The IMOCA 60 Future Gets Clearer

Discussion in 'Sailboats' started by Doug Lord, Dec 12, 2018.

  1. CT249
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    CT249 Senior Member

    Thanks for the info. Where were the non-foilers at the last mark? Are they losing or gaining upwind?
     
  2. philSweet
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    philSweet Senior Member

    They basically held their own upwind. The old boats have a different (more complicated and larger capacity) water ballast system if I recall. Early after the mark rounding there was about 17 knots of wind and several old boats gained a few few miles. But the pack seemed to be even in 12 to 15 knots and the foilers might have a slight advantage under 12 knots.
     
  3. Dolfiman
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    Dolfiman Senior Member

    The first interview of the winner Jérémie and Christopher, not yet translated in En :
    https://www.defi-azimut.net/fr/actualites/news/-toutes-les-victoires-sont-bonnes-a-prendre-
    Yes, the non foilers did great (5th and 6th) in front of some last generation foilers or last refit with foils. They build their brilliant rankings partly at the end of the second leg (the gybes to turn the mark) and also maintain the speed (Apicil) or increase a bit (Banque Pop) during the 3rd upwind leg, they eventually put Inititiatives Cœur /Sam Davis (7th) few minutes behind them.

    11th Hour was less at ease upwind (Beam is only 5,4m so less power) and cannot maintain their 2nd, but brilliant race anyway and they forced Charal to hard sail during the 2 first reaching and downwind legs.

    It is assessed that a complete foils system costs an extra 800 kg (inc. the hull reinforcements), putting the light weight at ~ 8000 kg instead of 7200 kg without. So the the foils should also compensate for that extra weight to be rewarding.
     
  4. CT249
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    CT249 Senior Member

    Very interesting, both of you. Thanks
     
  5. Dolfiman
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    Dolfiman Senior Member

  6. Dolfiman
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    Dolfiman Senior Member

  7. Dolfiman
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    Dolfiman Senior Member

  8. Tiny Turnip
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    Tiny Turnip Senior Member

    I'm curious about the difference in 'attitude' between the IMOCA 60 boats and the AC36 boats when flying. I'd be grateful for explanation both of the different ways the foils are working technically,
    and the reasons why the foils are different. Does it come down to material properties, strength, in the foils, and scaling factor, or something else.
    Thanks.
     
  9. wet feet
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    wet feet Senior Member

    IMOCA Open 60's don't have rudder foils and thus can't foil in the same way as a boat intended to have it's hull clear of the water.
     
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  10. Doug Lord
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    Doug Lord Flight Ready

    Well said, WF! The debate about allowing rudder lifting foils continues and is the only impediment to these boats being full flying foilers. The rule will be changed one day.......
     
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  11. Dolfiman
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    Dolfiman Senior Member

    Hugo Boss, a guided tour by the Boss himself :
     
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  12. Doug Lord
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    Doug Lord Flight Ready

    I wish him luck!
     
  13. Tiny Turnip
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    Tiny Turnip Senior Member

    thanks both. is it possible to summarise the arguments both ways - for and against rudder foils?
     
  14. Dolfiman
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    Dolfiman Senior Member

    Michel Desjoyeaux also advocates for rudder foils in this interview «The new IMOCA are like stools that lack a foot .... » prevented a more natural full flying mode , and he also mentions another inconvenient : the slamming occurrence at high speed on the half rear of the hull bottom, which is flat (quite no rocker there) and not reinforced as it should be now like for the bow zone « What is obvious (and the structural problems of Initiatives Coeur during the Route du Rhum demonstrate this) is that there is more and more effort on the rear part of the hull: before, a monohull slammed on the bow; today, it is at the level of the keel, or behind ! »
    https://voilesetvoiliers.ouest-fran...-un-pied-5b59ac98-d95a-11e9-b412-badb54ee5c05
     
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  15. Doug Lord
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    Doug Lord Flight Ready

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