I am not that bothered why you said that, so don’t expect to hear anymore on criticism toward the thread from me…
The last time I checked… Air still has the same specific properties…
Yes this stuff we have to go on is old, but that isn’t the point here
“stone age” or not, you have to start somewhere.
If you have a folder with the latest in wing design on a mono, bring it on.
These things have been tried before, no one is saying they are a pioneer in the field.
Between us we have collated quite a good amount of data, from a time that had never heard of the internet…
Quite frankly - Information did not grow on trees back then, neither did wind tunnels, clusters, CFG, etc, etc, etc,etc.
This info is a legacy, we need to take it to the next level… Otherwise the trials (perhaps) predating our births were in vein. This is all in the learning curve…
‘Repeating experiments, expecting a different result’ is Albert’s 1st take on insanity…
Assumption is the mother of all ****ups… Boatbuilders 1st take on ‘cocky’ know it alls…
Knowledge is empowering, especially that gained from experience, why would you want to repeat someone else’s experiments if they took the time and trouble to accurately document their findings…?
Just a thought that wanted to share…
The latest wing for the AC 45 is a ‘simplified’ version of the wing on USA 17… Got me thinking…
Until someone puts a scaled multi element wing design against a simpler single wing design or similar we do not really understand the real term benefits.
Scaling a full sized design is not the sure-fire way to success either…
From experience building rc sailplanes I can tell you that scaling down a high performance sailplane to an rc version keeping certain parameters scale like, affects performance and at some point it can be un flyable! Reynolds numbers vary considerably and diferent airfoils have to go in place to maintain close to similar flying caracteristics. Sometimes tail area and stabilizer area have to be increased to obtain better stability or flyability. BUT scaling down gives you a good starting point or something to work with.
On the other hand, we CAN go from model concept and scale up to full size. Many of the airplanes we know that have made history have gone through this process. One of the most current ones (or at least a few years old) is the Ultimate 10-300. It first was concived as a rc model and went into full concept form there.
If you guys are looking for theory and science, please visit this webpage. Many of the concepts explained here can be aplyied to the Wing sail concept. NASA
Anyway, in my case, it would be a 20% investigation and 80% TLAR My theory says: high aspect ration = higher speeds.
I hope this helps to get back on track about Wingsail Monohulls!
Enrico
Lets name the problem we have here:
Just imagine walking or running up the staircase.
a)If you simply take one step after the other - you´re on the safe side but rather slow.
b) Going faster, you still can be safe and under complete control when taking two steps at a time throughout the whole staircase.
c) Coming in really fast, you could take the first four or five steps with a jump, but then you need to slow down -
and probably can carry on with two steps at a time.
d) Trying to take - lets say - all ten or twelfe steps at once with a huge jump and you may end up bleeding without any teeth left in your mouth -…-
Thats just an imaginable example for our problem.
Actually I´m talking about the huge amount of knowledge, experience and (proofen) datas regarding wingsails collected over the decades.
If you want to learn and understand all of it, it will take you several years and a master degree on aerodynamics.
Trying to achieve all of it in one big sweep, you may end up - no, not with broken teeth - but possibly/probably at least with a broken wing.
Conclusion:
In order NOT to need several years, unfortunately you GOT TO leave out several steps while moving ahead.
The only question here is, WHICH steps you can leave out safely.
Furthermore:
Who´s advise or what advise you can trust (to keep your teeth).
So it simply could be “helpful” to question the source of informations.
I´m just a simple 50 year old retired shipwright with 33 years of boat - and yacht-building experience.
(I started my apprenticeship at 17.)
I´m aware of the steps I had to leave out over the years.
Some of them have been a pain for me - or still are.
And lots of so-called “good advise” from so-called “experts” leaded me to dead ends -
where I had to go back and start again from the beginning.
Loosing lots of time, money and energy -…- got me?
So I´m really seriously concerned if I ask:
“Can you TRUST those sources
or - can you trust those informations?”
“Or - are these datas up-to-date?”
So - please don´t call me picky.
I just don´t want to see you (or anybody) bleeding in any way.
And as a conclusion of all the datas I currently have,
I decided to build a 2 meter rc-model of the 45ft. AC training catamaran
with a 2.8m high solid wing according to the rules of the 2M multihul class.
I wouldn´t invest my time in a monohulled keelboat with a wingmast.
Not true anymore. With advances with computers and their programs, it’s not has hard for the “layman” to pickup and experiment. Without having to build anything. Simulations go a long way, even with low Reynolds numbers. Dr. Mark Drela from MIT has advanced the field tremendously (he is one of the authoritative researchers in low Reynolds numbers) as he written XFOIL (text output) for the simulations of airfoils in low Reynolds numbers, which has been updated with XFLR (graphical output). Heck, even I have used XFLR with good results, following online tutorials.
Again, things have changed since you started out. Newer materials, newer construction techniques, newer data have been found in 50 years.
Personally I don’t think it’s even worth 5 cents with an attitude as yours. As I’ve said before with sediments as yours, we would still be living in caves and saying fire is a stupid idea, and beating each others heads with rocks.
So why don’t you take a break and let those who want to try expand mans knowledge and at least experiment. Who knows, someone might have a spark of an idea that others haven’t come up with and find a solution to this idea. Or it might turn out that you’re right and you would be exonerated. Who knows!?!?!?
How about more building, less flaming here… There is no question that wing sails can be very efficient on mutihulls, land yachts, and ice yachts… The question is can they be made to work well on monohulls… well enough to beat the same class monohull with soft sails consistently… or at all…
I say time to put your money where your mouth is… and that is NOT intended as a slam in any way… I’ll be the first to congratulate you once you prove what can be done…
Disabled, you’re obviously fairly passionate about boats but you do seem yo have a problem with your posting style. On a good day your posts sound condescending and on a bad day they can sound truly obnoxious. I can’t believe that is your intention, but you’d probably find people would give more consideration to your ideas if you could post in a less controversial style.
It is fairly simple to disagree without appearing rude. It is a problem of written communication, where only words and the occasional smilie can give an idea of the poster’s “tone of voice”.
Hey guys - as moderator, I received a complaint from a registered user who suggested some posts were becoming “polemic and rude” (his quote) so can we move to “civil” discussion please? There are no issues with disagreement of facts and posting of opinions - and answering questions related to the opinions and facts, but be careful you don’t step over the line and start making posts too personal or appearing to others to be rude.
Thanks, Dick Lemke
One of the forum Moderators
ADDED: Ernst - the color changes in last post are examples of what causes others to dislike some of your posts…even with the “smilies” added. They have nothing to do with wingsails on monohull boats, and not sure why they are there, other than to continue to “stir the pot”. Wanted to post as an example of rhetoric that we don’t need.
Not true unless it has two wings and it also can fly! :lol:
Anyway, I was sitting in front of my workbench last night, thinking how to make a wing. I scrambled and old airfoiled shaped stab from a wrecked sailplane and started fiddling with it, just to get a better look at how the mechanics would work. Well … after 45 min of getting no where I was back to square one. So I decided to take some 1 mm balsa and 1 mm carbon fiber strip and play around trying to get a symetrical foil. Well that went well, it looked so nice and stiff, I decided i would use it for my round ranger keel … Again, leading no where, got figured out the wing shape and the length and structure, but the real question is as of the mechanics, how to actuate the flap, what kind of support structure would the flap need, and how should the main wing behave versus the flap, should it be offset or should it be that both wing and flap rotate.
questions question … back to building board!:rolleyes:
Enrico
Hi Dick Lemke,
Wasn´t THAT the one which was polemic and rude?
It wasn´t my intention to go down that road at all,
but this “gent” seems to take himself a “bit” too serious -
so I just decided to make a little fun of him.
Quote from page 3:
“Habe jetzt die Profile die beim C-Cat eingesetzt werden.
Das vordere Profil ist ein S901F 50% (nicht in Profili2 enthalten) muß beschafft werden
das hintere (FLAP) ist ein NACA 0012 50%”
Translation for the lazy guys:
“Now I have the profiles used for the C-Cat.
The forward profile is a S901F 50% (not included in Profili2) need to get that
The aftward (flap) is a NACA 0012 50%”
Then on page 4:
“Der Mast ist ein NACA0020. Flap ist ein NACA0012.
Muß alles noch mit Reynold´s gechecked werden…”
Translation:
" The mast is a NACA0020. Flap is a NACA0012.
It all still needs to be checked with Reynold´s…"
Ernst - just to clarify a possible misconception … complaint didn’t come from “Guzz” and the colors/example simply happened to be on the first page opened that I hadn’t viewed yet. This recent post is most informational for anyone looking for comment, theory and actual testing - whether the wing is for a monohull - or the “other type” of craft.
Here´s some more information for the Reynold´s fans:
Quote from the same thread on page 7:
“Die Profildicke ist entsprechend dem Reynoldsbereich von 40.000 bis 500.000 passend. Flapstellung zw. 2 bis 20<° wirken sich tierisch auf den Ca und Cw-Wert aus… je nach Re-Zahl 60 mm Profildicke bei 600 mm Profillänge…(10%) …ist das noch zu dick?”
"Für flachere Profile sind unsere Modelle nicht schnell genug…da sie in Öl fahren "
Do you need translation?
This is for a Mini40 Trimaran of 48" length.
50" Marbleheads are not faster.
More infos.
This solid wing of 0.9m2 is 180cm high.
Expected/calculated weight 420-500 gr.
Disabled:
Thank you so much for posting those links, that was the answers I was looking for!!!
Hey Guys,
I think the wing structure needs to be a bit simplified to allow twist to build in to it by wind power. Its a crazy Idea but I think it would work. About control with a single servo I was thinking maybe use the same sheet line to control the flap and keep the end tight to the main wing. That way the whole system works in one single control, release the sheet and wing and flap open but at the same time the main wing gets loose and opens more than the flap, thus allowing control of the gap in between wing and flap. Please if I’m thinking outloud nonsense, I will be ok if stand corrected. Any ideas?
Back to the wing project. I think I’ll try a small Footy size just to get an idea of how it works and sort it out before jumping onto bigger size and higher $$ materials.
Not quite sure what you mean by “allow twist to build in to it by wind power”… If you’ve ever twisted a sailplane wing you will realize that the covering quickly takes on big wrinkles as it tries to stretch when the wing twists… If you are talking about arranging the flaps to progressively allow the trailing edge to fall off, that is a different matter… The trouble there is that as you allow the upper panels to fall off, you get less camber as well… I would think that either solution is less than desireable…
Hey Enrico,
for any boat- and wingsize you choose -
build a simplyfied model first!
There is no need to build the complex wing from the picture in the first place.
To get the idea of what could be going on with your wing,
you just need three ribs of the forward and three ribs of the aftward wing.
Cutted from thin plywood or whatever.
There is no need to build the complex wing from the picture in the first place.
Thanks Disabled, that is very true. I have an airfoiled section I will try to see whats going on with it. Your photo gives me a great idea on how to do the linkage.
Ok, enough talk, lets see if I can get started before I go to work in about 45 minutes!! lol
Bob, thanks for the heads up, you are right, if I let the wind induce the twist, the only twist I will get is opposite to what it is desired, basically loosing the camber in the wing.
My theory says: high aspect ration = higher speeds.
