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WHY THE FUCK HAVE YOU NOT TESTED THE BOAT IN YEARS YOU RETARDED PIECE OF SHIT?! SHUT THE FUCK UP WITH THIS REPEATING YOURSELF, IN 2 WEEKS YOU WILL HAVE BEEN POSTING THE SAME VIDEO AND 2 IMAGES FO

That is one of the most ridiculous and uninformed statements you could have made!!

dude, Ian HATED you.  He, like dozens of other top sailors and designers, complained frequently to mods - including me - about you until it became obvious that Scot wouldn't ban people for being

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Is there a "full size" trimaran example equipped with the New Zealand style foils on the amas? I've seen computer renderings, has anyone gotten around to actually building one?

See the thread on the Exocet 19 footer. That boat is under construction now in France. It uses UptiP foils on the amas and each ama has a rudder. Don't know how early it will fly the main hull but I imagine that will be key to it's success. Most tri's don't fly the main hull until its over 10-12 knots wind.

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Here is another Chris O spoof, posted under the name Chr!s 0

 

... If you are interested in the plans for any of the aforementioned vessels, or any other design I have seen and subsequently copied, email me at chrisweggiesail@buttcrack.com, I will respond to your request quickly, until the check clears; and after that you will never hear from me again.

 

Easy to see why he wanted to sue, and it's nothing to do with lack of sense of humour. That last bit goes way too far.

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Is there a general rule of thumb when determing the "take off" power required for a particular foil? I ask because I'm interested in seeing how much of a difference there is between the take off speed of say a heavier "low tech" glass cat with an aluminum rig vs. the same boat, same sail area, but a lighter carbon construction. No doubt there is a significant difference, I'm just wondering how much of a difference there is now given the increased sopistication of the foils today compared to Icarus for example.

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Raps, you can use this simple formula from Ray Vellingas book "Design Build Fly" : L=V^2 X S X CL where L=lift in pounds, V^2= velocity in ft/sec squared(1mph=1.47ft/sec), S= foil area projected vertically in sq.ft., CL = Coefficient of Lift(look up in Abbott and Doenhoffs "Theory of Wing Sections" or just use .6 for a quick idea).

From the book:

Lift is in proportion to:

1.-The area of the foil. Doubling the area doubles the lift.

2.-The Coefficient of Lift. Increasing the angle of attack to double the CL will double lift. Using a section with 105 greater CL increases lift 10%.

3.-The square of speed. Doubling speed increases lift by 4 times. Tripling increases lift by 8 times.

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Good catch! If speed was 2 and you double it=4; 2^2=4; 4^2=16 so lift increases 4 times. But if speed =2 and you triple it-6; 2^2=4 and 6^2=36 so lift increases 9 times, not 8-amazing that got by Ray. I guess the moral is never assume that just because its in a book its right.......

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Good catch! If speed was 2 and you double it=4; 2^2=4; 4^2=16 so lift increases 4 times. But if speed =2 and you triple it-6; 2^2=4 and 6^2=36 so lift increases 9 times, not 8-amazing that got by Ray. I guess the moral is never assume that just because its in a book its right.......

 

 

What is really amazing is that there are some folks on this thread who actually believe whatever you say. You are the prince of all things foily, right? You do pass yourself off as some sort of authority, right?

 

And you wonder why your boat needed to have a 20% extension to the ass end in order to float, much less foil. Now it doesn't foil as claimed and you still want to mythologize about your expertise and you can't even get the math correct? There really seems to be a problem in the math department that 50 years of experience never learned to get right.

 

Hilarious

 

Perhaps you should be submitting all your super complicated math problems to Hawk. He seems to have the right attitude about these things and does manage to maintain a meticulous desire to get the sums right. Folks who do airplanes tend to be decently meticulous about this stuff because if it doesn't work right, it falls out of the sky. You can get away with hobby horsing wheel stands that go nowhere... and then you call it foiling.

 

 

.

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Chris,

 

Good to see that you have developed an interest in math.

 

What scantling equations do you use for your multihull designs?

ostlinds interest in math is just a fake like everything else about him.The error he goes on about was not my error- it was an error made by Ray Vellinga in his book and caught by Hawk. He mouths off about me adding 20% to the length of the boat when I modified the hull to improve its light air performance capability-actually it was 8.6% ,yet he persists in another of a long list of lies and misrepresentations about me and my work. If I find I have made a mistake I will correct it-this is an experimental scale model- and I won't hesitate to fix anything that is wrong and do so publicly in the boatdesign thread.

"o" is a pathetic person with deep psychological problems who has lost his boat design business and makes sport of ranting against anything new -especially if it uses foils.

 

Go here for the facts about the mod to the main hull(post 1177), and read further on the mod to one of the ama foils and on the last page the newest video: http://www.boatdesign.net/forums/multihulls/high-performance-mpx-foil-self-righting-trimaran-test-model-36058-79.html

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Here is another funny Chris O spoof post...

 

 

Now, back to the topic at hand; intelligent,elegant and economical boat design!

 

pvc-pipe-canoo-2.jpg

 

Here is a prototype of a "skin on frame" canoe made from duct tape, PVC pipe and Hefty Bags. I call it the Garbaggio Special. Although any type of garbage bag would work, I have found through extensive testing and personal experience that Hefty bags make a superior canoe. Beaching is an important activity a boat should be able to endure. If you can't drag your boat hundreds of yards across the sand and gravel because it's too fragile, then it simply is a poor design - indeed it is. Indeed. This particular design also has several other striking features; it can be disassembled - for storage - or for transportation purposes. It also can be re assembled into a tent! Now how many other boat designs can boast such versatility! I dare say none, for I am a designer of intelligent design!

 

FJRACIPGP2DMIZY.LARGE.jpg

 

When I'm not using my PVC canoe for sailing and paddling expeditions to those beautiful secluded gunkholes in the deep, deep forest, I use my PVC canoe to pursue my other interests, like botany for example.

 

DSC_9287.JPG

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from bd.net:

 

For some damn reason there is a problem on youtube with the video-they say its in the que and will be processesed as soon as possible so I'm posting the pictures that tell the story and the "mov" version of the video. The boat was simply spectacular today. The wind was 3-5mph max but was 4-6 at my house from the south when we left. By the time we got to the Port it had switched to the SW and died to 3-5. But the waves left over from the 20 mile fetch south were still "bending around" thru the bridge. I would have preferred flat calm -no waves-just wind. But as it turned out-well, it could not have turned out better. First thing we noticed was that the lee ama popped up-it was then we knew this was going to be a great day. Shortly after the ama popped up the whole boat did and we got a couple of stretches of extremely stable, fast foiling. Perfect pitch stability, perfect ama foil altitude control-man, she couldn't have done any better. And all this in a 5MPH breeze! I couldn't be happier and more satisfied that the step by step analysis I did after the first three videos was right on target.

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Thanks. More testing and refinement of the i-flap and ama UptiP foil that worked so well today. It is 100% different than any current UptiP foil and the i-flap is perfect for lite air takeoff on a trimaran. It works like a wand controlled flap does on a t-foil-except it does it with no moving parts!

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nice!

huge mainsail... that sure is a light wind rig!

Getting this right on a radio conrolled boat is very difficult because you arn't actually sitting on it and feeling things happen. Thats a completley different story! The system needs to be very robust for a stable flight like that as there is no world class sailor on there pulling the strings. There is only one observer.

Looks great!

how big is this thing? 2 meters?

do you have an active control on the centerboard flap or a passive rod-system moth-style?

the rudder seems quite large, but still you problems tacking. I'm not sure how this all scales but on bigger boats this sure seems to work better!

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Well done Doug; it took a long time but it looks like its worth the wait- for the observers AND for you!


What will ChrisO, ZeroTheHero and others have to do with all their time now..?
Maybe they'll go out and do some sailing, or design a boat that someone ACTUALLY wants to buy?
I have to hand it to you; your resilience to their attacks over a prolonged period was admirable; many other grown men would probably have gone home and hung up their skates, but you stuck to your guns.


It looks like it did a couple of rapid wobbles when its up on the foils, was that due to the small wavelets, your controlling or something else unknown?

Anyway, well done. Next step, upsize!

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Thanks. More testing and refinement of the i-flap and ama UptiP foil that worked so well today. It is 100% different than any current UptiP foil and the i-flap is perfect for lite air takeoff on a trimaran. It works like a wand controlled flap does on a t-foil-except it does it with no moving parts!

 

no moving parts? how does that work?

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while watching the great video above

I have to say that this came into my mind:

Found this on another site.....

firearrowdive.jpg

 

with that huge mainsail I can Imagin that the behaviour in the picture above is the failure mode number 1.

I've build RC boats too, one of which a cat and this happens so easily. Even more than on any beach or racing cat.

Do the foils solve the problem?

I have no idea and I'm just that guy behind the computer, but from what I've seen I'd cut down the top of that mainsail by quite a bit. In the video the top third of the sail was not activa anyway. In 6 knots of breez.

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The hardest part in commenting on this video is attempting to recall all the things i thought would be problems.

 

It has been going on for YEARS, over and over, multiple threads constantly.

 

I think i questioned most the upwind viability and tacking, i think...maybe Doug or some one else can recall. Oh and price complexity on a full size boat, which i stand by as the main foil alone if scaled would be prohibitively expensive, that thing is massive and one rock strike away from epic failure.

 

More than anything the number one thing was to "stop fucking posting and just build the damn thing" which FINALLY seems to have happened! well kinda..

 

Still very, very early so Doug...try not to blow your load and stick to reality.

 

What i saw, it foiled - downwind - with a reasonably massive amount of water spraying up from the lee foil. In its current state that just doesn't look efficient, but once again -reality- it is early in an very complicated project involving multiple dynamic forces interacting in a natural environment. Making it this far is worthy of praise, really, keep at it. :D

 

But please ease up on the whole peoples foiler stuff, the Hobie trifoiler, a much simpler boat 20 years ago failed in the market at a price point far below what i would expect a "Fire Arrow" could possibly achieve, even at cost without labor. To be a revolution first you must show how this model is better than the models built in the 80s. :ph34r: as a benchmark i think the trifoiler was a $12K (?) boat in the early 90's so adjusted for inflation about $21k today. That is crazy hard benchmark to achieve, so just have fun with it.

 

 

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I've said some ten times now over the last four years of this gestation period that if it works as advertised, I'll be right at the front of the line offering congratulations for a successful effort. That still stands with no excuses to the contrary.

 

Step right up Chris.

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Congratulations Doug!

The new foil shape looks to have promise!

 

Dick Newick said he likes to spend 1/3 of his time designing, 1/3 of his time sailing and 1/3 of his time building. Don't forget to sail the boat and have some fun.

 

You are only a couple of iterations away from a kickstarter project! If some crazy bastard can start a kickstarter project for potato salad, you could start one for a foiling trimaran.

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It looks like this thread is about as dead as Doug's ideas and stupid attempt at an RC boat.

 

Now that Doug's development project is SA front page news... maybe in the furture you would consider not exposing you ignorance until after the results are in :)

 

Some will notice that in your "interests" that "thinking" was not included

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Thanks. More testing and refinement of the i-flap and ama UptiP foil that worked so well today. It is 100% different than any current UptiP foil and the i-flap is perfect for lite air takeoff on a trimaran. It works like a wand controlled flap does on a t-foil-except it does it with no moving parts!

no moving parts? how does that work?

 

 

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Aside from the whole boat foiling stably and fast in a 5 mph breeze, the big success yesterday was the ama foils.

The ama foil is quite experimental and is inspired by the TNZ UptiP foil but with some major differences. Each ama foil includes a molded in flap whose area will be reduced after more testing.(see sketch) The way it works is that the molded in, fixed flap acts to lift the ama early-even before the main hull and as it lifts the uptip portion(with the i-flap) breaches the surface reducing the high lift drag of the flap. In other words, the UptiP foil with the i-flap acts like a wand controlled t-foil except with no moving parts. In this first video the "solid state" ama foil had excellent, intrinsic, altitude control. Testing will improve this with lower wetted surface.

On the left(in the picture) ama foil I've outlined the area I think will be able to be removed as testing continues:

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Thanks, guys-it's great to have this thing working so well after such a long struggle. I appreciate the good wishes!

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Excellent Doug! Keep up the good work and fuck'em for those who have been beating so hard on you.

 

As an inventor you have to have faith in your creations, commitment in your design.

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Well, where does one start?

 

Congrats.... er, sort of.

 

I agree completely with Cavandish's assessment above:

 

 

"... It has been going on for YEARS, over and over, multiple threads constantly.

 

I think i questioned most the upwind viability and tacking, i think...maybe Doug or some one else can recall. Oh and price complexity on a full size boat, which i stand by as the main foil alone if scaled would be prohibitively expensive, that thing is massive and one rock strike away from epic failure.

 

More than anything the number one thing was to "stop fucking posting and just build the damn thing" which FINALLY seems to have happened! well kinda..

 

Still very, very early so Doug...try not to blow your load and stick to reality.

 

What i saw, it foiled - downwind - with a reasonably massive amount of water spraying up from the lee foil. In its current state that just doesn't look efficient, but once again -reality- it is early in an very complicated project involving multiple dynamic forces interacting in a natural environment.

 

But please ease up on the whole peoples foiler stuff, the Hobie trifoiler, a much simpler boat 20 years ago failed in the market at a price point far below what i would expect a "Fire Arrow" could possibly achieve, even at cost without labor. To be a revolution first you must show how this model is better than the models built in the 80s...."

 

 

 

Truth is, the boat still has not foiled stably for any controllable distance. It got its ass out of the water on a reach, but it can't do it upwind and in that reality, the telling eventuality of this ride will show itself. There are a million things that could be said, but they will wait as that collection of truths are not going to go away.

 

So, congrats.... er, sort of.

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.

...now what's in the plan? :mellow:

 

Thanks. More testing and refinement of the i-flap and ama UptiP foil that worked so well today. It is 100% different than any current UptiP foil and the i-flap is perfect for lite air takeoff on a trimaran. It works like a wand controlled flap does on a t-foil-except it does it with no moving parts!

.

...so a quick visit to the patent office?

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.

...now what's in the plan? :mellow:

Thanks. More testing and refinement of the i-flap and ama UptiP foil that worked so well today. It is 100% different than any current UptiP foil and the i-flap is perfect for lite air takeoff on a trimaran. It works like a wand controlled flap does on a t-foil-except it does it with no moving parts!

.

...so a quick visit to the patent office?

 

 

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

Probably not. I want it in the public domain to add to the rapidly growing body of knowledge about foiling. Anybody is welcome to use it or try it or whatever. You might say thanks if you do. I think it is an incredible variation on an UptiP foil.....

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That is really sweet! Congratulations on such an awesome build!

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

Thanks and thanks again to everybody for the good wishes(except one, I guess-hah!) And thanks to Scot for putting the Fire Arrow on the front page.

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since I don't recall seeing it: to scale, what would be the draft of the main foil?

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The exact scale up would mean a 5.7' draft off the foils. But you wouldn't scale this up exactly: a full size 19.5' version would have a max draft of 3.6 to 4'off the foils. Of course, the full size foils would be retractable.

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since I don't recall seeing it: to scale, what would be the draft of the main foil?

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

The exact scale up would mean a 5.7' draft off the foils. But you wouldn't scale this up exactly: a full size 19.5' version would have a max draft of 3.6 to 4'off the foils. Of course, the full size foils would be retractable.

.

...seems to me that mothies have more foildraft than that ,,no?

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Your foils look just as big as a moth. Interesting.

 

Is the idea of your design fully automatic attitude control? Or is there an adjustable flap on the forward main foil?

Yes. The flap is controlled by dual wands and is completely automatic. No adjustment of the rudder foil is required. The ama foils have designed in intrinsic ride height control requiring no adjustment.

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Well, where does one start?

 

Congrats.... er, sort of.

 

I agree completely with Cavandish's assessment above:

 

 

"... It has been going on for YEARS, over and over, multiple threads constantly.

 

I think i questioned most the upwind viability and tacking, i think...maybe Doug or some one else can recall. Oh and price complexity on a full size boat, which i stand by as the main foil alone if scaled would be prohibitively expensive, that thing is massive and one rock strike away from epic failure.

 

More than anything the number one thing was to "stop fucking posting and just build the damn thing" which FINALLY seems to have happened! well kinda..

 

Still very, very early so Doug...try not to blow your load and stick to reality.

 

What i saw, it foiled - downwind - with a reasonably massive amount of water spraying up from the lee foil. In its current state that just doesn't look efficient, but once again -reality- it is early in an very complicated project involving multiple dynamic forces interacting in a natural environment.

 

But please ease up on the whole peoples foiler stuff, the Hobie trifoiler, a much simpler boat 20 years ago failed in the market at a price point far below what i would expect a "Fire Arrow" could possibly achieve, even at cost without labor. To be a revolution first you must show how this model is better than the models built in the 80s...."

 

 

 

Truth is, the boat still has not foiled stably for any controllable distance. It got its ass out of the water on a reach, but it can't do it upwind and in that reality, the telling eventuality of this ride will show itself. There are a million things that could be said, but they will wait as that collection of truths are not going to go away.

 

So, congrats.... er, sort of.

 

 

So, eh, how many Chris O designs sort of made it to the front page?

Your level of congratulatory sincerity matches the relivance of your opinion as a "designer."

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The hardest part in commenting on this video is attempting to recall all the things i thought would be problems.

 

It has been going on for YEARS, over and over, multiple threads constantly. Nonsense.

 

I think i questioned most the upwind viability and tacking, i think...maybe Doug or some one else can recall. Oh and price complexity on a full size boat, which i stand by as the main foil alone if scaled would be prohibitively expensive, that thing is massive and one rock strike away from epic failure. Tacking in this video was a problem because I used the Dual Rate Function and Exponential functions of the radio to de-sensitized the rudder. In the other four videos the boat tacked perfectly as would a full size version. You say the main foil would be prohibitively expensive and I say that is just nonsense. A fullsize version of this boat would provide three or four people a fast foiler that would take off in a 5 mph breeze and yet they would sit on either side of the cockpit -not having to run side to side, or, for that matter even move. You can see in the model-there is no movable ballast yet the thing flies perfectly with the equivalent weight of three 175lb people and 26 pounds of drinks and sandwiches. Not only that but the same boat could be singlehanded with the owner siting in the same place-w/o having to move. It makes "easy to sail" really mean something in terms of a foiler.

 

More than anything the number one thing was to "stop fucking posting and just build the damn thing" which FINALLY seems to have happened! well kinda..Yeah, and what a chorus of bullshit that was!

 

Still very, very early so Doug...try not to blow your load and stick to reality. Are you kidding me? A new foiler configuration used for the first time in the history of mankind with a new version of an UptitP foil never before seen on the planet earth that worked perfectly and I'm not supposed to be excited? Right......

 

What i saw, it foiled - downwind - with a reasonably massive amount of water spraying up from the lee foil. In its current state that just doesn't look efficient, but once again -reality- it is early in an very complicated project involving multiple dynamic forces interacting in a natural environment. Making it this far is worthy of praise, really, keep at it. Thanks. So the spray when the boat is hauling ass in a 5 mph wind is a bad thing? Give me a break! The whole system is very efficient-any boat that foils in a 5 MPH breeze is pretty damned efficient! The boat lifted off several times on a close reach-once I get the main set right it will foil upwind-no ifs ands or buts. In fact once it's all dialed in I believe the thing will tack on foils.

 

But please ease up on the whole peoples foiler stuff, the Hobie trifoiler, a much simpler boat 20 years ago failed in the market at a price point far below what i would expect a "Fire Arrow" could possibly achieve, even at cost without labor. To be a revolution first you must show how this model is better than the models built in the 80s. :ph34r: as a benchmark i think the trifoiler was a $12K (?) boat in the early 90's so adjusted for inflation about $21k today. That is crazy hard benchmark to achieve, so just have fun with it. Perhaps you're confused: this boat does not ,in any way represent a "Peoples Foiler" but a boat using this technology could possibly become a Peoples Foiler. A 12' high performance version of this boat's technology could blow beachcats away and be relatively inexpensive easy to sail, easy to trailer etc.. The Peoples Foiler is not here yet and it remains a great concept for the not too distant future. In fact, I think AMAC is working on it now!

See the 12' version of this boat below-using planng ama's with or w/o foils:

 

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We are still awaiting your design largesse, Lummy. I know where mine resides... where is your original content?

I'm already content with the recognition that my design work has gained. I don't need an SA page splash to get there. Steady sales of boat plans will do that for a guy, Lummy. Well, that and having an everyday husband-wife crew pilot one of my designs to a Class 3 win in the Watertribe Everglades Challenge also does nice things for the interest level... and it's not even my working profession.

And relevance, Lummy, is spelled that-a-way.... and here I thought that a professional scientist would have long ago adopted Spell-Check within his OS. I'll need to regroup on that bit of cap tipping. Apparently there are still a whole pile of fools running around with a 80286 mentality for state-of-the-art tools. And you graduated from college with what degree in hand?

 

Doug's congratulation nod from me is commensurate with his accomplishment. Nothing more and nothing less. The boat foils... sort of... and he has received a "sort-of" congratulatory response to suit the reality. I guess in your world, an off wind only foiling boat is a success, and no notion of being able to do so upwind matters. I don't look at it that way and I suppose that is why you do not design boats and others do. Perhaps you'd like to expound on that tiny bit of messy objective thinking?

 

And further addressing the issue: even when the boat foiled off the wind, it only did so in fits and spurts, not level, steady flight for any controllable distance. Actually, the Rave had issues such as these and we all know how that performed as a successful product. It's incredible, actually, that Doug piddled around for four years and this is the fitful result, while Michele Petrucci developed and presented a fully functional foiling cat in less than half that time... at full size!... and the boat is ready to be presented to the buying public. Put in perspective, with that metric as an indication of success... and you have your answer.

 

.

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Congrats Doug! Cool to see it out and flying! I had no idea how big the beast is, wow. Not something you toss in the back seat and head to the local pond with!

 

Whilst looking for a picture of Phil Morrison's foiler, as your ama foils reminded me of this (this is a semi planing foil right?):

 

29837d1236333811-tomahawk-peoples-foiler

 

I ran across this RC mono foiler, looks to be a canter also!

 

 

 

Anyway... Is the "i-flap" under the ama foil a step? The tomahawk foil has steps on the top.

 

Now that you've got the foils more dialed in, you really need to deal with the rig and main. Looks like there's zero leech tension which could be what's impeding its tacking. Is the jib already on port but the top of the main is still on starboard? It's clearly apparent how the top of the main is hurting you in the jibes. Even as a light air rig, probably best the main visit the loft floor for some trimming and tightening! Saw some headstay wobbles too.

 

Get the power under control and you're blazing!

 

 

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I think posting this on the front page has more to do with the shit storm Doug's threads produce ie traffic.

 

Doug, congratulations on getting the model to lift. I appreciate your dogged perseverance, your tireless advocacy of foiling and the pride you put into your work.

 

But I have to admit, I'm still stumped. Given the simplicity and effortlessness by which the above tri foils, tacks and gybes and the success you and your Dr friend had many years ago with foiling tri's, where does this current project fit in? Is it supposed to be an improvement on the above technology? What do you hope to archive in the end? Is there an end?

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I think posting this on the front page has more to do with the shit storm Doug's threads produce ie traffic.

 

Doug, congratulations on getting the model to lift. I appreciate your dogged perseverance, your tireless advocacy of foiling and the pride you put into your work.

 

But I have to admit, I'm still stumped. Given the simplicity and effortlessness by which the above tri foils, tacks and gybes and the success you and your Dr friend had many years ago with foiling tri's, where does this current project fit in? Is it supposed to be an improvement on the above technology? What do you hope to archive in the end? Is there an end?

See the boat design thread, linked above. In its simplest form this model is a technology demonstrator. It shows that an oversquare platform can be made to work on small tri's not just the 60' Hydroptere. It will demonstrate the viability of this concept for foilers 20' and under(maybe larger as well) and it will demonstrate that movable ballast is not a requirement for a small sport trimaran foiler-and that this concept will result in an extremely comfortable easy to sail boat. It demonstrates a fully automatic foil system requiring no rudder foil adjustment and automatic altitude control on a "solid state" ama foil the likes of which has never been seen. I hope it can inspire people with the underused trimaran platform and show that cats aren't the only very fast boats under 20'. And above all FUN! This concept can lead to unique small trimarans that offer much more than any small cat or tri does now........

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I must not have been around here long enough or something. Why is there so much derision? I admit to being underwhelmed by Doug's Tantra but these model hydrofoils and stuff are pretty cool. Let's see how many armchair sailors (Chris O?) can get into the workshop and make something and show their faces on SA.

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Let's see how many armchair sailors can get into the workshop and make something and show their feces on SA.

 

 

.

....I can hardly wait for the youtube with a crew of 5 squirrels :mellow:

we work our way up to squirrels up from mice & chipmunks. Squirrels are Fire Arrow v.4.0

.

....pro-crew at the ready.....

 

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Re: Names... Doug, there are no "solid-state flaps"... that´s like saying your boat is a "monohull with two middle channels"...

 

what you did is just a wing twist with different profiles inboard and outboard, which is actually what most airplane wings are done. A flap is a moving surface...

 

anyway CONGRATS on the boat, keep going, very interesting

 

 

hey doug, you gonna call your version of the up-tip the down-tip?

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We are still awaiting your design largesse, Lummy. I know where mine resides... where is your original content?

 

I'm already content with the recognition that my design work has gained. I don't need an SA page splash to get there. Steady sales of boat plans will do that for a guy, Lummy. Well, that and having an everyday husband-wife crew pilot one of my designs to a Class 3 win in the Watertribe Everglades Challenge also does nice things for the interest level... and it's not even my working profession.

 

And relevance, Lummy, is spelled that-a-way.... and here I thought that a professional scientist would have long ago adopted Spell-Check within his OS. I'll need to regroup on that bit of cap tipping. Apparently there are still a whole pile of fools running around with a 80286 mentality for state-of-the-art tools. And you graduated from college with what degree in hand?

 

Doug's congratulation nod from me is commensurate with his accomplishment. Nothing more and nothing less. The boat foils... sort of... and he has received a "sort-of" congratulatory response to suit the reality. I guess in your world, an off wind only foiling boat is a success, and no notion of being able to do so upwind matters. I don't look at it that way and I suppose that is why you do not design boats and others do. Perhaps you'd like to expound on that tiny bit of messy objective thinking?

 

And further addressing the issue: even when the boat foiled off the wind, it only did so in fits and spurts, not level, steady flight for any controllable distance. Actually, the Rave had issues such as these and we all know how that performed as a successful product. It's incredible, actually, that Doug piddled around for four years and this is the fitful result, while Michele Petrucci developed and presented a fully functional foiling cat in less than half that time... at full size!... and the boat is ready to be presented to the buying public. Put in perspective, with that metric as an indication of success... and you have your answer.

 

.

 

It's good that you don't place emphasis on the recognition of your designs. It doesn't really matter how much you suck at your hobby, as long as you enjoy it, right? Hopefully, posting your sage advice on the forums 24/7 doesn't get in the way of all of your handyman jobs.

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Re: Names... Doug, there are no "solid-state flaps"... that´s like saying your boat is a "monohull with two middle channels"...

 

what you did is just a wing twist with different profiles inboard and outboard, which is actually what most airplane wings are done. A flap is a moving surface...

 

anyway CONGRATS on the boat, keep going, very interesting

 

 

hey doug, you gonna call your version of the up-tip the down-tip?

 

 

Wrong(in my humble opinion). The i-flap is a "solid state" flap because it works just like a flap- only one that has been glued in position. I got the idea when trying to think of a way to have the UptiP foil work like the mainfoil does (at low speed and with little leeway): high lift for take off then neutral flap and lift due to the angle of incidence of the foil and resulting angle of attack-probably as well as leeway coupling when there is enough leeway. It looks like a flap, works like a flap ,so it must be a flap? Regardless what you might want to call it it works well and as we* refine it ,it will only get better. The results of the fact that it works are: high lift for takeoff then lift from the non high lift portion of the foil. It's pretty cool really, and a solid part of what makes the Fire Arrow go.

*Team Fire Arrow

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C

 

 

 

Congrats Doug! Cool to see it out and flying! I had no idea how big the beast is, wow. Not something you toss in the back seat and head to the local pond with!

 

Whilst looking for a picture of Phil Morrison's foiler, as your ama foils reminded me of this (this is a semi planing foil right?):

 

I ran across this RC mono foiler, looks to be a canter also!

 

Anyway... Is the "i-flap" under the ama foil a step? The tomahawk foil has steps on the top.

 

Now that you've got the foils more dialed in, you really need to deal with the rig and main. Looks like there's zero leech tension which could be what's impeding its tacking. Is the jib already on port but the top of the main is still on starboard? It's clearly apparent how the top of the main is hurting you in the jibes. Even as a light air rig, probably best the main visit the loft floor for some trimming and tightening! Saw some headstay wobbles too.

 

Get the power under control and you're blazing!

Hey "Liquid"! You're right 100%- the main is pissing me off-it's fully adjustable but I get out in the inferno, thinking about getting the thing to foil and I forget about the damn sail. This time we* almost took off with the "peak halyard" loose! I had to get Dan to help turn the thing sideways in the water so I could adjust it, the downhaul and the vang. It wasn't easy to hold it like that so my excuse is that I have no excuse but just a rush. Now that I know the thing works so well there won't be so much pressure next time and I might actually read my checklist. It's a real bitch to assemble and take this thing apart each time-I need a trailer so I can carry it assembled, but that won't happen for a long time.

As to the UptiP ama foils and the i-flap: it's as if you took a normal foil and glued a flap in place-that is ,in essence, exactly what I did. Remarkable how well it worked first time out. From the first time I saw the TNZ foil I absolutely marveled how they could make a foil-a single foil- control the altitude for the whole boat. I had the quicky molds already made for using "C" foils on this thing and as soon as I thought I understood how the UptiP foil worked I thru all that away. The first version didn't have enough area and AOI for low speed take off so after a week of wracking my brain for an answer I came up with these.

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nit picking - but if I understand it right, I wouldn't call it a flap. In the traditional sense, a flap is a mechanism whereby a wing can change it's lift profile by moving a surface.

 

If I understand it correctly, what you did was add more lift near the root of the foil by making the chord longer?

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>

Re: Names... Doug, there are no "solid-state flaps"... that´s like saying your boat is a "monohull with two middle channels"...

 

what you did is just a wing twist with different profiles inboard and outboard, which is actually what most airplane wings are done. A flap is a moving surface...

 

anyway CONGRATS on the boat, keep going, very interesting

 

 

hey doug, you gonna call your version of the up-tip the down-tip?

 

 

Wrong(in my humble opinion). The i-flap is a "solid state" flap because it works just like a flap- only one that has been glued in position. I got the idea when trying to think of a way to have the UptiP foil work like the mainfoil does (at low speed and with little leeway): high lift for take off then neutral flap and lift due to the angle of incidence of the foil and resulting angle of attack-probably as well as leeway coupling when there is enough leeway. It looks like a flap, works like a flap ,so it must be a flap? Regardless what you might want to call it it works well and as we* refine it ,it will only get better. The results of the fact that it works are: high lift for takeoff then lift from the non high lift portion of the foil. It's pretty cool really, and a solid part of what makes the Fire Arrow go.

*Team Fire Arrow

 

 

Don´t get me wrong, I see clearly the intent and it should work as you said.

 

"I" don´t want to call it anything. There are accepted terms already. So, just for the sake of clarity: a flap -movable surface- transforms a low camber profile in a higher camber profile. If you glue the flap in the "low" position... you end up with a high camber profile, nothing else, that´s what your outboard foil is.

 

but again, names is not the important part, you making an interesting boat is, so good luck

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Thanks. There is another difference compared to any airfoil I could find: the resulting shape of the foil is way different than even early thin airfoils because the thickest portion of a line drawn from the leading edge to the bottom of the "flap" is way aft compared to a normal airfoil. But no matter-it works and I'll go from there.

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That's a heck of a lot more foiling than the one or two seconds I wanted to see! I've got a smile a mile wide just from looking at that video, so I can't imagine how good you must feel. Long way to go yet, of course, but it's only going to get better. And yes, it doesn't look like the people's foiler, but you could be creating the perfect boat for disabled sailors who want to be part of the foiling revolution, and I don't see why they should be left out of the fun. Looking forward to seeing it foiling upwind.

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Yes, it foiled so I have to praise Doug for that (finally, after how many at BoatDesign.net thousand upon thousands of nutty posts?) ... but still the "Bird of fire" thing is r e a l s l o w.

Because of the flotilla of foils and drag it carries.

I think a basic mono keel boat design of simialr size would beat it.

And will be waiting to see how Bird of fire handles more wind because it is crazily overpowered and tip trucky with the rig design it carries at the moment.

This is just a whisper as an anti-dote to the no clothes Lord/King.

Because the real performer (and a simple basic foiler) posted by Southern Cross, in high winds, really reveals how a purist and clean design can perform; no bells, whistles or paddle weirdness or complexity.

Remember what Dick Newick said about stupidity.

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Yes, it foiled so I have to praise Doug for that (finally, after how many at BoatDesign.net thousand upon thousands of nutty posts?) ... but still the "Bird of fire" thing is r e a l s l o w.

Because of the flotilla of foils and drag it carries.

I think a basic mono keel boat design of simialr size would beat it.

And will be waiting to see how Bird of fire handles more wind because it is crazily overpowered and tip trucky with the rig design it carries at the moment.

This is just a whisper as an anti-dote to the no clothes Lord/King.

Because the real performer (and a simple basic foiler) posted by Southern Cross, in high winds, really reveals how a purist and clean design can perform; no bells, whistles or paddle weirdness or complexity.

Remember what Dick Newick said about stupidity.

What an asinine comment. Twice wind speed is not slow. The boat has only three foils in the water when foiling-no more than any modern foiler-and one of them is unloaded the faster the boat goes. It foils in a 5 mph breeze -like my last production RC foiler did.

What has happened to you?

post-30-0-23598900-1406334140_thumb.jpg

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Umm...he got an RC boat up on foils with a novel launch system - the fixed 'flap' that lifts both the boat and itself out of the water, and kind of replaces the wand when the hulls start to drop.

Pretty clever, if you ask me.

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Doug, just watched the vid and it looks good. You got it to fly and my hat is off to you for that. I never thought you would so I am eating some crow right now. I'll give you credit where it's due. I'll say this though, no where in the net has so much hype been made by a designer. Hundreds of pages! But here we are, it works. Now, you need to fix the sail plan, it looks terrible. A better sail plan will mean better foiling. That would mean better performance, which is exactly what you want. This is only version 2/3 of this design so I think you will work it out.

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Hi Doug,

Congratulations from me as well!

 

Great to see your boat in stable foiling mode! And those ama foils are really sharp looking weapons.

 

Thanks guys!

 

Doug, just watched the vid and it looks good. You got it to fly and my hat is off to you for that. I never thought you would so I am eating some crow right now. I'll give you credit where it's due.

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Here is the long version of the video. There are a couple of instances where the boat begins to foil upwind, one about 2 min in. I can't get over that ridiculously twisted main-robbing a lot of power! Hopefully, I'll get the hang of setting it right before too damn long.

 

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nit picking - but if I understand it right, I wouldn't call it a flap. In the traditional sense, a flap is a mechanism whereby a wing can change it's lift profile by moving a surface.

 

If I understand it correctly, what you did was add more lift near the root of the foil by making the chord longer?

 

What I did was glued on a piece of balsa at a 15 degree angle to serve as a sacrificial mold then carbonated it with 5.7oz woven material. The extra area was from the radius between the daggerboard portion and the angled up lifting portion to the tip. The tip is twisted the exact opposite way it would be if the foil had washout-in other words the angle of incidence of the foil increases from the radius to the tip. The idea will be to trim away as much of the high lift area as possible and still have high lift at take-off and have as much of the high lift area as possible disappear when the tip breaches the surface. So when its right there will be high lift at take off which goes away the faster the boat goes. Which is exactly what happens with the wand controlled main foil but the ama foils require no moving parts. The testing will allow us to get the right combination of high lift/ low wetted surface lift throughout the speed range. I know we can trim it some already because the photo below shows the tip poking thru in this 5 mph breeze. Both ama foils exhibited the characteristic proven by TNZ: the single UptiP foil can control altitude as both did here so well. If a choice has to be made between top end speed and low wind speed take off the low wind speed take off will win every time. If the full size version is ever produced it would also takeoff in a 5 mph breeze because I consider that critical for marketing a foiler in the US where the sailing winds are under 10 knots in many places much of the time. So in order to coerce someone to buy a thing like this they have to know that they will be foiling most of the time.......

 

In the picture below, the port ama foil is marked where I think the high lift area will be trimmed:

post-30-0-50637800-1406382301_thumb.jpg

post-30-0-94719600-1406382342_thumb.jpg

post-30-0-59739600-1406382390_thumb.jpg

post-30-0-09005700-1406382487_thumb.jpg

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This goes with my previous post. The pictures show the ama flight waterline just after its earliest takeoff, at high speed(like the picture shows in the last post) and the twist in the shape due to the i-flap. At the high speed waterline you can see how much of the high lift i-flap area can emerge from the water:


 

post-30-0-77987000-1406384960_thumb.jpg

post-30-0-09306200-1406384975_thumb.jpg

post-30-0-69677800-1406384984_thumb.jpg

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The testing will allow us to get the right combination of high lift/ low wetted surface lift throughout the speed range. I know we can trim it some already because the photo below shows the tip poking thru in this 5 mph breeze.

Congratulations Doug, it looks like your are off to a good start!

 

A couple of quick comments/questions......

 

1. It is very odd that you continue to use the term "us", and "we" when describing the work you are doing alone. What is the purpose???

 

2. Between your last 2 sails, you increased the area of your main foils by 53% (rudder), and 60% (main foil) respectively. Additionally, you increased the area of your J foils significantly. These are pretty significant changes. To what do you attribute these miscalculations?

 

3. I find it odd (and disingenuous) that you take screen shots of carefully chosen, single moments in time, and offer them as conclusive proof. As I said in my opening comment, I think you are off to a good start, but there is a lot more work to be done, and video to present, before you can validate the functionality of your concepts. Example: When comparing the picture above, with the J-Foil breaching the surface, and comparing it to the video, judging by the amount of spray and wake being generated, it appears that bottom of the foil is acting more as a planning (sp?) surface, than a functional foil.

 

4. Moving forward, while your varying-chord J foil tip foil may look good on paper, the fact is that boats do not sail in ice-rink smooth surfaces Therefore, the problem that you are going to encounter (and have to overcome) with this type of foil will be the ventilation that will be induced as the speed increases. If the low speed portion in brought back into contact with the water at speed (from things like waves, wakes, pitching, puffs, etc.) the large area tips are going to induce significant ventilation bubbles that will be sucked down the low pressure surface of the foil. This is why all the current J-Foils have such small surface piercing tips!!!

 

Again Doug, GREAT work, but please try to be a bit careful (humble?) with your assessments. It truly does take away from the your credibility, and therefore any earned respect.

 

Best Regards,

 

~Robert Thompson

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The testing will allow us to get the right combination of high lift/ low wetted surface lift throughout the speed range. I know we can trim it some already because the photo below shows the tip poking thru in this 5 mph breeze.

Congratulations Doug, it looks like your are off to a good start!*

 

A couple of quick comments/questions......

 

1. It is very odd that you continue to use the term "us", and "we" when describing the work you are doing alone. What is the purpose??? "US" is because it has been Dan and me doing the video and pictures and several close friends, who are experts in this field, consulting with me regarding the pictures and video. I did all the original design alone and most of the building alone except for sails, cross tubes and mast. So it is "US"!

 

2. Between your last 2 sails, you increased the area of your main foils by 53% (rudder), and 60% (main foil) respectively. Additionally, you increased the area of your J foils significantly. These are pretty significant changes. To what do you attribute these miscalculations? I was attempting to start out with the lowest wetted surface possible-we knew the foils would work at the right speed but, as I've said all along, early take off is most important-it trumps everything. So I decided to just flat out modify the main and rudder foil to have the exact same foil loading as my F3 14 years ago-which we knew would take off early. I thought I could jump ahead a step and I was wrong. But I got it perfect now for light air take off both on the main foils and ama foils. I'll try something and if it doesn't work the way I want it-I'll fix it-which I did. Now "we" will discuss how to go about refining it starting with the rig and getting the main right.

 

3. I find it odd (and disingenuous) that you take screen shots of carefully chosen, single moments in time, and offer them as conclusive proof. As I said in my opening comment, I think you are off to a good start, but there is a lot more work to be done, and video to present, before you can validate the functionality of your concepts. Example: When comparing the picture above, with the J-Foil breaching the surface, and comparing it to the video, judging by the amount of spray and wake being generated, it appears that bottom of the foil is acting more as a planning (sp?) surface, than a functional foil. Suggesting that showing a picture that was randomly taken and accidentally discovered was part of a disingenuous plot is complete bullshit!! You've got your alphabet wrong: if you were to reduce this foil to a letter or two it would be an modified "L"-with an i-flap"not a "J". You can look at the long video and other pictures posted on bd and see several instances of the ama flying before the main hull and automatically maintaining its altitude with no tip exposed. Not only that but as the main hull flys the ama altitude stays about the same until the boat speeds up. The foil worked exceptionally well and as I've said earlier "we " will refine it along the lines I've already described in detail in a previous post. And even if it was planing(which it wasn't) I wouldn't give a damn as long as it maintained altitude-as Hugh Welbourn says talking about DSS foils: "Whats wrong with planing" or words to that effect.

 

4. Moving forward, while your varying-chord J foil tip foil may look good on paper, the fact is that boats do not sail in ice-rink smooth surfaces Therefore, the problem that you are going to encounter (and have to overcome) with this type of foil will be the ventilation that will be induced as the speed increases. If the low speed portion in brought back into contact with the water at speed (from things like waves, wakes, pitching, puffs, etc.) the large area tips are going to induce significant ventilation bubbles that will be sucked down the low pressure surface of the foil. This is why all the current J-Foils have such small surface piercing tips!!! I disagree emphatically. Again it is NOT a "J" foil....

 

Again Doug, GREAT work*, but please try to be a bit careful (humble?) with your assessments. It truly does take away from the your credibility, and therefore any earned respect. If you think I'm not humble when I express my exceptional satisfaction in having solved a complex problem and made it work-you may be right(I don't think you are) but it's only temporary. However, I've taken a lot of shit from ignorant assholes for a long time so maybe you can forgive me. If you think I'm not humble because I try to explain what I/we think is going on and why, then I think you are just way off base. I believe in this project, in the concept and in the i-flap which I was lucky enough to come up with completely accidentally-I will continue to refine it with a little help from my friends after I take a few days off to savor whats happened-and understand whats happened. Thanks for your comments!

 

* Thanks!

Best Regards,

 

~Robert Thompson

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The testing will allow us to get the right combination of high lift/ low wetted surface lift throughout the speed range. I know we can trim it some already because the photo below shows the tip poking thru in this 5 mph breeze.

 

 

When comparing the picture above, with the J-Foil breaching the surface, and comparing it to the video, judging by the amount of spray and wake being generated, it appears that bottom of the foil is acting more as a planning (sp?) surface, than a functional foil.

 

I made reference to a planning foil above in post 1055... I got nothing back. Seems to me the added flaps make the foil go straight to the surface, thus planning...

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If the full size version is ever produced it would also takeoff in a 5 mph breeze because I consider that critical for marketing a foiler in the US where the sailing winds are under 10 knots in many places much of the time. So in order to coerce someone to buy a thing like this they have to know that they will be foiling most of the time.......

Doug,

 

Not the word I would have chosen!!!.......

 

Coerce:

1. To compel by force, intimidation, or authority, especially without regard for individual desire orvolition.

2. To bring about through use of force of other forms of compulsion.

3. To dominate of control, especially by exploiting fear, anxiety, etc.

 

 

Freudian slip perhaps??? ;)

 

Best Regards,

 

-Robert Thompson

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Re: Names... Doug, there are no "solid-state flaps"... that´s like saying your boat is a "monohull with two middle channels"...

 

what you did is just a wing twist with different profiles inboard and outboard, which is actually what most airplane wings are done. A flap is a moving surface...

 

anyway CONGRATS on the boat, keep going, very interesting

 

 

hey doug, you gonna call your version of the up-tip the down-tip?

 

 

 

I took this picture just for you. It shows a 63412 section with a 15 degree flap, only the flap is attached permanently and is therefore an intrinsic part of the foil and that's why its an "i-flap":

 

picture of the bottom side of the port UptiP/i-flap ama foil--

post-30-0-15505200-1406396271_thumb.jpg

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If the full size version is ever produced it would also takeoff in a 5 mph breeze because I consider that critical for marketing a foiler in the US where the sailing winds are under 10 knots in many places much of the time. So in order to coerce someone to buy a thing like this they have to know that they will be foiling most of the time.......

Doug,

 

Not the word I would have chosen!!!.......

 

Coerce:

1. To compel by force, intimidation, or authority, especially without regard for individual desire orvolition.

2. To bring about through use of force of other forms of compulsion.

3. To dominate of control, especially by exploiting fear, anxiety, etc.

 

 

Freudian slip perhaps??? ;)

 

Best Regards,

 

-Robert Thompson

 

Haven't you run into a boat salesman??

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