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Old Apr 28, 2015, 07:28 PM
Robert4613 is offline
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Is it spring yet?
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After a time of being offline I've started a new project......again.

Ever since I lost my job I no longer have a computer to work with, and a cell phone is a bit challenging to type on. I've built a few DTF birds, and unfortunately terra firma has a knack of jumping up at them, except two, which I have yet to finish.

Just a few days ago, after a few dsys of planning I've started on a sport type plane. I'm still in the planning stages but I've fine tuned the building process. It has a 30" WS with a 20" fuse. I'll post more details as I go wirh the build. It should be interesting to see how it turns out. Below is a couple of teaser shots.
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Old Apr 28, 2015, 07:55 PM
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If it is not glued yet, I would make the horizontal a bit larger? At least to the front of the
vertical.
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Old Apr 28, 2015, 08:49 PM
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My plans are in my blog
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This had a short moment about it. The rear wing and tail ought to be a bit bigger. Or perhaps add a few inches to the fuselage.

No doubt you can make it fly, do good luck on the eventual maiden. The ground is eager to jump up at it, so have fun anyway.
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Old May 03, 2015, 12:42 AM
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I've taken into consideration of a few things, and one of them was to shorten the wing by 3" to get a little closer ratio of wing and fuse. I've also begun planning out the placement of all of the electronics, after I had determined thr approximate CG. During some testing i had discovered that there was a bad hxt900 servo, so I had borrowed an ar6060 from my H&M Corsair, but the servo is at least three times larger, and definitely heavier than my 9 gram servos. Once I bad everything temporarily secured I performed a test glide, and the initial glide test proved to be promising. I had designed the battery to be able to move fore or aft to obtain proper CG once i get to that point.
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Old May 03, 2015, 04:22 AM
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Sorry to hear about the job loss, etc.

Look up "tail volume" (it's a technical term and has a very specific mathematical definition) and what its typically acceptable values are for model aircraft.
I doubt your current configuration (the one in the pics) is within the "comfortable" range - for such a short-coupled design, a larger tail is almost certainly in order here.

Regarding CG: This is a "conventional" design (nothing exceedingly out of the ordinary), so you should be able to use the CG calculator to get the "right" CG location - Here's the link: http://adamone.rchomepage.com/cg_calc.htm
Basically, you're shooting for 25% of mean aerodynamic chord.
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Old May 03, 2015, 09:29 PM
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Luckily this was just cheap $1.00 foam. This one, like the other half dozen attempts prior, was also a failure. I've decreased wing size to be in proportion with the fuse, increased H stab size accordingly, ran not one, not two, but a few various CG programs, and kept the plane within the parameters of the electronics that I had on hand, (which were designed for the Polaris, which was another failure), and it still took a flying dirt nap. No, no video, the kid that I had running the video couldn't operate a simple cell phone video app.

Back to the drawing board.
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Old May 04, 2015, 01:09 AM
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I've consistently found that scaling up a 30 inch plane by a factor of 1.5 or 2 greatly improves the plane's handling, regardless of its particulars. Most notably, typically the wing loading goes down dramatically and the Reynolds number goes up significantly - these two factors combining to make the plane much more well behaved.
Depending on your skill level, this can make the difference between utter failure and resounding success.
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Old May 10, 2015, 12:12 AM
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Sorry for not posting on here as soon as I could have, I had forgotten to get my email changed, thus wasn't receiving new post notifications.

Yes, I'm still new to this so I'm still having a hard time building a successful flyer, but I'm still refusing to give up. Lately I've been searching online for general and specific airplane proportions, as well as desing a bird that will work with the components that I have on hand without having to go out and purchase more. I'll take any and all advice that I get, and hopefully understand it enough to hopefully guarantee a successful flight on my next bird. Thanks to everyone for their input, and if you have more to add, feel free to drop in and post it, I'll be looking forward to reading them
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Old May 10, 2015, 02:19 AM
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Hi Robert,

Give us a sense of your experience level as a scratch builder and your experience level as an RC pilot.
Also, might you consider building someone else's design? There are dozens of very easy to build and fly planes (look up "simple delta" or "ez-fly" for just a couple of options).
Starting out with someone else's design to get the build skills sharpened is usually a good approach.
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Old May 10, 2015, 01:12 PM
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Nuteman, I've built the Polaris and a Dirt Simple Delta, both of which didn't turn out too well. The Delta was too tail heavy, it bobbed kike a dolphin, and crashed breaking the prop, and the Polaris never had a chance to make it off of my work table due to a construction oversight. I'm also thinking that part of my problem is not being able to match my components to the airframe, but one of these times I'll finally have a working setup. (Fingers crossed).
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