The SSPA received a special visit this week as two Swedish sailing teams came to test their foils, for the second time. The focus is on a special measurement method developed by the SSPA and Chalmers – which has already proven successful for sailing teams.
“We have taken a big step forward in our sailing this year and now we have our sights set on the Paris Olympics in 2024 and then the Los Angeles Olympics in 2028,” said Swedish national sailor Ida Svensson. at the Olympic games. NACRA class 17.
We ended up at SSPA, the maritime research and ship-testing facility now owned by RISE and located on the Chalmers campus. From the outside, a fairly discreet brick building. But inside – among huge tanks, workshop halls and laboratories – marine research at the highest level takes place.
“As the hydrofoils, like wings, lift the hull of the boat and make the boat “fly” above the surface of the water, the resistance is reduced by up to 80%. Less drag means longer range for a battery-powered vessel,” says Arash.
Speed increase up to 50%
It also means that boat speed can increase significantly. A phenomenon that sailing has already discovered. In recent years, hydrofoil technology has revolutionized the sport, where sailors today reach much higher speeds than before. The research taking place at SSPA and Chalmers is therefore of great interest to the competitive sailing community. And Laura’s interest in hydrofoils is far from accidental.
In her role, Laura technically advises the Swedish national sailing team in four different classes. One of the teams is made up of sailors Ida Svensson and Marcus Dackhammar and today they visit the research center to, with the help of Laura, carry out advanced measurements on their hydrofoils in the hope of optimizing their navigation .
For three years, the team competed together in the Olympic NACRA 17 class, that is, a 17-foot-long catamaran fitted with foils.
“I’m the helmsman and Marcus is the one pulling the ropes,” Ida explains.
The Olympic class has been in development for a few years and has now completely transitioned to the use of foils. And there is no doubt that hydrofoils make the difference:
“Previously we only foiled the downwind, but with the new rudder system introduced after Tokyo 2020, we can now also fly upwind, so against the wind, which means an increase in speed of around 10 – 11 knots to around 15 knots. In other words, an increase in speed of almost 50%,” says Marcus.
The search for the right degree of rigidity
“We are here to measure the stiffness of the rudders and the daggerboards, which play an important role in the acceleration of the boat,” explains Marcus. And Ida fills in:
“The faster we go, the more important it becomes to have the right equipment. NACRA is a catamaran, and if we know which way we sail the fastest, then we can know what degree of stiffness translates into the fastest speed.
At the center of attention in today’s foil testing is a measurement method that allows the stiffness of foils to be studied at a detailed level and how they are affected if, for example, load or speed increases or when the positioning of the sheet changes.
In the lab, the sheets are “put into place” in a device and weights are attached to increase the load. Three advanced cameras document even the smallest changes in the hydrofoil and send the data directly to a computer where Marcus, Ida and Laura can see the results in real time, both in numbers and in 3D illustration.
It’s a great balancing act. The stiffer the hydrofoil, the higher the boat “flies” and the speed increases. But if the boat flies too high, the foils start to vent, which can lead to a sudden loss of speed, flapping and the risk of injury.
“We tested a range of foils that had a 15% difference in stiffness and we can see that is a factor that makes the difference. Then, of course, it is difficult to exclude other factors, such as the waves, the water temperature or our behavior on the boat, it is the human factor, which can also influence navigation”, explains Marcus.
“We have taken a big step forward”
Marcus and Ida have already noticed that lab measurement pays off in their navigation. This is not the team’s first visit to the facility:
“We were here last spring and tested the foils we had then. Now we have purchased new equipment that we would like to test. During this year, we have taken a big step forward in our sail and now our eyes are on the Paris 2024 Olympics and then the 2028 Olympics in Los Angeles,” says Ida Svensson.
Although the tests that may be carried out at the SSPA can be considered somewhat unique, it is highly likely that other nations will also carry out similar tests on their foils. But exactly how is shrouded in darkness.
“We can’t get this data anywhere else. Thanks to Laura, we can relate the research done here to reality. It is very likely that our competitors in other countries are also testing, but no one wants to share what technology they are using or what the results look like,” says Ida.
Once Ida and Marcus have finished their tests, a longer training trip to Lanzarote awaits them this winter, where they will also have the opportunity to compare the results of today’s measurements with the performance of the foils in the water. The competition season starts in April and the Paris 2024 Olympics are looming.
“At the moment, we are between 12th and 18th in the world in our class. There are 19 countries participating in the Olympics, so first we have to get a place in the selection,” says Marcus.
And if all goes as planned, Laura and her airboat research will follow the team for years to come.
“I will continue to help the Swedish sailing team until the Olympics in Paris in 2024 and hopefully until the next Olympics in Los Angeles in 2028,” says Laura.
Text: Lovisa Håkansson