HobbyKing.com New Products Flash Sale
Reply
Thread Tools
Old Jan 29, 2010, 11:42 AM
Registered User
Joined Jun 2005
2,481 Posts
Dereck Woodward
Quote:
That my first canard is an OD is hardly surprising. After all, I learned to fly RC aerobatics by simultaneously designing my first RC aerobatic model. Three of them - do you know how much trouble a flat spin can be when your model won't come out of it? Hope this canard is a little less fuss.

It is an honor to have a viewer who has been around the modeling world as a designer, builder and professional writer. He truly appreciates the building and flying a graceful airplane like the Sig Seniorita.


Nickchud
Quote:
reading Charles' account of watching the ailerons from inside a plane reminded me of this video I took last summer. Once the plane gets up to speed, you can see just how little movement is required by the elevator. I didn't have elevons, only aileron / elevator. And that one is only about 20% of the stabiliser surface.

Nick, Thanks for submitting that!! It gave me a super high as if I were sitting on the nose with all that wind rushing by just like on a motorcycle. I was also reminded of the hand out of the car window which felt the air pressure on the palm regardless of the angle with turbulence on the top. It works like a surfboard or a delta jet landing at a high nose UP angle.


Conehead Orrin
Quote:
I will look for some canards at E-Fest, doubt there will be any, only Jason Noll built one, I will ask him about plans and specs when I see him.
So have fun, been a hoot reading about all the building, flying and such.
Have some fun yourself, Orrin! I hope you see Dereck. His British accent is a real treat.


Jetman
Quote:
Charles, That looks great! I wish I had the time for balsa! It is so much more of an art, I used to love my grandfathers balsa/covered planes, but didn't get back into the hobby before they were thrown away!

Many thanks, Jetman, Balsa is all that I know well. Today is wet so I will spend some time building. Hope to finish the main wing on the Evader. It is coming along much faster than was expected.
Charles
canard addict is offline Find More Posts by canard addict
Reply With Quote
Sign up now
to remove ads between posts
Old Jan 29, 2010, 03:03 PM
Visitor from Reality
United States, VA, Arlington
Joined Dec 1996
12,788 Posts
Ah, Balsa! Perhaps I need to find a craft store and go sniff some

Somewhere miles away, I have a copy of an excellent book on foam modelling by Keith Sparks. It makes it all sound really easy, and I have a feeling if I could get brave enough (and the odd tools that would look really odd in my shop!), foamin' would be fun.

One example I may try when the dust settles - making a FF chuck glider of my canard project. At an IMAA legal, 25% full size and 9" span, I could test glide it down the corridor from condo to elevator area to ascertain at least rough CG and basic stability issues. Such flying test devices used to be made from scrap balsa, but perhaps thin de-papered foamboard or Depron would be better?

Regards

Dereck
Who would love some photos of the canards seen hereabouts, for the column...
Dereck is offline Find More Posts by Dereck
Reply With Quote
Old Jan 29, 2010, 03:14 PM
Registered User
Joined Jun 2005
2,481 Posts
Quote:
Dereck
Who would love some photos of the canards seen hereabouts, for the column...

The chuck gliders get credit for giving me the confidence and ambition to upscale and build. You will receive a shot of my Evader before it gets roughed up.
Charles
canard addict is offline Find More Posts by canard addict
Reply With Quote
Old Jan 29, 2010, 03:49 PM
Flutter-Bys are fun
Conehead's Avatar
United States, MI, Honor
Joined Dec 2005
5,117 Posts
Dereck,
i will look for you. You can find my by my Flutter-Duck. I will bring it in if there is enough room. Has not flown yet by me. Jack, the builder has flown it, but alas, not me, way too cold, too much wind and I don't want to smack it up on the ice on the lake. I can wait.
There are lots of other things that I can do. I will have a camera also, just an old Kodak digital one. Works fine for me and if I want great pictures, I will go to Mark and ask him for some.
Off to E-Fest in a few minutes. I am in the motel now.
Conehead
Orrin Eldred
Conehead is offline Find More Posts by Conehead
RCG Plus Member
Latest blog entry: TRAMPS Air Show, 28-June 2014
Reply With Quote
Old Jan 30, 2010, 12:51 AM
Registered User
Herndon, VA
Joined Oct 2005
1,471 Posts
Charles, that little Scorpion looks awesome! What's the KV on there?
RE
Edmonds is offline Find More Posts by Edmonds
Reply With Quote
Old Jan 30, 2010, 03:11 AM
What could possibly go wrong?
nickchud's Avatar
Market Harborough
Joined Apr 2006
3,791 Posts
Looks like 1920Kv. Quite fast, I think. Are you using 2cell batteries, or 3?

She's going to be a beauty. No dihedral? My Lillycat tends to come into land sideways with low power. Adds to the interest and she can do a very passable knife-edge. Maybe I'm wrong to put those things down to having a flat wing?

Keep on keeping on.

cheers

Nick
nickchud is offline Find More Posts by nickchud
Reply With Quote
Old Jan 30, 2010, 08:50 AM
Onward through the fog.
Cybernaught's Avatar
Bohol Philippines
Joined Aug 2008
1,566 Posts
Looks like you're making good progress there, Charles. Balsa does give a good light airframe. Good luck with it.

Gosling is finished, just waiting for the weather to cooperate and experimental fixed-canard plane started. I'm trying some new ideas for the construction method on this one to hopefully keep it lighter and speed up construction. Kind of a modular build.

Charles and the rest of you experts give me your two-cents-worth on this.

The fixed canard area will be 33% of main wing's with the elevator 40% of the total canard area. The chord ratio for the main wing and canard is the same, with a swept leading edge and straight trailing edge. Tip chord is 65% of the center chord for both wings. Both foils will be KFm2s with the same thickness and flat bottomed on the same level which will actually provide the canard with about 3 degrees more incidence. Motor thrust line will be in line with the wings. Main wing is 3 sq ft, 36" span with an average chord of 12". Canard is 22" span with an average chord of 6.666" leading edge to main-wing leading edge is appx. 15" on about a 30" fuselage length. The build dimensions I'm using I got from values I found on this thread in various posts and advice given here and there. If it's light enough I'll use a BW motor but can use a FC2228 or BP21 with a bigger battery if necessary.
The plan is to have the controls set up for aileron/elevator/throttle.

This should be interesting.

I do like that Lillycat. Looks like there is a lot going on here...

Steve.
Cybernaught is offline Find More Posts by Cybernaught
Last edited by Cybernaught; Jan 30, 2010 at 08:56 AM.
Reply With Quote
Old Jan 30, 2010, 11:36 AM
Registered User
Joined Jun 2005
2,481 Posts
Nickchud
Quote:
Looks like 1920Kv. Quite fast, I think. Are you using 2cell batteries, or 3?

She's going to be a beauty. No dihedral? My Lillycat tends to come into land sideways with low power. Adds to the interest and she can do a very passable knife-edge. Maybe I'm wrong to put those things down to having a flat wing?
1920kv is correct. Scorpion claims it will pull about 18 amps on three cells for about 190 watts in at near 18100 rpm and 69 mph pitch speed at 24 ounces of thrust. The motor was very low cost with further discounts available so I hear. If it does produce what it claims at decent efficiency, it should push the model well enough. The Egret weighs 28 ounces and I really hope for 32 for this model since the main fuselage could be less. I hate to fall below 80 watts per pound.
I depend on the wing's LE sweep back for dihedral effect. My first Goose had the same wing with dihedral and it rocked in turbulent air. If this model flies well, rudder can be added for a wicked flat spin. With symmetrical airfoils it could be fully aerobatic.


Cybernaught Steve
Quote:
Charles and the rest of you experts give me your two-cents-worth on this.

The fixed canard area will be 33% of main wing's with the elevator 40% of the total canard area. The chord ratio for the main wing and canard is the same, with a swept leading edge and straight trailing edge. Tip chord is 65% of the center chord for both wings. Both foils will be KFm2s with the same thickness and flat bottomed on the same level which will actually provide the canard with about 3 degrees more incidence. Motor thrust line will be in line with the wings. Main wing is 3 sq ft, 36" span with an average chord of 12". Canard is 22" span with an average chord of 6.666" leading edge to main-wing leading edge is appx. 15" on about a 30" fuselage length. The build dimensions I'm using I got from values I found on this thread in various posts and advice given here and there. If it's light enough I'll use a BW motor but can use a FC2228 or BP21 with a bigger battery if necessary.
The plan is to have the controls set up for aileron/elevator/throttle.
Sounds like a double delta, Steve. Please give us the center and tip chords of both wings to save some work. I will be nervous until you fly the Gosling. Please wait on a calm day to try it. You do have calm days don't you??
Charles
canard addict is offline Find More Posts by canard addict
Reply With Quote
Old Jan 30, 2010, 04:57 PM
Onward through the fog.
Cybernaught's Avatar
Bohol Philippines
Joined Aug 2008
1,566 Posts
Quote:
Originally Posted by canard addict View Post
Nickchud

1920kv is correct. Scorpion claims it will pull about 18 amps on three cells for about 190 watts in at near 18100 rpm and 69 mph pitch speed at 24 ounces of thrust. The motor was very low cost with further discounts available so I hear. If it does produce what it claims at decent efficiency, it should push the model well enough. The Egret weighs 28 ounces and I really hope for 32 for this model since the main fuselage could be less. I hate to fall below 80 watts per pound.
I depend on the wing's LE sweep back for dihedral effect. My first Goose had the same wing with dihedral and it rocked in turbulent air. If this model flies well, rudder can be added for a wicked flat spin. With symmetrical airfoils it could be fully aerobatic.
Do you have a link to pictures of the scorpion? I want to see what it looks like.


Quote:
Originally Posted by canard addict View Post
Cybernaught Steve

Sounds like a double delta, Steve. Please give us the center and tip chords of both wings to save some work. I will be nervous until you fly the Gosling. Please wait on a calm day to try it. You do have calm days don't you??
Charles
Charles, We have calm "Moments"...

Here is a couple of pictures of what I have so far. The drawing shows the details of the dimensions. Dimensions may vary slightly...
Canard Center Chord = 7.75" Tip Chord = 5"
Main Wing Center Chord = 14" Tip Chord = 10

The drawing doesn't show the 2" additional chord for the ailerons.

Any comments or suggestions are appreciated and remember, I"m new to canards.

Steve.


"Specs" added to pictures.
Canard root chord is 7.5"fnot 7.75" as maked.


Edit: Jan 31, 2010 8:50am
Maiden completed with the Gosling. Not the best but it files. Now to get some stick time...
Gosling Maiden.mp4 (2 min 3 sec)

Cybernaught is offline Find More Posts by Cybernaught
Last edited by Cybernaught; Jan 30, 2010 at 07:57 PM.
Reply With Quote
Old Jan 30, 2010, 09:07 PM
Registered User
Joined Jun 2005
2,481 Posts
Steve, Check here for Scorpion:
http://www.bmkdesigns.net/Scorpion-2...or-pr-473.html

Your new design was drawn and to me it looks like a delta with gaps cut out on each side which is out of my league but it probably will do well. I would let the fins start about mid chord and let them extend 4" behind the TE. Elevons and elevator should work well. It probably will be quick. I will show my Dixie Delta again which can run with the 40 trainers.
Charles
canard addict is offline Find More Posts by canard addict
Reply With Quote
Old Jan 30, 2010, 10:51 PM
Onward through the fog.
Cybernaught's Avatar
Bohol Philippines
Joined Aug 2008
1,566 Posts
Quote:
Originally Posted by canard addict View Post
Steve, Check here for Scorpion:
http://www.bmkdesigns.net/Scorpion-2...or-pr-473.html

Your new design was drawn and to me it looks like a delta with gaps cut out on each side which is out of my league but it probably will do well. I would let the fins start about mid chord and let them extend 4" behind the TE. Elevons and elevator should work well. It probably will be quick. I will show my Dixie Delta again which can run with the 40 trainers.
Charles
I thought the scorpion was a plane you built.

What do you mean: "You new plane was drawn."??? Do you have some RC software that I want???

It's not intended to be a delta. I am using what I thought was the Georgia Goose wing with a low AR. I like the shorter span to give a sturdier wing without reinforcement and a better roll rate. My main intent is to test some building ideas with this plane and to see how I like the fixed canard idea.

We have gale force winds again about noon local time. The wind started when I got to the field to maiden the Gosling, just after 7am. Sheesh!!

I like the Dixie Delta but I'm not keen on tractor drive. I like pushers for safety reasons and anything with the name "Dixie" is not PC... Could be considered racist nomenclature..... Hee Hee.

Steve.
Cybernaught is offline Find More Posts by Cybernaught
Reply With Quote
Old Jan 30, 2010, 11:33 PM
Flutter-Bys are fun
Conehead's Avatar
United States, MI, Honor
Joined Dec 2005
5,117 Posts
I got to talk to Dereck today, he shot pictures of my Duck, checked it out and went over it with a fine tooth comb and I think if he had a magnifying glass he would have inspected every inch of it.
We had a delightful conversation, I love his British accent and of course he is RAF.
he took notes on my Duck, photos, then more of the other planes, the Flutter-By's and then he even took a picture of me with my mini-Flutter-By, he wants to put in a column in the future.
I look like a raggy Ann doll since I have a few weeks beard since it has been rather cold up north.
Conehead
Orrin Eldred
Conehead is offline Find More Posts by Conehead
RCG Plus Member
Latest blog entry: TRAMPS Air Show, 28-June 2014
Reply With Quote
Old Jan 31, 2010, 12:21 AM
Registered User
Joined Jun 2005
2,481 Posts
Steve, I took the dimensions of your new model and put it on paper to look at and found it to be compact and different from the Goose concept which has it's long fuselage and near 6 for aspect ratio. It seems that the Gosling favored the Goose from your pictures. How did it handle? I feel that the new model will do OK with fixed canard and elevators. Since it is short coupled, the front wing probably will work at zero angle. I enjoy the pusher types for safety also but still have a few tractors in the fleet. Most of my models have landing gear and a safety switch which is turned ON just before take off when I am safely away from the prop. You will probably enjoy the elevator set up since you have elevons.
Charles
canard addict is offline Find More Posts by canard addict
Reply With Quote
Old Jan 31, 2010, 02:07 AM
Onward through the fog.
Cybernaught's Avatar
Bohol Philippines
Joined Aug 2008
1,566 Posts
Quote:
Originally Posted by canard addict View Post
Steve, I took the dimensions of your new model and put it on paper to look at and found it to be compact and different from the Goose concept which has it's long fuselage and near 6 for aspect ratio. It seems that the Gosling favored the Goose from your pictures. How did it handle? I feel that the new model will do OK with fixed canard and elevators. Since it is short coupled, the front wing probably will work at zero angle. I enjoy the pusher types for safety also but still have a few tractors in the fleet. Most of my models have landing gear and a safety switch which is turned ON just before take off when I am safely away from the prop. You will probably enjoy the elevator set up since you have elevons.
Charles
The Gosling, at first wasn't very responsive to roll input. I had problems getting it to turn so I increased the elevon throws. Didn't fly again because the wind came up pretty strong. The problem might have been because of the tip-hedral. It was very stable in roll when going straight. Pitch was good.

Current build has a mind of it's own. It's not coming out anything like I envisioned it. Main thing is to try flying a fixed canard without mixing the elevator with elevons. This will be canard for pitch and ailerons for roll only. The canard's elevators will be proportionally large. The modular approach is to finish the main parts, including pop bottle reinforcements and colored tape, then glue it up before installing the gear. It's nothing like the Goose and I have no control when I build. I just "GO" and it comes out like it comes out??? There's no planning really and no discipline. The ideas just seem to cascade in and I just do them. One or two basic concepts seem to be retained but everything else is "loosy-goosey". No pun intended.

Steve.
Cybernaught is offline Find More Posts by Cybernaught
Reply With Quote
Reply


Thread Tools