Carnac 2012 - results

This one's a little easier to read - http://www.yccarnac.com/uploads/htm... eurocat%202012/eurocat_interseries_g.htm

Gill - just out of interest, do you what the line honours results were among the F16s competing? Dan

For the buoy racing line honours are more difficult to tell. For some races it didn't matter, but for our 333 youth team, on one race they lost 5 places because of the racing.

For the raid it is a different story.
First Falcon finished just below 2 hours (less than a minute behind Bundy) and clearly 3rd F16, beating the Nacra's and most of the Vipers were some very talented sailors where placed on. Our Swiss team finished in front of Chris&Georgina and the Cirrus Q but ended up 19th, the Cirrus 10th... So here the rating has a bigger effect.

Overall very good performance of all the Falcons there, showing weekend racers can mix it up with the pro's.

Buoy racing results: http://www.yccarnac.com/uploads/htm... 2012/eurocat_interseries_g_definitif.htm

Long distance results: http://www.yccarnac.com/uploads/html%20resultat%20regate%20de%20freg/raid_eurocat_2012_g.htm#GRP_2

Regards,
Gill

Any pics of the Cirrus Q?

+1

Some great action pictures available now: http://www.facebook.com/media/set/?set=a.10150808071409393.436568.271892154392&type=3

Some Cirrus Q pics can be found here: https://picasaweb.google.com/116154434120608898008/Eurocat2012?feat=flashalbum#

Those are some seriously long daggers on the Q. Photo #359.

Pic

First time I've seen both spin blocks on the front beam. Looks like the blocks closest to the chute's clew can slide independently outboard to

open

up the chute.

Pic

Interesting comparative view of the

R

&

Q

.

Pic

You mean like this ?

Full high res version at this link

would having the spin block on the beam like that shorten the foot of the spinnaker?

No most spinny's have now been limited to min foot length by the definition of what is a spinnaker and what is a reaching sail( see SCHRS for definition )ie we are all at min foot length already due to the apparant wind requiring very flat sails. By choice I would be even flatter if the handicap system would allow it.

On the Cirrus I would suspect they have moved the front beam back as per A Class design and kept the max 3.5m spinny pole and thus the blocks have to go as far foward as possible.

This is excactly what I found on my boat which was derived from an A design and was rather unpleasantly surprised to have to move the spinny blocks foward onto the beam. I am looking at chopping the spinny pole some 300mm or so to get some sort slot effect back from the Spinny back onto the main. Do we need the pole at max length on these boats ?

The downsides of moving the beams back are lack of crew operating room and more reliance on volume way back to cover the crews weight,the upsides are less volume needed up front and if the pole is cut, less uplift from the Spinny.

Longer pole = more faster. Always.

Even with my Goodall spinnaker from 2004 I used blocks on the main beam. In the last few years to spi's have only become shorter in the foot.

Do we need the pole at max length on these boats ?

Actually, we never did. That rule was only included in the F16 rules to satisfy Texel and SCHRS handicap systems that have some formula that determines max spi pole length.

That formula is a pain in the neck and so I just took the virtual F16 with its mainbeam halfway the hull and worked out that like that we could have a 3.5 mtr spi pole and still not break the Texel or SCHRS rules. At that time, from comparisons to F18's, I already knew that we would be using shorter poles. Mine is actually 3.25 mtr. and seems to nicely balance the boat. I did try 3.5.mtr but the leehelm became a problem. I tried several intermediate positions as well, but 3.25 mtr worked best and then I still have to place my last blocks on the main beam. This does clear up the area around the side stay though (an unexpected benefit).

I'm still convinced that 3.50 mtr spi poles are too long for F16. I mean, you can sail with that, but the optimal length both balance and speed wise seems to be less then that. Remember that our forestays are relatively far back as well, partly due to the use of bridle struts that makes our jib foot come out very low. The slot between the spi and jib luffs is pretty big already on F16's. Equal in size of larger then the ones on F18's.

I recall that Blades, Falcons and others are using less then 3.50 as well.

Wouter

Ok, you go sail with 25cm less pole length and I am 100% sure you will be slower than the full length option.

The helm balance issue is not related to the speed potential, you need to solve that another way. But to shorten the pole because it steers nicer is to make your boat slower.

Come to think of it.

When is that ultimate F16 of yours coming out ?

You have been advising everyone on everything related the F16's over the last ohh 8 years now and up till now that is all that you have done. Talk.

You are proving to be more and more like Douglord with any new post.

I'm kind of busy with a much bigger project...

Well, clearly you are not busy enough. C ya !

Not busy enough it seems.

It is Sunday... I do take some time out every now and then <img src="<>/smile.gif" alt="smile" title="smile" height="15" width="15" />

Now I'm actually interested in Macca's views on this as he does come up with some good sound engineering knowledge at times. Yes Macca can be a pain, but we all have opinions and as far as I'm concerned the more varied opinions aired,the more the development our class will have.

My problem has been as a solo I have no jib and therefore no slot effect over the main. With the very flattish spinny's we are now running, downwind the spiny is now so far foward and out that there will be negliable slot effect on the main, drop the clew back a bit and the sail combination now starts to look more like a screacher and main with a better slot.

Views and sail set up knowledge would be appreciated.

On the m20 we made a 1m longer pole than std. Was always better. Yachts have the same issue, longer pole faster and deeper is the result.

To deal with lee helm you have several options. Most effective is to move boards forward, a 25cm longer pole is usually offset by 5-7cm forward with the board. not so easy to do but most F16 designs I have seen are on the aft side of fast from my observations. Particularly the taipan which is what Wouter is basing his observations on.

You could fit higher aspect boards in the original cases, this will have a similar effect.

Macca, Are you saying that on a boat with lots of apparant wind, that there is no slot effect from the Spinny over the main and one would be better utilising the lift from the spinny to get the bows out more ( less drag )

There are other ways of getting lee helm or weather helm out of a boat as well such as simply moving the rig more upright or back ( or even moving the base from its usual position on the crossbeam, or simply balancing the rudders themselves better by altering their angle of incidence slightly.

Forget the M20 Macca and lets talk F18 A Class type of knowledge which are much more compariable to the F16's

If the boat is balanced and fast upwind but has lee helm downhill then it's not so good to mess with mast rake or rudder rake, it is much better to move the board position forward. It will have none or super small effect upwind (In a reasonable range) but will fix the lee helm.

The slot effect is minimal compared to the increase in air to the front of the kite. There are two things that make you faster downwind:-

1. Longer luff length
2. Longer pole

If I could have a 4.5m long pole on the F18 I would. But right now I will be happy that I can paint my boats <img src="<>/smile.gif" alt="smile" title="smile" height="15" width="15" />

Moving the board forward will I guess move more effort onto the board and away from the rudder, the A's seem to have such small boards that the A has to take some of the loadings onto the rudders to compensate and the rigs position becomes far more critical to balance things up a bit.

The F18's seem to be going the other way with almost all of the lateral effort placed on huuuuuuge loooooooong high aspect boards with diddy small rudders just touching the water at the back. I guess thats all to do with the change of balance of the boat when that big spinnaker goes up.

Still not convinced about the spinnaker not forming some form of slot, the Shadow used to have a mere hankerchief as Spinny run straight from the bow, it was a very fast boat considering how little sail area it had. The new X version seems to be more normal in its spinny arrangement and seems to go just as well with a larger area.

I guess one will have to give it a try some time, I guess just like being able to paint your boats ( thought that had been resolved in your favour )

Make you free of thinking of

slot effect

.

The first sail is always in the upwash of the second one, which is always in the downwash of the first one. The more seperated the sails are the lower the drag by the way. But aerodynamic drag is not very important on downwind legs.
To increase lift the slot must be very narrow (about 40 mm to give you a number), stable and form a convergent nozzle with the mast. All of this is not present on todays soft sail designs, hence no slot effect.
Hence, as macca said, a longer pole is better (for exact the reasons he mentioned above) as long as you can steer the boat.

Another question is, is leehelm a bad thing (a bit of lee-helm, not massive)? I have the feeling that with leehelm the rudder pushes the stern down and bows up. Hence you can have abit more power in the rig before you start to submerge.

Cheers,

Klaus

I wish you could tell that to both texel and SCHRS as to regard the slot effect. Try inputting a 14 m main and 3 m jib and then a 17 m main only, into there calculators and there is considered to be a huge difference.

I am sort of getting very confused about this whole scenario of slot and non slots and jibs and thingies <img src="<>/cry.gif" alt="cry" title="cry" height="15" width="15" />

boards on the Taipan arre far back as the V-ed bows runs deep and narrow like a plate, but the aft sections have rounded keel. There is always a play between boards, rudders AND the hull. Rounded keel line on the bow required different board placements. Can 't easily compare board positions on boats with significantly different keel lines.

I shied aways from making complete new daggerboard wells over gaining 0.25 mtr pole length. Sue me !

BTW lots of leehelm is bad under spinnaker as rudders act like a brake then. I know because I tried. My current setup is the fastest without completely rebuilding the hulls or the daggerboard wells.

Wouter