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Old Jan 30, 2013, 10:17 PM
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Hey thanks Chrizz! That video helped a lot. I thought I understood how it needed to be setup, but I was starting to get a headache thinking about it
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Old Jan 31, 2013, 09:44 AM
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United States, OH, Bradford
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falcn, the principle behind all of this is that an airplane in flight acts like it's mounted on a ball joint located at the C/G. Control surfaces in front of the C/G have the opposite effect of what happens if they are behind the C/G.

So, if you have a conventional aft-tail with elevators, deflecting those elevators upwards pushes the tail DOWN. The plane pivots around the C/G, so pushing the tail down makes the nose go UP.

If those same elevators are mounted on the nose (a canard), in front of the C/G, then deflecting the elevators upwards pushes the nose DOWN, so you get a DOWN elevator command, the opposite of what happens with the elevators on the tail.

So, to figure it out, find the C/G, note where the control surface in question is relative to the C/G, and then note which way the plane will pivot around the C/G when you deflect that control surface.
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Old Jan 31, 2013, 11:46 AM
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United States, MI, Honor
Joined Dec 2005
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Check this one out everyone.

http://www.rcgroups.com/forums/showthread.php?t=1821567

I wonder how it will fly. Looks fast to me.
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Old Jan 31, 2013, 08:33 PM
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Don, It's good to hear from you and hope you are well.

Conehead, Thanks for the link to the unusual sailplane canard.

Charles
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Old Feb 01, 2013, 06:45 PM
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Thanks for the lesson Don. I think I have my brain wrapped around the concept now. I thought that was the way it worked, but the longer I thought about it the more confused i made myself . Now if I can just maiden that Tristar without crashing and burning!
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Old Feb 01, 2013, 08:49 PM
Lighting Up the Darkness
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Joined Jan 2013
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GWS canard conversion

With all of the engineering marvels you guys come up with, my little GWS project pales in comparison. None the less, progress continues. Even though this is a slow stick conversion, I'm not so sure it's going to be all that slow. I know I've overpowered it a bit, and there will be more weight to it than what I'd like, but I'm feeling pretty confident about it so far. While running up the motor I noticed the torque is significant, very significant. Hopefully with the installation of the main wing and the canard, add in some airspeed, and hopefully it will be OK (but I can already tell that I will have to go easy on the throttle).

The main wing is ready and braced up extra good. The little video camera bracket (and camera) is installed, and I added a power switch (I got spoiled on those old jetis that all came with a switch!). I did not have any wheel collars to keep the wheels on, so I dug around for an alternative. I ended up using a one way type of washer (they splade out when you push them onto the landing wire, and it's a one-way-only installation - not sure what they are called) but seems to be a very good solution (in addition to a little tape, a dap of canopy glue, and the sexy plastic hub cap that was in the kit. The stock landing gear could not support the weight, even without the main wing installed. So, I went with a very small wire from one side to the other. This seems to have added the necessary strength....but the proof of it all will be the first flight of course. I intend to add some LEDs just to keep it interesting (of course it really doesn't get more interesting than a canard) but why not light it up. The last task will be figuring out the actual canard. Thanks for letting me share....
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Old Feb 01, 2013, 09:13 PM
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nightlightrepair, That looks like very excellent work. I feel sure that your design will carry the extra weight. You will have plenty of lifting area with added inertia to help on maintaining a penetrating attack.

Charles
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Old Feb 02, 2013, 09:32 AM
Lighting Up the Darkness
United States, GA, Loganville
Joined Jan 2013
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Close to completion

Thank you Charles. I'm going to get an accurate total weight when completed. I'm so appreciative that you have already done all the calculations regarding the AOA and the surface area of the canard, as well as the CG location. What I love about your design here is the fact that you can easily manipulate the heaviest component (the battery) to dial in the correct CG preflight each time, depending on the optional equipment load (camera and such). That's why I think this platform will be outstanding for arial photography. Pushing the envelope on weight, I just hope that "penetrating attack" you speak of is through the AIR and not into the GROUND! (either way, it'll make for an interesting video!)

Russ
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Old Feb 04, 2013, 02:28 PM
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Russ, I believe you said you have added extra power to the Slow Stick which should move it out fast. I cannot imagine it not flying well with your expertise and past experience. It would be great to see the aerial photography.

Charles
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Old Feb 04, 2013, 03:35 PM
Lighting Up the Darkness
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You can bet I will post the maiden flight video. Should be fun! So stay tuned
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Old Feb 04, 2013, 05:08 PM
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We won't hold our breaths, but we wait for the video and will watch it in full.

Conehead
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Old Feb 05, 2013, 07:07 AM
What could possibly go wrong?
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Joined Apr 2006
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1/4 scale Long EZ

About 12 months ago I had one of my most spectacular failures - this 92" Starship It flew, but I couldn't get any roll control. It had ailerons, not elevons, and plenty of travel, but I couldn't steer it successfully and, on the second flight, we wiped out and spread a lot of depron over the next field. Probably I didn't take enough of the good advice I got from Don to be sure that the structure was rigid. I couldn't think of any other explanation.

So, what's the right thing to do with a smashed-up very big Starship? Make it wait in the barn for a year and then take the best bits and make a very big Long EZ. I've used the outboard wing panels, adjusted them a little and this time I plan to cover them with glass cloth and Water Based Polyurethane.

What could possibly go wrong?
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Old Feb 05, 2013, 09:59 PM
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United States, WA, Kirkland
Joined Sep 2010
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That Starship is foam? Wow. I saw a Starship at a museum once. Good lookin' bird!
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Old Feb 06, 2013, 12:33 AM
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Tick Point's Avatar
Joined Mar 2008
540 Posts
12 months ago......

I see the fins have rudders, and they were splayed outward.
Could that have stressed the wings in flight and prevent aileron movement?

Great attempt! Good salvage too!

Dave
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Old Feb 06, 2013, 04:46 AM
What could possibly go wrong?
nickchud's Avatar
Market Harborough
Joined Apr 2006
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Starship! such a beautiful plane!

I've been a fan since 2009 when I came to this site for help in a scratch build. I even met Bob Scherer, who keeps one of the last ones flying. It's based at Orange County, John Wayne Airport,CA. Here's a link to my 4 ft ws foam version. It includes plans, pictures and some interesting links to Burt Rutan, Bob Scherer and others.

You're right about the rudders on my 92" version. What I was trying to do was to mimic the full size plane by having them move only in one direction - outwards on the inside wingtip The result was that they were fairly sloppy close to neutral, they didn't return precisely to that position. I didn't think it would cause a problem but, sure enough, something went wrong. My theory is that, the more aileron travel I transmitted, the more the wing would warp the wrong way.

I did get some successful turns, slow ones. On a fairly windy day, it was just not responding fast enough. :
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