Are 60ft trimarans unseaworthy?

The Daily Sail got the views of leading trimaran designer Nigel Irens

Interestingly it was in both instances the weather float - supposedly flying out of the water - that was damaged. "If the outside hull is slammed downwards at the same time as a wave is breaking against it, who knows what the forces are there? But I have to say that we have never had an outside hull break between the beams before. We’ve had about nine bows have broken off from my boats over the years. Now we’ve had that, that doesn’t happen anymore but no one has been in a situation where the middle of the float is as badly subject to these big loads."

Irens says that the floats broke simply because they were not adequately engineered to survive the severe conditions. "I think it is probably because there’s not enough material there because no one has really had the problem before and no one has had to learn from a previous situation and make it stronger there."

Irens suspects that one of the general problems with the new generation of boats is the use of higher modulus fibres used in the construction of the platform and the mast. "We generally feel that what is happening with the masts – and what has happened now may or may not confirm that - is that we feel it is possible that the rigidity of the materials we’re using now and the lack of elasticity is attracting loads we haven’t seen before and there is no shock absorpsion. So we may need to review that and go back to materials even that are more inclined to…

"One of the problems with lightweight structures like Nomex/carbon is that if you do start to get the beginning of a failure you don’t get a second chance. It just unzips itself like a banana skin. Whereas with some of these more lowtech materials, particularly I’m thinking like a linear error, like good old spongey Airex it is more designed to accept shocks. It is something which is bubbling up. And that might be something to do with the fairing problems.

"Every time we put a material into the fairings that is high modulus, we’ve had problems and every time that we go back to Airex that fails at similar loads to Nomex, but it can be subject to a lot more deflection before that load is reached.


So are the new boats more dangerous? Irens feels not. "The skippers are generally saying that they feel more secure and more at ease on these bigger newer boats than the older ones. They feel more in control. So the extremity of the boats is not the problem." This has been independently confirmed to The Daily Sail by several of the trimaran skippers. Also untrue is that the boats are lighter and more flimsy than before.

"The impression is that the boats are getting lighter and lighter and that isn’t the case," says Irens. "And also I can confirm that no skippers have asked us to reduce margins and similarly we haven’t asked an structural engineers to reduce margins on what they did before. So the explanation is not that one." If anything with the new more complex foils, transom hung kick up rudders, bigger cockpits and more winches, the boats have got considerably heavier.

"It is unfortunate for us that the thing which failed with us is something which is likely to cost the boat, certainly in Fuji’s case. They’re down there now trying to pick up the pieces."

There are mumbling in the 60ft trimaran class that singlehanding is not as popular as it once was. Irens believe the skippers are divided about this. "I think some people still feel very sentimentally attracted to the whole notion, objective and principle of the Rhum and others not so. I think it depends how keen you are on singlehanded sailing. I don’t think there is anything to do with the boat itself that makes it disadvantaged by singlehanded sailing except that in very extreme conditions you may get away with it if you were able to stay on the helm 100% of the time and you can’t singlehanded - if it just drifts off by a couple of degrees and starts to set off and changes the apparent a bit, then it could be over before you know it."

He also believes that there is a faction who believe that changing the date of the Route du Rhum would not make it the Route du Rhum. "The difficulty is the marketing end of the Route du Rhum is based around the notion that you start in hell and come out in paradise."

Clearly whether it is fault of bad timing by the organisers, high modulus materials, expected forecasts, the 60ft trimaran must get their house in order and stop breaking boats or risk having sponsors pulling out in droves.

What do you think about the trimaran carnage? Email your thoughts to feedback@thedailysail.com