hiroller

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About hiroller

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  1. hiroller

    what is it?

    Not quite sure about that. There is a double bed in the middle of the tramp!
  2. hiroller

    Eds SC-33 Anarchy 3

    What you really need is another SC33 in your fleet to race against. Makes lots of handicap issues go away.
  3. hiroller

    Why was TNZ faster ?

    A bigger righting moment for these boats is the windward rudder The Teams were allowed 3 degrees of rudder rake while sailing So the windward rudder is raked to dig in and provide righting moment. Much more that boat weight. Some teams increased this by slackening the lowers which allowed the boat to wrack. The windward hull would twist forward increasing the amount the windward rudder digs in. I think Oracle started this after using it to great effect in the last cup. By the final ETNZ were also wracking. A major reason that ETNZ crashed was the windward rudder came out of the water causing the boat to lose grip.
  4. hiroller

    Why was TNZ faster ?

    I don't think you will find them de-powering downwind. Have a look at the heavy races upwind. I was told by someone who knows.
  5. hiroller

    Why was TNZ faster ?

    Taking the concept of dreaming the ultimate solution as applied to foils (throwing the ball as far as you can). If you are allowed 4 foils (or 2 sets), the obvious solution is one light wind set and one high wind set that you then need to manage when to choose between set. The ultimate solution would be to have one set of foils that worked in all conditions. While ETNZ didn't achieve this, they got closer than the others. You are allowed to change 10% of foils as often as you want. By having the tip horizontal, you enable the most efficent use of that 10% to vary the foil length to suit the weather. By making the vertical part of the foil longer, you get a bigger 10% to play with. ETNZ were much more creative with the foils to get close to the ultimate solution.
  6. hiroller

    Why was TNZ faster ?

    There was obviously a trade off between being fast to the 1st mark and good upwind speed and speed through tacks and gybes. Some boats tried asymmetric foils (fast port foil / stable starboard foil). ETNZ obviously were comfortable being faster upwind and through manoeuvres. To beat ETNZ meant sailing close to perfect race and hoping ETNZ made enough mistakes. BAR, Artemis and Oracle each did once in the finals. Based on the results, you would imagine that Artemis would have gone close to beating Oracle also. It would be interesting to think of other LV finalists that might have beaten the defender. OneAustralia would have beaten Dennis in 95. The Kiwis probably could have beaten Kookaburra in 87. Really needs another thread.
  7. hiroller

    Why was TNZ faster ?

    Would a boat that weighs 100kg more really have much difference in righting moment? The righting moment of a reversed main would be in the order of tonnes. The maximum combined crew weight is 525kgs. The fact that OTUSA had a bulked up skipper that meant having to have smaller grinders is a more significant factor. Outerridge lost over 10kg to allow bigger grinders. Spithill didn't. ETNZ had access to proprietary carbon mast technology that meant they could have gone even lighter, The other teams wanted to raise the minimum weight but ETNZ refused and it needed unanimous vote to pass. ETNZ only used 2 accumulators not the 3 allowed as they could generate enough "oil" as they were sailing resulting in a further weight saving. Lighter means smaller foils. Smaller foils means faster boat. Lighter boat means faster accelleation. The kink in the foil meant the tip was horizontal, this meant that that swapping out tips allowed more range out each set of foils. Ashby wanted a wing that could be trimmed like an A-Class main, where easing the sheet dumps the leech rather than moving the sail like a barn door. He imagined it, the ETNZ tech team designed it an built it. They wanted a automated ride height, They developed a software packet that calculated and displayed the optimum. ETNZ then built a system that enabled the crew to follow that display. This allowed better stability control which allowed faster, less stable, foils. Old fashion grinders were less windage than cyclors if they stayed on their knees but were more windage when they stood up, which they had to, to match the manoeuvres that ETNZ were pulling off. In 2013, Oracle were able to duplicate the J-Foils and analyse and break down Dean Barkers starting routine. This time ETNZ only showed enough speed to win and didn't engage in starts knowing they had the speed to win. Saving starting smarts and speed advantage for the final.
  8. hiroller

    Why was TNZ faster ?

    The righting moment due to weight of the boat was irrelevant as the all teams were inverting the top of the wing to create positive righting moment.
  9. hiroller

    Live Racing Thread

    A major reason their was no passing today was that the breeze shifted right after course was set meaning that one leg was heavily favoured (S upwind / P downwind). This results in less tacks and gybed and less opportunities for picking shifts. Of more surprise was how quick the races were. They are meant to be 22mins but were only 18min. Why do ETNZ with one Australian get called ETNZ-AUS and OR who have sailed at times with 5 Australians on board aren't called OR-AUS? I also wonder if Sir Russell knows that his staff can't spell his name correctly?
  10. hiroller

    Team NZ

    Here are Bora Gulari's thoughts on the fleet: http://www.sailingscuttlebutt.com/2017/05/15/forming-americas-cup-form-guide/
  11. hiroller

    Team NZ

    Who said moving wing? Most fighter aircraft have stabilators: https://en.wikipedia.org/wiki/Stabilator The F-22 has been delayed for years. Would have been quicker with pedals.
  12. hiroller

    Team NZ

    There are plenty of performance aircraft that use the whole control surface rather than just a flap. Here is the F22, apparently the latest and greatest. You should call them up and tell them they got it wrong.
  13. hiroller

    Team NZ

    Some of the ETNZ design thinking is mentioned in this article with Bernaconi: www.sail-world.com/153122 ETNZ's use of articulated rudders on their AC45S with a 1.5m extension gave them a boat with the same geometry as the AC50. Seems like a neat workaround to the limit on AC50 time on water restrictions. The foils swap between boats, as proven with the use of an old foil when a new one broke on the AC50. I don't think they will be much behind the other teams due to lack of time on the AC50. The other factor worth noting is whether the wind conditions in AKL were closer to Cup conditions than the current stringer breezes in BDA. Meantime, teams all monitor each other closely. They will all have radar speed detectors or equivalent. When asked if they had been watching the YouTube videos of the sailing, Bernasconi said relied they did their own recon. The teams will all know who is fast and stable. Fast will be king but this time the boat who can stay on foils the whole race will win. Artemis have looked fast but good crew work has enabled them to stay on foils longer and they passed boats in the practise races when the opposition dropped off their foils. ETNZ have by far the least match racing experience of the teams on the boat but it may not be a factor if you can't stay on your foils.
  14. hiroller

    Artemis?

    According to the brother of a current AC sailor (today), there are real concerns about: 1) wearing inflatable life vests and getting stuck under the boat. 2) the 2 minute limit of air. Of interest is that a number of current skiff sailors in 18's and 16's on Sydney Harbour don't like wearing life vests as they prevent you from being able to swim out from under the rig in the event of a capsize to windward.