Vendee Globe 2020

[noaano 135]

Show Replies

1 hour ago, JonRowe said:

Depends on the system, if the device doesn't support logging itself or the logging is done via a unified system (it'll be linked into the B&G for display for example)  then it might be the log doesn't even have the instantaneous values, and is only logging information given to it at the sample rate set.

As far as I know Expedition for example logs at the sample rate set, and doesn't store min/max, I don't know about Adrena I've never used the paid for version.

 

Yes, I don't really know what sort of datalogger they use, but with strain gauges and accelerometers and rate gyros you most definitely are interested in maximum values for the sampling period.

Many "normal" dataloggers certainly do have option for recording this as well.

 

I guess I would choose something like this for this use, it has expandability, swappable/expandable memory, network remote access and a local display for quick look on values:

[wharris87 15]

 

 

[yl75 1,027]

Wow, that's really serious stuff ..

Does Alex do a daily check ? Or not ?

[stief 3,650]

Finally 4 of the cracks shown. Reassuring that "the boat will be as strong if not stronger than before" Good that he took the time to mark them

[noaano 135]

Someone should submit a proposal to ICEYE to take a few tracking radar images of VG fleet:

https://hubs.li/H0Bnyqz0

Resolution should be enough to see the boats and maybe also see the sea state as well:

Would be interesting! I wonder if you could see individual wake behind a boat

[MastaVonBlasta 108]

5 minutes ago, wharris87 said:

 

 

Feck me that's a lot more substantial than I imagined....

Main longitudinal frame broken through top and bottom braces... I'm sure several sheets of carbon can be lapped on, but... I wouldn't want to head in Southern Ocean when such damage can happen even on the way there!

 

I don't know what they've put into Alex' food bags... If I were him my mood would have been quite a bit lower...

Amazing. Hope he can keep it up, effect a good repair and keep going around the world

[Haji 333]

That center bulkhead/girder must take the aftward loading of the fore stay.  And possibly the compression of the bowsprit as well?  Yikes. 

[Chasm 596]

Looks like no half measures for Alex.

[Icedtea 144]

9 minutes ago, wharris87 said:

 

 

Yeah....that boat is fucked

[JoeBleaux 45]

Video of the damage

 

...oof. 

[BozoC 112]

First, thanks to AT for showing the cracks so openly. To be honest, it looks worse than expected and I don't see how a repair done in the middle of the Atlantic can definitively solve such problem. (Adding and gluing pieces of carbon plates does not make it stronger, it just repairs the crack).  Good luck with the repair but I am a little bit concerned for remaining 20000 nm.  

[bucc5062 169]

That is some pretty impressive damage, but I'll take AT at face value that he can repair the boat enough to go full bore again.  The only question will be when?  I read here that 24 hours to cure so I guess when we see him pick up speed again he'll be back in the game.  If he can get up to speed in this current group it will be a good view of if he can run full out because I would suspect at 100% HB could pull away.

 

I like his attitude.

[noaano 135]

14 minutes ago, MastaVonBlasta said:

I don't know what they've put into Alex' food bags... If I were him my mood would have been quite a bit lower...

 

It is calles 'Pilot's Salt' in the professional circles....

The packing reads: "Alertness aid," to be taken "to maintain wakefulness" -- but, it continues, "only from time to time"

 

[Chasm 596]

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.

[yl75 1,027]

I don't think this happened during Theta considering how extensive it is, but then when ? The day before he stoppped ? how was the sea state then ?

[OPAL 188]

In the meantime, news from no Bother Boris. (80 days!)

Coordinates: 24°30.04’S – 026°36.24’W

“Good morning!

Good week to you all. 19.856.4 miles to go for us. 18.3 % of the Race distance done.
End of this week – Friday midday We will be in the southern ocean. 10 degrees temperature. Strong winds from behind. Albatrosses.
This morning I take out day 16 – last day from food bag 1 (out of 5 bags).

Tonight I am at 20% food consumption. (Actually have a solid stack of left overs put aside). Therefore well on track for a 80 day race food plan with margin for more if needed.
With the slow first week compared to 2016 and slow South Atlantic 80 days is very likely.  I say 27th January as a preliminary eta. Can’t wait ha”

[jack_sparrow 7,503]

34 minutes ago, noaano said:

I guess I would choose something like this for this use, it has expandability, swappable/expandable memory, network remote access and a local display for quick look on values:



.....and a ECB that isn't marinised, no IP rating and so guaranteed to go to shit....though maybe you could have data loggers to monitor the data loggers. 

[stief 3,650]

Well, looks like the slamming loads are more FORWARD of what was expected

Quote

You are now sailing multihull angles and speeds, the differences in terms of angles and speeds sailed on this race course by the latest generation foilers will be bigger, what are the key things you are looking for in terms of conditions and preferred angles?
One of the big changes is for these boats to go at multihull speeds very close to the wind. That is a big change. The limitation are the hulls, that was not maybe expected as much and the slamming areas are much further back now. I think there are limitations there. But our real area is downwind, the race is a downwind race. I hear people talking about it being  a reaching race, but for me if you look at the stats, the two southern ocean legs the angles are mostly wider than 100 deg TWA and actually close to 50% VMG downwind. That exclusion zone now, if you say there is no loss in a gybe, your routing would have you doing 1000 gybes between Africa and Australia. That has been our focus, making the boat go fast downwind. The only difference can be the Equator north, that can be 25-30 per cent upwind. But we look at our simulations and we look at weather from 1979 onwards and it does not matter how slow the boat goes upwind, as long as you are go faster downwind then that is the way to go. That has been our big learning from the beginning. That was the learning we used on the last boat and we have pushed it even further this time.

from just before the start (same article that talks about 1hz)

[k-f-u 121]

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...

[Buck Turgidson 77]

very doable if he's got enough box or tube structure. Its a webbing  between hull and deck that takes compression loads but is cut out to save weight. He can either cut plates to attach the capping to the hull or add compression posts directly from deck to hull. 

[yl75 1,027]

What does he says at the end of the sentence "we carry plenty of stuff carbon, etc" "girth" or something ?

[noaano 135]

Just now, jack_sparrow said:

ECB's that aren't marinised are guaranteed to go to shit..though maybe you could have data loggers to monitor the data loggers. 

For one race you can do wonders with spraycoating the electronics though, or put the whole unit inside an enclosure - though then you loose the local display but can access it over network.

Or maybe this is better, waterproof to IP67, -40 to +70°C:

[Buck Turgidson 77]

5 minutes 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...

It's about where you carry the weight. 30kg in the bow is not the same as 30 kg on the centre of gravity. force x distance. 

[stief 3,650]

2 minutes ago, yl75 said:

What does he says at the end of the sentence "we carry plenty of stuff carbon, etc" "girth" or something ?

"02:15 and even girders"

[noaano 135]

6 minutes 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...

If you make structure stronger, it will break at another place. Its all about weight. Repair material is a backup.

[Buck Turgidson 77]

3 minutes ago, yl75 said:

What does he says at the end of the sentence "we carry plenty of stuff carbon, etc" "girth" or something ?

Girder.  https://en.wikipedia.org/wiki/Girder

[BozoC 112]

And while we discuss Alex's repair, JLC is once again at the right place at the right time and the fastest boat of the chasers ..... he is just incredible!

[jack_sparrow 7,503]

29 minutes ago, MastaVonBlasta said:

don't know what they've put into Alex' food bags... If I were him my mood would have been quite a bit lower...

.....OR his mood has risen after getting over the shock of the whole thing.

He is really looking forward to the "fix boat" vid series being wrapped up and the support boat to arrive tomorrow to lift him off and out of there. 

[MastaVonBlasta 108]

I'm guessing what he's showing is a full depth girder made of out of composite sandwich plates.

While the carbon outer shell of the panel is cracked, I wonder if the core (whatever it's made of) has survived undamaged.

Even if he restores the continuity of the panels faces, the core could already be weakened and deformed, and I don't think he'd able to really know without breaking out the panel sections...

 

I know very little about composites, but jeeeeez this doesn't look pretty!

[Miffy 2,125]

Wonder how much upwind work at the start and sailing into the storm contributed to the issues. 

[JonRowe 678]

23 minutes ago, noaano said:

Yes, I don't really know what sort of datalogger they use, but with strain gauges and accelerometers and rate gyros you most definitely are interested in maximum values for the sampling period.

Many "normal" dataloggers certainly do have option for recording this as well.

I guess I would choose something like this for this use, it has expandability, swappable/expandable memory, network remote access and a local display for quick look on values:

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, fibre optics (for stress / strain in the hull) likely use a seperate processor that also feeds into the main navigation network, but for logging purposes I'll bet it is unified as you want to correlate data and two seperate sources and timestamps make that harder.

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 are usually less feature complete than off the shelf equivalents on land, because the market is smaller, so the investment is smaller and features more targeted, I would be surprised if they'd used something like you've linked.

[stief 3,650]

Just now, MastaVonBlasta said:

but jeeeeez this doesn't look pretty!

Guess that's why he slept while the engineers worked on the issue  

[stief 3,650]

2 minutes ago, Miffy said:

Wonder how much upwind work at the start and sailing into the storm contributed to the issues. 

Or slamming on a UFO anywhere . . .

[Buck Turgidson 77]

4 minutes ago, MastaVonBlasta said:

I'm guessing what he's showing is a full depth girder made of out of composite sandwich plates.

While the carbon outer shell of the panel is cracked, I wonder if the core (whatever it's made of) has survived undamaged.

Even if he restores the continuity of the panels faces, the core could already be weakened and deformed, and I don't think he'd able to really know without breaking out the panel sections...

 

I know very little about composites, but jeeeeez this doesn't look pretty!

the core is non structural it will either be foam or most likely air.

[Varan 1,755]

Cannot imagine how horrible it must be to operate a grinder, cutting carbon, in that hot, humid, dark, bouncing environment. Good thing the weather is benign at the moment.

Bet he sleeps at another 6 hours immediately after the repair.

[jackolantern 451]

Jesus. That is a horrendous amount of damage. Looks like he landed just wrong on a wave top between the two cracks which found a weak spot that popped the cap off and pushed the bottom of that longitudinal up to cause the crack. If the damage was enough that he could feel the boat flexing differently then it’s not just a surface crack.

That’s going to be a fucking gnarly repair job. If he pulls it off and finishes it will be up there with some of the mid-race repairs done to the Volvo 70s which had deformation due to slamming. 

Although he’s playing positive I’m falling into the camp of folks who don’t believe that it’ll hold. I think we see him get a “functional” repair together, he starts sending it in a low pressure, then it busts and he either peels off into Cape Town or Hobart when it fails again. 

But he may drop out earlier. Can someone orient me  around where the J3/headstay tack is in this area? I see a hydraulic tack ram nearby but there are lots of those. If this damage is even partially related to his headstay structure then I’m calling the ballgame. 

 

[LeoV 2,195]

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

[Corryvreckan 189]

Looks like Pip crossed the equator ahead of the rest of her group.

[Buck Turgidson 77]

2 minutes ago, LeoV said:

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

yes I laughed but what else would you use? 

[JonRowe 678]

10 minutes ago, Buck Turgidson said:

the core is non structural it will either be foam or most likely air.

These boats don't have core everywhere, they use monolithic carbon for the skin in a lot of places.

[eliboat 250]

9 minutes ago, Buck Turgidson said:

the core is non structural it will either be foam or most likely air.

Core is absolutely structural, and the choice of core makes huge difference on the performance of a given panel.  What your primarily looking for out of a core is shear strength, as that is generally how a panel will fail when the core is not appropriate for the given load scenario.  

[jack_sparrow 7,503]

40 minutes ago, noaano said:

49 minutes ago, MastaVonBlasta said:

I don't know what they've put into Alex' food bags... If I were him my mood would have been quite a bit lower...

It is calles 'Pilot's Salt' in the professional circles....

The packing reads: "Alertness aid," to be taken "to maintain wakefulness" -- but, it continues, "only from time to time" 

So you are saying Alex has a 'blow up girl' on board and is snorting coke off her plastic tits?

Do HB, Mercedes and Nokia know about this shit?

[eliboat 250]

35 minutes 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.

Probably tubes that carry lines aft to the cockpit. 

[JonRowe 678]

16 minutes ago, Miffy said:

Wonder how much upwind work at the start and sailing into the storm contributed to the issues. 

I wonder if there was an undetected pre-existing issue from the keel incident, I feel you know more about boatbuilding than myself, how likely is it that NDT / ultrasound missed a bubble or stress issue in this area when they tested it?

 

4 minutes ago, LeoV said:

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

The wedges or the poles? I think Alex has the er... hindsight, to decide  what repair materials to take  :/

 

30 minutes 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...

They simulate loads and build the boat to withstand those loads, but you don't overbuild the boat for something you don't expect. However you know your modelling is not perfect, that incidents (like hitting UFOs) happen, so you bring materials to reinforce places when breakages happen. If it doesn't break at all its too heavy, and if it breaks its too light. Perfect weight is getting around the world in 1st place with the least amount of breakages

[LeoV 2,195]

Looks like it cracked in  many places all around this structural part and the rest seems fine.
I can see a repair functioning 100% as he has girders :), no really,  I have some experience with it and it is very doable. As long as there is no movement while curing. And you must take your time doing it good.

[Buck Turgidson 77]

3 minutes ago, eliboat said:

Core is absolutely structural, and the choice of core makes huge difference on the performance of a given panel.  What your primarily looking for out of a core is shear strength, as that is generally how a panel will fail when the core is not appropriate for the given load scenario.  

we are talking about the longitudinal webbing down the middle of the boat that is essentially the "core" between hull and deck. It acts as the separator in the I beam design. Given that it is capped it is definitely not a single monolithic piece. 

[LeoV 2,195]

Just now, JonRowe said:

The wedges or the poles?

the wedges but it could be an other material then wood ... who knows...

[k-f-u 121]

31 minutes ago, Buck Turgidson said:

It's about where you carry the weight. 30kg in the bow is not the same as 30 kg on the centre of gravity. force x distance. 

 

30 minutes ago, noaano said:

If you make structure stronger, it will break at another place. Its all about weight. Repair material is a backup.

So that means if his bow structure had been 30 kg (random number I guess) heavier and thus structurally stronger, the boat would have broken elsewhere? 

I guess it's fair to say that the boat was just not built strong enough or AT took it beyond its limits? 

Edit: and also, if he manages a stronger than before repair I assume he can't go at 100% (since the boat would break elsewhere thanks to the heavier bow) 

[JonRowe 678]

Just now, LeoV said:

the wedges but it could be an other material then wood ... who knows...

I mean us mere mortals take wooden bungs for holes, I can believe IMOCAs take wooden wedges for similar reasons 

[Buck Turgidson 77]

7 minutes ago, JonRowe said:

These boats don't have core everywhere, they use monolithic carbon for the skin in a lot of places.

No one is talking about the hull skin. 

[JonRowe 678]

2 minutes ago, Buck Turgidson said:

No one is talking about the hull skin. 

The skin is an example, I am just not assuming there is core in those beams.

[stief 3,650]

back in 2012, the assisted Telefonica team repaired their bow problems in 17 hrs, in worse conditions.

 

[Buck Turgidson 77]

Just now, JonRowe said:

The skin is an example, you don't know there is core there.

what's the purpose of a core in a box beam?

[The Tug 8]

This damage had to have happen'd north of the equator,sinse he came into the south Atlantic it has been a joy ride.Furthermore no repair he can do will bring that frame back to it's original strength let alone where he's planning to go and what he's planning to do.

[MastaVonBlasta 108]

9 minutes ago, eliboat said:

Core is absolutely structural, and the choice of core makes huge difference on the performance of a given panel.  What your primarily looking for out of a core is shear strength, as that is generally how a panel will fail when the core is not appropriate for the given load scenario.  

I would say core would be structural here.

Any compressive load applied to the bow bottom would be carried through the girder web (exactly like a web in I-beam). The carbon skin of the sandwich panel couldn't carry the compressive load, cracked in a brittle failure and the 'cap' bond (capping strip covering the core between carbon skins) and the carbon skins themselves debonded locally.

With a large skin bonded around cracked lines he could probably re-establish a load path, around the cracked skin and then rely on sandwich bond further away.

But to do such repairs when the bits are flexing - must be very difficult!

[jack_sparrow 7,503]

18 minutes ago, LeoV said:

As long as there is no movement while curing. And you must take your time doing it good.

If not then the 2k max warranty written in Afrikaans kicks in.

[Buck Turgidson 77]

2 minutes ago, MastaVonBlasta said:

I would say core would be structural here.

Any compressive load applied to the bow bottom would be carried through the girder web (exactly like a web in I-beam). The carbon skin of the sandwich panel couldn't carry the compressive load, cracked in a brittle failure and the 'cap' bond (capping strip covering the core between carbon skins) and the carbon skins themselves debonded locally.

With a large skin bonded around cracked lines he could probably re-establish a load path, around the cracked skin and then rely on sandwich bond further away.

But to do such repairs when the bits are flexing - must be very difficult!

or he puts compression posts directly between hull and deck. 

[staysail 316]

If he knows anything about structural design and if that lot has failed like that without the boat hitting anything solid Alex will be a very brave man if he sails it hard in the Southern Ocean after performing any kind of repair. Lets wait and see how fast he goes after he has given it all time enogh to fully cure. Hats off to the HB project for allowing that video to be made public.

[JonRowe 678]

6 minutes ago, Buck Turgidson said:

what's the purpose of a core in a box beam?

I will excuse myself from the technical analysis of the repair, my boat building expertise is limited to the gaffa tape / wd 40 diagram, only replace the gaffa tape with wet lay up carbon or epoxy.

 

Feel free to educate me.

[dolphinmaster 83]

45 minutes 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...

Right, why the fuk not put the carried weight of extra into the structure to begin with.

[jack_sparrow 7,503]

6 minutes ago, stief said:

back in 2012, the assisted Telefonica team repaired their bow problems in 17 hrs, in worse conditions.

Stief you are right about their skin delamination and work done to stop bow turning into a wet biscuit and falling off....  HOWEVER I have a niggling thing in my head about some advantage they had???

Just can't put my finger on it. 

[JonRowe 678]

1 minute ago, jack_sparrow said:

Stief you are right about their skin delamination and work done to stop bow turning into a wet biscuit and falling off....  HOWEVER I have a niggling thing in my head about some advantage they had???

Just can't put my finger on it. 

 

The boat was close enough to shore to steal a dinghy?

[LeoV 2,195]

So, I bet team and NA are looking at their files, was it under engineered, were the right products used, and rightly done. So many cracks all around suggest the whole panel moved to much.

Foam density can help if foam and skins are thick;

Sandwich Principle

The sandwich concept is based on two main ideas: increasing the stiffness in bending of a beam or panel and doing so without adding excessive weight. The general term for bending stiffness is flexural rigidity (D), which is the product of the material(s) elastic modulus, and the cross section moment of inertia (I). For a symmetric sandwich beam (both skins have the same thickness and material properties), the formula for flexural rigidity is:

 

With:
E_f = Elastic Modulus of the Facings (Skins)
E_c = Elastic Modulus of the Core
b = Width of the Beam
d = Distance Between Facing Centroids
t = Thickness of a Facing
c = Core Thickness

 

If the skins are relatively thin compared to the core (d/t > 6) and the core material is considerably weaker than the skins (E_f/E_c . td²/c³ > 17), the equation can be reduced to:

 

 

From this equation, it is apparent that the core material does not directly contribute to the stiffness of the panel or beam, (at least in lower density cores) but it's the distance between the skins that is the overwhelming factor. Increasing the "d" variable will have a much greater effect on the flexural rigidity than any other component in the equation, since every other variable has a linear contribution. When dealing with higher density cores (usually > 5 lb/ft 3 ) and thicker skin laminates, the full equation must be used in order to properly predict the stiffness properties. This is due to the high-density core contributing stiffness in the first case, and the thick skins absorbing more shear stress.

https://www.boatdesign.net/articles/foam-core/

[stief 3,650]

2 minutes ago, jack_sparrow said:

Stief you are right about their skin delamination and work done to stop bow turning into a wet biscuit and falling off....  HOWEVER I have a niggling thing in my head about some advantage they had???

Just can't put my finger on it. 

Hehe. That's why I wrote "assisted". Major assistance in tele's case. Team flew in, arranged a charter, and so on. Quite the story.

Was trying to benchmark how long a major carbon job might take.

[C. Spackler 48]

I have to wonder if some engineer forgot to account for the height of foiling bows slamming down into waves at basically a 90 degree angle, while a surfing boat generally hits waves at a less acute angle.  That really looks like engineering failure more than materials or construction failure. 

[BBA 9]

23 minutes ago, Buck Turgidson said:

what's the purpose of a core in a box beam?

Increases buckling limit of the walls when under compression.

[LeoV 2,195]

2 minutes ago, stief said:

Was trying to benchmark how long a major carbon job might take.

This job, onboard, stage were AT is now, rough guess;
1/2 day prep, 2 hours of laminating problem areas, 2 hours laminating  problem areas with girders. Clean up 2 hours
Sleep 6 hours and let all harden.
His team probably will make sure the work process is smooth.

[jack_sparrow 7,503]

16 minutes ago, JonRowe said:

The boat was close enough to shore to steal a dinghy?

Hermits don't have dinghys.

 

[yl75 1,027]

One thing for sure, the boat looks extremely well build (compared to what we had seen from l'Occitane for instance), but obviously on the light side ..

[Raked Aft\\ 111]

is it possible that the design on HB's bow focuses too much on strength and stiffness of longitudinal stringers in lieu of the skin?  

My thought is that given the shock loads,  a more robust hull form and somewhat elastic internal frame system would yield a better all around structure.

 Carbon is certainly a superior material, but it does have it's shortcomings in being inelastic or brittle with high shock loads.

it would be interesting to compare the weight difference in carbon between the skin and stringers in the bow...

 

 

[jack_sparrow 7,503]

1 hour ago, noaano said:

1 hour ago, jack_sparrow said:

ECB's that aren't marinised are guaranteed to go to shit..though maybe you could have data loggers to monitor the data loggers. 

For one race you can do wonders with spraycoating the electronics though, or put the whole unit inside an enclosure - though then you loose the local display but can access it over network.

Or maybe this is better, waterproof to IP67, -40 to +70°C:



Or better still pay an extra $1k for one fit for service. 

[Laurent 1,595]

8 hours ago, DVV said:

That's what I thought. Was this issue the reason for his taking away from Theta, and not following Le Cam? Could this be the reason for the - relative - slowness shown in respect af LinkedOut and Apiva? Isn't it a bit odd that he found out about the issue exactly when the conditions were perfect for the repair?!

 

Alex said earlier in one of his videos that he had a wipe out while sailing close to Theta; he ended up on the other tack, and concluded that it was enough and continued on that tack that was getting him away from the center. (13th of Nov, 12 UTC)

[LeoV 2,195]

I am fan of Dalin, but Ruyant can get the big 3 on his name;
Vendee Skipper section; With one Mini-Transat, one Route du Rum on Class 40 and one Transat AG2R on Figaro, only one victory on IMOCA is necessary for Thomas to become the first sailor to win the three big categories in off-shore racing.

Dalin minitransat was a 2d place... but won Figaro, and Jacques Vabre.

Both very talented and now in almost sisterships having a match race around the globe.

 

[troll99 446]

9 minutes ago, Buck Turgidson said:

or he puts compression posts directly between hull and deck. 

Tripon doesn't need to do that "facepalm"

 

20 minutes ago, yl75 said:

One thing for sure, the boat looks extremely well build (compared to what we had seen from l'Occitane for instance), but obviously on the light side ..

That's funny. I rather take a well-working boat than a pretty look. Similar to women. 

"hint" L'Öccean. 

16 minutes ago, Raked Aft\\ said:

is it possible that the design on HB's bow focuses too much on strength and stiffness of longitudinal stringers in lieu of the skin?  

My thought is that given the shock loads,  a more robust hull form and somewhat elastic internal frame system would yield a better all around structure.

 Carbon is certainly a superior material, but it does have it's shortcomings in being inelastic or brittle with high shock loads.

it would be interesting to compare the weight difference in carbon between the skin and stringers in the bow...

 

 

My opinion is that the empty King's chamber, where Alex operates inside,  contributes to more flex overall. Then the bow part got shit from that eventually. 

Loads come from the middle of the hull where shear is highest then the loads get distributed outwards in the hull. If the middle of the hull was not stiff enough and that is bound to happen. 

 

1 hour 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.

[Snowden 295]

1 hour 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...

if the black box can survive the plane crash, why not make the whole plane out of that stuff? (just teasing)

[C. Spackler 48]

How lame is it that Alex has shut down his hub data at the one moment when it's most interesting?  Answer on a scale of 1-10. 

https://www.alexthomsonracing.com/the-hub/alex/

[Chasm 596]

Lots of distraction with Alex but Pip did indeed beat Arnaud over the Equator.
6 foilers (incl Corum) and 7 conventional boats behind her. Not exactly what I expected from the old Superbigou.

[Miffy 2,125]

I think Alex probably said fuck it and took off the biometric tracking gear. 

[LeoV 2,195]

Nah, he is covered in carbon dust, no connection

[JoeBleaux 45]

1 minute ago, Miffy said:

I think Alex probably said fuck it and took off the biometric tracking gear. 

Don't want to get epoxy all over it. 

[TPG 173]

1 minute ago, Miffy said:

I think Alex probably said fuck it and took off the biometric tracking gear. 

First time I looked at that page

Quote

FACT: On land, Alex has a resting heart rate of just 45 bpm.

That's not particularly interesting or significant?

[ctutmark 235]

Looking at the line tunnel box early in the video before he heads into the den of misery, it seems the bulkhead immediately forward of the damage is the J3 chainplate.  In this pic the J3 furler drum is visible where the lines emerge from the foredeck

[Miffy 2,125]

1 minute ago, ctutmark said:

Looking at the line tunnel box early in the video before he heads into the den of misery, it seems the bulkhead is the J3 chainplate. 

I know all the new imocas are gonna have foils but when they do pull down tests, I still think damn looks good without them. 

[Your Mom 993]

I'm wondering about risk assessment.  What happens if the repair fails catastrophically when he slams into a wave at 32 kts in a low near point nemo?  In all seriousness, would the bow fall off?  Or would the remainder of the structure keep the boat seaworthy enough for him to at least safely reach port?  That damage is all behind the crash bulkhead, so if the hull fractured there, he'd sink within minutes, right?  I'm hoping someone knowledgeable will be able to say a lot more would have to go wrong to get from failure of the repair to hull fracture...  I'd love to see him send it, but I don't want to see him die trying.

[troll99 446]

fuck boats.  says she

A medal for her and Medalliona 

[troll99 446]

1 minute ago, Your Mom said:

I'm wondering about risk assessment.  What happens if the repair fails catastrophically when he slams into a wave at 32 kts in a low near point nemo?  In all seriousness, would the bow fall off?  Or would the remainder of the structure keep the boat seaworthy enough for him to at least safely reach port?  That damage is all behind the crash bulkhead, so if the hull fractured there, he'd sink within minutes, right?  I'm hoping someone knowledgeable will be able to say a lot more would have to go wrong to get from failure of the repair to hull fracture...  I'd love to see him send it, but I don't want to see him die trying.

depends how well the repair is done. If it is well done, it is basically new boat. Simple as it is. 

[Hitchhiker 824]

2 hours ago, stief said:

Finally 4 of the cracks shown. Reassuring that "the boat will be as strong if not stronger than before" Good that he took the time to mark them

 

Unless he has a vacuum pump and bags any other repair technique is likely to be secondary bonding in execution only.  That cannot be considered to be stronger than original unfortunately .

I am glad he is so upbeat and completely confident that he will pull off some type of repair. 

As an aside. I once “repaired” (?) a broken Carbon fiber spinnaker pole with a Fire extinguisher, carbon battens and a banding tool.  Scary as fuck after.  

This damage is next level to the power of 10!

[MastaVonBlasta 108]

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

 

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

[sailer99 42]

3 minutes ago, Your Mom said:

I'm wondering about risk assessment.  What happens if the repair fails catastrophically when he slams into a wave at 32 kts in a low near point nemo?  In all seriousness, would the bow fall off?  Or would the remainder of the structure keep the boat seaworthy enough for him to at least safely reach port?  That damage is all behind the crash bulkhead, so if the hull fractured there, he'd sink within minutes, right?  I'm hoping someone knowledgeable will be able to say a lot more would have to go wrong to get from failure of the repair to hull fracture...  I'd love to see him send it, but I don't want to see him die trying.

The fact that they are consulting with the designers and engineers gives me some confidence. I'd expect them to also install sensors into the repair (the boat seems to have enough tech that they likely accounted for the need to add or replace sensors on route). Regardless of the money involved, no engineer is going to sign off on the boat being good to go unless they have high confidence.

[LeoV 2,195]