Final Misfit---- T-Bolt Asymmetric fin design (think C-141). Kevlar Failure

T-shaped fin, mounted on one side of the rocket. No angulation or trickery, just all aligned straight with long axis of rocket. Really nice flight.
I use Kevlar thread for my shock cord, I am losing my affinity for it. This was a burn through on the first flight. Better to be lucky than good, couldn't have happened to a better rocket. The T-fin on the one side oriented the rocket on descent PERFECTLY horizontal. Parachute came down with the nose cone, but the rocket body still had a beautiful and safe descent.
Didn't get a video or pad shots (I got adopted by 3 kids at the park and they weren't very patient for that stuff.)

Cool design but I am surprised that it would go straight up? Surely this would veer badly?

I launched the Estes MAV rocket with a missing foot and it veered badly.

It’s been a while since I launched this one. I know the net trajectory was straight. I can’t remember whether it corkscrewed or not, probably did. This is generally true of all my asymmetric fins rockets. Many of not most of them DO spiral or corkscrew, thus they are not alitude seekers.

I googled “veer” and got

change direction suddenly.
"an oil tanker that had veered off course"

I would interpret this as not only a CHANGE in direction but also a CONSISTENT and PERSISTENT change, I,e, it veered left and kept going that way,

For me, in Rocketry I would refer to veer or veering as similar to weathercocking or a rocket that starts out unstable does off vertical, then gets up enough speed and sets off either straight or in a non-vertical and gradually earthward arc. More importantly, both severe weathercocking or going unstable to nonvertical stable flights are potentially catastrophic to rocket itself, ground objects such as cars or houses or if hits ground while still motor burning, fire dangers, as well as potentially dangerous to spectators.

So “to veer” or “veering” has BAD implications.

“corkscrewing” on the other hand, is inefficient but cool.

Corkscrewing is viewed at least two ways. The purists will say that it’s a bad rocket, it isn’t flying straight and certainly is not flying efficiently. Sport flyers like me may just say, “hey, that’s cool, I like the spiral smoke trail, it popped at apogee and since it didn’t go as high as it would have if it was straight, I have shorter walk. So it’s all good!”

Bruce Levinson actually designed the one fin rocket

https://www.rocketryforum.com/attachments/levisoncork_screw-202-pdf.49300/
Which flies true to its name

I did the same with the Squirrel

https://www.rocketryforum.com/threads/squirrel.69006/
Many sounding rocket had some intentional rotation spin stabilization, I believe the idea was that if there were any asymmetries in forces they would average out as the rocket rotated.

Here’s a good example of what I feel is a very satisfactory non conventional flight


https://www.rocketryforum.com/threa...-the-mach-double-diamond.157128/#post-1955371

@BABAR,

But got me thinking about this is that I notice that these T fan rockets the outmost t-tops are smaller than the t-bottoms.

The jay hawk very much so!

I see 2 possibilities. 1) It doesn't matter in a cruciform design if the yaw fins are different sized than the pitch fins, as long as the pitch and yaw fins are same size. On the Estes MAV rocket, I lost a footpad and that made the rocket veer in a broad curvre

2) the farther the fin area is from the tube, the more leverage in corrective torque. This is the distance from the CG rather than the tube.

Key factor is alignment. T-fins or any orthogonal fin placed off center line of body tube will still work quite well, even if unbalanced (I'd say the T-bolt is an extreme example off unbalanced, but alignment was dead on.)

Any fin misalignment is bad, but effect IMO is greatly magnified if off center.