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Speed vs. Control: How to Win the Oldest International Trophy

By: Brayden Yee


Team New Zealand used Peloton-like cyclors to power their hydraulics, which are cited as a key factor to their success (Source: CNN)

Background


The America’s Cup is the oldest contested trophy in international sporting history. Dating back to 1851 and containing 36 editions, the sport of competitive sailing has certainly seen its evolutions, both strategically, and technologically.


The 35th America’s Cup in 2017 specifically showed a massive technological jump, the addition of cyclors to power the hydraulics system. Among the components of the sailing catamarans, one key part is the method to power the hydraulics of the boat. The hydraulics system is responsible for the control of the mainsail, the largest sail on the boat. This includes the direction it is pointing, as well as the amount of tension on the sail itself. It is a key component to winning an America’s Cup race, as it not only helps with the speed of the boat but also the control over the course of the race. While the speed of the boat is important, having control over the boat is especially important due to the many jibes and tacks (turns) that occur throughout the course of a race.


Breakdown of the Crew:

Each team consists of 3 main roles, containing a total of 6 people. The helmsman, also known as the skipper, is the “driver” of the boat. They control the steering of the boat and usually make the calls for when to switch sides along with the tactician. The tactician’s job is to formulate the route to complete the course as quickly as possible. This includes the direction of the sail, and when to turn. Successful races usually hinge on the tactician's ability to navigate the course well. The remaining 4 members are a part of the hydraulics team. They typically have the highest heart rates, and switch sides most often. 


Format of the America’s Cup:

The format of the 35th America’s Cup held in Bermuda consisted of a round-robin system to determine the finalists, and then a set of races between the finalists to determine the winner. As the challenger of the 35th America’s Cup, Emirates Team New Zealand started off with -1 points, to win the America’s Cup, either team would need 7 points, meaning that New Zealand would need to win 8 races, whereas USA would only need to win 7.


The races consisted of 7 legs, each leg being roughly 1-2 nautical miles long. The end of each leg contained a buoy which each boat had to circle around to start the following leg. During each phase of the race, the boats would also need to turn as they approached the boundaries of the racing course, resulting in a loss of speed.


The main difference between Team USA and Team New Zealand was the method used to power the hydraulics system. Team USA opted to use the traditional grinders, which work similarly to a hand-powered coffee grinder in order to generate power. In contrast, Team New Zealand decided to use peloton-like bicycles called cyclors. These cyclors proved to be effective, leading to New Zealand's 7-1 victory and making them the victors of the America’s Cup. Cyclors were subsequently banned for the 2021 America’s Cup, then unbanned for the upcoming 2024 edition.


Many factors contribute to race victories in the America’s Cup. While speed is of course important, being able to stay consistent in speed is also a huge factor. The fastest the boat moves is during “fly time”, which is the time when the hull is not touching the water (the boat is on foils). Being able to consistently stay on foils requires the boat to stay above a certain speed consistently, and failing to have that can result in a loss.


This is an example of a boat during fly time as the 2 long legs of the boat (hull) are not touching the water (Source: Rockwool.com)

Data Analysis


Average Speed Over Ground. The dotted line represents the winner of each race

Speed Over Ground (SOG) is the term used to describe the speed of the boats during the course of a race. In this case, the speed is being measured in nautical miles (knots), which is roughly 6,076 feet. The graph shown above illustrates the average SOG through each of the races. The average speed does fluctuate between each one, but that is to be expected as wind conditions are expected to vary day by day. 


While it can be observed that the team that had the higher average speed throughout the course of the race won 5/9 times, there were 4 (5, 6, 8, 9) races where the slower team on average ended up winning. This can be due to a multitude of factors, such as inefficient routing by the team, or rule violations resulting in distance penalties. However, the most likely culprit of this can be traced to the consistency factor of speed. If the boat fails to remain on foils, there can be a huge time loss due to the increase in drag and resistance of the hull being in the water. Resultantly, the boat moves slower, and more energy has to be used in order to increase the speed of the boat through the hydraulics system.


Each team must make a circle around one of the buoys in order to pass through Gate 2 (Source: American Sailing Association)

During each leg of the race, the catamarans must make a loop around a buoy to start the next leg. This is by far the instance where the boat loses the most amount of speed, due to the boat being in the turning motion for the longest amount of time. Using the minimum speeds in legs 2-6 from races 5, 6, 8, and 9 came up with this data.


The average minimum speed per leg for each team in each race

The four races highlighted above are the ones where the team that had the lower average speed through the course of the race won. Races 5, 8, and 9 were won by New Zealand, while race 6 was won by the United States. Legs 2-6 specifically are used as legs 1 and 7 are structured much differently in comparison since there is no turn that has to be performed at the end. In each of these races, the team that maintained a higher average minimum speed always won. The team with the higher average minimum speed stayed on foils for a greater portion of the race and therefore had longer fly time. This is the result of being able to control the boat through the turns.​ The hydraulics system is an important component of maintaining control. Even though they were slower in the race overall, the control that was able to be maintained by the boat was a contributing factor to the victory in the race.


Full graph with all nine races

When taking into account all 9 races, the pattern continues. The team that maintained the higher minimum speed on average also won the race. 


Overall, the team that spent the most time on foils during the race was the team that won, spending as little time being dead in the water trying to get speed and instead being able to focus on maximizing the efficiency in the route.


Races in red denote the races where the slower team won

The last thing that will be mentioned is the difference in the finishing time between the two teams in each race. The 2 closest races were races 6 and 7, where each team finished roughly 11 seconds apart. These 2 races also happen to be the closest when comparing the average minimum speeds of the two boats. On the other hand, the race with the largest finishing time difference was race 5, where the difference in average minimum speed was the highest by a long shot. While the results can speak for themselves, the magnitude of the wins shows a strong correlation between the consistency in the speeds of the boats and the difference in finishing times.


Conclusion


Many factors helped New Zealand claim the 35th America’s Cup. Cyclors are cited as a key reason, as well as the excellent performance of the helmsman and tactician. Among it all though was a consistency with speed, maximizing the time spent at fly time. Having consistency in speed also helped with preventing accidents such as a capsize, which not only would lose the race, but could also severely damage the boat, or injure the crew. Overall, these factors led to New Zealand boasting a dominant 7-1 victory over the USA in the 35th America’s Cup.




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