Gitana 17-100' Trimaran Foiler-Launch 7/17/17

Discussion in 'Multihulls' started by Doug Lord, Jul 13, 2017.

  1. Doug Lord
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    Doug Lord Flight Ready

    Gitana 17 main foil w/ flap:

    Gitana 17 main foil.jpg
     
  2. Doug Lord
    Joined: May 2009
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    Doug Lord Flight Ready

    Interview with Cyril Dardashti, Director of the Gitana Team:

    https://www.ouest-france.fr/route-d...-noeuds-quand-le-flotteur-s-est-brise-6097475

    machine translation:
    Route du Rhum. "We were at more than 40 knots when the float broke"

    24 hours after the start of the Route du Rhum, while he was leading Sébastien Josse saw the right float of his Maxi trimaran Edmond de Rothschild explode into pieces. Three weeks later, the reasons for this failure are not yet fully defined. But for Cyril Dardashti, Director of the Gitana Team, two factors explain already the context: the high speed and the height of the waves.

    Do you now know what happened at the time when the starboard float of the Edmond de Rothschild maxi broke?

    No, not quite yet, because we just collect all the data of the boat to analyze, because it doesn't help to make plans on the comet as long as we can't control everything. What is known is that there are a lot of sea, and we would very quickly, both of which are not ideal to keep our integrated boats...

    Is that what you mean by "go fast"?

    We were above 40 knots, it déboitait not bad indeed... We weren't on a conservative mode, but rather on a mode 'attack', because we, in any case, asked was already quite the platform and we knew that in the heavy seas, it was pretty good. Then navigate through 4 m waves at 40 knots, we had never done, because we never had the conditions for that so far. And we realize that it is not passed. Explanations, expected yet, and let's get them.

    Was Sébastien Josse over-revving?

    No, he had to quickly go to the South and more we were going fast, better we wore behind. And besides, we had already dug a little gap, as it was already nearly 40 miles ahead of the longitudinal part, on Macif. It was already substantial and it allowed to build something.

    What was surprising is that it is the float in the wind that blew...

    Yes, but it's because this float here touched the water, anyway. With Max Edmond de Rothschild, we're in a mode of flying, even in the high sea where you can also do interesting things, obviously with a platform a little more flat. And, of course, in those circumstances we also seeks the float in the wind. Even if one has coefficients of relatively high material strength, because a fairly robust boat had been built, in any case known for that, well we realize that this is not enough.

    Also going that we learn to manage these boats. When you do a crash test for a car and we send it on a wall at 60 mph, the car, no matter what it is folded. And it's the same for boats given the speeds which we sail these boats. Therefore, we learn to lift the foot at the time where it's needed.

    In summary, the ultimate are not yet suitable to darken at 40 knots in in more than 4 m from hollow...

    I don't want to anticipate, but anyway it's always a matter of compromise. There are two solutions: where you want it and you build the boat accordingly so that it holds, and in the light airs, you stay stuck to the track up to 15-16 knots or more. Or then you lighter, and you accept to have to slow down.

    Say your architect on this?

    Talk with them (the firm Verdier) to see if you did forget something in sizing. And from there, there are two possible conclusions: If you have forgotten something will be strengthened where there is need, and if you forgot the case reverse, it will adapt our behavior accordingly. I have not discussed with our neighbours to Banque Populaire to know where came their worries, this is a conversation that we have probably as there are to understand all what it is before the jump to conclusions.

    There were not too many voices to criticize the reliability you boats...

    Where I'm happy, it's that the general discourse still been quite measured. I think people understood that it happened in another era, which is that of flying boats. And that this does not happen overnight. One is fortunate to have partners like Benjamin and Ariane de Rothschild, who support us and follow us at bottom on these projects here, which make us do colossal leaps in technology, but which cannot be done without incident. You just have to see the start of the Route du Rhum and the incredible spectacle of these final... it was the star wars... I'm going above, I'll pass below, I pass in flying mode I regulates... The route between Grouin and Fréhel finished in 34 minutes, it was amazing!

    We quickly saw the potential of your boat, during the first 36 hours...

    Yes, but that, we, we didn't had many doubts. I think we were, without having the melon, the boat that was most feared... Already at Port-la-Forêt, in the training, they showed a great potential. The evidence, even if Seb lost command, a moment in the Sept-îles, it resumed it at Ouessant.

    What do do you as a site on the boat in the coming months?

    The boat went into our shed in Lorient. It is doing a check of the platform, not to check if we're not back on a base too solicited. We're preparing the bow of the float broken, so that they can take a new part of bow built at Multiplast. In so doing, it is likely that it reinforces it also... Same as the other float also.

    How long will this take?

    This is long... Let's say we should return the boat to the water end of April. But it's often the price of a good winter project...

    At the financial level, it must be expensive no?

    UH... Yes, this story we is quite expensive actually... We again a bow of 9 to 10 m long, it is almost equivalent to a boat... But compared to what we see our neighbours (Banque Populaire), it is little. And even among Macif, with a foil and rudder again, plus the rest of their repair work... It is almost better off from this point of view here... Not at the level of results, on the other hand...

    It is possible that you put your experiences in common with other ultimate teams?

    Yes, I think that we are going to share a bit. What is interesting is to know how they broke. After one is not obliged to share all our data, either. And above all, addressing, in terms of security, how you look at more...

    What you mean?

    Casually, when you see the State of Banque Populaire after 10 days, we say we have to think about security if it is around the planet... Imagine the ship, returned in the same way, in the deep South, with a man on board... it would go through a few phases of stress.

    The ultimate World Tour, in 2019, happens - it too early? Should it be postponed?

    Honestly, the question arises. That said I am not able to answer today. It is a reflection that there we lead all. It also we have all the elements, to make a choice. What is clear, is that the decision can be ripened. Do not say: that was expected in 2019, and don't move... We can't say: Banzai, let's go, the flower to the rifle, without further explanation on all break and damage each. Because it would be a folly to send guys around the planet without having answers to these questions. Because in the race, it is very different from in record mode. Record, we adapt to the conditions. In race mode, it also fits, but is also interested in other competitors to stay in the game. And it's often a little push to the crime. And is proof of the Route du Rhum. But this round the world solo in ultimate is the Holy Grail. This will be the most beautiful race in the world, I am sure. Today, you cannot do better. But we must do it in a smart and safe way.

    How?

    With the certainty that when any problem at sea, we can recover the snowmen. For me, it's essential. If, in case of capsize, we could say that it is easy to cut the rig and waiting for help inside... but this isn't the case. On a final you can't cut a rigging alone under water, the mast so just type the central hull, floats, it destroys everything... It means to find solutions so that, on a Tour of the world, there are, within three days at sea, a ship able to rescue sailors, if needed. It will take positions around Antarctica, two or three ships of trade, or Navy, or other, to intervene.

    This is not a thin folder that...

    No, indeed, it's a complicated topic but important. Anyway, it would happen to us a thing, you reprocherait us. There are risks, we know, anyway when we leave in the deep South, we know that. On the other hand, when we identify these risks and these dangers and we send guys to fail, it is not reasonable.

    Destroy the boat, ok, this is a topic, and the insurance problem will also arise. Do we ensure our boats tomorrow? I'm not sure. But send a guy saying that there is a chance that he's there, I don't want to.

    People's Bank out, the new Sodebo, not yet released on site, when you know the time it takes to make such a machine... reliable winter 2019 happens too fast not? In addition Idec has not confirmed he would come... There may not be many people on this Brest Oceans...

    It's safe for an ordeal like that... I don't say he should wait until everyone is ready, if not, imagine that we also we break something this year... we'll not get more wait and repel. This is why I do not get me. He need to take this decision, together, a good family man, as they say. With, as I said, a safety requirement.

    You are part of the class ultimate 32/23 Finally?

    No... not at the moment. We're very close, we trade a lot, and I'm sure we'll find our common ground. They are constructive, open, and we also... it crashes just on small issues (slavery). We have a little bit in advance in some areas, especially when we put the finger on the reliability of the machines. We already had experience with the MOD70 flying Edmond de Rothschild, and we had already identified a number of issues.

    And Sébastien Josse, what will do during these months of work?

    He will follow the construction site, and help analyze the data. And then it will also train on our GC32, and continue his learning of the ship flying on our Flight Simulator that allows us to test the configurations of veil of appendages.

    As a simulator for pilot aircraft?

    Yes exactly. This is a simulator that had been developed by team New Zealand to allow Peter Burling, their skipper, to familiarize themselves with the flight on the America's Cup. We did the same, and it's really good.

    For the program this year, and as the Lorient-Bermuda - Lorient is postponed, there is not a lot of upcoming races...

    Actually, it's a bit foggy. We should know more within 15 days. This time, it is true that there is not much. One can imagine many things... If there is not around the world, we can consider the Transat Jacques Vabre, or leave in a campaign of record, crew or solitaire... Or Finally, circumnavigate the ultimate world, even without all the actors. We'll soon know.
     
    Last edited: Nov 30, 2018
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  3. Dolfiman
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    Dolfiman Senior Member

    Thanks Doug, very interesting interview. It seems that a flying mode with then a more flat platform put the windward float closer to the sea surface, and in a beam reaching with 4m waves, a lot of slamming, some violent, can occurred. It is also the Michel Desjoyaux analysis.
    On a float with a fore part of about 10 m in cantilever and related vibration modes, it is a load case that may be was under estimated, which can lead to either a failure to max effort or a failure to repeatation of efforts.
     
  4. Doug Lord
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    Doug Lord Flight Ready

    Gitana 17's bow section found- should help find out what actually happened:

    Gitanas bow section found--2.jpg

    Gitana bow section found-12-6-18.jpg
     
  5. Dolfiman
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    Location: NICE (France)

    Dolfiman Senior Member

    Thanks Doug, Here are some other pictures where the failed section is more visible. The float was found on a Cornwall beach !! more than 300 Miles North of the loss location :
    Le flotteur arraché du maxi-trimaran Edmond de Rothschild retrouvé sur une plage anglaise http://sport24.lefigaro.fr/voile/route-du-rhum/actualites/le-flotteur-casse-d-edmond-de-rothschild-retrouve-sur-une-plage-anglaise-936384
    Monday 3rd of December in Lorient was held a debriefing meeting of the Ultims skippers, where they told to each other their misfortunes, and are ready to open their books to solve the structural problems and increase the safety. A decision is expected by mid-January to maintain end of 2019 or to delay the Brest Oceans round solo race.
    Les marins des Ultimes ont tout mis sur la table après les graves avaries de la Route du rhum http://sport24.lefigaro.fr/voile/route-du-rhum/actualites/les-marins-des-ultimes-ont-tout-mis-sur-la-table-apres-les-avaries-de-la-route-du-rhum-936099
     
  6. Doug Lord
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    Doug Lord Flight Ready

    Thanks....
     
  7. wet feet
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    wet feet Senior Member

    I find it a really positive sign that they are sharing experiences with a view to making things better in the future.The priority has to be going to sea in boats that will get to their destination and the extraction of speed will be on top of a safe platform.It would be valuable if they would publish the (perhaps edited) conclusions to enlighten those of us who are interested in boats that push the boundaries.
     
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  8. Doug Lord
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    Doug Lord Flight Ready

    Good post wet feet. The revolutionary foil system used by Gitana 17, Macif and Banque Pop seems to me to have proved significantly faster than the engineers had thought was possible, particularly, the performance the foil system allows in big waves/chop. They're really on to something- now they have to figure out how to engineer the boat for the foil system-if it's even possible, which I think it probably is.
    A small fullsize tri using this same foil system will be a simply spectacular multihull!

    Gitana 17--picture by Yann Riou :
    Gitana 17 from Voile mag.jpeg


    An exact scale model of a 19.5' foiler tri using the same basic foil system as Gitana 17(or Macif, Maserati and Banque Pop)
    -picture by Dan Burke
    MPX_Fire Arrow-3D SAILING-7-24-14 009 (2).JPG
     
    Last edited: Dec 8, 2018

  9. Doug Lord
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    Doug Lord Flight Ready

    Some great shots of Gitana 17 under way:
     
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