Boats and foils comparison

Stingray~

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Maybe its a weight balance to prevent/ensure correct twist of the foil? are they even allowed dynamic control of the foil? Thought it was just the arm.
They do design their own (fixed) fairings for the trailing edge of the foil arms but they will actively tune the trailing edge flaps of the foil wings. 

The tip-ups on Sardine’s wings will surely need to have flaps in order to stay in tune along with the rest of the wing; one of the purposes for the sharklets could be to house actuators for flaps along that section of the wing?

 
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barfy

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Maybe its a weight balance to prevent/ensure correct twist of the foil? are they even allowed dynamic control of the foil? Thought it was just the arm.
15.5 Through a foil flap’s range of rotation angles and twists, a foil flap cross-section shall not significantly
deform except as permitted in Rules 15.4, 15.8 and 15.9, or as a result of external forces.


15.8 A foil flap may contact a foil wing, and in the absence of external forces, and at any cross-section and
rotation angle, either may cause deformation in the other in a single zone covering not more than 20% of
the local chord length. Outside this zone, neither shall cause deformation in the other.


15.9 Connections between sections of a foil flap are exempt from Rules 13.9, 15.4 and 15.5, providing such
connections span a combined total of no more than 10% of the span of a foil wing, where the span is
measured along the rondure.


looks like some deformation allowed between different sections of flap, maybe that's the flap that some noticed near the wing root.

 

Stingray~

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either may cause deformation in the other in a single zone covering not more than 20% of
the local chord length.
Almost reads like ‘bending’ or controlled morphing is allowed between the wing and the flap, within those limits. 

It is pretty hard to make out any ‘hinge’ existing between the wings and the flaps in the foils that LR launched with.

 
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Ex-yachtie

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Don't be so fast to say that the torpedo design has more drag.  The long wing foils of NZ have a very long leading edge and surface area that all creates drag.  The Torpedo is one large mass, but it is efficient in the amount of drag it creates (less surface area for a given mass).  There has to be more surface area in a pair of long wings than in a torpedo and two small wings.  Also, The long wings of the NZ foils may create too much lift and thus have to be adjusted (flaps, angle, etc...) to keep the boat stable as they sail.  The increased drag for the adjustments and longer foils can really slow the boat down.  If NZ doesn't have a VMG trick (like the last cup), they may get up quickly but be hunted down by AM.
I don’t think ETNZ’s foils are much longer than LR’s. 

 

Tornado-Cat

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Boats are so different that I predict we will have the most important distance between first and second in the AC history.

The best teams now are taking high resolution photos of each team, make 3 D models and test it in their simulator. A the same time they try to figure out the polar of each B1.

At this game the defender has 3 months advance for B2 and may already know the wind limits that should be announced December 20th 2019 ("match conditions").

The competitor with the best concept out of the box or able to wait for this time and with the means to copy and improve the best present concept should win.... with a distance.

 
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But still a simulator and not real life, so I think we are on the same page.... 

“What we were seeing in the wind tunnel and what we were seeing on the track was a very different situation,” he explained. “It took until after [the 2014 Hungarian Grand Prix] to actually get everyone to agree and understand that there were big correlation issues, and they made some really good work after that, they understood it and 2015 was much better.”

“There’s a lot of correlation issues, yeah,” he said. “The rest is downforce, also, and it’s not really good in terms of pure numbers. But the biggest issues [are] correlation – behaviour on track versus wind tunnel.

“If you believe wind tunnel and everything, it’s all good and it’s all getting better. If you believe the lap time and feeling and what we’re measuring on track… not so much. So that’s what we’re really trying to analyse at the minute: what’s really the problem, and [what’s] causing the correlation issue?”

https://www.formula1.com/en/latest/article.grosjean-2019-haas-problems-remind-me-of-2014-lotus.7ui4ZHzppAALAJfqUhuZyr.html

Who do you think has s better grip on wind tunnel and simulation, F1 or AC?

 
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Tornado-Cat

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This is where I think that Orca would have an advantage with a flat hull, she would rebound instead of crashing. Notice that it confirms what I said, that a crash would put Flipper on the side  (as when they crashed on the foils first time out). (photo credit weta27)

Capture.PNG

 

Sailbydate

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This is where I think that Orca would have an advantage with a flat hull, she would rebound instead of crashing. Notice that it confirms what I said, that a crash would put Flipper on the side  (as when they crashed on the foils first time out). (photo credit weta27)

View attachment 325021
C'mon, TC. As you saw, Flipper popped right back up and carried on. We've seen nothing even close to an Orca crash land (similar to Flippers) so what do you base your assumptions/conclusions on? Wishful thinking? I'm not buying it. 

 

darth reapius

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This is where I think that Orca would have an advantage with a flat hull, she would rebound instead of crashing. Notice that it confirms what I said, that a crash would put Flipper on the side  (as when they crashed on the foils first time out). (photo credit weta27)

View attachment 325021
You wouldn't think a flat bottom would grip the largest area of water causing it to stick the most?

I would have thought TNZ would be the best for bounce-back and AM would be the worst...

 

Lakrass

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Feels good to come back to this thread and see they have put the wrap back on RB1 (first post), best for us all if TC doesn't update that one.

 

Tornado-Cat

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C'mon, TC. As you saw, Flipper popped right back up and carried on. We've seen nothing even close to an Orca crash land (similar to Flippers) so what do you base your assumptions/conclusions on? Wishful thinking? I'm not buying it. 
Well, we have two flat boats, one "rounded belly" and one light V, so will see soon. W'll see who is right but it will be a key component of the winning boat.

Ever did water skying, sailed a sailboard ? if you jump and want to rebound on, what do you want a rounded hull under your foot or a flat ?

 
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