GC 32 super cat

Discussion in 'Multihulls' started by Doug Lord, Oct 15, 2012.

  1. Doug Lord
    Joined: May 2009
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    Doug Lord Flight Ready

    Gc32

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    Wow, thats great! Same thing happened in the development of the Flying Phantom: as I understand it, Martin Fischers boards were replaced by boards similar to the AC boards and they sailed in the the typical 3 foil configuration with a single main foil and Voila!--they are incredibly fast and foil relatively high.
    Great move on the 32's part-will make a huge difference.
    Thanks for the info....
     
  2. Corley
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    Corley epoxy coated

  3. Doug Lord
    Joined: May 2009
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    Location: Cocoa Beach, Florida

    Doug Lord Flight Ready

  4. Baltic Bandit

    Baltic Bandit Previous Member

    did they watch the same C-Class champs I saw? The foilers, including Cammas, were hardly "stable". Even Cammas struggled with flying in quite a few conditions, and the consensus seemed to be that he won in no small part because of his canting rig, not his foils.
     
  5. mrmac
    Joined: Dec 2011
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    mrmac Junior Member

    Depends what you term as stable, but from the many times i have viewed the Groupama C Class i have been very impressed at the inherent stability afforded by the foils.

    If you are looking for a ride that is comparable to a super tanker then I think you are looking in the wrong place.

    The Groupama domination of the C class event was a combination of factors, but the foil stability was a major factor. It allowed the team to be conservative when others were taking massive risks to maintain similar average speeds.

    Have a look at the Flying Phantom Video on facebook https://www.facebook.com/photo.php?v=10151963577204287 this is using the exact foil from the C Class.... looks stable enough to me!
     
  6. Baltic Bandit

    Baltic Bandit Previous Member

    GroupAma was able to be conservative because they mostly rounded the weather mark first. One of the races in which one of the Hydros boats took them up at the start, essentially closing the door on them was very very instructive.

    The Hydros boat was sailing in point mode on GroupAma's lee bow off the start,, and yet within 100 meters GroupAma had CLIMBED OUT of the dirt from Hydros. And that is attributable almost exclusively to the canting wing.

    the foils were fairly stable - but Hydros showed a lot more speed off the wind than GroupAma. Dramatically more. If you look at the onboard video of GroupAma before the regattae, they showed how much very very active wing trim is required to stay on the foils. This is not the skillset of even your average cat sailor. 15-30 degree trim changes 2-3 times per second.
     
  7. mrmac
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    mrmac Junior Member

    Well, I guess you have a different view of the event than everyone I know, including the two teams you mentioned above.... Both of which i know personally very well and both are very happy to say that the foil stability of Groupama was a major factor in their success. Sure the Hydros boats had potential to go fast, but they couldn't do it for long enough to make any impact on the average speed obtained by Groupama.

    I was on the water for the race start that you mentioned, it was impressive to see how Groupama was able to lift off the hydros boat, but without a good foil package it would have been impossible. You are picking parts of a package that suit your argument and ignoring the rest. The performance was a result of the whole thing working well.

    Anyhow, we are really happy with the stability and performance both on the C class and the flying phantom, which is very easy to sail.
     
  8. Baltic Bandit

    Baltic Bandit Previous Member

    you're a lucky dog if you got to be at that event!!

    But there's a diff of "stability" with a pilot like cammas and the guys buying the 32s
     
  9. mrmac
    Joined: Dec 2011
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    mrmac Junior Member

    Not at all, the stability must be inherent to the foil/platform/rig and this was very easy to observe on the groupama boat, and also the flyiing phantom. The GC32 new foils are designed to be even more stable than the smaller boats.
     
  10. Doug Lord
    Joined: May 2009
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    Doug Lord Flight Ready

    The foiling stablity of Groupama was superb because they used foils much closer to the "up-tip" foil pioneered on TNZ. The Flying Phantom uses a refined version the same foils and is very stable as well as being the first production foiler to result from the refinement of the TNZ system.
    The GC32 will be the second production foiler resulting from refined versions of the breakthru 3 foil system and hybrid main foil used in the AC.
    Very exciting stuff with two manufacturers putting their money where their mouth is with very stable, very fast catamaran foilers!

    http://www.catsailingnews.com/2013/11/fine-tuning-flying-phantom-at-29knots.html#more

    This video was published on May 25th and there will be a newer one shortly. Top speed then was 26.4 and now up to 29 and very stable:
    http://www.youtube.com/watch?v=5doBIv3TVbA&feature=player_embedded
     
  11. Baltic Bandit

    Baltic Bandit Previous Member

    MrMac - if the platform was so stable, why do they have to trim so aggressively when foiling in comparison to when not?

    Doug - if the "v" was so "stable" - why then did someone like Nathan Outeridge have such difficulty keeping Team Artemis flying? Why did it take OTUSA a good way's into the finals before they had foiling gybes locked down?
     
  12. mrmac
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    mrmac Junior Member

    The rate of trim is normal for a boat travelling at that boat speed, if you look at the Phantom videos you can see that the trim is not any more than normal. in fact its less to my eye.

    As for the Artemis issue of stability, they were trying to make a very quick solution very quickly. So they ran a straighter L shape foil which is quicker but less stable, it took Oracle and ETNZ quite some time and a lot of constant effort to make this foil shape stable in a race mode. There is a price to pay in terms of stability if you really want the last few % in speed.
     
  13. Doug Lord
    Joined: May 2009
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    Doug Lord Flight Ready

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  14. Baltic Bandit

    Baltic Bandit Previous Member

    "uptip" implies that just the tip is raised up. These are dihedral or "J" boards with a convex dihedral angle. The difference is important because just an "uptip" like Boeing wingtips -provide some stability and tip vortex reduction

    But a dihedral that relies on spanwise flow to attenuate lift is a very different structure.
     

  15. Corley
    Joined: Oct 2009
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    Location: Melbourne, Australia

    Corley epoxy coated

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