Vendee Globe and Alex Thomson / Hugo Boss

dom

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Quick background point from one of the French teams this morning -- perhaps interesting to some:

These vessels have all been designed by 'expert' design teams, but expert in this sense means the use of theoretical frameworks calibrated in imperfect empirical data. Pure theoretical models are not possible to fully constrain as there are simply too many variables.

For which reason the testing of, for example, aircraft wings involves a ton of calcs, myriads of expensive sensors, and extensive mandatory stress cycles. In terms of boats, designers should really apply 3 load calcs/tests: maximum normal load limits, ultimate load specifications, and finite element model calculations (FEM). Is this done in practice? (i) and (ii) are, but (iii) is not.

Because FEM testing returns us to the problem of models need be calibrated and validated empirically, which implies testing samples and test mock-ups to destruction under controlled environments. This doesn’t happen with pleasure boats and there simply isn't the data for cutting-edge vessels. Not through any fault of the designers, because a detailed knowledge of the materials is necessary and laminates are still not rigidly controlled enough and are subject to too much human error and variance to accurately model in the ultimate stress sphere.

In fact, the strength and characteristics of laminated hulls can vary widely within the same production line. Not to mention the changes in dynamic loading that could have been brought about by the reinforcement and design retrofitting applied to both HB and PRB.

NOBODY is blaming anyone here, such is the nature of budget-constrained pioneers, but there's something going on here and other competitors with similar boats are taking note.

Here's wising everyone a safe journey from here on in. As for "Yes we Cam!"
....it seems like you truly Cam!! :)(y)
 
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Kukri

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We have to hope that the aftermath of this rescue is a little bit less acrimonious though...
PRB may sue for cost of rescue - Yachting World

"Ah, Mr PRB, how lucky to find you in this life raft, now before we begin the rescuing, please sign this waiver..."

Oddly enough racing yachts are not covered by insurance for the costs of rescuing someone, but merchant ships are - as they are also covered for the costs of picking up refugees found at sea - under their P&I Club entry.
 

flaming

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I am beginning to wonder if Theta caused underlying damage to both PRB and Hugo Boss + maybe others. They took one hell of an upwind bashing in the North Atlantic.
They were going downwind around Theta. The upwind stuff was into the front that came through about 48 hours into the race. And was not at all unusual vs previous races.

My initial thoughts re PRB are that it is being reported as folding when it ploughed into a wave at 27 knots. It was not originally designed for foils, they had been retrofitted. It was also very light, and had done a lot of miles. So I wonder about a combination of material fatigue, loads that exceeded the original design loads for the structure caused by the foils, and the rather extreme load case of burying the bow at 27 knots.
 

kof

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Good update Vendée Globe rescue: Le Cam plucks Escoffier from mid-Atlantic liferaft (yachtingworld.com)

"Speaking from onboard Le Cam’s boat Yes We Cam!, Escoffier described the moment the boat literally folded in half before he had to suddenly abandon ship: “You see the images of shipwrecks? It was like that, but worse.

“In four seconds the boat nosedived, the bow folded at 90°. I put my head down in the cockpit, a wave was coming. I had time to send one text before the wave fried the electronics. It was completely crazy. It folded the boat in two. I’ve seen a lot before but this one…"
 

st599

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They were going downwind around Theta. The upwind stuff was into the front that came through about 48 hours into the race. And was not at all unusual vs previous races.

My initial thoughts re PRB are that it is being reported as folding when it ploughed into a wave at 27 knots. It was not originally designed for foils, they had been retrofitted. It was also very light, and had done a lot of miles. So I wonder about a combination of material fatigue, loads that exceeded the original design loads for the structure caused by the foils, and the rather extreme load case of burying the bow at 27 knots.

I think I'd read somewhere it had recent repair work after a crash near St Malo.
 

NormanB

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I strongly suggest that Ravi has not been in a life raft for any length of time, or in any poor sea state.(n)
Have you ever been in a life raft?
Physically 11 hours in a liferaft in any sea state is pretty tough.
The psychology just amplifies that.
 

Ravi

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I strongly suggest that Ravi has not been in a life raft for any length of time, or in any poor sea state.(n)

My point is simply that a modern life raft should be a secure, (albeit traumatic) place to be for 24 hours in those conditions.

I.e. they should not sink or remain inverted.

I also made the point that being out the wind in 11 degrees c, in a dry survival suit, is unlikely to result in hypothermia.

I am not sure why either of those statements are contentious.
 
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On one hand we have lightweight, hi speed sailing yachts racing in oceans coming to grief and on the other we have heavier, slow sailing yachts racing in oceans coming to grief. Then again, we also have both styles successfully sailing and racing in oceans without coming to grief. It is just the way it is, tough conditions increase the probability of failure, yet the majority sail onwards to the finish. Sad, but hardly unexpected that some will fail to finish the race.
 

kof

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Great interview with Kevin on what happened. They used a drift analysis program from Meteo france to predict the drift of the liferaft, passed this on to LeCam over a Skype call and he said ok, I'll go that way. Shortly afterwards they found Kevin E.

Good job by all.

 
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Frogmogman

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It seems that the plan is for Jean le Cam to rendez-vous with the French Navy frigate Le Nivose to the North of the Kerguelen Islands on December 7th to transfer Kevin Escoffier into the hands of the French Navy.
 

Sandy

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It seems that the plan is for Jean le Cam to rendez-vous with the French Navy frigate Le Nivose to the North of the Kerguelen Islands on December 7th to transfer Kevin Escoffier into the hands of the French Navy.
Considering there was a 'fly by' with TV pictures last time I wonder if the French Navy position a frigate in the area for the race or just happened to be in the area.

If they do position one there that is very sporting of them.
 

cherod

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I strongly suggest that Ravi has not been in a life raft for any length of time, or in any poor sea state.(n)
well , interestingly , Kevin was not particularly bothered about spending the nite in the life raft , nor was Le Cam at leaving him there until conditions for the transfer improved .
 

st599

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It seems that the plan is for Jean le Cam to rendez-vous with the French Navy frigate Le Nivose to the North of the Kerguelen Islands on December 7th to transfer Kevin Escoffier into the hands of the French Navy.
Does he get more food handed over, they seem to be a bit light on rations to begin with (no beer or rum), so having an extra person to feed for a week must be a bit damaging to stocks.
 
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