New Design -- Freewind BG
 

Here's a glider design that I'm trying to morph into a pop-pod BG. The glider should fly as shown, with the CG at about 25%. The ballast weight is about 1/8th ounce, or one good ball-shaped fishing sinker. I'm going to build a couple of these to see if I can trim it for a good glide, then I'll work on the pod.

Notice on the 2D views the working margin value of 8769.28... RockSim says it's overstable. :D

Wingspan: 13.5"
Length: 12"
Weight: 0.472 oz

Enjoy!

I really like the look of this one, Craig.

Thanks!

I wish I knew more about BGs than I do. There's both an art and a science to them, unfortunately I'm neither an artist nor a scientist... :p

Yeah, you and me both. And I don't generally have either the time or the inclination to spend much time trying to refine things until they work right.

The one rule of thumb that I've always used is to have some stability inducing part of the glider be on both sides of the motor thrust line. I've done this by having the vertical stab under the fuse and the wingtips above the thrust line via dihedral. That said, I do like the looks of the glider.

Kevin,

Behold... The Freewind BG Mk II...

Is this something of what you had in mind? I know the wing tips are not quite where you're describing, but I may have another idea for that... :D

Yet another version...
 

Here's the Mk III version, with polyhedral tips. The span is now 17".

I can't really tell much difference between 1 & 2, but they both look pretty good. I think what Kevin was really talking about was turning the tail upside down so the vertical control surfaces (rudder) are opposite the boost pod. Also, how many degrees of dihedral do you have there. Rule of thumb is that a dihedral of 15 degrees works about the best, and the dihedral should be wrapped around the boost pod (like you've done). Personally, I like simple dihedral such as you have in versions 1 and 2, and I find complex dihedral as in 3 a bit tedious. Again, the total dihedral should be about 15 degrees.

Greg

For the Mk III version, the main wing panels are set for 10 degrees total (+ & - 85 degrees), and the polyhedral tips are at 90 degrees to each other. The stabilizer is set at 30 degrees (+ and - 75 degrees), and the rudders are at true 0 degrees.

The only difference between I and II was the location of the stabilizer attachment, and the shaping of the boom. The wing remained the same. There was no difference in the dihedral between any of the three.

As soon as I get some "housework" done (reconstruction of a wall in my computer room) I'm going to build one of each to see how they fly. I'm starting to get itchy fingers for this project... :D

More dihedral, man. More dihedral.