AC72

  (Redirected from AC72 class)

The AC72 (America's Cup 72 class) is a class of wingsail catamarans built to a box rule, which governs the construction and operation of yachts competing in the 2013 Louis Vuitton and the America's Cup races. The class was subsequently replaced by the smaller AC50 class.

AC72 New Zealand Aotearoa San Francisco 01.jpg
Team New Zealand AC72, San Francisco Bay +
Development
DesignBox rule[1]
Boat
Crew11
Draft4.4 m (14 ft)
Hull
TypeCatamaran
Hull weight5,900 kg (13,000 lb)
LOA26.2 m (86 ft)
LWL22.0 m (72.2 ft)
Beam14.0 m (45.9 ft)
Rig
Mast length40.0 m (131.2 ft)
Sails
Mainsail area260 m2 (2,800 sq ft) (wing estimate)
Upwind sail area580 m2 (6,200 sq ft) (wing and gennaker estimate)

BackgroundEdit

Following the 2010 America's Cup, where the Golden Gate Yacht Club's USA 17 trimaran defeated the catamaran Alinghi 5, it was decided by the winners that the next America's Cup competition would be sailed in catamarans in the hope of making the sport more attractive to television audiences.[2] At the same time a smaller sister class, the AC45, was developed to allow teams to practice and adjust to the new formula as well as create a greater exposure of sailing to the general public with the America's Cup World Series.

SpecificationsEdit

The AC72 has the following maximum specifications:[3]

  • overall length: 26.2 metres (86 ft)
  • waterline length: 22.0 metres (72.2 ft)
  • beam: 14.0 metres (45.9 ft)
  • weight: 5,900 kilograms (13,000 lb)
  • maximum draught: 4.4 metres (14 ft)
  • crew: 11

Maximum Speed

Using foils for the first time in the America's Cup the AC72 was expected to sail faster than the wind: upwind at 1.2 times the speed of the true wind, and downwind at 1.6 times the speed of the true wind.[4][5] But in fact it proved faster, averaging about 1.8 times the speed of the wind with peaks slightly over 2.3.[6] A multiple of 2.79 times wind speed was achieved by Emirates Team New Zealand in practice, which sailed at 44.15 knots (81 km/h, 50 mph) in 15.8 knots of wind on July 18, 2013.[7]

Typical racing speeds are over 30 knots (55 km/h, 34 mph) with the boats capable of sailing well over 40 knots (74 km/h, 46 mph) in the right conditions. The fastest race speed recorded was on Emirates Team New Zealand which was 47.57 knots (88 km/h, 55 mph) in 21.8 knots of wind (2.2 times the wind speed) on September 24, 2013.[8]

Features [9]

  • Pedestals
  • Multi speed winches
  • Backstays
  • Crossbeams
  • Wing Pod
  • Digital Performance Indicators
  • Soft Sails
  • Wing-controlled cables
  • 3 separate cockpits
  • Buttons on wheels

In competitionEdit

The boats have been used in the 2013 Louis Vuitton Cup and the 2013 America's Cup. By mid-June 2013, all boats had "lined up" and conducted trials against each other on the planned race track in San Francisco Bay, notably Oracle Team USA vs. Artemis Racing and Emirates Team New Zealand vs. Luna Rossa Challenge. [10][11]

List of AC72 catamaransEdit

AC72 catamarans
Syndicate Name Shipyard Launched Competitive history Subsequent history
  Emirates Team New Zealand New Zealand Cookson Boats 21 July 2012 Trial boat Decommissioned
  Oracle Team USA 17 Oracle Racing 30 August 2012 Trial boat. Extensively damaged in a 16 October 2012 capsize. Relaunched 4 February 2013.
  Luna Rossa Luna Rossa Persico Marine 26 October 2012 Raced in the 2013 Louis Vuitton Cup On exhibit at the Museo Nazionale Scienza e Tecnologia Leonardo da Vinci
  Artemis Racing Big Red King Marine 3 November 2012 Trial boat Deemed a "complete loss" after capsize on 9 May 2013
  Emirates Team New Zealand New Zealand Aotearoa Cookson Boats 3 February 2013 Winner of the 2013 Louis Vuitton Cup
Lost the 2013 America's Cup to Oracle Team USA (9-8)
  Oracle Team USA Oracle Team USA 17 Oracle Racing 23 April 2013 Winner of the 2013 America's Cup On exhibit at the Mariners' Museum in Virginia.
  Artemis Racing Big Blue King Marine 22 July 2013 Raced in the 2013 Louis Vuitton Cup

IncidentsEdit

On 17 October 2012, Oracle Racing's AC72 pitchpoled (somersaulted) and capsized, causing severe damage to the yacht. The wingsail was completely destroyed while being swept under the Golden Gate Bridge by a strong ebb tide.[12]

On 9 May 2013, Artemis Racing's AC72 pitchpoled and broke apart, resulting in the death of crew member Andrew Simpson.[2]

The other two teams, Luna Rossa Challenge, and Team New Zealand, have both suffered minor setbacks, including hitting seals[13] and damaging their wing sails, resulting in loss of sailing time.[14]

See alsoEdit

ReferencesEdit

  1. ^ "America's Cup 2013 - AC72 Catamaran Class Rule Released" (Press release). Cupinfo. 15 October 2010.
  2. ^ a b Elias, Paul; Wilson, Bernie (9 May 2013). "British sailor dies during America's Cup practice". Associated Press. Archived from the original on 2014-07-04.
  3. ^ "AC72 Class Rule". America's Cup Official Race Notice Board. Archived from the original on 2013-10-01. Retrieved 2013-08-12.
  4. ^ "AC34 Multihull Class Rule Concept Document" (PDF). 34th America's Cup. Retrieved 2010-09-14.
  5. ^ "New high performance yachts for 34th America's Cup" (PDF). 34th America's Cup. 2 July 2010. Retrieved 2010-09-14.
  6. ^ "Emirates Team New Zealand gets leg up on ORACLE TEAM USA". 2012-13 America's Cup Event Authority. 7 September 2013. Archived from the original on 21 September 2013. Retrieved 8 September 2013.
  7. ^ "Kiwis Reach Record Speed in AC 72-Foot Catamaran". NBC. 19 July 2013. Retrieved 2013-09-21.
  8. ^ "Day 14 Racing Blog". America's Cup. 24 September 2013. Archived from the original on 27 September 2013. Retrieved 25 September 2013.
  9. ^ Drummond, Mike. "AC34: The Anatomy of an AC72". Sail Magazine. Retrieved 2021-06-29.
  10. ^ "Line-up spurs Artemis Racing into 'improvements'". America's Cup. 22 February 2013. Archived from the original on 22 May 2013.
  11. ^ "Two up on San Francisco Bay". 13 June 2013. Archived from the original on 28 August 2013.
  12. ^ Johnstone, Duncan (17 October 2012). "Oracle's AC72 catamaran badly damaged". Stuff.co.nz.
  13. ^ Fitzpatrick, Lynn (8 August 2013). "No Excuse for Another America's Cup Death". World Regattas. Archived from the original on 29 September 2013.CS1 maint: bot: original URL status unknown (link)
  14. ^ Johannsen, Dana (20 March 2013). "Team NZ play down setback". The New Zealand Herald.

External linksEdit