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      Abbreviated rules   07/28/2017

      Underdawg did an excellent job of explaining the rules.  Here's the simplified version: Don't insinuate Pedo.  Warning and or timeout for a first offense.  PermaFlick for any subsequent offenses Don't out members.  See above for penalties.  Caveat:  if you have ever used your own real name or personal information here on the forums since, like, ever - it doesn't count and you are fair game. If you see spam posts, report it to the mods.  We do not hang out in every thread 24/7 If you see any of the above, report it to the mods by hitting the Report button in the offending post.   We do not take action for foul language, off-subject content, or abusive behavior unless it escalates to persistent stalking.  There may be times that we might warn someone or flick someone for something particularly egregious.  There is no standard, we will know it when we see it.  If you continually report things that do not fall into rules #1 or 2 above, you may very well get a timeout yourself for annoying the Mods with repeated whining.  Use your best judgement. Warnings, timeouts, suspensions and flicks are arbitrary and capricious.  Deal with it.  Welcome to anarchy.   If you are a newbie, there are unwritten rules to adhere to.  They will be explained to you soon enough.  
pacice

Foiling Monohull - what would it look like?

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7 hours ago, kiwi777 said:

by the way the designer of hugo boss is Guillaume Verdier who is the top designer at ETNZ who designed our winning foils and now is the principal lead for our 2021 campaign and is leading setting the design rules. Advantage ETNZ I think.

Up to now:

Big point for TNZ as a team, big loss for P$B, big loss for TNZ as a defender willing to make a successful event. Who will be able to afford 2 of these boats + crew + transport + base + research + spare parts ?

Now:

In order to win as the defender, TNZ needs to get china

In order to win as the challenger, P$B needs to be able to outspend TNZ, and he may already be the big winner here.

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9 hours ago, Tornado-Cat said:

That is true for IMOCAs. As you say AC75 will have new T rudders, but foils will also be different. I am very interested to know how they will fare, even though I am afraid it is a very complicated and expensive way to copy a bad multi. But they had to race a mono, so it is quite a creative one.

Well guys, have a look at the kiting formula race board vs a foiling race board. If your talking upwind, the foil is super efficient, higher speeds with tighter angles. More difference here than downwind. 

 

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On 25/11/2017 at 4:09 AM, The Main Man said:

I'm with you. Let's just say it, it looks f*cking stupid.

Canada's Cup went back to 8 meter boats (granted  they are now talking Melges because they are poor with clubhouse reno costs)   so why not go back to J's ?    it brings back majesty and purpose and ocean sailing and deletes  stupid non boats  with zero go forward value to the sport.    There are no builders using  cat A/C  trickle down to increase sales and bring families into buying racing boats also suitable for the odd cruise.    Maxi's used to be designed with removable interiors  and then they had a go forward life  and trickle down development to production builders,   and jobs for designers.    This crap is of no value  to the sport.    It is  X box childrens games.   Nothing more.

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Successful designer gets the say in the next cup iteration - a la Tom Schnackenberg

What could possibly go wrong? :D

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On 11/23/2017 at 2:55 AM, richiec said:

I thought the cats were fucking stupid. This is even more ridiculous. Can't you just sail yachts, for fucksakes? I supported ETNZ for the last 10 years, all in the hope the cup would come back to the southern hemisphere - and now we are faced with some mongrel/hybrid/vapourware video game shitter. 

Sail BOATS you fucktards!

 

 

Square rigged ships of the line it is!

DRC

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I would love to see the Constitution actually out sailing.........firing its cannons as well.......now that would be a proper starboard hail........what a good idea Clarkie !

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Dummy taks, slam dunks, dyalups, (& downz), soakdownz, shooger daddee funderz & winner tayk orl / pryz munny 

wer orl feecherz ov nayval worfair under sayl.

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30 minutes ago, snaerk said:

Dummy taks, slam dunks, dyalups, (& downz), soakdownz, shooger daddee funderz & winner tayk orl / pryz munny 

wer orl feecherz ov nayval worfair under sayl.

Makes sense to me, snaerk. The added advantage is you don't have to feed the crew and you can flog the bastards if you want too. ;)

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9 hours ago, jorge said:

Only the ones who have challenged for the cup have valid opinions?

For me, yes!!

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Second part is here:

www.sail-world.com/159074

Quote

America's Cup - Dan Bernasconi explains the foiling AC75 - Part 2

Didn't came up at friday as promised though.

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3 hours ago, Fiji Bitter said:

 

Brilliant, Ben Ainslie on the Mary Rose, oops...

The Sinking of the Mary Rose by Geoff Hunt PPRSMA

The Sinking of the Mary Rose by Geoff Hunt PPRSMA

http://www.maryrose.org/discover-our-collection/story-of-the-ship/image-galleries/

Here's hoping Artemis can learn from historical mistakes...

https://en.wikipedia.org/wiki/Vasa_(ship)#Maiden_voyage

On 10 August 1628, Captain Söfring Hansson ordered Vasa to depart on her maiden voyage to the naval station at Älvsnabben. The day was calm, and the only wind was a light breeze from the southwest. The ship was warped (hauled by anchor) along the eastern waterfront of the city to the southern side of the harbor, where four sails were set, and the ship made way to the east. The gun ports were open, and the guns were out to fire a salute as the ship left Stockholm.[14]

As Vasa passed under the lee of the bluffs to the south (what is now Södermalm), a gust of wind filled her sails, and she heeled suddenly to port. The sheets were cast off, and the ship slowly righted herself as the gust passed. At Tegelviken, where there is a gap in the bluffs, an even stronger gust again forced the ship onto its port side, this time pushing the open lower gunports under the surface, allowing water to rush in onto the lower gundeck. The water building up on the deck quickly exceeded the ship's minimal ability to right itself, and water continued to pour in until it ran down into the hold; the ship quickly sank to a depth of 32 m (105 ft) only 120 m (390 ft) from shore.

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Pretty cool that they are going to go for more of an unconstrained box rule...

 

I suspect that will allow some really cool concepts to be tested, and no doubt will be the demise of the teams that either can't re-design and copy fast enough, or just didn't push the envelope enough

 

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45 minutes ago, Tornado-Cat said:

TNZ thinks it's an advantage because they have the designers and P$B because he has the $ to hire the best ones. :)

P$B has the money, and had advanced knowledge of the concept, but we haven't heard much about the design team he is putting together. Does anyone know who the principals are going to be for LR? Seems to be very low key compared to say BMQRA and their Botin press release, or all the Verdier hoopla.

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33 minutes ago, buckdouger said:

P$B has the money, and had advanced knowledge of the concept, but we haven't heard much about the design team he is putting together. Does anyone know who the principals are going to be for LR? Seems to be very low key compared to say BMQRA and their Botin press release, or all the Verdier hoopla.

And it is aligned with the rumors I had from Geneva that they had been testing the concept with boat like Qwants, long before they NZ won the cup

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from https://www.stuff.co.nz/sport/other-sports/99305264/complex-radical-and-expensive--dennis-conner-puts-200m-price-tag-on-winning-2021-americas-cup

Complex, radical and expensive - Dennis Conner puts $200m price tag on winning 2021 America's Cup

America's Cup great Dennis Conner believes a syndicate could require more than $200 million to finance a competitive challenge to take the Auld Mug away from Team New Zealand in the radical new boats to be used in 2021.

Conner, who has won and lost the America's Cup and remains keenly interested in yachting's greatest contest, has given his thoughts on the new AC75 concept unveiled by the Kiwis.

The monster will be complicated, expensive, likely to capsize, but will be "really something", he predicted.

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On 26/11/2017 at 2:32 AM, Indio said:

Has there ever been a Canadian AC Challenge? Just curious..

Most recently Canada 1 competed in the 1983 challenger series and Canada II in the 1987 challenger series.  True North was built for the '87 America's Cup and sailed in the 1986 Worlds, but never competed in the challenger series.

As for Canadian challengers that actually raced in the America's Cup, there have been two:

1876 - Countess of Dufferin

1881 - Atalanta

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22 minutes ago, Tornado-Cat said:

$ 200 M ? Ouch, the first may be winning by attrition !

NZD$200M, but still an expensive winning-campaign estimate by DC. 

"The costs involved are going to be horrific for a low-budget syndicate. Maybe US$100-150m [NZ$145-217m] that's a tremendous amount of money to the folks in sailing. But the best sailor in the world can't win without a good boat and a good team.

"I don't think they want a whole lot of competitors in this event. They are going to limit it to extremely high calibre teams, Teams that are going to be extremely well financed."

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28 minutes ago, ~Stingray~ said:

NZD$200M, but still an expensive winning-campaign estimate by DC. 

"The costs involved are going to be horrific for a low-budget syndicate. Maybe US$100-150m [NZ$145-217m] that's a tremendous amount of money to the folks in sailing. But the best sailor in the world can't win without a good boat and a good team.

"I don't think they want a whole lot of competitors in this event. They are going to limit it to extremely high calibre teams, Teams that are going to be extremely well financed."

All good news for LR and NYYC, ...............only.

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2 hours ago, 12 metre said:

Most recently Canada 1 competed in the 1983 challenger series and Canada II in the 1987 challenger series.  True North was built for the '87 America's Cup and sailed in the 1986 Worlds, but never competed in the challenger series.

As for Canadian challengers that actually raced in the America's Cup, there have been two:

1876 - Countess of Dufferin

1881 - Atalanta

Thank you.

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4 hours ago, 12 metre said:

Most recently Canada 1 competed in the 1983 challenger series and Canada II in the 1987 challenger series.  True North was built for the '87 America's Cup and sailed in the 1986 Worlds, but never competed in the challenger series.

As for Canadian challengers that actually raced in the America's Cup, there have been two:

1876 - Countess of Dufferin

1881 - Atalanta

There is actually a pretty good film on the tube about that 1983 Canadian challenge... totally recommended

 

 

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On 11/25/2017 at 12:11 AM, Basiliscus said:

If the section shape is left for the teams to define, there's no point in trying to limit the angle of attack because the section shape can be designed to produce the desired down force even with a positive incidence on the foil.  

I've no idea what the optimum angle would be for the arms - that's another VPP question.  Say both foils were angled down at the same angle as the lee foil in the normal sailing mode.  Positive lift on the leeward foil would have a vertical component to support the boat and a horizontal component that provides side force to counter the rig.  Negative lift on the windward foil would have a vertical component that provides righting moment and a horizontal component that also helps to counter the rig.  Because of the down load on the windward foil, the leeward foil has to support both the weight of the boat and the down load from the windward foil, so it needs more of a vertical component than it did when the windward foil was retracted.  It may be that the best position for the two foils would be a little lower than shown for the normal sailing mode, but higher than shown for the stable mode.

If the foils were positioned flat as shown in the stable mode, then the side force needs to come from leeway acting on the struts (assuming there are no flaps on the curved struts).  The spanwise load distribution on the horizontal foils will have a discontinuity at the junction.  They will need to have independently articulated flaps on either side of the strut to minimize the drag.  I would expect there to be port and starboard flaps on each foil regardless of how they operate, because of the interference effects of the strut.  There may also be flaps on the strut, and it would make sense for the strut to have a sharper elbow than is shown on the concept sketches so there could be a longer straight segment for the flap.

It could also make sense to put some angle into the cant axis instead of having it straight fore-aft.  This might be used to toe the foils in or out when fully down.  It's not obvious to me whether you'd want all the side force to come evenly from both foils or to be shifted to either the leeward or windward foil.  Since the leeward foil literally does the heavy lifting, it might be desirable to have the windward foil generate the side force so the leeward foil can be optimized for vertical lift with minimum drag.

It's almost as though they built a foil and stuck a boat on top of it.

Would be interesting to figure out a way to have just one foil cant from port to starboard passing under the centerline (Moth) in the gybe instead of two foils.

A balancing act, you'd have to figure out the missing ballast equation. 

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On 25.11.2017 at 2:11 AM, Basiliscus said:

If the section shape is left for the teams to define, there's no point in trying to limit the angle of attack because the section shape can be designed to produce the desired down force even with a positive incidence on the foil.  

It could also make sense to put some angle into the cant axis instead of having it straight fore-aft.  This might be used to toe the foils in or out when fully down.  It's not obvious to me whether you'd want all the side force to come evenly from both foils or to be shifted to either the leeward or windward foil.  Since the leeward foil literally does the heavy lifting, it might be desirable to have the windward foil generate the side force so the leeward foil can be optimized for vertical lift with minimum drag.

If both flap allowable flap angle and angle of incidence is limited by the rules in attempt to limit down force, and section shapes are left for the teams to decide, wouldn't the foil have low L/D while producing upwards lift, it it's designed to allow down force even with a positive incidence on the foil by using cambered section like upside down aircraft wing section?

What about take off speed and efficiency with such foil shapes? Any effect on cavitation speed? On stall angle of attack and/or Cl_max while producing upwards lift?

Do you have something other in mind than just asymmetrical section to produce down force with a positive incidence assuming limitations on flap deflection range in attempt to limit down force (not to prevent it, just limit by making the boat inefficient if using down force in attempt to avoid structural breakages)?

 

What do you think is the sequence for T-foil cant changes for lift off from zero boat speed in light air. Could you describe both leeward and windward movements in sequence.

If initially both are down which one comes up first?

If leeward one, does that mean hull has to have substantial form stability to produce any righting moment long before approaching take off speed and thus dynamic RM? A wide hull has high drag, reducing the critical acceleration rate. First boat out has significant advantage.

If windward one, the leeward foil needs to reverse lift direction during canting process to maintain leeway resistance. How does that change RM during the process, or does it?

 

 

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On 11/26/2017 at 5:32 AM, Indio said:

Has there ever been a Canadian AC Challenge? Just curious..

yep way back in the early early days .... 1881.

The next challenge came from the Royal Canadian Yacht Club and was the first to be disputed between two yachts only. The schooner Madeleine (148.2 tons, 1868), a previous defender from the 1870 fleet race, easily defeated the challenger Countess of Dufferin (221 tons, 1876 design by Alexander Cuthbert). Cuthbert filed the second Canadian challenge, bankrolling, designing and sailing the first sloop challenge for the America's Cup in 1881. The small 65 ft (19.81 m) Canadian challenger Atalanta[16] (84 tons, 1881), representing the Bay of Quinte Yacht Club, suffered from lack of funds, unfinished build and a difficult delivery through the Erie Canal from Lake Ontario to New York. In contrast, the NYYC cautiously prepared its first selection trials. The iron sloop Mischief (79 tons, 1879 design by Archibald Cary Smith) was chosen from four sloop candidates, and successfully defended the cup.

then once in the contemporary times 1983 'Canada 1'

https://en.wikipedia.org/wiki/Canada_One

 

 

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Dan Bernasconi Interview - Sailing Illustrated (Tom Ehman) 

 Another great interview by Tom. He drew out plenty of new info. Below are some notes to the best of my recollection for those that missed it:

 

Hull:
Hull design will be open (to box rule). A big part of design challenge will be hull efficiency, who can get on foils first and who can accelerate fastest. Plus, fans are interested in different looking boats. The hull will ride only 1-2feet above water in normal foiling. 

Foils:
Main Foils: (Foil Arm + Foil Wing) 
- Fixed Wing with Trim Tabs controlling ride height. 
- Electric / Hydraulic controls will raise the Foil in estimated 3-5 seconds. 
- Max Draft in Mooring Mode will be 5m (16ft)

T Foil: will have 2 independent control surfaces (apart from rudder). Either the whole foil will cant fore & aft like AC50, or, the whole elevator (horizontal wing) will pivot. With either system there will also be trim tabs on the elevator.
There is minimal load on T foil, due to being very close to balanced on the Main Foil. DB says, you could almost remove the T foil and have the boat continue sailing (before imminent wipe out..) 

Mast: One design to stop syndicates having to build and test multiple iterations. 

Sails:
Main: Still under development. Mast likely one design (or at least its shape). Reefing is still being determined, but more likely a 2nd smaller main with same loft height but shorter chord will be allowed. 

Sailing:
- Windward Foil will not be allowed to be used submerged for wing generated downforce adding to righting moment (probably above a minimum windspeed). This is to stop syndicates building light air / heavy air boats (with much heavier & very strong rig for extra load). This way the RM loads don't increase much over the wind range and all racing remains competitive.
- Wind range upper limit will not be finalised until initial boats are tested, but DB suggested 25 knots as an initial indicator.
- Prestarts - Boats MAY sail with 2 Main Foils submerged (stability mode). Unknown as yet if it's a benefit. 

Grinding:
Cyclors banned. Grinders efforts will be focussed on sail lofting and trim. 

One Design:
Many parts will be one design to reduce cost. e.g.: Electric / Hudraulic Foil lifting system, controls, bearings etc., possibly the Main Foil Arms (but not wings), the Mast (but not sails). 

Cost:
DB disputed Dennis Connors $US140M cost estimate, saying something like "if that is the case ETNZ don't have a show of winning." He expects costs to be substantially lower through One Design components and that the Protocol will allow syndicates to purchase designs off existing syndicates (e.g. ETNZ, Luna Rossa, BAR)

Dates:
- Design Rule Released March 2018
- First date boat launch March 2019

 

Link to Tom's Blog:

https://www.facebook.com/SailingIllustratedBlog/

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4 hours ago, oobilly said:

yep way back in the early early days .... 1881.

The next challenge came from the Royal Canadian Yacht Club and was the first to be disputed between two yachts only. The schooner Madeleine (148.2 tons, 1868), a previous defender from the 1870 fleet race, easily defeated the challenger Countess of Dufferin (221 tons, 1876 design by Alexander Cuthbert). Cuthbert filed the second Canadian challenge, bankrolling, designing and sailing the first sloop challenge for the America's Cup in 1881. The small 65 ft (19.81 m) Canadian challenger Atalanta[16] (84 tons, 1881), representing the Bay of Quinte Yacht Club, suffered from lack of funds, unfinished build and a difficult delivery through the Erie Canal from Lake Ontario to New York. In contrast, the NYYC cautiously prepared its first selection trials. The iron sloop Mischief (79 tons, 1879 design by Archibald Cary Smith) was chosen from four sloop candidates, and successfully defended the cup.

then once in the contemporary times 1983 'Canada 1'

https://en.wikipedia.org/wiki/Canada_One

 

 

Thank you.

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On 10/9/2017 at 11:02 PM, HFC Hunter said:

ETNZ are saying they want to take trad monohull into the space where they took big foiling cats and help step the monohull game up. They talk about being a pinacle to mono sailing where the the majority of boat owners can relate, and in harmony with other sailing (e.g. Vendee) and not in contrast to them, all with trickle down options. My penny guess:

  • OD wingmast with soft sails. (Sails, and running and standing rigging not OD). I would not be surprised to see new ideas on the mast like controllable battons to play with twist or flutter like a wing.. Blade jibs. High aspect kites off a sprit. I'd hope no electronic trimming aids/cameras, but it'll probably happen.
  • Hull will resemble a boat, skiff-like but narrow. Obvious flat aft sections. Rocker less critical if you're flying. Bow with buoyancy to crash off foils, but still cleave Hauraki chop and not scowed. Vestigal deck and sole minimised to structural and reserve buoyancy needs, but not normal bigboat. Minimal freeboard as boat should be rising. Self bailing without a bucket :) Hull will have crew wings, but more in the spirit of KZ1, not a 49er rack.
  • Rudder t-foil. Probably twin to allow one to aid righting moment. Big-arsed Tiller helming would be cool, but unlikely.
  • Main lift foils will sit under boat on leeward side or from centreline, not wildly outside the beam and not to weather, to allow close match racing action. I expect auto ride height by Foil contour or mechanical wands etc in order to draw focus back to sailing, not gameboy-ing. Centreboard or canards, maybe with minimal weight added but not leadmine. Righting moment control via some crew on wings, some board use, but by foils helping to self-level. Controllable foil surfaces rather than moving entire foils for ride tuning. Possible OD foils, with non-OD controllable surfaces.
  • No hydraulics for sail management. Maybe not for foil tuning either - just sinking and hoisting them.
  • etnz will be black. Prada will be fabulous. Yanks will be stolid/turgid. France1 will be a supermarché and france2 will be LV,MH and all will be nonchalantly Bretagne/Vendee scary awesome this time. Aussie will be gaudi, and weakly backed. Poms will give a knight a job hucking Indian branded cars. I'd like to see the Spaniards arrive and run competing parties to Prada, but they mightn't have the economic appetite for this round.

Damn. Missed with a lot of them pennies. But I like where etnz are throwing the bucks! :)

B949E830-F9BD-4454-AFC9-792C621850D6.jpeg

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I'm very happy the hull is going to be really open design for no other reason than it will be great to be able to tell the boats apart simply by their shape!  The all bosts look basically identical was one of the  more disappointing aspects of the AC50.

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23 minutes ago, Boybland said:

I'm very happy the hull is going to be really open design for no other reason than it will be great to be able to tell the boats apart simply by their shape!  The all bosts look basically identical was one of the  more disappointing aspects of the AC50.

A variety of S shapes on the foil arms could be really fun. Maybe those big foil wings will vary enough to also be cool.

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7 hours ago, hoom said:

The big fail of AC50 rule was to one-design the shape instead of one-designing the structure.

Especially considering they were always going to foil and the shape was almost never going to be in the water anyway!

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So we now know what a foiling Monohull will look like, the next question is how will they sail it?

Will it be standing upright, with the lee foil out to the side, as shown in the promo videos, 

or will the foil be pulled completely down below the hull, and the whole boat being heeled 20 to 30 degrees to windward, like they are doing with the moths.

When a Moth heels to windward, they are in effect making the boat wider (distance from the CoE in the water to CoG above the water), and therefore creating more power and speed.

ALso the lift from the rig will also help to make the boat feel lighter, and therefore faster. This could indeed make the AC75 quicker than the AC50's.

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Can't figure out if I think heeling to windward is harder or easier than keeping the thing vertical. I guess they heeled the AC50s to windward a little in some circumstances. The sailors are going to have to fly those things carefully.

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If the leeward foil is canted correctly, it should not be necessary to heel to windward like a Moth.

But with windward heel, the CoG of the rig would provide some extra righting moment= extra power.

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1 hour ago, Erwankerauzen said:

If the leeward foil is canted correctly, it should not be necessary to heel to windward like a Moth.

But with windward heel, the CoG of the rig would provide some extra righting moment= extra power.

Yes, but the hull would provide less RM more than canceling that out.

The distance from center of lift on the wing of the leeward foil and canting axis of the same foil remains the same. When the hull is heeled, the axis has to climb higher above water or else the hull touches down increasing drag and reducing righting force by having buoyancy as well. With a constant distance, having more vertical component means less horizontal component, hence less righting arm. A result of changing orientation of leeward arm of the foil to more vertical and less horizontal. 

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Don't know if it has been listed here already, but below article on the new boat is quite interesting :

http://www.tipandshaft.com/americas-cup/ac75-ce-quen-disent-les-designers/

In particular it says that Verdier had already worked on the concept retained (with navigator Ray Davies) for a NZ customer on a 39 feet project. The boat didn't get built, but the project is still on-going.

Any Kiwi detective here ? ;)

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On 11/26/2017 at 10:53 AM, Dave Clark said:

Square rigged ships of the line it is!

DRC

Not sure if that would be dumber, other than not going upwind well.

I believe this contest will be in the true spirit of the AC and personally I love this new direction that ETNZ is taking.  It ensures maximum wealth expenditure with no design concept unexplored.  The ill-conceived, the mundane, the insane, it is all on board for the show.  This is what the AC used to be about a very long time ago.  What we now consider to be very traditional was once the future with eye watering costs.  Yachts that used technology never before considered will be once again put on stage no matter the cost and human life be damned.  This is the AC in all its splendor and I eagerly await.

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6 hours ago, NotSoFast said:

Yes, but the hull would provide less RM more than canceling that out.

The distance from center of lift on the wing of the leeward foil and canting axis of the same foil remains the same. When the hull is heeled, the axis has to climb higher above water or else the hull touches down increasing drag and reducing righting force by having buoyancy as well. With a constant distance, having more vertical component means less horizontal component, hence less righting arm. A result of changing orientation of leeward arm of the foil to more vertical and less horizontal. 

If their normal ride height is 1-2ft above the surface, then they can ww heel that amount (minus chop) without adding drag. 

Aside from adding some RM from the rig CoG, they could get other benefits like the vertical lift component from the rig reducing windward foil trim drag, increased heel angle on the foil wing increases lift to windward, lower hull encounters reduced apparent wind speed means less drag as it nears surface, and possibly, with a wide flat hull, some ground effect lift. 

I can see ww heel being used in certain conditions. 

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1 hour ago, yl75 said:

Don't know if it has been listed here already, but below article on the new boat is quite interesting :

http://www.tipandshaft.com/americas-cup/ac75-ce-quen-disent-les-designers/

In particular it says that Verdier had already worked on the concept retained (with navigator Ray Davies) for a NZ customer on a 39 feet project. The boat didn't get built, but the project is still on-going.

Any Kiwi detective here ? ;)

Gtran

28 Nov AC75: what the designers say in America's Cup by admin The presentation, 3D images in support, of the future AC75, on which will be run the 36th America's Cup in 2021, surprised the world of sailing last week. The result of a collaboration between the defender's design teams, Emirates Team New Zealand, and the challenger of record, Luna Rossa, this AC75 - a monohull under an agreement reached between the two parties before the last Cup in case of victory Kiwifruit - has been the subject in recent weeks of many studies. All the options have been studied: from the most classic to the most extreme, going through the evolutions of the current TP52 or Maxi72, before the choice is made on this plan. The dimensions ? They will be unveiled in the rules of measurement presented on March 31, 2018. We know for the moment only the size, 75 feet (overall, 68 feet for the hull). But according to our information, the hull width should be 5.3 meters for a displacement of 7 tons - crew of 10-12 sailors not included - with a recovery moment of 45 tons / meter. Finally the possibility of a thick mainsail is under study. The gauge will also determine which elements will be monotypes, to limit costs (we speak of the mast, a part of the foils and their systems), while freedom will be left for the design of the hull. "We do not want all boats to look the same as on the last Cup, we want the differences to be visible, not just experts," says Martin Fischer, who now works in Luna Rossa's design team. The only restrictions will be to make the performance of the boats comparable. " This plan, if it seems revolutionary, is not quite new, since a project has already been studied by Guillaume Verdier, member of the New Zealand design team led by Dan Bernasconi. "With the Ray Davies navigator, we had developed this monohull concept with weighted side foils to offer it to a private client in New Zealand, we have never built the boat, but the project is still in progress," confirms l interested in Tip & Shaft. "Guillaume Verdier had already worked on a project of 39 feet and that's probably why they went in this direction, they do not start from nothing, this boat has already turned in their models, it's reflected" adds Dimitri Despierres, former Oracle, who like Joseph Ozanne and Michel Kermarec, recently committed to the challenge of the New York Yacht Club. In concrete terms, how will this AC75 work? "It's a boat that has two modes: classic when it sails with the weighted foils under the boat, and as it accelerates, the dynamic mode takes over, the foils can lift the boat that s 'Then press the foil under the wind while the other allows to bring up the recovery torque and stability out of the water in the wind, explains Guillaume Verdier. For the foils, there was a big design work with Bobby Kleinschmidt and Steve Coolie, the idea was to have a boat that has an initial stability, it will not be a 75-foot moth. "The other advantage weighted foils are explained by Martin Fischer: "They act as tilting keels, suddenly, the boat will stand up alone with the foils if desalinated." The concept, if it needs to be refined, seems in any case seduce: "We were a little afraid that they go to something traditional or more bastard with a keel and foils as seen in Imoca. There, it's really exciting, we start from a blank sheet, the stake in the design process will be to simulate to understand how the boat will fly and identify the directions and possible differentiations, "confirms Philibert Chenais, design engineer at Land Rover-BAR. Same analysis in Dimitri Despierres who is delighted with the bias of innovation: "I'm really happy, it's smarter to go for the recovery moment by the width and the foils, rather than dragging lead for nothing. In technological evolution, this path is totally logical. And, in my opinion, this technology will be easier to transpose on everyone's boat than it was for AC50s. " The last word is for Vincent Lauriot-Prévost, co-founder of the firm VPLP: "The video is interesting, because it's all new, but I wonder if what we see there prefigures what it will be or if it is an example among others. Basically where are the constraints, what fields of investigation will be free, on what we will be able to play? ". Reply by 31 March at the latest ...

 

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57 minutes ago, ~Stingray~ said:

…Dimitri Despierres who is delighted with the bias of innovation: "I'm really happy, it's smarter to go for the recovery moment by the width and the foils, rather than dragging lead for nothing. In technological evolution, this path is totally logical. And, in my opinion, this technology will be easier to transpose on everyone's boat than it was for AC50s."

Seriously? Will it be common in a few years for monos to have articulated foils that extend their beam by 3 fold, with all the mechanical, hydraulic and electrical paraphernalia that entails?

I can't wait to see if this concept works and what the resulting racing will be like, but I just can't see it being adopted by anyone outside the AC. Especially when there is no failsafe: if the foil raising or lock-down mechanisms fails (supposing it has one), the boat will capsize. That might be tolerable on a high performance racing boat sailed by the world's best with large onshore crews and tenders in close support, but for weekend warriors scraping to get a crew together, probably not.

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2 hours ago, yl75 said:

Don't know if it has been listed here already, but below article on the new boat is quite interesting :

http://www.tipandshaft.com/americas-cup/ac75-ce-quen-disent-les-designers/

In particular it says that Verdier had already worked on the concept retained (with navigator Ray Davies) for a NZ customer on a 39 feet project. The boat didn't get built, but the project is still on-going.

Any Kiwi detective here ? ;)

Very interesting - talk about a head start, wonder if LR knew that ...

Still a mystery who the LR head designer is - Martin Fischer confirmed, but it cannot be him

Equally interesting, NYYC is staffing up with ex-OR Frenchies: Kermarec, Ozanne, Despierres - good

 

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19 hours ago, pacice said:

When a Moth heels to windward, they are in effect making the boat wider (distance from the CoE in the water to CoG above the water), and therefore creating more power and speed.

Look at the pic again, the foil is far to leeward like a moth at extreme windward heel, then they've effectively canted the rig back upright.

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1 hour ago, Xlot said:

Very interesting - talk about a head start, wonder if LR knew that ...

Still a mystery who the LR head designer is - Martin Fischer confirmed, but it cannot be him

Equally interesting, NYYC is staffing up with ex-OR Frenchies: Kermarec, Ozanne, Despierres - good

 

Despierres, in French (long)

 

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  ^  Conference / job orientation for the benefit of (youngish) engineering students - so a good general overview, well done but little new info and on the past Cup. He does confirm OR's kaputt and he's now with another US team.

Back to the Tip&Shaft piece, it's the first time I hear 75' include the bowsprit, the boat is 68' LOA - and 5.3 m beam

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1 hour ago, ~Stingray~ said:

^ Where best yachting action in the world is, they are truly brilliant boats.

Let's hope that AC75 will compare. The action is taking place in front of Ouessant or Pointe du Raz if I recognize the coast correctly.

BP IX was splashed in October in Lorient, Armel Le Cleac'h gives himself 1 year to fly correctly. Contrarily to Edmond de Rothschild, their foils move in all directions.

http://www.letelegramme.fr/voile/maxi-trimaran-banque-populaire-ix-le-cleac-h-c-est-aujourd-hui-que-tout-commence-30-10-2017-11722305.php

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4 hours ago, ~Stingray~ said:

^ Where best yachting action in the world is, they are truly brilliant boats.

Meh. Pretty good form for a French multi. But hardly the best yachting action in the world, Stinger. But your enthusiasm does you credit.

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7 hours ago, Tornado-Cat said:

BP flying on 3 foils, and 2 up, very nice...

Actually flying on two from time to time…

Banque Populaire X oops.png

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7 hours ago, Tornado-Cat said:

BP flying on 3 foils, and 2 up, very nice...

Holy shit :blink:

How does their ride-height work, they got an engine & auto-pilot running it?

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3 hours ago, hoom said:

Holy shit :blink:

How does their ride-height work, they got an engine & auto-pilot running it?

There must be some kind of auto-pilot, Armel Le Cleac'h trains for the Route du Rhum, which means crossing the Atlanctic,.....SOLO !

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4 hours ago, hoom said:

Holy shit :blink:

How does their ride-height work, they got an engine & auto-pilot running it?

The UptiP ama foils have intrinsic(designed in) altitude control that works with very little adjustment. Ama foil rake is controlled from the panel below-but constant adjustment is not required. The center foil is manually controlled like it is on Maserati and Gitana. Manual control is shown in the second picture at the top where it is labeled "Rake Derive".

1st pix: picture credit from Ultim boat's post in Timeline Photos----2nd pix: picture credit: voile.bankpopulaire.fr

Banque Populaire UptiP ama foils.jpg

Banque Populaire foil control voile.bankpopulaire.fr.jpeg

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For the time being "auto pilot" for the foils is forbidden by the "Utlim class"(collectif ultime), I think.

But this is a point of disagreement with Gitana team (and reason for them not being part of the collectif), which has put some form of it, not sure about the status of it all.

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I imagine the functions of the autopilot maybe expanded to potentially include adjustment of the main foil and possibly irregular adjustment of the ama uptip foil.

Rudders are controlled by the autopilot so there is absolutely no reason to prevent foil adjustments.....

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6 hours ago, Doug Lord said:

'maybe expanded to potentially include'

You just might be right, Doug - but I'd be reluctant to commit myself one way or the other.

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On 12/6/2017 at 4:44 AM, Doug Lord said:

I imagine the functions of the autopilot maybe expanded to potentially include adjustment of the main foil and possibly irregular adjustment of the ama uptip foil.

Rudders are controlled by the autopilot so there is absolutely no reason to prevent foil adjustments.....

Yeah, I don't understand the idea that an autopilot can adjust the horizontal heading of the boat through manipulation of a foil (rudder), but it should be banned to have foils/flaps automatically adjust what is effectively the "vertical heading" of the boat.

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2 hours ago, GauchoGreg said:

Yeah, I don't understand the idea that an autopilot can adjust the horizontal heading of the boat through manipulation of a foil (rudder), but it should be banned to have foils/flaps automatically adjust what is effectively the "vertical heading" of the boat.

I think that is what he means...

Why would you want to ban it ? 

 

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Seems like the big problem with auto control of the foils would be reaction and anticipation in rapidly changing conditions, ie large waves.

How about a joy stick control, I know that it wouldn't work for the solo sailor when he's off the helm but there could be some speed made if you literally flew the boat thru the waves.

Then again,  I guess there is some pretty sophisticated terrain following software if you can pry it away from the military.

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On 11/27/2017 at 12:14 AM, Boybland said:

Here's hoping Artemis can learn from historical mistakes...

https://en.wikipedia.org/wiki/Vasa_(ship)#Maiden_voyage

On 10 August 1628, Captain Söfring Hansson ordered Vasa to depart on her maiden voyage to the naval station at Älvsnabben. The day was calm, and the only wind was a light breeze from the southwest. The ship was warped (hauled by anchor) along the eastern waterfront of the city to the southern side of the harbor, where four sails were set, and the ship made way to the east. The gun ports were open, and the guns were out to fire a salute as the ship left Stockholm.[14]

As Vasa passed under the lee of the bluffs to the south (what is now Södermalm), a gust of wind filled her sails, and she heeled suddenly to port. The sheets were cast off, and the ship slowly righted herself as the gust passed. At Tegelviken, where there is a gap in the bluffs, an even stronger gust again forced the ship onto its port side, this time pushing the open lower gunports under the surface, allowing water to rush in onto the lower gundeck. The water building up on the deck quickly exceeded the ship's minimal ability to right itself, and water continued to pour in until it ran down into the hold; the ship quickly sank to a depth of 32 m (105 ft) only 120 m (390 ft) from shore.

That ship was recovered and restored to her former glory in Stockholm, minus several pieces of gold leaf for cost reasons, making do with gold paint instead. It's an amazing ship and you really have to be there to realise how big this fucker is. 

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9 minutes ago, See Level said:

Seems like the big problem with auto control of the foils would be reaction and anticipation in rapidly changing conditions, ie large waves.

How about a joy stick control, I know that it wouldn't work for the solo sailor when he's off the helm but there could be some speed made if you literally flew the boat thru the waves.

Then again,  I guess there is some pretty sophisticated terrain following software if you can pry it away from the military.

Terrain following radar would be too big and cumbersome for such a boat, lasers maybe or use a wand. Besides the military would never give away how their TFR works even if the concept is well known. Price, weight, power usage all go against using such a system. It is blooming amazing though. Making TFR software though is much more feasible and Prada gave their TFR software to ETNZ in ac35 which gave them that silky smooth ride. Minus the capsize.

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On 12/6/2017 at 7:11 PM, Sailbydate said:

You just might be right, Doug - but I'd be reluctant to commit myself one way or the other.

Let's be honest, their auto pilot probably already has this factored in. To what extent the auto pilot controls the foils remains to be seen. 

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9 minutes ago, Raptorsailor said:

Terrain following radar would be too big and cumbersome for such a boat, lasers maybe or use a wand. Besides the military would never give away how their TFR works even if the concept is well known. Price, weight, power usage all go against using such a system. It is blooming amazing though. Making TFR software though is much more feasible and Prada gave their TFR software to ETNZ in ac35 which gave them that silky smooth ride. Minus the capsize.

I would suspect that a wand system linkages might be pretty stout.  Not a delicate solution is my guess.

Not that it is relevant to the particular problem of keeping a foiling sailboat in contact with the water - or as advanced as the military's system for flying at hundreds of miles an our over lumpy dirt - but didn't the S&R helicopters sent out on the '98 Sydney Hobart rescues had surface-following systems that maintained a constant height over the waves.  Is that sort of device common?  I seem to recall a story where one of the choppers set their stabilizer at a specific GPS height by mistake and were a little surprised when a wave rolled right beneath them.

Thankfully I'm too old to consider foiling through the southern ocean.

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43 minutes ago, Raptorsailor said:

... Prada gave their TFR software to ETNZ in ac35 which gave them that silky smooth ride. Minus the capsize.

BS..90% of the control system for AC35 was developed in-house at ETNZ.

27 minutes ago, Left Shift said:

I would suspect that a wand system linkages might be pretty stout.  Not a delicate solution is my guess...

ETNZ's AC35 control system is proven to manage & control the constant foil adjustments required, and can be automated even further - if they allow it full automation in the AC75 Class Rule. The other side of the equation is the availability of full power on tap as demanded by the automated control system.

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3 hours ago, Raptorsailor said:

Let's be honest, their auto pilot probably already has this factored in. To what extent the auto pilot controls the foils remains to be seen. 

What system would it use to determine adjustments? Simply sensing the surface at one or two locations (e.g. simple active sensor such as a wand, laser, etc.) is insufficient. Scanning might work, but that needs hugely more computing power and sophistication. It would also need to accommodate the central foil breaching, which seems to be fairly frequent (or maybe they just showed that bit for the JLAT* factor).

Maybe a set of accelerometers with some pretty sophisticated analysis tools (AI?) could determine settings from the feel of the boat. Now that would be cool.

* Jesus, look at that!

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3 hours ago, RobG said:

What system would it use to determine adjustments? Simply sensing the surface at one or two locations (e.g. simple active sensor such as a wand, laser, etc.) is insufficient. Scanning might work, but that needs hugely more computing power and sophistication. It would also need to accommodate the central foil breaching, which seems to be fairly frequent (or maybe they just showed that bit for the JLAT* factor).

Maybe a set of accelerometers with some pretty sophisticated analysis tools (AI?) could determine settings from the feel of the boat. Now that would be cool.

* Jesus, look at that!

a couple of accelerometers at either end of the boat is all you need and some software that activates a foil trim command...

rather than trimming the yacht to ride above the water at a set height...... you would want the yacht to be relatively steady and the foil depth to vary in relationship with the wave height.

 

The skipper can make larger adjustments ( ride height to crest the waves )  while the accelerometers just try and balance out any unwanted vertical movement if there is any detected but not input.

 

I had some software in my car a few years back called DCCD pro, and it basically increased a 5 Volt signal the more + G force it sensed. ( had twin accelerometers ) and a simple map as well as a sensitization setting. should be pretty cheap to make.... from memory that was $300 - $400 bucks. 

 

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11 hours ago, Indio said:

BS..90% of the control system for AC35 was developed in-house at ETNZ.

ETNZ's AC35 control system is proven to manage & control the constant foil adjustments required, and can be automated even further - if they allow it full automation in the AC75 Class Rule. The other side of the equation is the availability of full power on tap as demanded by the automated control system.

I thought ETNZ's system was all Prada's work. Thanks. 

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The New America’s Cup Design

8DEC

Posted by Brian Hancock 

I really don’t want to be negative.  I love innovation and I really appreciate that a lot of time has gone into developing a creative new idea for the 36th America’s Cup. I am not sure what else they could have done, but I do have one idea. They could have stayed with multihulls…:)

http://greatcirclesails.blogspot.com/2017/12/the-new-americas-cup-design.html

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15 hours ago, dachopper said:

a couple of accelerometers at either end of the boat is all you need and some software that activates a foil trim command...

rather than trimming the yacht to ride above the water at a set height...... you would want the yacht to be relatively steady and the foil depth to vary in relationship with the wave height.

 

I think it's a lot more complicated than that.  Yes, sensors are relatively cheap but processing the input to know what adjustment to make isn't. A foiling boat has movement in 3D,  and accelerometers drift, so there also needs to be a system to provide a datum, or maybe ventilation is it. I expect that in an ocean setting at 30 kn, working out which waves you can drive over or through and those you need avoid has to happen before they reach the boat, and certainly before any reactive system can act.

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1 hour ago, ~Stingray~ said:

The New America’s Cup Design

8DEC

Posted by Brian Hancock 

I really don’t want to be negative.  I love innovation and I really appreciate that a lot of time has gone into developing a creative new idea for the 36th America’s Cup. I am not sure what else they could have done, but I do have one idea. They could have stayed with multihulls…:)

http://greatcirclesails.blogspot.com/2017/12/the-new-americas-cup-design.html

. At the risk of challenging the design team, who I know are infinitely more smarter than me, I am going to say that I don’t think that this is going to work very well.
 
Sums it up nicely.
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43 minutes ago, Terry Hollis said:
. At the risk of challenging the design team, who I know are infinitely more smarter than me, I am going to say that I don’t think that this is going to work very well.
 
Sums it up nicely.

The design team claim they want to do for monohulls what they did for multihulls. The problem is that if you want to go foiling then no-lead multihulls are the obvious choice primarily for the light-weight reason. Hancock nailed it.

They tried to accommodate P$B’s coerced condition that it be a big monohull, but with the hope it could be as beastly-fast as the AC50’s. That premise was an all around questionable basis for the boat and trickle-down to mono’s looks unlikely any time soon.

Shrug, here’s hoping the admittedly-crazy Tri-Transformer works as advertised, it could be a development quite damn wild to watch.

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