Odd-Roc or Unusual Gliders?
My ever-growing interest in rocket-powered gliders is starting to run into my interest in unusual, out of left field designs (i. e., my taste for the bizarre ;) ), which has caused me to wonder about a sub-sub-genre that I am going to call "odd-roc gliders." These are rockets, parts of rockets, or add-ons to rockets that recover by gliding, but which do not resemble anyone's idea of a typical rocket-boosted glider. I am asking if anyone has ever designed one, flown one or seen one flown, or has any other knowledge of such beasts.
To give everyone an idea of what I am talking about, let me mention two designs (the only two that I currently know of) that would fit into this category. The first one was Centuri's Gliding Booster, used primarily in the Black Widow two-stage kit, but also sold as a stand-alone add-on kit. Although the primary purpose of this item was to act as a booster stage in multi-stage models, the fact that it supposedly recovered by gliding, rather than the more typical tumble recovery, made it, in fact, a boost glider. Does anyone have any experience with the Gliding Booster? Did it actually glide? How difficult was it to trim for gliding?
The second design that I know of that qualifies as an odd-roc glider is Larry Deran's 1968 MRN plan, The Flyin' Stovepipe. This appears to have been a completely original, totally radical, absolutely unglider-like glider design that must have broken every rule in the book, and yet it worked. Or did it? Does anyone have any experience building this design (I don't - yet) and flying it, or seeing the flights of someone else's build, including the designer's own model? How well did it work? What was the flight like? I am absolutely taken by the bold daring of this design.
So you see what I'm after. In the 50 years of model rocketry, surely some other unglider-like gliders have been designed and flown besides these two; at least, I hope so. I'd love to have you tell me about them, any that you know of. And if you happen to have plans, picture or links to resources, well... that would really be the icing on the cake. And they don't have to be all successes, either; I'm also interested in hearing about designs that may not have quite worked out. So how about it? What wants to start? :D
Another boost-glider type (odd by today's standards) that came and went pretty quickly in the 1960s was the Mini-Bird, which was developed by a model rocketeer named Ward Conley. Like many rear-motor B/Gs and some front-motor B/Gs, it ejected its motor.
To envision what a Mini-Bird looked like: Imagine a scaled-down Estes Astron Alpha made using BT-20 or BT-30 tubing, with the body tube cut off just ahead of the fins and with the nose cone glued into the end of the much-shortened body tube. One of the three fins is lengthened in span by an inch or so, and being slightly heavier than the others it hangs down vertically as a vertical stabilizer (a ventral fin) during the glide, while the other two fins serve as wings. The Mini-Bird was sort of an upside-down version of the Centuri Black Widow's gliding booster.
Using a streamer-recovered 13 mm motor adapter mount (or such an 18 mm mount in a BT-50 or #10 tubing size Mini-Bird), this design would be "NAR-kosher" for competition. While it isn't a very good glider, getting as much "hang time" as possible out of its stubby fin/wings would be an interesting challenge, and the rear-ejecting motor mount would make tangled-up-streamer-and-glider "Red Baron" DQ'ed descents very rare if not non-existent.
I don't want to start an argument with you about what you said about Ward Conley's Mini-bird, but according to G.Harry Stine's description of it in his 1965 Handbook of Model Rocketry and earlier description of it in an American Modeler magazine article, I believe that some of your information may be incorrect.
For example, all 3 fins to the best of my knowledge were the same size. The Centuri Black Widow Booster and the Free Estes Plan Tiger Shark both used gliding boosters that had one or two fins larger than the others.
The Mini-Bird had "wedges" on one side of each fin resulting in a spinning motion during boost and a rolling, coning motion much like the Flyin Stovepipe.
G Hary Stine, thusly says, " After many model rocketeers had seen lower stage booster bodies glide back to earth rather than flutter, it became obvious that a gliding booster configuartion could be converted into a B/G.
Paul Hans was the first to do this, in 1962. His Aeolus design, in Figure 9-16 , was a ballistic rocket adapted to glide,
Ward Conley, of White Plains, New York, brought simplicity to this "minibird" B/G variety by eliminating elevons altogether, balancing for proper CG-CP during powered-boost phase and for proper trim during the glide phase, after engine ejection."
The drawing of the Min-Bird looks to me like 2 of the 3 fins were slightly larger than the 3rd; i.e. 2 wing fins and a smaller rudder fin. It may be just the perspective of the drawing.
G. Harry Went on to say this about the Min-Bird in a 1964 article, "Ward also used spinnerons, actually, wedge spoilers-on each wing-fin trailing edge so that his bird corkscrews up and glides back in graceful slow rolls. "
Perhaps the original 1962-ish Mini-Bird didn't have these wedge spinnerons on them; maybe they were a later addition, I can't tell by the context in which G. Harry is speaking.
I've also thought the Mini-Bird worked like the Flyin Stovepipe: spin on boost and a slow rolling motion on glide. I could be wrong.
I created a Flyin Stovepipe glider a few years back and although I never flew it, I did test glide the "tube"..... I also did some extensive background research into its aerodynamics especially patent searches. During the test glides, you will get a sort of corkscrew effect.
I'm attaching a few drawings/pics of Paul Hans Aeolus.
The only Mini-Bird drawing I ever saw showed what I described above, which does not preclude other design iterations having been developed before or after the design I saw.
Your Number 1 and Number 3 images above have been giving me a "brain itch" all evening, and now I remember why. Some years ago I had a catalog from a German company called Modell-Bauplane, which sold plans sets for all kinds of flying models, literally from airplanes to zeppelins!
They had very little in the way of model rocket plans, but I remember one boost-glider plans assortment that they offered. It included plans for a Rogallo flex-wing, the Estes Falcon (or the very similar AMROCS Hawk--it was hard to tell from the photograph), and another boost-glider that looked just like Paul Hans' design in your attached photographs above. At the time I thought it was some obscure European design that they had included in the plans assortment, perhaps so that their European customers wouldn't grumble about only American designs being in the assortment.
Hmm... that second picture with the various BG models is really interesting. I love the lines of both the Renger and the Variable Geometry models. The wings on the Renger look really sharp, while that tail on the Variable is cool. Looks like I've got a couple new designs to play with. :D
"OH, oh I'm sorry, but this is abuse.
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Q: Ah yes, you want room 12A, Just along the corridor."
well, how else should I phrase it. I recognize the fact that BalckShire saw what he saw and I accept that as true; I just posted how GHS wrote about what he saw. Its entirely possible taht both BlackShires memories and GHS writings are both true as the Mini-bird could very well have undergone several iterations at various times in its history.
And I hate to say this, but it is true, GHS mis-reported a number of things several times in his writings; things that just don't make any sense, when you talk to other people who were there. I attribute this sorely to memory laspes like i have sometimes when I try to provide historical info and I post from memory instead of digging out the proper documents and paraphrasing from them. I strive to be as accurate as I can be and I also have striven to actually contact these people and get their own "memories" of events.
One thing I found is a lot of people we (well perhaps only me) look up to in the modle rocketry hobby from days gone past, they really didn't think too much about their contributions of their places in modle rocketry history.
Most had moved on to bigger and better stuff in their lifes and careers and their view of their roles in model rocketry were often considered minor in their own minds.
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
Do things like the Infinite Loop and backsliders count as odd-roc BGs?
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