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And we have liftoff!!

I for one was happy to finally see an American team that didn’t just reek of assholes. Terry was a great bloke to have in front of the cameras and the intimate videos behind the scenes I found quite f

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1 hour ago, Stingray~ said:

(squinting) Are they foiling on only the port-side main foil in that clip?

It is hard to tell, but yes, the starboard foil is just barely visible in the upright position. It blends in with the black hull.

The foils are positioned quite forward of where past renderings show on the AC75 or on T5.

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2 hours ago, 2Newts said:

This is an interesting video. They are up on foils in less than 10 knots in fewer than 10 days on the water. Something has gone right. 

I'm interested now in their partnership with Airbus. From the press release, Airbus will be providing "simulation capabilities development, systems architecture design and testing, hydrodynamic calculation and optimization, boat control and instrumentation." (emphasis mine)

So now this team has proven that they have a design team that can get a boat into the water that works right off the bat, they have in Airbus one of the premier builders of simulators and arguably the premier designer of flight control systems, they have in Penske an organization devoted to speed, and they have a sailing team that knows how to win. Not a bad way to start. 

 

https://www.sailgp.com/news/simulating-success

So under the AC36 rules, can AC teams use simulators like the Artemis Tech one for crew training to get virtual in-water time?  They cannot tank test hulls but I cannot recall what other prohibitions...? 

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3 hours ago, 2Newts said:

This is an interesting video. They are up on foils in less than 10 knots in fewer than 10 days on the water. Something has gone right. 

I'm interested now in their partnership with Airbus. From the press release, Airbus will be providing "simulation capabilities development, systems architecture design and testing, hydrodynamic calculation and optimization, boat control and instrumentation." (emphasis mine)

So now this team has proven that they have a design team that can get a boat into the water that works right off the bat, they have in Airbus one of the premier builders of simulators and arguably the premier designer of flight control systems, they have in Penske an organization devoted to speed, and they have a sailing team that knows how to win. Not a bad way to start. 

 

Don't forget Airbus was involved in the last AC too - with at least one of the unsuccessful teams.

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28 minutes ago, NeedAClew said:

https://www.sailgp.com/news/simulating-success

So under the AC36 rules, can AC teams use simulators like the Artemis Tech one for crew training to get virtual in-water time?  They cannot tank test hulls but I cannot recall what other prohibitions...? 

Yup see my post in other thread ;-)

Simulator was key to ETNZs success and it's a key component in AC36 prot.

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4 minutes ago, nav said:

Don't forget Airbus was involved in the last AC too - with at least one of the unsuccessful teams.

Which is not dispositive necessarily because we don't know how their involvement might be different this time, not yet anyways. We also don't know what they may have learned from last time. What we do know is that the ENTZ 'flight control' system was a key competitive advantage in Bermuda, and we we know that Airbus' capabilities in aeronautical flight control are unsurpassed. From there, it's a matter of drawing conclusions or making assumptions. Or both. Or just conjecturing. 

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5 hours ago, 2Newts said:

Which is not dispositive necessarily because we don't know how their involvement might be different this time, not yet anyways. We also don't know what they may have learned from last time. What we do know is that the ENTZ 'flight control' system was a key competitive advantage in Bermuda, and we we know that Airbus' capabilities in aeronautical flight control are unsurpassed. From there, it's a matter of drawing conclusions or making assumptions. Or both. Or just conjecturing. 

I think we simply conflating the words 'flight control' now... 

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7 hours ago, nav said:

And you clearly don't need dihedral, maybe not even flaps!?

Dihedral on these foils is the equivalent of an acute V on the early cats.  Makes them easier to sail but is almost certainly slower.

Disclaimers.

1. I haven't read the rule so there may be a small Australia II keel style advantage of dihedral letting you build slightly bigger foils.

2. Some dihedral may let you decouple lift and lateral resistance thus asking less of any given foil thus increasing speed before cavitation becomes an issue.

 

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5 hours ago, Fireball said:

???? They are on port tack - have a look at the start of the clip when the boat is not foiling and is heeling to starboard. 

Indeed, the later part of the video its hard to tell if its on port or starboard but the start can surely only be on port & there's no tack.

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1 hour ago, Stingray~ said:

Bingo

It is so obvious when looking at the START of the clip. 

Feeling quite stupid at this point.

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On 11/5/2018 at 4:56 PM, NeedAClew said:

Indeed she does.  So how fast do you estimate? (Anybody know what the bird was and how fast they fly?)

I love the earlier MP references.  The birds that fly past look quite large and are dark in color.  I would guess they are crows (which are common on the coast of RI) and the literature states that they typically have a cruising speed in the 25 - 32 mph range.

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31 minutes ago, Chapter Four said:

Gybes like and early AC72 foiling gybe:o, I'm sure they'll get there though

But could an AC72 or even an AC50 (well yea, but just at its limit) foil in a breeze that light? There does not seem to be enough breeze to sustain the ride through the jibe, but with more time on the foils, they will nail it.

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21 hours ago, Chainlocker said:

But could an AC72 or even an AC50 (well yea, but just at its limit) foil in a breeze that light? There does not seem to be enough breeze to sustain the ride through the jibe, but with more time on the foils, they will nail it.

it looks to me like the second foil produced too much lift when it entered the water and they got too high out of the water.  When they learn to balance the lift on the foils they should be able to gybe on the foils.

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27 minutes ago, Kiwing said:

Nice Video, Wow if this is what is the standard at this early stage we are in for a great build up and an very competitive group of Challengers.

Looks like a D mast and twin skin to me.

watching it a few times it looks like a D mast but it looks they have a central track on it as well and have a single skim main on at the moment. 

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7 minutes ago, hoom said:

Notice tip interaction with the surface, something avoided by the brits.

yep, though I doubt that these are the last foils that they will play with on this boat. could just be that they're starting with totally flat foils just to get a data baseline. 

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1 hour ago, frozenhawaiian said:

new vid is out with some high def, albeit short clips of the boat up on the foils. sure as hell isn't  slow. definitely like flat foils and I can't tell if it's a D profile mast. or not. 

 

On 7/4/2018 at 2:04 AM, dogwatch said:

There's an awful lot of grey hair in that picture. I don't think the AC75s are going to be grey-hair friendly.

This mule looks better in concept than the UK mule

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1 hour ago, frozenhawaiian said:

how so? the UK boat I understand is really just a foil test bed, this is meant for more than just foil testing, really different animals 

The US boat seems closer to a functional AC75 than the UK boat which as you say is a foil test bed. Foils are one thing however the US boat seems like a better all round train and test platform at a quick glance? 

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22 minutes ago, terrafirma said:

Foils are one thing however the US boat seems like a better all round train and test platform at a quick glance? 

It's bigger than Mini-Frack, and looks to be going quicker. The complete difference in foil geometry is interesting.

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2 minutes ago, Horn Rock said:

It's bigger than Mini-Frack, and looks to be going quicker. The complete difference in foil geometry is interesting.

yeah I noticed that, seems like it's going way faster. but again it's a bigger boat, and as has been said it's certainly a more refined craft. 

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Just now, Kiwing said:

This looks like the d mast?  but does not show the central track.395716946_NYYCDmast.jpg.f9ae50f1b6a8521d77656f3133c2cc86.jpg

hard to tell with all the crap sitting on top of it if there's 2 outer tracks as well as a central one. but yes that does certainly look like a D mast.

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2 minutes ago, frozenhawaiian said:

it's a bigger boat, and as has been said it's certainly a more refined craft.

Yeah more length, and way more beam than the Quant, thus the absence of the training wheels seen on Mini Frack. It seems to be way more stable straight off the bat as well. 

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48 minutes ago, PuckSoppet said:

What’s the LOA of the Mule 38? Unless they’ve cut the back off the MC38 (doesn’t look like it to me) it must be bigger than the 12m LOA allowed in the protocol?

 

Since it’s not defined in the Rule, I believe they adopted the (majority) interpretation of LOA which considers the hull only, excluding appendages like bowsprit, rudder gantries etc.

 

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4 hours ago, hoom said:

I meant to say earlier its nice to see more of the foiling initiation, looks pretty smooth.

Indeed, but I wonder how much of that is software/autopilot controlled at the moment?  Ineo$ was running 2axis autopilot and the real things have to be manual controls.

 

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On 10/28/2018 at 4:08 PM, chesirecat said:

Yep. Looks like what a bunch of T52 sailors with limited foiling experience would put together. 

Are we dialing back the photoshopped, these guys have no clue statements yet??

:P

 

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One nuance that's being at least partially missed here is that these upgrades are both done on existing boats. A q28 in short order and an MC38 with some care have been radically turboed. It's work but if you look at the accumulated hours in incrementally upgrading Wild Oats XI vs the total rebuild of the mule, it's not so different. We're looking at a AC rule that might well lead to a pile of revolutionary upgrades to boats like IMOCAs V65s and even billion dollar pigs like maxi boats. You could go back and make Commanche competitive for outright records, rather than outright "monohulls only" records. If you already love maxis and ocean racing monohulls, you won't see that as a big deal, but if you're confused by the ongoing presence of monohulls at that scale, like I am, this is a serious development.

DRC

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1 hour ago, Dave Clark said:

One nuance that's being at least partially missed here is that these upgrades are both done on existing boats. A q28 in short order and an MC38 with some care have been radically turboed. It's work but if you look at the accumulated hours in incrementally upgrading Wild Oats XI vs the total rebuild of the mule, it's not so different. We're looking at a AC rule that might well lead to a pile of revolutionary upgrades to boats like IMOCAs V65s and even billion dollar pigs like maxi boats. You could go back and make Commanche competitive for outright records, rather than outright "monohulls only" records. If you already love maxis and ocean racing monohulls, you won't see that as a big deal, but if you're confused by the ongoing presence of monohulls at that scale, like I am, this is a serious development.

DRC

This. By replacing the 'canting keel PLUS foils' paradigm with 'canting ballasted foils', you now have a system that can both foil and leverage the full righting moment of the multis, yet can also (theoretically) recover from a capsize, since you've eliminated the outboard archimedian component that both keeps multis upside down when they go over, and also seems to be becoming a greater structural liability at flying speeds. And as you note, just like the IMOCAs that were converted to foiling, this looks very doable for existing canters.

 

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A lot of the video is gorgeous production work. Thumbs up!

Never did understand all the rampant speculation earlier in the thread about Shopping; and in this video the boat looks exactly like it did in the first photos of the launch event. 

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1 hour ago, Purple Headed Warrior said:

What is that batten/boom pole at the bottom of the main?

Boat looks incredible, they are going to get some incredible data from this beast to put into the AC75!

I wonder what the real AC75 hulls will look like...

Where do you see it? Something visible in this shot?

 

0B70EC8B-A8AB-4ACC-B2ED-2854E12DA8FF.thumb.png.71b01b7390eeee050cf1251894830c0b.png

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53 minutes ago, Stingray~ said:

The wake to the left, slightly trailing the foil arm’s wake, is a little interesting.

 

D5073747-43DF-4FF4-B3F1-ADC73DD5C59F.thumb.jpeg.63b57a03cda4a2a65d15fcb3fd5db173.jpeg

For them to get some foil inefficiencies in the first week of sailing is not a problem. Whether they got too close to the surface, or whether this foil is actually reaching it's max speed, or other cause - whatever it is I suspect they are simply pleased that v1.0.0 of the boat gets up on foils and stays up. From here they have all winter to tune it until they are allowed to launch the full size boat in (IIRC) March. 

Speaking of winter, though, are they going to sail this thing all winter out of Hinkley in RI? It gets something cold in Feb...

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4 hours ago, surfsailor said:

This. By replacing the 'canting keel PLUS foils' paradigm with 'canting ballasted foils', you now have a system that can both foil and leverage the full righting moment of the multis, yet can also (theoretically) recover from a capsize, since you've eliminated the outboard archimedian component that both keeps multis upside down when they go over, and also seems to be becoming a greater structural liability at flying speeds. And as you note, just like the IMOCAs that were converted to foiling, this looks very doable for existing canters.

 

Fuck me dead! Turns out this concept is great! Whowouldathunkit?! ;-)

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1 hour ago, Stingray~ said:

The wake to the left, slightly trailing the foil arm’s wake, is a little interesting.

 

The video shows it coming & going. 

It looks like the foil tip is not broaching the surface. 

I am think a "tip vortex" or something similar is the cause.

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1 hour ago, rh2600 said:

Fuck me dead! Turns out this concept is great! Whowouldathunkit?! ;-)

It's a cool idea for sure, once you've accepted the concept of having the massive amounts of stored power that makes the canters work. Since the IMOCA boats etc are already there, this is a logical next step, and I'm sure that the design that Verdier was already working on before ETNZ won in Bermuda was aimed in that general direction. With regards to the AC however (except the anomaly of AC33), stored power is new, and - if your goal was to bring back classic style match racing - what works for IMOCA is not automatically going to work for that.

Having said that, the new F50s have also gone to stored power, so I think that particular evolution was inevitable.

 

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48 minutes ago, Kiwing said:

@Purple Headed Warrior I think this is a twin skin main (I could be wrong ?) but that batten puzzles me too?

Twin skins 1 NYYC.jpg

Twin skin sails need what we call a 'zero batten' to stabilize the bottom edge of the leeward skin, that has relatively low tension plus a fairly large separation bubble near the trailing edge and (to a lesser degree) along the entire foot.

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3 hours ago, Stingray~ said:

The wake to the left, slightly trailing the foil arm’s wake, is a little interesting.

Its what I was referring to.

 

We saw that quite a bit with AC-72 J foils, less so with the AC50 foils which mostly kept the tips away from the surface.

Its somewhat obscured on the cats with the tip being inboard & the rudder wake being in line.

 

The Team Basher anhedral style keeps the top foil close to horizontal -> tip away from surface.

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2 minutes ago, hoom said:

Its what I was referring to.

 

We saw that quite a bit with AC-72 J foils, less so with the AC50 foils which mostly kept the tips away from the surface.

Its somewhat obscured on the cats with the tip being inboard & the rudder wake being in line.

 

The Team Basher anhedral style keeps the top foil close to horizontal -> tip away from surface.

We've been going around and around on this with kite foils, which have nearly identical flying orientation to the AC75s. In theory, a bell-shaped lift distribution should let you get away with surface penetration at speed (since the lower AoA at speed means the washed out wingtips are basically lift neutral) but in practice the wings with anhedral are still better. However, the kites are very small scale relative to the water surface roughness, and extremely dynamic since they have very little inertia, so this could well work on a much larger and exponentially more stable platform. The advantage of a flatter wing would be earlier takeoff and or being able to use a smaller, less draggy wing. The disadvantage would be (as I've noted before) less control isolation between Z and Y axis lift.

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1 hour ago, surfsailor said:

Twin skin sails need what we call a 'zero batten' to stabilize the bottom edge of the leeward skin, that has relatively low tension plus a fairly large separation bubble near the trailing edge and (to a lesser degree) along the entire foot.

I don't see the separation bulb or much other evidence of the twin skins (unless you are suggesting that that batten is evidence of twin skins?). but looking at the D section in previous image it appears to have just two male tracks?

But it is all so new and puzzling (for me) it will be fun trying to piece together the evidence to get near the truth.

Anyway it looks like a great round of experimenting and learning

Twin skin NYYC 11-11-18.png

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5 hours ago, 2Newts said:

For them to get some foil inefficiencies in the first week of sailing is not a problem. Whether they got too close to the surface, or whether this foil is actually reaching it's max speed, or other cause - whatever it is I suspect they are simply pleased that v1.0.0 of the boat gets up on foils and stays up. From here they have all winter to tune it until they are allowed to launch the full size boat in (IIRC) March. 

Speaking of winter, though, are they going to sail this thing all winter out of Hinkley in RI? It gets something cold in Feb...

 

been wondering that a well, I love living in new england but the sailing around here come February isn't what one would call ideal. winter base somewhere in florida I would guess?  

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Sails look the go. Having Q to rival NS can only be good for the whole sport.

Think that large batten 150-200 could well be the primary linking of the two skins and keeping the trailing edge as thin as possible whilst also allowing the small amount of slip that the geometry would occur.

I am not a betting man but would wager that the oval section "batten" is actually two halves - split vertically with an internal linkage along maybe the last 600-1000mm of aft most length.

The amount of tell tales placed on the sail in PHW's post of #1077 show how much they are trying to monitor any separation bubble both windward and leeward as well has having laminar flow off the trailing edge. 

It is also definitely a twin skin mainsail that is being tested

The two skins of the main sail are clearly visible in the same photo - look at the curved windows - you can make out the lewward windows of the leward skin are clearly separated apart - with the depth decreasing from front to back as the skins taper back to touching each other somewhere aft or around the back of the window.

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2 hours ago, Horn Rock said:

Just having a mild poke at Kiwing, because every post of his is about the twin skins.......

Hey @Horn Rock you at least read my posts, Thank you.

But seriously, perhaps the engine is up there in importance. And I believe it could be one of the big differences in the boats.  Changing it's shape quickly from full power to high velocity performance as the apparent wind moves forward as they go up onto foils.

It is interesting to speculate.

@Horn Rock do you suggest there will be little difference in the sails or sail performance?

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3 hours ago, Kiwing said:

do you suggest there will be little difference in the sails or sail performance?

Differences between the twin skin setup, as well as the foils, could lead to massive speed differences between the boats. Being the first iteration of this rule and everyone starting with essentially a clean sheet, we could end up with four very different looking boats. It will be fascinating to find out who has the best solution. This could be the most open cup in years. Instead of just being a smidge quicker, the winning boat is likely to be in the order of knots faster. Performance through manoeuvers and transitions will of course be important as well, not just straight line speed.

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If that really is a twin skin sail, it would be more interesting to focus on the top (rather than bottom) batten - with associated reverse camber controls. Aldo, I don’t see a leech line (fond Lady Helmsman memories .. )

 

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Looking forward to seeing these things race!

The "photos" on sail-world are just shots from the video.

A ruler seems to me like a great way to drive a flat head screw!

Foils like those would be quite the upgrade for your average keelboat!

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2 hours ago, Stingray~ said:

If so, does the slot visible under the wrap on the right strongly suggest it’s a double-skin? 

Yes. If you look at the very first picture, you can see a batten pocket in line with the sail groove. Since we now know it’s a D spar, this should mean there’s two of them, as opposed to the single boom gooseneck

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9 minutes ago, Xlot said:

Yes. If you look at the very first picture, you can see a gooseneck in line with the sail groove. Since we now know it’s a D spar, this should mean there’s two of them

2 goosenecks and one boom? how does that work? 

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14 hours ago, Kiwing said:

I don't see the separation bulb or much other evidence of the twin skins (unless you are suggesting that that batten is evidence of twin skins?). but looking at the D section in previous image it appears to have just two male tracks?

But it is all so new and puzzling (for me) it will be fun trying to piece together the evidence to get near the truth.

Anyway it looks like a great round of experimenting and learning

Twin skin NYYC 11-11-18.png

Look at the shot from aft and look through the window. Twin skin sail which is separated far further back than the diagram above - unless shopped. 

 

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