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martin 'hoff

Nacra 15 FCS for fun

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In a moment either deeply wise or stupid, I made a move on a N15 FCS that was available ex-demo for a price I liked.

There's a separate thread where I posted about my adventures on a red Whisper. That boat is now for sale (with brand new sails and various upgrades https://sailinganarchy.com/advert/whiteformula-whisper-foiling-catamaran/ ) . And we're getting onto the new challenge.

From what I see, there's a handful of non-olympic pathway sailors sailing N15s; some in the "Nacra 15 FCS One" configuration (optimized for soloing – has a decksweeper for lower CoE, and a different kite halyard setup), some in the standard config. So I guess that's my track, I'm too grown for the N15 competitions.

Anyway, are there any N15 sailors reading this forum? It'd be great to trade notes.

At this point, we're only getting started and finding that the boat can be pretty powered up. Intent is to sail it for fun, occasional local races, and perhaps try to pace the proper N15/N17 fleets when they are in town. Soloing (~80Kg), two up with my 10yo kid, or just 2 adults.

  • The manual is a bit skimpy on rigging setup. Are there better descriptions of rigging setup, and variants? I'm keen to see how the halyard runs in the One configuration. Keen to see how the cunningham is setup – apparently on N17 the skipper actively the cunningham to depower.
  • What foil rakes are people using? We're on the standard rudder rake, and between 2 and 3 for initial skimming/foiling.
  • "Walk the boat" technique – we used to walk the boat on the Whisper to get it flying and then to help control flight. On this boat, we need to up that game 100x, any tips on technique welcome. 
  • Protective gear? (ie: kevlar wetsuits for kids?)

If you are wondering, the boat is a complete hoot, and can be a handful. Took the boat out on its second foiling outing with 12kt gusting 16kt and a bit of chop, and that was premature. I expected as much, and took an adult instead of the kid. In breeze, boat is pretty powered up and we flew out of waves (stuck the bows a bit, etc).

 

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One more question: I know I've seen a variant of the N17 FCS setup, with lines running outside of the main crossbeam, a knot on the line, and a "rake grading" sticker, so you could look at the crossbeam and know what rake each foil has. 

Cannot recall where I saw this -- may have been on the boatpark here in Miami. 

Does anyone have a diagram of how that layout runs? 

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Ok, so there's a video series by Thomas Zajac – shot in Montevideo – which has elements I don't enjoy (Thomas appears rather blase about people's safety) but has a ton of onboard headcam footage, showing Thomas' setup up-close.

https://www.youtube.com/watch?v=PF6tSn_t2aw

At 9:26 you can see a good clear shot of the rake gauge setup. Cunningham line goes to the crew's trapeze. Jibsheet goes to shouds. 

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Congrats on the new boat!

Not sure how much is out there regarding rigging for these boats if you don’t talk to the owners first hand. The DNA A-Cat has similar board markings rigged as part of their system. I believe it is simply a knot tied into the board control line. 
 

This video just came across my desk and may help: 

 

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10 minutes ago, samc99us said:

Congrats on the new boat!

Not sure how much is out there regarding rigging for these boats if you don’t talk to the owners first hand. The DNA A-Cat has similar board markings rigged as part of their system. I believe it is simply a knot tied into the board control line. 
 

This video just came across my desk and may help: 

 

Thank you @samc99us! - so this is a bit more complicated! :-) interesting. Instead of running takeups under the tramp, or inside the rear crossbeam, they go alongside the rear crossbeam -- that's... unexpected. 

I'm intrigued by the markings and numbers on the boom. Can't see what they are measuring there. Also, the cunningham trim markers have a much narrower band than Zajac's. 

The foil rake trim markers are doubled up -- both foils are visible on both sides of the crossbeam. 

Foil rake lines offering a single line but having it bi-directional is definitely an improvement. 

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The boom markings are outhaul, almost guaranteed. The back set is for the skipper to quickly visualize, front set are for the crew to fine tune as they have a 2:1 lead. 

I am also surprised that everything is pretty much above the tramp with a few exceptions. The aero drag delta for that is minuscule compared with the penalty for tripping over a line!

Do take note of the heavy use of ceramics and stainless blocks. I have a great ceramic mainsheet option that isn’t nearly as pricey as the Harken; the downside is the ratchet setup relies on an external block, easily managed on an A with center sheeting, a bit more trouble for rear sheeted boats but doable.

 

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10 hours ago, samc99us said:

Turns out the forward boom markings are mainsheet trim indicators.

How does that work?...

The loads on N15 seem to be lower. More run-of-the-mill blocks. Also, other N17s in videos have shockblocks/sheaves and less sophisticated stuff. That's a Harken promo video, so every chance to use a cool block has been taken :-)

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Sneaked a short outing today. Smooth sailing with Alessandro at the helm. 10kt gusting 14kt. 

Our short outings are on a narrow spot so no chance for a good deep spinnaker run. The kite power on a reach is hard to handle (at least now, for us) and I don't think we had that situation under control. We're using to having a footstrap for the helm; without it we felt vulnerable. 

Rake 2-3. Main started out depowered, but as we found our stride I powered it up. In these winds upwind foiling vs non-foiling difference was 30 degrees. On our first outing with more wind, it looked like we could do pretty nicely foiling upwind -- footing perhaps 10 degrees.

 

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Gear -- aiming to get

  • footstraps -- 1 pair initially, perhaps a second pair later
  • helmets
  • kevlar gloves (as per the WS report from Bora's accident)
  • kevlar wetsuit

(I recently took an acquaintance out sailing on a different foiler, and in a moment of distraction he got cut. This boat's foils are "inboard" which is really good, but they are sharp...)

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On 10/6/2020 at 12:51 PM, samc99us said:

Do take note of the heavy use of ceramics and stainless blocks. I have a great ceramic mainsheet option that isn’t nearly as pricey as the Harken; the downside is the ratchet setup relies on an external block, easily managed on an A with center sheeting, a bit more trouble for rear sheeted boats but doable.

Apologies for the thread hijack, but I'm in the process of going DS on my A.  What is this ceramic mainsheet option of which you speak?

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2 hours ago, Phat Buoy said:

Apologies for the thread hijack, but I'm in the process of going DS on my A.  What is this ceramic mainsheet option of which you speak?

High end blocks for 10:1 and higher purchases, used on N17. The mainsheet itself is dyneema core...

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Martin,

  Yes and no. Harken have their GP mainsheet system, specifically designed for the Nacra 17 and to some extent the F18. It is a nice solution with integrated auto ratchet. I am working with another company on a simpler, less expensive system. The cascade is more like the 8:1 and 10:1 systems of old, and the ratchet is external. We have it on one A-Cat here and it is working great! Phat Buoy, PM sent.

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Martin

Congrats on the new boat. Settings are one thing, but as you have discovered and implied, sailing technique is where it is at and there are some things that aren't so obvious. What is obvious is that there is no wand, which used to help by managing flight height changes with a given set of settings, so that for any crew weight position and sail time, it make adjustments to the ride height when it changed so you didn't need to. Now, everything is up to you. This means you are constantly moving, constantly sheeting and constantly steering.

 

The key to this game is to stop thinking about trimming your sails in a conventional way. The sails are your height control. Load the sails (pull in) and this loads the foils and the boat reduces ride height. Ease the sails and the foils unload and ride height increases. That's the basics. So consider sailing with the kite up. Should you be sheeting for proper airflow and power, or should you be sheeting to control the amount of load on the foils and therefore the ride height. The simple answer is the latter, while the long answer is that it is the latter combined with walking the gunwale and steering. But that's getting into advanced territory. To start with, practice ride height control through sail loading (assuming you are standing in about the right place). Once you get the hang of that, combine it with walking the side so that you can reduce the amount of sheeting a bit and maintain as good flow over all the sails as possible and finally, combine it with steering.

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@SimonN - spot on. Yes, this is a bit more like an a-cat that we should actively use pressure on the rig to control ride height. We were already doing some of that on the Whisper, so not entirely new. It's also fairly different in particular in the downwinds – you can't play the kite as you play the main, and the heat up/soak dynamic also plays into the ride height. 

It's a strange game I'm still wrapping my head around. When you bear away with speed, that pushes the boat down (more pressure from the rig, down on the foils), and the bow a bit down (more leverage forward top of mast) and depending where you are on the wave sequence, if you walk astern on the boat you might punch through the next wave top, or dig the bows and go for a spectacular flight.

If you're about to plant it in a trough, what's the maneuver? Here's my current thinking: head up (heat up) will increase speed, reduce pressure down and leverage from top of mast will move from forward - bow down - to heeling. So the boat will pop up, point bow up, and heel. Uncontrolled/abrupt, this will result in the typical "rearing horse" moment followed by stalling the foils and splashdown. But if the helm heads up subtly and the crew walks forward and stretches out (for leverage on the wire)... well, you gotta get the timing and dynamics right but it should: increase speed, reduce downward pressure (boat rides a bit higher), crew forward drives counterbalances nose up-tendency, crew out (and ease of main?) counteracts heeling, and finally (assuming waves aligned with the wind) the hotter angle means a longer wave length so better chance to save it from a nosedive.

Is this reasonable? Other takes on the downwind sequence?

We took part in a long distance race yesterday (mixed fleet). We did really well while mast-up ;-) -- on handicap time, roughly speaking we lost by the time spent capsized. Footing slightly, we'd do stretches of ~10-12kt upwind. We only did about half of the downwind leg with good speed – we're still figuring this puppy out – but when we did, we we smoking. Big swells and long distance so limited foiling. 

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Martin - when you guys had it going Saturday you were seriously moving! Can’t wait to see what the boat is like fully dialed in. 

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1 hour ago, JoeyG said:

Martin - when you guys had it going Saturday you were seriously moving! Can’t wait to see what the boat is like fully dialed in. 

Thank you! You were in the coirsair that finished first, right? Good stuff! 

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22 hours ago, martin 'hoff said:

Thank you! You were in the coirsair that finished first, right? Good stuff! 

Correct 

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We thought we'd get 10kt but it was blowing 6kt gusting 8-9kt. We'd get it on the foils but it'd be tricky to avoid stalling the mainsail. Still... a ton of fun!

 

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We expected 10-12kt, but we found 12-15kt and at times 15 gusting 20kt. All normal for Biscayne Bay, but we're only starting to get the hang of it. So we focused on having a relatively easy ride, depowering plenty, focus on maintaining control. We aren't hardened enough yet to milk 15-gusting-20 for angles and speed...

 

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Hey Martin - loving these videos of your adventures!!  My 16 year old has just got a Nacra 15 FCS sorted here in Sydney, and has had one glorious morning out testing it and learning to fly!!  He's been in the N15 for 3 years now, and the FCS takes it to the next level. He and his crew were so pumped after their first foiling run - this after having a UFO for the last couple of years as well.

We are just getting regattas started up again in Sydney so he will spend more time in C foil mode, but come summer holidays I imagine most days he and his crew will be chasing flight time!!

All the best!

Chris

 

 

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@Stanno - love it! We should trade gpx files and tuning details.

Minor question: Do you have diagrams of how the downhaul gets tied/attached at the grommet of the sail? I have the 2 lines with balls, and I have rigged something but I suspect it's not quite right. The way I have it, "max outhaul" doesn't feel flat enough, or maxed out enough. 

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Hi Martin

I'll get some photos of the downhauls we use on the various Nacra 15's we have at the Club .... and yes to the other when the kids finish exams!!

 

Cheers

Chris

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Somebody has been spending lots of money with Thorpie! At least he know what he is doing with foilers, at least in the workshop. Not sure if he has recovered from his last sail on his foiling A:D

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22 minutes ago, SimonN said:

Somebody has been spending lots of money with Thorpie! At least he know what he is doing with foilers, at least in the workshop. Not sure if he has recovered from his last sail on his foiling A:D

Money spent with Thorpie in the workshop is ALWAYS money well spent!!  Even more so was the time he kindly spent with my son showing how to set the boat up, the disciplines needed to keep it in good nick, and , no doubt courtesy of that ride on the A, how to survive the early days of foiling!!! ;-)

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Hi Martin

Here are some shots of my son's Nacra 15 downhaul set up for his Nacra 15... they've dispensed with the balls and gone with soft shackles onto the blocks ....

The kids have been mixing their time between the Cfoiler and the FCS foiler over the last weeks, along with school exams - its been quite awesome to see them in full flight!!

Hope the pics help....

Cheers

Chris

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Oh cool. Thank you @Stanno. I have put soft shackles on the blocks, and put them over the balls. I'll take pics as well.

Is that orange strop adjustable length in any way? 

We have 2 problems: 

- it's a pita to set up, because you're fighting the bungees

- it runs out of length and power when it's windy; this mast is stiff!

on other foilers with CF mast, when it's windy I crank the cunningham hard to switch the sail from depth to flat/twist. I don't think I have the power, "travel length" needed, unless I put an adjustable line in there, and maybe add a bit of purchase (or, hit the gym!)

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Detail of a messy run we captured on video. I believe an earlier run in the day had been really smooth, but alas, no video of it. 

 

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On 11/19/2020 at 5:40 AM, martin 'hoff said:

Oh cool. Thank you @Stanno. I have put soft shackles on the blocks, and put them over the balls. I'll take pics as well.

Is that orange strop adjustable length in any way? 

We have 2 problems: 

- it's a pita to set up, because you're fighting the bungees

- it runs out of length and power when it's windy; this mast is stiff!

on other foilers with CF mast, when it's windy I crank the cunningham hard to switch the sail from depth to flat/twist. I don't think I have the power, "travel length" needed, unless I put an adjustable line in there, and maybe add a bit of purchase (or, hit the gym!)

Martin,

Probably doesn't matter to you right now, but the class rules for the 15s are written so that the cunno is "fixed" at the eyelet in the sail. So the 2 ball system is used to achieve this. To get extra purchase (not class legal,) you can just change the setup to allow the rope through the eyelet to run, as a continuous piece between the cunno blocks. 

Re: fighting the bungee, you can run a continuous system inside the front beam which works really well, common on a lot of other cats. happy to describe that if you are interested, its inferred in the rules for the 15 where they specify the pully size and bungee diameter.

Yes the mast is stiff, probably looking for on the high side of 50mm measurement at the spreaders on a windy day. YMMV

Cheers

 

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4 hours ago, Flags said:

So the 2 ball system is used to achieve this. To get extra purchase (not class legal,)

Thanks! Is there a picture or a diagram showing how this goes?

I'll be happy to try the class legal version. Right now I have an awkward setup that is neither class legal nor practical.

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Martin, you should consider going to Clearwater and spend a day or two with Robbie Daniel. He has coached N15 from its inception and currently coaches youth at Sarasota. He also coaches Olympic hopefuls on N17 and sails a foiling A cat. Might help with rigging and technique. 
Also, is your kite the standard or does the foiling kit come with a flatter kite?  

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23 hours ago, martin 'hoff said:

Thanks! Is there a picture or a diagram showing how this goes?

I'll be happy to try the class legal version. Right now I have an awkward setup that is neither class legal nor practical.

Oh so you have 2 bits of rope with balls on them, you make a loop in one rope and push the loop through the eyelet, and put the other ball up through the loop you made. Pull tight. will try and take a photo tomorrow for you.

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1 hour ago, Flags said:

Oh so you have 2 bits of rope with balls on them, you make a loop in one rope and push the loop through the eyelet, and put the other ball up through the loop you made. Pull tight. will try and take a photo tomorrow for you.

Thank you. Ok, so if I'm understanding right each rope has the other end tied in a bowline to the little 3x block. Is that right?

Thinking about it, it seems quite a sub-par setup. Tighten it up on port tack, you can't ease it at all on stbd tack. Blergh. With the exact same kit, you could use a line twice the length, one end tied to the block, the other end with a soft shackle or ball, and "run" it through the grommet... use the grommet as a low friction ring.

Is there a gross tune to this setup? On a windy day, I want to shorten this strop to get more range at the tighter end...

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5 hours ago, martin 'hoff said:

Thank you. Ok, so if I'm understanding right each rope has the other end tied in a bowline to the little 3x block. Is that right?

Thinking about it, it seems quite a sub-par setup. Tighten it up on port tack, you can't ease it at all on stbd tack. Blergh. With the exact same kit, you could use a line twice the length, one end tied to the block, the other end with a soft shackle or ball, and "run" it through the grommet... use the grommet as a low friction ring.

Is there a gross tune to this setup? On a windy day, I want to shorten this strop to get more range at the tighter end...

Your understanding is correct... Yes, and so is the mod you propose which is what I described above, but the association voted it down and specifically excluded it. That said if you are not racing other 15s (foilers) I don't see that it matters. Certainly plenty of 15 sailors run what you propose, just not at class events.

FWIW I have never heard the kids complain about needing gross vs fine adjustments, nor running out of adjustment. I will ask.

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Martin, Tie a bowline to the top of each block with the stopper ball at the end. With the longer rope make a loop, pass it through the grommet, pass the ball on the shorter rope through the grommet, and it is secured. I've never heard a kid complain about needing more downhaul on the 15. The mast could take a 16:1 but you'd still need to be careful and if it broke it wouldn't be warrantied. The sail can get really flat with the existing setup.

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1 hour ago, Flags said:

FWIW I have never heard the kids complain about needing gross vs fine adjustments, nor running out of adjustment. I will ask.

The way I'm running it currently, it has half the adjustment travel (and half the load); so if I change to the class-approved approach, I expect I'll get the full range.

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Cool! Thanks for the pics @Flags! I think I'll use a short strop to get the class legal style setup, but make it slightly easier to set up. I want the full travel so I can depower.

I will be moving the crew trapeze to the shrouds. On the crossbeam, it conflicts with the kite, and I step out of the boat usually at the shrouds (and trap from well aft). Should simplify main and kite sheet handling.

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2 hours ago, martin 'hoff said:

Cool! Thanks for the pics @Flags! I think I'll use a short strop to get the class legal style setup, but make it slightly easier to set up. I want the full travel so I can depower.

I will be moving the crew trapeze to the shrouds. On the crossbeam, it conflicts with the kite, and I step out of the boat usually at the shrouds (and trap from well aft). Should simplify main and kite sheet handling.

Happy to share more pics, interestingly it looks like the class are moving to allow both systems next year.

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25 minutes ago, Flags said:

Happy to share more pics, interestingly it looks like the class are moving to allow both systems next year.

That's cool. I had a chat with a n17 sailor and discussed a bit how the n17 has it. I might copy that setup somewhat. 

A finger-trap adjustable strop in your non-class-legal version would achieve both range and purchase.

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1 hour ago, martin 'hoff said:

That's cool. I had a chat with a n17 sailor and discussed a bit how the n17 has it. I might copy that setup somewhat. 

A finger-trap adjustable strop in your non-class-legal version would achieve both range and purchase.

Back to the americas cup :)

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@Stanno @Flags – we did a mixed fleet long distance race last Saturday, using C boards and regular rudders because the course ran over sandbars and shallows. We hadn't sailed with the C boards before.

We got there early, and had a practice / course conditions exploration run. We found perhaps 10kt of wind, it was an upwind run, not too tight, and once we found the groove we were doing 12-14kts. 

When the race started, about 1hr later, the wind had dropped to ~8kt and we just could not make it go fast. We were in the same spot, same angles, 2kt less TWS, and we were doing6-7kt boatspeed.

Looks like there's a big hump with the C foils. Does that ring true? Or maybe we couldn't find the right configuration for the lighter air? 

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14 hours ago, martin 'hoff said:

@Stanno @Flags – we did a mixed fleet long distance race last Saturday, using C boards and regular rudders because the course ran over sandbars and shallows. We hadn't sailed with the C boards before.

We got there early, and had a practice / course conditions exploration run. We found perhaps 10kt of wind, it was an upwind run, not too tight, and once we found the groove we were doing 12-14kts. 

When the race started, about 1hr later, the wind had dropped to ~8kt and we just could not make it go fast. We were in the same spot, same angles, 2kt less TWS, and we were doing6-7kt boatspeed.

Looks like there's a big hump with the C foils. Does that ring true? Or maybe we couldn't find the right configuration for the lighter air? 

It might be a power to weight ratio thing. That happens in C board A Cats versus straight board boats. At or below about 7 knots the straight boarders rule but as soon as the wind increases the greater flow over the C boards gives lift and they take off. The extra weight of the Nacra would mean that performance payoff occurs a bit higher in the wind range. 

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On 12/21/2020 at 9:08 AM, martin 'hoff said:

@Stanno @Flags – we did a mixed fleet long distance race last Saturday, using C boards and regular rudders because the course ran over sandbars and shallows. We hadn't sailed with the C boards before.

We got there early, and had a practice / course conditions exploration run. We found perhaps 10kt of wind, it was an upwind run, not too tight, and once we found the groove we were doing 12-14kts. 

When the race started, about 1hr later, the wind had dropped to ~8kt and we just could not make it go fast. We were in the same spot, same angles, 2kt less TWS, and we were doing6-7kt boatspeed.

Looks like there's a big hump with the C foils. Does that ring true? Or maybe we couldn't find the right configuration for the lighter air? 

 

12 hours ago, WetnWild said:

It might be a power to weight ratio thing. That happens in C board A Cats versus straight board boats. At or below about 7 knots the straight boarders rule but as soon as the wind increases the greater flow over the C boards gives lift and they take off. The extra weight of the Nacra would mean that performance payoff occurs a bit higher in the wind range. 

In WnW's example, you have two boats that are the same except for the foils, and I would venture to say the C-board boats suffer more drag from the rudder winglets they normally are equipped with than the c-boards, but both can be sailed competitively and in the upper wind ranges the C-boards certainly perform better. The latest eXploder and DNA C-boards are also nicely shaped with good lift and low drag, I would argue they are higher performance than the Nacra boards but that is expected in a development class.

The biggest issue with the N15 as you experienced isn't the foil package, but the lack of horsepower. That is a rig size issue, and boat weight issue, resulting a lower horspeower to weight ratio multihull that is great for youth sailing, but for handicap distance racing it isn't ideal. The boat really needs 15kts of breeze to get going.

 

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2 hours ago, F18 Sailor said:

The biggest issue with the N15 as you experienced isn't the foil package, but the lack of horsepower. That is a rig size issue, and boat weight issue, resulting a lower horspeower to weight ratio multihull that is great for youth sailing, but for handicap distance racing it isn't ideal. The boat really needs 15kts of breeze to get going.  

There's some truth to that horsepower comment. I was sailing against Viper F16, N6.0,  etc.

At the same time with the foiling kit, once there's ~9kt steady TWS, I can get it on the foils, the boat speeds up significantly and I have to flatten the main quick to reduce drag. There is a speed hump, definitely.

For whatever reason, I expected the C foil package to have a less pronounced a hump, and to have the hump at a much lower TWS. This was on an upwind/slightly footing course, and we saw a hump (say, 7->13kt boatspeed) happening at around 10kt TWS. This is not that different from the Z+L foil package upwind. 

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It's just small.  This will hurt you in medium winds the most.  Once you get to the windy stuff, the sailor with the biggest balls wins.  Your boat was designed as a youth boat, so to not be overpowered for a 120kg all up crew, think you'll always struggle to hold on to even well sailed F16's, and F18's and A cats etc should be lapping you on a 4 lap race, in double handed mode, in less than 15 knots of wind.  Would love to be proven wrong, 18 footers are a pain in the arse ashore, if a 15 footer could do what an 18 footer could do, life would be perfect.

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I think all of the above comments re power are correct .... also while the N15 jib isn't huge, it does do a lot of shaping of flow onto the main, and by sailing without it you aren't in the design mode the two up N15 with C boards was designed for ... I guess you just found where that performance issue starts to bite!!

Loving the videos - the grin on your son's face sums up why the N15 is one of the great youth boats going around ... and sailing with dad is pretty good too!

Have a great Christmas period, stay safe and keep sending it!

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5 hours ago, Stanno said:

I think all of the above comments re power are correct .... also while the N15 jib isn't huge, it does do a lot of shaping of flow onto the main, and by sailing without it you aren't in the design mode the two up N15 with C boards was designed for ... I guess you just found where that performance issue starts to bite!!

Loving the videos - the grin on your son's face sums up why the N15 is one of the great youth boats going around ... and sailing with dad is pretty good too!

Have a great Christmas period, stay safe and keep sending it!

Thanks for the comments, and hoping you ahve a great xmas as well.

I generally agree, but I'll note, I'm always using the jib; I'm a bit confused by your "sailing without it" comment.

(Might sail without jib when I try soloing the N15, but that hasn't happened yet.)

 

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How not to do it. Blowing 17-24kt, helm is nursing a knee injury so he couldn't get on the wire, or much hiking either. Even so, getting the hang of controlling the beast. 

On the other side of the causeway, a fleet of optis was racing, showing who's boss :-)

 

 

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A couple of days later, slightly lighter winds – 15-20kt and a bit more control. 

 

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Sorry martin re the jib - I went back and rewatched the videos and got my perspectives sorted!!!

Kids have spent the weekend blatting around on the foils ... Sunday was 8-12 knots and they got some good air time...  they played around with the foil angles and got to know their boat a bit better .... now need to think about sail trim and flattening off the main ...

 

These boats are simply fantastic!!

 

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That looks great! Also, impressive flat water venue.

I'm mulling some tweaks to make the cunningham more easily adjustable on the fly. You want power to take off, and then you want to flatten it.

In gusty conditions, I'd kill for a tapered cf mast that gives some gust response.

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@Stanno are they trimming the cunningham actively once they get foiling? I find that workign the cunningham until I find 3 positions (for the conditions):

  • the right power to pop out (deep
  • the right power to sail upwind (flatter)
  • right power to sail downwind (deep-ish unless overpowered)

In particular upwind, the right cunningham and traveler is where the mainsheet trim is just a few clicks on the ratchet.

What's killing me is that the cunningham is too loaded to actively trim/ease.

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Kids had another great afternoon out on the harbour yesterday, and a seriously good session on their C-foiler earlier in the week with their coach Paul  ...

They did a lot of work on their cunno settings on both boats (and actually cranked the bloody thing on properly!!), and explored ways to make the cunno more accessible to them when double stringing.  Some ideas include taking the line out to the trap of the crew with a dyneema strop - working on this idea and need to sit down with the rules to check it is ok!!  Not that it will make the cunno easier to pull, just put it to hand while out on the wire!! Will send pics when we settle on a model ....

Also used the headset helmets with the kids for the first time after they used them with Paul earlier in the week  ... was fascinating to hear the kids chatter, laughter and really good exchanges as they were preparing to foil and in flight.  Was also handy to be able to be a second set of eyes and have instantaneous continuous comms with them with over traffic in the Bay!  A really powerful coaching and safety tool and one will be using in training going forward!

 

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Good stuff @Stanno!

Yeah cunningham is key. Power to take off,flatten once on the foils - more upwind, a bit more sail depth downwind.

I'm going to move the cunningham take-ups to the main crossbeam, and have a strop that clips to the crew trapeze to "call" both cunningham and jib sheet. I spied such a setup in a competitive N17.

Have you found a way to make the cunningham run better? That's a problem for us now.

For comms, what kit are you using? I've used the bbtalking bluetooth gear (borrowed) and it's great but damned expensive! 

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