canard CG
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I'm wanting to design/build a canard fun fly plane. Does anyone know of a good web site or have info on how to balance a canard aircraft? All of the canard planes I have seen are like the EZ plane.
Any help would be appreciated.
Thanks
Jack
Any help would be appreciated.
Thanks
Jack
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Adrian,
That graphic method works well for conventional airplanes but doesnt take into account the physics of a canard. If it is used to calculate the CG for a canard odds are the airplane will be tail heavy.
Jack & Adrain,
If you like you can send me a PM and I can e-mail a mag article to you that covers basic canards pretty well. Warning - Some algebra
may be involved for the calculations.
Just a note; I have faith in the info because I built a small glider to test the math
Cheers.
James
That graphic method works well for conventional airplanes but doesnt take into account the physics of a canard. If it is used to calculate the CG for a canard odds are the airplane will be tail heavy.
Jack & Adrain,
If you like you can send me a PM and I can e-mail a mag article to you that covers basic canards pretty well. Warning - Some algebra
may be involved for the calculations.
Just a note; I have faith in the info because I built a small glider to test the math
Cheers.
James
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canard CG
I used a program out of a magazine one time that showed cg and size of canard required. We used it to design a glider but I have no clue as to where the program went. It was in basic and was a lot of code to type. I had it working well, but that was long ago. I think we got it out of RCM a in the mid 80s. Might be the one James is talking about.
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There is some discussion going on over in the Aerodynamics forum about canard CG calculation. I posted a link to Ron Van Putte's formulas in a M.A. article that worked for me in a canard design I did some time ago. Read this thread: http://www.rcuniverse.com/showthread...369&forumid=19
HTH )
HTH )
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Thanks HTH.
Thats the one. I have a copy of that file on my other puter at home. Couldnt remember the author.
Didnt use the calcs for the fin area cause I was going off a scale subject. So no comment on those numbers.
Cheers.
Thats the one. I have a copy of that file on my other puter at home. Couldnt remember the author.
Didnt use the calcs for the fin area cause I was going off a scale subject. So no comment on those numbers.
Cheers.
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Originally posted by mdlav8r
Thanks HTH.
Thanks HTH.
Regards,
Milton Dickey
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Canard CG
If anyone is interested I got a copy of an Excell spreadsheet a couple of years ago which will calculate the CG of canards, bi-planes, monoplanes, swept and tapered wings. It will also do the design calculations. you just plug in the span, chord etc. If anyone would like to have a copy let me know.
Will Varnado
Will Varnado
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wvarn1957, I would love a copy of that program
Hey there WVARN,
I would love a copy of that Excell spreadsheet. I have gotten hooked on building scratch built foamies in electric and small sail planes. That would help a lot on future projets.
I'll be adding my new v-tail sail plane to the gallery as soon as I am done with it. (very soon!) Wing design had too much drag but is at 13OZ! Flies, but will be better after a different wing is on it. Looks like it will stay up forever untill forward speed drops off due to drag and then down it comes with a fast sink rate like there are spoiler up.
Back to the drawing board.
[email protected]
I would love a copy of that Excell spreadsheet. I have gotten hooked on building scratch built foamies in electric and small sail planes. That would help a lot on future projets.
I'll be adding my new v-tail sail plane to the gallery as soon as I am done with it. (very soon!) Wing design had too much drag but is at 13OZ! Flies, but will be better after a different wing is on it. Looks like it will stay up forever untill forward speed drops off due to drag and then down it comes with a fast sink rate like there are spoiler up.
Back to the drawing board.
[email protected]
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Hi WVARN - I would like a copy of that speadsheet too. A friend called me last evening to say that he is building a canard and asked if I know how to calculate the CG. His version will have swept wings and tip fins!
Regards to all
Gordon
from way down here in Wellington, NZ
Regards to all
Gordon
from way down here in Wellington, NZ
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canard CG
The link to download the excel sheet is available on this thread i think..
http://www.rcuniverse.com/showthread...474&forumid=19]
http://www.rcuniverse.com/showthread...474&forumid=19]
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Canard CG
Hi everybody,
I have some recent experience with a large canard airplane, and found that, regardless of the formula you use, the fact is that it really depends on the lifting potential of the canard.
In the case of the plane I worked on, I found that what "should have" worked didn't... By increasing the span of the canard, switching airfoils, (to an Eppler 197) and increasng the proportion of elevator to canard. (elevator was about 30% of the canard chord) everything worked great. (Andy Lennon's book, "The Basics of RC Model Aircraft Design", available through Model Airplane News, helps a lot.) I found that if the canard chord drops below about 5 inches, you may as well use sheet balsa, as opposed to an airfoil. (Reynolds effect, especially at lower airspeed)
One bit of good news...
Since canard aircraft generally have a wider safe CG range than conventional aircraft, you might find that simply moving the CG a bit aft will help a lot.
When they're right, they're fun!
Happy flying!
I have some recent experience with a large canard airplane, and found that, regardless of the formula you use, the fact is that it really depends on the lifting potential of the canard.
In the case of the plane I worked on, I found that what "should have" worked didn't... By increasing the span of the canard, switching airfoils, (to an Eppler 197) and increasng the proportion of elevator to canard. (elevator was about 30% of the canard chord) everything worked great. (Andy Lennon's book, "The Basics of RC Model Aircraft Design", available through Model Airplane News, helps a lot.) I found that if the canard chord drops below about 5 inches, you may as well use sheet balsa, as opposed to an airfoil. (Reynolds effect, especially at lower airspeed)
One bit of good news...
Since canard aircraft generally have a wider safe CG range than conventional aircraft, you might find that simply moving the CG a bit aft will help a lot.
When they're right, they're fun!
Happy flying!
#16
canard CG
Here is the article by Ron Van Putte, June1980, Model Aviation on canard CG and vertical fin sizing
http://www.angelfire.com/scifi2/wiza...es/Canards.zip
It covers the major equations that were used in my spread sheet referenced in the thread above.
Alan
http://www.angelfire.com/scifi2/wiza...es/Canards.zip
It covers the major equations that were used in my spread sheet referenced in the thread above.
Alan
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Hi Guys,
I currently have a Ducted Fan Canard jet in the early-to-mid design phase. I have a spreadsheet that I put together for calculating static stability. It's in pretty rough shape right now, but I could polish it up and make it available on my website.
Just let me know who's interested.
Ken - www.litkoaero.com
R/C Laser Cutting and Design
I currently have a Ducted Fan Canard jet in the early-to-mid design phase. I have a spreadsheet that I put together for calculating static stability. It's in pretty rough shape right now, but I could polish it up and make it available on my website.
Just let me know who's interested.
Ken - www.litkoaero.com
R/C Laser Cutting and Design
#18
canard CG
CG calculations :
The most efficient way is to build a reduced version of your canard as a glider and hand launch it from a litlle hill, facing the wind.
Is is relevant to check the grass is high enough underneath, otherwise, finding the right Cg may be a very lengthy process...
The most efficient way is to build a reduced version of your canard as a glider and hand launch it from a litlle hill, facing the wind.
Is is relevant to check the grass is high enough underneath, otherwise, finding the right Cg may be a very lengthy process...