It was a welcome sight to see Sir Ben Ainslie leading from the front today out in a very placid and peaceful, if somewhat chilly Palma, Mallorca and bringing to this America’s Cup cycle a new acronym that is straight out of Formula 1 (we presume). In interview, Ainslie repeatedly referred to the ‘HMI’ – the Human Machine Interface – that crossover point where technology must relent to the human touch and vice versa.

It’s a catchy one that more than adequately sums up the technology being deployed in this Mercedes AMG-F1 Applied Science set-up that is rooted in data gathering and logical, positive steps being taken forward. Little matter that INEOS Britannia are the last team to set a sail in this current winter testing schedule, the team looked more than relaxed out on the crystal-clear waters today and the human interface, to adapt the phrase, between Giles Scott, Leigh MacMillan, Luke Parkinson and Ben himself looked like a team on top of their game.

The effective outlawing of the INEOS Britannia proposed ‘towing mast’ by the Rules Committee in decision to Rule Enquiry #25 that is available to view on the AC Official Noticeboard, is undoubtedly a data gathering set-back for the team and the Mercedes engineers back in Brackley, Northamptonshire but Ainslie was circumspect about the impact saying: “The only thing that’s really impacted is that with a towing mast you can get data with just one foil in the water…but we would rather have a proper mast than a towing mast when it comes to sailing.”

And that sailing day is looking set for next week now and after a long weekend back in the shed, it’s clear that the shore team have been hard at work fitting out the boat for sailing. A new mainsheet track, new jib traveller track, hydraulic rams and the return of the slender wind wand were all spied by the on-water recon team (see notes below).

In terms of the tow testing today, it was a long five and a half hour session with the boat docking out at 11am and going through a series of runs, tilts at low speed and time spent by crewmembers out addressing the foils with tape, with Ainslie commenting: “We were working through a range of different speeds and actually probably the most interesting stuff was when we were close to stalling the foil at around the 15 knot range…but we’re trying lots of different speeds, lots of different setups as you can imagine to get the data for the designers,” before adding a very interesting addendum: “but also from an ‘HMI’ perspective how Mercedes onboard the yacht were able to control the boat through different speeds.”

The link up to the Mercedes technicians both in Palma and back in the UK is very much the secret sauce of this British challenger and one that the team are deeply invested in at all levels. It’s a fascinating ‘project’ to watch unfold and with the sailing team looking very comfortable together - and note the power unit were hitting the Wattbikes aggressively today for a sweaty session back at base - the sailing days can’t come quick enough.

On-Water Recon Notes by Justin Chisholm:

What could be the final day of tow testing for the British team ahead of their first attempt at sailing their LEQ12 T6 turned out to be a five-hour session conducted in near millpond conditions on Palma Bay. The boat rolled out on time at 0830 and by 0850 was in the air on its way to being splashed at 0853. As is now the usual run of things batteries were craned aboard the two chase boats and two smaller battery packs were carried in bags aboard T6.

Immediately evident as new additions on the boat were:

• a curved mainsheet traveller track at the back of the aft deck

• a flat jib traveller track at the aft edge of the foredeck including a large enclosure we presume to be a jib car system

• two one metre lateral hydraulic rams either side behind mast track in line with the mast step ball

• The wind wand on the bowsprit stub seen on previous towing outings was back.

Unlike previous towing sessions which had taken place in the western side of Palma Bay close to Magaluf, today the action was in the eastern and central part of the Bay with runs taking place mainly between Palma Cathedral and Arenal. As many as 10 foiling runs were made in close to flat calm conditions.

On the first two runs the tow boat seemed to be struggling for power and the tow was switched to the larger more powerful chase boat. The team made several fast runs – when speeds were in the 20 - 30 knot range – as well as many other runs where the speeds were much lower – in the range 12 - 16 knots.

It was noticeable that the boat was consistently towed offset to the chase boat.

There was a 45 - 60-minute break in activity around 12.30 when the surface of both foil wings were given close attention by a member of the support crew. Evidence of surface patches could be seen after this.

The Recon chase boat covered a total of 44 nautical miles during the day but it should be noted that the AC documentary team were also onboard and so we did not always stay close to the INEOS yacht.

In the interview Ben Ainslie said the goal of the day had been to check the boats systems ahead of potentially sailing next week, to gather performance data, and to work on what he repeatedly called the HMI = Human Machine Interface.

The team has now called a three-day break with no on the water action possible before December 11th 2022.