Repairing damage to the giant trimaran Groupama 3 amounts to most of a new build
On the subject of extensive repairs, I visited French builders Multiplast a few weeks ago and saw the work being done to repair the 104ft trimaran Groupama 3. She broke up off New Zealand earlier this year while attempting to break the Jules Verne record for the fastest time round the world.
The scope of the work needed shows just how a ‘one little crack’ type of problem can spread and propagate until it ends in major failure that needs a serious rebuild to put right.
Groupama 3 had been 2,000 miles ahead of the record when the port float tore off. The forward port beam of Groupama 3 cracked and the whole port float broke away between the forward beam and the foil.
Designers VPLP say they aren’t yet 100% sure of the root cause but the hypothesis is that the port side suffered from a lot of wave impacts during the long period that the trimaran was sailed on starboard tack.
Luckily being so close to New Zealand most of the parts were salvaged after the crew were rescued, but some seven months later the boat is still being rebuilt. Designer Capucine Cadiou from VPLP estimates that the work amounts to “three-fifths of a new build”.
The repairs involve completely rebuilding two new floats which are now monolithic carbon on the outboard side between the two beams instead of sandwich construction. They also have extra stringers and bulkheads to cope with torsional loads.
The beams are being rebuilt to the same design. The problem there was that some of the bolts along the aft face had fatigued and there was delamination at the point of maximum curvature.
It’s still expected that Franck Cammas, currently busy with the BMW Oracle trimaran, will have another crack at the round the world record early next year.