Monday, 23 November 2009

Jules Verne Trophy: Explanations from Franck Cammas

by Vincent Borde and Caroline Muller

17th November 2009

Over the past 24 hours, 16-17 November, the crew of Groupama 3 has been working together to contain the damage suffered around the beam bulkhead. The maxi trimaran has also had to let the Brazilian low pass over the top of her, which created strong winds last night... Franck Cammas looks back at the past few hours in the middle of the Southern Atlantic.

What is your current situation?
"We're flirting with the centre of a big low, which has pushed us towards the Cape of Good Hope. However, a secondary low has formed over the cold front, with wind which can very quickly increase to 60 knots! As such we've taken refuge not far from the centre of the big low to let all that get past us. This is why we spent the whole night barepoled, heading due South. Since 0200 UTC this morning, we've been able to hoist more sail aloft as conditions have become more manageable. At the end of the afternoon we're set to gybe and make headway eastwards towards Cape Town, by remaining at the rear of the worst of the bad weather. There will continue to be a swell and big seas and there's still some debate as to how to handle the boat so as to prevent her from suffering. We won't be taking any risks, even if we have to stop..."

How is life on board being organised?
"Everyone is busy with their own tasks: the lamination specialists (Lionel Lemonchois assisted by Thomas Coville) have been working throughout the night. We're all disappointed but we're already casting our minds to the future. We're going to try to get Groupama 3 back to Brittany as fast as possible. When we decided to abandon the record attempt it came as a harsh blow: we went from a performance configuration to a simple delivery. It's not the same life aboard, the atmosphere isn't the same and the time seems to go by a lot slower. Fortunately we've got some books on board to be able to escape a little when we're not helming..."

Do you have an explanation for this damage?
"We think that the stresses and motion of the float are the cause of it. There are always some interference effects which are difficult to model on a computer though. The waves never strike the boat in the same way and the platform is subject to some disorganised behaviour: there are some extremely violent vibrations in a chaotic sea. We think that the float has been able to ripple longitudinally with a series of waves on the stern, whilst the support level with the beam is very rigid. At that stage, the bulkhead cracking was the pivotal point in this scenario..."

What is the extent of the damage?
"The breakage isn't spectacular, but we know things could deteriorate very quickly and impact on the structural integrity of Groupama 3. It's worrying and will force us to make a technical pitstop, but it's a lot less serious than the last time... The bulkhead which extends along the beam by entering the float has split open: We've had to install two braces to maintain the separation between two sections of the bulkhead, and then insert some foam before sticking it back together. Right now the bulkhead has been stiffened. However, we still have a problem with it as the bulkhead has caused the skin inside the float to become detached across an area of around 400 mm. For the time being we haven't succeeded in sticking the float to the bulkhead so it's moving with every wave. We have to hope that the UDs (unidirectional materials) which stiffen the base of the float don't break, because that section is the float's backbone! As such we're going to have to find a way of joining the whole periphery of the bulkhead to the float."

What are your objectives now?
"We're going to have to reinforce the four beam attachments but first of all we're going to have to carry out a thorough analysis with the engineers and architects. We certainly won't be able to set off on a round the world without trusting in the repair and without knowing the reasons for this damage. It's not 100% certain we'll be able to set off again at the end of January. However, given that we left Ushant very early on, there is still a chance we can set off again before the season draws to a close. It's feasible! We're going to have to be happy with Groupama 3's capacity to sail around the world though..."

What are the options over the coming days?
"We'll get to Cape Town by 22nd November at best, or by 24th November at the latest. There is also a third option, which is to make straight for Lorient if the repairs we make at sea are satisfactory. This would save us a lot of time in our bid to get going on another attempt at the record. Currently there is no danger of the mast falling as it's fixed onto another bulkhead and we've even been able to hoist the sail again, making 17 knots with the right angles to the wind and the seas..."

Cammas - Groupama

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