Agreed. The end of the process is to add all positive features we can to the best concept, regardless their origin, but sticking to the chosen concept.




Yes, but note that I am spanning the original age range with two up.

As Wouter wrote, a cat that is optimal for 12+ year old kids is also a very good choice for a couple of kids under 12. This adds a very important marketing feature to the class, for then it will be a strong replacement/competition for both the Optimist and the Laser - while interfering little with the original goals.

Also, note that this is a tough feature to replicate in a monohull class: a Laser can be sailed by two small kids, but it is hard for them to keep the boat upright when tacking and jibing (have you noticed the high beam of the Optimist? It's no coincidence).

The cat's high initial stability makes life a lot easier for the small ones. I think we must use this advantage in our favour as much as possible, if anything because we can't get read of the inherent disadvantage: the tendency to go to irons when tacking.

The trapeze is a source of interference with the original goals. If we accept that it is indeed advantageous for the class to target this segment (startup boat for ages 7 to 12), we'll have to analyse this feature carefully, for it leverages the advantage that kids over 12 have against two smaller ones.




Good point.

The problem with a formula is that parents start competing to see who spends more on the kid's boat. This forced the Optimist to become a strict one design. Even with the narrowest possible rules, parents still find ways to spend a lot on their kids to give them an edge (buying high tech lines, gore-tex clothes, multiple foils, sails and hulls, etc.).

This is another interference caused by the increased age span. Younger kids' parents require strict one design rules, while older kids (and their parents) can live with a formula - and possibly have more fun with it.

As a consquence, first we must discuss if the "two up under 12 startup" use is a desirable feature for the class or not. Needless to say, I favour this feature. Here's why:

Even with Internet, I don't see a group of teenagers managing a Formula class. In most of the cases it will be their parents doing the work.

If parents must be involved, why not catch them earlier, at the same age kids start sailing Optimists? It is easier and it makes more sense to me.

If the class is sailable during a wider age span, the class organization becomes stronger. Parents managing the Optimist class usually help for 6 to 10 years, maximum. If the same boat was good for a couple more years (as would be our case), they would help for 8 to 12 years. We all know how difficult it is to find people to help, so this is a great benefit for the class.

I'd like to hear what others think before continuing, because I may be trying to convince the converted...

Kids I've spoken to range from 7 to 14, but most would be 10 and up
RG

Right now based on what parents and kids are telling me, I'd say that the only person who wants the round bilge design is me <img src="http://www.catsailor.com/forums/images/graemlins/smile.gif" alt="" />
So, if I follow exactly what those interested want (not counting those here), its a hard chine design, with boards, that can fit an age range from 7-8 thru 16+, that can accept either rig, although the majority appear to want a stayed rig.
To be fair, most of the kids Ive spoken to come from sailing families, most own or have sailed opti's (and are really bored with it) and one or more of the parents sail multihulls.
Just from my personal perspective, I see the ability to swap from one rig type to another as a design plus that gives the designs more utility over the age range and beyond, perhaps the easiest way to deal with it is just cap it around some age limit?
RG

Im looking at exactly the same age spread also hoping that some will go on to crew for adults or go to F14 from there on. I think I'll be able to get novice adults (read parents) out on these boats. My preference is multi design so that if a parent wants to get excited in the sport encourage them, I hope we can come up with a simple handicap system to encourage young enthusiastic sailors to strive for their maximum potential and nurture the ones just doing it for the fun. I can see two 7 year olds doing a roll tack and cackling the whole time.
regards

Just got a call from a father who sails an A-Class who has a 7 year old who wants a boat and his suggestion was use a boomless pocket luff rig with a curved (decreasing radius) traveller (so it cambers up automatically as you travel down) and this way kids can't bang themselves on the head with the boom if they aren't paying attention or it gybes on them when they aren't expecting it (which will happen). The cost difference for getting a slightly longer bent traveller is more than offset by not having to purchase the boom and it will speed up the rig/derig time.
cheers
RG

Had forgotten to give you people some floatation numbers, with a 65 kg platform and a 45 kg kid, on both hulls it will float approx 29mm below the tip of the bow, on one hull its exactly at the nose. With a 75 kg crew, it will sit down a further 36mm when on 1 hull. And for those extreme conditions where all the neighborhood kids pile on the boat and its sunk to halfway up the transom (110mm above DWL) it will support 221 kg on one hull .... thats almost 5 45 kg kids or 10 of them when it's on both hulls. Not sure the beams or the rig will standup to this punishment, so just don't tell the kids it can do it <img src="http://www.catsailor.com/forums/images/graemlins/smile.gif" alt="" />
Cheers
RG

I guess the design could be made to accept either rig, obviously at the cost of adding specific structural reinforcements.
Can you estimate the weight increase, if significant?

The two configurations are:

- "School" configuration - free standing mast / two kids under 12 / hiking straps.

- "Competition" configuration - stayed mast / one kid over 12 / trapeze.

The question remains about the type of class rules: one design, formula or split? (split meaning one design for the "school" version and formula for the "competition" version).

If the class rules are made different for each configuration, two classes will be born - and in the end one will be a strict one design and the other a Mini A.
I guess this alternative can be excluded because (as I see it) we want to converge to one optimal class rule and/or design.

If one rule covers both configurations, it's one class with two purposes, much like the 420 (a one design class with two configurations: "club" and "competition").

I prefer the club and competition versions and to that end I have started to modify the way it's set up so you can run either configuration on the same platform, with the same mast and with a hybrid sail so you can use the same sail for both configurations as a "cheap" option for growth. Need to change things a bit, but should have some pics showing how its done by late tomorrow or the next day.
Cheers
RG

Luiz,
think I can get the weight penalty for the above to about 0.5kg or less, will know more after I have calculated the changes. Will let you know soon.
Cheers
RG

If you want the excel sheet uploaded to a website then send it to me and I will place it on :

http://www.xs4all.nl/~whijink/F12/


Wouter

Another argument I found against trapeze is that is does add cost beyond its direct advantages. Mostly because you have to buy a kids harness which he or she will grow out of very quickly necessitating maybe a new harness 3 years down the line ? These kids do grow at a pretty impressive rate. In the end it is just another thing to buy when a kid starts out sailing these and it all adds up in my opinion.

I figured that it was better to just add a little more width to the platform and hike to get to the same overall performance.

Wouter

RG,

I serious doubt that the cost of a curved traveller is less then a those of a boom. Afterall the later is nothing more then a piece of plain round alu tubing.

The solution to this parent whishes is probably better served by a wishbone boom see picture on a landyacht.




Basically it is a windsurfer boom that is fitted higher up the mast. The wishbone boom can angle downwards towards the clew corner arriving at exactly the same mainsail surface area as a normal boom. This wasn't done on the landyacht as a person is sitting up straight beneath the sail and his head will otherwise be in the way.

The attachment of the wishbone boom is extremely simple. It is just a loop of some high strength line that goes around the mast. A single line at the rear (hook ?) sets the draft and the mainsheet is directly hooked to the sail and not to the boom itself.

It is not even hard to modify a boomed sail to take a wishbone boom. Just have to cut the sleeve open and reinforce it. The rest can remain unaltered.

An additional advantage of the wishbone boom is that the need for a kicking strap or ram vang has been negated. The luff of the sail itself will act as a kicking strap and prevent the boom from rising up to far when the mainsheet is released.


For enthousiasts and designer looking to use old windsurf masts. I have less then encouraging news. I've been trying such masts on this landyacht and found that nearly all plain windsurfer masts are far too flexible and will "pump" in unstable winds which is not a nice behaviour for a landyacht or sailboat. Basically these masts will have to be reinforced to make the stiffer. Inserting a second mast of same taper is one of the ways to achieve this. This does add weight and you will have to open the mast to take the local boom location reinforcing out.

Wouter

My comments on your spreadsheet.

I would like to add a few comments on the "OD F12" in your spreadsheet.

Trapeze/Hiking :

The given 7.00 sq. mtr rig on a 6.00 mtr mast (that is what we all agree upon right ?) will only be able to produce so much heeling moment. The OD F12 will resist this by hiking on a wide platform, while the trapezed F12 will resist this on a trapping on a more narrow platform. You don't win much by trapping on a wide platform, mostly because the rig will then not have you trapping unless the winds are really strong. That was the idea behind the hiking OD F12, just add a little extra beam width to compensate.

From memory I think that my design achieved 2-up trapping F18 equality at 2 mtr wide for a 53 kg crew.


Speed :

From what I know and have seen on the water, many will be surprised about how small the performance difference between a multichined and a round bilge hull will be when all else is the same. We are not talking more then say 3 minutes per hour racing at max here, which is pretty negligiable.


Stability/pitching :

My F12 design was to be fitted with T-foil rudders, especially the deep V-ed keel version. In my opinion this is the most simple and inexpensive way to get excellent pitching behaviour. As per what Darryll did with his F14's, the T-foil rudders use plain kickup rudderstocks. On the F12 the rudders and T-foils will be too small to develop enough force to break off the sterns or stocks anyway. On the Alfa Omega F14 did was already the case. As such the little T-foils are just permanently screwed to the bottom of the rudders. Plain and simple, easily replaced when damaged.

I think these points will increase the points assigned to the "OD F12" a little

Wouter

I added the requested modifications to the spreadsheet. The file should be in your hotmail direction by now. See the "2" sheet. A picture follows attached, so nobody has to wait for the upload.



I'd like to comment (and read other comments) on the features of Phil's Blade 12, as posted in the Open forum:

- The mainsheet and rudder crossbbar setups are great, ideal for kids. This setup should be mandatory.

The dolphin striker receptacle for the freestanding mast is neat, but I like the struts better because the dolphin striker can hit a child's head when righting the boat, while the struts help coming back on board - besides other advantages we already wrote about.

I hate to say it but this part of the design is also 4 years old now :

See below the artist impression I made for Phill Brander in late winter 2003.




Notice the mainsheet setup ?

Phill is going to be really pissed at me, but I'm going to say it anyway. The time has come to actually produce a design and not more artistic impressions. It is great to see Phill has found a new person with much more advanced skills to make these flashy pictures but in the end of the day these are nothing more then a bunch of glowing pixles on a computer screen. It is time to produce detailed cost and weight tallies. Work out the materials used and the individual dimensions of the parts. Many will find that a few more snags are encountered here and will need to be overcome.

I really love how Phills Blade 12 looks and indeed we discussed its OD status as far back as 2003/2004. I was surprising to see Phill come out for a more open class rules based F12 class on this forum knowing he was fully working towards his own OD Blade 12 setup. This is confirmed by his own admission on the main forum. His pod like setup for the unstayed rig will most definately work. The mast design I have presented in this post can be used for his setup without any modification. It appears his mainsail is basically the same area the same as the sail depicted in the photographs (5.5 sq. mtr).

But the flashy picture do mislead people a little bit. The Hulls for example. These "appear" to be scaled down Blade F16 hulls with a rounded keel. Not even Phill himself believes that these can be homebuild without a serious building effort, meaning multi panel construction that is steamed into a rounded shape. Basically these hulls will not be much different in building requirement then the Blade F16 hulls. A multichine hull or even a deep V-ed hull design are much more likely to be chosen eventually and as such it will be much better to show these in the CAD drawings, like RG does. At least then we all see what we are getting into.

Either that or Phill will do best to clarify how exactly these compounded hulls can be made with very simple tooling and small time investment.






It is interesing to note that the OD class rules that I have written up earlier actually do NOT rule out the pod setup that Phill prefers. Basically, in that OD class both the rod and pod setups can be used legally. I would like to stress once more that the OD class rules are not SMOD and that apart from limiting a few design features in a very strickt sense, like the hullshape and the requirement of an unstayed mast, other aspects are left completely open to personal preference. I don't see any reason to not allow design freedom in these ways.


I do really like Phill Blade 12 and I always have, even though I have differed in opinion on some design aspects. But when made well the Blade 12 will be a good design.

Wouter

Luiz,

Your stuff is now uploaded to the website :

http://www.xs4all.nl/~whijink/F12/

direct link is :

http://www.xs4all.nl/~whijink/F12/Comparison_Between_Design_Trends_draft.xls


Wouter

Wouter,

I've posted some pics of a craft that I will build because I think it will work at attracting kids.
My suggestion is that everyone else build what they think is right to capture the imagination of the young.
Hopefully someone will get it right and kids will be drawn to the sport.

BTW:-
I will be posting building pics on my website.
Then people can judge for themselves regarding your claim that I am misleading people.
A picture is worth a thousand words.

Regards,
Phill

I like all your designs, ang I would like to vbuild them all.
But are we not about to forget one thing? The kids were supposed to build their cats? The designes and solutions start to be far to complicated for kids say around 12 to build, even a chained hull is not so straight forward to set up.
I am not an expert in any way in boatbuilding, but I have been working with kids on both wood and metal and my experience is that it has to go fast and change all the time...

Gato,
I have built many boats many different ways.
Provided you have well thought out building instructions the deep V should be the quickest to build.
It should keep the kids interested.

When I post my building pics you will see how much simpler the Blade 12 is to build when compared
to the method used on the 16. And while it will have a lower draft and carry more weight than the V
it would still take a little bit longer to build.

I wish you the best of good fortune and will follow your work in getting these kids involved with great interest.
Good luck.

Regards,
Phill

No war has ever been won when allies are also engaged in fighting among themselves. I think this gave rise to the saying "Divide and Conquer".

Basically I disagree with the notion that we should all do our own thing and have the market place sort us out. The end result will most likely be that we all fail and waste alot of effort and resources in the proces. More importantly even, we will fail to effectively compete agains designs like the Open Bic and 29-er.

I also think "hoping" is an generally bad strategy.

So the question becomes, are you "in" with the F12 project or are you more interested in doing your own SMOD thing ?

Wouter