The British America’s Cup team has become the fourth challengers to unveil their new AC75. INEOS Britannia revealed their AC75 in the early hours of morning, as the foiling monohull – which is code-named RB3 – emerged from the INEOS Britannia base in Barcelona in preparation for having the rig stepped in readiness for its first ever sail. 

Team Principal and Skipper of the Challenger of Record,  Sir Ben Ainslie said RB3 would be “on the water very soon”.

COO David Endean confirmed the team will first perform some initial tow testing and systems checks before hoisting sails.

The British America’s Cup team’s AC75, code named RB3, came out of the shed for pre-sail preparation on Saturday 20 April.

The British America’s Cup boat was built by Carrington Boats in Hythe, on the south coast of England, before being transported to Brackley, in Northamptonshire, which is the centre for the Mercedes-AMG PETRONAS F1 Team, where the F1 Team’s Applied Science division partnered with INEOS Britannia for the design and build. On 2 April, RB3 left Turweston for its journey to Spain, arriving at the INEOS Britannia Barcelona base on 6 April, delivered by GAC Pindar.

The build has been a two-and-a-half year project, and the team now has less than four months in order to get to grips with the new sailing yacht ahead of the first Preliminary Regatta races for the AC75s on 22 August.

The INEOS Britannia shore team working on the AC75 race boat ahead of first test sails. Image: 37th America’s Cup recon

Ainslie said: “This is a big day for the team. We have been keeping RB3 under wraps for such a long time that it’s almost surreal to see her out of the shed and in public view here in Barcelona. 

“Thousands of hours of work have gone into this boat and so it’s great to finally reveal her to the world. Things are really stepping up in the campaign now, and we are looking forward to launching RB3 and getting out on the water very soon.”

British AC75 unveiled

Not all of RB3 has been unveiled – the foils appear to have ‘socks’ concealing the lower arms (teams are allowed to conceal their foils until the boats are first launched in water) – and there was no rudder in place. The eye-catching livery also has something of a ‘dazzle ship’ effect in the dark. However, the early shots suggest a flared bow, and a fairly bulbous ‘bustle’ under the hull, with a finer skeg running underneath it, which stops forward of the expected rudder position.

Bow on view of INEOS Britannia’s new AC75 showing the boat’s ‘bustle’

AC75 ‘bustles’ are designed to achieve an end plating effect between the boat and the sea, effectively sealing the boat to the water’s surface for aero and hydrodynamic efficiency – but balanced against additional drag during take-off and touch-downs. Of the four boats so far, RB3 initially looks to be among the most substantial, with Luna Rossa Prada Pirelli’s appearing to be a finer, slimmed down design.

Each of the AC75s unveiled so far has also removed volume aft – in part a response to rule changes which mean that runners are no longer required – with RB3 showing radically sloping topsides from what we assume are the top of the cyclor pods down to the transom, meeting with a very flat under section.

The boat’s unveiling also showed the suspended aerial gantry which the team has built above the deck of RB3, a learning from its partnership with INEOS Mercedes to make key maintenance work more efficient in order to reduce time required in the shed.

INEOS Britannia has built an aerial gantry suspended above the race boat pit lane area, inspired by their partnership with Mercedes-AMG PETRONAS F1 Team, to improve efficiency in repairs and maintenance

We’ll have a fuller analysis of the different AC75s’ hull shapes, and what the teams are aiming to achieve in the challenging waters off Barcelona, coming soon, plus more images of RB3 once the boat has been made public in daylight.