"It's about finishing the race."
"It's about finishing the race."
Photo: C.Launay/ Alex Thomson Racing/ HUGO BOSS
“It’s about finishing the race.”
Caterham Composites provides the design and structural engineering of the emergency rudder concept, for the IMOCA 60 yacht of Alex Thomson Racing.
Marine, Offshore Racing
To design a lightweight fix for a broken rudder, giving the skipper the opportunity to sail to safety, and complete the race, without assistance.
A lightweight rudder sleeve that fits over the broken section, and provides the same hydrodynamic qualities.
A simple solution that is saves weight and is easy to use, delivered on time and on budget.
Broken Rudder - Photo by Alex Thomson Racing
The Vendée Globe, founded by Philippe Jeantot in 1989, is a round-the-world, single-handed yacht race. The race is sailed non-stop and without any assistance for approximately three months. The Vendée Globe starts in Les Sables d’Olonne, France taking the skippers to the Cape of Good Hope, around Antartica, and back to Les Sables d’Olonne Cape - Leeuwin and Cape Horn are the only ports for the participants. For Alex Thomson, the Vendée Globe is about finishing the race. “For me - personally I have to finish this. That is what it is about - finishing.”
The emergency rudder is designed to give Alex a lightweight, easy-to-install method of steering the boat, without requiring any external assistance, which would allow him to sail to safety or even finish the race.
ATR’s yacht is one of the fastest in the world and extreme pressures are put onto the rudder even in normal sailing conditions. During his race around the world, Alex will encounter extreme storms and huge waves plus the ever-present danger of floating objects in the water. There is a real risk of damaging or breaking a rudder. This would leave Alex in a potentially dangerous situation and so a solution is needed. An entire replacement would weigh 20kg and be very difficult for Alex to fit whilst at sea and on his own.
The concept is a development of something ATR trialled and used in a previous race with some success. We were given the brief to design a rudder that would fit over whatever remained of the standard rudder, and allow Alex to sail at 75% of full performance to the finish. The sleeve had to be as light as possible and match the hydrodynamic characteristics of the existing rudder.
The solution is a sleeve that fits over the remains of the rudder and matches the hydrodynamic performance of the rudder and its structural strength and stiffness. The original rudder is comprised of the outer profile and a stock to transmit the torque and to provide stiffness. The emergency rudder sleeve must do the job of both in one structure.
We had recently performed a structural review of the rudder and stock on the yacht, and therefore had a good knowledge of the loads already. During past discussions with ATR on the previous use of this concept we managed to agree on how to model the load cases. The next challenge was to define the performance available to Alex when this emergency system was in use. We created the 3D model and designed a baseline laminate. One of our engineers then took this model and base laminate and, using HyperWorks, optimised the patch sizes, orientations, thicknesses and the order of these to provide the lightest solution.
The rudder we developed is an emergency system and not a racing system. We knew that the performance would be below 100% and thus, would be a trade off between weight and performance. By using HyperWorks optimisation, we achieved the perfect balance.
The result is a hydrodynamic structure that provides the strength and stiffness required for Alex to still be able to push the boat but at a weight of only 9 kg. This is a 10% reduction in weight on the base laminate whilst also being 23% stiffer and 72% stronger.
About Caterham Composites
We believe that creative thinking and engineering rigour can make anything lighter, stronger, faster and more efficient. Part of the Caterham Group, we’re a specialist company delivering turn-key lightweight structural solutions to all industries. We offer fresh thinking, new perspectives and an unquenchable thirst for improvement. Our focus is on the aerospace, automotive, marine, and motor sport industries - including Formula One, the leading sector for structural lightweight solutions and applied technology.
Our unique experience, spanning more than 25 years, combined with groundbreaking technology and a free-thinking environment means we can deliver tailored innovation for our customers.
About Alex Thomson
Alex Thomson is the youngest skipper ever to win a round the world race, claiming victory in the 1998/99 Clipper Round the World Race; a record he still holds today. Alex then launched onto the solo racing scene with a bang, breaking the world distance record in 2003. However his first two solo round the world attempts were met with frustration when structural failure of his yacht forced him to retire early from the Vendée Globe 2004 and Velux 5 Oceans Race 2006
In November 2011, Alex completed the Transat Jacques Vabre double-handed race from Le Havre, France to Puerto Limon, Costa Rica, securing another 2nd place podium finish. He is now even more determined to achieve his dream to become the first Briton to win the Vendée Globe, which begins in Les Sables d’Olonne on 10 November 2012.
Altair Engineering, Inc. empowers client innovation and decision-making through technology that optimizes the analysis, management and visualization of business and engineering information. Privately held, with more than 1,500 employees, Altair has offices throughout North America, South America, Europe and Asia/Pacific. With a 26-year track record for high-end software and consulting services for engineering, high-performance computing and enterprise analytics, Altair consistently delivers a competitive advantage to customers in a broad range of industries.