IIRC, the only kind of truly odd-roc type of gliders I have tried were lifting body types. That was long long ago, 1970’s. They were hit and miss, and eventually I decided it was more fun to do models a bit more conventional since they would glide better, even if they were shuttle orbiters.
I will admit that 2 years ago I tried to modify the Quest HL-20, or sort of clone of the Centuri X-24 Bug, into something that would glide better. Or should I say.... glide period? Anyway, rather than the equilateral 3-sided rounded Tri-Oval “disk” that defines the cross section of the body shape, I made up a special disk that was more like a squashed oval (two “sided”, not a tri-oval). It was shaped so that by the time the body wrap went from perfectly round at the front, past the bulkhead, and then ended at the rear, the rear cross section was flat on top and bottom, with the outer edges rounded. That was to give it somewhat less drag, and more effective “wing” area. Heck, even more effective “wing”. Flew it, but it just would not glide. Maybe with enough flight-by-flight adjustment, and tweaking to give some more “up elevator” into the body, it could have been made to work, but I wasn’t interested in spending that much time to try to make it work.
EDIT - Added a drawing to show what I meant about the oval disk (orange) and the end cross section (yellow). The dihedral to try to glide came from the two fins as per the original HL-20 kit, at about 120 degrees from each other, like a 3-fin rocket with one fin missing.
One model I did not intend to glide, but did, was a certain carrier rocket for a flex-wing glider. The carrier rocket was meant to use a streamer for recovery. But, sometimes, the streamer ripped off. The carrier rocket would glide down tail-first in that case. I would not just glide down tail-first if used as a normal rocket, because it needed to be made to fly backwards into the airflow first. By ejecting out a flex-wing, the mass of the flex-wing was enough to cause the model to kick backwards at ejection and then glide.
As for gliding boosters, as in 2-stage rockets that have the booster glide rather than tumble, I’ve never been into those. Sometimes it is hard enough to find a booster after flight when you know where it should have tumbled down and landed in, but at least it is somewhat predictable (it has to be downwind of wherever it was over the ground when it staged, and the slower the tumble the more downwind it will be). By gliding, you would HAVE to watch it come down to have the best chance to find it (and what point is the glide if you do not watch the glide?), which means you can’t watch the upper stage.
So, a gliding booster is a sort of interesting trick, but due to the problem of watching where the gliding booster lands, or else a great risk of losing it, it just does not seem to be worth it.
Well, OK, there is one project I’ve done that has used a gliding booster allright (Though it did not ignite the upper stage by using a “booster” engine). But that is not the type you guys are discussing - something way different, and not an “odd-roc”.
- George Gassaway
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