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dougculnane

Next Generation International Moths.

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OK Anarchists lets thrash out design ideas for improving on the present generation of Moths. The themes and ideas I would lay down for starters are:

 

Weight reduction.

Windage reduction.

Increase the Instability for more righting moment.

Control system refinements.

Rig improvements.

Sailing techniques.

...?

 

What ideas are worth trying (or trying again)?

 

Wing masts.

Aerodynamic wings.

Anhedral foils.

More angle on the wing bars or less.

Smaller hulls.

Shaven heads for lower windage.

Learning to sail the bloody things.

More Blogs.

Better spelling.

...?

 

What are the red herrings and what are the next gains to be made, or is this thread just adding to FOF?

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Doug,

Your list is pretty comprehensive.

 

The end result might look like those ice sailors who stand inside their wing sails.

 

Or how about lay down skipper position within the hull with full aircraft contols: pitch, roll and yaw as well as sheeting, maybe mostly automated.

 

My immediate next step is less hull, less wing structure, and less rigging, less windage, less weight, proof of concept protoytpe done and dispatched, serious construction maybe this year.

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Good to hear you are thinking of building again.

 

I too am think that at the moment less is more. Things like the tiller extension need to be reduced in diameter to save windage. It will be interesting to see what other parts of the boat can be reduced. Certainly the wings could be smaller as our seating position is more static now that control systems are better. Maybe a fairing for the sailor to hide behind is good too. However the width rule thing makes hanning most of the body out over the side inevitable. Unless there are better ideas...?

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What would be required to get rid of the spreaders? Do they really do that much?

In a couple weeks Bram should have a good idea if a Swift mast can hold up without spreaders. If it works well with a masthead kite, it should be fine on a Moth. You might find going to an unstayed rig with bend and flex similar to windsurfers work. The hard part is building something to hold the mast up that is as light or close to the same weight as the rigging on a current spar. It might be interesting to see what would happen with a DN style rig but then a DN will go 3X the true wind at times.

 

I think drag reduction is still a good area of focus. Some weight might be saved in removing things adding drag but unless someone has a line on Unobtainium, You're probably getting close to the limits of the current technology.

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What would be required to get rid of the spreaders? Do they really do that much?

 

I do not know. I think the masts are getting stiffer (not sure) and smaller diammeter (I think Si Payne has a new low windage mast). Getting rid of the rigging would be great but I am not sure how you could support the mast as well. Maybe we will end up like the ice yachts with the bendy mast that curves to tighten the leach...???

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I do not know. I think the masts are getting stiffer (not sure) and smaller diammeter (I think Si Payne has a new low windage mast). Getting rid of the rigging would be great but I am not sure how you could support the mast as well. Maybe we will end up like the ice yachts with the bendy mast that curves to tighten the leach...???

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Diamond Doug Culnane-don't tell me you've given up on this "brillinat" idea(!): (sorry about the spelling)

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----------------------------------

Diamond Doug Culnane-don't tell me you've given up on this "brillinat" idea(!): (sorry about the spelling)

 

 

Do you honestly think this post makes you look aything less than a complete twat.

 

This idea was so far beyond anything you've come up with, and let me remind you, he built it and it worked! Problem was it wasn't as good as current. OK, move on. Which he did.

 

This guy gets out there and does it. Now fuck off from this thread, nobody wants you here.

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The Diamond project is something I am very proud off. I has not sailed my Moth for 10 years. I built a legal surface-peirceing set of foils in my bedroom 100km away from my boat. Fitted them at Lake Garda and tested it. Broke it. Fixed it and flew again. I did the event in lowrider mode so I could race properly and came 2nd low rider.

 

This is my thread do not ruin it so:

Fuck off Doug.

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Back on topic.

 

I do not thinkg the Diamond configuration is goining to lead anywhere, having tested it and the state of the art I thnk the Diamond would not overtake the systems as they now are.

 

Are there any other foil configuration ideas out there?

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Has anyone tried something shaped more like a tuna or swordfish fin? It seems that there might be some reason to follow the natural world where some fish can swim close to 30kts for short bursts. They all seem to have a similar configuration and shape to their tail fins. Where I have a problem with this is an effective way to adjust the AOA without requiring to strong of a force from the wand. I've always wondered if we could learn from the natural world and emulate some of their control systems and shapes.

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Has anyone tried something shaped more like a tuna or swordfish fin? It seems that there might be some reason to follow the natural world where some fish can swim close to 30kts for short bursts. They all seem to have a similar configuration and shape to their tail fins. Where I have a problem with this is an effective way to adjust the AOA without requiring to strong of a force from the wand. I've always wondered if we could learn from the natural world and emulate some of their control systems and shapes.

 

We started with square foils for ease of build and then went to eclipse shaped foils. The hindge stops the sweep back but now that there is no hinge on the rudder I think is would be good to do this on the rudder horizontal.

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Reduction in weight and windage of the hull will only go so far, as the size and weight of the skipper is probably the biggest factor here. Phil's unstayed masts seem to work fairly well, but after recient actual on the water foiling experience (as opposed to a theroetical wet dream that some others have), I am now very much aware that leach tension plays a HUGE role in upwind VMG, and I think that an unstayed mast would compromise this too much compared to the current rigs. To keep leach tension you would need to stiffen the mast considerably and then you would narrow the effective wind range back to what the sails used to be 7-10 years ago.

 

That said, knowing Phil he will probably prove my "unstayed mast won't work upwind" theory is completely wrong with chainsaw III.

 

Foils have a significant role to play, and I think that we are heading in the direction of multiple foil sets that are optimised for various conditions, e.g. an early liftoff set for marginal conditions, and a low drag set for high winds. Look for new designs here.

 

I also think that we are heading down the road of multiple rigs, especially for the lighter guys.

 

Continued developement and optomisaiton of the flap controls will occur, much like shock absorber settings in a racing car, with different setups for different conditions ... flat water, big waves etc. There won't be a mid ship wand, because it will not be proven to be faster than a bow wand.

 

We might see a move away from pocket luff sails back to tracked masts.

 

Red Herrings:

 

Flapped vs raking rudder - both work fine with no noticable performance difference either way.

The F Box - unless you can adjust the angle whilst sailing.

Bladerider is faster than everything else - they are damb sexy boats, but they are no giant leap forwards now that the top guys have caught up again.

Rudder fences - A stopgap solution to a problem that needs to be solved with a different rudder section raked forwards.

 

Learning to sail the things:

 

This is where the big gains are for a lot of people at the moment. If you can't keep it in the air the whole way around the course and nail every gybe and tack you won't be up there at championship level.

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I think the most effective process would be to reverse the order.

 

Learn to sail. Software seems to be the biggest single factor in winning. After all, the top guys are top in almost any boat the step foot in.

Tuna shaped rudder foil.

DN style rig.

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small penny worth from the Gulf. Now it is getting too hot to sail in any kind of neoprene ( i was out this morning at 7 30 am in boardies) can we put an AC on board???

 

Seriously my spelling is shit but i am not too bothered about that.

 

I would like to try Duel wands and duel flap movements. This needs to be coupled with longer wands to get higher out the water to achieve more moment for upwind sailing.

 

The Duel wand idea being... here we go........ when healed to windward, the windward wand would do less work than the leeward wand, giving even more moment for you, and even LESS hiking than i do now. i know what i mean but describing is crap.

 

Also, i would like to put different trampolines on my boat, i would prefer netting, but small netting to let the breeze go through it. Would also like a much lighter sail to stop weight on the top of the rig, hence making it much more responsive.

 

There is a lot more shit i would like to do but i cannot remember what it is right now, very much concentrating on sailing as much as possible with lead up to Weymouth.

 

In terms of technique, i have changed the way i tack today, instead of trying to bring the boat flat with my bodyweight before trying to foil tack i instead now sheet the living daylights of of the main and the millisecond it come flat (also by this point i am 100% at the back of my wing) i chuck it over as fast as possible. This works way better as you have way more power to keep on the foils all the way through the tack instead of stalling and dropping off! You do however, when you get it a little bit wrong wind up on a broad reach on the new tack.... i am still working on that though!

 

made a small adjustment to foiling gybes as well, helps tons,cannot be bothered to write it down though! Am also now sitting much further back downwind and instead of bearing away immediately when a gust hits, start to hike it out like a laser a tiny little bit to accelerate before taking my apparent! Not sure if this is faster yet, Glenn keeps breaking shit so cannot test it. And my velocitek died in the round the world attempt.

 

Anyways, some food for thought!

 

Give it a rest doug Lord, your an idiot!

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The Diamond project is something I am very proud off. I has not sailed my Moth for 10 years. I built a legal surface-peirceing set of foils in my bedroom 100km away from my boat. Fitted them at Lake Garda and tested it. Broke it. Fixed it and flew again. I did the event in lowrider mode so I could race properly and came 2nd low rider.

 

This is my thread do not ruin it so

=====================

Gee ,Diamond Doug, I hate you see you give up so easily-even though if you studied a little more like about surface proximity drag and how foils actually work you would know how very ridiculous the original concept was. It never worked the way you thought it would-do you want to know why?? You don't want somebody coming into this thread telling you what an absurd ass you really are ,huh?

"No one cares about 2.5 chords below the surface. I do not care about theoretical wave on the surface drag shit.

 

Doug get a Moth and go sailing. Untill then stop talking with athority about about stuff you do not understand fully....."--from the C Class thread by Diamond Doug Culnane(spelling included at no extra charge)

-----------------------------------------

You're an ass: you personally attacked me w/o knowing a thing about me; you dissed my work w/o being able to say what was wrong with it. You discuss foiling only in terms of your limited Moth experience and your even more limited design experience. You act like Gods Gift to the Moth Class when in fact you are the notorius Diamond "Doug" Culnane" whose ability to discuss anything is limited by an inability to write, spell and discuss details like a normal person. You could have approached me in such a way that we could have discussed ideas and perhaps even learned from each other. Instead you approached me with your punk ignoramus hat on full of horseshit. So be it, Diamond Doug,Moth boy.

-----------------

You really should try to understand manual control and a midship wand.

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=====================

Gee ,Diamond Doug, I hate you see you give up so easily-even though if you studied a little more like about surface proximity drag and how foils actually work you would know how very ridiculous the original concept was. It never worked the way you thought it would-do you want to know why?? You don't want somebody coming into this thread telling you what an absurd ass you really are ,huh?

"No one cares about 2.5 chords below the surface. I do not care about theoretical wave on the surface drag shit.

 

Doug get a Moth and go sailing. Untill then stop talking with athority about about stuff you do not understand fully....."--from the C Class thread by Diamond Doug Culnane(spelling included at no extra charge)

-----------------------------------------

You're an ass: you personally attacked me w/o knowing a thing about me; you dissed my work w/o being able to say what was wrong with it. You discuss foiling only in terms of your limited Moth experience and your even more limited design experience. You act like Gods Gift to the Moth Class when in fact you are the notorius Diamond "Doug" Culnane" whose ability to discuss anything is limited by an inability to write, spell and discuss details like a normal person. You could have approached me in such a way that we could have discussed ideas and perhaps even learned from each other. Instead you approached me with your punk ignoramus hat on full of horseshit. So be it, Diamond Doug,Moth boy.

-----------------

You really should try to understand manual control and a midship wand.

 

You got him there Doug, a photo of yours foiling would have just been icing on the cake.

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Doug Lord,

 

Do I really have to be your Mac Daddy and come over to this thread and bitch slap you here as well? Is your fanny not raw enough from the last session I administered?

 

Is it not enough that you are devoid of humor, bereft of functional ideas and God knows, boat building challenged to the point where it's painful to see your total inability to follow a project through to completion?

 

Fat Bubba.. get something like a real life and not this imaginary Barbie and Ken thing you do all day with your fist and your Mommy's soiled panties. Mouth breathing is not compatible with boat building.

 

Yes, gentlemen... it has become more than clear that the only way to halt the Fat Boy in his tracks is to beat him severely about the head and shoulders. My sincere apologies to those so offended by the post content (well, save for Doug Lord, the EyeGore of the boat world)

 

DL, go to your little imaginary shop and get something done for once in your life and then, my dear boy... show us your pretty pictures of a complete and SAILING ON FOILS boat project.

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Lord,

 

Culnane has actually come aboard and posed QUESTIONS which are relevant to boat performance and improving it.

 

All I've seen you do is post ANSWERS to questions no one ever asked nor will they ask, accompanied by the same 6 fucking pictures over and over, ad nauseum.

 

Culnane actually had the balls to sail his own stuff, and when he realized he was pissing in the wind, he got realistic and moved on to other things which would improve the class, something it seems you have a real problem doing.

 

I don't know either of you personally, but from what I've seen here (and by the way, on RCSailing too) Culnane seems to have more IQ in his nut hair than you seem to have in your brain. Culnane has shown that he's interested in moving the class forward on a realistic basis, without resorting to alien technology from the planet Zoldar. All you've done is present yourself as a magnanimous cunt.

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if and when i build a new boat, i think there are a lot of gains in having multiple centreboards. reducing lifting area for days over 15knots has big potential gains both in drag reduction and control.

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Ok there are to many people with the name Doug here. :blink: There can only be one! :ph34r:

 

I know which one I want....

 

 

Has anyone in the moth class looked to hardsails? I feel like the efficiency gains there could make up for the extra weight. The only consideration would be the crashes, but durability can always be made added...

 

"You discuss foiling only in terms of your limited Moth experience"

 

Pot, meet kettle.

 

I personally would rather be known as someone who came up with a shitty idea and tested it, sailed it, realized it didn't work, then came up with a better one that someone who comes up with shitty ideas, doesn't test them, then blabbles on about nothing.

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I know which one I want....

Has anyone in the moth class looked to hardsails? I feel like the efficiency gains there could make up for the extra weight. The only consideration would be the crashes, but durability can always be made added...

 

"You discuss foiling only in terms of your limited Moth experience"

 

Pot, meet kettle.

 

I personally would rather be known as someone who came up with a shitty idea and tested it, sailed it, realized it didn't work, then came up with a better one that someone who comes up with shitty ideas, doesn't test them, then blabbles on about nothing.

 

 

Right now I think that hard wings are more suitable to stable platforms.

 

What did not work about the diamond foil?

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What did not work about the diamond foil?

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Look at Burvills boat below-note the area of the windward foil. Now look at the BOTTOM part of the diamond. Diamond Dougs "theory" was that the boat would sail on the bottom of the diamond after it got going-and therefore be faster than Burvills boat or an Illet bi-foiler. I would normally not diss anyone elses work like some ignorant assholes have dissed mine-but the Moth Boy has made himself the exception to the rule-but I don't like playing this role.

The guy has merit and so do some of his ideas.

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-----------------------------------------------

Look at Burvills boat below-note the area of the windward foil. Now look at the BOTTOM part of the diamond. Diamond Dougs "theory" was that the boat would sail on the bottom of the diamond after it got going-and therefore be faster than Burvills boat or an Illet bi-foiler. I would normally not diss anyone elses work like some ignorant assholes have dissed mine-but the Moth Boy has made himself the exception to the rule-but I don't like playing this role.

The guy has merit and so do some of his ideas.

 

 

did it ever line up against non foilers like Bretts boat? It seemed to foil fairly well so I am not sure you can just throw 'failure' at it.

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If people are unaware, there is a rather handy ignore user function on the board.

 

Go to My Controls (top of the page)

On the left, the fourth item down in the bottom panel is Manage Ignored Users

Add the name of any/all the users you wish to ignore. Click Update Ignored Users

You won't see posts by anybody on the list. Unfortunately, however, you will see posts from ignored users if they're quoted by others.

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This is coming from a total newbie with 0 foiling or moth experience but a growing interest. That being said the following might be a very DL worthy idea so apologies in advance.

 

Foiler design for early lift or speed is discussed earlier in the thread. How about changing foiler profiles on the water on demand? Many aircraft have moving moving leading edges on their wings which act to change the airfoil and work as spoilers etc. I am imagining it could be possible to do something like that for the moth foilers to promote early foiling and then reduce drag as speed increases. Has this been considered despite the mechanical challenge it would pose?

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A couple of ideas in my guess at the order of difficulty in execution:

 

1. Increased righting moment through the use of windward heel. Foiling moths are one of few classes that no longer sail fastest bolt upright (in all conditions). Windward heel moves the centre of lift to leeward while moving the helmsman to windward increasing the righting moment that can be extracted from the configuration (and also unloads the vertical foil, reducing the chances of ventilation).

The righting moment could be extended by increasing the vertical distance between the horizontal foil and the helmsman. Pushing the foil further down would increase wetted surface and make an already highly loaded foil even more highly loaded so why not lift the hiking position by 10-15cms? I know from my moth experience that high wing bars make bringing the boat flat from a heeled position difficult as they limit the distance the helm can get off the centreline. My suggestion to this is to have wings with a kink. Flatter in the middle with extensions that project outwards and upwards towards the tips. This way the helm can use the flatter sections in the middle for those fiddly slow speed righitng problems but still get out further from the lifting foil when veal heeling. A single wing tramp might not work on a two section wing so perhaps it need only go out as far as the kink and then have a gap out to the wing end. This might also reduce windage. This idea wouldn't be too hard to test.

 

2. Tapered vertical foils with low drag ultra-thin sections on the lower half to reduce drag when foiling. I haven't seen a foiler stall the vertical foil when travelling at speed so could thinner foils be used? Current foils might already be at the technical limits of the materials - could a steel foil be made thinner than carbon? Titanium? This all sounds difficult for the home builder and a bit expensive really.

 

3. Vang loads are currently transmitted to the hull and wing bars (on most boats) via the mast stump. The hull and wing bars have to be built strongly enough to take the vang loads from angles ranging from fully sheeted in to the main eased right out. Could the mast be extended (and obviously stiffened significantly) right down to the vang attachment point so that the hull and wings do not need to be built to take the large load? Support for the wings might be an issue here, I don't really know.

 

4. Veal heel is reducing the effective area of the rig. Can a light weight canting mechanism be incorporated to bring the rig back vertical when the hull is heeled to windward? At least the rig would always be being raked to leeward which is more likely to be easing a control line than pulling it on!!

 

5. The hull of a moth doesn't do as much as it used to. Better foil control looks like it will increase the amount of time spent in the air, further reducing its importance. Can the structure be put together in another lighter way? Kitesurfing kites use inflatable bladders to create rigid structures. Can the same be done for some parts of a moth hull? Laminates can't get much thinner without compromising durability, could a bladder containing air under pressure help support very thin hull laminates or replace them in some areas? Could a laminated kevlar sail cloth and high pressure bladder be used? This idea is pretty weak when you consider the problems associated with mounting two foils in fixed relative positions. Still a curious thought though.

 

6. Kiteboards and "airchairs" are using a single strut hydrofoil and managing pitch with a tail assembly behind the main foil. Could this be done on a moth? I'm imagining an aeroplane type foil configuration with a single vertical strut coming up somewhere from the "body" of the plane. Reduced strut drag and consistency of angle between the main and rudder foils are the advantages that might come from this. It would be super complex to build and require multiple controls extending down the single strut. For extra complexity you could remove the horizontal foil from the rudder, shorten it up so that the normal transom mounted rudder comes out of the water when foiling and have a small rudder attached to the hydrofoil tail assembly which does the steering when on the foils. (OK - I admit this is all sounding pretty fanciful and probably not the "next" generation)

 

 

While I think the ideas above might have some technical merit I think there is a lot to be said for simplicity on the race course. That might make all of them non-starters. Occasionally though the advantage associated with a complex device pays off (like foils). The proof is in the testing I guess.

 

Doug C - good on you for building & testing ideas back when optimal configurations were not obvious. (I wish I could find the time to do the same).

 

Cheers,

 

Munter.

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all quite valid ideas monty...

 

the inflatable hull idea might work (there's already an inflatable cat class raced in the UK called a catapult), but I doubt that it would be any lighter than current construction methods by the time the inflatable boat were made comparably durable. The only advantages would be in transport (imagine bringing your boat with you as carry-on luggage!!!) and perhaps a slight reduction in cost, but given that the greater part of the expense in these things is the rig and foils the overall cost effect may be negligible.

 

The reason why airchairs, foiler windsurfers and foiler kiteboards run the tailplane foils is to try and keep them more stable in pitch as the only lift control they have is the pitch of the board... moths are OK at the moment by virtue of the fact that the boats are sailed when not standing up... so adding the tailplane may simply be extra drag. DL has made a tailplane style main foil for the flying park bench, so I guess we'll see how it goes if his 'boat' ever sees the water.

 

There is a foiler in the UK with kinked wings (the wings have been kinked downwards at the ends instead of upwards as you suggest). The jury is still out on that one... it was done as an afterthought as the wings were originally miles too high when first made. Looks cool though; perhaps some bladder moulded 3d curved wings (think bladerider wings with curves in both the transverse and sectional planes) would be the go? They'd certainly look the ducks nuts!

 

The canting rig is well within the realms of possiblility; I guess that it could be done as a modification of the tricky early-90's autorakers (as per how the good doug c had his rig on tomahawk when it was first built, drawings are available on his blog)... the only problem with keeping the rig vertical would be that it would remove any vertical lift component from the rig that healing to windward gives you. Also on a moth having a slightly reduced effective area sometimes isn't a bad thing - even the top guys find themselves burning off power to gain control sometimes.

 

The vang loads really aren't that much of a problem at the moment; however one thought would be to try a i14/12 footer / 5.5m style strut vang to open up the front of the cockpit and perhaps make the boats a bit safer that way?

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The way Moth foiling is going, do you really even need a hull? I was thinking about waterstarts on shortboards when I came up with this one

 

:blink:

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The way Moth foiling is going, do you really even need a hull? I was thinking about waterstarts on shortboards when I came up with this one

 

:blink:

 

well you need something to sit on don't you? :huh:

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As a first step, keep the wings, etc. just ax the hull. It looks like the only things that touch the hull are feet, structure, foils, and water, anyway. And the the feet touch how much of the time? Legal to keep enough flotation in the wings to have a semi sinker? There is a sort of purity to it. Maybe you could put some flotation torpedoes where the foils intersect? Then see where things go. How much weight is taken up by the hull, anyway? And all the things that go along with it? Maybe two vertical layers of foils to give enough flotation, etc.?

 

:P

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As a first step, keep the wings, etc. just ax the hull. It looks like the only things that touch the hull are feet, structure, foils, and water, anyway. And the the feet touch how much of the time? Legal to keep enough flotation in the wings to have a semi sinker? There is a sort of purity to it. Maybe you could put some flotation torpedoes where the foils intersect? Then see where things go. How much weight is taken up by the hull, anyway? And all the things that go along with it? Maybe two vertical layers of foils to give enough flotation, etc.?

 

:P

 

so you would have two wings coming off of a mast step and 2 foils? (now we're really talking about moths :rolleyes: )

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experimental non-moth foils designed for jumping

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experimental non-moth foils designed for jumping

 

 

Non sequitur Doug!

 

This thread is about making moths go faster, jumping boats in and out of water with hydrofoils is completely outside the scope of dinghy racing and not related to the thread.

 

Lets keep this thread on focus

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experimental non-moth foils designed for jumping

 

FUCK OFF DOUG

 

The topic is the next generation of moths.

 

If moths had "freestyle" or expression session then maybe it would be valid. But they don't and you aren't relevant.

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FUCK OFF DOUG

 

 

Sorry guys, I told you all that little Douglas had monkeyed with the computer at the observation and therapy facility and had inserted a "stupid post" bot while he was in transit to Switzerland. You'll be seeing a regular stream of this kind of shit from his email addy for the next three weeks while we get him bundled and shipped to the new location.

 

You can expect meaningless copy and repeat picture posts on a regular basis. Don't take it seriously.

 

Douglas will be undergoing a steady application of hot mineral enemas and post lactation swine excretions until he begins to show the kind of behavior indicative of normal humans.

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The rules require a boats own weight plus 75kg of buoyancy in 2 separate tanks.

 

Although A2 & A3 definitions might get the measurer's knickers in a knot (or a wee wet from a good laugh), if one did try a no hull. That's assuming that two separate flotation chambers without a hull wouldn't turn a Moth into a Catamaran.

 

Although wouldn't the SWATH (I hope this is right- what I hope it means is a torpedoish thing underwater, with foils attached) concept work as far as the hull flotation aspects of the rule? With the rest of the flotation in the racks? And the SWATH torpedoish out of the water when foiling? It's a bit unclear how much flotation the racks are allowed. Although I remember a dust up about how much flotation was allowed in the racks before a Moth became a trimaran.

 

Does a Moth hull have to operate at the air/water interface? Doesn't look like it.

 

Paul ;)

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Although, come to think about it, you could have the horizontal rack components acting as secondary low speed/crash recovery foils (in addition to the flying foils) if you went without a hull. They'd have to be pretty big, at least up front, so maybe enough flotation there? And there's a lot of dihedral there already.

 

:lol:

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With all due respect, and I'm not trying to dampen enthusiasm, but doesn't our sky thinking have just a little too much blue in it? Whilst we are thinking incredibly hard, being atleast in the vicinity of the box would help?!

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1) variable geometry foils(configure for the conditions)

2) midship wand(lighter-but see #3)

3) manual altitude control with rudder foil FLAP(preferably) mixed in.

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From my point of view, what is under the water seems fairly well developed but what is above needs work. With that said, within the confines of the existing rig components we are presently exploring the sail development with a wide-sleeve, semi-elliptic 'chop top' planform. I chose the semi-elliptic approach in the lower leech due to the lack of end-plate and to get more area in the head. We'll be testing this sail in the next few weeks both in the SF Bay area and PacNW. In the long run, I like the idea of a rotating wing mast and a more simple sail...

post-9717-1206823186_thumb.jpg

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From my point of view, what is under the water seems fairly well developed but what is above needs work. With that said, within the confines of the existing rig components we are presently exploring the sail development with a wide-sleeve, semi-elliptic 'chop top' planform. I chose the semi-elliptic approach in the lower leech due to the lack of end-plate and to get more area in the head. We'll be testing this sail in the next few weeks both in the SF Bay area and PacNW. In the long run, I like the idea of a rotating wing mast and a more simple sail...

post-9717-1206823186_thumb.jpg

i think its too easy to dismiss what KA have done with the moth sails. they have a huge working range in depth and twist, We simply ask more from the rigs than windsurfers. Powered up in 8knots, controlable in 25kts, all with the one sail.

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Stevo:

The topic is next generation development which inherently opens the question of where improvements might be found. 8-25 is impressive. 7-30 is better so perfection clearly has not been achieved. That leaves room for improvement which is not a dismissal of anything (unless it is already perfect.)

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We can not discard the hull just yet. We still sail in places with sub foiling winds and we still run championship races in sub foiling winds.

 

So far the moth fraternity still consider the class an all weather boat and so the races are on as soon as the committee consier they can set a course. We already are limited by launching difficulties to places with good beaches or ramps, we do not want to be restricted like the sail board racers to only sail where there is more than 15kt winds.

 

Last weekend we had the NSW champs where 5 of the 8 heats were in sub foiling conditions. If we had to wait for wind there would have been no result. There were a few lessons learnt about light wind technique, light wind sail trim and just how well the new foil optimised hulls and sails did not cope.

 

While a lot of effort has been made on going to higher top speeds, the BR success at flying in lighter winds has been very significant. I think this will be the way of the future, fly sooner at some sacrifice to top speed initially, but not necesarilly long term. Reductions in weight, windage and drag are initial aims with improvements in foil and rig design to follow.

 

I think hard sails are inevitable.

 

I still have my 1964 copy of Bernard Smith's book 40kt Sailboat - Aerohydrofoil for inspiration.

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i think its too easy to dismiss what KA have done with the moth sails. they have a huge working range in depth and twist, We simply ask more from the rigs than windsurfers. Powered up in 8knots, controlable in 25kts, all with the one sail.

 

I thought the good guys had 2 sails?

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We can not discard the hull just yet. We still sail in places with sub foiling winds and we still run championship races in sub foiling winds.

 

So far the moth fraternity still consider the class an all weather boat and so the races are on as soon as the committee consier they can set a course. We already are limited by launching difficulties to places with good beaches or ramps, we do not want to be restricted like the sail board racers to only sail where there is more than 15kt winds.

 

Last weekend we had the NSW champs where 5 of the 8 heats were in sub foiling conditions. If we had to wait for wind there would have been no result. There were a few lessons learnt about light wind technique, light wind sail trim and just how well the new foil optimised hulls and sails did not cope.

 

While a lot of effort has been made on going to higher top speeds, the BR success at flying in lighter winds has been very significant. I think this will be the way of the future, fly sooner at some sacrifice to top speed initially, but not necesarilly long term. Reductions in weight, windage and drag are initial aims with improvements in foil and rig design to follow.

 

I think hard sails are inevitable.

 

I still have my 1964 copy of Bernard Smith's book 40kt Sailboat - Aerohydrofoil for inspiration.

 

Not to underestimate Ka, but how many other sailmakers with their resources have designed Moth sails? We have seen the Ka line change significantly over the years - no reason to think that more sail makers will not push that process forward even more quickly.

 

I am not as sanguine on solid wing sails. Sure they are quick but the sail on a moth needs to cope with reality, which is that the sail is in the water a lot on a Moth, or on the beach, or whatever. I am happy to be a follower and not a leader on this front (not like I am much of a leader regardless, but we can all dream).

 

Is there a proposal to limit the number of foils per event yet? These things are really expensive - whether you're talking time or money. And the right foil would confer large advantage, so there is a big incentive. We seem headed for the MSL9 dust-up all over again when someone shows up with two mainfoils.

 

BTW, I heard DL is the guest cook on Iron Chef America this week, and that his piece-de-resistance will be the on-air construction of a monofilm bifoiler, using vacuum infusion of cheese curds into a 12-foot mold machined from solid marzipan. Anybody know when it's showing so I can set the DVR?

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We can not discard the hull just yet. We still sail in places with sub foiling winds and we still run championship races in sub foiling winds.

 

So far the moth fraternity still consider the class an all weather boat and so the races are on as soon as the committee consier they can set a course. We already are limited by launching difficulties to places with good beaches or ramps, we do not want to be restricted like the sail board racers to only sail where there is more than 15kt winds.

 

Last weekend we had the NSW champs where 5 of the 8 heats were in sub foiling conditions. If we had to wait for wind there would have been no result. There were a few lessons learnt about light wind technique, light wind sail trim and just how well the new foil optimised hulls and sails did not cope.

 

While a lot of effort has been made on going to higher top speeds, the BR success at flying in lighter winds has been very significant. I think this will be the way of the future, fly sooner at some sacrifice to top speed initially, but not necesarilly long term. Reductions in weight, windage and drag are initial aims with improvements in foil and rig design to follow.

 

I think hard sails are inevitable.

 

I still have my 1964 copy of Bernard Smith's book 40kt Sailboat - Aerohydrofoil for inspiration.

 

Phil, thoughtful post (as usual). Mr. Smith is a constant inspiration (since 1976, when I found him in the Seattle Public Library), and part of the reason the sky is always blue in my mind, even though I live in the Soggy NW. If I remember right, he went fairly quickly to foils containing the displacement of the Aerohydrofoil- kind of like the Bruce foil, which always beckons, because the thing seems to work, although it never seems to emerge into the mainstream.

 

But how many people predicted the usefulness of foils in the knot regimes you guys are foiling in now? Even what, 3 years ago?

 

And if you combine Mr. Hansen's observations in the arena of sailpower with the comments on the Rocker C class thread- specifically the observation that the rig seemed to need to be depowered in certain situations so the system would be more efficient, doesn't this lead to at least considering that the hull, as it exists right now, is an anachronism? especially given that low reynolds number foils are an unknown country at this point.

 

In a real way, the Moth class is in the midst of a dynamic singularity. Where the light cone of that singularity goes is anybody's guess, and the speed it progresses may be faster than anybody can predict-

 

Paul

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Finally back on line after a house move and some things never seem to change (DL) while at the same time, there are some really interesting threads. This is one.

 

IMO, the hulls themselves are an area that, under the current rules, continual develoment won't see big gains. When you are already dealing with somethiong that weighs 9-10 kgs and only represents 10% of the all up sailing weight, a 2 kg (2%) improvement isn't worth chasing and the windage of the latest generation of boats is such that we won't see big gains there either. To me, this is great because it means hulls won't become obsolete, unless the mast and foil positions change.

 

For me, the big developments will be in 3 areas, the rigs, the foils and the control systems. I believe that the underlying theme for development should be to make the boats easier to sail at 100% all the time and to make the whole package to work more automatically. Contrary to what some might think, we are not tryinmg to develop the fastest Moth but the fastest around a course. If we just focused on top speed, the boats would be very different. We need boats that stay upright around a course in conditions ranging from almost nothing to 30 knots, from flat water to big waves and which can survive a pitchpole plus other abuse that will happen however good we become.

 

Taking the rigs first, I believe that in 5 years time we will still be sailing with stayed masts with prodders and spreaders. Doing away with those elements means you need to add weight to compensate and that weight is in the wrong places. The aerodynamic savings will never compensate. In addition, I don't believe that you can get the required control from an unstayed mast. Phil suggests that hard sails are inevitable. While I agree that they would be faster, I don't think it will happen for a simple reason - we capsize too much and you will not build a hard sail strong enough yet down to a reasonable weight. So, instead, I believe we might see over rotating wing masts up to about 150mm width. Sails will get flatter as we get the boats foiling earlier and eairlier, which moves the priority from power to low drag.

 

Foil and control system development will go hand in hand. Reducing drag will be the theme on foils with attention paid to both tips and also to the joint between vertical and horizantal. I also wonder if we might see a multiple flap arangement. However, whatever moving parts there are will need to be adjusted by "automatic" controls.

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Why not an standard mast adapted to suit a blow up kitesurfer like sail? They would float, and they would be indistructible,until they pop.

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has anyone made a ladder style foil system? (with a foil half way down for more lift in light winds) and annother smaller one at the bottom for when going fast?

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has anyone made a ladder style foil system? (with a foil half way down for more lift in light winds) and annother smaller one at the bottom for when going fast?

brett burvil did it in about 2001 or 2002. didnt work due to the drag when the top foil was at the surface, or so i was told

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hmm when everyone gets good enough to sail around the course with out coming off the foils, you could have a space shuttle system where the launch foil falls off leaving the low drag on. :D

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hmm when everyone gets good enough to sail around the course with out coming off the foils, you could have a space shuttle system where the launch foil falls off leaving the low drag on. :D

 

Nick, there was a tandem sinker windsurfer (I hope- this is in the the far reaches of my mind) that used a system like that, but I cannot remember why. And it wasn't foiled. I think it worked. (?) Maybe Chris249 knows. Chris knows all. Would that be Moth legal? I can see the rule now- " The boat must finish the course with all the parts it started the race with, or disqualification will result." :lol:

 

Simon, if 10 kg is the weight of a moth, wouldn't a 2 kg reduction be 20%? On the other hand, if you factor 2 kg in with the weight of the sailor added, it is a lot less.

 

I guess the no hull thing goes back to the idea of the idealized sailboat that was popular a few years ago in some of the design theory texts- the idea was an una rig with a big daggerboard underneath it. Stoked by that and Mr. Smith's aerohydrofoil, back when I first got my Vacanti software (1996 or so), I spent a couple of crazed, obsessed months designing a Moth hull that was just that- a big daggerboard. And at least on the screen I got it refined out a bit, and the numbers were interesting, esp. at the low speed end of things, and in particular when I made the top part of the foil (where it exited the water) really narrow. It got lost when a virus got into my old hp, but it was pretty tantalizing. I wound up using a wierd thin section that had a pretty sharp leading edge, because with the large amount of lateral area available, I figured that sideways slip wouldn't be a big deal. I even started getting the wetted surface close to that of a skiff Moth with dagger and center boards. Then I saw the narrow hulls, and let it go. The real advantage of the big daggerboard approach, as I saw it, was reduced wave resistance. Keeping the thing from falling on it's nose was it's achilles' heel (in gedankenexperiment land), although I thought adding some horizontal anti dive foils in front would help. One version looked like a small version of one of the plank on edge raters! It was a lot thinner, though. I thought that was really cool. Anyway, the things varied in width, If I remember right, between 3-5 inches. Chickened out though. Buck buck buck....... It didn't occur to me that it could foil. There was another guy in the US who was fooling with a REALLY narrow hull around the early 90's- he had to put anti dive plates on the front of it. Ben Krothe sent me some pics of it.

 

I think Phil is right about solid wings- they won't be made like they are now, though.

 

Paul :P

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Paul:

I saw the tandem speed board you mention while competing in a number of 500m WSSRC sanctioned events in the late '80's and early 90's including Port St Louis Du Rhone, France (before the speed ditch at Stes. Maries de la Mer.) It was very narrow and difficult to get started. The solution was a set of outline-conforming auxiliary rail extensions which made it much wider and allowed the sailors to uphaul or waterstart easily. Once planing, a foot pedal was depressed to jettsion the rails which split away in the front allowing the narrower main board to accelerate away. The 'training wheels' were picked up by a support team and returned to the starting area. It was a pretty interesting construction and fun to watch. There was also a tridem board with three sailors which was not that fast but left a tremendous wake to the dismay of other sailors in their vicinity.

 

On the other topic, I'm wondering if anyone out there has seen an old Scientific American article (probably late 60's??) entitled 'Sailing Without a Hull.' It involved an underwater leeway-reducing hydrofoil device and a kite with the sailor suspended above the water from the kite lines. I've tried to find this article without much success. Seems this arrangement might be viable now by combining some of today's technology like the Moth's sensor-control wand and a skilled athlete like Lou Wainman. Anyone want to work on this?

- Bill Hansen

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Simon, if 10 kg is the weight of a moth, wouldn't a 2 kg reduction be 20%? On the other hand, if you factor 2 kg in with the weight of the sailor added, it is a lot less.

Please don't fall into that trap! Thge only thing that matters is all up weight, including sailor. If you take an average sailor at 70kgs and a boat at 30kgs, a 2 kg reduction in hull weight would be 2% of sailing weight. I guess there is a debate to be had about how much that is worth and how much effect iut has. For instance, on a 505 a 2% reduction of all up sailing weight would be 6 kgs and to take that out of the hull is probably significant. However, I think that in Moth terms, it really doesn't make any difference.

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Paul:

I saw the tandem speed board you mention while competing in a number of 500m WSSRC sanctioned events in the late '80's and early 90's including Port St Louis Du Rhone, France (before the speed ditch at Stes. Maries de la Mer.) It was very narrow and difficult to get started. The solution was a set of outline-conforming auxiliary rail extensions which made it much wider and allowed the sailors to uphaul or waterstart easily. Once planing, a foot pedal was depressed to jettsion the rails which split away in the front allowing the narrower main board to accelerate away. The 'training wheels' were picked up by a support team and returned to the starting area. It was a pretty interesting construction and fun to watch. There was also a tridem board with three sailors which was not that fast but left a tremendous wake to the dismay of other sailors in their vicinity.

 

On the other topic, I'm wondering if anyone out there has seen an old Scientific American article (probably late 60's??) entitled 'Sailing Without a Hull.' It involved an underwater leeway-reducing hydrofoil device and a kite with the sailor suspended above the water from the kite lines. I've tried to find this article without much success. Seems this arrangement might be viable now by combining some of today's technology like the Moth's sensor-control wand and a skilled athlete like Lou Wainman. Anyone want to work on this?

- Bill Hansen

 

I hate it when I want to find something outside the web. It makes the present world seem so much like the dark ages.

 

Cool sail, Mr. Hansen. I guess you know all, too. I am, of course, not worthy.

 

Paul

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Please don't fall into that trap! Thge only thing that matters is all up weight, including sailor. If you take an average sailor at 70kgs and a boat at 30kgs, a 2 kg reduction in hull weight would be 2% of sailing weight. I guess there is a debate to be had about how much that is worth and how much effect iut has. For instance, on a 505 a 2% reduction of all up sailing weight would be 6 kgs and to take that out of the hull is probably significant. However, I think that in Moth terms, it really doesn't make any difference.

 

Humm, so weigh is not important? That's going to make somebody happy!

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Paul:

I saw the tandem speed board you mention while competing in a number of 500m WSSRC sanctioned events in the late '80's and early 90's including Port St Louis Du Rhone, France (before the speed ditch at Stes. Maries de la Mer.) It was very narrow and difficult to get started. The solution was a set of outline-conforming auxiliary rail extensions which made it much wider and allowed the sailors to uphaul or waterstart easily. Once planing, a foot pedal was depressed to jettsion the rails which split away in the front allowing the narrower main board to accelerate away. The 'training wheels' were picked up by a support team and returned to the starting area. It was a pretty interesting construction and fun to watch. There was also a tridem board with three sailors which was not that fast but left a tremendous wake to the dismay of other sailors in their vicinity.

 

On the other topic, I'm wondering if anyone out there has seen an old Scientific American article (probably late 60's??) entitled 'Sailing Without a Hull.' It involved an underwater leeway-reducing hydrofoil device and a kite with the sailor suspended above the water from the kite lines. I've tried to find this article without much success. Seems this arrangement might be viable now by combining some of today's technology like the Moth's sensor-control wand and a skilled athlete like Lou Wainman. Anyone want to work on this?

- Bill Hansen

Yes!!! I remember that thing, I was "big" into tandems at that time (and a 13-14 young little brat), we built a few with the sailing club. Good fun to sail but not quick, and hard to go uphill. The front spot was the best, you'd be ~50cm above the water, depending on the rocker of the board. A moth like feeling now that I think about it. I still have one rotting at a friend's place in brittany. Gybing was good fun too ...

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Please don't fall into that trap! Thge only thing that matters is all up weight, including sailor.

 

Mmmm possibly, but I wonder if something analagous to unsprung weight on wheeled craft comes into play... Even if you're well jammed into toe straps the sailor's torso head and arm weight at least isn't quite as brutally hammering into waves as the hull weight is - there's a bit of spring and flexibility there... Even up on foils the boat is still experiencing some vertical movement in waves and things... But if there is such an effect I imagine its least on foilborne boats and most on fuller bowed trapeze powered craft... I wonder if we should try for flexible sliding weats on ICs(!). Or maybe I'm just trying to kid myself that I don't need to lose that damn fat stomach...

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Weight is everything wrt to foiling in light winds.

 

We are talking about low powered flight here not archimedian sailing, not wave busting, not even power / righting moment. Its about wing (foil) loading and surface area. We are talking about high efficeiency, low powered flying. The fat boys can increase wing size to match the fly weight loadings but the extra wetted surface adds drag and kills speed so take off is delayed. The present size of foils has been found by trial and error to be about right for everyone. Big guys have tried big foils without success. We can make the sail fuller to get power at the expense of higher drag, but it will not help you go fast enough to fly.

 

This was beautifilly illustrated last week at the NSW champs. In +/- 5kts only the fly weights, Matt Belcher, Matt Day, Scott Babbage, Alan Goddard (maybe others I did not see) could get airbourne, and then only for the short duration of the slightly stronger wind puffs. None of the bigger people, even those who are highly competitive in 10 kts, were anywhere near flying. I understand that in at least one race the same thing happened at the Victorian Champs this weekend.

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Weight is everything wrt to foiling in light winds.

 

We are talking about low powered flight here not archimedian sailing, not wave busting, not even power / righting moment. Its about wing (foil) loading and surface area. We are talking about high efficeiency, low powered flying. The fat boys can increase wing size to match the fly weight loadings but the extra wetted surface adds drag and kills speed so take off is delayed. The present size of foils has been found by trial and error to be about right for everyone. Big guys have tried big foils without success. We can make the sail fuller to get power at the expense of higher drag, but it will not help you go fast enough to fly.

 

This was beautifilly illustrated last week at the NSW champs. In +/- 5kts only the fly weights, Matt Belcher, Matt Day, Scott Babbage, Alan Goddard (maybe others I did not see) could get airbourne, and then only for the short duration of the slightly stronger wind puffs. None of the bigger people, even those who are highly competitive in 10 kts, were anywhere near flying. I understand that in at least one race the same thing happened at the Victorian Champs this weekend.

-----------------------------------------------

In the future it would seem that maybe a small rule change could make much more competitive racing in those conditions: why not allow the fat boys to have enough more SA so that their foil loading, SA/ws(when flying) and W/SA was the same as or very close to the fly weights?

post-30-1206918604_thumb.jpg

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-----------------------------------------------

In the future it would seem that maybe a small rule change could make much more competitive racing in those conditions: why not allow the fat boys to have enough more SA so that their foil loading, SA/ws(when flying) and W/SA was the same as or very close to the fly weights?

 

nononononononononononononononononononononononononononononononononononononononono

nonononononononononononononononononononononononononononononononononononononononon

onononononononononononononononononononononononononononononononononononononononono

nonononononononononononononono

 

It's a DEVELOPMENT CLASS.

 

The next development will favor the heavies. I hope. And the lights will complain. Wheeeeeeeeeeeeee!

 

Paul :lol:

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The moth class rules have been very stable for something like 30 years. There have been some minor clarifying amendments and some tidying up, but there has been no effective changes to intent since the amalgamation of the various national classes to form the current International Class.

 

Its always been an 11ft long monohull with 8 sq M in a single sail.

 

With the present boom in interest, in building, in buying and in sailing moths, there is no reason for the class to consider any changes in measurement rules, and there is no interest within the class to do so.

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Weight is everything wrt to foiling in light winds.

 

We are talking about low powered flight here not archimedian sailing, not wave busting, not even power / righting moment. Its about wing (foil) loading and surface area. We are talking about high efficeiency, low powered flying. The fat boys can increase wing size to match the fly weight loadings but the extra wetted surface adds drag and kills speed so take off is delayed. The present size of foils has been found by trial and error to be about right for everyone. Big guys have tried big foils without success. We can make the sail fuller to get power at the expense of higher drag, but it will not help you go fast enough to fly.

 

This was beautifilly illustrated last week at the NSW champs. In +/- 5kts only the fly weights, Matt Belcher, Matt Day, Scott Babbage, Alan Goddard (maybe others I did not see) could get airbourne, and then only for the short duration of the slightly stronger wind puffs. None of the bigger people, even those who are highly competitive in 10 kts, were anywhere near flying. I understand that in at least one race the same thing happened at the Victorian Champs this weekend.

 

Sorry Phil but I have to correct you on this one. Watching the races from the RIB (as opposed to leading the race like you where :rolleyes: ), Luka managed to foil as well, and used that to great effect to come from the rear to mid pack. Luka was pretty much able to get airborne whenever Matt Belcher was.

 

However there was a situation where Scott was up and Matt Belcher tried to match but couldn't get up. So I think that technique also plays a major part, however weight was a key factor. Essentially I think that a good sailor may be able to match a lighter guy that has bad technique, but a light guy with good technique MUST foil earlier with all else being equal, which was your point.

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Phil,

Congrats on your impressive results at the recent NSW states. Can I ask if you were using your gapless upper surface foil and how much you think that may have helped achieve your result? Given that the flaps span almost the full width of the foil, improvements to flap joint design could yield improved foiling performance.

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Phil,

Congrats on your impressive results at the recent NSW states. Can I ask if you were using your gapless upper surface foil and how much you think that may have helped achieve your result? Given that the flaps span almost the full width of the foil, improvements to flap joint design could yield improved foiling performance.

There are a lot of things which help in the light winds. The gapless hinge must have been one of them. But it did not make my boat any faster in foiling conditions when it should have been beneficial.

 

There is a wide variety of hinge line fairness amoungst the fleet. Not all the fast boats are the best so the hinge might not be as important as we think.

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I thought for a while that it would be an interesting development to see how a spreaderless rig would go. Obviously a fairly large development curve there to get the stick and sails working well and learning which buttons to push but I think it'd work with the leech tensions needed to get the sails working.

 

Also, the hulls still need waterline breadth so that they float, but do they still need that breadth at deck level? I guess maintaining rigidity between the wings and C-Board would be fairly limiting there.

 

Also, I remember talk of reducing freeboard, surely thats achievable now?

 

What are the restrictions on the rig? Is there a height/mast length, boom length restriction or is that open? And is there the the old 'cannot be more than 90deg between the luff and head of the sail'? Thinking towards a sail which extends higher than the mast.

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The new boats are lower freeboard than before.

There is a limit on mast length of a bit over 6m. There is a luff length limit too, 5.185m. The 90 deg rule went a few years ago with true area measurement.

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Loads of cool ideas to think about here.

 

I was at a sail-makers this weekend and he suggessed a low windage tramp material. I think that I will go for it and use a mesh that is quite open. This is not a radical development but one idea to try. I will have little hydrodynamic damping with the tramp in the water so I will have to learn to sail, which I agree is where my best development potential lies. I go to the the boat finished so I can train.

 

Solid sails and mutiple foils are interesting but make the boats very impractical. The cool thing about them now is that you can put them on the car roof. The inflatable wing sail would be practical and maybe faster but how you you build it...?

 

I am against the one equipment rule and this thread covers the issue a bit: http://www.moth.asn.au/forum/viewtopic.php?f=11&t=1740

 

I think that the main foil sizes will not change too much because you have to go up and down wind. The boat speed does not dramatically increase (and warent smaller foils) on these points of sailing as the wind increases. If we start reaching races then the foil size could be critical and then you may need a quiver of foils. However championship races will be mainly up and down wind becuase there is more tactics.

 

Thanks for the brainstorming of ideas. It really is good reading.

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You really should Fuck Off.
+1. Until DL can produce a picture like the one below, he should STFU

Flying.jpg

 

The Diamond worked fine and I am proud of the project. There is more info on the web for people that want to read about he project and put it in context: http://www.culnane.net/dc/moth/prj/DiamondFoil/index.jsp

It is a project you should be proud of and just as important, the way you documented it sets a real example. The biggest thing that stands out is just how much others are prepared to share and contribute when you are open and don't treat others as idiots.

 

We are fortunate to be sailing Moths at an exciting times. While this thread has come up with some areas for development, I am more excited about my belief that it is the ideas that we haven't yet thought of that will make the biggest impact.

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If people are unaware, there is a rather handy ignore user function on the board.

 

Go to My Controls (top of the page)

On the left, the fourth item down in the bottom panel is Manage Ignored Users

Add the name of any/all the users you wish to ignore. Click Update Ignored Users

You won't see posts by anybody on the list. Unfortunately, however, you will see posts from ignored users if they're quoted by others.

 

I urge eveyrone to do this. Just imagine no more crap from the lord of the bell ends. Lets all do it, imagine how great it will be, no more input from doug (lord), he'll be ranting and no-one will be listening i'm going to do it now. hooray

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are you going for Hobie like tramps doug or for 18 footer mesh with smaller holes?

 

The guy had lots of hobbie tramp material (or at least stuff close to it). He also had some mesh with larger holes (3mm) but nothing like a skiff netting. I am not sure if I should ply safe with sail cloth or go for the experiment. I think I will experiment though.

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I thought for a while that it would be an interesting development to see how a spreaderless rig would go. Obviously a fairly large development curve there to get the stick and sails working well and learning which buttons to push but I think it'd work with the leech tensions needed to get the sails working.

 

This is where working with a guy like Bill Hansen comes into play. I'm really surprised that none of the guys here jumped at the offer made by Bill to work on some new ideas. The shrouds, without question, are sapping performance from the boat, as well as adding to rigging time along with the possibilities of additional items a skipper can contact in the inevitable crash

 

Also, the hulls still need waterline breadth so that they float, but do they still need that breadth at deck level? I guess maintaining rigidity between the wings and C-Board would be fairly limiting there.

 

I look at the shapes being produced at the hull to deck transition point on the foredeck. There looks to be a ton of drag producing surface issues at that location.

 

Also, I remember talk of reducing freeboard, surely thats achievable now?

 

Looking at the boat, strictly from a design perspective, the existing Moth is pushing a huge, non-productive slab of hull side through the air. Any and all reductions that do not come at the expense of structural integrity, are more than worthwhile in this area. Additionally, transforming the wing frame structures to a suitable aero form will take down the drag signature by increments. Not wrapping the tramp surfaces over the tubes, once they get aero formed will further reduce the drag as will eliminating the tie-down straps, if used to tighten the tramp.

 

I'm not a Moth sailor, I am a designer and I just look at the boat as a form that moves through the air and still has to deal with the water interface from time to time. My interest is in smooth, gradual transition surfaces with minimized drag signatures at every location. I'm also interested in reducing weight. And, yes, 2 pounds are important. If you would balk at adding two pounds to your boat, why would you not be interested in reducing that weight by the same. It is always a benefit to make a lighter racing vehicle as long as it does not jeopardize structural integrity.

 

Has anyone looked at what the skipper wears. Yeah, I know that might sound funny. Consider that thousands of hours of wind tunnel testing has taken place for time trial bicyclists over the years and many changes have been made to the clothing worn and the shapes of the equipment, all in pursuit of the smallest drag signature possible. If Moth sailors, who already operate in a similar wind speed arena, look at the entire package of exposed surface issues on their boats, there will be large gains to be made. Gains that make the difference between winning and losing if racing is the purpose.

 

Soon enough, some skippers will make these changes and then everyone will be forced to do it just to keep pace.

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I see where you a are coming from but i think there are bigger fish to fry here. Cyclists can make gains because they cycle in very steady conditions with bascially static apparent wind angle. sailors experience a range of wind speeds at all different angles so you can't really transfer the practices across very well. What is more the drag on the rig is huge compared to the drag of the person sailing and even the bare hull drag. There is mileage in sorting the deck/hull tramps out but sailing kit and sailor is way down the list!

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Aerodynamic beams on the racks with a track so the tramp doesn't go over the beams might help a bit. Then I thingk a smaller section rotating wing mast might be a good option. I'm not sure it is quite time to discount the windsurfer style sail unstayed. What if you used the wishbone boom to get the needed leach tension?

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