Topic : Winged rudders in National 12s

There is an interesting article at about Jo Richards and the effect of the winged rudder on his 12 design .  Good reading before the AGM. Also would our rules cope with his "big" jib and trim tab?
Nice picture of Sophie too - wonder what she was thinking about!

Posted: 30/06/2009 15:01:55
By: JC
Anyone care to copy and paste the article on to the forum for those of us who aren't subscribed to madforsailing.

Posted: 30/06/2009 16:26:27
By: .
If someone posted the article, then there wouldn't be any point in paying for the subscription and we would be liable for all sorts of copyright infringements. It is only £25 for the year, so the price of a decent Open Meeting, without the travel and hotel and beer and food.

Maybe Mags could ask through unofficial channels though ....

My understanding of the Rules, and I am sure that GGGGGG will correct me if I am wrong is that:

1. Winged rudders are currently OK, although action to make these illegal is being discussed at the AGM (please note Alex's comments in the Merlin Mag about voting, etc.) - I think it would be good to have Glen & Tom's opinions published prior to the AGM for discussion purposes. Otherwise, if you have an opinion or want to vote, asusming you are a full voting member of the Class Association, turn up at the AGM and make your presence felt, one way or the other.
2. Trim tabs on centreboards are allowed - anyone got an pictures of the mechanism to operate this via the jib sheets as I cannot work that out? The Madforsailing pic is a bit difficult to interpret.
3. Hanging the winged rudder is another discussion point. The Rules allow for rudder fittings but do not describe what these are, so I believe that gantries are allowed (it is afterall a rudder fitting), but I know that GGGGGG has a different opinion, which I am hoping to discuss with him over a beer or three before or after the AGM.
4. Changing ratios jib to main, moving the mast back, rocker aft, adding a "corner radius" to the foredeck to reduce windage, reduced freeboard - all OK and have been done at one stage of another, no one had joined them all together.
5. The only no-no that I can see is the jib. Our Rules only allow a 50mm offset from the luff to the extension line of the leech. The current Hyde sails that we have (and Glen uses) has this. That said, I cannot recall anything in the Rules that says that the leech must be straight or have a hollow, so leech round is OK if you can get the thing to hold up with only natural sail cloth stiffening.

As to whether anyone has the balls to do this on a new boat ... mmmm, no comment but we shall see after the AGM. One thing is clear from the reports is that Dead Cat Bounce clearly has provided the N12 fleet with some head scratching material to digest.

Reading between the lines (and I am probably wrong), the Merlin Class Association, specifically with the proposal on the table at the AGM for the T foil, is trying to decide whether these developments should be precluded from the Merlin or not. Personally, to put my cards on the table, I hope the proposal is rejected as none of the reasons for banning it put forward in the magazine are valid (although I can sympathise with the reasons behind it). I can understand a desire to maintain the price of second hand Winders and maintain that hull shape so that the investment by the front of the fleet is not thrown away, but the Class is not One Design and a fresh look at things, as Jo Richards did with his N12 is perhaps needed by the Class as a whole. The question is - is the class ready for this?

If anyone wants to disagree, bring it on. Please do not hide behind anonymous names and certainly do not bitch about this or that and then not turn up at the AGM. If you have an opinion (and I have others if you want) share them. Remember that the bottom line is that we love this Class and want it go from strength to strength, although we might have different opinions on the route that this might take.

Posted: 30/06/2009 22:26:16
By: Andy Hay - Enchantment 3386
OK.  I wish I was going to Salcombe so I could vote but I am not and I cant afford the time to go just to vote - thats a grumble :-)

Winged rudders will improve my sailing? I think not. I sail at Brightlingsea (3619 - no hiding) and I cannot see them working here. The first tight corner round the mud at low tide in a club race will cost you a fortune. We have a cherub sailor (sort of ex local) who tried it first time out (or was it second or third) the winged rudder got broken just after launching. I doubt he will try it again other than at high tide.

Yes my investment in a Merlin is precious to me. Second hand Winders (and others) are expensive boats compared to the RS400 I used to sail. I do not want, nor can afford, to have it suddenly devalued - were that to happen - neither I suspect could the rest of the embryonic Merlin fleet at Brightlingsea. A long time ago (25 years) I entered the class in 3136 at a time of lots of hull designs, I was not put off then because the designs in my eye seemed to be variants on a theme not radical step changes. I have no experience of the introduction of carbon masts etc. but would guess the cost involved in upgrading were somewhat less?

I have never been to Salcombe - I hope to one day soon holiday permitting - but from what I hear they would be rather dodgy there tacking up out of the tide.

Does the class want a boat that goes well at the Nationals but is impractical at many of the venues that are most strongly supported by the Merlin fleet?

So my vote - which wont be cast - is no to winged rudders and any other dramatic changes to the boat which probably makes me a Luddite in the class but I suspect in quite extensive company.

Posted: 30/06/2009 23:02:24
By: DaveC
I'll nail my colours to the mast too.  Albeit, as a non boat owner!  I think that developments like this should be encouraged.  The vast majority won't work, but those that do will gradually be absorbed into the class and improve it, as has happened for many years.

'One-off' boats for the champs have always existed, and they have had varying amounts of success. Ultimately though, the vast majority of owners will want to sail at the champs, and at Salcombe, and at Hampton etc. This will temper extremes.

Bring it on.

Posted: 01/07/2009 07:16:12
By: deepy
To move the trim tab on Joe’s centreboard there’s a line across the boat.  At each end of the line there is a block that the jib sheet runs through between the ‘normal’ jib sheeting block and an ‘extra’ ratchet just behind the normal sheeting block.

This line across the boat runs through two eyelets either side of the centreboard case, and when the board is put down a slot in the back of the trim tab towards the top of the board ‘catches’ the line. There are two plastic stopper balls, one on either side of the board.

When the jib is sheeted in the sheet goes tight between the two jib sheet blocks. This pulls the line to leeward, the windward stopper ball pulls on the tab and tacks the tab. In effect it’s automatic and doesn’t require any additional attention upwind.

Off wind there is a hinged ‘cap’ that locks the tab central. Apparently if left to its own devices life gets a bit exciting. Might not be such a problem in a merlin. I don’t know how fiddly it is or isn’t getting the line to engage in the slot when you put the board down. Sophie will be able to tell you.

The quality of the engineering of the foil and tab is very high. I expect that’s critical to making the whole thing work effectively.

Posted: 01/07/2009 09:03:00
By: 12
Jo Richard's Nat 12 was designed from the outset to carry a big T foil. He says that the hull shape is thus radically different to the current hot Twelves - it does not have the planing aft run that we know - flat rocker and rather wide. Instead, it has a lot of rocker and is very narrow. This puts a "big lump" in the water, which the foil sits in and exploits.
The dead cat is out of the bag - T foils win races: guaranteed.
If T foils continue to be allowed, tweaking a Canterbury Tales hull not an option. A radical new design or designs will be created, no doubt along the lines of 'Dead Cat Bounce', and the Merlin Class will move on (or not, depending on your opinion). Will there be a majority at the AGM willing to open Pandora's box?
As a designer, the thought occurs to me that the Richard's type of hull may perform very well as a river boat when sailing with a conventional rudder. So maybe fitting 'Passing Cloud' with a T foil would transform the old river boat into a Championship winner!

Posted: 01/07/2009 09:59:00
By: Keith Callaghan
surely there are better ways of improving the boat than adding a winged rudder. Reducing the weight would be better and fairer across the fleet.

Just think how much weed you'd of caught on sunday morning at Whitstable on the wing this last weekend

Posted: 01/07/2009 10:01:17
By: :)
just a couple of personal observations:

I understand that for a winged rudder to be effective, the hull shape needs to be modified - at least the aft sections.
What happens when you don't use a winged rudder? If using an ordinary rudder slows the boat, then it won't be competitive in the Silver Tiller - inland/river meets.
Perhaps we should allow a winged rudder - but require one to be used consistently throughout a year.
That would allow the development, but keep the older boats competitive for the series events - or where a winged rudder is a hindrance.

Last thought - I understand that a number of 12 designs were used as a basis for some Merlin Rocket designs - however the scale -up didn't give the same advantage - anyone confirm/deny this (hopefully with a full software package!)

Colin (3387)

Posted: 01/07/2009 10:18:02
By: Colin
There was certainly a couple of Merlin's designed by National 12 Designers, my old boat Meglo(3138) was one, this had far too much wetted surface area to be competitive.

Posted: 01/07/2009 10:22:40
By: Stuart Bates (3615)
Actually, I do not agree with the "will not work on restricted waters" arguement. On a river you sail at or below displacement speeds, only planing rarely, so wouldn't this fall into the T foil performance bracket? Yes, you will catch more weed as there is more foil to catch it on, but the guys that win will still avoid the weed.

There might be a further positive - the older more heavily rockered NSM2 generation (and before) might become more competitive with the modern flatties in a blow downwind as the T foil will mitigate the aft rocker. It would also allow lift at the back end, combined with the allowance of more rocker aft, all giving more of a chance for us heavier helms.

The current batch of foils on non-lifting boats (i.e. Moths) have the horizontal element mid rudder, so grounding out is no different from a normal fixed rudder scenario. We didn't hit bottom at Cookham with our fixed rudder, but we probably were cautious on hitting the banks. Of course half raising a lifting rudder to sneak along a bank is going to be an issue, but if we design a boat specifically for this activity is this not worse than designing for the Champs?

Keith - the proposed Rule change is not to open Pandora's box, whomever she is or was, but to try and close it before someone exploits it. T foils are allowed at the moment and will be until the Rules are changed. A T foil has been used (Mr King had one from Kevin Driver, I believe), and I know Kevin is keen to try further this development. Jo Richards has shown the potential of this device to a more mainstream audience than had previously experienced this. Of course, do not forget that Jo is an Olympic medalist and had a fantastic crew, so it may have been that he could have won Burton Week in a conventional boat anyway - who knows!

No one has thus far developed a T foil Merlin, in spite of the technology being available for many years AND it being legal. Maybe we are worrying about nothing, although bringing this to the table does increase the probability of someone developing a boat with this as an integral part. Once a boat is built specifically for a T foil, it becomes far more difficult to ban it later.

Mike Jackson developed a series of successful Merlins from his N12 designs, as did Phil Morrison, Jo Richard's Merlins (including Meglo) have not been very successful. Maybe the clinker hull negates some of the N12 theories, maybe the extra 2' and the Rise of Floor restricts the shape too much, I don't know. I am sure that Bim Daser could come up with something or even Jo might have another go if someone commissions him.

Posted: 01/07/2009 10:37:22
By: Andy Hay - Enchantment 3386
We all thought Joe would pick up weed, but his wings seem to be swept back enough that it doesn’t catch.

Some other wing designs do as expected.

Posted: 01/07/2009 10:38:36
By: 12
I think there are 2 issues the class has to look at.  The 1st is to do with if we think this will lead to the development of a boat that is not as good to sail - more difficult handling, instability in a blow, sticking in the light stuff.  The 2nd is about being divisive - will it lead to the development of boats that are only good in some venues not in others, specialist Champs and sea boats for example.  What Keith has to say is interesting and it would be good to know if Dead Cat Bounce is capable of winning a river meeting in the 12's.

Because the Silver Tiller and Salcombe are such a big part of the Merlin experience we are not likely to develop a specialist boat, but there is a worry over the potential outclassing of a hundred or more CT variants and what that would do to the health of the class overall.

Posted: 01/07/2009 11:07:39
By: Andrew M
PS Pandora (goddess of what?) gave Odysseus a box in which were contained the four winds, and like a fool he opened it.

Posted: 01/07/2009 11:41:47
By: Andrew M
Goddess of Mischief

Posted: 01/07/2009 11:48:45
By: alanf
Her box in the Merlin sense is open at the moment ....

Posted: 01/07/2009 11:49:42
By: Andy Hay - Enchantment 3386
Or not a goddess at all. But the 'first woman'. A certain consistancy here between greek mythology and the old testament, with the havoc caused by that apple!

Posted: 01/07/2009 11:53:35
By: alanf
Is it not a bit hasty to ban it before we have even tried it ? Surely the way forward should be to test a swept back design like Jo's with the horizontal foil at half height on a variety of old and newer Merlin designs in controlled conditions by a "design committee" made up of sceptics and proponents to see what its potential is ? At present the argument is not based on any empirical data but, dare I say it,prejudice and fear, never the best basis for decision making. Lets see whether its any good first, might be just the thing to make the vast majority of active club Merlins like mine more competitive with the more recent boats, which are lightyears away from my old wooden and overweight NSM4 or maybe not,BUT WE DON'T KNOW.  DON'T BAN IT, TEST IT !

Posted: 01/07/2009 12:13:39
By: Ricko3432
I seem to remember a gantry being fitted to a home designed/built yellow boat with very wavy planks being campaigned in the early 90’s – what happened to that?

Its all very distant but I think I last saw it at the Inlands at Bala, where I think Joe Richards turned up with a new design that was never seen again !

Posted: 01/07/2009 12:28:21
By: julian p
Re the above

Perhaps Joe chopped 2’of it and stuck a winged rudder on it

Posted: 01/07/2009 12:31:42
By: julian p
All for the "don't ban it", just not sure about the "test it" route.

This led us to ban fully battened sails (Weymouth early '90s) which were thought at the time to be better for heavy weights. Hindsight now suggests that fully battened rigs can be very controllable and give better control to lightweights when combined with a suitable rig, see Frank Bethwaite's second revision of the bible, sorry, Higher Performance Sailing. Anyway fully battened sails are rather off thread.

The testing of spinnaker poles held us to 6' poles for many years as one of the test venues liked to clip their pole under the deck onto the shroud and 6' was the right length.

I am sure that there are other examples.

Just beware of experimental error ...

I suppose we could put one on the back of Enchantment in time for the Nationals ....

Posted: 01/07/2009 15:31:44
By: Andy Hay - Enchantment 3386
The Merlin Rocket has form on testing going right back to the first spinnaker pole increase from 4'6" to 5' ("It improves the existing boat"). Transom flaps (Ned Sparrows dramatic demonstration at Plymouth that sold it.) Floating masts all those cold January days off Hamble (Didn't make any difference.) I would say do test it / try it, it it makes a serious difference and makes for a more flexible all up weight, it's the owners decision, if its slower no one will do it, but the door will be open and a development / restricted class will have another way to develop. If you didt' you would be sailing 4'6" wide boats with 25' wooden masts and cotton sails.
By and large testing has served the class well why not?

Posted: 01/07/2009 16:04:13
By: Ancient Geek
some of us still sail 4'6" wide boats with 25' masts and cotton sails!

Posted: 01/07/2009 16:54:25
By: John C
The ability to build adjustable winged rudders has been around for more than 5 years now, and in that time a high number of expert sailors who have far too much money......have not used one.

Can we infer anything from this?

Posted: 01/07/2009 22:40:55
By: Mags
Laziness? Complacency?

Posted: 01/07/2009 23:20:52
By: ..
Yes Keith, I like the idea of 49 year old 'Passing Cloud' winning the Championship!

Posted: 02/07/2009 08:19:06
By: Robert Harris
Most of the points have already been answered but for what its worth from the front end of what was an amazing boat to sail;

- Trim tab: To get the line to engage was a little fiddly but I recon the gains outweighed the hassle
- Stability: It was the most stable 12 I've sailed and very forgiving (in all directions)
- Weed: Not a problem any more than for anyone else due to wings being swept back and up

I'd say that all of the developments contributed at some point to our performance across the variety of wind strengths, and in combination with Jo's knowledge and understanding of them, the results speak for themselves.

As an aside I wouldn't want to sail it with a winged rudder on anything other than open water - corners were not our strength.

Posted: 02/07/2009 08:31:20
By: sophie
REf. Colin's comment about scaled up National 12 designs not being successful, I stand to be corrected but wasn't September Girl a derivative of China Doll?  And from this lineage came Satisfaction, Smokers Satisfaction and NSM ...

Posted: 02/07/2009 08:58:34
By: David
And there you have it really, do we want a development that will  improve stability and handling (but this is not nearly such an issue for the Merlin as for the 12) but make it more difficult to short tack on restricted water.  Going back to the longer poles argument, the trials of poles were before my time but what happened was that the class DID adopt longer poles, just not the longest that were being trialled.  When the issue of poles came up again in the 90's the present length came in with very little dissent, ditto the changes in spinny measurement.

On just the physics of it, there has always been a problem in the 12's of getting adequate weight carrying capacity and downwind stability and performance out of a 12 ft waterline, which is less of an issue with the extra 2 ft we have. The winged rudder is likely to be much more helpful in the 12 as it addresses just these issues.

Posted: 02/07/2009 09:05:05
By: Andrew M
I think the cornering of DCB was as much to do with the low freeboard than the winged rudder. The Paradigms have no issue with roll tacks, and are very fast in restricted waters. The word on the street is that DCB would not work without the wings, even in light winds, unlike the Paradigms. I don't understand why, but Gavin may be able to answer. He is considering a more light wind orientated hull shape for the next version of his boat, using the wings to reclaim the energy in higher winds. Thats quoting him, so dont ask! I think a DCB derivative with more freeboard would probably be better round the corners. Graham Camm thought so too after trying DCB this weekend. He also commented it was the most stable N12 he had sailed in a F6. High wind stability may also be a big step forward in the shorter boat. I must admit, I didn't like the development of these rudders on the 12, but now I have seen them working, I am tempted to try one.


Posted: 07/07/2009 20:47:27
By: Ectopic 12
Just to add my opinion as some one that doesn't yet own a Merlin but who is looking... all this talk of what might be the next step up in design is putting me off. 
I know that this is a development class but just as people are convincing me that an old boat wont win the nationals but is still competitive at club events, I hear all this talk about moving the goal posts once again.
If I had a vote, which clearly i don't, I wouldn't be allowing it just yet. Lets get the worst of the recession over and let people feel good about spending money on new equipment before we rock the boat so to speak!

Posted: 16/07/2009 23:15:01
By: Ian
don't worry they are banned now after the agm a couple of days ago.

Posted: 17/07/2009 01:50:13
By: ld
To quote Frank Bethwaite in "High Performance Sailing", page 250:

"An economic note is of interest. Those who argue against a development class usually cite that whenever a better design is developed, the value of the obsoleted boats will fall. In this case the excitement generated by the breakthrough design was such that it attracted many to the class, and the resale value of the obsoleted boats went up, not down, due to the increased demand."

OK, at the time there was not the plethora of other classes, but this was a fervent of development in the NS14 class in Oz, and a new hull with flexible wingmast arrived. This boat won the Oz & NSW Championships, the later with a second and five wins in a 100 boat fleet. Sounds familiar doesn't it?

No matter, decision made by the majority attending the AGM.

Posted: 17/07/2009 07:04:49
By: .
The thing's not our idea, it's not our development, It's Jo Richards idea and we would just be copying in some desperate fashion an idea from another class.sad but true.Well done Jo you have been innovating for years long may it continue. Quite a storm in a T cup.

Posted: 17/07/2009 16:15:58
By: Land locked of London


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