The world's fastest sailing boat uses HBM measurement technology
"Flying" over the ocean with a boat requires innovative materials and technologies. The French sailor Alain Thébault relies on HBM measurement technology for evaluating potential load limits during the development of his trimaran "Hydroptère".
Alain Thébault has pursued a single target for over 15 years: He wants to build the fastest sailing boat ever; he literally wants his boat to fly.
World record in the Mediterranean
September 04, 2009: Alain Thébault and his crew are sailing the 18.28 meter long trimaran "Hydroptère" at high speed, off the Mediterranean coastal town of Hyères in southern France. The wind conditions are favorable, not overly strong but stable. The hydrofoils slice through water, which is as hard as concrete at such speeds, while the hull is elevated several meters above the surface of the water. The Hydroptère is winging its way over the water at an average speed of 51.36 knots (95 km/h), thereby breaking the absolute world speed record for a sail-powered vessel. The previous best of 50.57 knots was set by kite surfer Alex Caizergues in 2008. To qualify for the world record, a distance of 500 meters has to be covered.
To attain such high speeds, Alain Thébault's team had to reduce the drag of all components affecting aerodynamics and to optimize the design and control of the sails. The main challenge, however, was to develop hydrofoils providing sufficient lift without causing water turbulence. For this reason, only innovative and advanced materials were used in the design of the Hydroptère; this becomes obvious when looking at the price of the mast which cost Euro 400,000. The struts of the boat are made of titanium, the sails woven from carbon fiber. The hydrofoils originate from the Airbus factory in Nantes, and the suspension of the hydrofoils – inspired by the landing gear of an aircraft – must withstand a pressure of 45 tons.
Advanced technology platform using HBM measurement technology
However, the Hydroptère is not only an ultra-fast trimaran made from innovative materials. It is also an advanced technology platform – using HBM measurement technology installed on-board for improving and developing the concept. The Hydroptère is, therefore, also a laboratory ship for researching the specific features of a trimaran: Stability, speed, cavitation, drag, vibration and oscillation as well as the wear of the materials used.
Real-time load measurement
The measurement system enables the sailors to carry out real-time analyses of the loads affecting the boat. Engineer Damien Colegrave is responsible for the complete monitoring and data acquisition during each test. Visual and acoustic signals warn immediately as soon as a strain limit is exceeded and thus enable Damien Colegrave to react as required. After each test, he carries out a complete analysis of the recordings to draw conclusions from the boat's responses to swell, wind, and orientation of the sails. In addition, the results are compared to the calculations provided by the Hydrop6 flight simulator which enables engineers to predict the trimaran's theoretical behavior more reliably.
Strain gages are indispensable for development
Damien Colegrave says about the use of measurement technology: "The strain gages and the transmitted data were a prerequisite for calculating and designing the main components of the boat, especially the transition pieces between boom, hydrofoils and hull. For this reason, we have focused on the strain gages – their protection and the use of the data they provide. This is essential to a project like Hydroptère, because it is a prototype for which no empirical values regarding the potential loads are available at all."
"Expectations on measurement technology were fully met"
Damien Colegrave continues: "We installed our latest CANbus-based measurement system in 2006 after comparing many suppliers with each other. We chose HBM. The digiCLIP digital, modular amplifier fully met our expectations - it is compact, light-weight and extremely robust. And, above all, it is very easy to use. HBM service engineers expertly installed over 40 full bridges and protected them against external influences using appropriate materials. The digiCLIP amplifiers as well as the strain gages have now been on board for three years. They have withstood high speeds attained in sea water as well as the strong vibrations without any problems."