Alinghi Red Bull Racing took advantage of near-perfect conditions out in Barcelona with the thermal ‘Garbi’ breeze delivering 12-16 knots and flat water – ideal for the Swiss to hone technique onboard their AC75 ‘BoatZero’ and try to find the perfect flight to keep the bow clear whilst keeping the power on through manoeuvres.

It was fine margins on the flight control all afternoon and although the beginning of the session saw some dramatic, spray-inducing bow digs post manoeuvre and at round-up, as the session went on, the young Swiss team found a very happy medium with lower flight all round. Gybing still remains an issue and two stops for helmet changes perhaps offered a clue that the devil is in the communications detail with the transition from side to side noticeably improving. Lower flight through the gybes with both boards down appears to be key with BoatZero in its current set-up sporting very different foils from port to starboard. Less of an issue are the tacks and again at lower flight, the Swiss were nailing these foil-to-foil all afternoon with an 86% success rate.

Sail trim was all about power generation in the mainsail, and it was noticeable how little the Alinghi Red Bull Racing flight controllers trimmed the traveller whilst flying the J3 or J4 headsails. When they do, it’s kept to a minimum – in and out rapidly - whilst huge loads are seen exerted on the cunningham and leech tension through the mainsheet ram, to de-power almost immediately once in flight. Alinghi Red Bull Racing’s sail plan is pretty spectacular, the result of non-stop development and it’s here where they look particularly strong in this America’s Cup cycle.

Ernesto Bertarelli was onboard again today as Arnaud Psarofaghis and Nicolas Charbonnier took the duel helm roles alongside Nicolas Rolaz, Bryan Mettraux and Yves Detrey rotating in the Flight Control positions. Between them they did a very good job in unlocking the sailing conundrum that they faced early in the afternoon with BoatZero’s tendency to dig in the bow and found consistent balance both in flight and through manoeuvres once the Chase Boat had put in some marks for upwind/downwind race practice.

Speaking afterwards, Elliot Pilcher one of the Hydraulics Engineers at Alinghi Red Bull Racing offered an insight into the work going on in the bowels of the boat and summed up the day saying: “It was a good day, it was perfect conditions out there, I think, we had flat water and almost up to 15 knots of breeze, that sort of range, so it was a really ideal sailing day and in the upper range everything gets up to full load pretty easily on these boats.”

Talking specifically about his role in the hydraulics department, Elliot commented: “The boat has different modes for different wind conditions so you can't make things too complicated but every day we try different things, the boat is never the same as the day before, every day we go out there is something new in the logic, in the systems, the electronics, the hardware and the sails, so every day is something new to test and calibrate… It's a high-performance beast that boat (the AC75) so it takes a lot of work on the maintenance. You know that you have to juggle maintenance and development, which is the biggest challenge, putting the time and energy into developing the boat and designing systems, improving systems while at the same time keeping everything in top condition and working perfectly every day the boat docks-out.”

And Elliot continued: “I work very closely with the software department, with the logic department and we then work very closely with the sailors, we form a link between the end user if you like and the boat, the control surfaces, the appendages, the sails, we have to make it work so there's a lot of back and forth, lots of meetings, lots of discussions, lots of ideas, lots of changes.”

With so many variables, the Swiss are doing a remarkable job keeping on top of it all and their performances on the water in the AC75 are improving markedly. More to come this week from the team.