COMPOSITE ROCKETRY ROCKSIM FILES

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Justin you have some mad skills with those bevels on 1/8" G10 fins.

I had mine cropped a little more and a shout out to Composite Warehouse for not charging any extra.
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I'm building the Lotus 3 and 5 right now.

But I'll definitely take you up on that offer for the Lotus 8 fins.
 
Neither, I'm using open Rocket. Looks much better and now I see the problem you're pointing out with a long motor case.

Since you're light years ahead of me with rocksim, do you think cropping the fins would have any stability issues?
When I design fins or modify an original fin design, I just iterate until I get the stability I need for the biggest engine I'll use. First get the basic fin shape you want. If the stability is too low, increase the root chord and semi-span dimensions proportionally until you get the stability required. If too high, do the reverse. When you get it to where you want it, then adjust the TTW fin tab parameters to fit your MMT. The fin tabs slightly shift the CG back, so a final iteration may be required.

Rocksim and Openrocket make it easy and fast to iterate. I do the iteration with the engine loaded, so I get an updated stability value as soon as you make the fin size adjustments.
 
I designed the LOTUS Series for Composite Warehouse, Here are the real Rocksim files. Just change the weight and the CG to what your kit comes out to. Also I use a ratio between Rocksim and the Barroman method to determine my CP. Here is what I recommend for the CP for each size LOTUS.

3" CP - 25.65 from the NC Tip
5" CP - 39.94 from the NC Tip
8" CP - 62.40 from the NC Tip
Gary,

Do you have the RockSim file for the Lotus 4SE

Thanks

Deb
 
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