These things are insane. How physically and mentally demanding is the Vendee going to be on one of these.
Tried to attatch a vid but dosnt want to do it. Google Imoca Charal if you are interested.
Thanks AzureF305. That's an old one. They have just relaunched her with new foils and other mods.
I know, I can't imagine being switched on for such long stretches of time on such twitchy powerful beasts. I know they mostly sail them on autopilot once they're set, but still, it must be absolutely exhausting. And there's Alex Thomsons little dingle with Guadaloupe near the end of the Route du Rhum, to press the point. He was knackered and asleep. I'm really looking forward to the Vendee start!
A lot of the older foiling hulls have had updated foils added too, it's going to be a fast race.
Yep, the noise must be incredible. One of the features in the last race was an interview with the race doctor. He said that it's a fairly constant 120 dB inside the hull as it's carbon fibre. Most skippers "sleep" with noise cancelling headphones on.
Select to expand quoteSandS said..
looks like the rudder and associated bits will take big hits !
I think I read that some boats are carrying spare foils this time. No idea how you'd change one in big seas. Last time Thomson broke one off (shipping container I think) and was fast on one tack and slow on the other without the foil. Amazing boats.
120dB.... man! that's a chain saw at full tilt less than one meter away, I'd be wearing my noise cancelling headphones the whole time.
Select to expand quote2bish said..
120dB.... man! that's a chain saw at full tilt less than one meter away, I'd be wearing my noise cancelling headphones the whole time.
I slightly exaggerated. It varies between 90 and 120 dB: www.vendeeglobe.org/en/news/16517/ear-flaps
Still very unpleasant.
I often wonder if the Volvo boys look at the Imocas and grind their teeth for the Imoca's traits on protection from the elements. I get that you can't do this on a fully crewed boat, but man, I know which one I'd rather do the Southern Ocean in.
And if you ever needed justification for a three point tether with a short strop....
That toe rail looks awfully important all of a sudden!
Select to expand quoteshaggybaxter said..
And if you ever needed justification for a three point tether with a short strop....
That toe rail looks awfully important all of a sudden!
Absolutely. Interesting how the foredeck is as clean as possible to allow water to run off, lightening the bow. Also not a deck-sweeping foot on the jib as there must be a sweet spot where not catching water is more important than sail area.
Select to expand quoteshaggybaxter said..
I often wonder if the Volvo boys look at the Imocas and grind their teeth for the Imoca's traits on protection from the elements. I get that you can't do this on a fully crewed boat, but man, I know which one I'd rather do the Southern Ocean in.
There was an interview with David Witt I saw. They asked him Volvo or Imoca. He said Imoca. Going around the world on a Volvo boat is like someone spraying you with a fire hose any time you go on deck.
The Corum boat is launched now and there are some great articles about it. It's very different again. Scow bow. The foils are quite high on the top sides too.
Select to expand quoteRamona said..
I believe the noise inside is what causes the most stress and exhaustion.
On a delivery trip of a carbon-fibre hull SH boat, for about a day we were running regularly topping 20kn (boat speed) and coming off 4-5 m breaking waves. Helming was exhausting but fun, but being off-watch was an appalling experience due to the incessant loud crash-bang noise, and the incredible jolting jarring and vibration. I can't imagine how those crews endure weeks of that.
I love my nice semi-full keel 55% ballast ratio, 14 SA/D old man boat!
Cheers, Graeme
Select to expand quotewongaga said..
I love my nice semi-full keel 55% ballast ratio, 14 SA/D old man boat!
Cheers, Graeme
Just keen to learn here ... What is a semi-full keep 55% ballast ratio, 24 SA/D?
Does it get planing? Wouldn't it be nice to get planing, switch on the auto-pilot and enjoy the ride with a beer?
Select to expand quoteJakeNN said..
Does it get planing? Wouldn't it be nice to get planing, switch on the auto-pilot and enjoy the ride with a beer?
Probably a better question for ShaggyB!
Select to expand quoteJakeNN said..wongaga said..
I love my nice semi-full keel 55% ballast ratio, 14 SA/D old man boat!
Cheers, Graeme
Just keen to learn here ... What is a semi-full keep 55% ballast ratio, 24 SA/D?
Does it get planing? Wouldn't it be nice to get planing, switch on the auto-pilot and enjoy the ride with a beer?
Think of a 1970's 4-cylinder Volvo station wagon as compared to a F1 racer.
Select to expand quoteJakeNN said..wongaga said..
I love my nice semi-full keel 55% ballast ratio, 14 SA/D old man boat!
Cheers, Graeme
Just keen to learn here ... What is a semi-full keep 55% ballast ratio, 24 SA/D?
Does it get planing? Wouldn't it be nice to get planing, switch on the auto-pilot and enjoy the ride with a beer?
Hi Jake,
The ballast ratio is a percentage of the ballast compared to the dry weight. The higher the number, the more ballast is carried compared to the overall weight, which means more resistance to heel. Graeme's 55% compared to my 36% means as the weather gets a bit fresh Graeme is enjoying a nice cup of tea with full sails up as I am scrambling to downsize sail area to keep the boat on her feet.
The SA/D is a comparison of your total sail area to your displacement. Upwind I run a SA/D of 34'ish, downwind it jumps to about 65. Graeme's SA/D of 14 means as the weather gets fresh he is now enjoying a nice nap after his cup of tea, still with full sails up, as I am hanging on grimly as the boat charges off like it's been possessed . We start planing at about 15kn TWS and as the wind comes behind about 80 deg TWA.
To answer your question, yes its the best feeling in the world to sit back when the boat is trimmed, on the plane and it' s effortlessly soaking up miles. For Fusion, the lower ballast ratio is offset by a wider beam which lends a lot of hull form resistance to heeling, so gusts tend to be soaked up by the hull shape rather than put you over on your ear. That sort of thing isn't reflected in your SA/D or Ballast ratio, which is why there is a bazillion other calcs naval architects use to typify a boats manners.
So while a higher SA/D is enormously rewarding, you can't be lazy. Speed is fun, but if the comfort level goes way down to achieve this it gets a bit naff pretty quickly.
To apply this to the real world... Graeme and I are headed for same harbour and its been a bit fresh. Graeme may get their a tad later but he'll be dry, comfy, sporting a big smile and a hairstyle like he stepped out of Vogue magazine. I might get there a bit quicker, but I'll be soaked, tired, counting bruises, sporting a HUGE smile and a hairstyle like I stepped out of Just Mechanics.
Cheers!
SB
Select to expand quoteshaggybaxter said..JakeNN said..wongaga said..
I love my nice semi-full keel 55% ballast ratio, 14 SA/D old man boat!
Cheers, Graeme
Just keen to learn here ... What is a semi-full keep 55% ballast ratio, 24 SA/D?
Does it get planing? Wouldn't it be nice to get planing, switch on the auto-pilot and enjoy the ride with a beer?
Hi Jake,
The ballast ratio is a percentage of the ballast compared to the dry weight. The higher the number, the more ballast is carried compared to the overall weight, which means more resistance to heel. Graeme's 55% compared to my 36% means as the weather gets a bit fresh Graeme is enjoying a nice cup of tea with full sails up as I am scrambling to downsize sail area to keep the boat on her feet.
The SA/D is a comparison of your total sail area to your displacement. Upwind I run a SA/D of 34'ish, downwind it jumps to about 65. Graeme's SA/D of 14 means as the weather gets fresh he is now enjoying a nice nap after his cup of tea, still with full sails up, as I am hanging on grimly as the boat charges off like it's been possessed . We start planing at about 15kn TWS and as the wind comes behind about 80 deg TWA.
To answer your question, yes its the best feeling in the world to sit back when the boat is trimmed, on the plane and it' s effortlessly soaking up miles. For Fusion, the lower ballast ratio is offset by a wider beam which lends a lot of hull form resistance to heeling, so gusts tend to be soaked up by the hull shape rather than put you over on your ear. That sort of thing isn't reflected in your SA/D or Ballast ratio, which is why there is a bazillion other calcs naval architects use to typify a boats manners.
So while a higher SA/D is enormously rewarding, you can't be lazy. Speed is fun, but if the comfort level goes way down to achieve this it gets a bit naff pretty quickly.
To apply this to the real world... Graeme and I are headed for same harbour and its been a bit fresh. Graeme may get their a tad later but he'll be dry, comfy, sporting a big smile and a hairstyle like he stepped out of Vogue magazine. I might get there a bit quicker, but I'll be soaked, tired, counting bruises, sporting a HUGE smile and a hairstyle like I stepped out of Just Mechanics.
Cheers!
SB
Good writing SB - got a kick out of reading it
Select to expand quoteshaggybaxter said..
To answer your question, yes its the best feeling in the world to sit back when the boat is trimmed, on the plane and it' s effortlessly soaking up miles.
I have had a short planing experience on a 50ft yacht and I have to agree it was amazing ... a similar amazing feel to windsurfing.
Thanks SB ... I have got so much to learn!
So planing on a 50 ft knot is not really as easy as it looks on youtube! 
hmmm .. and I'm sure it doesn't come cheaply either!
