USA 007
Anarchist
Welcome back Peter!
Coming to Newport this weekend? We are expecting 20+ A's...
Coming to Newport this weekend? We are expecting 20+ A's...
new stuff in the a-class
- Thread starter Lars Schrøder d 13
- Start date
lasersail2
Anarchist
Awesome! We should have close to 20 F18s there, one of my favorite regattas of the year. Come find us after racing... we have free 'Gansett
Jeff Dusek
USF18 Eastern Area Rep
USA 007
Anarchist
Sounds good. Look for the big trailer from Georgia.
mustang__1
Super Anarchist
Would anyone be interested in letting me have a go on their boat this week/weekend in Newport? I will not be making a decision on what boat to get next for at least one more year (waiting 29er worlds in NA next summer), but i have my eye firmly on either a Moth or an A-class. One of the primary problems i'll have with either class is being only 125lbs, but i figure i cant get any lighter and will eventually start putting some weight on when im settled in my new home and can get back in the gym. Foiling or not has no influence on my decision - only entry cost and how much of a disadvantage i'll be at 5-5 and 125lbs. I prefer trapping, though...
USA 007
Anarchist
Come by Sailnewport and we'll see if we can get you on a boat.
-Mike
-Mike
mustang__1
Super Anarchist
will do.
MountainCat
Member
I am a bit surprised to see Chris Field take this action for a rule change seemingly without much discussion from class members and without input from the technical committee. Has the technical committee examined this rule change and do they have an opinion?
IMHO if any rule regarding foiling should to be changed, it would be to reduce the1.5 meter width of the foil exclusion zone. But only after much discussion and consideration.
A-cats have evolved from beach cats which have been traditionally launched from the beach. Insert from below daggerbards would prevent beaching A-cats and would add complexity during launching that may not be desirable. I can't imagine trying to launch through large surf and inserting daggers from below by myself. I am in favor of keeping the insert from above rule to preserve simplicity and maintain continuity with present boats. I believe SHC expressed a similar opinion a few months back.
Opinions?
I hope they can change the rule restricting the foil tips from being closer to 0.75m from the centreline as well. Changing it to 0.5m instead would preserve the boats as multihulls, but allow most of the lift to come from the main foils and allow the rudder foils to be used as horizontal stabilisers.Here is the proposed rule changeroposed Change to Rule 8.2Chris Field has suggested a change to Rule 8.2The current rule 8.2 states -Movable and retractable hull appendages shall be inserted from the top or be capable of being fully retractable into the hull.The BACCA are submitting a proposal to the IACA to replace this rule and replace it with the following;The boat must float in 300mm of water (or words to this effect)At present we have a-cats foiling during racing. This is a fact however, it is only possible with some rather expensive daggerboards designed to exploit the existing rule. We believe foiling this is the future of the sport and should be made as easy and cheap as possible and believe the above rule change will make this possible.The intention is 4 fold:1. to allow an elegant solution to enable foiling, rather than the complex and inefficient methods builders are coming up with at present, to get around the rules.2. potentially enable old hull designs to become competitive again at a low cost. for example the more time the hulls are out of the water during a race, the less relevant the hull shape becomes.3. Allow racing competitive A-Classes at a cheaper cost and encouraging "home-builds" once again (I am thinking here of encouraging youth sailors into the class who lack the money to enter at present).4. The class is a development class and this fact should not be hindered.The reason for inserting the last sentance: the boat must float in 300mm of water (or words to this effect) is so that we can easily launch and land out boats in the way we do at present, safely, using trolleys. If the class allows us to have fixed foils at the bottom of our boat this will become an issue, much like the Moth class.This may also close the door on any potential new designed single handed foiling Cat class developing as a rival.It is the BACCA Committee's recommendation that you vote YES to this proposal, however, as usual, the decision is yours! This proposal has the support of several other A Cat Class associations.--------------------------------------------------------------------------------
Peter Johnstone
Member
- 432
- 1
Krash and Jeff, thanks. Can't make it this weekend. Hope to do some of the regattas this fall and winter.
ita 16
Anarchist
if I can give an opinion, I do not think that the older boats can be adapted to the foil, the cost would be high, the position of the old boards is different from the correct position for the foil, the internal structure of the hull is not suitable bear the load of the foil, update the old boats is very expensive and must be done by expert hands, the result is that all the old boats will become obsolete.
Regards, Michele
Regards, Michele
NED 27
Member
Simplifying the rules will help to update older boats.
We will supply upgrade kits.
Upgrading boats is relatively expensive as you need new cases, new boards and time/money to do the job. Selling your old boat and buying is more conomical in most cases but if you cannot sell your boat or if you attached to her it can be done.
I agree with Michele that some older boats are structually not up to par if you start flying these in a bit of breeze. The hulls do slam hard on the water and you better have a carbon skin and preferrably a nomex core.
If not treated to bad, older flyers,scheuerers and carbon Bims will become better boats after an upgrade.
To add J-boards you have to change the daggerboard cases but then you can use all type of daggerboards.
In older boats with straight or curved daggerboards you can easily put in L-style boards from the bottom.
The 1,50 rule should be abolished as well as it makes it difficult to make high aspect ratio tips. In the last boats the daggerboard cases our on outside but not in older boats.
Sofar the J-board solution is the most allround solution. You can sail on 4 foils and have amore foregiving boat which does fly sometimes.
Landy and Stevie did not have J-boards at the Europeans, but the nobody can have missed the performance of it downwind.
Manolo has shown you can win races, you has Donald Beike in Germany, Sjoerd Hoekstra in Italy and Mischa in Spain and France.
We will supply upgrade kits.
Upgrading boats is relatively expensive as you need new cases, new boards and time/money to do the job. Selling your old boat and buying is more conomical in most cases but if you cannot sell your boat or if you attached to her it can be done.
I agree with Michele that some older boats are structually not up to par if you start flying these in a bit of breeze. The hulls do slam hard on the water and you better have a carbon skin and preferrably a nomex core.
If not treated to bad, older flyers,scheuerers and carbon Bims will become better boats after an upgrade.
To add J-boards you have to change the daggerboard cases but then you can use all type of daggerboards.
In older boats with straight or curved daggerboards you can easily put in L-style boards from the bottom.
The 1,50 rule should be abolished as well as it makes it difficult to make high aspect ratio tips. In the last boats the daggerboard cases our on outside but not in older boats.
Sofar the J-board solution is the most allround solution. You can sail on 4 foils and have amore foregiving boat which does fly sometimes.
Landy and Stevie did not have J-boards at the Europeans, but the nobody can have missed the performance of it downwind.
Manolo has shown you can win races, you has Donald Beike in Germany, Sjoerd Hoekstra in Italy and Mischa in Spain and France.
Each time I go sailing, I have to "capsize" the boat on the beach to hook the sail at the mast top, so it will not add any problem to insert the L centerboards from the bottom.
Along with removing the 1.50m rule, this is the best solution to preclude a singlehand18 Cat to appear with full foiling potential
Cheers
Along with removing the 1.50m rule, this is the best solution to preclude a singlehand18 Cat to appear with full foiling potential
Cheers
AClass USA 230
Anarchist
BACCA will have to submit this rule change proposal for vote at the next IACA AGM at next year's WC in New Zealand. Their proposal must have the support of several MNA's before it can be considered at this meeting. The Technical Committee is a resource of the class and will only get involved at the request of the IACA executive leadership.
As an active A-Class sailor, I think the BACCA proposal is interesting. It seems like this would allow something like an L-foil as long as it does not protrude more than 300 mm when retracted and addresses the concern for easy and safe launching and recovery without having to capsize the boat on the water. Seems like you may have to capsize your boat on the beach for full removal with this approach. Given the conservative nature of the class, I predict the 1.5 meter restriction will remain in place if the BACCA proposed rule change moves forward in the next year and gets approved by the class.
Removing the 1.5m restriction isn't mentioned, so it will remain unless someone proposes another rule change.
But changing it would be a commonsense approach. For example, DNA and Paradox have moved their centreboard cases outboard to gain more vertical lift. This is just wasting everybody's time and money because if the rule changed then you could leave the centreboard case in the middle of the hull and get the same result.
Plus there is the obvious issue that if you go to all the trouble of getting ETNZ style foils with the hook then why not make them large enough to foil consistently.
There is a more technical reason. Pitch stability depends on the difference in the AOA of the main foils and the horizontal stabilser foils on the rudder. This is called the longitudinal dihedral angle. You want the main foils to be at a higher AOA than the horizontal stabiliser foils on the rudder. In fact, most aircraft have the tailplane pulling down and all the lift coming from the main wing.
So restricting the size of the main foils and requiring more lift from the rudder foils is counterproductive. It reduces the longitudinal dihedral angle and makes the boats more unstable in pitch.
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Doug Lord
Super Anarchist
For what its worth, Bradfields foilers are set up with the mainfoil at a nominal +2.5 degrees angle of incidence, with the trailing rudder foil at zero degrees-both set up relative to the static waterline. A characteristic of those boats is that the mainfoil carries 80% of the load and the rudder foil 20% at takeoff-as speed increases the rudder foil unloads until it automatically begins to pull down.
I have just picked up a new to me Scheurer G4 with circa 2008 rig. I want to build new lifting foils for the boat, but I'm not sure what approach is the best to take. The board is currently set up for straight foils, and I'd rather not rip out the old trunks and put new ones in, so I was wondering if I should just build J foils that are retractable a certain amount, and leave a bit still hanging beneath the hull (I don't really care about 100% compliance to the rule). Or I could try and build some kind of controllable incidence foils with wands. I could replace the trunks if I had to, how tough of a job is it?
Which would be the best option for me?
Which would be the best option for me?
I guess there is another thing that you could do if this rule passes, but the1.5m restriction is not changed. You could have asymmetric t-foils on the daggerboards with wands. That way you use the full 0.4m span available for vertical lift. This would be like having two 18 foot moths joined together with beams. I'm not sure that's such a great option because of the expense of having flaps and wands and the complexity of adjusting them.
It's interesting that none of the C class cats for the upcoming championship seem to have chosen this route and I believe it failed when they tried it before. But it's not clear how it would work on the A class compared to the current boats.
So the class needs to think whether they want to allow a little ETNZ style boat or the 2 moths version - or stay as lowriders/skimmers.
It's interesting that none of the C class cats for the upcoming championship seem to have chosen this route and I believe it failed when they tried it before. But it's not clear how it would work on the A class compared to the current boats.
So the class needs to think whether they want to allow a little ETNZ style boat or the 2 moths version - or stay as lowriders/skimmers.
That's what I meant by controllable incidence foils, not sure if that's the correct terminology or not. I was thinking about having the whole foils pivot (similar to the Hobie Trifoiler) which would eliminate some of the complexity of the flap, but would make the case more complicated. As you pointed out, this hasn't really been proven in the multihull development world.
Doug Lord
Super Anarchist
All you have to do is look at the performance of the Hydros Nacra F20c, their new C Class, the Flying Phantom, the 45's and AC 72's to know exactly the right foil configuration and type to use. I don't know where the videos are here but on boatdesign.net they're in "multihulls" in the LAC 2013 thread. Speeds in terms of multiple of wind speed are pretty exciting-like 21 knots in 8 knots of wind or better. Top speed of the NACRA F20c is 32 knots with the three foil system pioneered by TNZ and refined by Hydros for both the Nacra and their C. These new foil systems have a couple of major things in common: Three foils and a SINGLE main foil. They seem to get altitude control thru use of a curved main foil with an "L" foil tied into it doing the grunt work of vertical lift. Based on performance, these foils are breakthrus-surpassing wand or feeler controlled systems in light to moderate air. The Trifoiler and Rave both use dual independent altitude control systems that generate all the RM AND vertical lift for the boat. The new systems ,generally, don't create RM-just vertical lift(and lateral resistance) and are really quite simple.
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cbatchelor01
New member
Just imagine launching your a-cat at the 2012 worlds with 80 other boats in 20 knots of breeze...then imagine having to flip it over on the way in and on the way out....fail
Wait a second, imagine having to do the same thing on and off the ramp in Barcelona last week.
Oh yeah, what happens when you hit weeds or a plastic bag and your race is over because you cannot take your board up to clear the weeds?
No thanks.
Wait a second, imagine having to do the same thing on and off the ramp in Barcelona last week.
Oh yeah, what happens when you hit weeds or a plastic bag and your race is over because you cannot take your board up to clear the weeds?
No thanks.
