James,

I respect this.

Allow me to reply your last post with a few additional comments.




That is a argument I can react to. F16 racing in Aus and for that matter in other parts of the world is grown and developped by having multiple builders in the class. It gives the class both stability and a increased numbers if all builders promote their product next to the class as a whole. This is of course evident. In order to keep builders in the class or attract more builders in to the class we are faced with two issues :

-1- Some builders do not want to be dependent on a remote extrusion company as a source of their mast.

-2- Some builders want to maintain a more firm hold on the Goodall Superwing sharing deal.

Both necessitate allowing carbon masts in the class.

Of course we can do that at tipweight = 6.5 kg, however for some reason 30 F16 boats do not comply with this part of the rule.

Don't ask me how, because I was under the impression they were compliant till 2 month ago. But it turned out they aren't and probably never were. So pretty much we have to either ban all these boats or lower the tip weight to 5.5 kg. Pretty much 5.5 kg is pretty close to what appears as the minimum realistic tip weight anyway, so if we are going to lower to this level why not remove the rule altogether ?

This last option is both favoured by a good portions of the sailors, if my perception is right, and is not feared by the builders. Both Blade builders will continue to use the Superwing section and so too will AHPC.

I also found that some sailors, like the guys in Switserland want carbon masts.

It will be evident by opening up the carbon mast rule or deleting it both builders and new customers will be more happy. This will translate itself in more sailors and as such as improved racing over time.

Pretty much the expected growth of opening up the rules is bigger than any loss expected due to NOT maintaining the current rule. This is issue 1.

Issue 2, The F16 rules are "spirited" around the concept that only important factors are limited. The current mast tipweight rule doesn't seem to live up to this criterium. It simply doesn't appear to ban a clear inequality in the way that limits on width or sailarea do for example.

This issue is of course all about numbers and engineering I understand that. However before we all vote on the rules we need to try to understand that there is hardly a sound scientific basis supporting a perceived inequality between boats when lowering mast tipweight. The case behind width is very clear, so to behind limits on sail area and mast length. The case behind the tipweight is largely a faith-based one. What we do have is the fact that the boats with the alu mast certainly do not feel hampered by it (diving or having slow dying oscilations). Not in the way I can personally attest to when looking at the Nacra 5.5, FX-one and other alu masted designs. So what we have ended up with is a rule that both fails to have a clear scientific basis and fails to have a clear empirical basis.

So I repeat : The current mast tipweight rule doesn't seem to hold up to the ultimate F16 criterium for class rules.



3rd issue; as a class chairman I rather organise the checking of boats with fewer limits. And measuring the mast tip weight is very much a measurement that requires both time, manpower and space. This is all fine if we get alot of equality in return but it is just foolish if it tipweight doesn't really matter much.

4th issue : In the past one of the main reasons to have the tip weight rule was to garantee carbon masts that would hold up to rough F16 sailing. Now a certain builder broke a few masts will experimenting with carbon masts but their current 5.5 kg tipweight masts seem to hold up pretty well. A few homebuilders are sailing with underweight masts right now that are made compliant with lead or timber glues inside the top of the mast. Arguably both modes do little to inceases the resistance of the mast against abuse or harsh conditions. So the rule is failing in its goal of garanteing dependable mast. Especially now as little over 30 boats (25 % of the class) will all have to put batteries up their mast tops. It will be a little awkward to do so because that "would make their masts more dependable in rough conditions"

I agree that this issue of the 30 non-compliant boats is something I'm not happy. But that is not something for this public forum to discuss in detail. Were the tipweight a very important factor than the class would move to ban this non-compliance and force everybody to become compliant. However, it appears that this tipweight is not a serious factor if one at all, so the question becomes do we still ban these 30 boats ? Do we ban them on something that may well be insignificant. Everybody must make their own appreciation of this. But remember that ones you'll be on the receiving end of such a vote, so it will be wise to really consider this tipweight voting from the perspective of the others. It will be very tempting to vote down anything that doesn't hurt you. But I fear we'll end up voting down the oversized jib dispensation for the Taipans in the next vote. And this is the reason why F16 class does not have a "2/3rd of the class forces a decision" setup.


5th issue ; Their is movement on the front of carbon masts. There are some initiatives to have these produced at much reduced prices. It is possible that carbon masts end up being about as expensive as an Alu mast. As good as all other classes that mean a thing internationally are moving in the direction of carbon masts. Tornado, F20's, A-cats, all except the F18's. Also part of our direct competition is moving in the direction. It may turn out to be vital for us in the long term to open up our rules to allow us to follow the trend when the need to do so arises. This is of course very important in growing our class and F16 racing everywhere. No racing is as unattractive of racing in a dead or dying class. It may not be perfect but a vital class is always to be prefered over one that is losing the battle with the competition. Even if some inequality exist between tipweight this may well be worth accepting if it garantees continued vitality. A hard issue to make judgement upon, I understand, but nevertheless something that must be looked at really hard.


6 th issue ; what is uncompetitiveness really. 90 % the fleet will not change position relative to other sailors when their boat for some reason is 1 to 2 % slower OR faster than the others. That is simply the case in reality. Personally I can't not come close to either Fabio, Andrew or Jennifer even when sailing a Tornado and my life depended on it. For this part of the fleet it doesn't matter at ALL wether or not a thing like tipweight makes a noticeable difference or not. Competitiveness in their league is totally determined by sailing skills and the amount of practise they are willing to put in. So the question really becomes how important is any small inequality with respect to the top 10 % of sailors. These guys tend to experiement largely with sail cut and trim anyway and often buy new suits of sail regulary. They buy polyester nylon spinnakers and 3D molded sails if they can gether the money for it. They sail with the latest foil shapes and what not else. We can't realistically ban all of this and for these guys it is a piece of cake to buy a carbon mast if they feel that makes them competitive for 1st place. I personally have a really hard time explaining to a whole class of sailors how this is unfair to them, ASSUMING that a noticeable difference exists which we simply can't proof right now ? First, 90 % of them isn't competitive with the top 10 % of the class at their level of commitment anyway and secondly a good tack or proper start is enough to fully compensate for any small inequality if ever such a thing exist. And this is when we don't even look at differences in crew weight. All classes currently accept differences in crew weight of at least 15-20 kg's without much fuss, but we feel that some other factor possibly giving the same amount of inequality or less is unacceptable. This is simply not consist, actually it is being subjective. So the question really is what is competitiveness ?

It is indeed my personal opinion that we often make too much fuss about things that don't really matter much, if at all. On both engineering principles and the feel of sailing with the superwing mast I truly feel that tip weight is a mute point when racing F16 designs of different make and with different crews against one another. In any way, alot more mute than say sailarea or mast height.

And to end this post the last issue :

7th issue ; after close examination I came to the conclusion that an alu mast can be designed to have the same weight to stiffness ratio as a carbon mast. Simply by adjusting the ratio between enertia of the crossection and the density of the material. If you are using ribs inside the mast to alter the crossection enertia than you won't alter the overall weight of a given alu mast. Note how this means that you can have any ratio of weight to stiffness in an alu mast. By scaling the cross section of the mast for this optimal cross section shape with ribs you can end up with any bending curve. So, with proper designing you can get a very optimal alu mast section. Something I think the Superwing mast achieved. This only leaves the typicall lighter weight of carbon mast in the way of overall boat weight or improved dive recoverey as the only factors that could favour a carbon mast over an alu one. Noting that in the F16 format the difference is pretty much limited to 3 kg and the Alu masted F16's don't have any issues with dive recovery at all makes any NOTICEABLE inequality between carbon mast and alu mast very unlikely. Let alone an unacceptable inequality.


Now several sailor may have read all this and still decide that they think tip weight a major factor in performance To them I say what do you want me to do about redesigned alu masts or carbon mast with the full tip weight but different crosssections ? To them I say, the feeling of uncompetitiveness is an issue that is far better solved in your own mind then by any class rules. That and losing some 15 kg of body weight and train sailing at least 15 hours a week.


Wouter


P.S. Sorry about this essay James, but how else can I explain it ?