Luna Rossa returned to the water with a new rudder design that had both the sailing team and the recon crew watching closely, and by afternoon it had produced a broach dramatic enough to test the blade's limits.
The recon team, tracking the session from the water, described the new blade as having "more blade area at the top extending the leading edge forward, and slightly less area at the bottom of the blade." In length it looked close to the earlier rudder R05, though that will need confirming once measurements are taken from footage shot at crane-out.
Conditions were gentle to begin with. Light morning airs gave the crew a clean introduction to the new foil, and the first session passed with only a small hiccup entering the final tack, where the bow dipped noticeably.
The afternoon told a different story.
After lunch, with the breeze building, the team pushed harder. According to the recon report, "the boat practiced some aggressive one-board bear-aways followed by consecutive gybe series before switching back to bear-aways, now with the windward board half immersed." It was on one of these that things went wrong. The new rudder ventilated and stalled during the bear-away, the boat trimmed bow-up significantly, broached, and crashed hullborne. No major damage occurred, and the crew reacted and kept sailing shortly after.
Vittorio Bissarro, one of the most experienced flight controllers and trimmers in the America's Cup, explained what happened. "Well, it was kind of simple, we lost the rudder, so we didn't have any control of the blade or the yaw of the boat, and that promoted the boat to bear away and pass through the power zone. It was a kind of a dangerous situation."
His instinct in that moment was straightforward. "So yeah, the reaction there was just being sure to put the rudder in the water. So don't care about the bow, the distance of the bow from the water, just keep the elevator in the water because what really can cause damage in that situation is popping the rudder."
The team then repeated rudder loading on a beam reach before switching to pre-start practice closer to shore in 12 knots of sea breeze from 165 degrees.
Dock-out had been scheduled for 11:30, with the legacy mainsail M1-8 paired with the J3-1 for the tow out. Marco Gradoni helmed on port with Gigi Ugolini trimming and Maria Giubilei in the fifth position, while Peter Burling steered on starboard alongside Vittorio Bissaro and an engineer in the sixth spot. Later in the day, Ruggero Tita replaced Gradoni, Molineris replaced Bissaro, and several engineers rotated through the sixth position.
Breeze was light when the towline was slipped at 12:06, just 7 to 9 knots from 190 degrees over a flat sea. Tacks in the first session were clean and dry, with bulb-to-bulb times of 5.5 to 6 seconds, and the gybes that followed were well executed at around 6 seconds. Jib ease on the bear-aways seemed a touch slower than usual, and the last downwind manoeuvres of that stint were slightly more touch-and-go on the exits.
The second stint is where the drama unfolded. The crew first trimmed the boat bow-up with the whole rudder immersed to gather footage of the updated steering system, then pushed into the aggressive manoeuvres that led to the ventilation and stall.
By the third session, starting at 13:59, the sea breeze had swung southeast to 145 degrees at 13 to 14 knots, and the smaller J4-9 jib went up in anticipation of more wind and a building chop. Tacks were sharp early on, though the gybes that followed were scrappier, and downwind stability looked slightly off compared to recent sailing days, possibly a consequence of the new rudder iteration. After several upwind and downwind legs, the boat came off the foils for a battery swap.
The fourth session, from 14:33, brought several minor rudder ventilations and losses during straight-line sailing and manoeuvring, suspected to be voluntary as the team continued testing the new blade. The crew then ran five prestart routines closer to shore, focusing on tight, full-circle execution, before a fifth and final stint saw more prestart practice ahead of the return to the harbour.
The team wrapped up just after 3pm having logged 135 foiling minutes across five separate sailing stints. They plan to be back on the water on Friday 28 August.
