Sailing with Science in San Francisco

The Swiss team Alinghi, holder of yacht racing's America's Cup, is heading to San Francisco for a week of friendly competition at the home base of arch-rival Oracle. A series of twelve races is scheduled to begin on Monday, September 15, in San Francisco Bay near the Golden Gate Bridge.

Most of each team's crew members who competed in the America's Cup races over this year in New Zealand will renew their rivalry in the west coast races. The competition format will feature three races a day, with the novel twist of the two yachts being guided alternately by their normal skippers in one race and by their owners in the next race.

Team Alinghi is based in Lausanne, Switzerland, at the Science Park of the Swiss Federal Institute of Technology in Lausanne (L'Ecole Polytechnique Fédérale Lausanne--or "EPFL" for short). As official scientific advisor to Alinghi since 2001, the EPFL has had four laboratories, 15 leading scientists, and some 20 students working with Team Alinghi in the research for their exceptionally fast racing yacht.

"Our partnership has provided a unique opportunity to apply immediately many of our basic research findings," explained Professor Jan-Anders Manson, head of the EPFL scientific team working with Alinghi. "In the ultra-competitive world of yacht racing, new technologies have at most about two years for research adaptation and implementation and perhaps another two years of practical service. Comparable times for automobile or aerospace industries, research and develop times are from 5 to 10 years, followed by some 12 to 20 years of practical service.". These extrem demands in high competions sport fields requires an highly dynamic implementation strategy of new technologies.

New Applications for Technology
EPFL's partnership has produced not only short-term success, but also defined major new areas for long-term research. Insights relating to water flow around the Alinghi hull, for example, can be applied to biomedical issues such as blood circulation in aortic valve replacements. Manson observed, "Years ago, a top aerospace executive on the west coast advised me to first apply important research findings to solutions in the sports field, where R&D can be quickly transferred to practical service. The resulting experience can then be part of more refined, long-term research for industries with high safety demands, such as medical care and aerospace."

Because a racing yacht like Alinghi uses the highest of high technology, there is hardly any field of engineering untapped in its design and construction. In capturing the ultimate prize of the America's Cup, Alinghi had to excel in all fields.

"That's why our collaboration with EPFL is so important," said Grant Simmer, design coordinator of Team Alinghi. "The broad and deep academic expertise of the EPFL helped us to evaluate our ideas quickly in such fields as materials science, structural resistance, and fluid dynamics."

Stress tolerance
Bertrand Cardis, director of the Swiss shipbuilding firm Decision SA and an EPFL engineer, explained that his company has worked closely with the EPFL for some 20 years. "EPFL people have constantly helped us to test our ideas and confirm our various structural designs. A good racing yacht must always conserve weight, so it must be built quite close to stress tolerance limits. That's why you see so many broken hulls and masts in this kind of racing. So we're very proud and happy that Alinghi had no important breakdowns in this year's America's Cup competition."

All in the keel
To improve shell performance, materials science experts tested the resistance of Alinghi's many assembled parts. Every ounce saved on the shell was shifted to the keel to improve speed and stability. The Alinghi boat weighs some 25 tons, of which 20 are in the keel.

Team Alinghi uses composite materials for the hull, mast, sails, and appendages. Together with the Alinghi team and Decision, EPFL's Composite and Polymer Technology Lab developed not only new composite pieces, but also new processing and testing procedures for optimal stuctural performance.

Water and air flow
Computer simulation was critically important in designing Alinghi below the water line as well as in the air. EPFL's modeling experts digitized the complex flow dynamics, while EPFL's Fluid Mechanics Lab developed detailed flow measurements for the underwater elements, the mast, and the rigging.

As material breakage is a constant threat in the extreme conditions of yacht racing, Alinghi's critical mechanical pieces were tested on a 1:1 scale in EPFL labs to insure their reliability. EPFL's Metal Construction Lab worked with design team engineers to improve the performance of these critical pieces and to establish maintenance plans for lubrication, inspection, and replacement.

The Team Alinghi sailors are confident in their boat's successful design and outstanding performance. Their careful research and development work with the EPFL paid big dividends in their America's Cup victory, all the while keeping within their comparatively modest budget.