Aerodynamics question

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hcmbanjo

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How much nose weight would you recommend for the 18mm Corkscrew variety?
It shouldn't need any nose weight.
You've got to find the right length body tube to get the corkscrew.
Go too long with the body tube (or add nose weight) and the rocket will fly more stable,
without corkscrewing.
 

DrewW

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It shouldn't need any nose weight.
You've got to find the right length body tube to get the corkscrew.
Go too long with the body tube (or add nose weight) and the rocket will fly more stable,
without corkscrewing.
Excellent! Then I should be ready to roll for next weeks club launch with a 13mm and 18mm version.
 

BABAR

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Please post your flight results thanks
 

DrewW

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@BABAR
Flight #1 of "A Little Tipsy" (13mm version) went off with video a few weeks back at the last club launch. I think I need to reduce its static stability to enhance the corkscrewing. I don't quite keep up with the rocket, but the smoke trail tells the story. Straight and fast off the rod with a transition to corkscrewing.

18mm version went off a little better and on a quest black max motor, wasn't prepared with my phone when it lit off, but about the same behavior. Obviously way cooler with black smoke though.

 

BABAR

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@BABAR
Flight #1 of "A Little Tipsy" (13mm version) went off with video a few weeks back at the last club launch. I think I need to reduce its static stability to enhance the corkscrewing. I don't quite keep up with the rocket, but the smoke trail tells the story. Straight and fast off the rod with a transition to corkscrewing.

18mm version went off a little better and on a quest black max motor, wasn't prepared with my phone when it lit off, but about the same behavior. Obviously way cooler with black smoke though.

View attachment 464150
Looked like a successful flight. Since I am not shy about asking, would like a pic of the rocket itself. (or both, side by side)

Definitely had some corkscrewing! Whether the degree of corkscrewing was just right, too much, or too little is all up to you!

The classic single ring attached to one side is also relatively durable on RECOVERY, as when the rocket falls it pretty much always falls with the ring UP, to the part that hits the ground first is pretty much always the motor casing or at least the body tube opposite the ring. So long as the forces don't rip the ring off the bird (certainly a high stress joint on boost), even with a small streamer it tends to recovery nicely.

Congrats!

Check out Devil's Triangle in the Scratch section if you want to see another recent "skwewy" rocket.
 

DrewW

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Looked like a successful flight. Since I am not shy about asking, would like a pic of the rocket itself. (or both, side by side)
Side by side below, will definitely give a try to devil's triangle sometime!

corkscrews.JPG
 
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