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Vendee Globe 2020

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1 minute ago, noaano said:

Outer shell is the structure, more or less. Core is there just to shape the outer layer. Core can be air, or removable mould.

Not quite. Composite structures have foam core to carry shear loads - much like a steel I beam's web. It can be nomex or foam - and most definitely isn't air.

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1 hour ago, JonRowe said:

The accelerometers and rate gyros will all be hooked into the navigation system, that data is used by the autopilot, so I am making a massive assumption that they are canbus or N2K, or a similar marine protocol, they have ethernet in some scenarios but most systems do not use a standard stack

They absolutely use ethernet. It was mentioned the autopilot is linked to cameras, N2K does not have enough BW for this.

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5 minutes ago, Miffy said:

Not quite. Composite structures have foam core to carry shear loads - much like a steel I beam's web. It can be nomex or foam - and most definitely isn't air.

Depends on a structure, cannot say for sure without knowing. Strong carbon box beams and/or matrix structures for sure have air in the middle. 

Carbon fibers themselves are actually 99.9% or the strength of structure. Epoxy is just keeping them together. Core keeping them in shape, and/or separating the load bearing layers.

Modern carbon structure. No core:

CurvedBeam8ft.jpg.webp

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2 minutes ago, noaano said:

They absolutely use ethernet. It was mentioned the autopilot is linked to cameras, N2K does not have enough BW for this.

I agree, which is why I said "in some scenarios".

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36 minutes ago, troll99 said:
2 hours ago, k-f-u said:

I'm no expert in carbon structures whatsoever, but I don't understand why you carry an amount of repair material (read: weight) that is able to make the structure stronger than the original - in an area that was known to be fragile in the new gen foilers (cf. the italian's video). Why not make it stronger in the first place? Is it about saving weight? Not bitching, just trying to understand...

ha! it would be easy if it has been that simple. Obviously, computer models don't replicate reality. 

2nd gen boats rise higher and slam down. Unknown territories there... To keep low weight, you rather repair broken than oversize everything. Look at old F1 cars by Lotus and Chapman. They run "too light" cars and it would kill the driver instantly at a medium incident.

computer models don't replicate reality? Yeah right. Tell that ETNZ (among others).

The 2nd gen boats have been around for 1-2 years so plenty of data to be collected and shared within the class, with the architects, or across training mates in that time. Your "repair strategy" might work in an F1 circuit with a whole shore crew and several stages (see the Telefonica example), but the Vendee Globe is like the Rally Dakar in one big stage without pit stop and crew. Big breakdown = you're not gonna win.

Maybe Alex is paying a price being the outsider and not training with the guys based in france, plus a lot of downtime after the TJV.

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6 minutes ago, noaano said:

Depends on a structure, cannot say for sure without knowing. Strong carbon box beams and/or matrix structures for sure have air in the middle. 

Carbon fibers themselves are actually 99.9% or the strength of structure. Epoxy is just keeping them together. Core keeping them in shape, and/or separating the load bearing layers.

Modern carbon structure. No core:

CurvedBeam8ft.jpg.webp

Did you not see the boat or are you just googling aviation components and saying it is the same in marine builds?

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2 hours ago, JonRowe said:

the marine industry is heavily proprietary (with the exception of Signal K) because its hard to develop systems and stacks that work in marine environments.

These systems used, especially autopilots, are bleeding edge deep NN systems, prototypes not available for public. The stack used is for sure more IP/Ethernet than N2K, though it is interconnected. You just cannot feed enough data fast enough through N2K/canbus.

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4 minutes ago, noaano said:

Depends on a structure, cannot say for sure without knowing. Strong carbon box beams and/or matrix structures for sure have air in the middle. 

Carbon fibers themselves are actually 99.9% or the strength of structure. Epoxy is just keeping them together. Core keeping them in shape, and/or separating the load bearing layers.

Of course laid-up carbon layers, with multi-direction weave, can be made very strong and light, just like it's achieved in F1 or even hydrofoils.

But for general stiffening structure it makes sense to use quite thick sandwich panels that are going to achieve good stiffness and shear capacity due to their depth. And such panels can be manufactured at scale with some sort of honeycomb core and build costs would be much smaller.

In Alex' video the longitudinal girder structure is quite clearly made up of such sandwich panel, with the core between skins sealed with 'cap' carbon fibre weave layer/s.

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11 minutes ago, climenuts said:

Like the Columbia o-rings?

"According to Ebeling, a second conference call was scheduled with only NASA and Thiokol management, excluding the engineers. For reasons that are unclear, Thiokol management disregarded its own engineers' warnings and now recommended that the launch proceed as scheduled;[15][16] NASA did not ask why.[14] Ebeling told his wife that night that Challenger would blow up." https://en.wikipedia.org/wiki/Space_Shuttle_Challenger_disaster#O-ring_concerns

Management not listening to the engineers is a whole other issue. I'd hope Alex's team values his safety enough to listen to what the Engineers say.

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Seems like the cracks all radiate from openings in the beams which are there presumably to save weight. Is it close to correct to guess that this is all down to saving 10 lbs if the panel had not had the hole? 

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I think that vertical carbon tube on starboard with the wood wedge at the bottom is holding in place a repair that Alex has already completed. You can see some vertical carbon plates with bolts (note Alex mentioned "bolting" in the first message about the repairs) on that longitudinal.

Interesting that he did not mention this at all while showing the cracks in the center girder.

 

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3 minutes ago, loneshark64 said:

I was looking for the sailboat race and somehow wandered into the technical dick measuring thread. 

yeah, let's start a IMOCA Bricolage thread presented by PRB... and BOSS :lol::ph34r:

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19 minutes ago, TPG said:

No engineer is going to sign off on a repair thousands of miles away. Its buyer beware and keep the watertight doors locked.

They also aren't going to tell a competitor "If you do this, you will be good to sail in the southern ocean" unless they are pretty confident that the recommended repair will be good. They know he'll push the boat and that a competitive guy shouldn't be the one to make calls about risk and boat safety. 

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19 minutes ago, Miffy said:

Did you not see the boat or are you just googling aviation components and saying it is the same in marine builds?

This is just fine for structure for boat, provided you transfer the loads properly into this structure. Skin of the boat is different.

Btw as you can clearly see this is not an aviation component. There are no rivets. And no core.

IMG_3829.jpg

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19 minutes ago, troll99 said:

you want core in load areas, surely

Depends on a structure. You don't need core per se, it is just one option. There are multiple ways.

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13 minutes ago, k-f-u said:

Maybe Alex is paying a price being the outsider and not training with the guys based in france, plus a lot of downtime after the TJV.

Not enough time to break the boat with the rona. Or rather they broke a really really unexpected part that required a lot of time to repair.
I suspect there will be lessons learned for the keelbox design on the upcoming generation of boats. Esp. if they have good data from the crash or the forensics in the shed. Has been a while since the keel fell off an they got the boat back.

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31 minutes ago, noaano said:

Outer shell is the structure, more or less. Core is there just to shape the outer layer. Core can be air, or removable mould.

False.

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16 minutes ago, noaano said:

- Ben Lexen, 1982 

The man, the myth, the legend.

 

19 minutes ago, noaano said:

These systems used, especially autopilots, are bleeding edge deep NN systems, prototypes not available for public. The stack used is for sure more IP/Ethernet than N2K, though it is interconnected. You just cannot feed enough data fast enough through N2K/canbus.

I agree about the pilots, but there is also a lot of standard "off the grand prix" shelf like WTP, displays, interfaces, load cells. Sorry this has gotten way off topic from my original "I wouldn't blame the sensors, I'd blame the log settings".

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16 minutes ago, b3nharris said:

Is Alex sailing again? First time boat speed has been above 5-6kts. 

Screenshot_20201123-174553.png

Over the last half hour he's kept pace with or sailed faster than the boats closest to him (Boris, BV2 and AP). Looks like DIY-time is over.
image.png.2f1272e8eca084a7b112e48346358f72.png

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5 minutes ago, carcrash said:

False.

Well, not black and white. Carbon fiber structure can be done with or without core. Carbon being among strongest materials there is, it is hard to beat pure carbon structure for strength to weight. Adding core adds weight, so it lowers this value. It might bring some other benefits, but you can transfer the loads to the structure just fine without the core.

There are options. There is no single one right way to do things.

Modern carbon fiber structures for sure are moving towards coreless construction:

9TLabs.jpg

3D printing will change this even more. Interesting times.

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27 minutes ago, mario147 said:

Well, if I remember well when Telefonica made their repairs there we peanlized because of additional reinforce of a one design. I just couldn't believe it

Yup--in the 2014-15 VOR, with the first VO65s. Unpenalized repair was in the 'freighter' race, 2011-12 with the VO70s.: so much damage that time.

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14 minutes ago, b3nharris said:

Is Alex sailing again? First time boat speed has been above 5-6kts. 

Looks like it on the new report. About as fast as the boats near him.
About time. He is in the middle of that pack and there is not much wind any time soon.

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32 minutes ago, MastaVonBlasta said:

Would you expect these sailors to also be experts in composite design, analysis, build and repair?

I think from the safety standpoint allowing them to receive advice to preserve the integrity of boats is critical.

 

It's not as if he's going to make his boat faster or someone is repairing it for him while he's relaxing or sailing further

Just asking a question. From a safety standpoint and getting the sailors back to shore, I get it. The rules is what I was enquiring about.

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4 minutes ago, Chasm said:

 

Nice selection of bits to use for repair!

Interesting that he called equal angles girders - can be quite effective in stiffening.

So much work to do in cutting, prepping, screwing and bonding. Then how long would it need to cure for?

If he's really underway now as some have been observing, then he'd managed to get it done pretty quickly...

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44 minutes ago, noaano said:

Depends on a structure, cannot say for sure without knowing. Strong carbon box beams and/or matrix structures for sure have air in the middle. 

Carbon fibers themselves are actually 99.9% or the strength of structure. Epoxy is just keeping them together. Core keeping them in shape, and/or separating the load bearing layers.

Modern carbon structure. No core:

CurvedBeam8ft.jpg.webp

False.

The green in the above image is core. To core keeps the inner and outer carbon skins at a precise distance apart, acting as the sheer web of an I beam. This beam consists of four surfaces, each using foam as the sheer web to keep the shape of those skins.

Carbon provides very close to zero compression strength unless the fibers are kept in the proper location. The epoxy and core keeps the carbon filaments in the precise location so they can absorb any compression load whatsoever.

Under tension, no core or even epoxy is required. At the ends of a cable, sure.

Small amounts of compression can be handled by a carbon sheet, but the amount is tiny unless the unsupported length is very small. As you can see from the above part, the distance that can be supported without core is dramatically less than the shorter dimensions of this part (height and width). If just the carbon was enough, this small part would not have core.

This shows how small a box section must be to work without core: very small, a few inches at most. To be stiff enough without core, many more layers of carbon are needed, making the structure heavy. Hence, any structure that needs to absorb compression (nearly anything that needs to keep a shape) that is larger than, say, a coffee cup, will be cored, will be curved quite a lot, or it will be too heavy.

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1 minute ago, MastaVonBlasta said:

 

So much work to do in cutting, prepping, screwing and bonding. Then how long would it need to cure for?

If he's really underway now as some have been observing, then he'd managed to get it done pretty quickly...

I think there's quite a bit of delay from when AT did the work & when he's putting the videos out - and it is a good thing the inside of the boat is so warm, though the humidity won't be helpful and might cure it too quickly. 

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18 minutes ago, noaano said:

Depends on a structure. You don't need core per se, it is just one option. There are multiple ways.

Look again at the pic I posted.

30 times higher strength without almost increase at the weight. 

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2 minutes ago, inneedofadvice said:

Just asking a question. From a safety standpoint and getting the sailors back to shore, I get it. The rules is what I was enquiring about.

The NOR have something to say about that:
 

Quote

4.3.5 Remote technical advice 
Remote technical advice, defined as “any information given by a support person (within the meaning of the RRS) enabling the skipper to solve, alone and with the means available on board, a technical problem on the boat” is authorized.  
It is prohibited: 
• Technical advice shall not give information to the skipper about the precise timing to carry out repairs in order to optimize the trajectory of the boat and minimize its loss in distance.  
• Technical advice shall be restricted to actions of repair; under no circumstances shall it be connected with manoeuvering or operating the boat, particularly to compensate the loss in performance following technical damage.   
• Remote control, defined as « any external human and/or technological intervention on the boat, including sending personalized updates by email, allowing remote action on one or several elements, equipment, or settings of the boat in place of the crew”.  
• Downloading software or updates by the boat is prohibited (except for those publicly accessible, referenced and subject to authorization by the race management before 
downloading).  
It is authorized to: 
• Are authorized all oral or written exchanges of photos and videos aimed at enabling the skipper and its team to describe a technical problem and offer a method of repair so that the skipper can make the repair autonomously. 
• Any technical advice to the skipper shall be accessible at all times to the race management. If a group of technical discussion through instant messaging (such as Whats App, Telegram, etc.) is set up, the race management shall be included in it.

 

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11 minutes ago, Chasm said:

 

Can someone say whether this was taken in the evening or in the morning based on the sun?

To me, it seems like evening, the boat was heading south west and the sun was coming from the right side...

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49 minutes ago, noaano said:

Modern carbon structure. No core:

  CurvedBeam8ft.jpg.webp

You go from two coreless skins with air bullshit to a 4 sided beam with no core/air to make your point about no core/air for two skins. 

Wriggley.  How about thinking about what you say first.

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40 minutes ago, k-f-u said:

computer models don't replicate reality? Yeah right. Tell that ETNZ (among others).

The 2nd gen boats have been around for 1-2 years so plenty of data to be collected and shared within the class, with the architects, or across training mates in that time. Your "repair strategy" might work in an F1 circuit with a whole shore crew and several stages (see the Telefonica example), but the Vendee Globe is like the Rally Dakar in one big stage without pit stop and crew. Big breakdown = you're not gonna win.

Maybe Alex is paying a price being the outsider and not training with the guys based in france, plus a lot of downtime after the TJV.

Etnz? Are you kidding? You have no idea about Imocas.

My point about F1 that it is a mechanical sport where everyone chases weight. Even if it means risking your life. 

However, you replied to all that in the last sentence without knowing that. :lol:

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looks like HB is still drifting, only the others are drifting too. 

But--looks like that cold front can't *quite* nail the leaders. 2088756511_ScreenShot2020-11-23at11_19_59AM.thumb.png.9bd7e5963d789441ae4832c58eee41f3.png 

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7 minutes ago, carcrash said:

The green in the above image is core. To core keeps the inner and outer carbon skins at a precise distance apart, acting as the sheer web of an I beam. This beam consists of four surfaces, each using foam as the sheer web to keep the shape of those skins.

Carbon provides very close to zero compression strength unless the fibers are kept in the proper location. The epoxy and core keeps the carbon filaments in the precise location so they can absorb any compression load whatsoever.

This discussion does not go anywhere. Core can be used or done without core. Care must be taken to transfer loads so that compression load does not break the structure, but this can be done with or without a core. In future when pure carbon isotruss can be 3D printed into any shape, there is even less need for a core.

There are multiple options, and multiple ways of doing things.

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Blah blah blah blah blah - neither here or there because AT's boat has engineered composites with foam and nomex core so can we move on.

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9 minutes ago, troll99 said:

Look again at the pic I posted.

30 times higher strength without almost increase at the weight. 

Depends on the load applied. Cannot compare apple-apple. No one in their right mind would do solid carbon structure you are comparing against, what sense would that make?

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Keep swinging, dicks. High points of the threads on Ocean Racing Anarchy, IMHO. 

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Just now, Miffy said:

Blah blah blah blah blah - neither here or there because AT's boat has engineered composites with foam and nomex core so can we move on.

Lets continue following the race, I agree!

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1 minute ago, noaano said:

Depends on the load applied. Cannot compare apple-apple. No one in their right mind would do solid carbon structure you are comparing against, what sense would that make?

For your own sake, stop saying that. There are other people who are more knowledgeable about that kind of stuff. Just stop!

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Meanwhile, back at the race, I'm wondering why Sam and Louis Burton have gybed more south.  Wouldn't that head them straight into the light air?

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23 minutes ago, no_ballast said:

I think that vertical carbon tube on starboard with the wood wedge at the bottom is holding in place a repair that Alex has already completed. You can see some vertical carbon plates with bolts (note Alex mentioned "bolting" in the first message about the repairs) on that longitudinal.

Interesting that he did not mention this at all while showing the cracks in the center girder.

 

These cracks in the central longitudinal bulkhead, that he presented as the damage, are only some stress cracks caused by the skin below moving to the right on each slamming bounce. I assume it happened over the long period and there is no such cracks on the right side of the central. But the real damage was in the right longitudinal beam that is seen under compression and fixed by some bolts. This allowed the skin to flex in and by doing that it was pulling the central to the right.

So I agree. The major damage is fixed and he will resume racing after the latest position update today. The central is more cosmetic and better to fix while headsails are under load as this will compress the upper part of central bulkhead and pull the skin below. This will tighten the cracks closed and these can be laminated over.

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2 minutes ago, Corryvreckan said:

Meanwhile, back at the race, I'm wondering why Sam and Louis Burton have gybed more south.  Wouldn't that head them straight into the light air?

Ultimately, whoever's below about 35S in 3 days is going to be in the passing lane...  At some point, southing has to take priority over easting.  It's a matter of who wants to make that call when.

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If I were AT I think I would accept Neal MacDonalds call an the structures, not many Naval Architects who have as much practical experience ... having said that a lot will depend on the prep, and as has been said, where is the next weak point?

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Ouch..

That does not look like something easy to make it 'stronger than before'..

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1 minute ago, Miffy said:

Between all of the boys - I trust Sam's weather routing above all.

Above JLC?  Dude looks to have successfully cut the corner and held off a pack of foilers for 2000nm or so.  In the South Atlantic, inside the curve has won out big time.  

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3 minutes ago, stief said:

Keep swinging, dicks. High points of the threads on Ocean Racing Anarchy, IMHO. 

Swinging dicks is last shot in the career locker for aging pro golfers.

They suddenly appear buffed with a sock full of sand stuck down their pants ...sticking the pic on their Instagram account. 

Fans go wild for X-rated detail in Greg Norman’s shirtless photo

IMG_20201124_033222.jpg

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34 minutes ago, noaano said:

Lets continue following the race, I agree!

Do you know how many times you have said that? 

Take a fucking self awareness pill.

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4 minutes ago, Roleur said:

Above JLC?  Dude looks to have successfully cut the corner and held off a pack of foilers for 2000nm or so.  In the South Atlantic, inside the curve has won out big time.  

I think part of the routing decision was also contingent on what people were willing to do to their boats and the expected performance differential they're looking forward in the southern ocean - don't get me wrong, JLC is the boss and much respect to him for what he's doing - but Sam has also been around routing for other ppl's record chasing efforts for a while now.

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3 hours ago, Chasm said:

What is going on with the additional carbon rods(?) to the left and right when he enters the compartment?
Storage for spares or gluing the skin back onto the ring frames?

As far as repairs to the frame go, I guess that depends how much of it is foam.

I think those are the "girders" he mentions. Perhaps lashed to stiffen the remaining structure while he works on putting more epoxy and carbon all over the centerline structure. Looks like that entire structure is nomex cored, as it is so thick.

As we all now know, strength increases rapidly with thickness of core, hence that very thick core for all the structural elements.

But it is also clear that the amount of carbon on the faces and caps was not enough. The caps really take the load, of course, but the faces are needed to distribute that load. This is actually an example of how S-glass or E-glass can be better than carbon for those faces, as faces must deform a bit, and only through deformation is the load distributed through the structure.

You can see how thick the caps are, and they broke too.

Hence, I think fixing the faces is pretty easy -- two layers to  strengthen of the faces where they broke, as the lamination Alex can do is not as good as the lamination done in the boatyard.

Fixing the caps seems the tough problem: those caps are thick carbon, many layers. Probably why AT mentioned using carbon plate. I bet they will need to be bolted, but man, that is a tough engineering problem: bolts concentrate load, and due to the stiffness of carbon, that load does not distribute well at all. Without a 3D structural model, I would throw in the towel. AT's team does have 3D structural models and analysis abilities, so I think a 120% or maybe 200% solution has been found. Heavy, sure, but so what.

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19 minutes ago, Miffy said:

Between all of the boys - I trust Sam's weather routing above all.

Agree. She was a key part of Coville's solo round the world sailing record in 2017, and many more projects. She knows the routes south.

Quote

His shore crew and weather routing team were a key part of his support network. Coville’s routing is led by Jean-Luc Nelias, his right-hand man for many years, who sailed with him on board both Groupama 4 in the Volvo and numerous double-handed races. A second viewpoint was constantly provided by either Thierry Douillard or Sam Davies.

Besides crunching weather data, the routing team played a vital role in gauging Coville’s own limits and acting as a sounding board when stress levels peaked. “Jean-Luc is the one who knows Thomas really well, and so he knows when he can push him and when not,” explains Davies.

“Obviously there are moments where you have to push because you’ll drop out of the system or get caught up by no wind, and there are other moments when, yes you could go faster but it doesn’t really make a massive difference.

https://www.yachtingworld.com/special-reports/how-thomas-coville-set-the-solo-round-the-world-sailing-record-105355/2

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The breakage is an engineering failure plain and simple.The boat has had no collision

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5 minutes ago, The Tug said:

The breakage is an engineering failure plain and simple.The boat has had no collision

I was wondering: would a full scow (like minis) be competitive with foilers?

Looking to what JLC is doing with a non foiler, I would say that a scow bowed IMOCA would probably be. May be not in top speed, but in average.

And wouldnt be easier to evaluate stresses on that kind of boat?

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Fine gybing duel seen playing back the tracker. . Charlie's extra two gbyes didn't stop him taking the lead, but must have hurt his body.

IMG_40DCDE68DA8E-1.thumb.jpeg.46ff8ed452abfb137645f9194fa0d586.jpeg

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5 minutes ago, The Tug said:

The breakage is an engineering failure plain and simple.The boat has had no collision

It does look like that

These boats and the Volvo boats have suffered a lot from slamming loads causing delamination in the bow but this looks scarcely almost like a rig load issue to break a full height longitudinal in the bow . The structure looks beautiful but if they have not hit anything .... a bit scary.  Good luck and I am not grinding carbon in the bow in that heat.

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Of course, a slamming load and a rig load could presumably happen happen simultaneously, and likely multiply up the effect.  Catch a gust right when a wave stops the bow.

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Pip's party. Needle teasing. (not yet up on YT, so sorry for the tweet link) fixed

 

 

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1 hour ago, Chasm said:

 

Extraordinary transparency compared to AT's broken foil coverage, where this board was rampant with speculation about the extent of the damage.  Quite a change in approach,  along with Alex saying "keep watching", I guess he's going explain the entire repair and results. Really too bad about the breakage and ~400 mile loss, but the loads from sailing on foils are relatively new, bleeding edge keeps things interesting.

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4 hours ago, Icedtea said:

Yeah....that boat is fucked

Agree. I hope he gets around safely but there is no way he can push it hard anymore even with repairs. That needs a full proper rebuild.

New bonds may pop under the fast and harsh stress loads of these beasts. Would like to see more Kevlar in there as well. Safe travels Alex.

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4 minutes ago, Irrational 14 said:

Would like to see more Kevlar in there as well

lol no kevlar has no business in a class where carbon composites are allowed.

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Sure would like to see photos of the leaders if they were close enough during the pass, but they seem like the quiet types.

And for Armel, head west young man. Trying the big end-around, while Charal hugs the east side. 

This is a fun race to watch.

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4 hours ago, LeoV said:

Do I see a wood wedges supporting a carbon pole to release the stress ? Amazed he has them onboard.

Who goes to sea without a collection of wedges and poles? The wedge is such a useful tool .....

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2 hours ago, noaano said:

They absolutely use ethernet. It was mentioned the autopilot is linked to cameras, N2K does not have enough BW for this.

More likely a meshed radio network of some sort for the sensors. Zigbee or bluetooth .. much lighter than running cables. Ethernet will be used on the systems for sure. Radar etc are all ethernet these days.

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1 minute ago, steinbrenner said:

to be trusted? Max bow height still -1,30 m

Unless he's now a submarine doing +11 kts perhaps -1.3 is the new normal...or perhaps a damaged sensor?

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1 hour ago, pilot said:

These cracks in the central longitudinal bulkhead, that he presented as the damage, are only some stress cracks caused by the skin below moving to the right on each slamming bounce. I assume it happened over the long period and there is no such cracks on the right side of the central. But the real damage was in the right longitudinal beam that is seen under compression and fixed by some bolts. This allowed the skin to flex in and by doing that it was pulling the central to the right.

So I agree. The major damage is fixed and he will resume racing after the latest position update today. The central is more cosmetic and better to fix while headsails are under load as this will compress the upper part of central bulkhead and pull the skin below. This will tighten the cracks closed and these can be laminated over.

Except that if I interpet your theory correctly that damage would have occrred on Starboard tack and he has been on Port tack for most of the race. ... ?

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1 minute ago, steinbrenner said:

to be trusted? Max bow height still -1,30 m

The bow sensor is not to trust. 

I say good epoxy because it cured faster than I thought.

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23 minutes ago, Miffy said:

lol no kevlar has no business in a class where carbon composites are allowed.

Kevlar has its place, but it always seems to be used in the wrong way... or as a tough barrier layer.  Kevlar is abysmal in compression and it’s use a bullet proof vest has had many people misunderstanding how it functions in that case and how it’s not applicable to use in a similar fashion within a composite structure.  Used purely in tension however, Kevlar can outperform carbon and can be quite useful.  Best not to fuck though, because if you have to repair it with he it’s a world of hurt.  It’s also hard to bond things to Kevlar properly. 

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2 hours ago, Chasm said:

 

Lucky it looks to be a centreline longit, as he says he is going to use up most of his spare bits of carbon. Just hope it doesn’t create too much step transitions and attract too much load to those areas, which would then be the next areas to fail. Fingers crossed!!

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given the heat and humidity in the cave, i bet the goop was kicking as he was tightening the clamps.. 

  i'll be shocked if that fix makes it around the marble...

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I am 99% sure that this is a "get to cape town" fix and the team (rightly) playing it up for media coverage. 

 

This plays much better than a "boat is fucked, we're limping to cape town" story. 

 

They are masters of PR, and are making the best of a bar situation. 

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2 minutes ago, Icedtea said:

I am 99% sure that this is a "get to cape town" fix and the team (rightly) playing it up for media coverage. 

 

This plays much better than a "boat is fucked, we're limping to cape town" story. 

 

They are masters of PR, and are making the best of a bar situation. 

the glass is half empty or full. :lol:

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2 hours ago, MastaVonBlasta said:

When Alex was pointing out all the cracks the video was cut off just before he was about to point towards the crack further aft, near the hull bottom

All in all that entire girder section has cracks

 

image.thumb.png.cec90870a7c149800233ff013164ab7e.png

That crack in the lower right is in addition to what is marked below and point out by Alex:

image.thumb.png.278801e5372495b3b9abb9c5b5be75f9.png.

I am sceptical about these cracks, to repair them doesn't solve the structural problem.
Perhaps a too stiff material isn't suitable for the slamming those bows take when foiling through the waves at 30 knots.
The elascticity of high performance iron, is better to deal with the peak loads.
He's is not going to make the finish.

Well seamanship to detect the cracks. It's not see no evil hear no evil.
Too bad, another set back in his career.
 

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Crisis averted for Jean LeCam

Quote
Vendée Globe: "I tested with the watermaker, I can finally have a good coffee"
By Jean Le Cam  November 23, 2020 at 6:00 pm
Jean Le Cam, aboard his monohull, this Sunday. Jean Le Cam, aboard his monohull, this Sunday. Photo Loïc Venance. AFP
 

Vendée Globe: "I tested with the watermaker, I can finally have a good coffee"

Engaged in solo racing aboard Yes We Cam!, his old-generation sailboat, Jean Le Cam regularly sends his news from the ocean. This week, it is in the Atlantic, at 24°02 south and 24°35 west.

"It's Monday, November 23 aboard Yes We Cam! And imagine that we are in third place among all the boats in the Vendée Globe. Our goal being to be in the top three of the drift boats, well here we are third in all boats. So that's it, that's great news. It's even something that in your dreams, you don't even imagine! Well, that's the reality today.

 

machine trans from here

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15 minutes ago, Icedtea said:

I am 99% sure that this is a "get to cape town" fix and the team (rightly) playing it up for media coverage.

This plays much better than a "boat is fucked, we're limping to cape town" story.

They are masters of PR, and are making the best of a bar situation. 

Totally Agree!... seems 2020VG is fucked and over (again), they could also repair in Durban or CapeTown and go to smash his own record, etc. (he definitely has the media coverage exposure and ROI numbers in the heat.. even out of the race)

MoneyCount.gif.e65e71e9653b835ee32699b74f567686.gif

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Looks like the big Fr names are chiming in, like Peyron and Mich D. Good benchmarks.

Quote

DESJOYEAUX BELIEVES THE REPAIR OF THOMSON AND SEES IT BACKGROUND
   
By Martin Couturié
Updated on 11/23/2020 at 7:58 pm - Published on 11/23/2020 at 7:42 pm
Joined by Le Figaro, the two-time winner of the Vendée Globe believes that the Briton can succeed in his repair and go back in the race to try to win the round the world race.
Joined by Le Figaro this Monday evening, Michel Desjoyeaux said, after seeing Alex Thomson's video showing the damage aboard his Hugo Boss monohull, that he believed it possible to repair the Welshman successfully. "What is affected is a longitudinal bulkhead in the middle of the bow, about the forward quarter of the boat. The partition plating is cracked as is the wall of this bulkhead. He could not continue without doing anything, "explained the two-time winner of the Vendée Globe and the three-time winner of the Solitaire du Figaro.
And the best record of solo offshore racing, also a construction site boss, added, regarding Alex Thomson's repair: "It's smart to repair with a large plate that he will glue and bolt. It's not complicated to do in port. However, the plate and partition must not move at sea during the catch. Alex must wait until the resin dries and is solid to leave."
So makeshift repair or real repair to go back in the race, and who knows how to win? Michel Desjoyeaux is optimistic: "I believe in it, I am quite confident if he has enough equipment to repair, which seems to be the case. There is something to do that will be stronger than before. And the finish line is in Les Sables d'Olonne, not at Cap de Bonne Espérance. A lot of things can still happen. And as with Jérémie Beyou, it's great for Alex to be able to go back to the race after repairing. That's the Vendée Globe spirit... "
Fifth in the 6 p.m. standings, 382 miles behind Charlie Dalin, the new leader, the Welshman can, according to Michel Desjoyeaux, still dream of victory.

machine trans from here

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1 hour ago, The Tug said:

The breakage is an engineering failure plain and simple.The boat has had no collision

It had a collision that ripped off its keel. 

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