Update
Lending a little more perspective to those first Whitbread Round the World Races… this is Chay Blyth’s Alan Gurney-designed Maxi ketch Great Britain II in the Southern Ocean in the first of her five (sic) round-the-world races in 1973. She completed a 6th race in 1994 but not as a registered entry. GB II finished that first race 6th overall, Ramón Carlin’s Swan 65 ketch Sayula II taking the podium. One place behind Blyth in 7th was the Ocean 71 Second Life skippered by Roddy Ainslie – the late father of another fine British sailor
AC75 V2 – SOME IMPORTANT DIFFERENCES – Jack Griffin For the first time since 2007 the next America’s Cup will be sailed in the same class of yachts as the previous edition. The AC75s surprised us by providing entertaining match racing. Version 2 of the class will bring improvements. The boats will be lighter. Combine the weight saving with the new longer span for the foil wings and the boats should take off in less wind. Control systems will remain hidden, but they will be more efficient
– a host of detailed restrictions will be replaced by a single principle: no automated systems. Formerly forbidden, feedback and coupling in the controls will be allowed, as long as all controls require humans to initiate things. Running backstays are gone, together with the weight of their winches. The winches for jib trim are gone too, since the jibs will be self-tacking. The Code 0 was never used in racing. It is gone from the new class rule, saving another 90kg – the old rule required ballast to be carried if the Code 0 was not onboard. Ballast has also been removed from the foils – another weight saving, and the idea of an AC75 being self-righting has disappeared. The hull of the AC75 is 68ft long. With no Code 0 there is no
need for a bowsprit, which made the 2021 boats 75ft long. The boats will keep their length in 2024 – a one-design component to carry wind instruments will replace the bowsprit. The new class rule addresses a few things that were off-target
in the original AC75 concept. Forbidding cyclors was supposed to make the images from the boats more interesting. We were sup- posed to see the crew work. The class rule forbade self-tacking jibs and required that one crew cast off the jib sheet from a winch during a tack, after another sailor had loaded the new active sheet on another winch. The Code 0 would be hoisted for downwind legs. It would be furled and unfurled during gybes and dropped after rounding the leeward gate. But once the importance of reducing parasitic drag became clear
the sailors, winches and grinding pedestals were all hidden from the airflow and from the view of the audience. Likewise, we never
14 SEAHORSE
saw any sail changes – the Code 0 was never used in a race. A major factor in weight reduction is crew reduction – from 11
to eight. Four crew to power the sail-trim systems and four to sail the boat. The power will almost certainly come from cyclors, forbidden in 2021 but now allowed by the class rule. Less energy will be needed from the cyclors – no need to power
winches for the jib or the runners. We may see more teams with two helmsmen, as Luna Rossa had in Auckland in 2021. A team could opt for one helmsman and one flight controller, or two helms- men, each handling flight control when the other is steering. A dedicated mainsail trimmer seems like a must. That distribution of duties would leave one sailor free to be tactician. Control systems remain out of sight but remain hugely important.
The 2021 version of the class rule used a lot of detailed restrictions to prevent automated control systems. The new rule eliminates most of these restrictions by simply saying that automated control systems are not allowed. This seems a bit like Yahweh giving Moses 10 commandments
to replace the hundreds of rules in the Torah. The mainsail and jib may now be coupled, so that adjusting the
mainsheet traveller can automatically adjust the jib sheeting angle. Mainsheet trim may now have both a low-purchase system for fast sheeting and a high purchase for fine adjustment, formerly forbidden. Active mainsail controls are now limited to the lower mast zone – up to 1.5m above the mast step. The first version of the rule included an upper zone with active controls. By making the boats about one ton lighter and increasing foil
wingspan from 4m to 4.5m they should be able to take off when the wind is at the lower limit, likely to remain at 6.5kt. That windspeed was enough for the 2021 boats to stay on their foils but not enough to take off from displacement mode. Race 8 of the Match demonstrated the problem. On the first
downwind leg Team New Zealand fell off their foils after a gybe that took them into a light patch. They needed four minutes to find enough wind to get back up flying. By that time Luna Rossa had
DAVID LESLIE/PPL
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