The America’s Cup is an ornate bottomless, sterling silver ewer crafted in 1848 by Garrard’s of London—who still repair it when needed. It’s an impressive piece of classic craftsmanship, but it is the only thing that hasn’t changed since this nautical battle royale began in 1851. One-hundred, seventy-three years ago, no one imagined yachts racing for the America’s Cup would be flying above the water in barely 6 knots of wind.
This go-around was intense, especially as teams battled tricky conditions off Barcelona. The final nail-biting week came to a close October 20 when Emirates Team New Zealand, under the leadership of skipper Peter Burling and joint helmsman Nathan Outteridge, won the Auld Mug for a third time. They beat the British team, INEOS Britannia, who secured their spot by winning the Louis Vuitton Cup against Luna Rossa Prada Pirelli, earning the right to sail in their first America’s Cup final in 60 years.
Here’s a run-down of why this year’s America’s Cup was special:
THE BOATS
The America’s Cup is 50 percent a test of design and engineering and 50 percent sport. The designers of the various iterations of the AC75 have been increasingly using machine learning to help with CAD (computer-aided design) design—including copious amounts of hydrodynamic and aerodynamic simulations.
They have now removed the backstay and any offwind sails from the design. Like an iceboat, there is so much apparent wind generated by an AC75 at speed, the boats often sail downwind close hauled. To achieve these unprecedented speeds, teams are learning to control the interface between the mast and the sail, and how the sail can help bend or stiffen the mast. The boats’ most striking feature perhaps are the foil cantilever arms that raise and lower hydraulically to offer the center of resistance that keeps the boat upright. Foil wings at the ends of each arm provide the hydrodynamic lift that levitates the hull out of the water. Moveable control surfaces on these foils fine tune the foil’s ability to elevate these goliaths clear of the water surface and give them speeds approaching forty knots.
The new edition AC75 has a total of eight crew— the smaller AC40 trainers only have four (see sidebar). Teams have different crew placement configurations, but essentially, crew is positioned in small foxholes positioned along two “corridors” port and starboard. These corridors are separated by the soft wing-shaped mainsail that creates a longitudinal barrier between the two sides of the hull, which prevents the crew on one side from seeing what happens during maneuvers (or close encounters) on the opposite side. Team INEOS had on each side one helm, two cyclors and one trimmer. Whereas the winning team ETNZ had the trimmer forward, followed by the driver and then the two cyclors. These control positions operate symmetrically from one side to the other and their positions are fixed and synchronous.
The helmsmen each operate a steering wheel dedicated to their side. A small battery-powered hydraulic unit provides the energy to lift the very strong and heavy foil cantilever arm out of the water at the completion of a tack or jibe. From a distance, the competing boats look more or less the same, but on closer look you start to notice small differences. For instance, some position their mast forward of the arms, or engage in different degrees of mast twist.
TESTING
Teams extensively used digital technology to simulate different boat designs and sailing strategies in a virtual environment, allowing faster development and optimization before testing on the water. Each boat is equipped with numerous integrated wireless sensors that collect data on wind speed, boat attitude, foil load and other parameters, which are then analyzed by onboard computers to provide real-time feedback, enabling rapid adjustments.
These carbon flying machines also use the latest in aerospace technology, nano technology, wind tunnel testing and many other advanced simulations, as long as their final design complies with the one-design AC rule.
Cameras are placed all over the race boat to detect thousands of variables, such as wind-load data, and provide real-time information to sailors. In addition, Light Detection and Ranging (LiDAR) technology and bow sensors gauge how the hull is interacting with the water surface, even predicting small changes in sea state. Systems also determine how other teams are doing in the same water and wind conditions.
The advanced simulator game for training the America’s Cup teams have given rise to an e-racing virtual championship this year where eight competitors from seven countries compete in Barcelona for the title and a prize of €50,000. AC Sailing provides a virtual sailing experience based on the AC40 foiling yachts where winners are then invited to race on an actual AC40.
THE SAILS
The mainsail sheeting systems of the AC75 play a critical role in optimizing the boat’s performance, particularly at the high speeds required for foiling. It consists of two layers of sail fabric skins that allow highly precise sail shape control. The twin mainsail set up consists of two layers of sail fabric (skins) running parallel to each other. These skins form an air foil, much like an airplane wing, creating lift as wind flows over them. The interface between the leading edge of the sail and the mast is important. The forward sail skin blends with the after part of the mast, creating a smooth transition from the mast to the sail, ensuring the wind maintains speed and direction, or airflow, across the sail. The twin skin trimming almost looks alive, like a batwing. This is crucial because the crew can adjust the camber (curvature) of the sail to match different wind conditions during the race. In lighter winds, the mainsail can be shaped fuller, providing more lift for better acceleration. In stronger winds, the sail can be flattened to reduce drag, maintain stability, and improve pointing.
The sheet system is designed to handle these dynamic loads by distributing the tension across various points on the sail. Sailors must constantly trim the sheets to manage the loads and ensure the boat stays balanced between sailing and foiling systems, which is critical to maintain stable flight above the water.
The AC75’s rotating mast allows the angle of the mast to be adjusted relative to the wind. This minimizes the airflow disturbance around the leading edge of the sail. The ability to rotate the mast optimizes the aerodynamic transition from mast to mainsail, further reducing drag.
In short, the aerodynamic geometry between the mast and the mainsail in an AC75 is designed to reduce drag, optimize airflow, and maximize the lift generated by the twin-skin mainsail, all the while allowing for real-time adjustments in changing wind conditions.
FOIL DESIGN
The modular foil system on the AC75 is a key innovation in the design of these high-speed lifting monohulls. It allows teams to customize and optimize their boats’ performance depending on the specific conditions they expect to face during a race. In this system, the foils, which lift the boat out of the water to reduce drag and thereby increase speed, are modular, meaning they can be swapped or adjusted depending on the racecourse and weather conditions.
The foil cant system (FCS) is a standardized system provided to all teams, controlling the movement of the foil arms. It allows the foils to be raised or lowered and canted (tilted) to optimize lift and control in various conditions. While the FCS is the same across teams, its use in conjunction with the foil wings is where teams are allowed to innovate.
It consists of two main port and starboard foil arms, and T-shaped foils attached to the ends of these arms. These T-shaped “wings” at the end of each foil arm are the actual lifting surfaces, allowing the boat to rise out of the water to achieve revolutionary speeds.
Teams are constantly optimizing the shape and configuration of their foils to maximize lift and stability, allowing fast turns and greater acceleration in various wind conditions. Team NZ chose smaller wing foils with upturned winglets. Luna Rossa went for a larger surface area with broader tips, and American Magic developed longer, thinner foils. While all foils are made from lightweight, high-strength materials like carbon fiber, the way these materials are layered and constructed can vary, influencing durability, stiffness and overall performance.
THE COMMUNICATION SYSTEM
There is a huge “matrix” of conversations going on via an advanced intercom system for on-board communication on the AC75, which also connects with support boats during training, sea trials and race day. The system is focused on the helmets each sailor is fitted with, which includes sophisticated microphones and earphones that withstand truly extreme marine conditions and noise. It is a complicated system that requires a team of experts to ensure smooth operation. This support team talks to each other during the race through a complex network derived from a mesh of 4G, VHF and Wi-Fi.
RIEDEL Communications GmbH provided the broadband audio system that allowed viewers to hear the action onboard the AC75s and AC40s, along with crew communication, on-shore intercom and digital Tetra radio systems. During the Barcelona event, the goal was to capture and distribute a clear sound, free of any external interference tied to the wind, turning winches, movement of foils, and all the sounds that are heard when flying at maximum speed on a carbon monohull.
During the regattas, it is prohibited to use any kind of external assistance, so intercoms of the support boats were disabled a few minutes before the start until the end of the race, and the team support assumed a “listen-only” mode. All competing boats could only communicate with the race director for information related to the race and with the umpires—the judges who acknowledge protests and assign penalties.
Each team at any one time could have an excess of 50 radios spread across up to five chase boats, shore teams, the design office and the race boat. It’s one big conference call, so communication must be limited and efficient.
THE HUMAN POWER PLANTS
The AC75’s performance is highly dependent on the cyclors who provide the human power that actuates each hydraulic ram and to enable almost continuous sail trim and mast pivot. The energy created by these four cycling stations on the boat pressurize a hydraulic pump, which is then used in all the rams that control everything above deck by the trimmer and below the waterline by the foiler.
The various teams seem to be picking these power sailors from the ranks of Olympic rowing and cycling teams, as they are more physically built for this role. Some teams even figured that cyclors over 90 kilos can produce more power and have sufficient endurance. Barcelona is very hot and the AC75 cockpits are small with limited airflow, so top-of-the-line training, nutrition and recovery strategy for every power sailor is a must.
THE RACE COURSE
The race committee constantly conducts wind sampling since the race area is powered by mother nature. A new Regatta Management System (RMS) has been recently developed, along with a fleet of battery powered, autonomous marks that can reposition themselves in between or during races. The RMS software system also provides tactical information for teams prior to racing, all the tools for the regatta director to set courses and administer races, and all the data and analysis tools for the umpires, including sailing’s equivalent of VAR (video assistant referee). The race committee now operates on shore in a dry office and have forfeited their committee boat.
As published in the protocol, top marks and start mark sensors need to detect more than seven knots to start the race and 21 knots to cancel. As soon as the wind limit is met, the race is live and underway. After the start, if the wind drops, there is a 10-minute leg with one time limit to the windward mark. If this parameter is not achieved, the race is abandoned.
THE UMPIRES
A world-class and highly experienced team of umpires, along with the chief umpire Richard Slater, are no longer on water as their powerboats can’t keep up with the race boats. They use an online tracking system to oversee racing from the safety of an office ashore.
The officials are glued to The Umpire Tool (TUT), which uses GPS trackers to pinpoint the position of the boats on a screen within two centimetres and their direction to within a thousandth of a degree, working at only a third of a second behind real time.
The software shows real time positions of the boats superimposed on the race area with real-time data of boat course, speed, apparent wind angle and wind speed, along with a huge variety of camera angles and digital overlays. For example, if a boat steps outside of the race boundary, only the umpires know as they have the telemetry and digital assets to assess and penalize.
PROTESTS
If a skipper thinks another boat has violated a rule, they press the “protest button” to raise the issue. Umpires review the situation, and if they determine a rule was broken, the offending boat receives a penalty. One typical penalty requires a competitor to decelerate and fall back until it is 50 meters behind a rival. After reaching this position, the boat must wait for a signal from the umpires before resuming full speed.
BROADCASTING
The AC team has thought about everything and involved the best of resources to produce a gala spectacle pulsating with cutting-edge design and technology. WindSight IQ built by Capgemini feeds the America’s Cup Media broadcast systems with real-time wind field visuals and AR/VR designs. WindSight IQ uses LiDAR sensors to measure the wind in real-time and fuses multiple sensor streams using innovative algorithms to enable a wind field to be created over the entire racecourse. The wind field data is then used in the yacht simulator (Ghost Boat) to provide predictions for expert insight and analysis.
Almost 12 cameras per yacht, plus helicopters and chase boats, capture the sailing action in UHD HDR HLG 2020 and surround-sound audio. A key broadcast innovation was the combination of aerial shots with real-time visualization, such as boat tracks, course boundaries and markers, thanks to helicopter cameras equipped with GPS. Additionally, the Bolt6 optical tracking is a new system that calculates the position of race yachts and other assets to millimeter accuracy using only the TV video feeds, powering the precise alignment of video and AR graphics, providing viewers with live insights into racing.
CHASE BOATS
The armada of vessels cramming the port during the America’s Cup in Barcelona included the 13 m Hydrogen Chase Zero Boat designed by Team New Zealand in partnership with McConaghy Boats. These foiling chase boats run on hydrogen fuel cells and have zero emissions, other than water vapor. They have been styled for VIPs of the AC37, with a luxurious interior cabin for high-speed transfers, race spectating and race support.
The 2024 Puig Women’s America’s Cup brought exceptional talent to Barcelona with a new generation of elite female sailors, making this regatta sailed in smaller AC40s an exciting stand-alone competition. Historical footnote: The first woman to sail in the America’s Cup was Susan Henn, who sailed aboard the Irish challenger Galatea in 1886 alongside her husband, Lieutenant William Henn. In more recent times, Dawn Riley became a notable figure as the first woman to have an active racing role aboard an America’s Cup contender. She participated in the 1992 America’s Cup with Bill Koch’s America 3 team. The Luna Rossa Prada Pirelli women’s team—led by skipper Giulia Conti and co-helm Margherita Porro—were pretty unbeatable from the start of the six-leg match race series. The last race was won barely eight seconds ahead of the British boat, Athena Pathway. The UniCredit Youth America’s Cup mixed gender teams feature sailors from 12 countries who are between 18 and 25 years old. After a fierce Fleet Race battle between Italy’s Marco Gradoni and America’s Harry Melges IV of NYYC American Magic, the Italian Luna Rossa Prada Pirelli won. The Women’s cup and the Youth cup were raced in the AC40s.
WHAT’S NEXT
In this playground of hyper-fast water vehicles, some critics do feel that sailing should return to a more simple form—though we are entering the age where the boats could almost sail themselves. The AC75s are almost completely control panel operated, blurring the line of virtual reality, racing, sailing and flying. The lessons from the AC is to directly look at how we can create better public transport with less waste, and less impact on ecology, using wind power. More countries need to open waterways to cleaner transportation in the public water space.
The America’s Cup is the ultimate team sport and it takes time to develop a winning team combining athleticism, technology and safety. The defenders of the cup have already accepted the challenge from Team INEOS for the 38th America’s Cup (AC38), and in time they will get together to set the protocol that governs the next radical design challenge.
It’s fascinating to see how the world’s oldest sports trophy harmonizes tradition with cutting-edge technology and sustainable practices, like a perfect yin-yang balance.
All this technology and it’s as exciting as watching someone else play a video game.