards - not that much else can be done in that area, in an onshore breeze.