@Dotini , I want to thank you for getting me on this track. I can't compete with you on Magnus. This DID however divert me back to BackSlider recovery, and I think I am about as pleased with this as I was with the Gyskelion in 2011
https://www.rocketryforum.com/threads/gyskelion-helicopter-rocket.25862/ jump to post 11 for the flight and practical details, if you don't want to click the links on post 1
I remember reading about Back Slider rockets, I think in Tim Van Milligan's book, where I also read about horizontal spin and Magnus recoveries and Air Brake recovery. Interesting thing was that I don't know if ANY commercial kits used these techniques, and could find very little on the Rocketry Forum or online about them. The articles on BackSlide made it sound pretty hard to do, requiring a 30 to 1 length to caliber ratio and small fins. And I did try it a few weeks ago, it worked great but one of the fins broke off, pretty much to be expected the way this glides in for a landing. Then I thought about some of my asymmetric fin models, and some of my models which had streamers or chutes and recovered with the nose cone hanging off the chute and the body of the rocket just kind of falling horizontal next to it, since the drag of the fins was enough to balance the rocket even with the motor weight in the tail. I had launched rockets which had NO fins at all on one side of the rocket, I will have to submit one to
@Neil and play with it in Open Rocket (had it and RockSim for years, never used them.) But I haven't seen and kits or even any scratchers on the forum that had ZERO fin surface on one side of the rocket (exception,
@Flyfalcons 2 fin Guitar rocket, THAT was mega cool, posted at end here for those interested*, you know those guys that are just really nice and really bright and really talented and can make rockets that are both engineering marvels and works of art? yeah, those guys you just want to hate and can't because they are so darn good. Yeah, he's one of them)
Anyway, this one came out just the way I wanted to. No, it's not art, my excuse here (although the real reason is I lack to the patience for good finishing skills) is keeping the weight down, so all the color is with markers. The Asymmetric fin design WORKS. Yeah, there's a little corkscrew action (not sure if that reduced weathercocking or not), but net trajectories are STRAIGHT. At apogee, the ejection charge vents out the side ports just behind the nose cone and kicks it off a normal stable trajectory, it goes into freefall. At that point, Barrowman, RockSim, and OpenRocket all go out the window. At this point I am not sure what happens, but it DOES happen consistently, the rocket's heaviest part is the tail (makes sense, that's where the motor is and all the fin weight), it comes down that way first, but the fins cause enough drag to keep it level. And because the fins are predominantly on the DORSAL side of the rocket, it tends to come down dorsal side up. Since there are NO fins on the ventral side of the rocket, the rocket lands either on the motor casing or the ventral body tube, neither of which is prone to breaking. Had four great flights, rare for me to fly a rocket at one outing more than twice, this one was just so much fun.
Can't beat the prep. Remove old motor. Stick in new motor. Tape around the end of the motor mount and the protruding end of the motor. Install an igniter and go.
No chute, No streamer. No wadding. No burn string. No rubber bands. This rocket has NO moving parts, even the motor stays right where it is. The only thing that moves is the ejected propellent and the rocket as a whole.
Here's the pics..
here is the best flight, although I am not the best videographer, you can see it at the lower 1/4 of the screen at 38-40 seconds. By the way, the corkscrewing portions of the flight are ABSOLUTELY expected with this design, I have decided that while they cost me a bit in altitude (which is not my goal anyway) they are part of the "devilish" cool factor in these rockets. At least on the boost phase, these are NOT on the "straight and narrow" pathway (sorry
@Peartree ), although the descent is surprisingly straight.
few more flights
Here you will see it again at 38-40 seconds, just below 1/2 down on the screen and just to the left of mid screen.
I used the same tube for my Magnus and AntiMagnus rockets, the Magnus flight was weird, I will post that later, but it did put a crimp in the tube that I was sharing between rocket fin cans. After the AntiMagnus had an unstable flight, I wasn't sure whether it was due to the repair crimp (which may have had a bit of a bend to it) so I just cut off the crimped tail end, crossed my fingers and hoped the Devil's Triangle would still be both STABLE on ascent with the shorter tube and BACKWARDLY STABLE on descent, again with the shorter tube. Peter Always discussion made it seem like CG was of critical importance, I am NOT sure that is really true. In any case, it worked just fine with a couple inches cut off, so experimentation will have to go on with how short I can build these. Anyway, elected to go with a C6-5. Wondered if it would cause stability issues. Was NOT a problem, net trajectory was an Arrow Straight vertical boost (okay, the rocket corkscrewed AROUND that net trajectory) but I was plenty happy with the altitude I got. Unfortunately I lost it in the sun after seeing it establish a horizontal glide. I went looking for it (I had started the launch at one end of the park, unfortunately for me apparently a youth soccer group was out of school this day and took over my area of the field, so I moved a few fields down. The glide was HEADED toward their end of the field. As I was walking that way, a gentleman waved at me and pointed me in a different direction. I went ahead and spoke to him and he pointed out my rocket two fields away, it was 90 degrees from where I expected it to go, but I found it!
This shows a great launch, with straight portions and corkscrewing, don't bother to watch after that, I lost it in the sun.
*
build thread here
https://www.rocketryforum.com/threa...ll-flying-v-guitar.134436/page-6#post-2039558