Rules

Making the rounds of the innerwebs this morning, it looks like there are more and more foils and T-rudders. Maybe it's time...

T-foils are allowed as long as max width is not exceeded.
Not much you can do in the main foils dept. though.

I dont know what the growth in the class looks like? I would think we want to wait a bit longer before going that route.

I agree that it looks like foils might be a viable options in a not to distant future. Still remains to be seen if they will be faster around the course Let the C-class guys go through a few more iterations on the topic..

Well, since dagger boards aren't required, why can't you use most any type of foil, as long as it doesn't have to fit through a dagger board trunk?

I dont understand the question.. Are you thinking outside the rules or inside?

Outside the rules anything goes.
Inside the rules the "practical" aspect is quite important for most. Flipping the boat on the side to clean off weeds and plastic bags is quite slow

I am leaning back and watching the developments. It is my opinion that it is currently to early for the F16 class to consider allowing foils. Let the pure development classes experiment a bit first. Or by all means, go off experimenting with an F16 platform and measure the performance up against a standard platform. I will totally support that! We should allow experimental platforms to race with the class but without scoring the experimentals.

Inside the rules.

I like the idea of experitmental boats.

IIRC, the rules don't allow appendages but don't require dagger boards. So, can you attach some sort of foil to the cross bar, or add a structure to support gybing boards?

Gybing boards would be OK as long as they dont tilt inwards more than 6deg.

A horizontal foil attached to the cross bar would probably be against the "spirit of the rules" or something like that. From what I remember the rules were crafted to not allow full foiling by purpose.

Foiling seems to be the cause du jour. We'll see how it plays out I guess.

http://www.youtube.com/watch?v=taJYT4eAiWE&feature=youtu.be

http://www.youtube.com/watch?feature=player_embedded&v=lgjvK_2JZmo

He has a nice building blog as well.

http://raphael-censier.jimdo.com/catamaran-classe-a/6-photos-construction/

Cool to se homebuilt boats! Hope more people take up the interest.

The big question, is foiling faster, remains to be seen

I think foiling is clearly faster, consider Sailrocket, Hydropter. Control seems to be an issue.

I was talking to an A class builder and he maintains their boats are now going to weather with only about 1/3 of the lee hull in the water. Imo, that has to be both higher and faster.

Btw, I exchanged posts with Wayne Marlow yesterday and he has put an A class rig on his F16. Any idea how that might work?

An A class rig on a uni F16 should be very nice. Two up would perhaps be more load than the mast was designed for. We discussed this some time ago on this forum I believe as part of the "uni vs two-up" performance thread.

Consider "Rocker" C-class who was not faster than the other C-Class boats http://www.stevekilling.com/SteveKilling_CSYS2009.pdf


It still remains to be seen where development will go. Interesting time to watch and even perhaps play a bit.

As I watched the last 30 seconds of that A cat video, it showed me exactly why I don't want to foil! Up down, Up down, you are basically riding a teeter-totter, and he was in flat, smooth water. Now, imagine trying to ride that hobby horse in some waves!

The previous video, with the Phantom, also shot while sailing on flat water, but obviously it has some type of foil on the rudders that is helping both to lift and stabilize the boat. I think that is the biggest problem to overcome, trying to keep the boat stable, up on the foils, while also going up and down over waves.

The C class Cats tried it a long time ago, and finally abandonded it, I thought because it was only faster when going downwind, not upwind?

So, if we are going to go down the Foiling road, we may need to change our race course layout to more reaching/downwind.

That's an excellent docutment Rolf, thanks for posting the link! Pete, skip on down and read all of page 15.

Here's one small part I pulled from there:

She proved very stable in both pitch and roll axes,
leading her crews to have confidence in their ability to
control her. In more breeze, at higher speeds, it proved
important to prevent her from riding too high, as the rudder
elevators, which were not as deep as the daggerboard
wings, could surface and ventilate, whereupon they would
lose lift and settle into the water. This pitched the bows up,
and as the boat continued forward she would then fly the
main foils out of the water, ventilate those, and crash (with
some measure of grace) back to the water surface. It was at
those times we were grateful to have used full-length hulls.
Importantly, we never capsized or pitchpoled the boat.
Figure 24

So what's your take on canted boards?

Foiling will kill every class, and everyone who's thought about it. Just look at the Moth.

Karl, was that sarcasm?

I thought the Moth class was actually getting more people joining, now that they foil.

Heck, I'm even considering it! Looks like fun!

http://www.youtube.com/watch?v=1SN1gSkqvy0

Although...Richard Branson makes Kite Surfing...with crew...look like MORE fun!

http://www.youtube.com/watch?v=kQ4GrxFgAB4

Yeah, lots of sarcasm.
If a no limits board rule came up for vote in the F16 class, I'd vote yes.

Dude, just quit fighting it and get an A-cat.

Who, me?

I told you, I can't afford it, or I'd have one already!

Too damn many kids, and horses!

swap that F16 of yours for that yellow Marstrom Acat in GA ($9,000 +/-) It's made for old-dudes like us

Where's that listed?

The women have horses for toys, and the moneymaker can not have expensive toys? Well.. I am divorced.

After the feed bills, board bills and Vet bills, there's no money left for food, let alone toys! I'm lucky if I can get a sixpack of Sierra Nevada Torpedos on sale some days.

I'm going out to ride my bike, if I'm lucky I'll be run over by a truck, I just hope it's quick.

Aim for the big ones.. Or start building an A-cat, that should free up your budget double quick

Hope you don't mind a has been chiming in, but I couldn't help but point out to Greg Goodall recently that he was one of the ones that wanted the rules tightened up for F16 to stop foiling centreboards (original rules had nothing to stop them) and a foiling centreboard cat was what stopped his drive for Olympic selection of the Viper. Just a bit of irony in that.

I have had a play on a foiling Moth and it is awesome, getting the right sort of foils on a cat has to be the answer, not like the A's which are trying to work within their rules.

Reading back through this Thrice might have a point. I feel in light of whats going on in the catamaran world at the moment, relaxing the centreboard rules might be a good idea. Its still going to take a while for any interested party to get the motivation to get it right so i dont think its going to make the rest of the fleet obsolete over night.

Over the past couple of years the box seems to be getting tighter and tighter. Instead of putting more rules in i reckon it would be a good idea for the future of the F16 to see a few outdated rules removed or relaxed a bit. Or better still i feel we should be going back to the original rule set before ISAF became involved.

I see now there is a push at the moment to tighten the sail rules even more. It means all of the sails start looking the same and keeps the construction stuck firmly in the stone age. New construction techniques we were using nearly a decade ago are now not class legal. Seems there is a bit of a push from i dont know who to try and make every boat in the world close to one-design. This makes absolutely no sense IMO as most classes in the cat world that are doing well are Box rule or at very least have multiple builders.

Hans resigned because one the French officials was trying to change rules unilaterally, iirc.

Do we have an international class president at the moment?

We have to decide what we want the class to be about.

Should it be a "Development Class" like the A cats?

Or should it be about keeping the rules tight, so the boats are more equal, putting more emphasis on the skipper and crew to win races, vs. some new dagger board, sail or what have you.

Development costs money, and takes time.

The two things I'm always short of are time and money.

If we go the development route, curved boards, foiling, etc. I'll be out, might go to a Hobie 16 or a Corsair, something where I don't have to spend additional time and money on every new idea that comes along. If I wanted to do that, I'd be on an A Cat.

I agree Timbo. The centre board thing is just an example, but its something to think about, and sails don't cost that much. I'm in a situation now were sails I built 4 and 2 years ago and were fine then, are now not class legal. I don't remember voting on that. Did any of you guys?

I came from the Hobie 16 so I can appreciate the value of one design. However the f16 box rules have been tightened significantly while both you and I have been in the class and we have had no say about it. It's not right IMO.

Not sure about class president, the french seem to be acting on their own from what I can work out.

When you start talking about curved boards and foiling then you get the possibility of some serious expense. Most of the other items that are being proposed are self governing. For example, the head size on the sails. If you have a pin head sail and move to a square top it has proven faster over most conditions. The A class has no restrictions on mast height, head size etc. They experimented with heads that got huge and found there was a definite limit. For a very short time you found a few teams running many different configurations. Go to an A class event now and all the masts are virtually the same height and the heads on the sails fall into a very narrow range of widths. There is an attraction to some to be able to change small things and we all learn as a result.

As far as your sails go Aido, who told you they were illegal? There are only a few restrictions on what you can do and these have not changed since the first version of the rules in 04 as far as I know and definitely, in 10 when the Isaf version was written there are no changes that can be made to rules for a period of 5 years. There never have been any material restrictions in the F16 class.

I heard rumor that this was the reason the Chairman resigned the class, because of things being done without approval

If things are being done, without approval....

why are they being allowed to race as F16's? Do rules mean nothing?

I think I'll skip the offset mark next time, see how that works out, I know it'll be faster!

There is quite an in depth discussion of curved boards on SA, with some knowledgable contributors.

My take away is that curved boards are not inherently superior but they are more suited to some applications. It does seem the A class is finding curved boards and rudder winglets are a performance enhancer. Krantz made an interesting post describing how he souped up an older boat.

Because we've all become to "nice" about not protesting or calling someone out .... if we don't self police ourselves then the rules really don't matter.

I think too many of us (myself included) that are older don't really want to protest and find ourselves in "the room" because it interferes with our social libations after the racing. With the attraction of the youth sailors, I think we owe it to them to mind the rules or 2 things happen that aren't good for our sport

1) they learn that you don't have to obey the rules
2) they get frustrated that everyone is not minding the rules and they stop participating

I decided (after sailing with Ding ) that I'm calling you out if you foul me.

Case in point, at recent regatta a boat (F16) fouled me (I had witnesses). I yelled "foul", give me turns, everything .... BUT ... PROTEST. I was going to take them to "the room" but several people said I'd lose because I didn't say the magic word "PROTEST".

Because of this, Sophie (a youth sailor) missed winning the regatta.

So minding the rules matter .... and it's safer for our sport ... ask Seth and Stefan!

THAT'S why we need these discussions.

So what's more important to you Timbo? Racing to win, racing to improve your individual ability, or sailing as a social event?

I think the answer would dictate how you spend the limited time/money you have at your disposal.

Racing has certainly improved my boat-handling ability, as well as my competency in higher wind/sea conditions which could translate quite well into less high-performance craft.

Since I'm too fat (180 lbs and falling) for you twerps on tiny boats, I have resigned myself to adopting more of a cruising lifestyle in the hopes of picking up a F-24 which would be about as "dual purpose" (moderately fast, trailerable, single-handable, and weekend cruise-able) as I could hope to afford.

That hurts my heart a little bit Terry, oh who am I kidding... I couldn't even keep a straight face typing that. That's right, if one of you b!tches steps out of line we will be spending some quality time in the room together.

When I first got into racing, at 19, it was to improve my sailing skills. Later, in my mid 20's, it was for the adrenaline rush of tight competition. Now in my 50's, I only do it for the social event afterwards, if/when I have the time and money to show up.

And I'm 185 on a light day, in the spring, after a 20 mile bike ride, but well over 190 during NFL season (beer, pizza induced) so you are lighter than me and a perfect weight for Uni or with one of the kiddes! BUT the two of us together, not even on an F18. Too bad nobody can afford to race an Inter 20 anymore!

Any of you Boston Boys see that Bruins game last night?

I believe the rules allow a board to be canted up to 6 degrees. Anyone know why? Is an increase called for? Would it do any good?

They aren't illegal cause they were made before they changed the rules.

The way i read it is the "one cloth throughout the body of the sail" stuff excluded a lot of construction techniques. I'd like to see you argue that a 3di sail was the same cloth throughout. Anyway guess ill just have to use the rules as they are, as its too late to complain now. Just dont want that sort of thing to happen regularly.

I wonder how much lift you could get out of 6 degrees of cant on your centre boards?

The rules now state that sails have to be built out of just one cloth throughout the body?

When trying to look up the rules, this is what I find on formula16.net




Choosing to ignore the warning, I go to the ISAF website and find this as the current rules (2012 rules): http://www.sailing.org/tools/documents/F162012CR220612-[12620].pdf

I find nothing there about sail materials under section C.10 - Sails.
Under section G.3.4.b I do indeed find this regulation: The body of the sail shall consist of the same woven and/or laminated ply throughout

Does this mean that new string sails or not allowed anymore? Any changes to previous rules would be marked in blue or red. This text is not marked so it should be a relatively old change (2011 or 2010). Why would string sails not be allowed? Cost?

Further I have to ask myself where the current rules are to be found when considering the text on the class website.




I suppose you would get 6deg + the angle you get from flying a hull and then solve for lift generated at different heel angles and different attack angles on the daggerboard after compensating for increased hull drag.

About 17kg

So how does that translate into useful performance?

Does anyone know why 6 degrees was decided upon as a rule?

Aido,
There has never been any restriction on materials for build or sails in the F16 rules. If there is somewhere now, it was not approved by the class.

It was done to allow for some development. This allowed for some experimentation but limited the range to a point where it would be unlikely to be any significant disruption to the class stability to have the feature or not.

The 6 degree point also provides a range to avoid nit picking various boats at the time of measure. What are not addressed in most other class rules on this subject are the various tolerances involved in a system. It sounds all nice to say things will be inline or vertical. You have builder tolerances, which if you measure some brands /models can vary quite a bit.
Look at the F18 rules, the boards must be inline with the CL of the hull. The front beam must be straight, but can have the dolphin striker tensioned to provide a prebend. If you have straight hulls and inline boards but tension the striker to full range of the rules, you now have something around a 2 degree inward cant on your boards. You can have more if you play with the trunk stops and who measures this when doing a cert on a boat?

I have now tried canted boards in my "almost" F16 for two seasons and are quite convinced they are worth looking at. The A class only went to curved boards to circumvent their rule dictating that the top of the board should not go outside the hull when in the up position, we don't have that problem and are probably able to achieve the same with the straight board. One only has to look at the Nacra F16 to see a manufacturers take.

We are missing a trick in not allowing A Class rigs for the single handers, very refined with a long history of development, they are readily available and seem to be superior to the rigs designed for dual handers we are left with using. Certainly I wouldn't go back to my old rig even though it is 1 1/2 metres smaller.

http://carbonicboats.blogspot.com.au/2013/06/alphabet-soup.html

If this is correct, monkeying around with foils could be a cheap way to increase performance rather than buying a new boat.

Pete see A-Cat development for this. As lifting foils were added to the platforms, changes to the hull shape were done in the transom. If you went full flying you could avoid this but that isn't the intent of the F16 class rules as I see them.

The average sailor is going to get more out of regular sailing and practice than monkeying around with foils, at least not building foils. I decided against it as my existing hot box fits my 66" long boards and that is it.

PGP,

You wnat to buy performance, then you should get into something with a motor.

Long foils, curved foils canted etc all have the POTENTIAL to add a small bit of performance in some given and usually narrow range of conditions.

Long boards now need to be constantly adjusted, curved foils require quite a bit more crew athletisism and skill etc. Improperly tuned or used features are slower. These things just make the good sailors maybe a bit better in some conditions, and the sailors who now have more than they can do to run their simple boat anywhere near optimum are even further behind.

Wayne,

We have Falcon's around with canted boards and we have Falcon's with straight boards. I have sailed both and have not seen a performance difference when looking at the results.
So I don't think the difference is huge.

Gill

Agree with there being little difference at this time, but !

What I do find with my boat which is probably quite low volume compared with the later generation boats is that at higher speeds the inclined foils do generate some lift, one only has to move my butt foward or back 100mm ( altering the AOA )to see the difference of how the foward part of the hull is higher in the water.

What I think also happens is that this negates the need to trap out with the spinny up, the boat if heated up and the speed increased to a point where the lee hull is high in the water, will go downwind just as well with me either sitting in or trapping. I'm not sure why but I think the extra loading on the lee hull from trapping, causes the lee hull to submerge more and thus drag over comes the advantage.

With the much fatter latter generation hulls I think there is enough volume ( width ) to create a form of "planing" which in effect is already making the hull a foil. Those wider hulls trying the inclined board are very much first generation ( the Nacra F16 is starting to move things on with their long high aspect boards ) and due to the ventilation issues we are seeing ( just like the early moth tube vids where they had to incline the board a few degrees ) plus lack of adjustment to best set up a boat,are probably not good examples to be using for justification of or not of , foils.

What if we can generate planning and lift and get it useable. I think this is where the A Class is heading, I personally don't feel they have got there yet but with the new S boards such as the Carbonic boats, they stand some chance.

But we on the other hand have some advantages that the A's do not. We have a rig which is much more powerful than the A's to utilse foils better. We have no max or min overall board rules so we can move the foils outwards or even have the top of the withdrawn boards wider than our max width. We have an extra pair of hands to operate the foils better ( see the Phantom 2 http://www.youtube.com/watch?v=5doBIv3TVbA&feature=player_embedded to see what can be achieved ), we have a jib which balance the boat better upwind, we have a very large spinnny for downwind, we are wider at 2.5m and I could think of other reasons as well.

Sooner or later someone will pop us the myth of expense of the S Boards or C boards. Virtually all board moulds are now CNC machine cut. Machines do not care whether it is a straight run or constantly arced, it just another point in time that the machine head must reach. So yes the mould may be marginally more expensive but only marginally. Yes there will be more carbon to strengthen the board due to it now effectively lifting and carrying weight, but that extra material cost in the whole scheme of things will be only a small part of the total cost. At the moment the A class boards are falling in cost as more and more manufacturers are coming into the market.

So do not diss foils, they are the future, perhaps not fully foiling but certainly foil assist in our case. Perhaps we as an semi experimental class should be allowing any board shape or size, the privateers will experiment and the manufacturers will lag behind as usual but we will modernise as we go along, making the class much more appealing to all.

Basically I agree. I think upgrading an existing boat protects the owner's investment.

Yeah, thats the way i see it too. I'm thinking because of that, the new restrictions wouldn't be valid????

Back to the center boards. If you twist the boards in the case that would give you even more lift with straight canted ones wouldn't it?

17 kgs is crap need about 260 kgs at least.

Adding my two cents. Sailing catamarans for 30yrs, current owner of an f16. Last weekend I got an opportunity to sail a F20c in 12-18 knots of breeze. The boat did jump out of the water on us a few times up wind. A fun experience but not a fast experience.
Downwind, single trap conditions, the curved boards created a special ride. The boat was not foiled up out of the water, but from the dagger board well to the bow she was clear of the water. The speed was in the 21 knot range. Steering got super sensitive because it felt like any turn of the tiller was not turning the hulls, but rather pivoting the boat on the curved board.
Overall I really enjoyed the curved board experience.
The phantom project might prove curved boards are outdated shortly?

Like Tim, I am short on money and time. But if my F16 manufacturer came out with a curved board package(kit) that was tested for the F16, granted non class legal, and the price was not ridiculous, I would go a head and make the change.

I am finding the biggest limitation with the F16 is the length. I solo the boat mainly, and really feel comfortable in pretty high wind conditions. It is the sea state, wave conditions that will cause me to back off sooner then I would like too. I wounder if the curved foils would improve the F16 ability to handle rougher wave conditions?

with straight (canted) boards the vertical lift will always be directly proportional to lateral lift. The total lateral lift (across all boards, hulls and rudders approximately equals (total righting moment) / (0.45 x Mast height). On a modern cat approx 70% of this lift can be attributed to the leeward daggerboard. Then it comes down to basic trigonometry and vertical lift = lateral lift x tan(angle of board + angle of heel).

260kg is more vertical lift than the required lateral lift so a straight board would have to be canted more than 45 degrees.

F20c sounds like a sweet ride need to get on one

T-foils on the rudders. A lot less work than curved foils. i think they would make a tremendous difference in the short lumpy stuff especially on the finer bowed boats like the Blade.

Anything new? Was there a class meeting at Racine?

There was and I think the consensus was to leave the rules alone.

Were the minutes published anywhere?