34th America's Cup: multihulls!

Discussion in 'Multihulls' started by Doug Lord, Sep 13, 2010.

  1. Doug Lord
    Joined: May 2009
    Posts: 16,679
    Likes: 348, Points: 93, Legacy Rep: 1362
    Location: Cocoa, Florida

    Doug Lord Flight Ready

    34th AC


    Designing the hulls with low buoyancy was not a design error. It was intentional because they were relying on the foils to prevent a pitch pole-see the quote below. I think it is an excellent design, particularly after they solve the control issue. The foils are powerful enough to have prevented a pitchpole if the control system had worked.

    =========================
     
  2. Stephen Ditmore
    Joined: Jun 2001
    Posts: 1,398
    Likes: 45, Points: 58, Legacy Rep: 699
    Location: Smithtown, New York, USA

    Stephen Ditmore Senior Member

    Since I agree with these statements I'm not sure where you think we differ. My concern is that the boat that wins at the end of the day will not, in my opinion, be as usefully evolved as it would have been had the rules been more open. Doesn't that just follow logically from:
    ...?
     
  3. Stephen Ditmore
    Joined: Jun 2001
    Posts: 1,398
    Likes: 45, Points: 58, Legacy Rep: 699
    Location: Smithtown, New York, USA

    Stephen Ditmore Senior Member

    It can be both intentional and a mistake. The TNZ design team concluded the risk was greater than the payoff according to the interview with Verdier I cited previously. One team will prove right and the other will prove mistaken.
     
  4. SteveMellet
    Joined: Sep 2009
    Posts: 196
    Likes: 7, Points: 0, Legacy Rep: 88
    Location: South Africa

    SteveMellet Senior Member

    Hi Stephen,
    I would only disagree with you that a rule change is needed.
    I feel that the team that best exploits the rules without being caught out and designs the best boat will probably win, which is pretty much how the AC has always worked, regardless of the type of boat involved.
    I kind of enjoy the fact that the rulemakers probably thought they had written foiling out of the event, and the engineers and designers have shown them that it is still possible without advanced control mechanisms or wands. I see this trickling down to beachcats as it is simpler, perhaps the next A-class worlds will see a foiling wing-sailed boat, and the LAC is gong to be very interesting indeed.

    The best boat on paper might be the one designed to always be foiling and have no reserve bouyancy in the bows as it's not needed (on paper).. But the racing happens on water, not on paper. I'd want a plan B for the bearaway, these boats are going to stuff bows in whether they foil or not.
     
  5. Doug Lord
    Joined: May 2009
    Posts: 16,679
    Likes: 348, Points: 93, Legacy Rep: 1362
    Location: Cocoa, Florida

    Doug Lord Flight Ready

    ====================
    Steve, thats not the case: if the foil system works it will prevent a pitchpole.
    I'd hate to carry all that extra hull weight around in case the foil system didn't work. Once they sort the foil control problem they have very fast boat.
     
  6. HASYB
    Joined: Jun 2011
    Posts: 310
    Likes: 16, Points: 18, Legacy Rep: 143
    Location: The Netherlands

    HASYB Senior Member

    I think its a rule error even more.
    If the rules were designed against foiling, the rule makers apparently didn't understand enough of the kind boat they were designing.
    A boat that is only be able to cope with safely bearing off when its foiling!!??
    Which is what the rules suppose to prevent??
     
  7. cavalier mk2
    Joined: Mar 2010
    Posts: 2,151
    Likes: 65, Points: 48, Legacy Rep: 214
    Location: Pacific NW North America

    cavalier mk2 Senior Member

    Maybe Oracle should put a pod up in the bows to prevent unintentional crash dives.....cockpit forward might start a new trend. If they have someone steering and other crew controlling the foils crew error or synchronization could be a contributing factor, too many cooks churning the brine etc...
     
  8. SteveMellet
    Joined: Sep 2009
    Posts: 196
    Likes: 7, Points: 0, Legacy Rep: 88
    Location: South Africa

    SteveMellet Senior Member

    "Steve, thats not the case: if the foil system works it will prevent a pitchpole.
    I'd hate to carry all that extra hull weight around in case the foil system didn't work. Once they sort the foil control problem they have very fast boat."

    Doug, on paper, you might have a point.
    The real world tests theories with a fair amount of consistency.
     
  9. petereng
    Joined: Jan 2008
    Posts: 581
    Likes: 22, Points: 28, Legacy Rep: 252
    Location: Gold Coast Australia

    petereng Senior Member

    Re Rules: The original AC72 draft rules allowed the daggerboard to have 2 axis of motion and the rudder two axis. (from memory). This allowed the daggerboard to be pitched and gybed and the rudder to be steered and pitched. (By the way the original sailing boat mass was 8.5 tonnes and then it dropped to 7.5 tonnes) I was in an AC technical meeting in Auckland early 2011 and the discussion with most people was how much weight they were going to take off the hulls. Which was 2 or 3 tonnes. There was no discussion about foiling at the time. But after that technical meeting something changed, obviously designers expanded their thinking to foiling and then Rule version 1.0 came out and the multiaxis was cut to one axis. So then it became a clever designers world vs a world in which we could design with good control if we were to foil. I'm all for making things simple. If we are to foil let us have flaps and slats and whatever we need to control flight. Why make it hard? But the rules are now set and there is a precedence (set by the Int jury on TMZ boards) that the written word is the rule vs the perceived intent of the rule so the rule words are now set in stone. Unless the defender and the challengers agree to change. There is now a large vested interest in the rules, boats and timelines and they are unlikely to be changed. Anyone who flips a boat now runs the risk of not having a boat or a back up boat for the LV. Either by lack of time or lack of money. I think this is a wake up call and the conservative interests in all projects will kick in. Cheers Peter S
     
  10. Doug Lord
    Joined: May 2009
    Posts: 16,679
    Likes: 348, Points: 93, Legacy Rep: 1362
    Location: Cocoa, Florida

    Doug Lord Flight Ready

    AC 34 on Foils!

    ==============
    You're absolutely right and you can bet the Oracle team knows that. No way they would have made that turn and gotten up on foils in those conditions if they didn't believe in the system. The fact that the system screwed up is unfortunate but now they'll figure it out. After all, it was a test......
     
  11. Doug Lord
    Joined: May 2009
    Posts: 16,679
    Likes: 348, Points: 93, Legacy Rep: 1362
    Location: Cocoa, Florida

    Doug Lord Flight Ready

    34th AC on Foils!

    =================
    I don't know ,Peter. I think in the long run this will provide smaller boats with simpler ways to foil. I think Oracles system is excellent-they just had a problem. But a manual altitude control system is going to require lots of testing and crew experience to get right -but I believe they can do it. And TNZ's fantastic surface piercing foil(with manual assist-setting for conditions) is simply brilliant but if Oracle works out the bugs theres may be faster. Damn cool stuff and lots to learn. As a foiling freak this is like a dream come true: a couple of billionaires funding foil research to make it simpler and more reliable-how cool is that?!
     
  12. oldsailor7
    Joined: May 2008
    Posts: 2,097
    Likes: 41, Points: 48, Legacy Rep: 436
    Location: Sydney Australia

    oldsailor7 Senior Member

    Cool indeed. :cool:
     
  13. Stephen Ditmore
    Joined: Jun 2001
    Posts: 1,398
    Likes: 45, Points: 58, Legacy Rep: 699
    Location: Smithtown, New York, USA

    Stephen Ditmore Senior Member

  14. HASYB
    Joined: Jun 2011
    Posts: 310
    Likes: 16, Points: 18, Legacy Rep: 143
    Location: The Netherlands

    HASYB Senior Member

    Peter, Thanks for the info, really appreciated.
    I hope your you are right about the wake up call.
    Like you say: "Why make it hard."
     

  15. Doug Lord
    Joined: May 2009
    Posts: 16,679
    Likes: 348, Points: 93, Legacy Rep: 1362
    Location: Cocoa, Florida

    Doug Lord Flight Ready

Loading...
Forum posts represent the experience, opinion, and view of individual users. Boat Design Net does not necessarily endorse nor share the view of each individual post.
When making potentially dangerous or financial decisions, always employ and consult appropriate professionals. Your circumstances or experience may be different.