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Q 3 : What do you want covered in the rules ? #678
07/12/01 07:36 AM
07/12/01 07:36 AM
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Wouter Offline OP
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Introduction :
<br>
<br>We all have opinions about what should have been outlawd and what not. what is fair and what not and what should be regulated in a particular manner.
<br>
<br>The question :
<br>
<br>Where do you see a pitfall ? What do you think should be regulated in the rule framework and what should not. And how such it be regulated or deregulated ?
<br>
<br>Please give a complete reasoning in your reply.
<br>
<br>Wouter<br><br>


Wouter Hijink
Formula 16 NED 243 (one-off; homebuild)
The Netherlands
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Re: Q 3 : Carbon Masts, Pole length,Beam [Re: Wouter] #679
07/13/01 01:53 PM
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I think most of what I have below is already covered but interested in peoples opinion regarding subject line.
<br>
<br>Length, beam , min rigged weight, jib size, rated mainsail area,gennaker luff max length, gennaker max size, pole length past the bows (as per texel ratings, I think 800mm)
<br>
<br>I like the way Rated mainsail area takes care of mast length.
<br>My preference would also be mast material.
<br>I'd like to avoid carbon masts because of relative cost to aluminium.
<br>Just my opinion- very interested to what others think.<br><br>

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I know that the voices in my head aint real,
but they have some pretty good ideas.
There is no such thing as a quick fix and I've never had free lunch!

Carbon masts, Pole length,Beam [Re: phill] #680
07/13/01 08:36 PM
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In order :
<br>
<br>Length : I'm happy with mast to sailarea dependency formula as used in measurement system. My preference to genaker pole Pole length : Texel/FFV/ISAF rule of 0,8 meter passed bows, But than again I'm in a Texel area. Width of boat ; everything goes as long it is trailorable horinzontally all over the world = max 2.55 meters (?)
<br>
<br>min rigged weight: I choose the phychological boundery of 100 kg's ready to sail 2-up. Still minimal rigged weight is of not much important as equality is fixed by formula in which weight is a variable. As long as the performance prediction is equal to the F18 class. The solo platform will come in a little lighter. Why a minimum weight at all, to garantee thatolder boats stay competitive and to give some garantee of constructial robustness. Furthermore I have let myself be inspired by the fact that this weight limit can be reach by building in Timber. This will add to the low entry into the class.
<br>
<br>, jib size: I would like to see a minimum size and a maximum size
<br>
<br>, rated mainsail area : All for it
<br>
<br>gennaker luff max length: Need more thinking time
<br>
<br>gennaker max size : For now just fix it at 17 sq. mtr.
<br>
<br>, pole length past the bows (as per texel ratings, I think 800mm)
<br>
<br>
<br>>My preference would also be mast material.
<br>I'd like to avoid carbon masts because of relative cost to aluminium.
<br>>Just my opinion- very interested to what others think.
<br>
<br>I'm in doubt. The HT in F16 HT stands for High Tech. Can we honestly outlaw carbon masts then ? Aluminium is much cheaper that is true. We might even need Carbon mast to get the boats down to 100 kg's sail ready weight. On the other hand I've heard Boyer say that the aluminium mast on a Taipan 4.9 is only marginally lighter than a carbon one. I don't know how true this is.
<br>
<br>Wouter
<br>
<br><br><br>


Wouter Hijink
Formula 16 NED 243 (one-off; homebuild)
The Netherlands
Re: Q 3 : What do you want covered in the rules ? [Re: Wouter] #681
07/15/01 10:06 AM
07/15/01 10:06 AM
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Stewart Offline
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Wouter,
<br>I would prefer to see as few restrictions as possible..
<br>Max length, max width then either max mast height, or max luff length.. or possibly max sail area.. allow single or multiple crews but if one nominates as a single (or double) the regatta must be sailed as that..
<br>as for genacker. just rate the max luff length..
<br>
<br>I believe the 100 kg min is too high.. Firstly you wish a High Tech class then you suggest it should heavy enough to encourage be lowish tech construction.. Seems a tad od.. Perhaps the class should be F16 MT where M is moderate ..
<br>
<br>If someone wishes to build a nomex carbon hull with M18 style rig then I would suggest its what we should allow..
<br>What about a solid wing mast with a genacker? It would be HT surely.. Would this be legal?<br><br>

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Re: Q 3 : What do you want covered in the rules ? [Re: Stewart] #682
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Stewart,
<br>There is a lot of truth in what you say. Marstrom is probably the only manufacturer currently equiped to make
<br>'high tech" boats.
<br>
<br>In this case it is a name to set 16ft boats of higher performance apart from the rest.
<br>
<br>My concer regarding the min weight is that you create an arms race that very few can afford to participate in. (Not much point being the only F16HT on the water.) Even the A class has a min weight to prevent this type of thing.
<br>
<br>I think 100kg is a reasonable weight considering the boat may need to take the loads of being sailed 2 up with a jib and spinnaker in addition to the main.
<br>The A class has a min of 75kg and does not have to take the loading that comes from the extra crew, spinnaker and jib.
<br>
<br>As far as a "solid wing mast". Appart from several C class cats built specifically for the "Little Americas Cup".
<br> Bob Forbes had one built back in the 80's for a NACRA after seeing Wild Turkey "run away and hide" in the US 18sq championships. They are the only two that I know of outside the "LAC". Well this didn't take off in the 80's and I don't see why it would do any better now. Allowing this is not a good way to get a 16ft Formula off the ground.
<br>
<br>The idea is to create a Formula Class for the 16ft boats that are capable of competing against F18 boats on a boat for boat basis.
<br>
<br>I think this is a worthwhile objective and the rules that are finally decided upon should be considered in this context.
<br>
<br>This is just the way I see it.<br><br>


I know that the voices in my head aint real,
but they have some pretty good ideas.
There is no such thing as a quick fix and I've never had free lunch!

Steward [Re: Stewart] #683
07/17/01 04:57 AM
07/17/01 04:57 AM
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Wouter Offline OP
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Steward.
<br>
<br>Going back in September to do some more skiff sailing (also 49-er) in Greece. I've got a dedicated and almost fanatical crew; just what you want on a skiff hey.
<br>
<br>Anyway with respect to the points you raise.
<br>
<br>>I would prefer to see as few restrictions as possible..
<br>
<br>This is also the intend of the F16 HT group, however I think that the views differ on what is poossible and what isn't. Phill is right in his comment that this is intended to start a viable class. This will surely limit All-Out High Tech approach. That approach is left to the truelly Open class. Why deregulated everything but still fix a length of 16 foot ? Wouldn't 20 foot and light weight be even more high tech (M20 ?). Where must the boundery be drawn. It is also the intend of the F16 HT to present a good alternative to the other classes with respect to money. The BIM 16 can in EU be bought for 40 % of a new F18 and both boats perform the same ! This is also High Tech, getting the maximum out of a limited boxrule including cost to performance ratio.
<br>
<br>>Max length
<br>
<br>This is a necessacity to be able to form a class of equally performing boats. Even the small boat development classes of all time 18 foot skiffs and A-cats have opted for a few restrictions. This is also done to stimulate development. Personally I believe that Technology developped faster when more people are capable of participating. No -restrictions will stiffle small improvements for the big bucks guys will just overpower all smaller improvements by entering with a all carbon and disposable boat.
<br>
<br>
<br>> max width
<br>
<br>Is NOT regulated. Boat can be a wide as you want too as long as it is trailorable. The 16 foot boats will never reach this 2,55 meter width however for this would imply more power in the boat that the 16 foot hull length can ever prevent from pitchpoling. The optimal ratio between width and length probably is less. Otherwise the Taipan and Bim would have been made wider.
<br>
<br>> then either max mast height
<br>
<br>This is also NOT regulated. Same reasoning as with boat width. Ratio sailarea to mastlength is fixed via the rated sailarea formula which gives a predicting of truelly developped sailpower. All boats will therefor have the same thrust. Some may devellop this more efficiently than others. There is room for experimenting and development here.
<br>
<br>> or max luff length.
<br>
<br>Is NOT regulated. Reasoning as point above. Only genaker luff may be regulated but thuis point is still open for debate.
<br>
<br>>> or possibly max sail area..
<br>
<br>Is rgulated by ratio, see two points above.
<br>
<br>> allow single or multiple crews but if one nominates as a single (or double) the regatta must be sailed as that..
<br>
<br>I'm a little confused but think this is implemented as such in the (draft) rules we have right now. F16 HT regulated both 1-up as 2-up sailing and I feel the boat is too small for a crew of three.
<br>
<br>>>as for genacker. just rate the max luff length.
<br>
<br>Do you mean without specifying the maximum area ? What would you feel is a good lufflength to fix ?
<br>
<br>> I believe the 100 kg min is too high.. Firstly you wish a High Tech class then you suggest it should heavy enough to encourage be lowish tech construction.
<br>
<br>> Apart from the A-cat class and a few 13 to 14 foot cats, no cat has gone under 100 Kg's. Taking the A-cat as a lead :
<br>
<br>A-cat weight = 75 kg's
<br>Genaker setup = 6,5 kg's
<br>jib setup = 4,5 kg's
<br>
<br>minimum weight F16 HT without reinforcements = 86 kg's. An A-cat with a jib and genaker and double trapeze will be likely to break in the heavier airs, so I think that ONLY 14 kg's of reinforcements is not much to make it strong enough in 6 beaufort (25 knots) which will be the maximum windstrength for F16 HT races. I agree with Phill here, 100 kg's is needed and is already difficult to achive. In theory we could have gone a little lower say 95 kg's but then we would have no grandfather boats around which to start the class at all. Now, when no class than no-one will develop the 95 kg's F16 HT boat at all. So what is wisedom, we opted for the 100 kg's as a compromise, it is a few kg's lighter than the grandfather boats are and not to light to make them immediatly uncompetitive. And ofcourse 100 kg's is just about what can be reach by timber homebuilding.
<br>
<br>>. Seems a tad od.. Perhaps the class should be F16 MT where M is moderate ..
<br>
<br>Maybe, Still Steward I think that alot of your points are in fact left open in the F16 HT so it mght deserve the HT extention again. Even the 18 foot skiffs and A-cats are regulated to the same degree so it can;t be all bad, right ?
<br>
<br>>>If someone wishes to build a nomex carbon hull with M18 style rig then I would suggest its what we should allow..
<br>
<br>These will be one of boats just like the supercats. They are to extreme to create their own class. No class , means no buyers, no buyers means no development. This is the paradox that we are trying to overcome in the F16 HT. It may not be the ebst setup but it may well be the best setup we've got right now. Without it we keep getting the 150 kg's inter 17 and FX-one and 180 kg F18. The F16 HT will outsail these, isn't that pretty High Tech already for a smaller 16 foot boat !!
<br>
<br>>>What about a solid wing mast with a genacker? It would be HT surely.. Would this be legal?
<br>
<br>Probably not but we're still discussing it. Pesonally I feel that solid wingmasts are for millionairs and there are not enough sailing millionaires that are interested in small cats to base a class upon.
<br>
<br>But thanks for your reply Steward, I hope to see a reply on my comments of you.
<br>
<br>Wouter
<br>
<br>
<br><br><br>


Wouter Hijink
Formula 16 NED 243 (one-off; homebuild)
The Netherlands
Re: Q 3 : What do you want covered in the rules ? [Re: Wouter] #684
07/17/01 03:05 PM
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john p Offline
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I think that the rules should be as simple as possible, I think that the main things to regulate should be weight, length, beam, mast height/main area (the rated sail area system seems fine to me) however I feel that a maximum mast length should be given, jib area, spinnaker area. I don't think materials should be regulated, The high tech part of the rule should be protected, it may be that carbon masts are more expensive than Aluminium at the moment but prices are coming down and soon all masts will be carbon, if you prohibit carbon now you will end up having to let it in later and that will make a lot of boats obsolete.
<br>
<br>look at the progress that the Aclass has made over other boats of its age, if you keep the regulations to a minimum then you allow manufacturers to make progress, this class by virtue of its name needs to be able to stay towards the forefront of developement, this does not mean that it will become an arms race, the weight we are proposing is relatively easy to build to without materials being too exotic.
<br>
<br>
<br> <br><br>


John Pierce

[email]stealthmarine@btinternet.com
/email]
F16 HT limitations [Re: Wouter] #685
07/17/01 04:52 PM
07/17/01 04:52 PM

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Okay,
<br>
<br>My views on the topics are :
<br>
<br>I'm satisfied with the draft rules as they are being proposed now. When are they going to be put online in the broader sense ? I agree with Steward and John to stick to a limited set of restrictions and to allow as much development as possible. On the other hand I go with Phill in trying to prevent obvious dangers to the fletchling class. I feel that the rules may need reformulation but that the general idea is sound, but then again I'm not an experimenter in real life nor do I posses the knowledge and experience of some of you.
<br>
<br>On the carbon issue, I side with the people opting to allow carbon masts. I think that at least proven techology should be allowed under F16 HT. It should at least start out from the current "cutting edge" in catamaran technology. Carbon masts do definately fall under this describtion. It would be Medium Tech to not allow them (Steward). Having said this I will probably start out with a aluminium mast to cut down on the costs to get in the class. Then again BIM offers a great carbon package with their BIM 16 if their F16 HT price is in the same ball park then I won't hesitate a minute and go carbon. I also prefer carbon from a safety point of view.
<br>
<br>Do we know already wether 17 sq. mtr. is the maximum genaker area allowed under Texel for a 1-up boat.
<br>
<br>Anonimous4
<br>
<br><br><br>

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Hello John, good to see that you've succeeded ... [Re: john p] #686
07/17/01 05:23 PM
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Wouter Offline OP
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Hello John, good to see that you've succeeded to log on.
<br>
<br>Welcome to the forumboard about F16 HT. I assume from you post that you've read the draft rules. Otherwise you wouldn't know what the : " rated sailarea" concept was. I saw the report on the Stealth performance with respect to F18's and international tornado on the web. Sounds very much like waht we're trying to achive.
<br>
<br>One question : why do you feel the need to regulate a maximum mast length. Would light air performance self- regulate the maximum mast length ? (I assume that brute sailarea is king in light air, a ver long mast would lack in these conditions)
<br>
<br>I assume that you're for allowing Carbon masts and that you are satisfied with 100 Kg's minimum weight for the 2-up configuration. Just right in between very high tech and low tech. Am I correct in these conclusions ?
<br>
<br>Wouter<br><br>


Wouter Hijink
Formula 16 NED 243 (one-off; homebuild)
The Netherlands
Re: Hello John, good to see that you've succeeded ... [Re: Wouter] #687
07/17/01 05:42 PM
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Wouter
<br>
<br>generally speaking, high aspect ratio sails perform better in light airs, low aspect go well in the breeze, howevere i'm not too sure how the sail area reduces with mast length using the formula for rated sail area. But if you look at the A class they use longer masts than we are proposing with narrower boats and less weight to hold them up, I think you may find that if you don't limit mast size they may grow and grow as people develope the boat, personally I'd cap the length to stop obsolescence in this area.<br><br>

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John Pierce

[email]stealthmarine@btinternet.com
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Re: Hello John, good to see that you've succeeded ... [Re: Wouter] #688
07/17/01 05:51 PM
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I agree with 100kgs min weight I think it is the right balance between high tech and practicality. <br><br>


John Pierce

[email]stealthmarine@btinternet.com
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Reasons is ... and what is a good max size mast [Re: john p] #689
07/18/01 04:49 AM
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Wouter Offline OP
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>> howevere i'm not too sure how the sail area reduces with mast length using the formula for rated sail area
<br>
<br>Ohh, that is simple the formula is such that the benefit that you get from a longer luff mainsail is corrected by making the maximum allowed mainsail sailarea smaller.
<br>
<br>Go to the Texel rating calculator and ply with the number s of luff length and mainsail area. Try to keep the rated mainsail area equal or less than 13 sq. mtr. you'll see what i mean.\
<br>
<br>link :
<br>
<br>http://www.geocities.com/kustzeilen/excel/tr_calculator.xls " target="_blank"> http://www.geocities.com/kustzeilen/excel/tr_calculator.xls
<br>
<br>The rated sailarea formula is fix in its outcome and it has only two basic parameters which are linked together to create that fixed outcome. So if one increases the other must descrease.
<br>
<br>Okay, John what would you consider a good limit in mast height ?
<br>
<br>Wouter
<br><br><br>


Wouter Hijink
Formula 16 NED 243 (one-off; homebuild)
The Netherlands
Extra comments [Re: Wouter] #690
07/18/01 04:59 AM
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Example : Taipan 4.9 luff is 8,02 and mainsail including mast is 14,58 now when the mast is increased to allow for a 8,5 luff length the max allowed mainsail is decreased from 14,58 to 14,1 sq. mtr. or 0,48 sq.mtr . less.
<br>
<br>THe point you make about high and low aspect sail is that under the assumption that both sail areas are equal, becuase than I totally agree with you than even higher aspect sails are to be preferred in nearly all instances. But the rated mainsail area formula was proposed to counteract this without actually limitting boat parameters. The limitation is intended to be optimal performance itself. When you go to low aspect because you want a big sailarea than you'll loose out unacceptally in one set of conditions and when you go to high aspect and accept a small sailarea than you'll loose out in another set of conditions. This will make development self limiting without making the rules too strict. Do you think, with your experience<br><br>


Wouter Hijink
Formula 16 NED 243 (one-off; homebuild)
The Netherlands
Re: Extra comments [Re: Wouter] #691
07/19/01 05:32 AM
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Wouter, I agree I thimk that this will become self limiting, although it possibly gives a vast range of sail/mast combinations, bearing in mind with the longer mast you can have a longer spinnaker luff length.
<br>
<br>I think you may end up with a bit of an arms race, certainly in the beginning, up untill the point where developement of the boats finds the 'self limit'. the cost of this will be bourne by the folk who end up with obsolete kit.
<br>
<br>Personally I would fix the mast length (8.5m) seems about right, then at least there is only sail developement to pay for, and sails are a consumable item anyway, a boat owner would hope that their mast would last the life of the boat.
<br>
<br>On another issue I have been running some figures through the texel and isaf handicap formulae: to get a 16ft boat weighing 100kgs with a 17sqm kite to rate the same as an f18 you end up with main around 15.5 sqm (with mast) and jib about 3.2sqm.
<br>
<br>Now we sail the stealth with main 13.75 m and jib 4.9 m, not much difference in all up area, but the boat is only 2.29 m wide, increase the beam by 300mm and the righting moment goes up by about 13%, our crew weight is 148kgs (325lbs), I wonder if we may be designing a boat for lightweight crews, just a thought has anybody looked at this?<br><br>

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John Pierce

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John's proposal of 8,5 m max mast will ban BIM 16 [Re: john p] #692
07/19/01 11:14 AM
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John's proposal of 8,5 m max mast will ban BIM 16, of which the mast is 9 m. I would therefor push for a max set at 9 m if a max is set. Personally I would like to see no max and see the scene sort out what the most effective mastheight is. Just like was done in the A-cat cirquit. I feel that there could be an arms race like John predicts, but that the "cost to possible gain" is such that the impact is very limited due to the workings of the Rated Sail Area formula. I feel that the first bucks will be spend on getting a perfect 100 kg platform before any money is spend on optimizing mastheight. The gains with respect to the weight savings are clear and well defined; the same can not be said about the mastheight. In other words, I feel that designers will be hesitant to spend alot of money on a "maybe" gain that may well not be worth the money at all. This should be enough to stop an uncontrolled arms race and on the other hand open the door enough for controlled development.
<br>
<br>In summary, my answers :
<br>
<br>* I opt for letting the Rated Sail Area formula regulate mastheight.
<br>
<br>* If mastheight is limited than at least at 9 m in order to include BIM 16 and to have some room for optimizing the rig and genaker.
<br>
<br>Anonimous4
<br>
<br><br><br>

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Re: Extra comments [Re: john p] #693
07/19/01 06:27 PM
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Wouter Offline OP
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John,
<br>
<br>>> bearing in mind with the longer mast you can have a longer spinnaker luff length.
<br>
<br>While Thinking about your comment I'm inclined to risk it on the mast heigth and to fix the draw of the genaker as Steward proposed. This will defuse the biggest danger (genaker luff length) and satisfy the wish of having as little restrictions as possible as to allow for development.
<br>
<br>Somehow I don't fear an arms race on mast height. Only experimenting to proof the validity of the rated mainsail area formula will show wether an arms race is really to be feared.
<br>
<br>
<br>>>Personally I would fix the mast length (8.5m) seems about right, then at least there is only sail developement to pay for, and sails are a consumable item anyway, a boat owner >>would hope that their mast would last the life of the boat.
<br>
<br>As remarked by a gorupmember , this will put BIM out of the F16HT. How high isnthe Stealth mast ? For the Taipan and BIM are quite close to one another.
<br>
<br>>>On another issue I have been running some figures through the texel and isaf handicap formulae: to get a 16ft boat weighing 100kgs with a 17sqm kite to rate the same as an f18 you end up with main around 15.5 sqm (with mast) and >>jib about 3.2sqm.
<br>
<br>Do you have the ISAF formulae ?!? Can you send them to me please. I've been trying to get them but no-one has responded to my e-mails yet. You don't have the FFV formulae as well do you ?
<br>
<br>BTW , you've used the 8.5 mast = 8 m luff in the formulae
<br>
<br>Texel gives 14,85 sq.mtr. by 8 m luff and 3,35 by 4,7 m luff
<br>Anyhow, It would very much like to fo the check calculation in ISAF or FFV too.
<br>
<br>>>Now we sail the stealth with main 13.75 m and jib 4.9 m, not much difference in all up area, but the boat is only 2.29 m wide, increase the beam by 300mm and the righting moment goes up by about 13%, our crew weight is 148kgs (325lbs), I wonder if we may be designing a boat for lightweight crews, just a thought has anybody looked at this?
<br>
<br>I'm confused by what you say in your last sentence. Can you clarify please.
<br>
<br>Wouter
<br><br><br>


Wouter Hijink
Formula 16 NED 243 (one-off; homebuild)
The Netherlands
Re: Extra comments [Re: Wouter] #694
07/20/01 12:55 PM
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Joined: Jul 2001
Posts: 183
If a mast limit is set it should take account of the existing boats, i.e. set it to the length of the longest mast. The Stealth has 8.4m mast
<br>
<br>My comments on the weight carrying ability are that it seems to me that f16ht will end up with similar sail area to our Stealth R for which a crew weight of around 145kg is best. f16ht will be a foot wider that the Stealth so it should need less weight to keep it upright. <br><br>

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John Pierce

[email]stealthmarine@btinternet.com
/email]
Alot of math, here goes ! [Re: john p] #695
07/20/01 03:59 PM
07/20/01 03:59 PM
Joined: Jun 2001
Posts: 9,582
North-West Europe
Wouter Offline OP
Carpal Tunnel
Wouter  Offline OP
Carpal Tunnel

Joined: Jun 2001
Posts: 9,582
North-West Europe
John,
<br>
<br>>>If a mast limit is set it should take account of the existing boats, i.e. set it to the length of the longest mast. The Stealth has 8.4m mast
<br>
<br>Thank you, I will update the webpage with this info. I agree with you on your last comment. I can live with 9 meters max. For I actually doubt wether higher masts on 16 foot cats are practical if even optimal. I really don't think that there is enough hull length to prevent a higher masted F16HT from pitchpoling. So the limit of 9 m. sounds fine to me. Anybody got objections ?
<br>
<br>>> My comments on the weight carrying ability are that it seems to me that f16ht will end up with similar sail area to our Stealth R for which a crew weight of around 145kg is best. f16ht will be a foot wider that the Stealth so it should need less weight to keep it upright.
<br>
<br>Yes, but we'll hurt the light crews in their jib area when going upwind. Going downwind you don't need the width. But your right, the Stealth sailarea are quite close to a viable F16HT implementation. And yes, the Stealth will prefer lighter crews. The Taipan 4.9 will prefer the heavier cews with its higher mast and larger sail area and less weight. And this is good because than each boat takes care of a particular spectrum of the weight range. If the question is if the F16HT will be a boat for light crews ? I think not for the rule framework is designed around 150 kg's creweight with a 10 kg margin up and down. So the competitive range will be 140 kg's to 160 kg's or "guy with girlfriend" to "two guys", this seems to be a good medium range to me. And ofcourse it is WAY faster than any other 16 foot class and several of the 18 foot classes around. Not bad with on average 150 kg's on board.
<br>
<br>I did some mpre math on the Stealth now I know that the mast is 8,4 mtr.
<br>
<br>- This should alow the luff to increase to 8 mtr.
<br>- Mainsail can be kept at same area
<br>- jib goes to up (or down) to 4 sq.mtr with a luff of 5 mtr. or longer (down to genaker boom)
<br>- weight stays at 117 kg's
<br>
<br>This results in TR going from 106,83 to 104,73 and the need for a heavier crew or wider platform (from 2,29 to 2,38mtr.) Now still 1,73 points to go :
<br>
<br>This can be achieved by
<br>
<br>- Losing 12 kg's somehow (sailing with a crew of 138 kg's)
<br>
<br>- 0,3 sq. mtr extra mainsail with ewxtra luff length and losing 7 kg's somewhere (crew of 143 kg's, getting nearer to your 145 ideal weigth) and going to 2,43 width, all still very well within F16HT framework
<br>
<br>-Or the best of all. Go to jibsize of 4,25 (max under F16HT) with a luff length of 5 mtr. or more (going down to genaker pole), increase luff main to 8 mtr. without adding area, loose 9 kg's somewhere (5 kg on crew arriving at tyhe optimal 145 kg's and 4 kg's on boat) and boat width stays the same. Now you're right smack at TR 103,01 and everything is at 83 % (drag and sailpower) And Stealth is the most equal to F18 of all the boats. But with a better genaker luff length than F18 so it will smoke F18's on a regular basis. No big spending involved for we can keep the mast and 4 kg's weight saving on the boat should be possible with simple mean (rudderstocks ?).
<br>
<br>O BTW I used Texel measurement data and it gave Stealth at 117 kg's and main at 14,19 sq. mtr. is this true ?
<br>
<br>For the 83 % discussion go to :
<br>
<br>http://www.geocities.com/F16HTclass/F16HT_to_F18_equality.html
<br>
<br>Do you think that this can be done without upsetting the original Stealth boat balance ?
<br>
<br>Wouter.
<br>
<br>
<br><br><br>


Wouter Hijink
Formula 16 NED 243 (one-off; homebuild)
The Netherlands
Re: Q 3 : What do you want covered in the rules ? [Re: Wouter] #696
07/21/01 04:05 PM
07/21/01 04:05 PM
Joined: Jul 2001
Posts: 67
Netherlands
geert Offline
journeyman
geert  Offline
journeyman

Joined: Jul 2001
Posts: 67
Netherlands
Wouter,
<br>
<br>I'd like to see as little restrictions as possible, but still trying to avoid making the class too expensive.
<br>
<br>Beam: max. 2.5 mtr;
<br>Almost everywhere trailarable, and not a real limit.
<br>
<br>Carbon mast: allowed;
<br>For ease of righting, handling on the beach. About cost, I think if we set the minimum total weight not too low, anyone can still be competitive, as taipan's with aluminium mast's are already quite light. It just helps to get more different boats into the class. (also the ones who can't achieve the min. weight with an aluminium mast)
<br>
<br>Spi: fixed max sail area between 17 and 21 m^2 (21 is max. according texel rating rule)
<br>I'd like also see a fixed luff length, to be calculated but:
<br>Make it as long as possible, just avoid the extremes, I'm a bit afraid of "masthead" spi's (more prone to breakage?), or say that the attachment of the spi must be at least 0.5 mtr down the top of the mast.
<br>
<br>Pole length: Like Formula18/Isaf rating/Texel rating: may not be longer than the longest distance between the fixing point on mast or mastbeam and the theoretical uttermost end of the boat, + 80 cm
<br>
<br>
<br>Minimum weight (2-up): 105 or 110 kg (including spi)
<br>Although I like light boats, I think it's not reasonable to go lower than this; it would make all existing boats already obsolete.
<br>For example:
<br>
<br>The Taipan is about 105kg, add 6 kg for the spi (it won't be much less) and it's 111 kg.
<br>The Stealth: 109 kg + 6kg= 115 kg
<br>Bim16 110kg (measurement in Holland) + 6kg =116kg
<br>
<br>And these are already the lightest boats around.
<br>
<br>Maximum length: 5.03m (this just includes the stealth)
<br>
<br>Sail area:
<br>For what kind of calculating for the Jib; I'll leave it up to you, but if you want to calculate, I think it's better to take the (max) luff lengths for main and jib, and not set a max mast length.
<br>I also like the idea to take a "rated" sail area; this also limits the need for a very high aspect-ratio sail (and thus a very long mast)
<br>This formula's are the same in Isaf and Texel rating, and are public, so everyone can see what the effects are.
<br>
<br>Geert
<br><br><br>

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Welcome on the F16 HP ! forum Geert. [Re: geert] #697
07/21/01 05:46 PM
07/21/01 05:46 PM
Joined: Jun 2001
Posts: 9,582
North-West Europe
Wouter Offline OP
Carpal Tunnel
Wouter  Offline OP
Carpal Tunnel

Joined: Jun 2001
Posts: 9,582
North-West Europe
Geert,
<br>
<br>Welcome, this forum is working out isn't. The usage of this new media would justify the HT extension just a bit, don't you think. But than again the number of views and posts would also qualify it as High Performance ! =)
<br>
<br>Okay, you comments are noted in the poll. Let me react to a few points you've raised.
<br>
<br>>>I'd like to see as little restrictions as possible, but still trying to avoid making the class too expensive.
<br>
<br>I'm with you here all the way and I think that all of the 10+ group members are.
<br>
<br>>>Beam: max. 2.5 mtr;
<br>>>Almost everywhere trailarable, and not a real limit.
<br>
<br>Noted, and agree ; especially with the last bit. If it was needed than the Isotope, BIM, Stealth and Taipan would have been wider than 2,24 ; 2,28 ; 2,29 ; 2,34 mtr. Raising mastheight from old height to 9 mtr. would only need 12,5 % ; 0 %; 7,1 % ; 5,9% extra width respectively resulting in : 2,52 ; 2,28 ;2,45 ; 2,48 mtr. This when crew is left at the often low intended crew weight. F16HP will however often be sailied with heavier crews of 150 kg's and more and THEY don't need this extra width.
<br>
<br>
<br>>> Carbon mast: allowed;
<br>For ease of righting, handling on the beach. About cost, I think if we set the minimum total weight not too low, anyone can still be competitive, as taipan's with aluminium mast's are already quite light. It just helps to get more different boats into the class. (also the ones who can't achieve the min. weight with an aluminium mast)
<br>
<br>
<br>Indeed, The heavier ones can buy in by going carbon. Personally I'm quite attracted by the propect of better sail control and depowering in combination with less pitching. F16HP will give a fast but controllable and smooth ride.
<br>
<br>
<br>>>Spi: fixed max sail area between 17 and 21 m^2 (21 is max. according texel rating rule)
<br>I'd like also see a fixed luff length, to be calculated but:
<br>Make it as long as possible, just avoid the extremes, I'm a bit afraid of "masthead" spi's (more prone to breakage?), or say that the attachment of the spi must be at least 0.5 mtr down the top of the mast.
<br>
<br>
<br>I was pointed by I think John P. and Pieter Jan Dwarshuis to the fact that carbon mast could be easily made extra strong to take the extra genaker load. This would not help grandfather boats unless they get a carbon mast but it is masthead genakers are definately an option for the future. Personally I might rig my old P16 with a second hand spi and support my weakend old mast by two dyneema lines running from the sideshrouds pintles to the sailgroove at the hoist point. I'll be using a small diamter bungee cord to keep to line slack when putting on downhaul going upwind. This will almost completely cancel bending stresses and still not be in the way when trapezing etc. Isotope could do that too, the other grandfathered designs are well in the clear, I think.
<br>
<br>
<br>>>Pole length: Like Formula18/Isaf rating/Texel rating: may not be longer than the longest distance between the fixing point on mast or mastbeam and the theoretical uttermost end of the boat, + 80 cm
<br>
<br>
<br>Yep, agreed and so do the others, some want to go shorter and that is ofcourse allowed under this rule.
<br>
<br>
<br>>>Minimum weight (2-up): 105 or 110 kg (including spi)
<br>Although I like light boats, I think it's not reasonable to go lower than this; it would make all existing boats already obsolete.
<br>
<br>
<br>Ehh, not really for F16 HP takes Overall weight , including crew, into account. Having a heavier boat can be largely corrected by sailing with a lighter than 150 kg crew. It will not be perfect but than only Isotope is somewhat heavy. Both Phill and I think Boyer too and not to forget John P. have stated now and in the past that 16 ft. (timber) boats could reach 100 kg's safely. This will push for some light development in this direction though, I'll admit to that. I consider it a provision for the future. and Ofcourse the 83 % rule only works at exactly 99,25 kg's (say 100 kg) and not 110 kg.
<br>
<br>>>For example:
<br>The Taipan is about 105kg, add 6 kg for the spi (it won't be much less) and it's 111 kg.
<br>The Stealth: 109 kg + 6kg= 115 kg
<br>Bim16 110kg (measurement in Holland) + 6kg =116kg
<br>And these are already the lightest boats around.
<br>
<br>Well, your numbers are correct ofcourse BUT (sorry) we must allow a carbon mast on the Taipan 4.9 for example, ergo - 4 kg's (maurizio old forum 3 days ago). Than Phill has homemade full carbon rudderstocks, ergo another 1,0 kg's and rudders/boards ! again -4 kg's. Homemade Taipan carbon boom and genaker pole, - 2 kg, dyneema trapeze wires and pole wires (work great on my boat), - 2 kg and we're already at -13,0 kg's So a F16 HP taipan 4.9 of your 111 kg's - 13kg = 98 kg's. Ohh, ... ehh, now lets say I overestimated by 2 kg's ... and Hoppa 100 kg's (Teasing a bit, sorry =) )
<br>
<br>Hell, I know a homebuilder that weighted the base sheets of ply before buying and selected the lightest ones and won a 2.4 kg's that way !
<br>
<br>I don't know about how far the BIM can go or the Stealth because I know the Taipan much better, But if Petrucci builds A-cats at 75 kg's than he must be able to produce his Bim at the advertized weight of 95 kg's even though the 110 kg's found at Texel is without a doubt correct.
<br>
<br>My point is that 100 kg's is "achieveable by practical means" as John P. himself put it. (e-mail or post, I forgot).
<br>
<br>But you do have a point. Taipan is base at 102 (class rules) and can kept at that weight by leaving class complience by going carbon mast and boom when adding a gen. of 6 kg's
<br>
<br>Still I think that the transition to 100 kg's will take a few years and that is enough time for the class and grandfathered boats to slowly adjust to this weight.
<br>
<br>
<br>>>Maximum length: 5.03m (this just includes the stealth)
<br>
<br>Yes, I'm strongly apposed to that, Doing this will mean that all new boats will be build to 5,029 mtr. Thus giving the other grandfathered an extra hit lengthwise and genakerslot wise and the already were at 4,95 mtr. I must remain as neutral as possible in these F16HP discussions but I really want to keep the max = 5 mtr + margin of building error and dispensate the Stealth design for its non complience to the length rule under the condition that any newly designed stealth hull is 5 mtr or less.
<br>
<br>>> Sail area:
<br>For what kind of calculating for the Jib; I'll leave it up to you, but if you want to calculate, I think it's better to take the (max) luff lengths for main and jib, and not set a max mast length.
<br>I also like the idea to take a "rated" sail area; this also limits the need for a very high aspect-ratio sail (and thus a very long mast)
<br>This formula's are the same in Isaf and Texel rating, and are public, so everyone can see what the effects are.
<br>
<br>Yes, I'm investigating ISAF for this may rate daggerboards and genaker size.
<br>
<br>Greetings,
<br>
<br>Wouter
<br>
<br>Geert
<br>
<br><br><br>


Wouter Hijink
Formula 16 NED 243 (one-off; homebuild)
The Netherlands
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