I just created a new simulation file of the Andromeda, with the addition of two CR-713 centering rings mounted at the openings of the shrouds. This will block off the flow of air through the shrouds and prevent them from acting as ringfins. The first indication that this may be important is the altitude gained: 910' versus 881' over the non-plugged non-ringfin simulation. The second indication that something changed was the stability margin; when using a C6-5 the margin dropped to 0.74. A ballast weight of 0.10 oz was added to the back of the nose cone, and the margin came back up to 1.13.

The fins were altered to allow the shrouds to fit better, and a slot was drawn in to allow for the two centering rings. A corresponding interlocking slot needs to be cut into both rings.

I'll work up the latest patterns and post them later tonight, or tomorrow.

__________________
Craig McGraw

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SAM 0044
AMA 352635

Craig said,


This leads me to suspect that just maybe Rocksim is not accounting for airflow through both the Ringfins and Tubefins. I wonder?? It may be the extra wieght of the added CR-713 that accounts for the altitude change.

James Pierson
NAR# 77907

Here's the latest incarnation of the Andromeda, incorporating the changes I mentioned in the earlier post. I'll try to get the outlines of the modified centering rings posted sometime tomorrow.

Attached Thumbnails

 

Attached Files

Andromeda Mk IV.rkt (80.6 KB, 433 views)

__________________
Craig McGraw

BARCLONE Rocketry -- http://barclone.rocketshoppe.com
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SAM 0044
AMA 352635

Here's the latest incarnation of the Andromeda, incorporating the changes I mentioned in the earlier post. I'll try to get the outlines of the modified centering rings posted sometime tomorrow.

Length: 23.95"
Diameter: 1.04" (BC-760) [Shrouds ST-16]
Fin Span: 5.799"
Weight: 1.9112 oz

CP = 14.8467" from nose tip

A8-3......138'......Dv 18 FPS......Requires 40" of guide length
B4-4......374'......Dv 3 FPS.......Requires 36" of guide length
B6-4......384'......Dv 4 FPS.......Requires 36" of guide length
C6-5......908'......Dv 16 FPS......Requires 36" of guide length

Enjoy!

__________________
Craig McGraw

BARCLONE Rocketry -- http://barclone.rocketshoppe.com
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SAM 0044
AMA 352635

Sorry for the almost-duplication. Computer-related glitch...

__________________
Craig McGraw

BARCLONE Rocketry -- http://barclone.rocketshoppe.com
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SAM 0044
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When I read this, the first thing that popped into my mind was
"There's a town I know where the hipsters go called BEDROCK, glitch, glitch."
Must be the anti-biotics....

__________________
Bill Eichelberger
NAR 79563

http://wallyum.blogspot.com/

I miss being SAM 0058

Build floor: Centuri Design Contest F-150 Hurricane Estes - Low Boom SST Semroc - Shrike, SST Shuttle

In paint: Estes Air Commander, B.O.S.S., F-22 Air Superiority Fighter, Long Tom, Solar Sailer II Semroc Cyber III, Excalibur, Firefly

Ready to fly: Estes - Pathfinder

Wowsy, wowsy, woo, woo...

"And I can't get it outta my head..."

__________________
Craig McGraw

BARCLONE Rocketry -- http://barclone.rocketshoppe.com
BARCLONE Blogsite -- http://barclone.wordpress.com
BARCLONE Forum -- BARCLONE Forum

BARs helping BARs

SAM 0044
AMA 352635

Kicking the "PhotoBucket" This is going to take me a while so please reamin calm and stay in your seats please, JP

Here are the mini Jets I have built as far #1- #5 I think.




And here is the Neptune Lander.




Here is the real version of the Static Probe with the three PNC's




Here is the Sabre Dart.




How about the Master Blaster as well.




A naked Cosmic Poo .



Here is my first serious attempt at scratch building. I call it he Old Ranger.



Hope you all enjoy these, JP

James Pierson
NAR#77907

James,

*Nicely* done on all of those models. I have to confess, sometimes I see the new stuff that you come up with, and I think, "Where does he *get* these ideas?!?"

Then I have to console myself with the thought, "At least my Tau Zero will have cool decals."


Cheers, buddy,

__________________
Jay Goemmer
"Centuri Guy"/"Tau Zero"
YORF Member 28
Semroc SAM #0029
NAR 86131


"I think about organizing things all the time. Never seems to happen. I find something that piques my interest and I'm off on a quest. Or a Centuri. "

--Bill Eichelberger, 02/22/2022


“Centuri fret buzz in an updated form.”
Bill “Wallyum” Eichelberger re: Estes Flutter-By
03 Sept 2014

Nice images, James. I need to match your gallery with some shots of my Barclone fleet. I've been wanting to get some "actual photos" of the models posted on the website for a long time, as opposed to just the RockSim rendered images.

It will help folks who are downloading the plans to see what the actual model looks like, and how large it really is.

__________________
Craig McGraw

BARCLONE Rocketry -- http://barclone.rocketshoppe.com
BARCLONE Blogsite -- http://barclone.wordpress.com
BARCLONE Forum -- BARCLONE Forum

BARs helping BARs

SAM 0044
AMA 352635