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Team_GBR

Foiling Nacra 17 - Yet another World Sailing Disaster?

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The new foiling Nacra 17's are at last up and racing at the Europeans. The first batch were eventually delivered, late, which was no surprise. I am hearing some pretty disturbing things. They have a non foiling, C foil at the Europeans as well, so we can see the old and new side by side and the comparison isn't exactly favourable. Looks like the old boat is faster in most conditions and that the foiler isn't as nice a boat to sail. There are a number of reasons. The new boat is now 20kgs heavier as they have tried to make the boat bomb proof after the boat issues of the first olympic cycle and the foils being made super heavy to eliminate all chance of breakage. The extra weight makes the boat feel really sluggish. The other issue is that it seems like the foil design is poor. It works OK in flat water, but even then, there is a problem with uncontrollable and unpredictable ventilation that nobody has got to the bottom of. I don't believe it is leading to capsizes, but the sudden drop from foiling to floating isn't good. The boat doesn't foil upwind in waves because the handling is too unpredictable. I don't believe that this is due to lack of experience on the boats, because some of the teams have been practising on A's and say it is a foil design issue. The foils are too big, have the wrong profile and the section isn't great. Because the foils are so big, they are very draggy which is why they are slower upwind than the old boats.

The suggestion is that (yet again) the boats have been rushed to market without enough development. It is rather disappointing because the Nacra sailors have had a bad enough time of it and deserved a properly developed boat. At least it seems that for this cycle, the boats won't fall apart and at least it is the same for everybody. They cannot change it for this cycle, but the smart money is on a new foil package after 2020. 

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I had heard that the N17 was rather easy to foil and wasn't that quick. Interesting about ventilation. I heard that they guys doing the A Class foil development found this with some foils and that it only took a fairly small change to the foil to turn a good foil into a dog. It wasn't clear from initial analysis which foils would ventilate, so there must be pretty fine margins for error. It also seems that you need to test in a wide range of conditions (obvious when you say it!) because a foil that is good in flat water might not work in waves. The challenge is that there aren't that many sailors who have the experience to sail well in all conditions. I get ventilation on my A's main foils (Z10) because sometimes I put too much lift in the foils downwind, which happens after I have been going for upwind foiling which seems like it needs more lift than downwind and I forget to change it before heading down.

This probably also explains the often quoted statement from M&M that V foils are faster than Z foils. Of course shitty Z foils will be slower.

It's such a shame if the N17 foils haven't been developed enough but it wouldn't surprise me seeing how long it has teaken to get the A Class foils good.

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Is some of this not okay? Even if the boat is a big sluggish, everyone is in the same boat! The ventilation is annoying but they could probably swap in new boards to the whole fleet now, but does it matter? Just one more performance issue for the fleet to manage. The foiling gybes and hoists look epic on camera which is what sailing needs to sell. 20kg of weight increase sucks but its better than breaking boards and boats, and the loads on a doublehanded foiler being pushed at the Olympic level are simply immense. I think Nacra did a pretty reasonable job considering that, and given the very tight deadlines they were handed. Keep in mind they also built a full fleet of N15's at the same time they were getting the Mk. 2's out the door.

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Except of course Nacra did close to nothing.  M&M did the design work and Element 6 built the boats.  In the modern production cat world the "manufactures" role appears to be mainly making excuses when let down by suppliers and applying stickers.

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I did hear a rumour that one front of fleet sailor had predicted the foils were going to be a nightmare and gave up the class.

The trouble with foils that don't work very well is that an awful lot of time effort and money will be spent on working out ways to circumvent the rules to make 'em work better, and the Nations that do the best job making the boats work will get the medals.

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I don't know what to really think about this. Some of the sailors seem to be pretty unhappy about the situation but that could be intolerance after the debacle of the previous version of the boat. I think what has highlighted the "problem" is that they are sailing with the old C foil boats and therefore direct comparisons are being made. I think the pure speed issue is nothing to worry about, but the C foil boat was a pig and I had hoped that this boat would be properly sorted. The question is why the foils weren't properly developed and there are a number of possibilities. Was it a case of not enough time to test in all conditions? Did the right people get to do the testing? There really aren't that many people around who have the foiling experience to do that sort of development testing and know whether it is the boat or the sailor when things go wrong. How much experience did the design team have with Z foils and was that a factor.

Is it too late and is there the will to improve the foils? Who knows.

2 hours ago, JimC said:

I did hear a rumour that one front of fleet sailor had predicted the foils were going to be a nightmare and gave up the class.

Anybody who quit the class based on thinking it was going to be a nightmare was an idiot. Done right, the boat should be awesome.

2 hours ago, JimC said:

The trouble with foils that don't work very well is that an awful lot of time effort and money will be spent on working out ways to circumvent the rules to make 'em work better, and the Nations that do the best job making the boats work will get the medals.

I don't see this as an issue at all. The rules are pretty tight. The only thing you can play with is foil finish in order to help prevent ventilation. This is already well understood for other foiling boats including Moths and AC cats. I hear that teams have been seen spending lots of time on foil preparation and I cannot believe they all don't know what they are doing.

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i suspect what you're actually seeing with the foils is a gap between the carefully crafted prototypes and the mass produced reality. 

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9 hours ago, samc99us said:

The foiling gybes and hoists look epic on camera which is what sailing needs to sell

Olympic sailing hadn't improved its "sell" in terms of ratings at all since they brought in 49ers, kite-carrying cats, hybrid windsurfers, match racing and all the other stuff that was supposedly going to hook viewers. If skiffs, Tornadoes with kites, match racing and shorter windsurfers didn't sell then why will foiling cats?  The top rating Olympic sports are people running, doing gymnastics and swimming in a straight line at 4 knots.

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2 hours ago, Team_GBR said:

 

Anybody who quit the class based on thinking it was going to be a nightmare was an idiot. Done right, the boat should be awesome.

 

Maybe the "idiots" foresaw the sort of issues you highlighted in your first post, which given the history is not surprising?

Don't quote me, but I seem to recall people saying that ISAF should to rush to get the boats fully foiling. Sometimes they are damned no matter what they do.

 

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7 hours ago, Team_GBR said:

 Done right, the boat should be awesome.

But your OP seems to suggest you don't think its been done right.

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From what I have heard the elite sailors will have a clear lead over the great sailors and part of that will be knowing when to foil upwind. The boat is sliding to leeward foiling but going faster than a C board but if you get on the wrong side of a shift you are spat out the back, they all have to learn how to adjust the foil pitch for the conditions. They are going to be exciting boats to watch in the Olympics so a terrific choice for what they are produced for. I'm loving watching the footage of kids racing the Nacra 15's and can't wait to see more of these 17's

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I suspect there is a large contingent of unhappy sailors; those who made the very unstable C-board boats work, and those that don't have the foiling expertise of some in the class (Bora, Chris Rashley). These guys sail A's and were involved with the development, so I have a hard time believing they made a giant mistake with the main foils.

One should also note that the fleet was split pretty close on votes, something like 48% against foiling. Many folks would have been happy with t-foil rudders and the C-boards, they would buy newer beefed up versions but keep their older boats for training. Also, its not like these guys weren't messing with the foils to begin with, prepping them, packing the trunks to get the right toe-in/toe-out, and in the case of the french moving the trunks.

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9 hours ago, The Jay said:

Olympic sailing hadn't improved its "sell" in terms of ratings at all since they brought in 49ers, kite-carrying cats, hybrid windsurfers, match racing and all the other stuff that was supposedly going to hook viewers. If skiffs, Tornadoes with kites, match racing and shorter windsurfers didn't sell then why will foiling cats?  The top rating Olympic sports are people running, doing gymnastics and swimming in a straight line at 4 knots.

That is likely because few people can relate to a Tornado or 49er. Fewer still a foiling cat. Everyone can relate to a runner and swimmer, and many folks get some exposure to gymnastics at a younger age. Also, many of these athletics have a story; few Olympic sailors learned to run to and from home on the streets of Nairobi... 

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That is likely because few people can relate to a Tornado or 49er

I think this is irrelevant.  World Sailing understands that the Olympic TV viewer is watching for a reality show.   They want to watch individuals from their country.... (or the media images shaped by the Olympic marketing machine)   live or die on the ONE CHANCE for greatness.   Win or be eliminated adds the drama.   Sailing tries to twist the racing game into this reality show format with the fleet races leading to a cut and a high stakes medal round.  The sailing reality tv show game is better but not revolutionary. 

The fundamental issue is how to capture the decisive moments of high drama...  In sailing... you can't see the wind.... so you are forced to record the mistakes.   Second point.... for a TV reality show.... you need to constantly reset the action.   Each point in tennis is a new challenge.... each pitch in baseball is a chance for a game changing home run, each turnover in football resets the action..  The viewer knows the structure.  Sailing does not enjoy a structure that continually resets the competition in such an easy to digest manner.

As for the New N17....  World Sailing and Nacra control the rule set and the source of ALL of the gear.  Nacra wants to make money while World Sailing wants to guarantee "fairness"   They would LIKE the boat to work properly but its not the major objective of either organization.  The first try was half assed... ( Mind you.... It took 4 years for the sailors to public state... this boat sucked!) .  the second try may not prove to  be much better.

Having had a tiny tiny role in the initial US process.... the mention of Morelli and Melvin were the magic solution to all things technical and all members of the technical committee were convinced that they could partner and deliver a great sailing boat.   History shows that much more is needed.

Compare the current  NACRA/World Sailing  class structure to the last olympic cat class, the Tornado, now celebrating 50 years of competition this year.   The class rules allowed the boat to evolve within its box and optimize its performance,with multiple builders, vendors, etc etc..   Nobody argues that the Tornado was not and is not a modern and highly refined machine BECAUSE of this process.    However, from ISAF's point of view.... that space for evolution and technical improvement created an unfair playing field and so  good riddance from the Olympics.

As a sailor.... I would choose the structure that drives the evolution towards a great boat without roadblocks from World Sailing and the builder.  Its about the Process!

The sailors had so little confidence in the NACRA/World Sailing management that almost half the class would have been happy with t foil rudders.    Bottom line... we are where we are in 2017 because of the fundamental choice in what we wanted and how we implemented Olympic equipment selection.   Nothing can change until we address the underlying philosophy.

 

 

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On 8/2/2017 at 0:37 AM, Tcatman said:

Compare the current  NACRA/World Sailing  class structure to the last olympic cat class, the Tornado, now celebrating 50 years of competition this year.   The class rules allowed the boat to evolve within its box and optimize its performance,with multiple builders, vendors, etc etc..   Nobody argues that the Tornado was not and is not a modern and highly refined machine BECAUSE of this process.    However, from ISAF's point of view.... that space for evolution and technical improvement created an unfair playing field and so  good riddance from the Olympics.

As a sailor.... I would choose the structure that drives the evolution towards a great boat without roadblocks from World Sailing and the builder.  Its about the Process!

Not this old shit again! I enjoyed Tornados more than maybe any other boat, but that doesn't change certain truths. That evolution cost a fortune and made it unsustainable for the Olympics. Diehard tornado sailors keep coming up with the comment about the class being cheap because the platforms last so long. Bullshit! Before the one design masts, team spent a fortune on masts. Everybody was trying different sections, custom acid etching the tops and even getting custom dies made in order to try to find an advantage. This sort of development went on in other areas. One country spend huge on developing new foil sections, employing a top designer. As for sails, that was a non stop drive to develop something nobody else had. being the most expensive sails in the Olympics, this led to the biggest sail development budgets. Even the platforms were subjected to big spends by a few. While the Marstrom was considered the default and best, some spent big on designing and building new platforms with different hullshapes. Don't judge the success or otherwise of all this money being spent as to whether it was needed. All that matters is that the money was spent, killing the myth of the class being a cheap campaign because platforms lasted. The attempts to control things came too late. If the Tornado had been made a strict one design, it might have survived but by the time they were looking for a new Olympic cat, the Tornado looked dated even if the performance wasn't.

There are 2 completely different issues going on. One is getting the correct design. In the case of the N17, the original boat was fine as a design. Whether the new foiling boat is good I don't know, but if the foils have been rushed to meet a deadline and aren't as good as they could be, I think back to the early A Class foils which were far from good or easy to use but still gave great racing because it's the same for everybody. It's a shame they didn't have more time and maybe it is a shame that they didn't have the top foilers doing the development work, but it isn't a big issue. 

What remains more of a concern is the boat quality and that is a completely different issue. I am not sure how much you can blame World Sailing for choosing a product from a major, well established builder used to building large quantities if that manufacturer then builds a shit boat. Nacra dropped the ball on this one. Maybe the original bat was under specced or manufacturing was sloppy, but again, you cannot blame World Sailing for that because they cannot be expected to have boat building experts on their staff. It was a reasonable decision to choose the Nacra 17 and it was only after the problems arose that smart arses began saying it was predictable. Now, as a reaction to those problems, there is a suggestion that the new boats are over built and heavy. Is that surprising? There is o way anybody would risk the boats falling apart again and short of years of testing, the only way to be sure is to strengthen it right up.

I think it is tie to stop bashing WS or even Nacra and let the boats get on with this cycle. What I have seen on the coverage so far shows a lot of promise and if the boats hold up, I would say "good job".

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Lots of learning happening, at least one of the boats used their spin off the start line, upwind in light wind until they were foiling then were able to carry two on the wire, they sound like they are enjoying the boat and the learning process

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Hope you watched the Nacra 17 Europeans race on Facebook, they had cameras on Nacra 17's, on speed boats and in the sky on drones, terrific commentary and the racing looked awesome even though it was only 6 to 7 kts they twin stringed foiling downwind, then rounded the bottom mark where most of them kept the spins up for a fair while upwind. The boat I saw douse the spin at the mark lost about 4 lengths. All that in light wind, windier day forecast tomorrow so try and catch it

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On 7/30/2017 at 7:23 PM, Team_GBR said:

The new foiling Nacra 17's are at last up and racing at the Europeans. The first batch were eventually delivered, late, which was no surprise. I am hearing some pretty disturbing things. They have a non foiling, C foil at the Europeans as well, so we can see the old and new side by side and the comparison isn't exactly favourable. Looks like the old boat is faster in most conditions and that the foiler isn't as nice a boat to sail. There are a number of reasons. The new boat is now 20kgs heavier as they have tried to make the boat bomb proof after the boat issues of the first olympic cycle and the foils being made super heavy to eliminate all chance of breakage. The extra weight makes the boat feel really sluggish. The other issue is that it seems like the foil design is poor. It works OK in flat water, but even then, there is a problem with uncontrollable and unpredictable ventilation that nobody has got to the bottom of. I don't believe it is leading to capsizes, but the sudden drop from foiling to floating isn't good. The boat doesn't foil upwind in waves because the handling is too unpredictable. I don't believe that this is due to lack of experience on the boats, because some of the teams have been practising on A's and say it is a foil design issue. The foils are too big, have the wrong profile and the section isn't great. Because the foils are so big, they are very draggy which is why they are slower upwind than the old boats.

The suggestion is that (yet again) the boats have been rushed to market without enough development. It is rather disappointing because the Nacra sailors have had a bad enough time of it and deserved a properly developed boat. At least it seems that for this cycle, the boats won't fall apart and at least it is the same for everybody. They cannot change it for this cycle, but the smart money is on a new foil package after 2020. 

Great analysis Team_GBR! ......:unsure: :lol:

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New boat faster around the track than old boat by something like 3 minutes today according to RO.  Far quicker in the light with the spinnaker upwind, and 2-4 knots faster downwind in 15.  Crews dig it, mostly, and I've spoken to most of them here. Interviews up on Facebook.com/nacra17sailing to hear them.  Some bitching from two crews, the rest seem happy.

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11 hours ago, madboutcats said:

Hope you watched the Nacra 17 Europeans race on Facebook, they had cameras on Nacra 17's, on speed boats and in the sky on drones, terrific commentary and the racing looked awesome 

Thank you!

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On 7/31/2017 at 5:06 PM, SCARECROW said:

Except of course Nacra did close to nothing.  M&M did the design work and Element 6 built the boats.

Holland composites.

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Agreed, really enjoyable watching. There was a short section where I couldn't tell if the guy who wasn't Clean's mic went down, but that's not your fault. Although, it is Frascari, not Francari as your co-commentator kept saying.

That said, as enjoyable as the TP52 and 18fter coverage, if not more. On-board footage was a great addition.

Boats look like they aren't perfect, and I have seen some concern on Facebook about different board tips (squared off vs rounded off) from factory, but as long as that's sorted and it's quick, tight one-design racing, I'm all for it from a spectator who occasionally enjoys foiling cats' point of view.

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3 hours ago, MR.CLEAN said:

Some bitching from two crews, the rest seem happy.

Maybe I have been listening to the wrong people! Or maybe what people are prepared to say to the camera is different to what they are saying in private.

 

3 hours ago, MR.CLEAN said:

 Far quicker in the light with the spinnaker upwind, and 2-4 knots faster downwind in 15.  

Upwind, in winds up to about 6-7 knots, they are quicker with the kites up but as soon as they come down, they are significantly slower unless you can foil upwind because of the drag from the foils. Darren Bundock comments on this in one of the interviews. 

I have to admit that what I see on the video feed is pretty compelling and a big improvement on the C foil boats. Whether that is relevant is another question. The boats seem easy to sail but I suspect they are very hard to sail well, with the different upwind modes (kite/no kite, foiling/not foiling). It will be interesting to see if this leads to big gaps. If you get a puff and foil when others don't, you should be able to pull out significant distance upwind. Downwind, everybody will be foiling so it seems to me that upwind is where all the action will be. Time to change back to upwind finishes?

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Waterhouse and Darminian won a race yesterday foiling upwind considering Waterhouse has been out injured that's a pretty good effort, There was a direct comparison between foiling upwind and not with the boat that's coming second overall travelling 500 metres less non foiling upwind and the Aussie boat travelling 500m more for the win after trading tacks. Give it another season and everyone that deserves to be in the Olympics will be foiling and the ones that can't work it out will be complaining. Thanks for the coverage Clean that was more entertaining than the rugby that was on TV at the same time,

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1 hour ago, Team_GBR said:

The boats seem easy to sail but I suspect they are very hard to sail well

This describes just about every racing cat on the market.  The first 95% is easy.  The next 4% takes experience.  The last 1% is fracking hard to find.

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Interesting to hear Bundy's comments on the Australian team's bookface page about part of the reason the boats are slow upwind in the light is because they're not allowed to pull the windward board up.  If that is genuinely an issue it would be a very easy fix.  Of course the flipside is if it effecting everyone the same is it really an issue?

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5 hours ago, Team_GBR said:

The boats seem easy to sail but I suspect they are very hard to sail well, with the different upwind modes (kite/no kite, foiling/not foiling). 

 

4 hours ago, SCARECROW said:

This describes just about every racing cat on the market.  The first 95% is easy.  The next 4% takes experience.  The last 1% is fracking hard to find.

I will take a stab at this. Change the initial comment to "the boats seem easy to sail for a foiler". Almost anybody can get them around a course and foiling downwind. Foiling gybes are already happening. The issue is that the gap between sailing reasonably well and very well has been illustrated by Jason's win of nearly 500 metres. The others will need to get up to speed with the upwind foiling, but I would bet that it will never be a clear cut case of when to foil and when not to, which could lead to some very big margins.

3 hours ago, SCARECROW said:

Interesting to hear Bundy's comments on the Australian team's bookface page about part of the reason the boats are slow upwind in the light is because they're not allowed to pull the windward board up.  If that is genuinely an issue it would be a very easy fix.  Of course the flipside is if it effecting everyone the same is it really an issue?

The issue isn't straight forward. i believe that the boats will not foil without both boards down. Allowing lifting of the windward board might not be desirable as it increases the chances of a team making huge gains. Sure it is a skill but big separation isn't good for the game. I say leave it as is, with both boards down, as it is the same for everybody.

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13 hours ago, madboutcats said:

Waterhouse and Darminian won a race yesterday foiling upwind considering Waterhouse has been out injured that's a pretty good effort, There was a direct comparison between foiling upwind and not with the boat that's coming second overall travelling 500 metres less non foiling upwind and the Aussie boat travelling 500m more for the win after trading tacks. Give it another season and everyone that deserves to be in the Olympics will be foiling and the ones that can't work it out will be complaining. Thanks for the coverage Clean that was more entertaining than the rugby that was on TV at the same time,

I'm pretty confused, I'm about 95% Bundy was on the boat for this race. Jason may have been swapped later. I'm basing this on Cleans commentary though as the SAP leaderboard showed Waterhouse/Darminian. I'm a fair bit more comfortable thinking it was Bundy only because he is one of a few elite sailors that have proven faster foiling the A Cat upwind with a similar foil configuration. No one else could really make it pay, the Germans tried it in the second leg upwind yesterday in the second race and they lost big.

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According to the coverage the Coach substituted Waterhouse for most races (back injury). Maybe not for the last one or two races, that was not too clear in the broadcast.

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Yeah that is what I thought per the coverage. The N17 site is saying something different, and given some of the errors in Cleans reporting (not all his fault, delayed video/analytics etc.), I'm inclined to go with the official reporting.

Anyway I have to say the racing is pretty exciting, very close action even at this stage of the game. The coverage is pretty phenomenal, need to get a custom waterproof 60 kt drone out there though.

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Wow!  I have been really enjoying the racing coverage.  Great Job.  The z foils look like a great addition and it is interesting to see the strategy evolve in how to sail these boats well in these early learning races.  Actually a lot more interesting than watching this last Americas cup.  Hope to see the Nacra 17 and 15 expand to local fleets and my local sailors / youth.

 

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If my experience with the C-foil N17 is anything to go by, keeping the boards down all the time will be a great way to avoid a great many crew injuries. The C-boards load up and lock in place very easily, as you'd hope since they need to stay down when giving lift. But that means you have to be absolutely spot on with your timing pulling them up and down during maneuvers and doing that over months and years of training and racing is just a recipe for back injuries. Lubrication helps a bit but it's still a big issue, and keeping them working smoothly will add a lot of maintenance time all by itself. So I think it's just awesome that they are stuck down for the next four years.

By the way, it's cool when you do get enough lift that the hulls just come out of the water. A lot of boats hum when they go fast, this one goes quiet.

Thanks for the efforts Mr. Clean, loved watching the coverage.

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10 hours ago, samc99us said:

I'm pretty confused, I'm about 95% Bundy was on the boat for this race. Jason may have been swapped later. I'm basing this on Cleans commentary though as the SAP leaderboard showed Waterhouse/Darminian. I'm a fair bit more comfortable thinking it was Bundy only because he is one of a few elite sailors that have proven faster foiling the A Cat upwind with a similar foil configuration. No one else could really make it pay, the Germans tried it in the second leg upwind yesterday in the second race and they lost big.

It was Jason who was helming when he won by 500 metres. We know this from an interview with the crew, who commented on how when Bundy got back n the boat, the wind died. I think Jason did 3 races up until the last day.

It shouldn't come as a surprise that Jason is as good at foiling as he is. He has done well in foiling A's, hs been sailing lots f foiling boats during his time with the AC and is coached by one of the best foiling A Class sailors. One of Jason's strengths in the C foil boat was his foiling ability. Before the event they did a pretty solid training block. I think it would have been a surprise if he wasn't one of the top foilers to start with.

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16 hours ago, samc99us said:

Anyway I have to say the racing is pretty exciting, very close action even at this stage of the game. The coverage is pretty phenomenal, need to get a custom waterproof 60 kt drone out there though.

We'll see what drone they have next event. Looked like they splashed this one during the coverage.
Or perhaps skip the nice ones and just buy good enough used drones for cheap...

The coverage was good. As always every little bit of experience goes a long way. It takes time to get rid of bugs and develop coordination between commentators (& everyone else in production).
Having actual experts helped a lot. Voluntelling the class manager should be rather cheap. :lol:

I think the analytics website could have been mentioned a bit more. Playing with it alongside the live stream was cool. 

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So here we go again. The medal races at the worlds trial event have been cancelled because all new foiling Nacra 17's have been recalled to the factory and their owners have been told not to sail them. The c/b case bottom bearing needs replacing and I guess that continued sailing could screw up the bottom of the boat. Another fine mess from Nacra.

I hope for the sake of all the sailors involved that they get it sorted double quick.

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At least they seem to be acting proactively. Not an optimal situation though. Hope they get the issues figured out ASAP. Maybe they jumped on the foiling bandwagon too early, but then again with the AC already flying and VOR soon to be foil assisted, I guess there was some pressure mounting up to have at least one "modern" class. 

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The boat in the c board configuration was a pain to sail, less than robust, not extremely fast etc. This incaration is better from all reports. It's not Nacra fault their hull builder closed the doors late last year and they had to start over with a new builder basically 6 months ago. Hard to deliver boats under that situation. Marstrom had the advantage of in house production, but the days of building reasonably priced boats in Northern Europe or the U.S for that matter have long since sailed.

Bottom bearings: this is an unfortunate situation but not the first time. One prominent A cat builder has had the same problem. Hopefully it is fixed in a prompt manner.

 

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Yes, after reading the report, I'm a bit concerned about my A-cat trunk exits which are identical to the fixed bottom bearing plates Nacra used in the first N17 Mk. 2's. In my case the loads are a lot lower and the boards used are solid in that area, which I think may have contributed to Nacra's N17 issue (they used the Exploder bottom exit support design with the DNA Z-board hollow/foam based structure, I'm pretty sure Exploder are solid carbon or nearly solid through the bearing exit area). I think the pivoting bearing is a good long term solution and hopefully it can be rolled out quickly to all affected sailors.

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First time post! Seriously. I began racing Bim HT's when the first one was delivered to Smyth. We were training in the Gulf of Mexico in January, which is pretty cold for Florida but we had six boats and a 2003 Worrell to prepare for so what the hell. The Worrell was canceled and the first boats needed a small amount of beefing for that race. The weakness's were overblown but very valid considerations and 20 feet is better than 18 so though Lambert and some others went on Tybee500 with them, I prefered the 20's for the Atlantic.

So I still have us49 and my older back is not interested in being broken by heavier boats and I prefer two man racing. Mathew Smyth started sailing with me midsummer and I had a great season. I had been trying to get some assistance with converting it to a foiler for some time and Randy, Matthew were all over it. Randy has become very proficient at carbon parts and has taught Mathew a lot. Trained all fall with our rudder winglets and knocked boat down for mast fairing, spreaders, boomerang rotator, sharp bow, new well trunks, beefed rudder fittings, new slick luff tape and main recut to decksweeper.

We are proficient at foiling on our Acat Exploder Z10's now, no cavitation issues, what a rush, and our weak link is the makeshift converted bim rudders. Can anyone recommend stock rudders from an F16, the strongest Acat rudders available, N17's, or any other rudders and castings available and reasonable cost?

Close ups of our fittings available if anyones interested.

I.J. foiling 1.JPG

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There's an update to the update, and I'm sure there'll be a couple more in coming days. http://nacra17.org/update-on-nacra-recall-and-bearing-replacement-plan/ -- they'll do well to number them, or date them :-)

My read on this is -- most of these foiling systems are operating towards the limits of materials/design. So the weak points will be found, some in the lab, some in the field. Given the time and competitive pressures, they are damned if they do, damned if they don't.

The obvious, time-proven method to shake these bugs off -- give early access to the hardest-hitting teams -- would have put some teams in advantage.

I hope that these new cassettes, and the overall rig, are without major issues.

WRT similar trunk exits, I'd say that they share the same weakness, but perhaps get a little bit less stress, or in a slightly different angle/format. Long term, it seems to me that the pivoting cassette is the stronger solution, and should be the way to go on any boards that are not straight.

(My notes and opinions are based on hard-earned Industrial Design / Mechanical Eng / Plastics and Electronics Manufacture lessons from a different field. My foils are straight so this particular issue doesn't affect me :-) )

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The A's are subjected to far lower loads, so maybe it isn't surprising that a system that works on them doesn't work on a boat that has a so much heavier all up weight. I would be interested to know what bearing the detuned Flying Phantom uses, as that will be taking even more load. The other concern has to be the boards themselves. They already admit to a manufacturing quality issue, but imply the boards are strong enough. While DNA have always sorted the problems, they have struggled to make boards strong enough, particularly in the C board era, and I wonder if there isn't some fundamental problem in their board laminates.  As Sam suggests, the Exploder boards are pretty solid where they come out of the case and maybe that is needed on the N17 because even with the new bearing, the exit is still a high load area and will find out any weakness over time.

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The Z10 is flying an 18HT?  How cool!  I guess there is no issue then with that board for the A.  I have never seen one fail anyway, but, Sam, that should make you relax.

I have thought the eXploder Z10 type of design with an oversize board and bearing at the exit and then an optimized foil section under the water that is smaller is a clever way to build.  I wish they had done that from the beginning.  I think it would be great a solution for the N17 as well.

The rotating bearing is a very nice design too, though I have seen some people struggle with reliability of the rotating bearing.  For example, it is possible to put the board through such a bearing without being in the slot and damage the bearing.  I am sure the N17 sailors will adapt and take the proper care and clearly Nacra is motivated to give them good gear. 

MGMurray, the rudders are the most important part for quality foiling.  I'm not sure any are built to take the 18HT loads though maybe it doesn't matter so much once you are flying.  I would consider either the eXploder rudders that work with your Z10s or the N17 new cassette rudders.  The eXploder ones are likely cheaper and there are probably some in stock in St Pete, FL at Emmanuel's.  If you go that route, you will want whichever rudders he has with the largest winglets as you have a heavier boat than the A. 

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First time post! Seriously. I began racing Bim HT's when the first one was delivered to Smyth. We were training in the Gulf of Mexico in January, which is pretty cold for Florida but we had six boats and a 2003 Worrell to prepare for so what the hell. The Worrell was canceled and the first boats needed a small amount of beefing for that race. The weakness's were overblown but very valid considerations and 20 feet is better than 18 so though Lambert and some others went on Tybee500 with them, I prefered the 20's for the Atlantic.

So I still have us49 and my older back is not interested in being broken by heavier boats and I prefer two man racing. Mathew Smyth started sailing with me midsummer and I had a great season. I had been trying to get some assistance with converting it to a foiler for some time and Randy, Matthew were all over it. Randy has become very proficient at carbon parts and has taught Mathew a lot. Trained all fall with our rudder winglets and knocked boat down for mast fairing, spreaders, boomerang rotator, sharp bow, new well trunks, beefed rudder fittings, new slick luff tape and main recut to decksweeper.

We are proficient at foiling on our Acat Exploder Z10's now, no cavitation issues, what a rush, and our weak link is the makeshift converted bim rudders. Can anyone recommend stock rudders from an F16, the strongest Acat rudders available, N17's, or any other rudders and castings available and reasonable cost?

Close ups of our fittings available if anyones interested.

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Emmanuel has a rudder set that evolved with the z10's to get us going. The reservations that I had about z10 size mostly were unfounded. As we evolved, it was essential to get modern rudders and ones that matched our boards is a bonus. The upwind speed is close to a well sailed acat and we have not foiled a lot upwind but reaching and running speeds are greater than any acat, so extra speed allows us to fly easily. Add light boat and featherweight crew and foiling is becoming very natural, no more coaxing, just flight!

Upwind foiling will still be very possible with more practice. Sailing fast and sailing flat are essential to fly. 

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From foiling week fb

accident for Bora Gulari on Nacra. in a capsize he did hit the foil edge and cut off fingers. very concerned. we hope for a quick recovery for our friend.

 

Article in  italian. The say he lost 4 fingers :(

http://www.saily.it/news/bora-gulari-scuffia-e-perde-quattro-dita

 

Hope the best :(

Edit. I start another topic, cause it's another (very sad topic)

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Update - Gennaker Upwind at Worlds – Proposed Vote by Entrants at the Open Forum

Overnight one of the Class Executives, after training, changed their view on the issue of using the gennaker upwind at the World Championship next week. They now believe that we should NOT allow the use of the gennaker upwind even this close to the start of the Championship.

As a result there is now a split among the Executive. While ordinarily I can cast a deciding vote I believe the best course of action is to have a discussion at the Open Forum on Sunday night with a vote to be taken by those entered in the Championship.

That being said my PERSONAL view is that we should not allow the use of the gennaker upwind next week. The mast, boat, gennaker etc. were not designed for the loads of upwind gennaker sailing. We also had some injuries to crew at the Europeans as a result of the strain.

Nacra Sailing has already offered resources and assistance to the Nacra 17 Class to investigate a set of specification

 It goes without saying that the Class can absolutely ask Nacra Sailing to investigate a change in specification to allow for these extra loads in the future. 

 It would be helpful ahead of the vote to commence a discussion on the Class Facebook forum with the varying views by entrants.

 I am working on wording with the PRO and Chair of the Jury that would amend next week’s Sailing Instructions to rule out using the gennaker upwind. I will post that proposed wording in due course.

To be clear – we are only talking about the use of gennakers upwind at the World Championships next week.

regards,

Marcus Spillane

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Seriously? This is pure crap. So what happens if there is a wind shift on a leg? When is upwind no longer upwind? Imagine the protests. the wind shifted 91 degrees so I put up the kite. No it didn't, it was only 89......... As or the injuries, somebody hurt a muscle. Wow. Stop the racing. It's too dangerous!

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http://www.santacruzsentinel.com/general-news/20170901/us-sailing-seeks-inquiry-into-capsize-that-injured-olympian

 

4 hours ago, A Class Sailor said:

Seriously? This is pure crap. So what happens if there is a wind shift on a leg? When is upwind no longer upwind? Imagine the protests. the wind shifted 91 degrees so I put up the kite. No it didn't, it was only 89......... As or the injuries, somebody hurt a muscle. Wow. Stop the racing. It's too dangerous!

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4 hours ago, A Class Sailor said:

Seriously? This is pure crap. So what happens if there is a wind shift on a leg? When is upwind no longer upwind? Imagine the protests. the wind shifted 91 degrees so I put up the kite. No it didn't, it was only 89......... As or the injuries, somebody hurt a muscle. Wow. Stop the racing. It's too dangerous!

I suggested like the M32s do it.  If they fly a kite on the upwind leg, they can't use the racks.  Just ban trapezing when using the kite on the beat and you're good.

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8 hours ago, A Class Sailor said:

Seriously? This is pure crap. So what happens if there is a wind shift on a leg? When is upwind no longer upwind? Imagine the protests. the wind shifted 91 degrees so I put up the kite. No it didn't, it was only 89......... As or the injuries, somebody hurt a muscle. Wow. Stop the racing. It's too dangerous!

 

5 hours ago, MR.CLEAN said:

Clean

Try keeping up! I was not referring to Bora's injuries. I was referring to the comment made by Spillane about use of the kite upwind that said "We also had some injuries to crew at the Europeans as a result of the strain."

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5 hours ago, MR.CLEAN said:

I suggested like the M32s do it.  If they fly a kite on the upwind leg, they can't use the racks.  Just ban trapezing when using the kite on the beat and you're good.

Either i made the point badly or you missed it. What happens if there is a wind shift? If the upwind leg ceases to be upwind, what happens.

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A change in the sailing instructions posted last night states 

Quote

A boat shall not set the gennaker when sailing on a leg to mark 1.

I would love to hear the reasoning behind the competitors voting that way and how close a vote it was.

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21 hours ago, A Class Sailor said:

A change in the sailing instructions posted last night states 

I would love to hear the reasoning behind the competitors voting that way and how close a vote it was.

Of the people who voted for the change you probably have an equal split between people who:

1. Believe the shit about breaking the boat and don't feel they have the budget to risk it.

2. Aren't confident they know the cross overs on when it pays off so want the option eliminated.

3. Don't think their crew has the strength to make it work.

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So what are they going to do after worlds, ask NACRA to re-engineer the mast and kite to handle the loads? That seems unlikely.... 

On 9/2/2017 at 1:45 AM, MR.CLEAN said:

I suggested like the M32s do it.  If they fly a kite on the upwind leg, they can't use the racks.  Just ban trapezing when using the kite on the beat and you're good.

Banning trapeze while using the kite upwind is probably the easiest way to enforce this rule, but I still don't understand why it matters. If everyone's doing it doesn't it just become part of the game?

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There is more compression on a mast with people sitting hiking on the hull than trapezing.  I actually find it hard to believe there is a major difference in compression on the mast going upwind with the kite in 5 knots and upwind without it in 25 knots.  The only added load in the lightwind case is the Kite halyard tension and added tension here will mean a reduction in jib halyard.

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http://www.sailingscuttlebutt.com/2017/09/05/making-headlines-for-the-wrong-reasons/

Making Headlines for the Wrong Reasons

As if the planet didn’t need more proof that quality and competence are components that can’t be rushed, the Olympic multihull event continues to prove how necessary the maturation process is for equipment used at this level of competition.

Designed specifically for the 2016 Games, the Nacra 17 has been plagued by problems since its launch after the 2012 Games. If the boat wasn’t breaking, the inconsistent measurement assured an uneven playing field. The fact how the boat handled like roller-skates on an ice rink was an additional “thrill.”

Eager to be ‘new and improved’ for this next quad leading up to the Tokyo 2020 Olympics, the class continues to trip over its bows. The transition to new fully-foiling blades has been a nightmare, with gear failures and replacements continuing to be the norm.

And as if the boats weren’t dangerous before, now as a fully-foiling machine, American Bora Gulari saw how an explosive capsize can remove bits of his fingers. As they say, if it was easy anybody could do it, right?

After the boats were deemed too dangerous to sail at the European Championships in August, more new replacement parts have theoretically made them safe for the World Championships now being held in La Grande Motte, France.

But still there remains a question of measurement…

After the American duo Riley Gibbs and Louisa Chafee led the championship after the first three qualifying races in light winds on day one, they were protested after racing for a measurement infringement and their penalty dropped them to 27th place.

Foiling kiteboarder and 49er racer Gibbs, 21, paired with Rio Olympian Chafee, 25, opened with a second and two first places but were subsequently protested and penalised for sailing with the rubber bushes at the top of the foils removed, contrary to the International Jury’s interpretation of the measurement rules.

The young Americans, training partners of injured Gulari and Helena Scutt, had been training with the bushes removed in order to preserve maximum strength in the head area rather than seek a performance gain were it to allow the foil to drop lower. A good move, one would think, since the boards had been breaking.

“This is not about any performance gain; this is about the strength in that part of the board,” Scutt emphasized after the hearing. Added USA coach David Howlett, “We had the boards not once, but twice, to measurement like that and so we considered it was fine.”

With the young American pair receiving a 50 per cent place penalty for each of their races, John Gimson/ Anna Burnett and Ben Saxton/ Katie Dabson now lead a British Sailing Team 1-2 at the top of the World Championship standings with New Zealand’s Rio Olympians Gemma Jones and Jason Saunders in third.

Racing is scheduled for September 5 to 10.

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I read that article and a comment by a one time  SA poster, which I have to agree with. It is sensationalism with little grounding in fact. The boats were not deemed too dangerous to sail. The problem was that boards were breaking and with limited supplies, they didn't want any more to be broken. I am not sure how a broken centreboard suddenly makes the boats dangerous. I have seen boards break on A's and they didn't become dangerous. I also doubt that Bora's injury was anything to do with the N17 as such. It happened while sailing a foiling boat but that is all we know at the moment. There were some pretty big wipe outs on the old N17's as well.

I also see that somebody called bullshit on the claim that the rubber stops were removed to stop the board breaking and that it was not about performance. I am not sure how being able to push the board down more helps stop it breaking, but I do know from the A's that pushing the board down a little more sure helps foiling. It would be interesting to know if they have had more board breakages since they fitted the new bearings because if that has happened, then there is a problem with all the boards and they will need to be replaced. 

To date, i think Nacra and the class association have been far more open and taken quick action to address issues, which is an improvement on the previous Olympic cycle. I therefore think the above article is unfair.

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7 hours ago, SCARECROW said:

There is more compression on a mast with people sitting hiking on the hull than trapezing

Would disagree with that

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Do the maths.

with crew hiking off the hull, boat weight and crew weight is transferred to the mast by the side stay.  At say 20 degrees.  Put the crew on trap and their weight is now transferred to mast via trap wires at 25 degrees.  

Its like the maxi CQS increasing their  spreader base to reduce loads on the mast after fitting DSS

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However the boat loads up a lot more adding further compression and you can carry the kite upwind in more pressure.

Another issue would likely be where the mast rotation is set going upwind.  No doubt they are adding downhaul at the top end of this mode and one of the pics showed a main that was eased slightly...... everything you could possibly do to put the rig under a lot of pressure.

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26 minutes ago, SCARECROW said:

Do the maths.

with crew hiking off the hull, boat weight and crew weight is transferred to the mast by the side stay.  At say 20 degrees.  Put the crew on trap and their weight is now transferred to mast via trap wires at 25 degrees.  

Its like the maxi CQS increasing their  spreader base to reduce loads on the mast after fitting DSS

Your maths needs to account for the increase in RM due to the crew weight being further outboard. 

 

As as a guide the compression increases by about 50% of the RM increase. 

 

So for sure the compression is higher with crew on trapeze. 

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It's going to be a couple of days before I can sit and my computer to draw a sketch and prove my point and I don't think any of us care that much... I know I don't.

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On 9/2/2017 at 9:54 AM, A Class Sailor said:

Either i made the point badly or you missed it. What happens if there is a wind shift? If the upwind leg ceases to be upwind, what happens.

if it's 5 knots, use the kite and don't trap.  If it's heavier than that, take the kite down and trap.  Or make sure you have good enough PROs that they blow it off when the first boat tacks on a run

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17 hours ago, A Class Sailor said:

I read that article and a comment by a one time  SA poster, which I have to agree with. It is sensationalism with little grounding in fact. The boats were not deemed too dangerous to sail. The problem was that boards were breaking and with limited supplies, they didn't want any more to be broken. I am not sure how a broken centreboard suddenly makes the boats dangerous. I have seen boards break on A's and they didn't become dangerous. I also doubt that Bora's injury was anything to do with the N17 as such. It happened while sailing a foiling boat but that is all we know at the moment. There were some pretty big wipe outs on the old N17's as well.

I also see that somebody called bullshit on the claim that the rubber stops were removed to stop the board breaking and that it was not about performance. I am not sure how being able to push the board down more helps stop it breaking, but I do know from the A's that pushing the board down a little more sure helps foiling. It would be interesting to know if they have had more board breakages since they fitted the new bearings because if that has happened, then there is a problem with all the boards and they will need to be replaced. 

To date, i think Nacra and the class association have been far more open and taken quick action to address issues, which is an improvement on the previous Olympic cycle. I therefore think the above article is unfair.

Does anyone have photos of said bushings? I'm also curious on the specifics of this. Basically the followup protest against the technical committee, who twice inspected the boards, found the technical committee had done no wrong: http://manage2sail.com/en-US/Home/DownloadReport/event/bd39e39f-b84f-4603-a438-52d55d110e59/report/c7248af8-74e8-48ba-bed5-1f68ff82da6b?isOnbReport=true

I suspect the TC may also be part of the protest committee or certainly granted some favoritism. If the pre-event inspection is not a guarantee of class conformity what is? Certainly if you made a change post inspection but pre-racing and were subsequently found in violation I understand the protest. Otherwise? Sorry, the TC/Measurement committee made a mistake from my view. Keep in mind the same Australian boat that protested the Americans subsequently filed protest against the TC. That to me shows some class and admittance that it wasn't just an American boat trying to gain an edge (though that is probably the case, the TC should be finding these sort of things before the boats are authorized to sail, especially at the World Championship of an Olympic class).

Update on kite, sort of: http://nacra17.org/series-of-votes-stabilizes-nacra-17/

This raises more questions than answers IMO. Now they want to pull boards in conditions deemed light enough by race committee after deciding the 4 point foiling solution, all boards down all the time is right for the class? Frankly I think it is less work to trim the kite upwind in light air, no masts have broken and some kites have been damaged. Far easier to change the kite laminate to one spec higher than it is to announce to the whole fleet in between races that you can or cannot pull a daggerboard each and every tack.

I'll further add some personal experience and data: I race and own a Nacra Infusion Mk. 2. This is my second Infusion. Yes, they have aluminum masts, the same alloy masts supplied at one time to the N17 fleet. I have run with the kite up upwind. I have run with the kite up double trapped reaching on a close reach with the halyard cracked 18" off and the traveler dropped. The boat has not failed me in these conditions as long as the mainsheet is kept tight. My hull laminate is probably a bit thicker but certainly not as good as carbon. My beams are weaker than those in the N17 Mk. 2. My kite blocks are identical. My kite laminate is a bit thinner (SK75) than the polyester kites supplied with the N17 Mk. 2. My crew and I generally weigh more. We push the boat just as hard as any Olympic sailor does, and for extended periods of time. I have not ripped a kite. I have not failed a Harken 55 carbo ratchomatic kite block. I have not had a front beam collapse in half. I'm not saying these aren't possible, but I am saying they are unlikely. Flying the kite upwind is self limiting because above a certain wind speed it doesn't pay. Where that lies I am not sure, but likely below 12 kts on the 17 Mk. 2 (its really very limiting on the F18 because the angle almost never makes it work upwind, but our kites are not as flat, well most are, I have sailed with very flat test kites that do pay below 6 kts upwind and place both crew on the wire). I think the biggest risk is the mast, a real risk of course, and the increased cost for the gennakers. The last is a potential decrease in long term platform stiffness and therefore competitive hull life. That is a separate debate of course.

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As per the current measures course I completed, If the rules say you have to have the bits on the boat and you take them off to lighten the boat and the measures misses it, the competitors have the right to protest, the cheats were scrubbed end of story

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Would love to see the powerpoint from that course, just for my own edification. I realize it is everyone's responsibility to keep their boat in compliance with the class rules.

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On 06/09/2017 at 8:20 PM, SCARECROW said:

It's going to be a couple of days before I can sit and my computer to draw a sketch and prove my point and I don't think any of us care that much... I know I don't.

Turns out I'm pettier than I thought.  Do any of the experts out there want to tell me where my mistake is.

 

trapeze-Model.jpg

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I don't know, but  aren't you just looking at static loads. If you are looking at compression on the mast don't we also need to look at matters such as increased mainsheet tension, downhaul loads etc.which add more compression to the mast. I am assuming that as the sail area stays the same and RM has gone up yet it is still heeled the same amount, there has been an increase in wind strength and therefore all dynamic loads have increased,

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That's a totally different argument.  my statement was that people getting on trap doesn't automatically cause in increase in compression.  If the argument is "now I have more righting moment so I can sheet harder etc.," then that is a different thing.

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shroud preload is consistant across the too cases so i didn't include it.

Reaction R1 at the chain plate is (100kg X 900mm + 80kg x 2500mm) / 2175mm

added tension in wire is then R1/cos19 degrees.  I left it all in kg as I figured converting to newtons would just confuse the metrically challenged.

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13 hours ago, SCARECROW said:

That's a totally different argument.  my statement was that people getting on trap doesn't automatically cause in increase in compression.  If the argument is "now I have more righting moment so I can sheet harder etc.," then that is a different thing.

I think I see the problem here. If the 2 boats are identical, except one has the crew on the wire and one doesn't, the only way that can happen is if there is more heeling moment from the rig because something has to counter the extra RM. Therefore, while the act if getting out on the trapeze itself might not increase compression, the dynamic loads because of getting out on the trapeze do increase.

 

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22 hours ago, SCARECROW said:

Turns out I'm pettier than I thought.  Do any of the experts out there want to tell me where my mistake is.

 

trapeze-Model.jpg

You need to make the distance of the crew from leeward hull the same as the windward hull. By that I mean you should change the 2500 to 2175 bec