Planning on mod-ing to make the boosters flyaway.

All praise Excelsior Rocketry for great balsa and decal work!
(Sandman! Sandman! Sandman!)

This won't be a quick build, I'm afraid. Many irons in many fires.

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__________________
Charles McGonegal
Ciderwright
AEppelTreow Winery & Distillery
Ad Astra Tabernamque!

Just had to post so I get notices.

I'll be watching. We don't have a popcorn emoticon?

__________________
"I'm a sandman. I've never killed anyone. I terminate runners when their time is up." Logan from "Logan's Run"

http://sandmandecals.com/

Next steps.
Rack. Clean. Sanitize. Rack another. Distill.

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__________________
Charles McGonegal
Ciderwright
AEppelTreow Winery & Distillery
Ad Astra Tabernamque!

Since I'm a little concerned with convincing the local RSOs of the stability after modding to pop pod boosters, and I'm too thrifty to buy Rocksim, I'm taking some advice from both George and Jerry. (A sign of the end times, I'm sure).

So here's a downscale Titan IIIe built for 13mm core motor only. No booster gepoppen.

It looks a bit finny to me. After I fly it this way, I'll cut off the paired booster fins and try a single fin on each side.

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__________________
Charles McGonegal
Ciderwright
AEppelTreow Winery & Distillery
Ad Astra Tabernamque!

How does "FREE" sound?
http://openrocket.sourceforge.net/



.

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I love sanding.

Thanks tbzep.

You mean like this? (see pic)

Unfortunately, OpenRocket doesn't support pods.

I have the core and booster simmed separately.

I thought about taking a look on rocket reviews, to see if someone has posted a rocksim file - even the image usually displayed on the website would give me an idea of the Cp. But the original kit had (essentially) boost motor mount fitted fins - and I'm planning on clear fins and real motors on those mounts. So the Cp of the old kit doesn't quite apply anyway.

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__________________
Charles McGonegal
Ciderwright
AEppelTreow Winery & Distillery
Ad Astra Tabernamque!

I did a little more digging.

First, I tried a simming a worst case approximation of the Cp - I assumed the Cp of the stack would be the same as the rotated silhouette. So I added a transition at the height of the booster nose cones and took the thing out to the diameter of the combined core and boosters. Bleck. If that's a reasonable worst case, remind me not to fly this in a strong wind.

Next, I went looking for Rocksim files. Didn't find one - but DID find a post here by another CPMcG of a Delta IV Heavy. Core with boosters!

http://forums.rocketshoppe.com/showthread.php?t=5543

The Rocksim image puts the Cp way to aft - like modeling the core or boosters alone, rather than just behind the booster nose cones like the pseudo-cardboardcutout method did.

That makes me feel better.

__________________
Charles McGonegal
Ciderwright
AEppelTreow Winery & Distillery
Ad Astra Tabernamque!

If you are still worried about the first flight, you can temporarily add a long payload section to the core to make the rocket longer and move the CG forward. Once you see it in action, shorten it with your handy x-acto and fly it again. Once you're satisfied, replace the temporary payload section with the pretty finished scale length payload section. If you use a different nose cone, make sure it weighs about the same as the scale one.

__________________
I love sanding.

That sounds like a decent option. I wonder how much BT-70 I have laying about?

__________________
Charles McGonegal
Ciderwright
AEppelTreow Winery & Distillery
Ad Astra Tabernamque!

Test flight of the downscale with two pod fins went great.

http://www.youtube.com/watch?v=bhbWIxCBnN0
Beginning in slo-mo

This is on a single A10-3T

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__________________
Charles McGonegal
Ciderwright
AEppelTreow Winery & Distillery
Ad Astra Tabernamque!