Foiler Design

Rats, Cheesy just posted my comment.

Soooooooooo,

Chris, you said you were one of 4 guys who posited a 3 rule class. One rule was one person as crew. The other was nothing could hurt anyone. And number 3 was? (Drum roll please.....)

And as long as I'm here, anybody tried a Formula Windsurfer type Moth? Within the class rules, of course. Airboats do have low drag. And once airborne (however low that might be) would be hydrofoiling, but in a different sense.

Paul

 

Cutonce/Bistro, you're absolutely right, I know nothing about going into production boatbuilding, never intended to, never wanted to; you can have your backward committees, banksters and so on.
But what interests me is outside the appeal to the masses, conformist and backward box - but the work and ideas of bright individuals designing and figuring out clever ways around problems. This obviously is a field you know FA about, we'll leave it at that and go our differing ways. Cheers.

 

Im guessing that after seeing Adams blog there are literally hundreds of people that have at least started designing wings for various boats, I remember wanting to try it years ago but being put off by people saying they were too complicated and fragile, it has been shown that both of these points are no longer valid. However in light of recent showdowns Im thinking that building a kite course racing board may be a more rewarding use of my time...

 

I agree wholeheartedly that cost is a real factor. It boggles my mind when I have priced carbon cloth. I am actually one of those guys that is actively trying to think of ways to use the absolute most innovative construction techniques possible to allow using cheaper raw materials (thin uni S Glass for a fat structural D section for the front half of segment 1 for example) to build prototype wings just for the fun of it.

I also understand that many are not in a position to do much building on their own. This is why I really like limitations on wings such that they are not a must have item any time soon.

On the flip side, a moth wing is small enough such that the raw materials should be more reasonable than for any other class. A attempt can be made to make cost less of an issue. A minimum required wing weight would make it practical to use at least some glass instead of all carbon. I also like the option to consider something like a mylar "sock" for a wing covering instead of heat shrink film.

Again, I see a lot of potential for wings in high performance small sailboating. The apparent wind speeds for the moth seem to be in the right range where a wing seems to have tons of potential.

I would like to think that smart guys can figure out how to make movement in this direction a good "option" without trashing an entire inventory of existing rigs.

Note that even if a lot of mothies end up wanting to move up to a new boat/wing combination, what they have now it still a very fast and exciting combination. Although a new platform is not cheap, there are lot of people that would love to have one of the current platforms as a first step in joining the moth movement. As such, there should be plenty of market value for existing stuff. This has the side benefit in that a plentiful supply of available used moth foilers would probably help get a lot more of the eager but cost sensitive types in a position to jump in.

 

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Yeah-if you put a lifting foil on it-like the winners at the Trophee St. Clair.
Remember-asinine rules that prohibit foils on kites will never last. You have a chance to be a....pioneer.

 

You are right I do have the opportunity to be a pioneer, although Im not going along the foil route (been done so I wouldnt be a pioneer then) and Im going to try it before I post pics, and then there is a very good chance that it will not work. Where I live foils are not practical, even going to the max fin lenght would not be practical, it just isnt deep enough. I dont see the 500mm fin restriction being all that restrictive. Then after you are done with the board and look at the kites and realise everyone is using production (or at most slightly modified bridles etc) kites there is a huge area of potential development, as a sport it is in its infancy.

 

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The world of high performance sailing owes a debt of gratitude to the Moth class for allowing the bi-foiler concept to grow and develop as it has. It is a true revolution in sailboat design that is simply extraordinary!
BUT: its time for the next step in the foiler revolution-one that will smash all the preconceived notions people have developed because, for the most part the Moth has been the only game in town:
1) "it is necessary to walk a foiler out to deep water" No its not if the boat is designed with retractable foils AND has excellent sea hugging stability
with real buoyancy pods.

2) "it is necessary to build the boat 100% out of carbon" No its not-Bladerider built an all fiberglass Moth but it didn't compete too well with the trick carbon boats. This boat would be a one design class and would be designed to work extremely well with less expensive materials just like the FX did.

There is Phase Two of the revolution just around the corner-an easy to sail, relatively inexpensive, Peoples Foiler. The boat would be comfortable-not a torture chamber. It could be designed as a two person boat that could be singlehanded. Its time that the positive and negative things we have learned from the Moth experience are used to create a real ,popular flying dinghy and the worlds first Peoples Foiler.
Anybody seen AMACS new boats?

 

Rule 3 was that it had to be a windsurfer. The class (or probably the pro scene at the time, with cars and cash up as prizes here) created giant Div 2 boards and similar creations, but it only lasted a few years and that was at the height of the boom.

A Formula style Moth would (as far as I know) have little or no advantage over a foiling Moth in moderate winds (even without cutting 3m+ from the sail) and would be miles slower in winds too light to foil or plane - it would be extremely lucky to finish within the time limit.

BTW re the SA comment about windsurfers. Having spoken to a lot of Moth designers, I can't recall any one of them saying that windsurfer hulls played a part in the design of the skinny skiff Moths.

Some of us have spent some time trying to work out a course-racing longboard with foils. Years ago there was a Mistral M1 copy with foils around here. But since foilers have been legal in boards for years and no one's used them for course racing, it seems to be a stretch to say that there was much chance that the Moths would have created foils if Moths had become a windsurfer class.

 

You make some good points, but are you sure that there's a need for outmoded second-hand boats? There doesn't seem to be a big lack of quite good second hand boats, and they don't appear to be selling straight away.

Certainly at one stage some people were saying that they could not find buyers for boats that were not leading edge. You may need more evidence before you can be confident that making boats obsolete will help the class.

 

Chris- A Windsurfer! (and Div. 2!) How Cool Is That? Actually my point about Windsurfers and foils and Moths was the cross pollination that would have occured- who knows who would have been first? And how fast the other would have followed?

And your comment about a Formula Windsurfing type Moth having "little or no advantage over a Foiling Moth" is a conclusion I have already come to, which Is why I asked. Might be less $$ to build, which means it might proto out faster. And most likely keep up. It would be a slug in the light, at first, at least, but do you think that the wind minimums for Moth racing are going to stay low? And if they do, maybe wings will make up for that? Hoyle, at least, seems to think that wider has advantages for boards, esp. for low wind planing, and at 7' max width, the Moth has width in spades, in the rules. 8' long by 7' wide? Floaty! And a lot lighter. if you don't mind breaking once in a while.

A couple of sheets of 4" thick extruded polystyrene, a shureform, a little epoxy?

Paul

edit- There were a couple of guys i talked to over here over beers that were influenced by the long skinny speed boards, but things were really over by then, at least here. There was a skinny one built in the early 80's that had anti dive foils built in to the bow, so the idea has been around, although I'd have to dig deep to find a pic. Ben Krothe gave me a copy of the pic.

 

Making a lot of boats obsolete too fast is of course very not good. The transition to wings does not require a new boat, but again those likely to be eager for a wing are likely to be the guys that change boats more frequently than the average user.

If there is a big surplus in some areas, the moth has an interesting potential. Not many boats can be packed up in a box and shipped in a normal delivery truck. My time around the water has not been much lately, but around here I have not even seen one on the water at all.

 

I saw one once ... in 2007 ... on the beach in Valencia just outside the beach entrance to the AC compound.

My buddy and I stopped to talk to some guy named Rohan and his mate. In the 15 minutes we were there, NOT ONE of the hundreds of people going through the portal stopped or showed ANY interest at all.

Little guy in rubber suit picks up boat walks down to the water, wades in, and sails off into the spectator fleet. Who knew we were looking at a revolution!

Since that time I have yet to see another foiler of any type other than in photos on the internet.

R

 

A question for Tom Speer (if he is still listening on this channel):

OK so the latest Oracle rudders had a bit of bullet fairing on the front. but the strut was not staggered at ALL. The two-part moth foils tend to have a mortise and tenon at the junction, which requires a bulb/bullet to get enough material there. So the question is, if you go one piece at the T (so you don't need the mortise/tenon), is the bullet any faster than staggering the strut and putting a nice fillet on both the leading edge of the strut and the back of the intersection? I'm thinking not (a la Hoerner). I stretched the local chord of the lifting foil out to fit the foot of the strut, so about 2x baseline chord for the lifting foil. I will add a little fillet to the front of the strut, but then it's going to paint.

Bora said he would put a point in front of any intersection and thought Bieker would too in light of the Oracle rudder fairing, but I think something very similar can be accomplished without a bullet per se (see photos).

Thoughts? I seem to recall decavitator having no bullets anywhere.

 

Still a pretty small cadre of people who sail the foiling moths. P Flados: search on the name Joe Bousquet - he might be in NC, and blogs as "mad mothist". I think there are at least a couple in Annapolis. One guy who built one works at the Naval Academy hydro lab and is a friend of John Zseleczky, who also works there and sails a classic moth. Perhaps his name is Bill ?

 

Bill Beaver, I think

http://www.moth-sailing.org/download/CSYSPaperFeb09.pdf