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Geronimo back on the record trail soon

vendredi 7 juin 2002 –

The giant trimaran owned by Cap Gemini Ernst & Young and Schneider Electric was returned to her natural element in Brest harbour today.


Since returning from her attempt on the round-the-world record, Geronimo has been revised and updated down to the smallest detail. Once a season or after every major voyage, racing yachts return to the stocks in their boatyards for a Major Refit. Borrowed from the merchant and military marine, this term applies even to large vessels. Like them, Geronimo is a complex assembly of systems and structures requiring regular overhaul and refurbishment. Major Refit involves not only a general cleaning and painting of the hulls, but more importantly, dismantling all the boat’s systems and repairing or modifying all the faults or problems diagnosed.

The modifications and improvements made to Geronimo in her time ashore focus on three main areas : the rudder system, which has been the subject of much concern and many questions, the structure of the beams and hulls and the entire rig.

It was problems with the rudder blade that led to Olivier de Kersauson’s decision to abandon his attempt on the Jules Verne Trophy, and that have been the subject of lengthy and painstaking consideration, research and simulation. Every hypothesis has been examined, from ventilation to cavitation and the rigidity of the profile. Every specialist and engineer has been consulted, and Geronimo’s crew have been made only too aware that hydrodynamics remains a highly empirical science, in which every team has to feel its way forward with the greatest caution. This approach, which consists of taking however long is needed to understand a problem before acting to correct it, whilst reducing unknowns to the absolute minimum, has enabled a number of purely theoretical hypotheses to be eliminated. The first point of convergence between the studies conducted by the various parties involved the rigidity of the profile, which has been considerably increased. The second point of convergence seems a logical extension of the first, and concerns the design of the profile itself, which will be less radical and more tolerant than before.

All structural hot spots have been ultrasonically tested and every key structural calculation has been reworked using the actual stresses and problems encountered. Over thirty engineers and technicians have worked on Geronimo over the last eight weeks in an attempt to resolve over a hundred specific instances of wear, stress or unexpected behaviour. After travelling 25,000 miles (the same as a circumnavigation) and suffering at the hands of March’s deep depressions, Geronimo would have needed this general overhaul anyway. The giant trimaran pays the price for her raw power and exceptional size by being subject to stresses that are difficult to simulate and even harder to predict, forcing all those involved to proceed step by prudent step in a laborious process of eliminating hypotheses.

Information : http://www.grandsrecords.com

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