The 100-footers in the Sydney-Hobart Race - A Battle of Giants

Another publication for François Chevalier & Jacques Taglang, translated from French. They write:

Launched three weeks before the 2005 edition of the Sydney to Hobart race, Wild Oats XI proved an immediate success. Since then, she has hoarded silverware to the point of appearing to be invincible (six Sydney-Hobart line honours wins, including two trebles for winning on handicap and setting a new record). Though her appendages had been revised continuously, the yacht was still prone to nose diving when running in a seaway, thus limiting her speed potential. A solution licensed from Dynamic Stability Systems was developed and tested during the 2013 Hamilton Island Race Week: It consists of a lateral retractable horizontal foil, located just below the waterline and alongside the mast.

The thick carbonfiber foil measures 55cm along the chord and extends 275cm outside the hull. It generates vertical lift to the forward part of the yacht, thus providing better planing ability.

sailplan, body plan, sheer plan, half-breadth plan and deck layout of Wild Oats XI in her 2013 configuration, draft courtesy © François Chevalier

The forward centerboard, with a thick profile, was added in 2012 to stabilise the yacht and avoid broaches to windward or to leeward when reaching the crest of waves in downwind sailing. Wild Oats XI's light displacement and her long waterline and bowsprit allow the centre of effort of the sails to shift forward significantly when setting downwind sails; The forward centerboard prevents a lee helm in these conditions.

Other structural changes in 2012 enabled weight savings in the hull, so the keel ballast could be increased. Winglets resembling a shark’s caudal fin were placed on the bulb tail to generate lift from the tip vortex. They also improve lateral resistance somewhat when the keel is canted.

Wild Oats XI's lines were drawn using many photographs and emphasise a slightly rounded bilge, distinctively flaring topsides, a narrow (4.10m) beam at the waterline and a moulded depth forward of the finkeel. When she heels, the waterline extends to the full length of the hull and the wetted surface is reduced, but the flaring topsides do not provide lateral resistance like more recent yachts with chine-bilged hulls (Juan K designed Perpetual Loyal).

sailplan of Wild Oats XI in her 2005, 2007 and 2012 configuration, draft courtesy © François Chevalier

Wild Oats XI was launched in 2005 as a development of the 60ft Wild Oats IX (2002) and the 66ft Wild Oats X (2004), all penned by the same designers, Reichel/Pugh, with a CBTF appendage configuration including a canting keel, an aft rudder and a canard rudder forward of the mast. Between 2007 and 2008, the canard was removed and two lateral daggerboards were fitted before the mast, with a 10° slope, thus correcting the yacht's tendency to sail on her topsides when heeling.

Wild Oats XI
Yacht designers: Reichel/Pugh
Shipyard: McConaghy's (AUS)
Christened: December 2nd, 2005
Length of Hull: 30.48m
Overall Length: 33.83m
Load Waterline Length: 29.70m
Beam: 5.40m
Mast length: 44.10m
Draught: 5.50m
Displacement: 32 metric tonnes
Ballast: 14 metric tonnes
Mainsail area: 382m²
Jib sail area: 228m²
Genoa sail area: 505m²
R1 headsail area: 880m²

sailplan, body plan, sheer plan, half-breadth plan and deck layout of Perpetual Loyal in her 2013 configuration, draft courtesy © François Chevalier

The lines of Perpetual Loyal were developed from the trends in the IMOCA Open 60 and the Volvo Open 70 circuit. Scaled to 100 feet, the lines are so sleek that is difficult to read the shape of the yacht in her aftersections. Because of this, her horizontal sections (which are parallel to the waterline) all stop abruptly at the transom. Half the yacht's weight is located in the canting keel which may be swung to windward under sail. In a breeze, 8 cubic metres of liquid may be pumped to her ballast, allowing for a huge righting moment that her opponents cannot match. Furthermore, Loyal's ability to plane offwind give her exceptional top speed. During the SOLAS Big Boat warmup challenge ahead of the Sydney-Hobart race, she was taken over by Wild Oats XI after her spinnaker blew out, a reminder that victory can only be achieved if nothing fails.

Perpetual Loyal (formerly Rambler 100, Virgin Money, originally Speedboat)
Yacht designer: Juan Kouyoumdjian

Shipyard: Cookson Boats (NZ)
Launched: April 17th, 2008

Length of Hull: 29.99m
Overall Length: 33.59m
Load Waterline Length: 29.99m

Beam: 7.00m

Draught: 5.70m

Air draught: 46.50m

Bowsprit: 3.60m
Displacement: 30.6 metric tonnes

Ballast: 15 metric tonnes

Liquid ballast tanks: 8,000L
Upwind sail area: 630m²
Downwind sail area: 1,340m²

Ordered by Grant Wharington en 2003, Skandia won lines honours in her inaugural Sydney-Hobart race. In the 2004 edition of the race, she retired after losing her keel whilst she was heading the fleet. Her canting keel received several modifications thereafter: Originally 4.80m, her draught increased to 5.20m in 2005, 5.50m in 2006, and finally a staggering 6.80m in 2009, which is a record for an IRC maxi. The hull was also entirely remodelled in the rear third of the yacht's length, achieving sleeker and fuller lines.
Wharington had hoped that the dark livery of his yacht, now called Wild Thing, would have distinguished her from the rest of the fleet, but Perpetual Loyal's new black coat and 7-metre beam could cast a much longer shadow...

Wild Thing (formerly Skandia)
Yacht designer: Don Jones

Shipyard: Hart Marine (AUS)
Launched: October 2003

Length of Hull: 30.00m
Overall Length: 32.90m
Load Waterline Length: 30.00m

Beam: 4.95m

Draught: 6.80m

Air draught: 40.00m

Bowsprit: 2.90m
Displacement: 26 metric tonnes

Liquid ballast tanks: 9,000L
Upwind sail area: 492m²
Downwind sail area: 1,050m²

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