Another Crack at "Finless" Bullet Bill

[lakeroadster]

Spin wouldn't help. A real bullet spins at 30,000rpm to get some stability.

Spin indeed helps with stability...

https://en.wikipedia.org/wiki/Spin_stabilization
The second stage of the Jupiter C used spin stabilization. Designed by Wernher von Braun in 1956 for his proposed Project Orbiter, the Jupiter-C obviated the need for a guidance system in the upper stages

 

[KenECoyote]

Spin wouldn't help. A real bullet spins at 30,000rpm to get some stability.

From my finless rocket testing years ago, spin does help.

 

[BigMacDaddy]

I have a section of 5.38" LOC tube coming in and I am scaling the model for that style tube as well.

Should I revisit the angled internal fins to help spin the model?

Also, @Charles_McG I was looking back at your prior comments in other threads about GDS. Your idea of an internal airfoil in the induction tube is interesting and might be possible (with some limitations - i.e., could only do a relatively short distance in the top of the tube) since I 3D print a front edge support ring for the tail portion. Did you ever try this or come up with any design ideas?

 

[Charles_McG]

Also, @Charles_McG I was looking back at your prior comments in other threads about GDS. Your idea of an internal airfoil in the induction tube is interesting and might be possible (with some limitations - i.e., could only do a relatively short distance in the top of the tube) since I 3D print a front edge support ring for the tail portion. Did you ever try this or come up with any design ideas?

I haven't worked on it - I got distracted by 2 stagers. For several years now.

 

[Charles_McG]

I haven't worked on it - I got distracted by 2 stagers. For several years now.

I'm going amend this statement - I do have a crazy idea on the drawing board, but flying ring / zylo related. Flying rings work better with a simple inner structure at the leading edge. Or maybe just a turbulator. I'm curious about trying printed rings with an inner surface airfoil to amplify the thru-airflow, Dyson fan style.

But the crazy idea I really want to try is a Blender like model with hinged, tensioned blades so that the rotation of the model on ascent lifts the blades up and out so they interlock into a ring. So the model transforms from high base drag saucer to flying ring - and then back again as it slows at apogee.