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  #61  
Old 01-28-2017, 12:20 PM
cavalier mk2 cavalier mk2 is online now
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When are they going to try? Certainly the weather windows this season have been good.
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  #62  
Old 01-28-2017, 01:01 PM
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The Spindrift team are planning to go on standby for a record attempt in Winter this year.
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  #63  
Old 01-28-2017, 01:21 PM
cavalier mk2 cavalier mk2 is online now
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Thanks Corley, I'm assuming you mean the Northern hemisphere winter 17-18.
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  #64  
Old 01-28-2017, 01:28 PM
Ilan Voyager Ilan Voyager is offline
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Quote:
Originally Posted by cavalier mk2 View Post
Sometimes less is more! This is a good idea for cruisers as well. It tends to get lost in pile it on marketing.
I do heartedly agree. I have seen many people dreaming of circumnavigation selling their heavy displacement big sailboat after seeing that the boat was truly exhausting, and very expensive to maintain. And discovering that a medium sized medium displacement modern sailboat is easy to sail, less expensive to maintain and faster...Plus the fact that for a true sailor a floating condo with double berths is totally useless for real navigation.
Same for the cruising catamarans.
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  #65  
Old 01-28-2017, 01:32 PM
Ilan Voyager Ilan Voyager is offline
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The modified Spindrift can be the gun as it has the longest hulls, thus the biggest potential of speed on such slim displacement hulls. We have to give the credit of the idea to Joyon when he thought over the ideal trimaran for a solo circumnavigation and arrived to the conclusion that simpler and lighter was the solution of the optimization.
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  #66  
Old 01-28-2017, 02:01 PM
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Quote:
Originally Posted by cavalier mk2 View Post
Thanks Corley, I'm assuming you mean the Northern hemisphere winter 17-18.
Yes, that's correct.
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  #67  
Old 01-29-2017, 03:59 AM
semelis semelis is offline
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Spindrift 2 follows more or less the proportions of the boats that Joyon and Thomas had, while the ex-Groupama 3 that Frank Cammas commissioned has a 3x2 proportion more in line with the ORMA tris he knew so well. With more or less the same 100 feet length and sail area for solo sailing, it proved in the Route du Rhum (twice) that the extra width was a killer.

While Spindrift 2, with the extra length compared to IDECsport, may have an advantage in potential speed, I've been convinced that the 3x2 proportion must be quite close to the optimal one.
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  #68  
Old 01-29-2017, 08:42 AM
Ilan Voyager Ilan Voyager is offline
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Spindrift is totally different. Groupama 3 and Idec Sport have similar proportions, because they are the same boat simply modified.... The ratio width/length is around 72-75%. This tri is closer to 4x3 than 3x2. Displacements and surface sails are similar. The tri was designed and modified by the the same NA team. So Idec already proved the concept.ratio/width above 70%
Spindrift has the lowest ratio width/length 57%, but with a similar width around 23 m. Remark that all these maxis have the same width around 23-23 meters, it is not a coincidence, it's the actual limit of engineering the arms in carbon with the desired springness and damping. without going to far bigger and heavier arms.
But Spindrift is about 30% longer, that's a lot, but only 27% heavier. As the displacement is proportional to the cube of the size, with the same ratio displacement/ length as Idec Spindrift should weight around 35-39 tons, but it weights only 23...
Spindrift is a very light boat for its size, that means that the hulls are slimmer with a similar or maybe smaller wet cross section, with probably a higher CP. That explains its phenomenal top speed and records.
The original BPV, renamed later Spindrift, had a visible option light/medium wind, shown by the huge surface of sail, the lightness and very tall mast. He got the biggest usable "engine" by a a very experimented team. Surely there has been some tense moments with such a rig.
The modified Spindrift will have a similar lateral stability ratio as Idec, but a far better diagonal stability, probably a lower center of sail, slimmer and 30% longer hulls...And surely better sea going and damping ability, a very important factor. The saving of weight of the rigging will be consequent, the length of the boat permits to put horizontally more sail while keeping a lower center of sail and with a better angle of usable forward efficiency.
There are many options, I guess that the CPUs of the computers of the NA team had a hard time calculating all these possibilities. And the structural engineers have worked all that in detail.
Do not forget that all all these tris had been designed by the same NA team who has all the records. True ciphers, detailed reports of the trials, of the racing behavior and of structural expertises after the races...That becomes far easier as there is no guessing even educated...These tris are now designed and calculated by a bunch of specialists, and built by shipyards of aerospace level.
Spindrift is the gun. With a little meteo luck...
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  #69  
Old 01-30-2017, 03:26 AM
semelis semelis is offline
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If the 22~23 meters width is an engineering constraint, then Spindrift2 is definetly the tool for the job.

Didn't realize that G3/IDECsport dimensions were really past .667 to .714. , old one was Nigel Irens 2007 design also used in Sodebo: width: 15.5(5) m , length central hull: 29.7 for IDEC, 32 for Sodebo.
15.5/29.7=.52
15.55/32=.486
Beeing the floats quite shorter, I'm not sure how to compare this, in 2007 IDEC's case:
15.5/24.5=.63
37/23=.62 for BPV / Spindrift2
I can't find the floats length for 2007 Sodebo, but the proportions are quite close, so BPV/Spindrift looks like a scaled up version of 2007 IDEC-Sodebo, while G3/IDECsport looks like an ORMA and has the floats about as long as the central hull.

Displacement is proportional to the cub of the size if it scales on the 3 directions, Spindrift mainly scales on longitud compared to G3, almost not in width, and no sure, for the hull, in height.
30% longer should be more or less 30% heavier if the other dimensions are not increased.
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  #70  
Old 01-30-2017, 06:03 AM
Ilan Voyager Ilan Voyager is offline
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Quote:
Originally Posted by semelis View Post
If the 22~23 meters width is an engineering constraint, then Spindrift2 is definetly the tool for the job.

Didn't realize that G3/IDECsport dimensions were really past .667 to .714. , old one was Nigel Irens 2007 design also used in Sodebo: width: 15.5(5) m , length central hull: 29.7 for IDEC, 32 for Sodebo.
15.5/29.7=.52
15.55/32=.486
Beeing the floats quite shorter, I'm not sure how to compare this, in 2007 IDEC's case:
15.5/24.5=.63
37/23=.62 for BPV / Spindrift2
I can't find the floats length for 2007 Sodebo, but the proportions are quite close, so BPV/Spindrift looks like a scaled up version of 2007 IDEC-Sodebo, while G3/IDECsport looks like an ORMA and has the floats about as long as the central hull.

Displacement is proportional to the cub of the size if it scales on the 3 directions, Spindrift mainly scales on longitud compared to G3, almost not in width, and no sure, for the hull, in height.
30% longer should be more or less 30% heavier if the other dimensions are not increased.
The hulls are roughly scaled, not the arms which have to be built to handle the increase of displacement, thus the stresses. That gives with the same coefficients of security something around 30 to 39 tons. I'ts a very rough estimation.
32 to 39 tons was the real displacement of the big maxis of the first era, like the catamaran Orange II, which is now the cruising boat, probably the fastest of the world, of Francois Bich, the heir of the Bic industry.
It's technically almost impossible for the moment to build a 4/3 maxi of 40 meters, unless a huge increase in weight, new hardware, new sail clothes and dozens of sailors to handle the monster. And there are cost constraints.
Besides with a length of 40m, there is no need to get the brutal and enormous stability moment of a 30 meters width, which implies the total rethinking of everything.

The small increase of weight of Spindrift originates simply as the hulls have similar cross sections as Idec Sport/Groupama 3 but are 30% longer. Just one dimension; a piece of hull in the center part of the hulls. After you tweak all that a bit, recalculate the arms, make a choice of stresses dissipation by a very slightly increased flexibility, which is interesting for keeping the angle attack of the foils of the submerged ama under sail stresses, a bit more carbon in the strategical points to keep the tall big rig on the deck, and the bows with the hulls. Et voilą, zis iz the rezipee to gett eazily espead. (heavy French accent, I can joke as I'm French and have a thick accent).

The first Idec (16.5 m wide) designed by Irens and Cabaret is a totally different tri of the tris designed by VLDP. The philosophy of Joyon, not a young man, was to get the "cheapest", simplest and easiest to sail maxi trimaran for a solitary. It's an ultralight only 12 metric tons for a 29.5 m length.
That shows the influence by the width of a tri on the weight. With a similar length, with a 16.5 width you get safely 12 tons, with 22.5 meters you need 18 tons.
The first Idec is a very "tender" and "soft" sailboat compared to Groupama 3 far more powerful. That is relative 99.8 % of the members of the forum, including myself, would need pampers while trying to sail alone Idec/Sodebo in a 10 knots soft zephyr on a mirror sea.
The 60 feet were totally bestial with big motorcycle accelerations and harsh reactions. I can say it first hand, as I have been "guest sit down here do not touch anything" on several 60 feet. The 40 feet were sweet baby girls compared to these wild 60 feet monsters, I had a rather good experience of sailing the F40s so I can compare the sensations. I can only imagine a AC72, that must be sometimes pure terror.

The length of the amas of BPV/Spindrift is 37 meters, 92.5 % of the length of the main hull. The first maxi Idec/Sodebo 24.5 m, only 84.5% of the 29.50 m of the main hull. 8% It's a huge difference. The ORMA tris were generally from 90 to 95%.
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  #71  
Old 01-30-2017, 11:32 AM
semelis semelis is offline
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The huge difference between amas and main hull of the maxis Idec/Sodebo compared to the ORMAs surprised me, BPV reduced a bit the disparity, but still it's apreciable in the photos. Lastest maxis/ultimes seem to go this way, with the new hull for ex-Geromino shorter than the original. Of course that saves weight, but I wonder whether the confused-sea-state capabilities are not as much enhanced by the long central hull if the ama is a lot shorter, and so the extra weight is not as useful as it was thought ?
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  #72  
Old 01-30-2017, 12:11 PM
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Doug Lord Doug Lord is online now
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Flying Tri's

Spindrift and Banque Populaire IX are set up to fully fly in the right conditions and that decision affects a lot of aspects of their design since a single ama foil will be able to support most of the weight of the boat.
The uptip foils, both have been fitted with(along with rudder T-foils), allow full flying with automatic flight altitude control by the lee ama foil. This will be at least as big a transformation of big tris as the dali foils have been to the IMOCA 60's!

Banque Populaire IX Fitted With Uptip Ama Foils

Spindrift Being Fitted With Uptip Ama Foils
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  #73  
Old 02-08-2017, 06:24 PM
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Joyon Interview

Francis Joyon speaks of the future(flying)!
http://www.sailingworld.com/qa-with-...s-joyon#page-2
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  #74  
Old 02-09-2017, 08:23 AM
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Official Record--IDEC

From Scuttlebutt Europe:
The WSSR Council announces the establishment of a new World Record:
Record: Around the World. Outright
Yacht: IDEC. 120 ft Trimaran
Name: Francis Joyon. FRA and 5 crew
Dates:.16th December 2016 to the 26th January 2017
Start time: 08;19;00 UTC on 16/12/16
Finish time: 07;49;30 UTC on 26/01/17
Elapsed time: 40 days 23 hours 30 minutes and 30 seconds.
Distance: 21600 NM
Average speed: 21.96 kts
Comments:. Previous record: Banque Populaire 5. Loick Peyron. FRA. Jan 12. 45d 13h 42m 53s

John Reed
Secretary to the WSSR Council
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  #75  
Old 02-09-2017, 04:41 PM
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WOW. Elapsed time: 40 days 23 hours 30 minutes and 30 seconds.

Now you know why the board members of the CYCA won't allow multi's in the Sydney/Hobart race.
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