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Old Mar 16, 2008, 03:35 AM
who has rabbit ears down
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John!
I was offline during down/upgrading my net system, and wife had some worser than normal health issues going on, now things should(hopefully) be "normal"
Johnny
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Old Mar 16, 2008, 03:46 AM
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Johnny, I am very sorry to hear that. I wish her good health.

John.
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Old Mar 17, 2008, 03:23 AM
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Quote:
Originally Posted by John235
...
Are you still planning to build the Calypso with the flaps as designed?
...
Hello John,

no flaps are planned. The plane with the flaps was the Callisto. That will be several steps in the future.

Calypso is my "Entry-design" for Canards. Planned is a 3-piece wing with ailerons, twin-rudders and speed brakes. I just finished the ribs for the canard and the center part of the wing.
My 2nd choice for the motor was tested too. Graupner Power Gear 2,5 and Speed 500 BB Race. Looks good too.

Uli
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Old Mar 17, 2008, 08:03 PM
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Cap'n Canardly, I can't help but notice that beautiful canard avatar you have. Are there any more photo's or a build thread on it? Sorry, I'm just too lazy to look at all of your 650+ threads!
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Old Mar 17, 2008, 09:36 PM
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Canard Sailplane Build

The control system was added and tested. The motor was smooth, powerful and the folding prop assembly showed no signs of being out of balance. After adding the 1/16" sheeting to the top and bottom of the fuselage, there is no tendency for it to bend or twist. With the structure assembled less rudder, the battery balances the model when placed behind the wing's leading edge. Charles
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Old Mar 18, 2008, 02:23 AM
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48" Canard slope soarer layout.

Good to hear the gliders are progressing.

Tomorrow I will travel overseas and will be away for almost 4 weeks. When I get back I intend to start work on the slope soarer. The only unusual aspect of the design is that there is no canard elevator, so all control will be done using elevons and rudder. The forward wing is relatively small, but I don't expect any problems with pitch control authority because of the elevons on the main wing. Crow-braking will be done using inboard flaps to help make the descent on landing approach a bit more rapid and hopefully I can avoid hitting things. The attached image is a preview of the layout.
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Old Mar 18, 2008, 02:39 AM
who has rabbit ears down
Captain Canardly's Avatar
United States, MN, Buffalo
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agfrag!
My blog has info from last summer, and otherwise, there is "canardly soar" in the thermal part, and "Weird One's and other canards" in sailplane talk then there is the EDF Sailplanes in Ducted fans, which finally, I am making progress on. when I get the wing rods set, or even before as that is where progress is now, I can shoot those details if people need them, as my next step will be dihedral bracing and wing matching which I do slowly and accurately. I could use some input as to where the info goes, as I'm realizing even the gruops had a taste of my hectic lifestyle!
Johnny
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Old Mar 18, 2008, 11:13 AM
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Quote:
Originally Posted by John235
Good to hear the gliders are progressing.

Tomorrow I will travel overseas and will be away for almost 4 weeks. When I get back I intend to start work on the slope soarer. The only unusual aspect of the design is that there is no canard elevator, so all control will be done using elevons and rudder. The forward wing is relatively small, but I don't expect any problems with pitch control authority because of the elevons on the main wing. Crow-braking will be done using inboard flaps to help make the descent on landing approach a bit more rapid and hopefully I can avoid hitting things. The attached image is a preview of the layout.
Hi John,

so, the design itself looks more or less like a flying wing with an additional wing up front instead of an S-shaped-airfoil or sweep for balance. Looks interesting.

Your picture shows flaps. Do you intend to use them as flaps?
If so, how do you counterbalance the pitching moment. Flaps on a "normal" Canard-plane are a problem already. Here you would have to counter the pitching moment with the elevons (very short lever arm). Is that enough? This will be the "crow"-setting, I guess. Is there enough movement left then for aileron function?

Burt Rutan invented a "SpoilFlap" for the Solitaire (because of the Flap-problem). But I haven't seen a picture of that flap deployed. So I can only guess, how it looks like. It should work more or less pitch-free.

Or do you split functions: inside elevator / outside ailerons ?
But you wrote elevons, so it can't be.

I would expect (very) slow elevator response. A flying wing, which usually has elevons (or a Delta), needs only a low pitching moment to change pitch. With the stabilizing "wing" up front (long lever arm too), the necessary moment for a pitch change is much higher. The wing is not swept, so the pitching moment the elevons can do is not that big. It might be even less, then the "wing" in front can counteract.

I was thinking about a similar idea too. Basic desing as a flying wing with an additional elevator up front, but not "loaded" like a canard (no lift unless the elevator is used). But that idea needs some more time to think about.

I will be overseas too for 3 weeks from Monday on. So I am looking forward to your slope-glider design, when I am back.

Uli
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Old Mar 18, 2008, 11:31 AM
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John thanks for showing your new design. With the fair amount of coupling, I wonder how DOWN elevon will work? What incidence will you use up front? Charles
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Old Mar 18, 2008, 04:59 PM
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Quote:
Originally Posted by G_eronimo
Hi John,
so, the design itself looks more or less like a flying wing with an additional wing up front instead of an S-shaped-airfoil or sweep for balance. Looks interesting.
Yes, it has some similarity to planks/flying-wings, but hopefully avoids the compromises that you mentioned. It is a flying wing a canard stabiliser.
Quote:
Originally Posted by G_eronimo
Your picture shows flaps. Do you intend to use them as flaps?
The elevons are outboard and operate with both elevator and aileron control as you expect. The inboard flaps are mixed with elevator so the entire trailing edge moves up and down for pitch control. When crow-braking is used, the inboard flaps move down and the elevons move up. They will be setup so the pitching effects will be balanced when the crow-braking is applied. They do not work as flaps in the traditional sense, since they don't allow the model to fly any slower, just help to stop it flying when I need to aim for a small landing spot on the side of the slope.
Quote:
Originally Posted by G_eronimo
I would expect (very) slow elevator response. A flying wing, which usually has elevons (or a Delta), needs only a low pitching moment to change pitch. With the stabilizing "wing" up front (long lever arm too), the necessary moment for a pitch change is much higher. The wing is not swept, so the pitching moment the elevons can do is not that big. It might be even less, then the "wing" in front can counteract.
I don't know for sure how sensitive the elevator control will be. After thinking about the theory here, I decided to use short coupling to increase the effectiveness of the elevator control. If there isn't enough pitch control aurthority I hope it can be fixed by reducing the size of the canard stabiliser, or moving the stabiliser even closer to the main wing. I expect the pitch control to work 35% by change in pitching moment of the main wing airfoil, and 65% by change in lift co-efficient of the main wing, as both effects are in play when elevons are used with a canard layout.
Quote:
Originally Posted by G_eronimo
I was thinking about a similar idea too. Basic desing as a flying wing with an additional elevator up front, but not "loaded" like a canard (no lift unless the elevator is used). But that idea needs some more time to think about.
I think there may be problems with pitch stability, because the CG would probably end-up too far back relative to the neutral point. I hope you have a good trip. It is possible I will make some design revisions after 4 weeks away from it.
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Old Mar 18, 2008, 05:11 PM
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Charles, The canard will be initially setup with around 2.5 degrees decalage angle. The canard wing will use flat-bottomed airfoil which has more camber than what is used on the main wing. Even if there is not quite enough lift from the canard wing, the model should still achieve pitch stability when the elevons/flaps are reflexed upward. It remains to be seen how well it will work in practice.
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Old Mar 21, 2008, 09:58 PM
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Canard Sailplane Build

The canard wing was covered, Blenderm tape was applied on top and bottom and elevator gap covering tape was added. The wing was mounted and the control rod was fitted. Trim was added to the LE and TE center of the wing. Charles
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Old Mar 22, 2008, 09:56 AM
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I like it!
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Old Mar 22, 2008, 05:22 PM
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Thanks paulski, It is so much fun that I am dragging it out. The rudder is next and then covering and battery balance. Charles
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Old Mar 22, 2008, 11:12 PM
who has rabbit ears down
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United States, MN, Buffalo
Joined Jan 2007
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airfoil wars

Howdy Gang!
I was poking around, looking for a simplex airfoil coordinates, when I came across this point of discussion.I used the lift meter as a rule, as we want to know poundage more than anything-sorta
The program runs a Joukowski foil, and pic #4 shows the difference of zero camber to 1.5%(blue).
'Nuff said, just read the fine print- mostly in the camber and angle of Attack
johnny
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