{"id":66633,"date":"2018-03-07T00:11:13","date_gmt":"2018-03-07T05:11:13","guid":{"rendered":"https:\/\/www.sailingworld.com\/?p=66633"},"modified":"2023-05-06T21:45:17","modified_gmt":"2023-05-07T01:45:17","slug":"the-americas-cup-75","status":"publish","type":"post","link":"https:\/\/www.sailingworld.com\/racing\/the-americas-cup-75\/","title":{"rendered":"The America’s Cup 75"},"content":{"rendered":"\n
\n\n\t\t\t
\n\t\t\t\t\t\"AC75\" <\/div>\n\t\t\t\n\t\t\t\n
\n Some components of the AC75 will be one-design, such as elements of the wing sail, foils and foil-control systems. According to BMQR\u2019s Terry Hutchinson, 600 mm of the T-foil will be left open, allowing teams to plug-and-play foil tips for different conditions.<\/span>\n Photo: Botin Partners<\/span>\n\n\t\t\t\t <\/figcaption>\n <\/section>\n\t\t\n\n\n\n

It’s been name-called the three-legged gecko, the freak and countless others, but designers and engineers tasked with delivering this first generation of the AC75<\/a> proposed by the America’s Cup defender and challenger of record use one word to describe it: freedom.<\/p>\n\n\n\n\n

\u201cThe platform is known,\u201d says Adolfo \u00adCarrau, with the design firm Botin Partners. Botin is designing for the American challenger Bella Mente Quantum Racing. \u201cThe demands are similar to the multihull [used for the 34th America\u2019s Cup], and at the end of the day, it\u2019s a foiling boat. A lot of work was done by teams in the last campaign, work to improve the tools required to design foils, and most of the work these guys were doing continues. But still, there is not a lot of tradition in this boat.\u201d<\/p>\n\n\n\n\n

The only distant tradition to the Cup, of course, is the monohull, a different take on which was presented by Emirates Team New Zealand \u2014 the clever defender that almost dethroned Oracle Team USA in San\u00a0Francisco in 2013, and then did so in Bermuda in 2017. With both New Zealand challenges, the Kiwis were steps ahead with their foiling initiatives, and their undeniable foiling-technology prowess is their strength. It comes as no surprise, therefore, that the AC75 is essentially a big, lightweight \u00adsurfboard meant to fly.<\/p>\n\n\n\n\n

With the AC multihulls came plenty of righting moments from the platform. With the AC75, that righting moment will come from the foils. As awkward and bizarre as the concept might appear to traditionalists, simulations conducted at Botin while they await the class rules confirm the AC75 concept will work.<\/p>\n\n\n\n\n

\u201cOur in-house simulations confirm what they were predicting,\u201d says Carrau. \u201cWhich is it should be able to foil in over 9 knots of true wind \u2014 both upwind and downwind.\u201d<\/p>\n\n\n\n\n

It\u2019s an interesting concept that doesn\u2019t exist at the moment, he adds, so the design team must rely heavily on dynamic simulations in the upcoming year. \u201cIt\u2019s going to be an interesting Cup cycle because of this new concept,\u201d he says. \u201cEveryone will be relying on their technology to design their boat.\u201d<\/p>\n\n\n\n\n

In other words, the boats will be designed by the computer. Only when they have something tangible can they start applying experience and sailor-driven enhancements. \u201cIt\u2019s hard for the sailors and designers at this stage to anticipate how the boat will behave in every condition,\u201d he says. \u201cIt\u2019s so completely new.\u201d<\/p>\n\n\n\n\n

Over time, Carrau and his peers have been limited by processing power of the simulators. Creating from scratch at this level is about big data and speed, he says. Emirates Team New Zealand doubled down its time and money on a good simulator in advance of the 34th Cup cycle \u2014 more so, he says, than any other team.<\/p>\n\n\n\n\n

Unique as the AC75 might appear to the wider public, the concept is not all that foreign to sailors. In a sense, it\u2019s like a giant International Moth, relying on the active foil to produce most of the vertical lift and side force required to lift the hull free of the ocean\u2019s grip. A rudder elevator corrects pitch angle and contributes to vertical lift as well; early simulations confirm as much. Without a detailed version of the AC75 rule, however, plenty of guesswork remains: the dimensions of the foils and the freedom of where all the associated bits and pieces can be positioned.<\/p>\n\n\n\n\n

The other significant unknown for Botin\u2019s early efforts is the AC75\u2019s rig concept and geometry. What it will ultimately be \u2014 soft or hard sail, or a combination of both \u2014 is essential intelligence. The rigid wing of the AC50s delivered a lot of power for foiling maneuvers, power that would be lost with a soft sail as it passes through the wind.<\/p>\n\n\n\n\n

\n\n\t\t\t
\n\t\t\t\t\t\"AC75 <\/div>\n\t\t\t\n\t\t\t\n
\n The AC75 is a blend of known and unknown concepts, says Botin Partner\u2019s Adolfo Carrau, similar to a Moth, but the ballasted foils provide righting moment and the ability to right from a capsize.<\/span>\n Photo: Emirates Team New Zealand<\/span>\n\n\t\t\t\t <\/figcaption>\n <\/section>\n\t\t\n\n\n\n

The AC75\u2019s ultimate appearance will be dictated by the intended nature of the racing format itself. In the pre-start, for example, the traditional dial-ups will be a big area to try to understand and simulate with a boat lacking a keel and bulb. \u201cThat\u2019s where part of the rule development is happening now \u2014 the amount of ballast on those struts,\u201d says Carrau. \u201cEnsuring there is enough initial stability to do pre-start maneuvers and dial-ups without capsizing the boat.\u201d<\/p>\n\n\n\n\n

There are more unknowns out of the gate, which appeals to Carrau and his colleagues. \u201cIt\u2019s going to be challenging being the first on these new boats, with very compressed timelines to build the boat,\u201d he says.<\/p>\n\n\n\n\n

By compressed, he means Boat No.\u00a01 should be in the water by late March 2019. Seventy-five feet is a big boat, and a \u00adcomplex one at that.<\/p>\n\n\n\n\n

While the defender, by nature of \u00addictating the terms of the regatta in Auckland in March 2021 does have a leg up (or maybe that\u2019s a foil up), the relatively clean slate of the AC75 is an opportunity for \u00adothers. Among the challengers, he says, the playing field is level. The goal is to outsmart the defender at its own game.<\/p>\n\n\n\n\n

\u201cRight now, they\u2019re a foiling team, so they played that well\u201d in designing the AC75, he says. The boat reflects where Team New Zealand feels most confident \u2014 in a foiling boat and relying on a simulator to make decisions.<\/p>\n\n\n\n\n

\u201cThe concept and physics of the boat are not the most difficult part,\u201d he adds. \u201cMechanically it\u2019s going to be difficult to engineer all the systems, and everything depends on how much freedom they allow in the rule for the flight-control systems and so on.\u201d<\/p>\n\n\n\n\n

Of note are the systems that will be required to manage the ballasted foils. Whereas the AC50\u2019s foils were smash-drop entry, the AC75\u2019s foils will essentially enter the water at an angle, which Carrau says will help with ventilation issues that prevent foiling tacks and jibes. At the same time, he cautions, with straight-line sailing, the leeward foil tip must remain submerged to prevent ventilation. From a handling point of view, it will be important to get the \u00adoptimum foil depth to the water\u2019s surface.<\/p>\n\n\n\n\n

Experience with multihull \u00adengineering before the previous Cup led to reliable structures, but with this boat, says \u00adCarrau, there is no true starting point. \u201cWe have to reimagine the new load cases and the worst-case scenarios that will happen with this boat,\u201d he says, \u201cand then build in the proper safety factor for each component, for an unknown boat. That\u2019s the biggest short-term challenge.\u201d<\/p>\n\n\n\n\n

The challenge now is the freedom in the rule and delving deep into the simulator for an opportunity and a better idea. \u201cThat\u2019s the game,\u201d he says, \u201cand that\u2019s how we are \u00adpreparing ourselves.\u201d<\/p>\n\n","protected":false},"excerpt":{"rendered":"

The race is on for America\u2019s Cup designers to understand the new platform.<\/p>\n","protected":false},"author":1,"featured_media":30623,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"BS_author_type":"BS_author_is_guest","BS_guest_author_name":"Dave Reed","BS_guest_author_url":"","hydra_display_date":"20180307","hydra_display_updated":false,"_yoast_wpseo_primary_category":"159","_yoast_wpseo_metadesc":"Designer Adolfo Carrau explains the intricacies of the AC75.","_yoast_wpseo_title":"The America's Cup 75 %%sep%% %%sitename%%","_yoast_wpseo_meta-robots-noindex":"","arc_story_id":"TZARCDEKV3R6PLRFXCBQFVFDTE","arc_website_url":"americas-cup-75\/","custom_permalink":"","arc_subtype":"right-sidebar","arc_exclude_from_feeds":false,"sponsored":false,"sponsored_label":"Sponsored Content","sponsored_display_label":false,"sponsored_image":0,"post_right_rail":true,"post_right_rail_ad_1":true,"post_right_rail_ad_2":true,"post_right_rail_ad_3":false,"post_right_rail_ad_4":false,"post_right_rail_recirc":true,"fixed_anchor_ad":true,"post_top_ad":true,"post_off_ramp":true,"post_taboola":false,"labels":false,"apple_news_api_created_at":"","apple_news_api_id":"","apple_news_api_modified_at":"","apple_news_api_revision":"","apple_news_api_share_url":"","apple_news_coverimage":0,"apple_news_coverimage_caption":"","apple_news_is_hidden":false,"apple_news_is_paid":false,"apple_news_is_preview":false,"apple_news_is_sponsored":false,"apple_news_maturity_rating":"","apple_news_metadata":"\"\"","apple_news_pullquote":"","apple_news_pullquote_position":"","apple_news_slug":"","apple_news_sections":"\"\"","apple_news_suppress_video_url":false,"apple_news_use_image_component":false,"footnotes":""},"categories":[159],"tags":[770,593,178],"class_list":["post-66633","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-racing","tag-ac75","tag-quantum-racing","tag-sailboat-racing"],"acf":[],"apple_news_notices":[],"_links":{"self":[{"href":"https:\/\/www.sailingworld.com\/wp-json\/wp\/v2\/posts\/66633","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.sailingworld.com\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.sailingworld.com\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.sailingworld.com\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.sailingworld.com\/wp-json\/wp\/v2\/comments?post=66633"}],"version-history":[{"count":0,"href":"https:\/\/www.sailingworld.com\/wp-json\/wp\/v2\/posts\/66633\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.sailingworld.com\/wp-json\/wp\/v2\/media\/30623"}],"wp:attachment":[{"href":"https:\/\/www.sailingworld.com\/wp-json\/wp\/v2\/media?parent=66633"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.sailingworld.com\/wp-json\/wp\/v2\/categories?post=66633"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.sailingworld.com\/wp-json\/wp\/v2\/tags?post=66633"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}