AC 36 Foiling Monohulls

Discussion in 'Sailboats' started by OzFred, Sep 13, 2017.

  1. schakel
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    schakel environmental project Msc

    Now this is what I call planning:

    2021 AMERICA'S CUP KEY DATES

    November 30, 2017: AC75 class concepts released to key stakeholders
    January 1, 2018: Entries for challengers open
    March 31, 2018: AC75 class rule published
    June 30, 2018: Entries for Challengers Close
    August 31, 2018: Location of the America's Cup match and the challenger series confirmed; specific race course area confirmed
    December 31, 2018: Late entries Deadline
    March 31, 2019: Boat one can be launched
    Second half of 2019: two America's Cup World Series preliminary events
    February 1, 2020: Boat two can be launched
    2020: three America's Cup World Series preliminary events
    10th-20th December 2020: America's Cup Christmas regatta
    January and February 2021: Challenger series
    March 2021: America's Cup

    I am very glad with the new Defender.
    I remember change of rules with the AC72 to AC45 to AC50's.
    Expensive stuff to build.
     
  2. Dolfiman
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    Dolfiman Senior Member

    As no towing tanks and wind tunnels authorise, I imagine boat one will be based on numerical tools of optimisation and, for the first months of tests, fully instrumented with a lot of sensors and high frequency data acquisition. In order to validate more accurately the VPP tool and optimise boat two design. But timing is short for that plan.
     
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  3. OzFred
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    OzFred Senior Member

    So instead of wind tunnels and tow tanks they'll use the full sized boat on the water.

    They're allowed to change up to 25% of one hull, so maybe they'll continue with one boat for as long as it takes to get it as sorted as they think they can get it, then build the second. That first boat is going to be chopped and changed quite a bit. Likely there will be at least two full crews to sail the boat as much as they possibly can in the time allowed to collect data for the second boat.

    I wonder how they'll measure the 25% given that the length is fixed? Maybe it will be purely lineal, so 5.7m of bow, stern or midships or some combination that sums to 5.7m. Or maybe it will be a volume thing, to allow longitudinal changes (say sections with narrower or wider beam). It seems unlimited changes to rig, sails and foils are OK too.
     
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  4. michaeljc
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    michaeljc Senior Member

    "As no towing tanks and wind tunnels authorised"

    Can someone point me to the reference material where this was stated? I have not seen it . It sounds very odd to me. Why ever not?
     
  5. Dolfiman
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    Dolfiman Senior Member

    It is in 8) COST CONTAINMENT :

    • An ongoing objective has always been in containing costs for teams practically.
    • This Protocol has taken cost containment into account as much as possible including:
    Maximum two hulls for each competitor of which only one can be modified up to 25%
    Incorporation of one- design and / or standard single manufacturer elements Restrictions on materials and construction techniques
    Prohibition of tank testing, wind tunnel testing and similar fluid dynamic testing.
    Meteo ban on gathering weather information outside of a common program for all teams and exisiting public information that is readily available.

    >>> I agree that 25% sounds large (I presume because it is the first boat of a new class) and deserves an exact definition not easy to write if we want to prevent endless interpretations. Does it means boat two with 0% modification ? Not realistic too.
     
  6. michaeljc
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    michaeljc Senior Member

    "Prohibition of tank testing, wind tunnel testing and similar fluid dynamic testing."

    Weird - Firstly, how will they police this? Secondly, the are talking cutting edge 'high tech' . Imagine telling F1 teams that they can not use wind tunnels. I really hope they drop this clause - one reason being that it gives TNZ an advantage. They are specifying the design. On what existing information will they base this design? Much of our existing knowledge has been established through dynamic testing in the past. Lastly, this is not good engineering practice IMO
     
  7. schakel
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    schakel environmental project Msc

    It is stated in the protocol cost containment page 6
    I quote:

    8) COST CONTAINMENT • An ongoing objective has always been in containing costs for teams practically. •
    This Protocol has taken cost containment into account as much as possible including:
    - Maximum two hulls for each competitor of which only one can be modified up to 25% - Incorporation of one- design and / or standard single manufacturer elements -
    Restrictions on materials and construction techniques -
    Prohibition of tank testing, wind tunnel testing and similar fluid dynamic testing. -
    Meteo ban on gathering weather information outside of a common program for all
    teams and exisiting public information that is readily available.


    I couldn't believe it either.
     

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  8. michaeljc
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    michaeljc Senior Member

    "Meteo ban on gathering weather information outside of a common program for all"

    How on earth will they police this?

    I am very proud of our designers and sailors but heck, there are great holes in their protocol model
     
  9. schakel
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    schakel environmental project Msc

    You are right. Talk to Grant Dalton about it. You live nearer to him then I do:)
    grant dalton.jpg
     
  10. Doug Lord
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    Doug Lord Flight Ready

    ==============
    I wonder if large radio controlled test boats would be legal-it wouldn't be "tank testing" and a whole lot could be learned......
     
  11. Dolfiman
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    Dolfiman Senior Member

    Actually, we are not far from a fully controlled and steering of a sailing boat, inc. decision tool when in close competition with another one, that is the problem !
    More than ever, the on-board technologies should be carefully ruled, concerning mechanisms, energy, measured parameters, data communication with ground, data management and decision tool, ... all things that can help humans re. forces, information and decision.
     
  12. Doug Lord
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    Doug Lord Flight Ready

    Dolfiman, what a great article! I'm posting it below as a pdf:
     

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  13. OzFred
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    OzFred Senior Member

    The current Mini 650 foilers have autopilots that can (apparently) work successfully while foiling, so that technology is already here, even if still bleeding edge. F1 has been successfully limiting automation for decades, I can't see why it's a challenge for sailing. It's just a matter of establishing the parameters and enforcing them.

    I think it's easier to fully automate some things and leave others as fully manual. F1 have all sorts of aids feeding information to the driver, but steering, breaking and gear changes are still manual (though pushing a button to change gears when a light comes on isn't that manual).
     
  14. BlueBell
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    BlueBell Ahhhhh...

    OF, I agree with you but a mix is nice.
    To have the auto/manual option.
    Think of auto pilot: great to have, nice to be able to easily overide.
     

  15. Doug Lord
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    Doug Lord Flight Ready

    Option 3 renders by Julian Bethwaite done long ago:

    billoch1.jpg billoch2_jpg_sml.jpg
     
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