Cup Spy - June 23: Spithill on speed, cavitation and co-helmsmen .. Swiss start speed-testing
by Richard Gladwell Sail-World NZ 24 Jun 2023 06:58 PDT
24 June 2023
Alinghi Red Bull Racing - AC40 - Day 37 - June 23, 2023 - Barcelona © Alex Carabi / America's Cup
Coincidentally, Luna Rossa Prada Pirelli, the Italian America's Cup Challenger, based in Cagliari, Sardinia got similar winds to those which prevailed today in Barcelona.
In the dockside interview after today's sailing session Jimmy Spithill (AUS), a co-helmsman aboard the Luna Rossa test boat (or LEQ12), said he didn't expect to get fresh winds like today (around 20kts) in Barcelona at the time of the America's Cup regattas - which start in mid August 2024.
"We had 20 plus kts of wind, and flat water. I wish we would get this in Barcelona. But I don't think we will!"
Most teams seem to be putting considerable design effort into resolving cavitation issues around the foils - which inhibit high speed and can lead to control problems.
"In that sort of breeze and flat water, you're going to hit that cavitation limit," Spithill said. "We're getting some very high speeds. But we get cavitation in those conditions, for sure."
Like most teams, the 2010 and 2013 America's Cup winner would not disclose their top speed to date, or confirm that the had passed the 55kt mark.
"The beauty of today is when you get those flat conditions, you get some pretty good testing numbers - it's pretty static performance. You can really lock the boat in, and just test the numbers.
"I think that's a good day for us to go back and look at the numbers - but again, I doubt we'll be racing in those sort of conditions."
On another point Spithill said that the team was "always trying to remain open minded [on roles on the boat, and whether the alternate co-helmsman does the jib trimming when they are "off watch"]. "It seems like a pretty good compromise at the moment," he said. "I think it'd be fascinating to see what the other teams do. I think everyone's gonna go for the double helmsman and just lock the sides. But in terms of the roles, whether there'll be jib trim, or potentially on the big boat, you could see the cyclists involved a little bit on some of those functions," he added.
What happened in the Cup - June 23, 2023:
- The breeze in Barcelona for June 23, 2023 built from a near calm in the early morning to an average of 17kts, (gusting 20kts) at noon, before easing to 10kts average mid-afternoon and then built back to 17kts average (gusting 19kts) around 6.00pm The direction stayed constant at around 180° (S) until 6.00pm when it veered SW.
- Luna Rossa sailed from Cagliari, in the fresh breeze of the Maestrale, hitting speeds in the mid-40s
- Emirates Team New Zealand sailed for a shorter than usual session, which was cut short ostensibly due to a rain squall. It would seem that this was their last session in New Zealand before leaving for Barcelona.
- Alinghi Red Bull Racing sailed their LEQ12 and AC40-OD against each other - mostly doing speed testing and getting into the mid-40s - with Marcelino Botin (chief designer in attendance) - report below. This was the first time they could evaluate their tubercle wing foil against another boat.
- From what we have been able to see in the AC37 Joint Recon system, American Magic did not sail their AC40. We understand that AC37 Joint Recon has a policy of not covering teams that are sailing AC40 One Designs alone.
- INEOS Britannia did not sail and is in transition from Mallorca - they are expected to resume sailing on August 1
- No further news from the Orient Express Team (formerly K-Challenge).
Luna Rossa Prada Pirelli - LEQ12 - Day 73 - June 23, 2023 - Cagliari
From the AC37 Joint Recon Team - Michele Melis:
The Italian LRPP team opted for an early roll out of the LEQ12 prototype to catch some Maestrale before it reached unfeasible strength in the afternoon. The mast stepping procedure was precise and well timed by the team which craned in the yacht at 7:30 to run through all routine checks.
Dockout was scheduled for 8:15, the mainsail M2 was locked in the mast fitting. Four crew boarded the prototype and the Italian LEQ12 was towed offshore of Sant'Elia to hoist the M2 main with the J4 jib. The seastate was flat and the shifty offshore NW-NNW breeze reached upper range with up to 17kn gusts being displayed by the Recon Unit anemometer.
Once all set, the LEQ12 took off on port tack, before tacking immediately and bore away quickly leaving behind all chase boats for a long and fast downwind run - occasionally gybing and trimming back towards Cagliari for some tacks. This course path was replicated several times while some modes testing was observed. Downwind boat speeds on broad reach seemed to be within 42-44kts while upwind within 35-37kts close reach according to onboard GPS. Certainly the flat seastate was optimal for some cross checks with numerical predicted performance on straight line.
Once this phase was completed, Chase-2 dropped four marks for the usual race course. After sailing mostly straight-line for approximately 45 minutes, the following 15 minutes were spent on the race course before coming to the first break of the day on the top mark. A first time-on-distance for the day was observed and, after nailing the start by the second, the LEQ12 completed six more laps until stopping in the middle of the course.
Shore crews have been observed entering a hatch on the bow for some checks below deck while sailors seemed to focus on debriefing with some adjustments on the jib clew. Two more starts with time on distance were followed by some additional laps, before Chase 2 recovered the marks and the LEQ12 executed a series of quick tacks, bear aways before heading towards the harbour, dropping the windward board and calling it a day.
A foiling time of 118 minutes out of 190 in total, with 31 tacks, and 25 gybes were counted [Michele Melis AC Recon].
Session Statistics: Luna Rossa Prada Pirelli - LEQ12 - Day 73 - June 23, 2023 - Cagliari
- Weather: Sunny 29°C
- Wind Strength 15-18kts
- Wind Direction: NW
- Sea State: Flat
- Roll out: 0730hrs Dock Out: 0815hrs
- Dock In: 1140hrs Crane out: 1300hrs
- Total Tacks: 31 - Fully foiling: 29; Touch & Go: 4; Touch Down: 0
- Total Gybes: 29 - Fully foiling: 22; Touch & Go: 3; Touch Down: 0
Crew: Marco Gradoni, Jimmy Spithill, Andrea Tesei Umberto Molineris
Alinghi Red Bull Racing - LEQ12 - Day 37 - June 23, 2023 - Barcelona
From the AC37 Joint Recon team:
Alinghi Red Bull Racing rolled out their AC40-7 (Red bowsprit) and AC40-4 (Yellow bowsprit) at 09:00 and 09:35 respectively, stepping the rigs and craning in the yachts separately on the forecourt.
Again the ‘Garbi’ wind came through at midday, fluctuating between 10-15 through the day. Both boats started with J3 OD jibs, though the Yellow boat sailed with their M1-1 LE mainsail, while the Red boat with the M1-1 OD. All sailors remained in the same positions as the previous day, except for Pietro Sibello who was on the port helm of the Red boat, for his first sail on the AC40. [SW: He replaced Phil Robertson for today's sail.]
Alinghi Red Bull Racing's chief designer, Marcelino Botin was out on Chase Charlie. [SW: Indicating this was a day for two-boat speed testing, with AC-40 Yellow set up as the LEQ12, or test boat and wearing the tubercle (Delta) wing foil.]
The team started the day with two boat testing side by side, sailing long stretches as well as tacking and gybing duels, gathering further data on their Delta Foil, as well as comparing the two mainsails.
The remainder of the day was spent working on pre-starts and sailing around the 1NM windward leeward course. At 16:00 the windward mark was at a heading of 180, while the wind direction was at 195°.
Only one race was held, with the Yellow [LEQ12] boat taking the win after covering all the way upwind, securing the lead by 200m at the first mark.
After the first race, it appeared that the Yellow [LEQ12] boat was having problems, though it was not clear what exactly. Sails were dropped and the yacht was towed back to base at 16:20.
The Red boat [AC40 One design mode] stayed out for another 30 minutes.
Damage to the ‘Delta Foil’ after sailing was apparent again, specifically about the foil flap centre. The team spent five hours on the water. The recon unit covered 60NM, of the 38 maneuvers performed, 95% were fully foiling.
A strong session to end the week.
Session Statistics: Alinghi Red Bull Racing - LEQ12 - Day 37 - June 23, 2023 - Barcelona
- Wind Strength: 11-13kts
- Wind Direction: SSW
- Weather: Sunny 27°C
- Sea State: Beaufort 2-3
- AC40-4 Crane In: 1000hrs Dock Out: 1200hrs
- AC40-7 Crane In: 0925hrs Dock Out: 1200hrs
- AC40-4 Dock In: 1635hrs Crane Out: 1650hrs
- AC40-7 Dock In: 1700hrs Dock Out: 1725hrs
- Total Tacks: 16; Fully foiling: 14; Touch & Go: 1; Touch Down: 1
- Total Gybes: 16; Fully foiling: 15; Touch & Go: 1; Touch Down: 0
- AC40-4 - Yellow bowsprit; AC40-7 - Red bowsprit;
- The AC40-OD used One Design Wing Foils, Foil Arms, Rudders and Rudder Elevators. The LEQ12 used test Foil Arm, Wing Foil, One Design Rudder Elevator
Crew: Arnaud Psarofaghis, Maxime Bachelin, Nicolas Charbonnier, Pietro Sibello, Bryan Mettraux, Yves Detrey, Lucien Cujean, Jason Waterhouse
Emirates Team NZ - LEQ12 - Day 37 - June 23, 2023 - Auckland
From the AC37 Joint Recon Team [Alastair Moore AC-Recon]:
Under grey damp skies the LEQ12 was rolled out of the shed and was on the docks edge at 10.02.
The development foil was on the starboard arm, which had new fences between the foil and the tapered junction.
The rig was stepped by 10.11 and she was floating in the pen at 10.21.
With the one design mainsail plugged in she was towed from her berth and had the main on the lock at 11.10 followed by the #3 development jib at 11.12.
She was up and sailing at 11.16 beating out of the harbour in a light 6-7 knot ENE breeze right on high tide. The yacht made its way out to the Motukorea channel where she did two windward leeward laps, sometimes needing a tow up when the breeze faded below 7 knots.
After this she reached out the Rangitoto channel and down the East Coast Bays doing three sets of two full circles before turning and reaching south. She came to a stop off Rough Rock (near North Head) at 12.30 and dropped sails.
The session was short and I feel the answer they gave as a squall was forecast to come through was covering up for some defect.
The yacht was back at base by 12.54.
Session Statistics - Emirates Team NZ - LEQ12 - Day 37 - June 23, 2023 - Auckland
- Weather: 15°C Sunny, overcast, rain
- Wind Strength: 10-12kts gusting 20kts
- Wind Direction: ENE
- Sea State: Flat
- Roll out: 1021hrs Dock Out: 1103hrs
- Dock In: 1254hrs Crane out: 1313hrs
- Total Tacks: 25 - Fully foiling: 22; Touch & Go: 2; Touch Down: 1
- Total Gybes: 16 - Fully foiling: 15; Touch & Go: 1; Touch Down: 0
Crew: (LEQ12) Nathan Outteridge, Peter Burling, Andy Maloney, Blair Tuke
Wind readings and direction in Barcelona - June 23, 2023
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, 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.