you dont have to buy the $2000(not installed) boards!

The A Cat is a developement boat, rigid sails, curved boards, carbon everything, but....they drew the line with foiling. Why? Im sure cost is a factor, but bringing the A Cat to a true foiler would really make alot of boats obsolete. A big percentage of A Catters are sailing on older platforms, probably enough to sway the vote to keep it a more "traditional developement class".
Comparing it to the Moth's probably not fair, at least in the US the Moth is not a very widely raced boat, so therefore stepping it up a notch probably didnt limit alot of boats(at least here in the US)

But is full foiling actually faster?
They used them on the C-Class right?

Full foiling way faster. On the moth the F16 cats in Singapore can't keep up. Passed them to leeward going upwind, and downwind going faster and lower. And the moth only has an 8 sq m sail...

And as for costs of the foils, on the Bladerider and Mach2 the foils and the foil set up contribute to half the cost of the boat (retail is US$14k-$17k). Adding that cost onto the current price of the A would mark things out of reach for an already successful class. Plus the current A class masts couldn't withstand more than a couple of crashes from foil ventilation as you certainly hit the piss hard when crashing.

What I meant was a setback for the development of foiling in beachcats. Not a setback for the A class.

Dave Carlson has a foiling A cat, I think its been around for awhile. Take alook at his Avatar

I think foiling is a dead end for cats, but I love to see people tinkering with it trying to make the technology work well around the course in a cat configuration. If somebody makes it work well enough to beat a Tornado around the course, I would say "lets go!". Preferably with the current aesthetic looks.

Reason I think it is a dead end: Power to weight ratio is not large enough on the common beachcat to give best performance around a course. (I am very narrow minded, thinking about racing only, I admit that)

I have heard anectdotes like taipanfc gives about moth speeds relative to cats, but I have still not heard about a "grugde match" where moths were faster around the course. I dont doubt that the moths can be faster, just never seen any non-biased reports of top moth sailors racing top cat sailors on the Tornado or similar and beating the T? Or M20 or any similar really high-perf racing cat.

Certainly agree about the Moth, the one at our club when he has come out to play, seems to go off on his own after a short while. I think they maybe faster in a very narrow band of wind speed but that is a very narrow band.

Sailing is all about all conditions and not ideal conditions, not sure the foiling Moth is in the " all conditions " club just yet. I'm sure though with more and more foilers about, we are getting a lot of development from a lot of people and not just a few as has been the case and consequently the foilers can only get much better all round boats.

Moths and Cats are very much opposite in terms of how they (Currently) go fast

Moths - reduce ALL drag as much as possible; very light boats, flat sails, and foil to reduce water drag by flying. Current Moth trends are to more aero efficieint boats; suggestions that more speed will be found by using different foils for different wind speeds (Big foils to fly in lighter wind and small foils to fly more efficiently in bigger winds - do not need so much lift as you WILL have more speed, thus smaller foils, thus faster as less form drag)

Cats - Long thin hulls - so "normal form drag rules do not apply". Wide boats to gain rightling momentand so more power and so drive boat fast.

Now, my thoughts are documented on how we COULD make cats faster (opposing foils to create RM).

How might we develop cats to foil without using opposing foils?

1, boats need to be LIGHT to remove drag from creating loads of lift to fly -> Small boats
2, boats need LOW air from drag -> small boats
3, once a boat is flying, we need a low drag (and low power) rig as form drag is low, thus as we do not need lots of power, we do not need lots of RM to control it ->Thin boat once airborne as less aero drag
4, as we do not need lots of power once foiling, we do not need wide (and so draggy) boats ONCE FOILING, but we need a boat that can create RM when needed, but have low form drag when flying - We need wings!
5, Small, not very wide boat, but with wings to create RM when needed = MOTH!

IMO, the Moth IS is "dinghy" solution to foiling. Cats will ALWAYS have MORE form drag. Could we design a boat that was low drag (but never as low as a Moth), that thus had more power that can be used.... I'm not sure.

My view is that the way to make cats considerably faster is to create RM as per "Blue Arrow" with opposing foils mounted mid hull to create RM and thus allow huge power to be carried.


One issue with the moth is that currently they foil in about 8kts true. below this they are dog slow, above this they are VERY quick.

The development for the A-class is limited due to the box rule where the tip distance must be at least 1.5 meter. The curved boards on the A-class could probably make a jump when you get close to 20 knots of speed, but you don't want that....

This is M20 we are talking about, and don't se any reason why they shouldn't use curved board for semi foiling if that proves to be faster. There are no rules for the M20 right now, they use all kinds of rigs and also extra wide boats, so whats the problem if they start to use foils?

I haven't heard about a foiling cat that can beat a non foiling cat of the same size around a upwind/downwind track. For pure top speed a Tornado on foils has proved to be faster than a non foiling Tornado.

One of the M20 on Round texel has two centerboard trunk, one for straigt and another one for curved boards, but it turned out to be a light wind regatta so they left the curved boards on the beach.
/hakan

I'll stick to conventional cat design wisdom for as long as moth doesn't show up at an open water distance race, get out through the surf and beat 51% of the cats around the course.

I don't think it will ever happen. Mind you the Australian portsmouth rating for the foiling moth is 20% faster then the non-foling moth but still on a par with the Hobie 16's

'nough said.

Wouter

I still think you could hook two Moths together with carbon beams, add a tramp, dump the wings, figure out how to manipulate both sails and you'd have a "poor man's" foiling cat that would be a lot more stable than the single hull Moth.

Makes sense to me. However, if the Moth class allowed foils in the wings, the Moth would become more stable and, as a consequence, faster in a wider range of conditions.

From that point the boat would evolve into a trimaran.

Conclusion: cats may not be the ideal foiling platform, but this does not mean that monohulls like the Moth are "the" thing. Trimarans look like a better choice nowadays.

Depends on the definition of Tri....

If moths allowed foils on the ned of the wings, you might end up with either 2 foils (as per "Blue arrow") that allow the boat to create massive RM. OR, you might have 3 foils:

one on each wind to create RM and one in the middle hull to control "Ride height".

Maybe..............

In August last year on Sydney harbour, the moth beat the all the A-Cats in 3 out of 4 races. The first placed A was Steve Brewin who is a quite handy sailor.

Here in Singapore we had a couple of races that were informal (no results taken). More of a reaching course. 3 lap race. First leg to the top I couldn't foil so the F16s scooted away. Then the breeze came in from the side so all boats got fairly much at the same time. F16s were close to a leg away. Once I could foil i easily caught up and won by over a leg.

At first i was sceptical that the moth was that much quicker than an A/F16, but it truly is, with the caveat of the right conditions of course

Look at blog post for June 3, www.rohanveal.com Also has link to the results.

In another single-handed dinghy regatta (no cats), the moth would have still won if handicapped at 51 on VYC. (Source somewhere on SA).

As for getting out through the surf on a moth, well not going to happen. Unless you want carbon pieces all along the beach, haha.

Someone will try foils on a cat. My personal opinion is let some tinkerer/boat nut work out the details of how it works as it will be costly to develop with a lot of time taken up.

Do you have a link to the event? Not going to nit-pick details but I would like to see it confirmed that the Moth is faster around the course than high-perf cats, when comparing apples to apples.

Never saw official results online and I don't think there were any, just reports posted on SA from actual participants on that weekend.

Biggest problem is that multi-boat regattas seem to be exclusionist between cats and dinghies. So going to be hard to find results. But look at the results on the Rohan Veal link. The first 14 skiff guy is one of the top guys at the worlds. All I can say that once foiling the moth is crazy quick in reality to what you would expect. Going deeper downwind than cats with kites and main sheeted near centre and hiking hard is awesome to do. (But trying to sail in non-foiling conditions is an absolute pain and chore).

G'day Rolf we had Greg Wise on a Foiling Moth come here last January for our 15km downhill run from Cape Jaffa. The F18 crossed the start line with spin but not enough wind for the Moth he sat in the water long after I was gone then flashed by at much wider angles than us but unbelievably fast. The wind came up and he caught the leaders at the rounding mark but then the wind dropped out and he went slow up hill so he came 3rd. These photo's show the sequence, the moths in the water as they cross the line in the first photo. The whole fleet's gone in the 2nd and he's caught them at the rounding mark but no longer foiling in the third. As soon as there was enough wind for the spin guys to get on the wire the moth went unbelievably fast. Most of us at the club want to try one.
Notice the F18 is not even in the second photo it was long gone
regards

To all (and not specifically to James)

Just for the record.

I do think the moths are very exiting sail craft and really respect the guys that developped the full foiling moth into a viable alternative to the non-foiling moth.

The fact I have serious doubts about a full foiling catamaran doesn't mean I look negatively upon the moth themselves.

I do believe that partial foiling like the ORMA tris and the John de Vries special are doing is viable for large cats. This involves bruce foils (or curved foils) and only lift the boat up by say 60% at their absolute full speed.

The reason for this are the control issues that arise when more of the boat is lifted and a positive feedback is created between the rise of the hull and increasing the angle of incidence of the foil which in turn ... well the famous foiling jump.

I also have a question for James. Do you feel the VYC rating of 84 is correct for the Moth, considering it is an average that is to be taken over all windconditions ?


Wouter

Foiling has yet to be seen quicker around the bouys for a cat. The Canadian C Class guys gave it a good go and found that the non oiling C was a bit quicker. With a bit more development they may eventually get there, but will they ever become quick enough to justify the poor low wind performance.

Foiling C Class Thread - http://forums.sailinganarchy.com/index.php?showtopic=59168&hl=