Cup Spy May 13: Light winds turn up an interesting development

by Richard Gladwell/Sail-World NZ 14 May 04:42 PDT 14 May 2024

Three teams "sailed" on Monday.

Coincidentally the wind was largely a 'no-show' in Barcelona and Auckland. American Magic and Alinghi Red Bull Racing made the best they could of the breeze available in Barcelona, but it was not sufficient for serious testing.

In a new feature of Cup Spy, we are downloading the "Photos of Interest" from the AC37 Joint Recon Team reports, identifying any new features they spot on the AC75s sailing from Barcelona. From now through until the Cup itself expect to see new add-ons to the AC75s as the design and development process continues.

What happened in the Cup - May 13, 2024:

• Alinghi Red Bull Racing sailed today out of Barcelona. However light and fickle winds required the AC75 to be tow-started to get foiling. But was unable to stay foiling for a sustained period, and called an end to the session at 1545hrs.
• American Magic was similarly affected by a lack of breeze, However the US team did change down to the J1 jib (their largest) and managed to self start in a breeze estimated by the AC37 Joint Recon Team at 6kts - which is below the minimum required for racing to start of 6.5kts.
• Emirates Team New Zealand were also affected by light winds and cold conditions in Auckland. The intention was to run two AC40s in contested racing practice, however with there being insufficient wind for a productive racing session, the decision was taken to keep the AC75 race team ashore and practice with the Youth and Womens crews sailing alone. On Tuesday May 14, the wind arrived at around 8-10kts, with flat water and both crews went through a combination of race and speed training drills.
• Luna Rossa Prada Pirelli have decommissioned their AC75 in preparation for relocation to the team's America's Cup base in Barcelona.
• INEOS Britannia did not sail today.
• Orient Express Racing Team: No AC37 Recon Team report. However they were sailing their A40 in One Design mode and getting a look at the other teams. A launch date has yet to be publicly advised for their AC75 raceboat.

Commentary: USA makes its mark

The good news from the day was that American Magic was able to self-start in winds of just 6kts. The minimum for starting racing is 6.5kt, and being able to beat this benchmark is significant for the New York Yacht Club team. From the Photos of Interest below, it would seem that the US team may have different wing foils on the port and starboard foil arms. (Foil Declarations yet to be checked)

The fact that the self-start in these conditions was achieved on just their fourth day of sailing is even more creditable.

As mentioned in the last Cup Spy these take-off speeds and apparent wind angles take on a particular interest now that several teams are sailing with wing foils to Version 2 of the AC75 class rule. We have started incorporating these estimates as reported by the AC37 Joint Recon Teams. Over the next few days we may be able to tell if in fact there has been a reduction in minimum takeoff speed, which - along with an 800kg weight reduction - was the objective of new rule. From the information we have seen to date there still seems to be a significant variation between the teams.

It would seem that on the basis of today's observations by the AC37 Joint Recon team, that the stickiness of the AC75s which was a feature of the 2021 America's Cup may be just a memory for some, in the 2024 event. Any team that cannot make this mark will have a serious weak-spot come the start of racing in the Louis Vuitton Cup.

AC37 Joint Recon Team Reports:

Alinghi Red Bull Racing - AC75 - Day 15 - May 13, 2024 - Barcelona

ARBR rolled out their AC75 at 10:30 after a thirty-minute delay.

New versions “E” of both foil wings were declared over the weekend, plus an only new version “B” of one of the foil flaps. In relation to this, new wing tips on the inner sides of the port and starboard side wings were identified, which seem to be symmetric to those on the outer sides. [See new feature "Photos of Interest" below.]

On the other hand, the white hardware equipment positioned on the aft part of the deck which was described the past week, seems to probably be part of a Starlink hardware kit aimed to improve connectivity.

The boat was craned to the water at 10:55hrs and finally docked out at 13:00hrs after an extra one-hour delay, probably due to lack of wind.

The M1-1 was selected for the session, combined with the J2-1. Both sails were hoisted just before heading out of the port at 13:25hrs. [M1-1 version "B" skins declared on 09/05]

Very weak easterly winds dominated the day, staying under five knots of intensity all the time.

Most of the day was spent trying to take-off on both tacks in non-racing conditions. However, it was not possible. During the closest moments to take-off, we recorded 16.0 knots of speed over ground, sailing with a true wind angle of 100° approximately.

Four towing take-offs occurred during the day, being able to stay flying for over a minute after two of them, maintaining a constant speed of 20 knots of speed over ground.

The jib-sheet position on the clew was adjusted and modified in various opportunities and minor works on the jib track were identified.

After towing around looking for wind, ARBR decided to head back to the base at 15:45hrs. Once inside the harbor, sails got lowered, and the team docked at 16:05hrs.

A good show of perseverance from the team trying to test performance in bottom-end wind conditions.

[Sebastian Peri Brusa - Recon on ARBR]

Crew:Sailing: Arnaud Psarofaghis, Maxime Bachelin, Nicolas Charbonnier, Bryan Mettraux. Power: Rolaz, Stahlberg, Maillefer, Schir

Session Statistics: Alinghi Red Bull Racing - AC75 - Day 15 - May 13, 2024 - Barcelona

• Weather: 22°. Sunny
• Wind Strength 3.8-5kts
• Wind Direction: 90° - 105°
• Sea State: 0.25mtrs swell. Flat sea
• Crane In: 1055hrs Dock Out: 1300hrs
• Dock In: 1610hrs Crane out: 1635hrs
• Takeoff Angle TWA: degrees Speed: NA. Not enough wind for sailing/racing during the entire session
• Total Tacks: 4 - Fully foiling: 0; Touch & Go: 0; Touch Down: 4
• Total Gybes: 1 - Fully foiling: 0; Touch & Go: 0; Touch Down: 1

American Magic - AC75 - Day 4 - May 13, 2024 - Barcelona

American Magic rolled out Patriot at 09:50hrs ahead a day committed to light wind take-offs. Small changes to both foils were noted, with four spray rails of different lengths along the port foil arm stock starting from the leading edge, and one spray rail on the starboard foil arm stock below the skeg from the leading edge to trailing edge.

Following a 10:15hrs crane in, hydraulics tests were underway, with mast rotation and FCS testing observed. It looked like foil lifting was being synchronised with something below the foredeck, perhaps jib system, highlighted by (inaudible) communication between helmsman and techs in the foredeck, with two additional tech crew at the mast base. Further work was carried out inside the jib track.

The team docked out at 12:30hrs and hoisted the MN2-1 mainsail and J2-1 jib at the port entrance, with less than 5kts measured on the anemometer at the harbour entrance. Patriot was sailed on a reach in attempt to take-off but to no avail, prompting the team to exchange the J2 for the J1-1 jib. This marks the first time this J1 was hoisted. After some time, the yacht managed to take-off at 90° TWA (True Wind Angle), at approximately 18kts boat speed under 6kts of wind. A foiling tack was attempted but the yacht touched down mid manoeuvre, as the tech crew jumped on board to focus on the jib system.

After an hour and a half of sailing in displacement, AM found some breeze and were able to sail an upwind/downwind, completing four tacks upwind and three gybes downwind, of which just one tack was a touch down. Minimal traveller movement was noted while sailing. During this stint, the team focused on the port foil, with a drone observed flying directly above, before taking a short break.

The team set off on another lap, with as much as 9kts TWS (True Wind Speed) measured at the beginning of the stint, dropping back to six knots half an hour later. Another upwind/downwind lap was attempted, with only one touch and go tack observed and four touch down manoeuvres. At this point the team called it a day and towed the yacht back to port to drop sails at 17:40hrs.

The team docked in at 17:55hrs after just over five hours on the water, of which 153mins (about 50% of the session time) were spent sailing, divided into six stints.

Patriot performed 22 manoeuvres with a 32% fully foiling success rate. Light rust stains were noted on the foil arm hips, just below the skegs, though less significant than previous days.

Crew: Co-Helms: Tom Slingsby, Paul Goodison. Trimmers/Flight Control: Riley Gibbs, Andrew Campbell. Power: Ethan Seder, Cooper Dressler, Colton Hall, John Croom

Session Statistics: American Magic - AC75 - Day 4 - May 13, 2024 - Barcelona

• Weather: 22 °C - Part cloudy
• Wind Strength: 3kts-10kts
• Wind Direction: 100°-120°
• Sea State: 0.2 - 0.4mtrs SE
• Dock Out: 1230hrs
• Dock In: 1755hrs
• Takeoff Angle 80°-90° Unable to takeoff with J2, changed to J1 and took off in 6kts
• Total Tacks:11 Fully Foiling: 2; Touch and Go: 4; Touch Down: 5
• Total Gybes: 11 Fully Foiling: 5; Touch and Go: 4; Touch Down: 2

Emirates Team New Zealand - AC40 OD - Day 6 - May 13, 2024 - Auckland

Back for week two of the latest block with ETNZ and we joined a selection of the youth and women's team docking out at midday, heading down the harbour into a light westerly.

The Team was sailing the AC40 OD boat however using LEQ12 Sails. They hoisted M2 and J1 and set off sailing downwind towards Motuihe Island and then completed some short laps to the west of the island. With a few fresh crew members onboard they focused on working through manoeuvres and showed some quick progression over the first sailing block.

After sailing for roughly an hour the wind had now dropped well below the bottom end of sailing conditions and word was received that the LEQ 12 would not be joining the session which was the originally plan of the day.

After some time waiting for the wind to build again the team towed back up towards the harbour and managed to find a light local SW breeze in Mechanics Bay. Making the most of the breeze and dying light they spent as long as they could sailing laps within the inner harbour cycling through crew during this time.

Heading into the dock just as the light was fading for the evening and stopping the session.

[AC37 Joint Recon Team - Sam Thom and Connor Mashlan]

Emirates Team New Zealand - AC40 OD - Day 6 - May 13, 2024 - Auckland

• Weather: 12-17° Partly cloudy
• Wind Strength: 5-12kts
• Wind Direction: 180°-235°
• Sea State: 0.05
• Crane In: 1100hrs Dock Out: 1200hrs
• Dock In: 1730hrs Crane out: 1800hrs
• Takeoff Angle TWA: NA - AC40OD
• Total Tacks: 25 Fully Foiling: 18 Touch & Go: 5 Touch Down: 2
• Total Gybes: 23 Fully Foiling: 20 Touch & Go: 3 Touch Down: 0

Photos of Interest:

These images were mentioned specifically by the AC37 Joint Recon Teams in their reports, sent to all teams. These draw the teams' attention to new aspects or features of the AC75s which have not been seen previously, or are requested specifically by the teams as part of the Recon process.

Alinghi Red Bull Racing:

American Magic:

Additional Images:

This commentary was written and compiled from video, still images and statistical content extracted from the AC37 Joint Recon program and other material available to Sail-World NZ, including photo files and other on the water coverage from the 2010, 2013, and 2017 and 2021 America's Cups. Its format is intended to give Sail-World readers a snapshot of all teams' progress on a given day or period.