What am I building?

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Well-Known Member
Jan 4, 2009
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Seriously, this is my doofus moment. :eek: I bought parts right before TRF 1.0 went down, based off of another person's build thread. And now I can't remember what kit I was trying to replicate. :confused:

Can someone figure out what kit these parts make up? I believe it's an upscale of some Centauri (duh) boost glider, but I could be wrong. It could be a standard kit/upscale. I've searched both EMRR and Jimz but, can't find it. Dooh!!!

Parts are from Semroc.

FV-3 Centauri Laser-Cut Fin Set
BC-20045 Balsa Nose Cone #200 4.5" Elliptical
CR-KV-3 Centauri Ring Set

P.S. As embarrasing as it is, yup, I've sent an e-mail off to Carl and Sheryl
Can you take a picture of the "Centuri" fin sheet and maybe we could take a stab at it? ("stab" was not meant to be a boost glider pun...)
That be the one!

Carl (Semroc) also responded with it as well. So I've printed the plans off and am going forward from there.

Maybe you had previously read the old "Coaster" thread on YORF, about that model (The Centauri Dyna-Soar glider plans from Coaster). If you did, you may want to refresh your memory. Also, there was more discussion on it a few weeks ago. And if you never saw it, you definitely need to:


This seems to be the sort of thing to try to make fly successfully despite itself. And unless it is built as heavy as a tank, no need to test fly it first on anything over a D12, because if it will not fly straight/stable on a D12, it's not going to fly on an F. And a model that size is not really big enough to justify an F. Sorta like doing the old Estes SkyDart on a D12, and trying the first flight ever on a D12 instead of a B6.

Keep in mind this was designed just 1-2 years after the first successful B/G's, and that does not mean that whoever designed THIS had a lot of successful B/G experience.

If I was doing this, I'd do it one of two ways. If I did not care how it looked, and was not going to have a lot of $ invested in it, I'd just push ahead and quickly get it built and try it out (what point is there in spending a lot of time on the finish and appearance, if it craters itself on flight #1?).

If I wanted to make it look nice, or simply improve the chances of it working out right, I'd build a small model of it based on BT-50 (50% scale), and build it in just a few hours one night. Then try out the scale model of it, on a B6-2. If that went well, then maybe also try a C6, if it was not likely to fly away. Take what I learned, and make sure the larger (real) model had the good proven aspects from the test model (including the liftoff CG not being more aft than on the model, percent-wise), and also improving/fixing whatever was not so good on the small test model. Maybe the model would want to pitch badly nose up or nose down, so you'd need to make the model ROLL on the way up (probably a good plan regardless). But I only mention a test model as something to do really quick and simple. Not as something to put a lot of time into, to the point that you spend almost as much time on the test model as you would on the real model later, which defeats the purpose of the idea (some otherwise might spend so much time obsessing over "getting it right" with the real model that they could have saved a lot of time by building a small test model and flying it).

I have done that sort of thing for various projects, either a 100% size boilerplate or a sub-scale test model. Attached below is a photo of a 1/3 scale model of the Orbital SkyDart Project, for example. Thrown together in a night, thanks to CA. Worked out well, and actually the BT-50 winged booster became a nice sport glider to fly.

Even at that, once the real bird was built.... I'd wait on doing the final paint and any decals (?) until after a first test flight.

Normally on a proven model, like, again, the Sky Dart, one can tackle the project without being so concerned that it will fly right. But the more I have seen and heard of this design, the more I wonder how successful it ever was. See the video of the Free Flight version that was test flown on an F, as included in the YORF thread.

- George Gassaway