AC75

The AC75 (America's Cup 75) is a racing yacht used in the 2021 America's Cup match and planned to be used for the 37th America's Cup and 38th America's Cup matches. The 23 m (75 ft) monohulls feature wing-like sailing hydrofoils mounted under the hull, a soft wingsail,[1] and no keel.[2]

AC75
Ineos Team UK AC75
Development
Year2017 –
No. built8 launched
Roleinshore racing
NameAC75
Boat
Crew11 + 1 optional guest
Displacement6,450 kg (14,220 lb) lightship
7,600 kg (16,800 lb) loaded
Draft5.00 m (16 ft)
Hull
TypeFoiling Monohull
Constructioncarbonfiber
LOA22.86 m (75 ft)
LOH20.70 m (68 ft)
Beam5.00 m (16 ft)
Hull appendages
Generaltopside-mounted ballasted canting T-wing foils
Ballastset in foils
Rudder(s)centerline T-wing rudder
Rig
Rig typebermuda sloop
Mast length26.50 m (87 ft)
Sails
Generaltwo semi-battened mainsail skins, one headsail skin
Mainsail area145 m2 (1,560 sq ft)
Jib/genoa area90 m2 (970 sq ft)
Spinnaker areaN/A

The rule

Following the 2017 America's Cup, winners Royal New Zealand Yacht Squadron accepted a notice of challenge from Circolo della Vela Sicilia stipulating a monohull would be used in 2021. Conceptual graphics of a monohull with soft sails and topside canting hydrofoils were released on 21 November 2017, and the first draft of the class rule was published by the defender and the challenger of record on 29 March 2018.[3] The return to monohulls with soft sails after three America's Cups on multihulls with wingsails is reminiscent of earlier America's Cup classes and seaworthy traditions, but the rule included hydrofoils to attract high performance crews and large TV audiences.[4]

Under the protocol, each competing club could build two yachts, but two-boat testing was excluded except during the PRADA Christmas Cup on 17–20 December 2020, and for the defenders during the PRADA Cup 15 January – 22 February 2021. To reduce design and testing costs of the class unique class features, the rule specified foil controlling systems all manufactured by defender team and foil arms all manufactured by the Challenger of Record's builder Persico Marine.

List of AC75 yachts
SyndicateNameShipyardLaunchedCompetitive historyCurrentNotes
New Zealand Emirates Team New ZealandTe AiheETNZ6 September 2019Trial boat (never raced)sold to Ailinghi for AC37[5]
United States American MagicDefiantAmerican Magic14 September 2019Trial boat (never raced)unknown[6]
Italy Luna Rossa Prada PirelliLuna RossaPersico Marine2 October 2019Trial boat (never raced)[7]
United Kingdom INEOS Team UKBritanniaCarrington Boats4 October 2019Trial boat (never raced)[8]
United States American MagicPatriotAmerican Magic16 October 2020Raced in the 2021 Prada Cupcurrent training boat for AC37[9][10]
United Kingdom INEOS Team UKBritanniaCarrington Boats17 October 2020Raced in the 2021 Prada Cup[11]
Italy Luna Rossa Prada PirelliLuna RossaPersico Marine20 October 2020Winner of the 2021 Prada Cup
Lost the 2021 America's Cup to Emirates Team New Zealand (7-3)		[12]
New Zealand Emirates Team New ZealandTe RehutaiETNZ18 November 2020Winner of the 2021 America's Cup[13]

The visible differences between designs have been commented by most of the yachtbuilding community and the specialized press as each of the boats were launched.[14]

Speeds

Potential speed of 50 kn (93 km/h; 58 mph) was claimed based on computer simulations.[15]

Notable high speeds actually recorded in racing were:

  • 49.1 kn (90.9 km/h; 56.5 mph) by Te Rehutai (in 15 and 19 kn (28 and 35 km/h; 17 and 22 mph)) on 17 December 2020.[16]
  • 50.25 kn (93.06 km/h; 57.83 mph) by Britannia during day 4 of the Prada Cup 23 January 2021.
  • 53.31 kn (98.73 km/h; 61.35 mph) by Patriot (American Magic) during day 1 of the Prada Cup Semifinals (in breeze gusting up to 22 kn (41 km/h; 25 mph)) on 29 January 2021.[17]

Controversy

Following the release of the canting hydrofoil design in 2017, Brazilian shipwright Manoel Chaves contacted ETNZ to inform them that he held a patent[18] for the proposed design.[19] Team New Zealand apparently ignored correspondence from Chaves' patent attorneys for over two years before simply dismissing the allegations.[20] ETNZ defended themselves with the statement "every good idea has 1000 fathers".[21]

See also

References
  1. "The Sails of the America's Cup". Sailing World.
  2. Hillary Noble (5 April 2018), America's Cup designer spotlight, North Sails
  3. AC75 class rule version 1.1, americascup.com, 29 June 2018
  4. Bernie Wilson (21 November 2017), Team New Zealand unveils radical foiling monohull, Associated Press
  5. Team New Zealand launch their first AC75
  6. A first flight and a name
  7. 'Luna Rossa', the new flying monohull
  8. Ineos Team UK name their first AC75 'Britannia'
  9. Patriot christened and launched
  10. Chase boats alongside also providing flotation, by tying themselves up to attachment points on Patriot.
  11. INEOS TEAM UK christen 'Britannia'
  12. Luna Rossa launches its second AC75
  13. Emirates Team New Zealand launch Te Rehutai
  14. Matthew Sheahan (23 October 2020), Challenger Revelations, planetsail.org
  15. "American Magic shines as racing begins". Scuttlebutt Sailing News. 17 December 2020. Archived from the original on 15 January 2020. Retrieved 27 December 2020.
  16. "How fast can Team New Zealand's AC75 go? Grant Dalton explains the new boat's design". TVNZ. 5 September 2019. Archived from the original on 27 December 2020. Retrieved 3 November 2020.
  17. "Prada Cup Semi-Final Day 1". America′s Cup. 29 January 2021. Archived from the original on 29 January 2021. Retrieved 29 January 2021.
  18. NZ 740860
  19. Todd Niall (27 October 2020), Brazilian designer claims patent for AC75 canting foils, Stuff Ltd
  20. Scuttlebutt (27 October 2020), America's Cup: Patent problem with AC75
  21. NZ Herald, America's Cup 2021: Team New Zealand refute claims they copied leading designer in construction of AC75's hydrofoils
This article is issued from Wikipedia. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.