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      Abbreviated rules   07/28/2017

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LeoV

Jules Verne Trophy 2016

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I am following it in silence, this is so out of my experience level, I can not find anything to say other then, awesome...

 

 

:)

+1

 

I'm just back from Brittany and it was great the coverage these guys and the Vendee boys get. Leading tv news article for Colville for three nights in a row.

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Stunning performance to keep the boat at these speeds for so long.

 

I wonder if the WSSRC keeps records for the greatest distance in one week - these guys would have smashed that one.

 

Yes, its velocity along the course. (I assumed that was obvious...sorry)

If you do a linear trend line on all VMC data since they started its nearly flat and has only changed +1.1% since the start.

Greatest distance in a week is 4327.27 nm, Graph below, x-axis is distance from the finish and obviously starts 1 week after the start.

post-41572-0-07473200-1483536715_thumb.jpg

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Well at least we are getting some action with the low forming right after NZ. No clue how they can jump into that. Well, it is almost 10 days making 800 + miles they have to stop at some point.

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They have settled at about 1060 nm in advance, with the complications ahead and BP5 ghost having good days in the future past (or past future ?) this will rather go down before it goes up again.

Well, with a bit of luck that could go up to 1100 before NZ, but I don't think that it will be that much.

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Two or three more records (almost getting to be expected this season):

Idec Sport exceeded longitude 146 ° 49 'East to mark the crossing of the southern tip of Tasmania , Tuesday, January 4, 2017 to 2 hours and 50 minutes TU .


Francis Joyon and his five teammates s'adjugent the WSSRC record for crossing the Indian Ocean, Cape Agulhas - Tasmania, 5 days, 21 hours and 9 minutes . The previous record was set in 2015 by the same Francis Joyon aboard the same Idec Sport in 7 days (time adjusted and ratified by the WSSRC).

The trimaran sets a new reference time between Ushant and Tasmania in 18 days, 18 hours and 31 minutes . Sport Idec account 1 day, 12 hours and 40 minutes ahead of the record 2011/2012 Banque Populaire V. The previous reference time over the same distance, was directed by Yann Guichard in 2015, in 20 days, 4 hours And 37 minutes.

Another way of reference time has been improved by Idec Sport:
- Cape Leeuwin - Tasmania: 1 day, 11 hours and 32 minutes (former holder Francis Joyon 1d 11h 41m 2015)

Chrome trans of http://www.fralo.info/jv01.html

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They have settled at about 1060 nm in advance, with the complications ahead and BP5 ghost having good days in the future past (or past future ?) this will rather go down before it goes up again.

Well, with a bit of luck that could go up to 1100 before NZ, but I don't think that it will be that much.

 

But in fact it looks like they will have a rather good connection between the low they are currently riding, and the next one that they should catch after NZ(around 36h from now), Even if in that case they will be on the back of it and not in front, but this next low coming down South East from NZ, the sea should be "acceptable".

After that they will probably have to "dive South" quite a bit to keep some good wind.

But Peyron really had a quite bad Pacific, they should get to the Horn with 3 if not 4 days ahead of current record.

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Last year Yann Guichard on Spindrift 2 made the Anti-méridien in 22j 7h 43m 2s.

The low looks to continue, and IDEC is about a day away (750nm). So, looks like another reference time will be re-written

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From the link above, the theoretical record (i.e. the sum of the partial records) would be 41d18h26m15s.Let's see if Idec's crew manages to beat it.

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Well, here's some things to say, while still in slack jawed awe. Most people did not believe the smaller boat would really be faster (me included, I "wanted to believe" like Fox Mulder but really didn't believe, like Agent Scully). But Joyon and crew have proven the skeptics wrong, they really are faster, and much faster, going lighter with a smaller mast and less crew. The sustained speeds indicate that they can ramp up to that level now that they have enough wind.

 

Putting a 40 knt speed limit on his crew, he has even throttled back now. It appears the next low is stationary for a while, and the transition to it continues to look like small bump, need to up North 4-5 degrees, hurting VMG slightly, but it appears they will have sustained wind. And they are starting to pass VG boats now.

 

Joyon said on a solo trip that stress is the harmony of a trimaran, or words to that effect, indicating that managing the stress on the boat is the central matter. I imagine that the boat has far less loading due to the lighter weight. That unlocks the speed without excessive danger of breaking. Will others try to follow this path, now proven? Will they have a choice if it is really faster?

 

Could Peyron modify BPV in the same manner? or Guichard modify Spindrift 2?

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@tama_manu

Spindrift 2 is the new name of BPV (slightly modified)

Otherwise I think the small crew might lead them to push the boat really hard, also they seem to have an ability to really go deep down wind, but I wouldn't say it is "proven" to be quicker, they have also been quite lucky with the conditions in the southern Ocean (not in the Atlantic and doldrums)

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Wonder if Joyon will try to drive through the middle of the low ahead rather than gybe across the top of it? Like he did solo near Cape Horn.

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That low seems to be going south, so I would say gybe.

Plus, they are fast, but not fast enough to go thru I think, sea state slow them down too.

 

VMG to Cape Horn has gone down now that they are pointing 68º, even if they keep above 30 kn.

 

 

Edit: Just got the transcription on fralo:

 

Francis Joyon : « Dans les 10 heures à venir, la dépression qui nous a bien aidés à traverser l’Indien, va s’arrêter là. L’idée est de monter un petit peu au Nord, de faire un empannage et de redescendre en passant par autre système qui est devant nous. On a renvoyé toute la grand-voile et on va surement faire un peu de gennaker dans la nuit aussi. Par contre quand nous serons dans la nouvelle dépression, ce sera à nouveau les petites voiles. Je pense que le Pacifique Sud est moins chargé en glace que ne l’était l’Atlantique. »

 

Rough translation:

"In 10 hours the low that help us cross the Indian will stop. The idea is to go a bit north, gybe, and go south again in the systen that is ahead. Main sail is up and probably will send up the gennaker during the night too. Once in the new low, that will be again small sails. I think that there are less ice in the South Pacific than in the Atlantique."

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If I read the weather forecast correctly on their tracker, in 3 days they will have to go REALLY deep down South (like 60 S) to keep some decent wind. Is it too dangerous because of icebergs? And on top of that, it would be around the most remote place on the planet...

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If I read the weather forecast correctly on their tracker, in 3 days they will have to go REALLY deep down South (like 60 S) to keep some decent wind. Is it too dangerous because of icebergs? And on top of that, it would be around the most remote place on the planet...

A quick google on iceberg concentration articles shows that between 160 and 130 W - where they will be in 3 days - icebergs tend to drift more regularly up to ~60 S. But if you buy and analyse satellite images, you know where (the larger ones) are.

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That was some ride along the low. Felt like it would last forever. Really quite sad it has ended.

 

Would it ever be feasible to take a low all the way round?

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Well, here's some things to say, while still in slack jawed awe. Most people did not believe the smaller boat would really be faster (me included, I "wanted to believe" like Fox Mulder but really didn't believe, like Agent Scully). But Joyon and crew have proven the skeptics wrong, they really are faster, and much faster, going lighter with a smaller mast and less crew. The sustained speeds indicate that they can ramp up to that level now that they have enough wind.

 

Putting a 40 knt speed limit on his crew, he has even throttled back now. It appears the next low is stationary for a while, and the transition to it continues to look like small bump, need to up North 4-5 degrees, hurting VMG slightly, but it appears they will have sustained wind. And they are starting to pass VG boats now.

 

Joyon said on a solo trip that stress is the harmony of a trimaran, or words to that effect, indicating that managing the stress on the boat is the central matter. I imagine that the boat has far less loading due to the lighter weight. That unlocks the speed without excessive danger of breaking. Will others try to follow this path, now proven? Will they have a choice if it is really faster?

 

Could Peyron modify BPV in the same manner? or Guichard modify Spindrift 2?

 

Spindrift has already had a big mod from when it was BPV. Shorter, lighter rig, and smaller, lighter sails.

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That was some ride along the low. Felt like it would last forever. Really quite sad it has ended.

 

Would it ever be feasible to take a low all the way round?

Normally they tend to go down south after a while, or get disrupted by another low coming from the north, or swallowed by a high (actually is the low that swallows the air in the hight).

 

This one has already survived one low coming from Australia, but the second one from NZ is much stronger. It's already amazing that it has lasted for half the turn ~ 10 days.

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Curiously, the times to the antimeridian were

LP - BP5 22j 11h 34m 12s in 2011-2012

YG- SD2 22j 7h 43m 2s in 2015-2016

FJ - IDECs 22j 9h 48m 38s in 2015-2016

 

less than 4 hours apart, yet in the end Loïck was about 2 days faster than Yann and Francis.

2 days ahead for Francis this time, with a good looking Pacific, really gives hope :)

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I would say at least 6 more hours before the gibe.

But that will depend on the actual wind direction rather than the forecast.

Maybe they will have some explanation besides "the routing sofware said so" .

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And gybed yet again for three. Three shall be the number...

 

Across the South Atlantic and Indian without a gybe; they must have been bored and wanted some practice, LOL.

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Bilan jour 12 - distance en 24h : 832.30 mn - moyenne : 34.68 nds - retard : 587.60 mn

Bilan jour 13 - distance en 24h : 872.80 mn - moyenne : 36.37 nds - retard : 369.20 mn

Bilan jour 14 - distance en 24h : 872.30 mn - moyenne : 36.35 nds - retard : 294 mn

Bilan jour 15 - distance en 24h : 869.40 mn - moyenne : 36.23 nds - retard : 117.40 mn

 

And it keeps going on !

It does keep going

 

Bilan jour 16 - distance en 24h : 856 mn - moyenne : 35.67 nds - reste : 13 455 mn - avance : 180.70 mn

Bilan jour 17 - distance en 24h : 803.90 mn - moyenne : 33.50 nds - reste : 12 809 mn - avance : 446.60 mn

Bilan jour 18 - distance en 24h : 716.70 mn - moyenne : 29.86 nds - reste : 12 146.40 mn - avance : 725.40 mn

Bilan jour 19 - distance en 24h : 816.90 mn - moyenne : 34.04 nds - reste : 11 433 mn - avance : 1 059.60 mn

Bilan jour 20 - distance en 24h : 801.50 mn - moyenne : 33.40 nds - reste : 10 793.30 mn - avance : 1 028.40 mn

 

That's 8 days over 800 miles, out of 9 days in the Southern Ocean. BPV had one day over 800 in its record run, not sure about the Spindrift 2 attempts (yes, the same boat but lighter)? IDEC Sport was obligated to sail that fast to stay with the low. The current transition only required 800 mile days rather than 870s, but it too will close out shortly. Is it just luck, or can we say IDEC is faster?

 

Nice "mouette" on the gybe(s) (five is straight out - unless they need to chase the low). Back to VMG sailing so "avance" will rise again. I hope they can miss all the ice without the gybe fest that was Coville's entry into the south on his record run.

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That adds up to 7441.7 nm in 9 days at an average of 826.85 nm per day ... so 34.45 knots.

That gives a new meaning to the Speed Week :)

 

Spindrift 2 should be able to keep the pace given the right conditions, but in the same conditions ?

 

Edit: New gibe !

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Spindrift 2 is likely faster in the same conditions. That's been proven in the transat with the boats in their original conditions; it's hard to make up for waterline! I suspect the smaller rig deal came from the need for all crew on deck to reef the main on the original BPV, IIRC. That's a high level of exhaustion and plays directly into Joyons decision to go with team used to handling maneuvers entirely solo.

 

My fingers remain crossed that IDEC and crew nail this one, they've had an incredible run so far!! Hopefully the climb back up the Atlantic pans out!!

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I guess the question is really whether the gains in the strong breeze of the southern ocean are enough to cover the losses he will have going up the Atlantic, where his smaller rig will be a disadvantage.

 

Let's hope so.

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That adds up to 7441.7 nm in 9 days at an average of 826.85 nm per day ... so 34.45 knots.

That gives a new meaning to the Speed Week :)

 

 

LOL, good one.

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Spindrift 2 is likely faster in the same conditions. That's been proven in the transat with the boats in their original conditions; it's hard to make up for waterline! I suspect the smaller rig deal came from the need for all crew on deck to reef the main on the original BPV, IIRC. That's a high level of exhaustion and plays directly into Joyons decision to go with team used to handling maneuvers entirely solo.

 

My fingers remain crossed that IDEC and crew nail this one, they've had an incredible run so far!! Hopefully the climb back up the Atlantic pans out!!

 

Speed: A question remains though, given the different sea state in the North Atlantic crossing. Just a guess.

(I fail to imagine how it feels to be speeding on one float in that kind of conditions, and how more frightening it is on a bigger beast.)

Also Joyon said that he set a 40 knots speeding limit, which may mean that BPV/Spindrift might have not been able to use their waterline advantage.

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Spindrift 2 is likely faster in the same conditions. That's been proven in the transat with the boats in their original conditions; it's hard to make up for waterline! I suspect the smaller rig deal came from the need for all crew on deck to reef the main on the original BPV, IIRC. That's a high level of exhaustion and plays directly into Joyons decision to go with team used to handling maneuvers entirely solo.

 

My fingers remain crossed that IDEC and crew nail this one, they've had an incredible run so far!! Hopefully the climb back up the Atlantic pans out!!

 

Yup. About the smaller rig, you may appreciate Laurent's post from last year #19

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The Pacific routing does not seem so easy to me as some here suggest. Its not my forte so defer to others but thinking things look difficult ahead.

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In the latest article on the IDECSport-Sailing website, the English translation does not carry all the nuances of the French version.

For instance, Francis Joyon is saying that after so many jibes, they were able to catch the weather system in front of them "by a hair"....

But now, they seem to my untrained eye firmly into that system; and I guess they will not stop at 57°S but potentially go much further South, icebergs permitting...

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Joyon day 20:

On voit que le Cap Horn est assez accessible. Il n’y a pas d’énorme obstacle météo à part un anticyclone qui bouche un peu le passage à mi-Pacifique. Il laisserait un petit passage en descendant assez Sud. Le Pacifique resterait relativement rapide. Correct ! Très correct !

 

We see that Cape Horn is quite accessible, there's no enormous meteo obstacle besides a high that blocks a little the passing half Pacifique. It will allow a small pass quite south. The pacifique will be quite fast. Correct ! Very correrct !

 

 

Joyon day 22:

 

Jusqu’au Cap Horn on aura plusieurs systèmes à traverser. Une dépression qu’on attrape par le Nord puis on visera son centre de façon à pouvoir ressortir dans des vents de Nord-Ouest. Après on aura un anticyclone qui barrera la route et nous obligera à descendre très très Sud dans les glaces. Il faudra réussir à se faufiler entre les glaces et cet anticyclone en descendant le plus Sud possible.

 

Till Cape Horn we'll have several systems to go thru. A low that we catch from the Nord, then we'll target it's center so we can get out to NW winds. After will have a high that will make us go very very south, into the ices. We'll need to slip between the ices and the high going as south as possible.

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The Pacific routing does not seem so easy to me as some here suggest. Its not my forte so defer to others but thinking things look difficult ahead.

If there is ice very difficult indeed, if not it looks fine near great circle route. 9 January around 63 South 115 West as a southern most point, but could go further south 2 degrees if no ice problems. Not as fast as Indian ocean as less wind along the route now and then, but still quite fast and much shorter than staying in the same latitudes like in the Indian ocean. Thus high VMC towards Cap Horn anyway. 3000 miles in 4 days 10 hours averaging 680 miles a day seems possible. 5 days ahead at Horn with such performance. Would expect my guesswork to be 1 day off at most, if the weather will be as now predicted.

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Now they will most probably have to go really South, but when you consider the shortest route ::

 

joyonhorn-e1483741315835.jpeg

 

It's really the way to go !

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So . . . even the "oldest record" is being challenged:

In the series "Everything is possible": the oldest record in the world

 

The most assiduous and attentive readers of this site will certainly have noted that Bruno Peyron keeps in his bag, since 2005, the oldest record WSSRC, on a tour of the world. This is the record of crossing the Pacific Ocean to the southern tip of Tasmania to Cape Horn, established in 8 days, 18 hours and 8 minutes , aboard the catamaran Orange II.
Do you see where I am coming from? Me too ...
According to the rule set by the WSSRC to break the record of one minute, Idec Sport should cross the longitude of Cape Horn at the latest on Thursday 12 January 2017 8:57 p.m. .
If Francis Joyon and his teammates realized this feat, I dare not even tell you what advance they would have on Banque Populaire V! To prepare yourself psychologically for the shock, then count on a piece of paper.

Chrome trans of article above Day 23 http://www.fralo.info/jv01.html in reference to http://www.fralo.info/jv07.html

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So . . . even the "oldest record" is being challenged:

In the series "Everything is possible": the oldest record in the world

 

The most assiduous and attentive readers of this site will certainly have noted that Bruno Peyron keeps in his bag, since 2005, the oldest record WSSRC, on a tour of the world. This is the record of crossing the Pacific Ocean to the southern tip of Tasmania to Cape Horn, established in 8 days, 18 hours and 8 minutes , aboard the catamaran Orange II.
Do you see where I am coming from? Me too ...
According to the rule set by the WSSRC to break the record of one minute, Idec Sport should cross the longitude of Cape Horn at the latest on Thursday 12 January 2017 8:57 p.m. .
If Francis Joyon and his teammates realized this feat, I dare not even tell you what advance they would have on Banque Populaire V! To prepare yourself psychologically for the shock, then count on a piece of paper.

Chrome trans of article above Day 23 http://www.fralo.info/jv01.html in reference to http://www.fralo.info/jv07.html

 

One thing this website does not point out is that Thomas Coville has recently established the Singlehanded Pacific record with 8d 18h 28' - only 10' short of the outright record.

 

Achieving this kind of time looks extremely important for this attempt sucess.

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[snip]

Chrome trans of article above Day 23 http://www.fralo.info/jv01.html in reference to http://www.fralo.info/jv07.html

 

One thing this website does not point out is that Thomas Coville has recently established the Singlehanded Pacific record with 8d 18h 28' - only 10' short of the outright record.

 

Achieving this kind of time looks extremely important for this attempt success.

 

Ah--good point. I miss Volodia's tracker, where we might have seen that more easily :)

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Will they be able to link in to the breeze just ahead of them?

 

If so they will be looking sweet.

 

Yes they should, but they then might have to Gybe reallt a lot, Joyon talking about 50 gybes according to some routing :

 

http://www.idecsport-sailing.com/pres-de-1-200-milles-davance-par-59-sud/

 

https://soundcloud.com/idecsport/interview-de-francis-joyon-le-08012017-a-15h00

 

Plenty of gybes to finish up this almost fully straight south Ocean route would really make the rout a work of art

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OK so they are not going the really deep south balls to wall route. More in line w what I thought I saw and more conservative. Think they might just miss the first elevator at the horn but they can afford a slow day (or more) with this lead.

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The big difference for Loïck Peyron's record was the part between Cape Horn and the Equator, he was 2 & 1/2 days faster than Previous record by Frank Cammas and neither Yann Guichard nor Joyon could get it under 9 days during the 2015 attempt.

CH - Equator
LP BP5 7j 04 h27m
FC Ga3 9j 16 h35m + 2j 12h 8m
YG Sd2 9j 09 h24m + 2j 4h 53m
FJ Is1 9j 13 h06m + 2j 8h 38m
The difference in the overall time Ouessant-Ouessant is only a few hours apart from the difference in C.Horn-Equator segment.
This time, though, looks like Joyon will have a 4tish days margin in his favor, so it should be enough.

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ok betting people. Nothing really to talk about with Vendee for the next 5 hours. Here in Jules Verne land, can Idec get past Banque Pop's Day 29 progress point before it lays its next tracker egg in 9 hours?

 

I'm going with yes, which would put them 4 full days ahead of the record.

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ok betting people. Nothing really to talk about with Vendee for the next 5 hours. Here in Jules Verne land, can Idec get past Banque Pop's Day 29 progress point before it lays its next tracker egg in 9 hours?

 

I'm going with yes, which would put them 4 full days ahead of the record.

 

Hmm. 9 hrs to do 130+ miles? Should be doable. Yes.

post-63767-0-98469100-1484004738_thumb.png

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I think so too, not so sure if by the time they turn left after the Horn they will still be 4 full days ahead.

They need to keep pretty high speeds to avoid the calm around CH on Wednesday night

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i wonder how long it takes to get desensitised to the feel and sight of trucking along for hours at speeds most of us have never even glimpsed on a sailing boat.

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OK so they are not going the really deep south balls to wall route. More in line w what I thought I saw and more conservative. Think they might just miss the first elevator at the horn but they can afford a slow day (or more) with this lead.

I think they will be slightly more than 4 days ahead at the Cap Horn, but less than 2 days by the equator.

 

If the north Atlantic does not improve, i don't think they make it in time to make the record, but there is plenty of chance for a much better north Atlantic weather than it is now.

Thus they'll still have a good chance to succeed making new circumnavigation record, but most likely not with several days advantage.

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Fun with numbers. fralo tweeted an interesting table: a sub-40 day rtw *might* be possible:

C1uFos1W8AAu94a.jpg

https://twitter.com/Fralo_info/status/818394704689725440

I think sub 40 days rtw is possible and not just based on those numbers for statistics.

The fact IdecSport can be so successful with such a short rig indicates that a similarly short rigid wing in a light catamaran platform could be used successfully for rtw record with same number of crew and even with slightly higher righting moment. Inability to reef is obviously not such a big problem with such small rig with low center of gravity than it would be with taller rig, especially considering capabilities of modern weather routing and forecasting.

 

The lightest weight for a given RM in a platform having equal performance in both tacks, is achieved with a narrow catamaran resulting substantially lighter beams, and water ballast used in an external tank located substantially outboard from the windward hull of the catamaran. Even as far as one boat length from the leeward hull and the weight supported with an extra shroud from the mast, thus providing very large staying base for the mast, and thus allowing a very light mast for a given RM and rig height combination. Lack of headstay tension or mainsail leach tension due to being a wingrig helps a lot too for keeping it very light.

In order to keep the tank laterally in place it needs only a very light deck spreader, allowed to be freely pivoted at both ends, and thus not under any bending loads, just same amount of compression as the weight of the ballast. This means the deck spreader could weight as little as the same length mast, for example one used in a Seacart 30, because unlike those used in IMOCA 60, it is only hold down by ballast weight, not any rigging causing a lot of compression. Rigging only holds it up and adjust its position longitudinally, similarly of stabilizing outriggers used in fishing trawlers. There is also no need for it to extend all the way to the mast, just at the deck edge of the catamaran windward hull in the most suitable longitudinal position, aft from center of weight of the boat so that while adjusting the longitudinal position of the ballast tank for most suitable bow up/down trim depending on apparent wind angle and speed, it is located as far laterally as possible for a given spreader length.

Such a 100+ ft catamaran using 2.5 ... 3 tons of water ballast, could weight between 10 ... 12 tons with same RM as IdecSport while having less windage due to smaller beams, no windward ama and more efficient rigid wing. I can't see any reason why it would not be much faster with the same structural safety margin as used in ocean racing maxi trimarans of today.

Ballast tanks for that size could have a hull like shape in case it occasionally hits a wave top, but be much shorter than the 100+ ft cat hull (30 ft at most), and thus be much lighter.

 

I wonder how many years it takes before someone actually builds one like that, or at least uses a rigid wing rig in ocean racing?

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Neat idea, but too much risk with a rigid wing sail in an ocean race I think. I see a semi-rigid wing sail as more practical, but the sail must be reef-able and all canvas eliminated on demand! One watch of the top gear AC45 episode should give you plenty of ideas on why ocean racing tris have more than 2 reefs in their mains, even with the smaller rigs, and why wing sail tech just isn't there yet for offshore use, though I'm hopeful creative minds such as yourself are working on it, because regular laps in sub 40 days would be impressive!

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Fun with numbers. fralo tweeted an interesting table: a sub-40 day rtw *might* be possible:

C1uFos1W8AAu94a.jpg

https://twitter.com/Fralo_info/status/818394704689725440

I think sub 40 days rtw is possible and not just based on those numbers for statistics.

The fact IdecSport can be so successful with such a short rig indicates that a similarly short rigid wing in a light catamaran platform could be used successfully for rtw record with same number of crew and even with slightly higher righting moment. Inability to reef is obviously not such a big problem with such small rig with low center of gravity than it would be with taller rig, especially considering capabilities of modern weather routing and forecasting.

 

The lightest weight for a given RM in a platform having equal performance in both tacks, is achieved with a narrow catamaran resulting substantially lighter beams, and water ballast used in an external tank located substantially outboard from the windward hull of the catamaran. Even as far as one boat length from the leeward hull and the weight supported with an extra shroud from the mast, thus providing very large staying base for the mast, and thus allowing a very light mast for a given RM and rig height combination. Lack of headstay tension or mainsail leach tension due to being a wingrig helps a lot too for keeping it very light.

In order to keep the tank laterally in place it needs only a very light deck spreader, allowed to be freely pivoted at both ends, and thus not under any bending loads, just same amount of compression as the weight of the ballast. This means the deck spreader could weight as little as the same length mast, for example one used in a Seacart 30, because unlike those used in IMOCA 60, it is only hold down by ballast weight, not any rigging causing a lot of compression. Rigging only holds it up and adjust its position longitudinally, similarly of stabilizing outriggers used in fishing trawlers. There is also no need for it to extend all the way to the mast, just at the deck edge of the catamaran windward hull in the most suitable longitudinal position, aft from center of weight of the boat so that while adjusting the longitudinal position of the ballast tank for most suitable bow up/down trim depending on apparent wind angle and speed, it is located as far laterally as possible for a given spreader length.

Such a 100+ ft catamaran using 2.5 ... 3 tons of water ballast, could weight between 10 ... 12 tons with same RM as IdecSport while having less windage due to smaller beams, no windward ama and more efficient rigid wing. I can't see any reason why it would not be much faster with the same structural safety margin as used in ocean racing maxi trimarans of today.

Ballast tanks for that size could have a hull like shape in case it occasionally hits a wave top, but be much shorter than the 100+ ft cat hull (30 ft at most), and thus be much lighter.

 

I wonder how many years it takes before someone actually builds one like that, or at least uses a rigid wing rig in ocean racing?

 

I think I can follow your idea, and imagine that in flat water such a plan might work. Can't imagine it working in rough seas with the leverage of that ballast generating all kinds of forces as the boat accelerates and stops dead. However, others would know best.

 

As for wings, I expect someone will try the sailboard style where forces lift as much as drive ahead. Where RM becomes "lifting moment".

 

Anyway, back on topic, maybe IDEC will have a chance at breaking 40 days: looks like they might hang onto enough wind around the Horn and catch the elevator up the Atlantic.

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Neat idea, but too much risk with a rigid wing sail in an ocean race I think. I see a semi-rigid wing sail as more practical, but the sail must be reef-able and all canvas eliminated on demand! One watch of the top gear AC45 episode should give you plenty of ideas on why ocean racing tris have more than 2 reefs in their mains, even with the smaller rigs, and why wing sail tech just isn't there yet for offshore use, though I'm hopeful creative minds such as yourself are working on it, because regular laps in sub 40 days would be impressive!

With at tall rig like AC 45 or AC 72 the idea of a wing rig in ocean racing would obviously not work, but if rig height is just the same as length of the hulls (Idec is very close to that) I think it would already be different. You simply replace reefing with filling up more ballast water gaining more stability, reduce flap angle and/or angle of attack of the wing, and keep the deck spreader at a suitable longitudinal position by pivoting it around the inner end, so that the ballast prevents pitchpoling just as well as capsizing sideways or diagonally, that is align the righting effect with the aerodynamic force of the wing at all times.

 

In places like doldrums where sudden squalls are expected in unknown direction (thunderstorms?), you can even extend ballast tanks in both sides simultaneously and if need be let them drag in the water. The lee side will then cause no load on the rig, as buoyancy of the tank will cancel out it's weight. You slow down momentarily if/when doing that, but it can be done safely in structural point of view.

 

 

 

 

 

 

I think I can follow your idea, and imagine that in flat water such a plan might work. Can't imagine it working in rough seas with the leverage of that ballast generating all kinds of forces as the boat accelerates and stops dead. However, others would know best.

As for wings, I expect someone will try the sailboard style where forces lift as much as drive ahead. Where RM becomes "lifting moment".

 

Anyway, back on topic, maybe IDEC will have a chance at breaking 40 days: looks like they might hang onto enough wind around the Horn and catch the elevator up the Atlantic.

 

Yes, ballast extended to the side will need forces to accelerate it in a seaway, but if you compare it to ballast bulb of a canting keel monohull there is a major difference, it can be easily supported with adjustable rigging ropes located above waterline providing the needed support in all directions while in a monohull it must be supported with a very thin keel strut under heavy bending and twisting loads. The stiffness of those ropes can be freely selected to lead into minimum loads. And the angle of the rigging for that deck spreader can be 45 degrees for upwards support to the mast and above 75 degrees for the rest, while in masts rigging angle is typically less than 15 degs for monohulls.

 

I'm not sure I understood that sailboard style comment correctly. If you meant canting rig like in sailrocket2, it requires the mast step to be located well into leeward, otherwise any upwards lift reduces RM too much. In most current platforms canting is done to keep mast mostly upright regardless of heeling angle, or slightly more to shift center of gravity of mast & sails & rigging windward to increase RM, but with very little upwards lift.

 

Can you pinpoint any future waypoints with possible time stamps for Idec up the atlantic indicating any chance of breaking 40 days.

I fail to find any possible routes allowing that and find your claim/suggestion interesting.

I think I can follow your idea, and imagine that in flat water such a plan might work. Can't imagine it working in rough seas with the leverage of that ballast generating all kinds of forces as the boat accelerates and stops dead. However, others would know best.

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Back to the race: Looks like 26 and 1/2 days is plausible at CH. 900 miles to go till the black rock. Then lot of time to spare up the Atlantic tough a sub 40 days mark won't be realistic with conditions ahead at the Atlantic. We will see.

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..

 

I wonder how many years it takes before someone actually builds one like that, or at least uses a rigid wing rig in ocean racing?

 

 

You surely need a crew with big balls in the southern ocean with a large wingmast in case things turn bad.

http://www.ultimboat.com/royale-ii (all I could find about this cat)

 

But you can be sure, someone will try :wacko:

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The lightest weight for a given RM in a platform having equal performance in both tacks, is achieved with a narrow catamaran resulting substantially lighter beams, and water ballast used in an external tank located substantially outboard from the windward hull of the catamaran.

 

 

Close, but not quite correct. The lightest weight for a given rm is a harryproa. An example is the 20m/66' fast cruiser currently being built in Norway, which is on track to weigh 6 tons, ready to cruise. http://harryproa.com/?p=726#more-726 It has glass/foam hulls and is about twice the surface area it would be if it was a race boat.

 

Adding water ballast has merit, but I think it would be better in the ww hull rather than adding the complexity and windage of a third "hull", beams and rigging.

 

 

Canting the rig to windward and telescoping it also has merit (we are fitting both to a 40'ter at the moment), but the crew has to be very alert as flying the hull with a windward canted rig increases the capsize force.

 

rob

www.harryproa.com

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Back to the race: Looks like 26 and 1/2 days is plausible at CH. 900 miles to go till the black rock. Then lot of time to spare up the Atlantic tough a sub 40 days mark won't be realistic with conditions ahead at the Atlantic. We will see.

The forecast for the south Atlantic in 3~4 days doesn't look good at all :(

They will need these 4 days cushion that the southern ocean has provided.

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The lightest weight for a given RM in a platform having equal performance in both tacks, is achieved with a narrow catamaran resulting substantially lighter beams, and water ballast used in an external tank located substantially outboard from the windward hull of the catamaran.

 

 

Close, but not quite correct. The lightest weight for a given rm is a harryproa. An example is the 20m/66' fast cruiser currently being built in Norway, which is on track to weigh 6 tons, ready to cruise. http://harryproa.com/?p=726#more-726 It has glass/foam hulls and is about twice the surface area it would be if it was a race boat.

 

Adding water ballast has merit, but I think it would be better in the ww hull rather than adding the complexity and windage of a third "hull", beams and rigging.

 

 

Canting the rig to windward and telescoping it also has merit (we are fitting both to a 40'ter at the moment), but the crew has to be very alert as flying the hull with a windward canted rig increases the capsize force.

 

rob

www.harryproa.com

 

I thought proas shunt, not tack, and if they do tack they don't have the same performance in both tacks, therefore I already ruled them out in my statement you just quoted.

Your harryproas seem to have beams carrying RM by bending moment, thus substantially heavier than if stayed mast were used, but that is only valid if built so that beams fail if tacked, since the mast located in a leeward hull can't be supported by staying from all directions.

Water ballast is more effective the more outward it is located, as far as the least weight for a given RM (in all directions) is concerned. Double RM for the same weight easily outperforms added windage of the extras. Complexity of build & design & engineering is irrelevant if the best performance is the target, instead of practicality or cost.

 

For example 12 m beam between centerlines and 14 m overall beam of the 30 m long cat, and 3 ton ballast located 30 m from the leeward hull centerline when 17 m long deck spreader is perpendicular. Having the ballast in windward hull would reduce RM more than 50% or if heavier ballast were used mast & beams would be substantially heaver for the same RM, due to narrower staying base and thus greater mast compression loads. Wider cat with same ballast and RM would also be heavier due to increased beam weight.

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..

 

I wonder how many years it takes before someone actually builds one like that, or at least uses a rigid wing rig in ocean racing?

 

 

You surely need a crew with big balls in the southern ocean with a large wingmast in case things turn bad.

http://www.ultimboat.com/royale-ii (all I could find about this cat)

 

But you can be sure, someone will try :wacko:

 

That design is a lot different than what I suggested. 72+ % less RM with only 1 m shorter rig, and 25+ % shorter hulls. Royale is clearly optimised for much lower windspeeds than IDEC SPORT and can't survive without reefing or added RM in rtw route.

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Well I was wrong, again. 1900 m leading in front of BP will happen today. It will 2000 m by tomorrow. More than enough to accomplish the ultimate goal. I think only the Dona Bertarelly mistress and her crew can brake down this amazing time... if weather cooperates.

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Neat idea, but too much risk with a rigid wing sail in an ocean race I think. I see a semi-rigid wing sail as more practical, but the sail must be reef-able and all canvas eliminated on demand! One watch of the top gear AC45 episode should give you plenty of ideas on why ocean racing tris have more than 2 reefs in their mains, even with the smaller rigs, and why wing sail tech just isn't there yet for offshore use, though I'm hopeful creative minds such as yourself are working on it, because regular laps in sub 40 days would be impressive!

 

 

On the new mini ARKEMA , Lalou Roucayrol try a soft wingsail reef-able and foils .

 

 

a78d78525584649.jpg 872a98525584660.jpg

 

The wing is from Romaric Neyhousser ( team Roucayrol designer ) and after covered by Incidences Voiles

 

May be somebody can translate this

 

 

Une aile souple comme gréement

Le Mini 6.50 Arkema 3 est équipé d’une voile en tissu épais à deux éléments, à l'image des ailes des Class C ou des voiliers de la Coupe America, mais non rigide. Contrairement aux voiliers qui naviguent en baie, il fallait pouvoir réduire la toile sur le Mini 6.50 (prendre des ris et affaler complètement la voile). Le système devant être fiable et gérable par un skipper en solitaire dans les conditions océaniques.

 

Romaric Neyhousser : "Nous avons conçu une aile à deux éléments : un élément avant, autour du mât, et un élément arrière. Le deuxième est articulé sur le premier avec un axe de rotation déporté en avant de la chute pour créer un gap, une fente, entre les deux éléments. Toute la difficulté a résidé dans le fait de pouvoir tendre le tissu. Nous avons mis en place un système avec des profils qui permettent d’obtenir cette "allure" d’aile épaisse. Des formes en carbone, qui coulissent le long du mât, donnent un intrados et un extrados à l’aile."

César Dohy, maître voilier chez Incidence Sails, explique : "L’entoilage de l’aile s’est fait à partir de matériaux souples pour que le marin puisse faire varier la hauteur de la voile. Nous avons utilisé un tissu conventionnel, car nous étions bloqués par la jauge qui n’autorise que le polyester".

L’ensemble est donc articulé autour du mât, qui n’est pas apparent une fois la voile hissée. Encastré entre le fond de coque et le pont du bateau, le mât est partiellement autoporté sans haubans pour le maintenir. Seuls un étai pour porter la voile d’avant et des bastaques servent à le stabiliser.

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Fun with numbers. fralo tweeted an interesting table: a sub-40 day rtw *might* be possible:

C1uFos1W8AAu94a.jpg

https://twitter.com/Fralo_info/status/818394704689725440

I think sub 40 days rtw is possible and not just based on those numbers for statistics.

The fact IdecSport can be so successful with such a short rig indicates that a similarly short rigid wing in a light catamaran platform could be used successfully for rtw record with same number of crew and even with slightly higher righting moment. Inability to reef is obviously not such a big problem with such small rig with low center of gravity than it would be with taller rig, especially considering capabilities of modern weather routing and forecasting.

 

The lightest weight for a given RM in a platform having equal performance in both tacks, is achieved with a narrow catamaran resulting substantially lighter beams, and water ballast used in an external tank located substantially outboard from the windward hull of the catamaran. Even as far as one boat length from the leeward hull and the weight supported with an extra shroud from the mast, thus providing very large staying base for the mast, and thus allowing a very light mast for a given RM and rig height combination. Lack of headstay tension or mainsail leach tension due to being a wingrig helps a lot too for keeping it very light.

In order to keep the tank laterally in place it needs only a very light deck spreader, allowed to be freely pivoted at both ends, and thus not under any bending loads, just same amount of compression as the weight of the ballast. This means the deck spreader could weight as little as the same length mast, for example one used in a Seacart 30, because unlike those used in IMOCA 60, it is only hold down by ballast weight, not any rigging causing a lot of compression. Rigging only holds it up and adjust its position longitudinally, similarly of stabilizing outriggers used in fishing trawlers. There is also no need for it to extend all the way to the mast, just at the deck edge of the catamaran windward hull in the most suitable longitudinal position, aft from center of weight of the boat so that while adjusting the longitudinal position of the ballast tank for most suitable bow up/down trim depending on apparent wind angle and speed, it is located as far laterally as possible for a given spreader length.

Such a 100+ ft catamaran using 2.5 ... 3 tons of water ballast, could weight between 10 ... 12 tons with same RM as IdecSport while having less windage due to smaller beams, no windward ama and more efficient rigid wing. I can't see any reason why it would not be much faster with the same structural safety margin as used in ocean racing maxi trimarans of today.

Ballast tanks for that size could have a hull like shape in case it occasionally hits a wave top, but be much shorter than the 100+ ft cat hull (30 ft at most), and thus be much lighter.

 

I wonder how many years it takes before someone actually builds one like that, or at least uses a rigid wing rig in ocean racing?

So you want to do a quatrimaran?

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Who cares, maybe discuss with Doug?

 

Let's go back to the live programming. These guys are gonna destroy this record !

 

26d 5h is my refined horn prediction :)

 

Nice. Hope you're right and the calms are avoided--they'd add another day otherwise. Joyon:

Double or quits

He is hesitating for the moment between north and south, as he admits, “We’re putting off this decision for as long as we can. In around twelve hours, we will be able to decide whether or not to take the direct route.” He is not hiding the fact that he would like to take the shortest route, allowing the men to greet the Horn sooner, some time tomorrow evening, after building up an incredible lead threatening the round the world record (45d 13h 45mn 53 sec) as they begin the final third of their circumnavigation.

But Francis Joyon still has his doubts and is keeping a close watch on any changes. He is not willing to gamble on getting stuck in a shallow low. Facing the uncertainty about the weather, the routing programmes cannot agree. They go from one extreme to the other with the most pessimistic seeing him round the Horn on Thursday afternoon, one day and five hours after the most optimistic routing.

http://www.idecsport-sailing.com/straight-on-and-out-of-the-southern-ocean/?lang=en

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Who cares, maybe discuss with Doug?

 

Let's go back to the live programming. These guys are gonna destroy this record !

 

26d 5h is my refined horn prediction :)

 

Nice. Hope you're right and the calms are avoided--they'd add another day otherwise. Joyon:

Double or quits

He is hesitating for the moment between north and south, as he admits, “We’re putting off this decision for as long as we can. In around twelve hours, we will be able to decide whether or not to take the direct route.” He is not hiding the fact that he would like to take the shortest route, allowing the men to greet the Horn sooner, some time tomorrow evening, after building up an incredible lead threatening the round the world record (45d 13h 45mn 53 sec) as they begin the final third of their circumnavigation.

But Francis Joyon still has his doubts and is keeping a close watch on any changes. He is not willing to gamble on getting stuck in a shallow low. Facing the uncertainty about the weather, the routing programmes cannot agree. They go from one extreme to the other with the most pessimistic seeing him round the Horn on Thursday afternoon, one day and five hours after the most optimistic routing.

http://www.idecsport-sailing.com/straight-on-and-out-of-the-southern-ocean/?lang=en

 

 

Eric Bellion is about 300nm from Cape Horn, Conrad is about 385nm, and IDEC has about 650 to go sailing about twice as fast. They should really coordinate their routes to film each other at the Horn. :)

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Eric Bellion is about 300nm from Cape Horn, Conrad is about 385nm, and IDEC has about 650 to go sailing about twice as fast. They should really coordinate their routes to film each other at the Horn. :)

 

That would be nice.

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Excuse the horrid french, but here's what I've got. Only a few missing words. Maybe Laurent will chime in...

 

An installed soft wing

The Mini650 Arkema 3 is equipped with a soft sail with two elements, like the mainsails (wings) on sailboats like the C Class or America's Cup, but non-rigid. Unlike daysailers, one must be able to reduce the sail on the Mini (tuck reefs or take down completely). The system must be efficient and reliable for ocean-going solo skippers.

 

Romaric Neyhousser: "We've thought up a wing of two elements, one in front, around the mast, and one in behind. The latter articulates on the front, with a rotation axis placed in front of the leech to create a gap, a "slot", between the two elements. All the difficulty resides in being able to stretch the fabric (in between the battens). We have set up a system with profiles (battens) to obtain this wing shape. These carbon forms, which slide up and down the mast, give a intrados and extrados to the wing."

Cesar Dohy, head sailmaker at Incidence Sails, explains: "The interlining (skin) of the wing is made in pieces of soft fabric so the skipper can change the height of the sail. We used a conventional fabric, as we were limited by the letter of the rule (Classe Mini) which prohibits anything besides polyester".

The entire thing rotates around a mast, which is not visible once the sail is fully hoisted. Supported between the deck and bottom of the hull, the mast is partially unsupported, using a forestay only for supporting headsails, and runners aft to stabilise.

 

FWIW, Google Translate did a very good job with copy/paste, only missing a few words.

 

HW

 

 



Neat idea, but too much risk with a rigid wing sail in an ocean race I think. I see a semi-rigid wing sail as more practical, but the sail must be reef-able and all canvas eliminated on demand! One watch of the top gear AC45 episode should give you plenty of ideas on why ocean racing tris have more than 2 reefs in their mains, even with the smaller rigs, and why wing sail tech just isn't there yet for offshore use, though I'm hopeful creative minds such as yourself are working on it, because regular laps in sub 40 days would be impressive!

 

 

On the new mini ARKEMA , Lalou Roucayrol try a soft wingsail reef-able and foils .

 

 

a78d78525584649.jpg 872a98525584660.jpg

 

The wing is from Romaric Neyhousser ( team Roucayrol designer ) and after covered by Incidences Voiles

 

May be somebody can translate this

 

 

Une aile souple comme gréement

Le Mini 6.50 Arkema 3 est équipé d’une voile en tissu épais à deux éléments, à l'image des ailes des Class C ou des voiliers de la Coupe America, mais non rigide. Contrairement aux voiliers qui naviguent en baie, il fallait pouvoir réduire la toile sur le Mini 6.50 (prendre des ris et affaler complètement la voile). Le système devant être fiable et gérable par un skipper en solitaire dans les conditions océaniques.

 

Romaric Neyhousser : "Nous avons conçu une aile à deux éléments : un élément avant, autour du mât, et un élément arrière. Le deuxième est articulé sur le premier avec un axe de rotation déporté en avant de la chute pour créer un gap, une fente, entre les deux éléments. Toute la difficulté a résidé dans le fait de pouvoir tendre le tissu. Nous avons mis en place un système avec des profils qui permettent d’obtenir cette "allure" d’aile épaisse. Des formes en carbone, qui coulissent le long du mât, donnent un intrados et un extrados à l’aile."

César Dohy, maître voilier chez Incidence Sails, explique : "L’entoilage de l’aile s’est fait à partir de matériaux souples pour que le marin puisse faire varier la hauteur de la voile. Nous avons utilisé un tissu conventionnel, car nous étions bloqués par la jauge qui n’autorise que le polyester".

L’ensemble est donc articulé autour du mât, qui n’est pas apparent une fois la voile hissée. Encastré entre le fond de coque et le pont du bateau, le mât est partiellement autoporté sans haubans pour le maintenir. Seuls un étai pour porter la voile d’avant et des bastaques servent à le stabiliser.

 

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The lightest weight for a given RM in a platform having equal performance in both tacks, is achieved with a narrow catamaran resulting substantially lighter beams, and water ballast used in an external tank located substantially outboard from the windward hull of the catamaran.

 

 

Close, but not quite correct. The lightest weight for a given rm is a harryproa. An example is the 20m/66' fast cruiser currently being built in Norway, which is on track to weigh 6 tons, ready to cruise. http://harryproa.com/?p=726#more-726 It has glass/foam hulls and is about twice the surface area it would be if it was a race boat.

 

Adding water ballast has merit, but I think it would be better in the ww hull rather than adding the complexity and windage of a third "hull", beams and rigging.

 

 

Canting the rig to windward and telescoping it also has merit (we are fitting both to a 40'ter at the moment), but the crew has to be very alert as flying the hull with a windward canted rig increases the capsize force.

 

rob

www.harryproa.com

 

I thought proas shunt, not tack, and if they do tack they don't have the same performance in both tacks, therefore I already ruled them out in my statement you just quoted.

Your harryproas seem to have beams carrying RM by bending moment, thus substantially heavier than if stayed mast were used, but that is only valid if built so that beams fail if tacked, since the mast located in a leeward hull can't be supported by staying from all directions.

Water ballast is more effective the more outward it is located, as far as the least weight for a given RM (in all directions) is concerned. Double RM for the same weight easily outperforms added windage of the extras. Complexity of build & design & engineering is irrelevant if the best performance is the target, instead of practicality or cost.

 

For example 12 m beam between centerlines and 14 m overall beam of the 30 m long cat, and 3 ton ballast located 30 m from the leeward hull centerline when 17 m long deck spreader is perpendicular. Having the ballast in windward hull would reduce RM more than 50% or if heavier ballast were used mast & beams would be substantially heaver for the same RM, due to narrower staying base and thus greater mast compression loads. Wider cat with same ballast and RM would also be heavier due to increased beam weight.

 

 

Harryproas perform the same on port and starboard, the only difference is how they change (shunting instead of gybing or tacking and no need to swap the water ballast).

 

A 3 ton pod of water hanging 17m off the windward hull of your cat would be a slow pain to tack or gybe and a disaster if this happened accidentally. A 1m diameter pod would be >4m long and weigh ~50 kgs. You will not reliably support this with a simple deck spreader and a couple of strings. Nor will you easily unship it, carry across the boat and reset it in conditions which justify it's use.

 

The beam weight is a small part of the total weight on a proa and all of it is contributing to rm. If the boat was going to regularly exceed 30 knots, it would pay to put flaps on it (a single beam is all that is required) for +/- aero lift. Much better than lugging around 3.5 tonnes of hull, water and rigging 17m off the side of the boat.

 

Suggest you build a model and try it on a pond to see the complexities you are facing.

 

You are correct about the uselessness of rigging attaching the beam to the mast.

 

Sorry for the thread drift.

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But a key issue with proa is also the rudders an daggerboard, having to work both ways or lifted (lifted for rudders clearly)

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But a key issue with proa is also the rudders an daggerboard, having to work both ways or lifted (lifted for rudders clearly)

 

Sure is. Harryproas use oversize rudders (no daggers required) mounted on the side of the long hull or on the beams so there are no holes in the hull below the waterline and the boards can kick up in both directions. The beam mounted rudders rotate through 360 degrees, the hull mounted ones are 2 way sections designed by Tom Speer, which work almost as well as NACA 0012.

 

Sorry for the thread drift. Maybe ask more proa questions at http://forums.sailinganarchy.com/index.php?showtopic=161235&hl=%2Bbucket+%2Blist+%2Bproa#entry4709952 Make the lee hull 3-4 times as long, scale up the rig and beam accordingly and make the little hull just big enough for 3 crew, their gear and a half a ton of water and have a go at the JV. ;-)

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^^^^^ +1. Please take the boat design stuff to another thread rather than pollute the IDEC RTW discussion.

 

With regards to that... wow what a nice lead but ouch. Both the South and North Atlantic weather patterns seem wack and not exactly favorable. Not sure this is as "in and bag" as folks seem to think. Kinda thinking otherwise but not my area of expertise by any means.

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What the north Atlantic looks like is not very important, and 10 days forecasts are not that reliable, but the south looks un-cooperative right now and for the next week as well.

Maybe they got a lucky unpredicted change and by the time they got to the equator don't lose more than 2 of the 4.5 days advantage that they have now.

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