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INEOS Team GB

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There's a reason the optimum VMG angle is the optimum VMG angle. Every moment you spend off it is a negative. 

The boats are relatively light for their rig size. As soon as they exit the power zone those big rigs are pure drag and being light they won't have the moment to avoid quick deceleration. 

Plus, with the hull out of the water, there won't be the same drag penalty of 'twisting' a straight hull through a turn. 

Even with skiffs, it's always better to do a quick turn. And that's still with dragging a fat arse through the water. The only limit of how fast you turn is your ability to move yourself at the same time.... which these boats don't have.  

The holding momentum for VMG gain on heavier boats is a bit of a red herring. It's never a VMG gain, but just less of loss as you have smaller sails (less drag head to wind) and more momentum relatively to maintain forward movement. 

So, I'd say the shortest time between VMG on one tack or gybe to other the better. The limit will be the foils 'skidding' out and stalling with the increased side loading of the turn, and of course how quickly they can get the new foil down and set to 'catch' the boat on the new tack (plus how quickly they can invert the main). 

 

 

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But there are losses from a quicker turn too Mozzi, more rudder angle and the main foils are less head on so will be less efficient. Part of my doubt is that I can't see anything stopping all the teams turning more quickly. The headsails are very quick, the foil movements are quick. LR doesn't even have to change sides, so why not speed it up?

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6 hours ago, Horn Rock said:

Pretty sure all the others have at least two to go. AM may have four left. If it's true Ineos have used all their foil allocations, it points to a haphazard development program. Considering their Bermuda debacle, one is not entirely far fetched in describing Ben as a great sailor, poor to average team manager.

I'm not sure what the lead time is on a foil assembly, but it may be 3-4 months.

So even if one of the teams was to come out with something truly revolutionary, then the others would struggle to make a set for themselves in time for March, or even earlier when it comes trying to win the Prada Cup and face the Defender.

I guess having them out a bit earlier would give them more time to fine tune, understand, perhaps make minor changes or even major ones since they'd have the time left.

The whole set up of this cup is all about balancing so many factors and decisions, and each team may end in a different sweet spot with what they designed and optimised for.

Super intriguing. One would think that with all these supercomputing available to the teams they could really determine the same sweet spot, the same ideal foil shape and arrangement, the same sail shapes and the same hull shape.

 

Then there's the question of how much of a difference can the sailing crew make. It may be that boats are within 2-3% of each other, and a the very best sailing crew could make all perfect manoeuvres and in the end cover the course at 7% more average speed. 

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Yeah, I get that rudder is a brake. But, you either use a smaller amount of rudder for longer, or a larger amount of rudder for shorter. So the penalty adds up the same. Using too much rudder becomes an issue when you stall it, which is very draggy. On heavy dinghies and yachts if you use too much rudder this happens, you end up not turning quickly, but just stalling and dragging the rudder. After all, you have a hull that wants to go straight working against a rudder that is trying to turn the boat. 

But it's close to what I am saying above skidding out. If you turning to quickly, the rudder could stall, This would cause drag, and you would stop turning. Or if the main foil loses grip you again get lots of drag, and you skid sideways. So I think they might be limited by how quickly their foils let go (just like a racing car losing grip in a turn).

I also think it's about co-oridnating control too. No point the helm spinning the wheel supper fast if the  foil can't be dropped and flaps then trimmed to provide lift as the weight is transferred to the outside of the turn. Or the main trimmer can takes 2-3 second to invert the main.. etc

Potentially some issue are limited by structural loading on the boat and foils?

But, if your systems are good enough, your foils don't stall, and the boat can take the load, then from a performance point of view the less time you spend off VMG the better. 

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55 minutes ago, MastaVonBlasta said:

I'm not sure what the lead time is on a foil assembly, but it may be 3-4 months.

That would be true for large, complex shape, composite foils like for AC50s

Smaller, simpler foils that can be machined out of solid metal stock, it’s a matter of a few days

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20 hours ago, MastaVonBlasta said:

 

That is not an inspiring video...

More touch down turns, tacks or jibes!

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3 hours ago, enigmatically2 said:

But there are losses from a quicker turn too Mozzi, more rudder angle and the main foils are less head on so will be less efficient. Part of my doubt is that I can't see anything stopping all the teams turning more quickly. The headsails are very quick, the foil movements are quick. LR doesn't even have to change sides, so why not speed it up?

A sailing boat doesn't need a rudder to turn, indeed efficient turns are thru boat/rig trim and not the rudder. 49ers, for instance, have relatively small rudders which cause drag and stalling so they have to be kept really flat, especially mark rounding so minimal rudder is used.

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3 minutes ago, chesirecat said:

A sailing boat doesn't need a rudder to turn, indeed efficient turns are thru boat/rig trim and not the rudder. 49ers, for instance, have relatively small rudders which cause drag and stalling so they have to be kept really flat, especially mark rounding so minimal rudder is used.

Indeed I know, not just from racing but from teaching rudderless sailing in uni holidays.

But faster turns require (more) rudder, not just to speed up the turn but also to stop the angular momentum. That or lose power before and after. Especially since I don't think using the angle of heel is an option here

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My observation is that it's not just the speed of the turn that is going to help, it's also stance through the corner.

INEOS is probably the best example from the other boats of riding quite high through the turn and then taking a second or two to re-establish equilibrium on the new foil and the ride height they are looking for in a straight line.

Patriot doesn't go in as high but she also has an ungainly turning stance, often nose down and leaning in to the corner.

Te Rehutai and Luna Rossa have a more flat-to-the-water turning stance and look more balanced and stable coming out of the turn, more so TR than LR.

It's this period immediately after the turn has been completed where the "sit-downs" often happen..

Could TR and LR be using more cant in their working foil arm, so the foil is providing more lateral force through the turn, and to stay low? Perhaps TR have the choreography of this worked out better than LR.

LR occasionally does some real snappy turns so they are capable of it, but perhaps not so easy in a light breeze?

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2 hours ago, Ex-yachtie said:

This is why I'm here. :D

Ha, ha. On a wing and a prayer. Funny as fuck. ;-)

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1 hour ago, weta27 said:

My observation is that it's not just the speed of the turn that is going to help, it's also stance through the corner.

INEOS is probably the best example from the other boats of riding quite high through the turn and then taking a second or two to re-establish equilibrium on the new foil and the ride height they are looking for in a straight line.

Patriot doesn't go in as high but she also has an ungainly turning stance, often nose down and leaning in to the corner.

Te Rehutai and Luna Rossa have a more flat-to-the-water turning stance and look more balanced and stable coming out of the turn, more so TR than LR.

It's this period immediately after the turn has been completed where the "sit-downs" often happen..

Could TR and LR be using more cant in their working foil arm, so the foil is providing more lateral force through the turn, and to stay low? Perhaps TR have the choreography of this worked out better than LR.

LR occasionally does some real snappy turns so they are capable of it, but perhaps not so easy in a light breeze?

I agree on the Ineos turns, the most recent footage seems to link the re established equilibrium with the swapping of sides of either the flight controller or main trimmer

if you look closely at this swap, it is being done very very slowly with no urgency to the body language or movement.  its fair to say that its either they cant be fucked or its deliberately slow.

given the people in those roles I would edge towards deliberate. they have also shown much faster smoother maneuvers previously than they seem to be doing  in close proximity to the others.

LR have no swap/minimal swap thing going on and NZ are scurrying around flat out on the side swap 

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On 12/2/2020 at 6:23 AM, Grrr... said:

They have GOT to be kidding.  $899 for a 6 hour boat trip?  Holy shit.  Someone's been drinking the Koolaid about yacht owners all being rich.

No joke, the land-based official AC hospo packages for a nine-hour day are NZ$995.

A thousand bucks for a tent and free piss!!!

https://www.experiencegroup.co.nz/americascuphospitality/hospitality.php?ln=Land-Based-Package&LID=946551601

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  ^ And team swag is in line: a LR beanie (which is the only thing I might consider without looking ridiculous) - 100$ US!

 

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899 to watch the round robin is a joke. Can get some very nice piss and watch at home from a fraction of that!

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Ineos look fine in a steady breeze on what look to be largish area foils. Whether they're comparatively fast is questionable though. I get the impression they've dialed back thoughts on pushing the design boundaries. Settling for a let's just get around the track clean and hope the others don't. 

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3 hours ago, Xlot said:

 

  ^ And team swag is in line: a LR beanie (which is the only thing I might consider without looking ridiculous) - 100$ US!

 

Should be considerably cheaper in, April 2021, no? ;-)

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1 hour ago, Lat35sowth said:

Plenty of real estate agents need somewhere to spend their suitcases of money...

I heard they were all lining up outside Continental Cars, Newmarket for their new Audi RS Q8's? That must have been back in October, then. ;-)

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2 minutes ago, porous_morris said:

Nice shot of the bendy boom here. Do we have any ides how this is working?

bendy boom.PNG

That's a lot of camber down there at the boom!  I see it then decreases quite a bit towards the top of the pic.

No idea how the boom is set up though.

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On 12/2/2020 at 5:45 AM, weta27 said:

Probably not much help ..?

controller1.jpg

Based on the size of the name on that vest that's got to be either Bleddyn Mon or Iain 'Goobs' Jensen who are both listed as Mainsail trimmers - I think it's Goobs. Have we figured out if they've listed 2 mainsail trimmers because they're sharing duties on each side or are running Bleddyn as a back-up?

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1 hour ago, porous_morris said:

Nice shot of the bendy boom here. Do we have any ides how this is working?

bendy boom.PNG

My money is on the little orange hand held  box..  

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22 hours ago, enigmatically2 said:

But there are losses from a quicker turn too Mozzi, more rudder angle and the main foils are less head on so will be less efficient. Part of my doubt is that I can't see anything stopping all the teams turning more quickly. The headsails are very quick, the foil movements are quick. LR doesn't even have to change sides, so why not speed it up?

Because the teams have recorded every turn they've ever made, and studied the speed throughout the turn.  By doing some fairly simple mathematics they've figured out which turn rate results in the smallest loss, and the driver almost certainly has a target rudder angle for a given input boat speed for any turn.

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16 minutes ago, Grrr... said:

Because the teams have recorded every turn they've ever made, and studied the speed throughout the turn.  By doing some fairly simple mathematics they've figured out which turn rate results in the smallest loss, and the driver almost certainly has a target rudder angle for a given input boat speed for any turn.

So why the big differences between the teams and even different tacks

FWIW I have times several turns and GB seems to vary from 6s to 12s from new foil entering water to old foil coming out of water. When they are in 6s to 9s it seems to be cleaner, above that and they seem to touch .

NZ (from a more limited sample) are at 6s.

It maybe that GB are (deliberately?) not trying to do clean tacks when they are practising something else but seems odd because you want it to be routine

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17 minutes ago, enigmatically2 said:

So why the big differences between the teams and even different tacks

FWIW I have times several turns and GB seems to vary from 6s to 12s from new foil entering water to old foil coming out of water. When they are in 6s to 9s it seems to be cleaner, above that and they seem to touch .

NZ (from a more limited sample) are at 6s.

It maybe that GB are (deliberately?) not trying to do clean tacks when they are practising something else but seems odd because you want it to be routine

It will be routine by the time they are racing.  They may still be gathering data, but you can bet on every single maneuver they are recording every motion and analyzing what they should do in every condition and the timing of each.  They will know exactly how far they turn the rudder, when the foils should come up and down, and everything else.  It wouldn't surprise me if they have indicators for each, much like they do for shift points in formula 1.

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16 minutes ago, Grrr... said:

It wouldn't surprise me if they have indicators for each, much like they do for shift points in formula 1.

Tad different with a foiling sail boat. Wind, sea state, current, puffs/lulls....It's like no two manoeuvers are alike. Three guys have to have a feel for the manoeuver and be in sync......crew technique will play a tangible role.....as will executing on the day.

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40 minutes ago, Horn Rock said:

Tad different with a foiling sail boat. Wind, sea state, current, puffs/lulls....It's like no two manoeuvers are alike. Three guys have to have a feel for the manoeuver and be in sync......crew technique will play a tangible role.....as will executing on the day.

Not that much. Boat speed will be high whatever so the rate of turn will be much more consistent than most displacement boats, waves won't be an issue for the conditions these things are racing in, current makes no difference (apart from to waves) and the whilst the timing of the tack may be chosen for a lull for example, the rest should be pretty consistent for a well drilled crew. 

But for whatever reason at the moment it isn't for GB and it shows how well they stay up. They plainly are no mugs so I don't believe it is poor crew-work or training, or even the boat design for that matter, but I can't figure out why it does vary so much

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21 minutes ago, enigmatically2 said:

Not that much. Boat speed will be high whatever so the rate of turn will be much more consistent than most displacement boats, waves won't be an issue for the conditions these things are racing in, current makes no difference (apart from to waves) and the whilst the timing of the tack may be chosen for a lull for example, the rest should be pretty consistent for a well drilled crew. 

But for whatever reason at the moment it isn't for GB and it shows how well they stay up. They plainly are no mugs so I don't believe it is poor crew-work or training, or even the boat design for that matter, but I can't figure out why it does vary so much

FYI...

Waves do affect them, they have to fly higher, so foil can't be canted as much, RM suffers, and aerodynamics will also be affected.

Current will affect them, the foils create drag, just as a displacement boat does.

But all the data that's collected will give a switched-on combination of CFD nerds plus crew a fair idea of how best to execute a turn, which will vary depending on conditions.

We should remember that they are busy testing different strategies (eg, a turn in xyz conditions), to see which evaluate the best, and which they can best execute in real time with real people.

IMO.

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Waves won't affect their tacks much, apart from anything, they aren't sailing in big waves.

And current doesn't affect the speed of tacks of them or any other sailing boat. Its just they have moved with the water a bit by the end of the tack (and it can kick up a bit of chop).

None of those factors explain a 100% variation in time to do a tack

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6 minutes ago, enigmatically2 said:

Waves won't affect their tacks much, apart from anything, they aren't sailing in big waves.

And current doesn't affect the speed of tacks of them or any other sailing boat. Its just they have moved with the water a bit by the end of the tack (and it can kick up a bit of chop).

None of those factors explain a 100% variation in time to do a tack

True, in relation to the tack... Do you think they're trying out a wider radius turn?

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43 minutes ago, MaxHugen said:

True, in relation to the tack... Do you think they're trying out a wider radius turn?

It's interesting, but I don't think we'll know much in terms of manouver speed/radius until racing.  

 

I once had the chance to do some two boat testing against a vastly better helm from  another class. We did a lot of tack testing. He spun the boat faster than me, but we both seemed to net zero gain. So I did a day of slow, he went fast, and we were both slower.  Even with a server farm giving you targets, sometimes sailing style still prints through.  The real test would be to put someone elses private boat next to Ineos, and see if Ben spins faster to he can cut off the bacsktay. 

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I still think, in an ideal scenario, the tacks would be as quick as possible. Less time off optimum VMG the better.

  1. But are they limited by the structural loads?
  2. Are they limited by foil stall?
  3. Are they limited by the mechanics of foil and rig movements (how fast are the actuators)
  4. How quickly can the flight controller and main timmer cognitively process what's happening and input commands to control systems
  5. How well can the crew co-ordinate the simultaneous trim / steer / fly inputs at speed?

So, I'd say, from the outside, the less least time from tack to tack (or gybe to gybe) the better. But, there are are plenty or reasons why teams won't be turning so quick and why there might be variations in their turning speed. 

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36 minutes ago, Mozzy Sails said:

I still think, in an ideal scenario, the tacks would be as quick as possible. Less time off optimum VMG the better.

  1. But are they limited by the structural loads?
  2. Are they limited by foil stall?
  3. Are they limited by the mechanics of foil and rig movements (how fast are the actuators)
  4. How quickly can the flight controller and main timmer cognitively process what's happening and input commands to control systems
  5. How well can the crew co-ordinate the simultaneous trim / steer / fly inputs at speed?

So, I'd say, from the outside, the less least time from tack to tack (or gybe to gybe) the better. But, there are are plenty or reasons why teams won't be turning so quick and why there might be variations in their turning speed. 

But as I say I have looked at quite a lot of footage and timed it, and they can do it in 6s (same as NZ) and then they stay dry. So that eliminates 2, 3, 4, 5 as a principle

It is possible they are deliberately slowing it the rest of the time to lessen loads, but I'd be surprised if speed of tacks and gybes was a major factor in any load (or that they hadn't allowed for the faster ones)

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if the narrative is that you are slow and inconsistent, why go out of your way to disprove the notion.

when actual observers, weta, mike and now others are saying that the speed differential that is supposed to exist isnt actually there 

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9 minutes ago, JALhazmat said:

if the narrative is that you are slow and inconsistent, why go out of your way to disprove the notion.

when actual observers, weta, mike and now others are saying that the speed differential that is supposed to exist isnt actually there 

Oh I  am sure that some of the negativity on here is entirely unjustified (and much predicated on bias in any case), but I'd be surprised if the other teams were fooled by anything like that. Although one of the journos did comment that GB were the ones that tended to stay away and looked fast from a distance but then would change when anyone got close, so who knows

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Maybe ride height also matters when tacking because of having less rudder in the water, some of them are pretty narrow down low and may be a ‘load’ limit. 

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1 hour ago, enigmatically2 said:

But as I say I have looked at quite a lot of footage and timed it, and they can do it in 6s (same as NZ) and then they stay dry. So that eliminates 2, 3, 4, 5 as a principle

It is possible they are deliberately slowing it the rest of the time to lessen loads, but I'd be surprised if speed of tacks and gybes was a major factor in any load (or that they hadn't allowed for the faster ones)

well, I would think 3, 4 and 5 can be quite variable. 

I mean, I've done some sweet 5 second tacks in the 800... but they aren't all like that. 

3 is fine, if you pop the foil to correct setting right away, but maybe you can't then micro adjust for variations and that slows things down.

4 again, a fumble of a finger, a wobble on the stick etc and the helm has to slow things down. In the skiff, you don't head up out the gybe if the crew hasn't popped the kite and got hand on the trap.

5 again, if person a is 0.2 seconds off with their button, if spooks person b who is then a further second off and so on. 

None of this is happening in a perfect environment. No two tacks are the same, you will have different entry speed, different wind speed, different wind sheer, even different water density etc... 

No doubt some of the variation in manoeuvre speeds will be down to the context within their training session and goals for the day. But come race day, the least time not on VMG will win out (on the manoeuvre front). I can't imagine a scenario where slower turn rates give a lower VMG loss and I can't imagine teams are aiming to slow down their tacks deliberately. 

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12 minutes ago, Mozzy Sails said:

4 again, a fumble of a finger, a wobble on the stick etc and the helm has to slow things down.

And the guy with the hand-held controller is at the back of the trench, more strongly impacted by the G-forces in a tight turn - can he hold on and operate his iPad at the same time?

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20 minutes ago, weta27 said:

And the guy with the hand-held controller is at the back of the trench, more strongly impacted by the G-forces in a tight turn - can he hold on and operate his iPad at the same time?

Gotta be tough, definitely don't want your fingers to go sliding around the screen or buttons and put both foils up.  Are the controls allowed to have any macro controls or is it all direct input?

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13 hours ago, enigmatically2 said:

Not that much. Boat speed will be high whatever so the rate of turn will be much more consistent than most displacement boats, waves won't be an issue for the conditions these things are racing in, current makes no difference (apart from to waves) and the whilst the timing of the tack may be chosen for a lull for example, the rest should be pretty consistent for a well drilled crew. 

But for whatever reason at the moment it isn't for GB and it shows how well they stay up. They plainly are no mugs so I don't believe it is poor crew-work or training, or even the boat design for that matter, but I can't figure out why it does vary so much

Currents do matter but not in the way you think. I've got a friend working at Tidetech who sent me this image because they have an Auckland tidal model. Apparently the Teams also need tidal current data to accurately work out their boat speed, not just GPS speed. At this level every bit of knowledge and advantage they can get makes a difference. 

2020-12-04_16-14-34.png

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49 minutes ago, Priscilla said:

Tides for the ACWS show dead low or thereabouts.

825592922_ScreenShot2020-12-04at6_34_07PM.thumb.png.92b28cf4cc062f8de9f1b3e16b72e675.png

It's a common misapprehension that the water stops flowing at high or low water., this is a grib shown in Expedition at low water tomorrow, nearly a knot of flood passing North Head but still going out in the main channel. 

LW Auckland 1747 local 5th Dec.jpg

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1 minute ago, Ripple Rider said:

It's a common misapprehension that the water stops flowing at high or low water., this is a grib shown in Expedition at low water tomorrow, nearly a knot of flood passing North Head but still going out in the main channel. 

LW Auckland 1747 local 5th Dec.jpg

Do you have access to an expanded view that shows tidal flow for all the proposed race courses.

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@Priscilla 

Obviously just under North Head is the area for race course C. I will see what I can do regards the other race areas. I will need to contact my Tidetech friend again. 

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Let me re-iterate, I was talking in the context of the time it takes to tack. Current makes no difference to that. Yes current matters to other points of sailing

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3 hours ago, Ripple Rider said:

Currents do matter but not in the way you think. I've got a friend working at Tidetech who sent me this image because they have an Auckland tidal model. Apparently the Teams also need tidal current data to accurately work out their boat speed, not just GPS speed. At this level every bit of knowledge and advantage they can get makes a difference. 

 

Really, they are using tidal data with GPS to give true boatspeed through the water? I find that very surprising. Don't the use sonar for speed? Tidal models are great, but wind and pressure will affect them surely? 

Tide matter less in faster boats as it makes up a smaller proportion of boat speed. True windspeed is much more important.. but off course a 1 knot current will change the true wind speed by 1 knot. 

There a counterintuitive point downwind, when you are going against the current, that you want to be in the strongest current. Because you make more out of the increase in true wind speed than you lose from having more water to sail through to get where you are going. 

However, I suspect that variations in ground windspeed across the course will be greater than the tidal affects on true windspeed. So they'll probably ignore tide and sail to the gusts and shifts. 

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So INEOS have stuck on some mast pods too... just like luna rossa and before them ETNZ...

Plus a big white box on the mast head

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12 minutes ago, Flippin Out said:

Bit of fun at 3.20

Puts the speed of these things into perspective at 8.09

At 3:30, makes me wonder if the mast doubles as a snorkel?

They looked very unstable out there today. Maybe the flight controller had a hangover.

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34 minutes ago, MaxHugen said:

At 3:30, makes me wonder if the mast doubles as a snorkel?

They looked very unstable out there today. Maybe the flight controller had a hangover.

improved a lot when the jib was changed 

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1 hour ago, Flippin Out said:

Bit of fun at 3.20

Puts the speed of these things into perspective at 8.09

That bow shape is clearly pretty darn effective at getting the boat back out of the water though!

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1 hour ago, MaxHugen said:

They looked very unstable out there today.

They had a couple of hiccups, but overall I didn't think they looked too bad. Pretty nice ride height in light to moderate conditions. 

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3 minutes ago, Horn Rock said:

They had a couple of hiccups, but overall I didn't think they looked too bad. Pretty nice ride height in light to moderate conditions. 

I thought they had a bit of trouble with height... seemed to increase/decrease quite often, plus also a few touch downs.  Perhaps it was a little gusty, doesn't take much to change the balance of these boats.

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13 minutes ago, MaxHugen said:

I thought they had a bit of trouble with height... seemed to increase/decrease quite often,

All the boats do a bit of hobby horsing. Some a bit more than others. I thought Ineos looked reasonably dialed in. That big keel of theirs lends itself to some nice end plating if they can be consistent with their flight. 

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49 minutes ago, MaxHugen said:

I thought they had a bit of trouble with height... seemed to increase/decrease quite often, plus also a few touch downs.  Perhaps it was a little gusty, doesn't take much to change the balance of these boats.

In the first bit where they are going up and down a bit it looks like it may have been because of  headers. It looks to me like the front of the jib backs twice causing the instability. 

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On 12/2/2020 at 11:21 AM, enigmatically2 said:

ery different beasts though, I'm not convinced that the other boats are losing much momentum on the slower turns this time around. A bit obviously, but how it sits in the trade-off from VMG gained I am not sure

Does anyone know if they are allowed Autopilots on the rudder?

I suspect the other limiting factor is the strength of the boat, from some of the interviews I have heard they are already pulling relatively high G loads through the turns.  

 

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17 minutes ago, Laurence said:

Does anyone know if they are allowed Autopilots on the rudder?

No auto pilots anywhere.

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On 12/3/2020 at 3:40 AM, enigmatically2 said:

But there are losses from a quicker turn too Mozzi, more rudder angle and the main foils are less head on so will be less efficient. Part of my doubt is that I can't see anything stopping all the teams turning more quickly. The headsails are very quick, the foil movements are quick. LR doesn't even have to change sides, so why not speed it up?

The opposition never got to the same level in Bermuda 

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43 minutes ago, fish7yu said:

 

I don't know what others think but I found much of the video a bit worrying.  Just wondering about the type and sensitivity of control systems they have.  It wasn't the big oopsies that I found particularly interesting but towards the end of the video,  the "porpoising" or over-correcting which lead to the final big dump.  Compared with the stability of ETNZ,  control doesn't look anywhere near as refined.

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51 minutes ago, GeeJay said:

I don't know what others think but I found much of the video a bit worrying.  Just wondering about the type and sensitivity of control systems they have.  It wasn't the big oopsies that I found particularly interesting but towards the end of the video,  the "porpoising" or over-correcting which lead to the final big dump.  Compared with the stability of ETNZ,  control doesn't look anywhere near as refined.

Yup. After watching LR undertaking similar manoeuvres on the same day at the same place Mr Ratcliffe might be asking for his money back very soon. Lets hope not!

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7 hours ago, GeeJay said:

I don't know what others think but I found much of the video a bit worrying.  Just wondering about the type and sensitivity of control systems they have.  It wasn't the big oopsies that I found particularly interesting but towards the end of the video,  the "porpoising" or over-correcting which lead to the final big dump.  Compared with the stability of ETNZ,  control doesn't look anywhere near as refined.

That splash down is the same as the airflow vid from the other day just shot from a different angle unless they are passing the same ferry in the same location and getting out of sync with the wake in the same way. 

interestingly though the rest of it looks much smoother than the air flow vid.

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2 minutes ago, JALhazmat said:

That splash down is the same as the airflow vid from the other day just shot from a different angle unless they are passing the same ferry in the same location and getting out of sync with the wake in the same way. 

interestingly though the rest of it looks much smoother than the air flow vid.

I didn't see the Airflow vid but what was of particular interest was the bow going down and then raising and repeating the cycle on an almost consistent basis.  I'm  curious about the root cause as the other competitors appear to be more stable through ferry wakes, unusual wave patterns etc. Must keep an eye on them.

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They dumped power reducing undue loadings. Takes 12 hours to prep the boat each time they go out and they won't want any needless maintenance and associated costs, not to mention time.

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On 12/4/2020 at 4:41 AM, Flippin Out said:

Bit of fun at 3.20

Puts the speed of these things into perspective at 8.09

Who says that Britannia is not faster than other sailboats.....  

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11 hours ago, barfy said:

That is seriously below sea level..like a reef sucking break ala teahupoo

Teahupoo

Tahiti

 

 

BT_20150722_Teahupoo-Big_0693-XL.jpg

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7 minutes ago, Barnyb said:

Teahupoo

Tahiti

I motored in through that pass with 7m west swell that was too knarl for any surfers and was seriously feeling the bottom in the pass. Terrifying to be so close to all that power in a fragile boat.

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