If you're not scared of a bit of math, this page will help you put your CG in the ballpark:

http://www.zenithair.com/kit-data/ht-90-4.html

C/L planes seem to want a pretty far-forward CG, but not as far as you're going to get!  I'm guessing that before you're done you will wish that you had notched the horizontal stabilizer significantly, to set the motor back as far as possible.

Let us know how it comes out!

Here's a coupla pix of my current project, a canard.

If you have older Flying Models magazines, see if you can find the copy with the Sarpoulis "Wild Goose" -- that one puts the engine right in front of the leading edge of the wing, with the canard on booms.

I built the Wild Goose.  Called mine the Blue Goose because of the color.  The engine and tank are ahead of the leading edge.  Balance is about 2 inches in front of leading edge and is a little quick on controls.  Have cut down the movement on the main wing moving surfaces.  Have also moved the leadouts forward a little.  Whn engine is set right it will fly a pattern.  It is different to look at and fly.  May take pictures later.  


Well you asked for it even tho it is not  a 1/2A.  This one a LA 40 for power.

It seems to me that Bob Hunt has a 1/2A Canard with forward sweep in the rear wing.  He said it flew fantastic.  Old Model Aviations had a photo of it in his lead-off editorial column for a while.

So which control surface controls planes attitude. Those are both nice looking designs. Doc, thats the best looking wild goose i've ever seen.

So which control surface controls planes attitude. Those are both nice looking designs. Doc, thats the best looking wild goose i've ever seen.

The forward moving surface does the work.  The flaps on the wing I think could be made solid and help a lot.  I reality I did cut the movement down on both moving surfaces.  Have the tallest horn I can find on both.  I built it originally because some people stated canards can't do the pattern.  I have witnesses that have seen me do it when I am on.  It just looks strange on the end of the lines.  Instead of rotating like a conventional stunt plane it just pitches up or down.  It is a fun plane to fly and get attention.

My first attempt at a canard, a few years ago, used an elevator at the front and flaps at the back. After the first flight (wild!) I unhooked the back wingflaps and fixed them in place.  It helped a lot.  This one will have elevator-only, in the front.

Progress is slow but steady.  I'll post some more pix soon.

Ummmm, where's the fuel tank go?  Otherwise, a very interesting model.  Can't wait for the flight reports!

Do you know why they call them canards?

Cos they "can ardly fly" 

Now there is a name for your plane.

Lionel

Well the Wright Brothers made them fly.

And they were incrediblly lucky they didn't kill themselves.  That 1903 design has proven to be almost unflyable.  A movie made about them used a close replica with extra empenage added at the tail for stablilty so the pilots could survive.  The add-ons were painted black so they wouldn't show up in the movies (this was way before digital editing).

Not to say canards can't fly, Burt Rutan's designs come to mind.

I think the "Canardly" is neat looking!

Just about any aircraft configuration can be made stable or not by correct CG placement and control sensitivities.  The X-29 forward swept, canard aircraft was made purposely unstable to test the computer control systems, but I have photos of a perfectly good, stable flying X-29 scale slope model.  It showed up in a few magazines, and I have seen it fly up close and personal. 

I understand that the F-117 Stealth fighter is trimmed to be inherantly unstable, but the first tests were with an R/C model that flew just fine.  And!!! The model was designed and built by Stunt's very own Bob Palmer.  I had the good fortune to hear the story from his own lips.

While i did not work on it I did have those thoughts when I made my post. The point being that out c/l aerobatics have to work for our slow response times on the end of a 60 ft line. Canard design like the varieze can use it's format to improve flight stability. Thought we are looking for planes that might be more unstable for PA. It might make a good trainer for those starting off.

The Wrights actually built/designed in reaction to the kind of accidents which killed Lillienthal and Pilcher: gust upsets of planes controlled by weight shift and subject to the vagaries of relative wind. They deliberately made their "Flyer" control oriented, rather than auto stable. They wanted laterally and longitudinally  (really regarding all three axes) to control the plane's motions and attitudes. While they anhedralled the wings to direct the plane into, rather than out of side gusts when near the ground,  they wanted to be able to overcome upsets by their own will and skills. So they carefully taught themselves to pilot an unstable plane. They overdid it in the 1904 plane and corrected for that. Remember though that their invention relates to aircraft control, and it was to that end that they designed their plane. At a time when the rest of the world's aviators were just "hopping" with insufficient control, they were flying  round and round Huffman Prairie for times approaching an hour. They had a much more sophisticated knowledge of flight dynamics than most realize, having approached the flight problem very scientifically and methodically, inventing (e.g. the aircraft propeller) along the way. They were aware of stalling phenomena and the forward "rudder" (canard surface), too. They just needed to know about Reynolds numbers, which came later. See their complete note books on the internet, or examples in the archives of the two most active CL forums.

Canards are fun, and I'm always happy to see anyone giving them a try. Don't expect them to match stunt or glide performance of conventional aft-tail planes though, unless they are part of a three-surface configuration. The a.c. and necessary static margin (as well as interference) don't allow the main wing to use it's entire lift potential. There's some good info in the archives, despite the crash. Try also Stanford Aero and  - maybe - NASA (Rutan). Some fairly recent papers/articles (1980 and later) have addressed this.

I like your project and would like Bob Hunt to let us in further on his results with his own configuration. There's a lot to be learned from the unconventional, and winning stunt contests isn't everything (OMG!).

SK

I would guess that they don't do well with figure nines.     

Probably canardly make it through them (devil made me say that)...

George

Ok after posting the canard'ly joke I must say that I did make a canard when I was at school, it had two .049's on it in a push-pull configuration and I had a ton of fun with it it was stable and I could do a wing over and loop with it so yes they do fly.

Lionel.

I have the wing covered and added a rudder, as much for tail weight as anything, but it looks better I think.  Still need to finish the MM and LO guide (highly adjustable, just in cases), then paint.  A little ways away from flight tests.

 I believe I'll go with a Norvel .049 since my TeeDee has a crack at the back of the venturi.

I bent the nose LG leg backward, to improve the AoA on ground, and get it a little closer to the CG (and move a little weight back while I'm at it).  Still tinkering.

Thanks Larry, I was considering JB weld, I've repaired cracks in metal cases with it--wire reinforcement sounds useful too.

Hey c'mon Larry, I been working on some kits dontcha know...

the "Can'ardly" is covered, rudder added, I'll try to post some updated pix.  Not much progress from last report, still needs MM finished, LO guides installed, paint.

Hmmm, maybe I'll put a Holland Hornet on it...

--Ray

as it happens, it's 27.5" span, 6" chord, between 160-165 squares.

Hey Larry, my fault as he had to take time to make one fabulous kit for me.  Have the wings done and fuse almost in place.  I screwed up and hinged the elevator before looking at the fuse.  No problem as I have it figured out already.  May change tank area also.  Taking pictures as I go.   

OK kits are done, Can'ardly back on the workbench...adjustable leadouts installed.  Heres pix if I can get them on here...(new computer, still figuring out the nuances...)  My trusty Norvel .049 rubberbanded to the nose for effect.

How 'bout a profile shot, to show off the landing gear?

Were I you, I would ditch the "kinky" pushrod and install a straight one.  The forces will work out the same, but the flexing will be way less!  The force vectors haven't a clue what goes on between the pivot points, but the wire sure does.  Lighter weight, too.

Otherwise a really cool plane!

Yes, I see your point, but then again you could just cut a notch in the elevator.  The area loss would be negligible.

I await flight tests!  If it turns out to be noseheavy, you could go to a forward swept canard to move its area ahead of the engine.  Also, area outside the booms might help, they need not be, and probably should not be, moveable.  In fact that could be one of the trim tactics to use, depending on how this model flies.