UK-Cherub Forum
Off Topic => Banter => Topic started by: daryl_wilkinson on January 31, 2010, 03:47:27 PM
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This from 'Sailing Anarchy' item....
' The 29erXX was nearly selected for the upcoming Olympics despite the fact that, at present, it is not widely sailed nor widely available. Both advisory committees that are meant to choose the Olympic boats chose the 29erXX, and it was only the executive committee that overruled them by merely one vote. '
Was that really the way it played out? Be interesting to hear from them that was at the trials.
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Yes I saw this too.
That's not what I remember, nor what is found in the various minutes of the various committees which met to discuss the topic.
The trials were not held to choose a womens olympic high performance doublehander class. They were held to assess whether the equipment existed for there to be a high performance womens event at the 2012 games. The answer from the organising committee was 'yes'. The ISAF technical committee passed this on to ISAF, but the womens high performance event was never adopted for the 2012. There was quite an outcry at the time.
No event, and therefore no vote on which class to choose.
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So this is spin?
Nice touch with the pinks sails though, they sure are making a concerted effort to bag that place at 2016.
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Could be spin. It has the air of advertorial, which is exactly the kind of thing that SA was set up to get away from.
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Both committees selected the 29erXX! That stinks of spin that would even make Alistair Campbell blush. Perhaps they'd like to publish any such document to back it up? As I recall the only thing the 29er did consistently was break and get towed in.
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It was the 29erXX which broke on two days. One was a gnav problem. Don't remember the other problem.
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Well those 9er boys and girls don't seem to have the same memory of the events that you guys have....
http://www.yachtsandyachting.com/news/?article=150290 (http://www.yachtsandyachting.com/news/?article=150290)
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Probably because I don't think that anyone writing that report or sailing that regatta was at the trials. A case of SMOD Chinese whispers, if porkies are told on a global scale there is always someone who will believe it or pass it on with embelishment. The marine folk mythological equiv of the dog that choked on the burglars fingers.
If the class is soooo successful what do the new boat sales and national numbers look like or how many bring their own boats to the nationals? It doesn't take much to scratch below that micro vaneer of marketing.
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Ahh, now I get it. Would this have anything to do with marketing departments blagging event sponsors?
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Is this driven by a pocket of the class! in the states or the builders?
Thinking back to the original concept of having a womens 2 person skiff in the olympics if the cherub was sellected the sailors could be required to build at least 60% of their boat. That would create a good ballance between construction time, sailing time and reliability and bring the dinghy park to life with the sound of drills and the smell of resin after racing.
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Is this driven by a pocket of the class! in the states or the builders?
As far as I can see there are no significant pockets of the class anywhere... About all they've managed to do so far is flog off second hand rigs cheap after publicity events. So presumably it must be the builders and their mates.
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Also seen on Y&Y:
http://yachtsandyachting.com/news/?article=150290
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This what Julian B said on Sailing Anarchy...
"Hi Guys, the facts, (don't let them get in the way of a good story)
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If you go to ISAF (www.sailing.org) and pull down the minutes of the Madrid 2009 conference you will find that:-
Women's Committee, 4. (a), (ii) you will see it's recommendation for a number of "disciplines" one being double handed women and its recommendation is the 29erXX over the 470 (interestingly the chairwoman (Adrian Greenwood NZL) asked one delegated not to vote due to conflict of interest)
Events Committee, agenda item 3. (a) is the report from the various committees, inc the Events and Equipment working parties and the recommendation is the 29erXX over the 470W, The Events committee's vote/decision 3. (cool.gif recommends to council a number of classes, the class it recommends for the double handed women's slot is the 29erXX.
Then at Council, 15. (e) (ii) Vote #2 they voted for the 470 over the 29erXX 19-16 thereby staying with the status quo and over turning the decision of all their previous committees.
This is not new, and they have every right to do so, it's happened before and it will happen again.
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Re the 29erXX outside ISAF, last year every rig from the Garda Worlds event was pre-sold that was 15+ rigs
The subsequent Garda event in Sept (?) due to the success of the Worlds again all the rigs where pre-sold, think that was 10+.
Most of these rigs have gone to Germany, the rest are scattered across Europe, Italy, Spain, France and Scandinavia, 2 went to USA
There is an event on now in Miami, my understanding is most of those rigs are also spoken for (another 10)
There have been around 80 rigs sold, (1/2, as above, last year) all but 2-3 of those have been people upgrading std 29ers. Interestingly the 29erXXs sold as 29erXXs (not upgrades) sold into interesting places like Turkey, Singapore and China.
Why the slow start! Now some of you are really going to dis-agree with me here, but I happen to be male! After Hyeres we had a lot of interest, (those rigs all went also) but a group of those girls got together and asked us if we could do a number of things to the boat to make it better, to make it more user friendly to women, and made the point that "I was good, but I was not female". It was a very interesting form of "pull marketing". One of the biggest proponents of this was Jen Morgan-Glass from Seattle who is now the president of the 29er World Class Association! She sailed both 470s and 29erXX in Miami (along with 5o5s in SFO a few months back). And there are now a raft of Olympic women literally defying their coaches and in some cases sneaking out to sail a 29erXX.
I could list all of those requests those girls made, but if I had to pick one, probably the most interesting is that 29er is in fact a tad bigger than an I14 but it's perceived as being tiny. When we looked at this very carefully to find out why, the tube gunwale extension did not have enough mass and the tiller projecting into the cockpit were deemed big issues, so we changed the tubes to FRP laminates and had a couple of goes at rudder frames till we got it right. Some like it, some do not, but the perception that it is too small has gone away!
An interesting aside to that is people are asking if they can modify their 29er so they can switch between the 2 modes fast, making the rudder frame more pin on, pin off, faster. Had a long conversation with a man in Spain this morning, about just that, boat is getting used 6-8 hours a day, he is switching between the 2 so his older daughter can sail XX while his younger boy is still doing 29ers. Love it!
But what we all need to remember is boat size/length is very dependant on crew weight, if you have a big boat, you need a big crew, little boat you need a little crew or dare I say little all up weight. 49er floats 290kgs, 29er floats 224kgs and a moth floats 110kgs. And yes a Laser floats 160kgs, but a Laser cant handle the power or the rigging loads that a 29er (or a moth) can, regardless of whether it is rigged with a 29er Std rig or a 29erXX rig.
So the 29erXX is for people of a given stature, not of a given sex. All up combined weight I'm guessing of 120-135kgs (265-300lbs). In short, the 29erXX is for lighter crews that want to play in skiffs. Male or female!
The boys in the 49er class are hoping for a lot of females, but they are boys and I'm married so I'm not allowed an opinion! In Miami its very mixed, FF, FM and MM. (go and see http://www.sailgroove.org/) 49er class wants to adopt the 29erXX class, so has Seiko, the 49ers sponsor! They are actively scheduling XX events with every 49er event. Most of the 49er boys carry the girls' 29erXXs to regattas, its great.
So where we are today is that we are making 1 final change that will hold the price down, we have substituted an expensive component for one that we already use on the 49er/29er which has proven itself (you sometimes wonder why you do these stupid things)! I expect a report some time today on that and am poised to push the button. 99% of you wont even pick it other than the boat will remain very cost effective.
We have quite a few 29erXX rigs presently on order, some of the rigs from Miami may fill those slots, some will be new rigs going to new regions like South America. I am aware that some clubs in the US want to buy a couple, again, I'm expecting Miami to fill some of those, but like the Garda situation, we will run out of charter rigs pretty damn fast.
Someone before alluded to the fact that 29er's last! This is intentional, it's our design philosophy, and now some of the big European MNA's have picked up on this and asked quite specific requests of us WRT the 29er and the 29erXX as part of their plans.
2010 or dare I say - 20X - I expect to be a big year for the XX, lots of events are happening, and I expect a lot of conversions."
Julian Bethwaite
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So they decided they needed a pinned gantry. humm! where have we seen those before?
The marketing benifit is obviously a common hull as is most of the kit.
With support of the 49ers who appear to have realised that this is the only way to get a mixed class, they should do ok.
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We should keep an eye on 29er XX developments though.
The 'halo' effect could be good for us? Exposing more lightweight sailors to 2 strings with the opportunity of migration to a similar class for those into 'development'. I would countenance that with caution though. It could drag 'wavering' class membership in there direction. To a more sail-able class. So I think we should be keeping an eye on our on development to make sure we don't push new ideas to extreme's, making the boats even harder to sail. With the resultant bad rep. Consolidation is the name of the game.
And yes I have said that we shouldn't be banning 'Fully foiling' and this could be classed as extreme development. But the lessons learned from the 'R's would suggest that it makes the boats easier to sail. Given that the launch and recovery hurdle can be dealt with it.
Which leads me to the E6. The extreme fine bows suggest to me a very difficult boat to sail in any breeze, in a conventional sailing form. Which would in my view start to take us toward the wrong end of difficulty spectrum, if class growth is an ultimate goal. Given the specter of the 29erXX. On the other hand if the intention with the E6 is to 'fully foil' ( and given the boats lines and Kevin and Mikes involvement in that area it's a reasonable assumption to make ) this could be a perfect solution to the looming class competition posed by the 29erXX....
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Which leads me to the E6. The extreme fine bows suggest to me a very difficult boat to sail in any breeze
The broad bow idea is that the pitch-up static force from immersing the bow sections is more if the bow is fat. This is true if the boat is stationary. However this neglects the dynamic pitch-down caused by deceleration, which is greater than the static effect if the boat is moving at any speed. This means that there is no obstacle to finer boats being as easy or easier than broad boats in breeze, and since the Hardon, designs have been getting thinner.
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Which leads me to the E6. The extreme fine bows suggest to me a very difficult boat to sail in any breeze, in a conventional sailing form. Which would in my view start to take us toward the wrong end of difficulty spectrum, if class growth is an ultimate goal. Given the specter of the 29erXX. On the other hand if the intention with the E6 is to 'fully foil' ( and given the boats lines and Kevin and Mikes involvement in that area it's a reasonable assumption to make ) this could be a perfect solution to the looming class competition posed by the 29erXX....
1) I can state categorically that the E6 has not been designed as a foiler. It would look very different if it was.
2) Fine bows generally aid handling in a breeze for the reason Will has stated.
3) I have previously expressed my views that I believe a foiling Cherub would be a bad idea.
- It would would probably fragment the class .
Cost will increase.
It would also turn the boat into a one trick pony which only works above 10-12kts - All the Cherub development to date has made the boats perform well over the typical conditions we get in the UK. The new boats all look impressive both on and off the water.
4) Don't believe that foiler Rs are easy to sail. You only have to look at the photos of the foiler Rs offwind to notice the tentative stances of both helm and crew. Yes, Cherubs are on the more demanding side of sailing because they are quite highly canvassed, short aand have a high power to weight ratio. They fulfill a niche role as a really exciting high performance boat that can be handled by lightweights and women. If you want to make the boat easier to sail, add about 2ft 6in to the length and increase the weight by around 40kg - then you've got a 29XX.
5) I'm all for foiling - I sail a foiler. It is a really interesting development and has created a new type of sailing. The Cherub, in my view however, is not really the right platform foiling and I am sure the class will benefit from consolidation in its current format.
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Yes I agree with that view in general, and obviously it is hard to tell from the screen grabs and pics of the frames, so this is very much conjecture on my part. But the as the boat decelerates and those pitching forces come into play the buoyancy has to come in progressively. Looking at the images it looks to me as if the forces involved in pitching may overwhelm the influx of buoyancy as the bows go in and allow the weight of the rig to dictate the outcome.
But anyway this wasn't really designed to be some sort of critique of the E6. I was using my 'off the cuff ' thoughts about the new design in a more general way. To sort of kick start discussion about design conservatism and it's potential beneficial role of increasing fleet membership by creating attainable boats. As in a class as small as ours it is very easy to get into a mono-culture driven purely by competition or reputation which could lead the class into future difficulties.
Edit: this overlapped with Kevins post.
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The XX is going to be sailed by squaddies. I don't think it's going to cause any issues for class membership. If people want to sail a cherub, they will and I don't think a 90kg+ 14ft+ boat is going to stand in their way.
Surely the 49er is a direct class competitor (for want of a better phrase). It's ideal combined crew weight is around 140Kg isn't it? Which is the top end of Cherub 'competitive' weight spectrum.
Holding back class development because it's 'too extreme' or makes the boat harder to sail is a daft idea. Would we all be sailing cherubs if they were as easy to sail as Wayfarers!? Dingy sailing isn't an extreme sport. Difficult but it's pretty tame.
As for this pitching thing. A boat with a T-foil has it’s centre of pitching moment (or whatever you want to call it) is at the back of the boat. So you have 12 feet (and a cheeky bit of snout?) of progressive increase in buoyancy and given that you stand further back anyway it's more that enough. Kevin, skinnier boats please!
Off topic, but has anyone sailed the new really skinny designs without a T-foil?
Kevin, what makes a cherub the wrong platform for foiling? It's got to be the most ideal class in the UK. I guess it's just not as good as having a 2 man foiler designed from scratch. Chine width and things like that. Maybe I should move this question into a differnt topic...
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Having owned and sailed an XX for a year before getting a Cherub, I think that this is all about nothing. There are many potential classes for us to attract new sailors from 800's (Pete) 200's ( Andy and Jill ) 29ers (us) The current crop of boats look and sail very well, If we wish to attract people to the class and not lose them to others we have to offer them something they can only find with us. As a group of sailors we are very freindly not something often said about the 29ers. Pete is doing very well in showing the light to the uninitiated , Perhaps we should all try to show the way to other classes a bit more. Some people will always feel more comfortable with a smod , big turnouts at open meetings, if something breaks you just get a new bit, more sailing less bimbleing. But when all is said and done the XX was far from perfect just look at how many are out there compared to the standard rig or the 800. we should worry about our class not anyone else
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Having owned and sailed an XX for a year before getting a Cherub, I think that this is all about nothing. There are many potential classes for us to attract new sailors from 800's (Pete) 200's ( Andy and Jill ) 29ers (us) The current crop of boats look and sail very well, If we wish to attract people to the class and not lose them to others we have to offer them something they can only find with us. As a group of sailors we are very freindly not something often said about the 29ers. Pete is doing very well in showing the light to the uninitiated , Perhaps we should all try to show the way to other classes a bit more. Some people will always feel more comfortable with a smod , big turnouts at open meetings, if something breaks you just get a new bit, more sailing less bimbleing. But when all is said and done the XX was far from perfect just look at how many are out there compared to the standard rig or the 800. we should worry about our class not anyone else
I totally agree, it is pretty much about nothing. Noting JB's post listed by DW, the statements are based on the 470 replacement not the Skiff trial and as I remember the 29xx was the only applicant against the 470. The fact the result was turned over was no surprise (the writing was on the wall) and neither is it a surprise the event and subsequent meeting minutes where heavily used as marketing leverage (that what marketing departments exist for).
By their own admission they are selling rigs not hulls consequently it can only be a compromise. Form a commercial point of view, and in the SMOD ideal, it is a sensible solution and I dare say they learned a lot form the other classes at the trials, nothing you can or should do about it. As for 9er's co-operating together to promote the XX in joint events and sponsors was always going to happen (could you ever see the 49er's co-operating with a competitive design to the 29er or 29erXX?) it is a natural process in developing and maintaining a sales and parts monopoly. There is a place for this, someone people will want to buy off the shelf, no question. Should the Olymics be a platform for supporting a commercial monopoly and is that good for development in the sport? I don't think so. Are there other ways to have consistant design, measurement and performance in an olympic class without a commercial monopoly behind it, absolutely.
One interesting thing will be how the 29er layups last with bigger loads & a bigger pounding.
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To reply to the off topic question posed we sailed the E5 about 10 times with no t-foil. It became apparent simply due to the reduction in capsizes that adding a t-foil makes a significant difference, in our case to sideways stability rather than stopping the boat tripping up. The t-foil seems to give that vital fraction of a second longer to move your weight inboard or outboard and does seem to make more of a difference at greater speed. I'm sure the fluid dynamic experts amoungst us could theorise why? In short adding the t-foil made the E5 a much more pleasurable experience to sail. As I'm sure Kevin would point out that should be no surprise- it was designed to be sailed with one.
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To reply to the off topic question posed we sailed the E5 about 10 times with no t-foil. It became apparent simply due to the reduction in capsizes that adding a t-foil makes a significant difference, in our case to sideways stability rather than stopping the boat tripping up. The t-foil seems to give that vital fraction of a second longer to move your weight inboard or outboard and does seem to make more of a difference at greater speed. I'm sure the fluid dynamic experts amoungst us could theorise why? In short adding the t-foil made the E5 a much more pleasurable experience to sail. As I'm sure Kevin would point out that should be no surprise- it was designed to be sailed with one.
The T foil adds roll stability exactly as you've noticed. As you roll, the tips are being asked to move faster upward/downwards through the water than the centre of the span. This means a torque is generated in the opposite direction to the roll. The centreboard, rudder and rig all contribute to this. Without these forces, a sailboat (especially a foiler Moth) would be a really wobbly thing! Incidentally, the longer the foils, the bigger this force is.
I was not initially in favour of T foil rudders as they added complication and de-natured the boat to a certain degree. However, after doing some sums when I was designing the SK4, it was clear that the foil made the boat faster (once above 6kts boat speed) and easier to sail. If the T is on the bottom, it makes no difference to launch or recovery. It can easily be retro fitted to any existing boat. So it was hard to come up with any reason not to use one on the E5 / E6.
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interesting discussion in the off topic nosiness of thin boats and T foil roll damping.
From our limited outings in the E5 so far I fully agree with the thinner bows is better argument. The narrow entry angle allows the boat to accelerate and decelerate more smoothly and reduces the magnitude of the pitching moment. this means that less buoyancy will be required to overcome the pitch. The narrow bow also gets rid of the bow wave (formed by fat boats) which increases the chance of pitching if in a displacement mode. The T foil also imprves pitchiness by as Ross says by anchoring the transom and moving the centre of pitch back. If the T foil is set neutral to the flow in a down wind leg it will try to drive the transom back in the water and correct the pitch. it is noticeable that if the t foil is set a little negative it lifts the bow and tames the boat which may be reassuring in choppy conditions before a race start. Not fast but safe.
The E5 is a tippier boat than the DOG but not as much as I was expecting. The roll damping effect of the T foil has overcome most of the effects of narrow forward lines, the added stability of the DOG's second chine and makes the boat much easier to sail than it would be without a T foil. In this respect only the T foil is the modern bilge keel. ;)
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I was not initially in favour of T foil rudders as they added complication and de-natured the boat to a certain degree. However, after doing some sums when I was designing the SK4, it was clear that the foil made the boat faster (once above 6kts boat speed) and easier to sail. If the T is on the bottom, it makes no difference to launch or recovery.
quite a few people at my club have asked me if the t-foil is of benefit on cheese due to the wider bows being pushed down into the water upwind and therfore creating drag. is this based on truth? ill have a non-t-foil rudder soon so will be able to test this but was wondering if any off the experienced people here have anything to add???
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I think that they are missing the point slightly John. The t-foil might be 'pushing the bow into the water', but you should still be trimming the boat with your body weight to make sure that its not dragging... you will just be further aft than you would be if the t-foil wasn't there.
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it was clear that the foil made the boat faster (once above 6kts boat speed) and easier to sail. If the T is on the bottom, it makes no difference to launch or recovery.
is it slower under 6kts then? drag more than lift benefit or something?
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As I understand it if the boat has less than 6knts boatspeed then the t/foil will create more drag. We have a rudder and a t/foil on Loco and in light airs will often sail with the rudder. it is a different story when you start moveing though as a t/foil adds not only speed upwind but also stability in both pitch and roll.
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it was clear that the foil made the boat faster (once above 6kts boat speed) and easier to sail. If the T is on the bottom, it makes no difference to launch or recovery.
is it slower under 6kts then? drag more than lift benefit or something?
John, it's all about lift to drag. You get benefit from the T foil when its lift to drag ratio is better than the boat's. The L/D of the boat is the displacement/resistance. A 0 kts, the displacement is say 200kg, but the resistance is 0. So the hull's L/D at o kts is infinity. The T foil on the other hand produces no lift at 0 knots. so its L/D is 0.
As speed increased, the hull's L/D decreases to an asymptotic value of around 7 at 15kts. Conversely, the foils L/D (when used at around CL~0.5) increases with speed to an value of 15-20+. 6kts is the cross over speed where the L/D of the hull and foils are about the same.
Now as Ross has pointed out, what you need to be doing is shifting load from the hull onto the T foil. For any given speed, the hull has an optimum trim angle. It is important that this is maintained. So you need to move backwards to load the T foil and to maintain the correct trim. As I've noted elsewhere, at 10kts, you can drop the drag by around 20% via the T foil. At speeds< 6kts, yes the T foil adds drag and should be set into neutral (no lift). It does however, reduce pitching. In very light winds, wave that cause the boat to pitch will actually cause the T foil to act as a propulsion device.... so don't throw it away just yet!.
There is an article I wrote for Y&Y and I think as a Cherub member, you can download it from the UK-Cherub site.
Hope this helps.
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thanks kevin that completely clears up my question :)
didnt know to set it to neutral at under 6kts though, thanks
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My feeling with a hull like the Dog is that when you get the trim right it will be quicker with the t-foil but if you are off trim you will be punished more than the post97 hulls with their finer bows.
To see Kevin's article go to the "Setup a T-foil Rudder" article in the tech section and click on the link at the bottom of the page. You have to login to the wiki as an association member for it to work
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I found that as long as we where twinning there was a big improvement with the T foil. It seems to make it plane high enough to keep the 2nd chine out of the water. If you sail it really flat with your weight as far back as you can and the T foil on enough so the bow is about an 2cm out of the water it is really fast, if it is not in this trim it is much slower. The T foil also helped maintain speed though the tacks.
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we weigh alot less though :(
weve found the same trim works aswell
once we got going we really blew away the 29ers yesterday in draycote!
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I found that as long as we where twinning there was a big improvement with the T foil. It seems to make it plane high enough to keep the 2nd chine out of the water. If you sail it really flat with your weight as far back as you can and the T foil on enough so the bow is about an 2cm out of the water it is really fast, if it is not in this trim it is much slower. The T foil also helped maintain speed though the tacks.
It is interesting that you say it helps through the tacks, I always worry that the back will sink more as you have to make a more positive forward movement as you move through the tacks and the speed drops.
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Edit: i had a momentary loss of english grammar! Please continue the discussion...