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Author Topic: Canardly Fly .  (Read 242767 times)

Offline Air Ministry .

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Canardly Fly .
« on: January 11, 2015, 05:52:21 PM »


wouldve made their lives easier if theyed invented JETS , save the pavement ;



this horrible creten looks like itd be quite straightforward , semi scale . VD~ S?P
other than a Leadout thingo sticking out , and a extension drive to keep it mid engined,
with all the cooling ducts similar to F. S. . Cant see why itd need flaps . but does this mean
the AIRFOIL unflapped'd be not entirely related to a flapped ( F2B ) Airfoil . :-\

looks fairly straightforward .  ;D LL~

Offline Tim Wescott

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Re: Canardly Fly .
« Reply #1 on: January 11, 2015, 06:30:19 PM »
So what's the airplane?  Clearly it's not a Piper Cub.
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Online Trostle

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Re: Canardly Fly .
« Reply #2 on: January 11, 2015, 07:45:44 PM »
Interesting video of the Kyushu J7W Shinden at



The prototype flew just before the end of the war.

An RC version by Col Bob Thacker appeared in Model Builder, August 1984, 62" span.

Keith

Offline Air Ministry .

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Re: Canardly Fly .
« Reply #3 on: January 16, 2015, 07:29:33 PM »
Id be intrested in opinions on airfoils etc , for a ' proper ' F2B version . Reading Radio canard stuff , they seem to think the 'turn ' is NOT as tight , without the prop thrust on the foreplane .



thats the three view . One german canrd had a long aft fuse for conventional Vert Stab orientation , and a Carbon Fibre prop shaft to tractor prop ,engine on the C.G. . in flying muddles .

Offline Akihiro Danjo

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Re: Canardly Fly .
« Reply #4 on: January 17, 2015, 07:07:18 AM »
This is my Shinden, built from a classic Japanese kit (still in production by KMCo, in Japan), powered by OS CV15.
The performance is sooo poor because it is heavy, in addition it needs lots of nose weight.
Aki

Offline Tim Wescott

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Re: Canardly Fly .
« Reply #5 on: January 17, 2015, 11:21:07 AM »
If you just want to build a canard, then check out Dick Sarpoulis's "Wild Goose" from Flying Models.

Possibly the best way to do a rear-propped plane would be with 'lectric, although a shaft drive to remove the need for nose weight is the best way to do it with a piston engine, in my opinion.  Around the same time that he did the "Wild Goose", Sarpoulis did a Hanriot-Bische 110 for control-line, with a front-mounted motor, shaft, and pusher prop.  He used the pressure fitting on the muffler to source lubricating oil to the rear bearings.
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The problem with electric is that once you get the smoke generator and sound system installed, the plane is too heavy.

Offline Howard Rush

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Re: Canardly Fly .
« Reply #6 on: January 17, 2015, 01:48:28 PM »
Shinden drawings I saw showed a floating canard, which would have allowed the CG to go farther back. 
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Online Brett Buck

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Re: Canardly Fly .
« Reply #7 on: January 17, 2015, 02:22:01 PM »
Id be intrested in opinions on airfoils etc , for a ' proper ' F2B version . Reading Radio canard stuff , they seem to think the 'turn ' is NOT as tight , without the prop thrust on the foreplane .

   And by cambering the wing in the *wrong direction*!

    Brett

Offline Mike Keville

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Re: Canardly Fly .
« Reply #8 on: January 17, 2015, 08:21:18 PM »
This thread brings back memories of VSC-III and Jim Renkar's canard "Can Stunt", a Paul Del Gatto design in FM.  Repeated attempts to break ground were, shall we say, "less than successful" - after which Jim borrowed a marker pen and wrote on the wing, re-naming it "Can'T Stunt".  Photo attached.
FORMER member, "Academy of Multi-rotors & ARFs".

Offline PerttiMe

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Re: Canardly Fly .
« Reply #9 on: January 18, 2015, 03:50:32 AM »
I think Bob Hunt has built some canards too. Not sure if I ever saw a word about how they worked out.

With a swept wing, leadout guides well forward of wingtips will be necessary.
I built a Blue Pants as a kid. Wish I still had it. Might even learn to fly it.

Online Bob Hunt

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Re: Canardly Fly .
« Reply #10 on: January 18, 2015, 09:53:00 AM »
Yeah, I'm afflicted with the canard bug... It's worse than Malaria... Or so it seems.

Actually, my father got me interested in canards. He had a really big one in the mid 1950s that flew okay, but it porpoised in level flight as did many others that were built with straight wings and twin booms going forward to the stab and elev mount. We discussed this a lot, and my good friend, Dean Pappas also got in the discussion. The reasoning was that the CP and the CG are too far apart on the normal configuration that is most often used. The model flies off of one or the other until a certain angle of attack is reached, and then it reverts to the other point. The proposed fix was to sweep the wing forward to allow the CP and the CG to be closer together.

The first design that I tried that on ultimately flew extremely well, but only after increasing the elevator area by 150 percent. It seems that the artificial airspeed over the elevator in a normal configuration design is required for proper response. I added the area, and then, at Dean's insistence, added a bunch of nose weight. Glad I did; the ship was still tail heavy! Once we got the CG correct and had the proper amount of elevator area, the ship flew flawlessly. I can't tell you why I haven't persued the canard seriously, as I really believe there is something to them. I did build another one a few years back, but was impatient to test fly it and chose a way-too-windy day. Result: splinters. Trust me, there will be more canards coming from my shop!

Later - Bob Hunt

Offline Wolfgang Nieuwkamp

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Re: Canardly Fly .
« Reply #11 on: January 18, 2015, 12:46:32 PM »
Many years ago I built a canard with forward wing rake. It flew well, except some hunting in level flight, but I never could tame the FOX 45…
It was destroyed because of a line connector failure. An electric version is planned.

Offline Tim Wescott

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Re: Canardly Fly .
« Reply #12 on: January 18, 2015, 03:37:43 PM »
Just an observation: any airplane that is balanced to be stable, and that has two surfaces (wing & tail, wing & canard, or two wings), will always have to have a greater change in coefficient of lift of the front surface than the rear to effect pitch changes.  For symmetrical surfaces, the front surface will always need a greater coefficient of lift, period.

I'm not sure, but this makes me think that it would be beneficial to have at least the fixed part of one's canard foreplane be fairly thick, so that it can gracefully generate lots of lift in the square corners.
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The problem with electric is that once you get the smoke generator and sound system installed, the plane is too heavy.

Offline Air Ministry .

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Re: Canardly Fly .
« Reply #13 on: January 18, 2015, 06:38:57 PM »
Got a olde French magazine with THIS in it . a R/C ( two channel ? ) racer , for .049 to .015 . Flying foreplane .



foreplane airfoils about the same as the wing , maybe 10 % .
spans about 33 in ( to use 36 in. sheet / spars , presumeably )
fairly cunning contrivance , so may try it C/l to see what happens .
C.G. is shown a bout 2 in behind L.E. at fuse .

another sketch in the mag. shows a spacehoundish square canopy
thatd work as a good cowl , with a mid mounted FSR 25 and tank at C.G.
with slightly less slopeing rear deck .
A N.A.C.a. intake on top deck fwd. of canopy & open outlet aft should get the cooling airflow o.k.
Id use 48 odd for the FSR , ive got some 9x6 pusher props , and been looking for a ' light hack '
for the ball race 25 , so it looks like it might do it . And similar enough to the shinden for a info
cross over if it works . Good Excuse for a flying Tailplane too , though its a foreplane Im Told .

havnt searched through the French Site where I found the photo . Theres a few FAI T/R ships on that page ,
http://docmodeli.free.fr/rubriques/plans/index.php?pageNum_modeles=+++++++++++++++++++++++29&totalRows_modeles=3781&criteres
so theres a chance theres a few F2B ships on board too . ?

Offline Tim Wescott

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Re: Canardly Fly .
« Reply #14 on: January 18, 2015, 06:49:08 PM »
RC flyers get to stuff all their radio equipment up in the front of the plane.  We can't spread necessary weight out like that, unless we want to fly electric.

But yes, it looks cool.
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The problem with electric is that once you get the smoke generator and sound system installed, the plane is too heavy.

Online Brett Buck

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Re: Canardly Fly .
« Reply #15 on: January 18, 2015, 10:39:00 PM »
The reasoning was that the CP and the CG are too far apart on the normal configuration that is most often used. The model flies off of one or the other until a certain angle of attack is reached, and then it reverts to the other point.

    If it is flying in stable level flight, the CG and CP (of the entire airplane) has to be exactly on top of each other. If it is hunting (heh) up and down the CP is moving moving forward and aft of the CG. It can't "fly off of one or the other".

    I would propose that it is/was unstable at low AoA, probably because the CP moves aft at the AoA increased (and hence moves forward as the AoA goes down). Sweeping the wing forward helps by reducing the CP shift by effectively "shortening" the airplane.

   I see that you noticed the other issue - no flaps!

    Brett

Offline FLOYD CARTER

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Re: Canardly Fly .
« Reply #16 on: January 19, 2015, 12:26:41 PM »
My canard experience is limited to an R/C glider, which was not successful (because I didn't know what I was doing).

I remember that Tommie Lay built a stunt canard, but I don't know how it went.  Does anyone have that info?

Floyd
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Offline Tim Wescott

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Re: Canardly Fly .
« Reply #17 on: January 19, 2015, 05:21:47 PM »
I see that you noticed the other issue - no flaps!

As far as I can tell, flaps aren't useful because they help make the airplane turn a tighter corner (induced drag seems to be the limiting factor there), but rather because they can control what point the aircraft rotates around.

So I'm not sure how much flaps are really useful on a canard, or even which direction you'd want them to work -- I'd have to fly one or see one fly before I formed an opinion.
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The problem with electric is that once you get the smoke generator and sound system installed, the plane is too heavy.

Offline Air Ministry .

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Re: Canardly Fly .
« Reply #18 on: January 19, 2015, 06:24:58 PM »
People would probably freak out if they saw one of these overhead these days . " Wheres the Body . o.m.g. "  :##


Wondering WHY we cant treat it as a flying wing , with a ' turn thing ' forward . If the Foreplane was getting Zero Lift would the C.G. be as appropriate to the XB 36 ??
C.G. on that must be somewhere back before the mainwheels .The Symetrical airfoils on the French thing have the foreplane at +2deg. incedance

Online Trostle

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Re: Canardly Fly .
« Reply #19 on: January 19, 2015, 06:33:49 PM »
My canard experience is limited to an R/C glider, which was not successful (because I didn't know what I was doing).

I remember that Tommie Lay built a stunt canard, but I don't know how it went.  Does anyone have that info?

Floyd

Hi Floyd,

Tom seriously went to a lot of trouble to research that canard he build and flew (or tried to fly).  I could go back to find the names involved and where and how he came up with plans.  Supposedly, the model was built to plans that a person built either in the late 40's or more probbly, the early 50's, like around 50 or 51.  It was flown at the Nats, and there was a report that Geroge aldrich commented that it flew the tightest coners he had ever seen.  That was the inspiration the Tom used to learn more about the airplane.    I do not know where he found any plans.  Anyway, Tom built it.  I was with Tom when he first tried to fly it at Whittier Narrows.  As I remember, he was barely able to get it off of the ground after several tries.  Sometime later, he had changed the CG or something.  I think he brought to VSC one year.  But it would barely do a loop, if that.  Whatever was flown that George witnessed years ago was certainly not what Tom's plane was.

Offline Tim Wescott

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Re: Canardly Fly .
« Reply #20 on: January 19, 2015, 06:50:17 PM »
Wondering WHY we cant treat it as a flying wing , with a ' turn thing ' forward . If the Foreplane was getting Zero Lift would the C.G. be as appropriate to the XB 36 ??

If the foreplane were always getting zero lift -- yes.  But that's not the case: the foreplane's lift will change with angle of attack.  Since the foreplane is tied to the fuselage, as the plane pitches up the foreplane's lift will increase.  Basically, as you move the foreplane forward, or make it bigger, you need to move the CG forward to compensate.

Somewhere, bouncing around on the web, there's a set of instructions for determining the CG for an aircraft.  I just googled for it and didn't find it.  It's simplified, but it basically lets you plug in the wing and tail positions, and figure from that the necessary CG location.  The interesting point with it is that you can start with a zero-area rear surface and get a figure that's about 20% of the MAC back from the leading edge (it's for full scale, not CL).  Then as you make the rear surface larger, the stable CG point moves aft.  Once the rear surface is as big as the front surface (i.e., a tandem wing), you can start making the front surface smaller -- the stable CG will continue moving backwards, until finally the front wing has disappeared and the CG is 20% of the MAC behind the leading edge of the "rear" wing.

Edit: http://exp-aircraft.com/library/heintz/stabilty.html
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Offline Wolfgang Nieuwkamp

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Re: Canardly Fly .
« Reply #21 on: January 20, 2015, 03:02:38 AM »
Ron van Putte´s article on canard CG worked for me.

Offline Howard Rush

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Re: Canardly Fly .
« Reply #22 on: January 20, 2015, 06:57:40 AM »
But that's not the case: the foreplane's lift will change with angle of attack.

Not necessarily.  I don't think it did on the Shinden.
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Offline Tim Wescott

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Re: Canardly Fly .
« Reply #23 on: January 20, 2015, 09:50:34 AM »
Not necessarily.  I don't think it did on the Shinden.

I was trying to keep the discussion centered around things we might build to fly in circles with.

I would really like to know how the Shinden was put together.  It would seem that if it had a "floating" foreplane that was connected to the stick, the stability of the airplane would depend on the pilot not holding the stick rigidly -- if you got a pilot who grabbed the stick and locked their elbow, then suddenly the whole assembly would be unstable.

(I'm assuming that by "floating" you mean a foreplane that's pivoted well ahead of it's MAC, and which without pilot input just follows the slip-stream).

If you tried to build such a "floating" foreplane in a stunt ship, but connected it rigidly to a bellcrank, I suspect that it would act fairly rigid, no matter how the pilot held the handle, due to the action of drag and inertia on the flying lines.
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Offline Howard Rush

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Re: Canardly Fly .
« Reply #24 on: January 20, 2015, 02:12:35 PM »
You let the main canard surface float and drive a tab on the back.  Better yet, you drive a stabilator behind the canard. 

Another way to do it is to have an airfoil that has pretty constant lift coefficient over a range of angle of attack.  This is what the TU-144 had: http://www.flightglobal.com/FlightPDFArchive/1973/1973%20-%200009.PDF .  I couldn't figure out how to do this over a big range of angle of attack in both directions.  A rotating cylinder would work, but it would be hard to change direction fast enough for the transition in eights.
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Offline Howard Rush

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Re: Canardly Fly .
« Reply #25 on: January 20, 2015, 02:18:34 PM »
Ron van Putte´s article on canard CG worked for me.

It's the usual simplification.  It doesn't quite provide the understanding one needs to get clues about how one could innovate.  I think experimentation would be more useful.
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Offline Tim Wescott

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Re: Canardly Fly .
« Reply #26 on: January 20, 2015, 03:22:17 PM »
You let the main canard surface float and drive a tab on the back.  Better yet, you drive a stabilator behind the canard. 

That would work as long as they're not servo tabs that act to keep the thing centered.  The XF10F tried what you're suggesting, and had serious problems with response speed : https://en.wikipedia.org/wiki/Grumman_XF10F_Jaguar.  Of course, they were trying to make something that worked over a much higher speed range than we need.

Another way to do it is to have an airfoil that has pretty constant lift coefficient over a range of angle of attack.  This is what the TU-144 had: http://www.flightglobal.com/FlightPDFArchive/1973/1973%20-%200009.PDF .  I couldn't figure out how to do this over a big range of angle of attack in both directions.  A rotating cylinder would work, but it would be hard to change direction fast enough for the transition in eights.

That's an interesting idea, but I agree with you that it's hard to do for a stunter.

I think the problem of trying for a canard that does not contribute to stability is that one ends up, basically, with a flying wing's stability issues.  Given that modern stunters tend to long tails, and long tails tend to enhance "groove", I would think that's the wrong direction to take things.
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Online Brett Buck

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Re: Canardly Fly .
« Reply #27 on: January 21, 2015, 10:59:17 AM »
You let the main canard surface float and drive a tab on the back.  Better yet, you drive a stabilator behind the canard.  . 

   
   Oh. I didn't ever get that part in the previous thread.

    I still think, stability aside, you still want the wing cambered the right way in the corners and I haven't seen any good answers on how it winds up better than what we are currently doing.

Quote
A rotating cylinder would work, but it would be hard to change direction fast enough for the transition in eights.

    Until you hung it, then it goes over the left field fence.

   Brett

   

Online Bob Hunt

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Re: Canardly Fly .
« Reply #28 on: January 21, 2015, 03:32:13 PM »
Wouldn't that technically be a "rotating sphere?"  <=
 
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Offline Tim Wescott

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Re: Canardly Fly .
« Reply #29 on: January 21, 2015, 04:23:40 PM »
... and I haven't seen any good answers on how it winds up better than what we are currently doing.

My suspicion is that it wouldn't be any better, if you could even make it as good.  If a canard configuration had so much potential then you'd think that at some point in the last 80 years that people have been flying control line, people would have figured it out and started flying them.

Unless you can do as Howard suggested once in some other thread, and use active stability augmentation together with a rearward CG.  Even then -- nah.
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Online Brett Buck

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Re: Canardly Fly .
« Reply #30 on: January 21, 2015, 05:35:52 PM »
My suspicion is that it wouldn't be any better, if you could even make it as good.  If a canard configuration had so much potential then you'd think that at some point in the last 80 years that people have been flying control line, people would have figured it out and started flying them.

Unless you can do as Howard suggested once in some other thread, and use active stability augmentation together with a rearward CG.  Even then -- nah.

 Given the approach to date on just about everything else, it wouldn't surprise me to find that people missed something. I don't subscribe to the "if it was worth anything it would have been invented already" theory, particularly when most of stunt folklore is utter and complete nonsense.

   An example -  people had known about and fiddled with tuned pipes in stunt since the 60's (and I would have to check, but Wild Bill was talking about tuned pipes AND lower pitch props since before that). Until schneurle engines and the associated fantastic performance improvement, no one knew how to use it effectively. Everybody tried to boost the power and still run it at 8500 RPM. RC schneurle engines don't work worth a darn on a muffler. Bobby and company could only have figured out the *correct* way to use them after having attempted to tame schneurles on mufflers, then fly and an *RC Pattern Plane* with the engine set in an off-nominal way. And then be willing to actually try it.

  The fact that you or  I can't see how it would be an improvement (particular since the goal seems to be tighter cornering, which is not a limitation with the current airplanes anyway) could easily be just the way we are looking at it, and someone else can come along and figure it out.

   And in any case, thinking these problems through can be extremely helpful, even if it doesn't lead to a direct action.

   Brett

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Re: Canardly Fly .
« Reply #31 on: January 21, 2015, 05:42:17 PM »
Wouldn't that technically be a "rotating sphere?" 

   We are CL, so we look at the world in only two dimensions.

   Brett

Offline Balsa Butcher

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Re: Canardly Fly .
« Reply #32 on: January 21, 2015, 05:58:40 PM »
Guess ours was a little better than theirs...at least got off the ground more than once.  8)
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Offline Howard Rush

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Re: Canardly Fly .
« Reply #33 on: January 21, 2015, 06:29:47 PM »
Unless you can do as Howard suggested once in some other thread, and use active stability augmentation together with a rearward CG.  Even then -- nah.

Howard wouldn't have suggested this for control line models--not those to be flown in contests, anyhow.  Did he?  I hope not.
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Offline Tim Wescott

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Re: Canardly Fly .
« Reply #34 on: January 21, 2015, 07:21:25 PM »
Guess ours was a little better than theirs...at least got off the ground more than once.  8)

Yes, but cleaning the seat was such a chore for the ground crew, particularly after a foreplane stall event.
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Offline Tim Wescott

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Re: Canardly Fly .
« Reply #35 on: January 21, 2015, 07:40:46 PM »
Howard wouldn't have suggested this for control line models--not those to be flown in contests, anyhow.  Did he?  I hope not.

He may just have been commenting on the need for a higher lift coefficient on the foreplane to maintain stability.
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Offline Howard Rush

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Re: Canardly Fly .
« Reply #36 on: January 21, 2015, 08:09:58 PM »
He may just have been commenting on the need for a higher lift coefficient on the foreplane to maintain stability.

I don't think he'd have said that, either.
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Offline Tim Wescott

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Re: Canardly Fly .
« Reply #37 on: January 21, 2015, 08:31:29 PM »
I don't think he'd have said that, either.

It must not have been him, then.  Dangit, who said that?  (As far as I can tell, it seems to be true -- or at least I know from discussions about the various Rutan products that a canard needs a higher CL than the main wing.  It's why the Vari-this and Vari-that tend to have thick, cambered airfoils on the canard).
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Online Igor Burger

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Re: Canardly Fly .
« Reply #38 on: January 22, 2015, 10:14:40 AM »
What? again? Looks like canards need to be analyzed at least once yearly :- ))))

canard needs a higher CL than the main wing

that is clear and many times covered especially on SSW forum, but it is only about level flight, maneuvering in corners needs much more and situation is much worse

however that all are only guesses, it need to put 3 equation and solve them at once:

1/ we need lift in corner so we ned to count AoA, flaps and elevator deflection and airfoil properties and surface areas

2/ we need pitching moments, so we need lifts from surfaces as moments to AC plus surface airfoil momets plus CG moment

and all 3 AT ONCE

it makes relatively complicated situation, which will not allow simply decide that flaps on main surface will go down or up, we simply need to FIND where they must go to keep 1/ and 2/ conform. It will be immediately clear, that flap and elevator down to 30 degrees will make enough lift, but almost no pitching (so we cannot use that lift), and since CG is front of NP plus airfoil pitching moments, pitching will probably opposite then we need, so sooner or later we will find that rear surface needs smaller deflection than front surface ... clear solution will be to make wing smaller ... after several trials we will see that the optimal configuration is rear surface little over 25% of front surface :- ))) 

Offline Wolfgang Nieuwkamp

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Re: Canardly Fly .
« Reply #39 on: January 22, 2015, 11:57:28 AM »
This one, without flaps, made crisp corners. Elevator moved +/- 45 degrees.

Online Igor Burger

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Re: Canardly Fly .
« Reply #40 on: January 22, 2015, 12:03:36 PM »
:- )))

Also piece of paper will do crisp corner, question is how to do it with usefull (= heavy) wing load and with proper (= small) radius.

Offline Wolfgang Nieuwkamp

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Re: Canardly Fly .
« Reply #41 on: January 22, 2015, 01:21:24 PM »
As we all know, the smallest radius is  r=2*m /( CL* A * rho).

Without flaps, the maximum CL of the wing is lower because of missing flaps, but the canard gives additional lift.That helps to reduce the radius

Online Igor Burger

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Re: Canardly Fly .
« Reply #42 on: January 22, 2015, 01:50:00 PM »
If the foreplane gives more lift, simply do it larger, it will give even more lift ... guess where it leads :- ))

... do you know already what I wrote? :- )))

Offline Tim Wescott

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Re: Canardly Fly .
« Reply #43 on: January 22, 2015, 02:16:32 PM »
In my experience a reasonably-sized flapless stunter does corners that are plenty tight.  I'm pretty sure that the limit has more to do with induced drag than with actual gross lift.  So I'm not sure that dwelling on the whole "flaps give you the wrong turning moment" thing holds a lot of water.

If I had time I think I'd run out and build a few canard stunters, just to play with variations.
AMA 64232

The problem with electric is that once you get the smoke generator and sound system installed, the plane is too heavy.

Online Brett Buck

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Re: Canardly Fly .
« Reply #44 on: January 22, 2015, 07:21:41 PM »
As we all know, the smallest radius is  r=2*m /( CL* A * rho).

Without flaps, the maximum CL of the wing is lower because of missing flaps, but the canard gives additional lift.That helps to reduce the radius

     Igor had it right before!

    Besides, even entirely conventional airplanes with average wing loading will still turn, or at least appear to turn, tighter then the pilot can deal with anyway. I have never attempted to fly to the physical limits of any of my "regular" airplanes in terms of corner radius, at least not in competition.

     Getting it to start and stop the corners abruptly is also a limitation you will likely hit before you hit the wing loading/Cl limit. That,  I do work on and trim for. Paul Walker is the absolute master of that particular art, and I (we) learned a lot from watching and analyzing that.

     Brett

Online Brett Buck

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Re: Canardly Fly .
« Reply #45 on: January 29, 2015, 04:05:33 PM »
What? again? Looks like canards need to be analyzed at least once yearly :- ))))

   Next up for the winter "Hot Stove League", flying stabilizers.


    Brett

Offline Howard Rush

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Re: Canardly Fly .
« Reply #46 on: January 29, 2015, 04:21:23 PM »
   Next up for the winter "Hot Stove League", flying stabilizers.

Why not?
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Offline Tim Wescott

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Re: Canardly Fly .
« Reply #47 on: January 29, 2015, 05:10:17 PM »
AMA 64232

The problem with electric is that once you get the smoke generator and sound system installed, the plane is too heavy.

Offline Howard Rush

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Re: Canardly Fly .
« Reply #48 on: January 29, 2015, 06:02:04 PM »
With or without servo tabs?

I'd do it without.  You can hinge the thing wherever you want, so servo tabs would: a), do the same thing as hinging the stab a little farther aft, and 2) would have more separated flow, the avoidance of which is probably the best reason for the stabilator.  One could have the tabs go the other way: to wit, the same direction as the stab.  Some Piper airplanes do this. 
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Offline Serge_Krauss

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Re: Canardly Fly .
« Reply #49 on: January 29, 2015, 11:41:51 PM »
I'm all in favor of designing and building unconventional designs - whether or not they perform "better." I like to do that too. However, the fact that canards will not perform as well as aft-tailed aircraft, except under explicitly limited circumstances, is well documented in the aeronautical engineering literature and on this and the SSW forums. It's not just opinion.

SK


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