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6 minutes ago, zillafreak said:

 

So tell me Terra, since you seem to be quite the denier, what you think the of the video from 1:36 to 1:41. I know you like to look at simple pictures but video is better. Is that your typical reflection? Maybe they are different down there.

For the 3rd time watch the video at the 3.07 min mark. Why is there nothing there and during other times there is also nothing there? 

 

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It's pissing down outside and yes, we are back to Level 3. To all those moaning and bitching about it and calling the PM childish names, get a grip, we are the luckiest people in the world right

After many hours of consideration, a lot of in-depth research on the SA technical threads, extensive computational modelling and a few quick & dirty minutes in Photoshop, I have produced this anal

They towed out around 11am and the breeze was light and puffy to start with. Foiled down the Channel and headed out to the Bays. The breeze started to build around midday and they got some long runs i

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49 minutes ago, amc said:

If they have done their sums correctly and have the right tail volume ratio, there will be a degree of longitudinal static stability. That said there are a lot of moving forces to deal with. 

" tail volume ratio "... what is that ?

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1 hour ago, zillafreak said:

Wow y'all are fucking blind. Go to full screen from 1:36 to 1:40 or so and tell me you dont see it. Clear as day

 

942011159_ScreenShot2020-11-19at8_31_42PM.png.5b1b6fb96ac7d3926d0faac6ece584db.png1331673999_ScreenShot2020-11-19at8_31_25PM.png.e3137113f89ad5a20e328b125e6f604b.png1959034749_ScreenShot2020-11-19at8_30_51PM.png.3757b0e1bc5f69068804d19ef69b424c.png1703014485_ScreenShot2020-11-19at8_30_51PM.png.49b2c858b1edb1ba074d8cca4631e35a.png

These were all taken at different times. Awesome reflection that stays at the same spot.. Ya fucks. Get a clue

 

Screen Shot 2020-11-19 at 8.31.03 PM.png

Fuel filler caps.

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10 minutes ago, MaxHugen said:

Hmmm... the Google translator is useless... what does "Te Rehutai" mean?

(Haven't read all 500+ posts in the last ~24hrs!)

‘’Where the essence of the ocean invigorates and energises our strength and determination.”

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someone asked me about the phone zoom i did of @desprit 's photo of the sheeting arrangement. I tried a better zoom, pushed the pixels around. Made some wild guesses as to what's back there. The bottom of the clew board is not in shot so probably some more interesting stuff to see. Hopefully in the weeks to come there will be some other shots.

 

 

mainsheet.jpg

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7 minutes ago, Barnyb said:

Spy shot from a new angle - including the obligatory SA yellow line.

I am doing the hard yards for you guys!

20201120_165234b.jpg

Shit mate, worse places to be than Soul on a Friday afternoon!

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Doing my nerdy thing, I thought the mast had a lot of bend for a section 650mm x 400mm!

So I had a closer look at the Rig Plan (20.3), and although I doubt it accurately shows mast detail, there is evidence that the mast reduces it's cross-sectional size, but only around ~21m.

image.png.c36d610552b156ce22b58da2c0d9b35a.pngimage.png.8b2d98b1c3e9f5c6b0f8a51bcd377d12.png

I note from the lower mast angle that the boat appears to have a hull AOA of -2°.

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3 hours ago, MaxHugen said:

Correction. The Rules show the MRP (reference plane) as the interface  of the bottom point of mast rotation with the deck, which must be 1.5m above the MWP.

So @JALhazmat is right, the deck at the mast is not lower, the crew pods are raised.

image.thumb.png.fa7cac372a4b12c0cda94b634b1d4f6c.png

Ah thank you :)

 

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12 minutes ago, Ex-yachtie said:

Interesting shot from Live Sail Die of the foil arm.  I was (incorrectly) expecting to see the widening of the foil arm fairing at the waterline, and was surprised to see the amount of curve in the trailing edge.

B188883D-E409-4D05-B197-0C73FB931BC1.jpeg

Very interesting indeed!

I wonder if it's an asymmetrical section (only at that extended fairing section) that they're trying to get some extra lift from, pre-take-off when the foil cant is probably lower so the section is in the water?

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6 minutes ago, MaxHugen said:

Very interesting indeed!

I wonder if it's an asymmetrical section (only at that extended fairing section) that they're trying to get some extra lift from, pre-take-off when the foil cant is probably lower so the section is in the water?

It potentially increases lift on the foil arm and reduces leeway when getting foiling 

its also easy to copy if there is an appreciable Benefit 

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26 minutes ago, JALhazmat said:

It potentially increases lift on the foil arm and reduces leeway when getting foiling 

its also easy to copy if there is an appreciable Benefit 

Yeah, I'd have to check all the angle of the dangles, but it may be more to do with reducing leeway initially.

A reaction that's a fraction of a second slow in mainsail trimming (2:13), and windward heeling causes the foil to start surfacing (2:14 or less), so loss of lift and windward foil dragging, and a minor splashdown (2:15). At the speeds these boats do, that could cost half a boat length or more:

image.png.14594d4de37de089b5f0afb1f40ad285.png

 

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2 minutes ago, Horn Rock said:

Good first day sailing. Performing dry manoeuvers straight off the bat. She looks a weapon. Has an imposing presence on the water with that shape.

Wasn’t all dry though, none of the teams are and even nz b1 touched so let’s not get carried away. 

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52 minutes ago, Ex-yachtie said:

The crew (one from each side) are swapping side, in front of the mast.  I didn’t think that was allowed...

I thought so too, but the Rule allows Brief crossing in front of mast to swap sides or handle Sails. Any further forward though lifelines required. Crew not allowed inside the Hull at all so no rabbit holes under the deck allowed. 

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7 minutes ago, Horn Rock said:

Good first day sailing. Performing dry manoeuvers straight off the bat. She looks a weapon. Has an imposing presence on the water with that shape.

They have some training yet to perfect, which is not unexpected considering it's their first day out in B2. Watch from:

Weren't fast enough to correct the hull AoA via the stabilator.

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Just now, MaxHugen said:

They have some training yet to perfect, which is not unexpected considering it's their first day out in B2. Watch from:

Bit of a whoopsie there Max. I know all the boats are the same weight, but Te Rehutai has a heavy, bull shark like look about her. Quite different to the almost feminine, don't step on my handbag Prada.

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Those "reflections" line up with the track for the traveller, so they may be something to do with how that was installed or some external variance caused by internal bracing required by it.

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2 hours ago, MaxHugen said:

" tail volume ratio "... what is that ?

There are lots of references on the interweb and they mostly give me a headache reading them coz I’m not that smart but roughly if the tail (Rudder foil in this case) area multiplied by the distance from the main foil ( i.e. area x distance  called volume by convention)is correct for the main foil size, shape etc then an airplane (yacht) can be designed to be stable in pitch. It still requires some adjusting while under way but nothing too drastic. If this were not the case then it would be impossible to fly ordinary airplanes. Interestingly relaxed static stability is good in some cases  like fighter aircraft. But in this case fly by wire control systems do the hard graft and the pilot just decides where to point the thing. Computer does the rest. Something like that anyway. Keep up the great work though you are way beyond what I can do. 

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Still not exactly pretty, but sails up you can see what the design is meant to do, certainly looks like everything lines up!

Interesting to see the bow blast here as well

Not an Amway fan but if I had to guess I'd agree with above saying Amwagic vs NZ final

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7 minutes ago, Boybland said:

Those "reflections" line up with the track for the traveller, so they may be something to do with how that was installed or some external variance caused by internal bracing required by it.

Ha! Little hole for pulling the car off the track? Just cover it with vinyl and we'll sort it later..

As someone who tries to be objective, i think there's enough pics to support both sides of this odd argument, pretty sure we'll get a better idea over time

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6 minutes ago, RMac said:

Ha! Little hole for pulling the car off the track? Just cover it with vinyl and we'll sort it later..

As someone who tries to be objective, i think there's enough pics to support both sides of this odd argument, pretty sure we'll get a better idea over time

I was actually thinking more along the lines of feeding the whole track through, but yeah I'm not convinced either way, was just pointing out that if they are on either side they do line up pretty well with an internal feature as well.

Of course they could just be the petrol caps for the gas tanks.

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3 hours ago, amc said:

If they have done their sums correctly and have the right tail volume ratio, there will be a degree of longitudinal static stability. That said there are a lot of moving forces to deal with. 

11 minutes ago, amc said:

There are lots of references on the interweb and they mostly give me a headache reading them coz I’m not that smart but roughly if the tail (Rudder foil in this case) area multiplied by the distance from the main foil ( i.e. area x distance  called volume by convention)is correct for the main foil size, shape etc then an airplane (yacht) can be designed to be stable in pitch. It still requires some adjusting while under way but nothing too drastic. If this were not the case then it would be impossible to fly ordinary airplanes. Interestingly relaxed static stability is good in some cases  like fighter aircraft. But in this case fly by wire control systems do the hard graft and the pilot just decides where to point the thing. Computer does the rest. Something like that anyway. Keep up the great work though you are way beyond what I can do. 

Ah, OK gotcha, just a matter of terminology.  You're right, the pitch (hull AoA) is governed by the rudder foil's force. This "stabilator" has to change it's AoA to provide either positive or negative force to (1) support ~20% of the total hull mass, and (2) balance the sail driving force.

Around the time the boat is foiling, the stabilator has changed from providing Lift, to Downward force.

 

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I don't think there is a boom. Hence the huge range of clew attachment to alter the sheeting angle and pull the depth out of the foot upwind / twist.  Prob a hude clew board between the two skins with a hydraulic adjustment. 

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Looks great sailing, you can see the evolution from Te Aihe and the influences of Te Kahu when you're not looking from strange angles.

 

2 hours ago, ivansh said:

So what's the control configuration? It seems like at least two people cross, but they're not helm (unless they're steering it from the middle). Is it trim/flight control? Are there two drivers now?

The rendered launch video had a centre helm position with a grinder behind

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19 minutes ago, Boybland said:

Of course they could just be the petrol caps for the gas tanks.

I've been through a stack of photos from the launch and can confidently say it was a reflection. Both sides in question are pristine flat, but the whole side of the boat is quite glossy reflective - I am seeing the foil arms reflected in the hull which I don't ever remember seeing on Te Aihe.

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1 hour ago, minimumfuss said:

I thought so too, but the Rule allows Brief crossing in front of mast to swap sides or handle Sails. Any further forward though lifelines required. Crew not allowed inside the Hull at all so no rabbit holes under the deck allowed. 

Actually the rules are as follows:

28.8 Crew shall remain entirely aft of a plane 9.0 m forward of TRP except briefly to cross the boat, handle sails
during a drop or a hoist, or resolve unforeseen issues.
28.9 Any crew that go forward of a plane 11.0 m forward of TRP may only do so as permitted by Rule 28.8, and
must be tethered to the hull by a harness and safety line that complies with ISO 12401, the safety line
being no longer than 2 m.
Now the MRP (aft end of mast) has to be 9150mm fwd of TRP +/- 10mm

I can't find the rule for the mast at the moment, but IIRC it was 600mm fore and aft.

So that leaves 1.35m forward of the mast before the crew exceed the rule that requires a safety line. What the rule doesn't say is whether that is any part of the crew or his torso or whatever. So it would be very easy for someone going forward of the mast to have his arm out for balance (as they do) and for part of that arm to extend beyond the 11m line. Or even for part of the torso to extend beyond there.

I wouldn't be surprised if there are protests from those teams who don't have crew crossing in front

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It does look like a much better implementation of the INEOS trench and boomless configuration that INEOS dropped.

INEOS trench wasn't as clean with no pod walls. And INEOS never seemed to be able to flatten the bottom of the main.  

See how steep the sheeting angle is on the INEOS boomless set up. Just can't get enough foot tension.  

(edit: this shot does look to be downwind, so maybe that depth is okay, but upwind it looks just as deep)

INEOS Team UK grinder David Carr explains what it's like to sail an AC75

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2 hours ago, Forourselves said:

Wonder if we'll see a few hull mods from the challengers over the next few weeks?

Wait, so ETBZ absolutely could not have copied any of the challengers in the last 6 weeks (as we were told yesterday), but you think the challengers could modify their boats in 2 weeks?

I didn't realise that ETNZ were so slow in comparison

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Just now, enigmatically2 said:

Wait, so ETBZ absolutely could not have copied any of the challengers in the last 6 weeks (as we were told yesterday), but you think the challengers could modify their boats in 2 weeks?

I didn't realise that ETNZ were so slow in comparison

Well, who knows, Oracle modified their boat literally overnight in 2013.

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This what happens when you try to use battens to 'push' camber out of a sail. 

INEOS TEAM UK: Innovating better and faster with the digital twin | Siemens

 

I think this was as good as the INEOS boomless set up got.Not too dissimilar to what the Kiwis have noe. But looking at teh huge cutout NZL has is does look like they have more range in their sheeting angle. 
America's Cup: Back on home waters >> Scuttlebutt Sailing News

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50 minutes ago, Horn Rock said:

Yep, she's boomless. There's two big arse battens down near the foot of the main. You can see them in the pic -

Te_Rehutai_bl.jpg.6246b09a2a4232712e3fa726e0a8e562.jpg

I can't seen any particularly big battens? There's a couple of tension creases in the sail. 

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11 hours ago, The_Alchemist said:

Really the first competitor to give a shout out to AM as a formable challenger.  Everyone else seems to take them lightly.

My favourite Challenger Team NYYC AM is very well-respected by Kiwis for a number of reasons: the history of NYYC in the AC, the team's attitude since they launched their challenge, the Kiwi-like way in which they've gone about their business without any distractions, Hutch's history with ETNZ, Barker's involvement.

Make no mistake: win or lose, NYYC will be CoR in AC37 unless they beat us, in which case they will have RNZYS/ETNZ as CoR.

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This is what I see. Red is traveller. Blue is mainsheet. Green is an adjustable clew board for sheeting angle / twist. Pink are 'skirting' lines just to neaten up the shape below the clew board. 

Then there is a couple of creases where excess cloth is folding under tension and being brought down in to the deck. Downwind when the clew lifts these might drop out to maintain a tight fit against the deck. 

But I don't see any evidence of super thick battens 'pushing' camber out of the foot. 

battens.jpg.09a731b6864520128dda7ac8c36600b1.jpg.af422dcbffd8ff12ae599201d1e66cec.jpg

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2 minutes ago, Indio said:

My favourite Challenger Team NYYC AM is very well-respected by Kiwis for a number of reasons: the history of NYYC in the AC, the team's attitude since they launched their challenge, the Kiwi-like way in which they've gone about their business without any distractions, Hutch's history with ETNZ, Barker's involvement.

Make no mistake: win or lose, NYYC will be CoR in AC37 unless they beat us, in which case they will have RNZYS/ETNZ as CoR.

If ETNZ win I wouldn't be surprised to see INEOS as CoR, they are more aligned with the Kiwis on the whole foiling thing. NYYC sounds good in theory as a CoR, but they want traditional monohulls, Bellamente style.

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44 minutes ago, Horn Rock said:

In this pic it looks like the lower battens are attached to the main/traveler.

battens.jpg.09a731b6864520128dda7ac8c36600b1.jpg

We need our member with the magic "AI Zoom Enhancer" program to help out here!  Want to clearly see it "bigly". ;)

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@Horn Rock I'm not sure. Just saying what I see. 

But, in a system that is working well I don't think creases are unlikely. Upwind you want to pull hard along the foot to flatten the sail. So any excess cloth will bunch in creases. And you will be sheeting hard on the leech to for power so the clew (and foot of the sail) pulled down in to the deck. It was quite breezy upwind sailing in this video. I'd expect them to drop out downwind when they sail with a fuller sail. 

In ineos final boomless set up they had a a similar skirting line along the foot to neaten up below the clew (you can see below). But I don't think they had enough range of movement on the clew board for the mainsheet attachment. It also looks like NZL have two skirting lines. 

 INEOS TEAM UK

 

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4 hours ago, Ex-yachtie said:

So this is what sailors look like now. 
 

(Sorry about the screenshot Blair)

A34351C2-A38D-4F98-87BD-E39E92454D1E.png

Seems to me it's kinda what most sensible people look like who face 60+kn winds while outside getting wet, skiers, motorcyclists etc, no?

3 hours ago, MaxHugen said:

Very interesting indeed!

I wonder if it's an asymmetrical section (only at that extended fairing section) that they're trying to get some extra lift from, pre-take-off when the foil cant is probably lower so the section is in the water?

Rules....have you read them? Fairings may not transmit loads etc?

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29 minutes ago, Horn Rock said:

They seem to like this "mode" of shallow flying. Not much arm in the water, and the bit that is has that narrowing. Might be fast?

But they’re the only ones with zero-anhedral foils, right?

 

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1 hour ago, The_Alchemist said:

foil tip out of the water

Seems to be a bit of a trend ATM. Amway are doing it often and Frackers sometimes on the vids I've seen .

Have to say, B2 for NZL looked pretty good on her first outing.