A lot of time when I would buy a kit or scratch build a rocket I would always make sure that the CG 1.5 ahead of the CP. Recently I purchased a couple kits from Madcow for instance the 4" Patriot.
It states in the instructions that the CG should be 28" from the nose tip. Now in Rocksim when you add mass to the nose cone you have a few selection. I selected "From the Nose Tip" which should match the specifications in the instruction by MADCOW. I know I'm answering my own questions here.
With 14oz of nose weight the puts the CG 29.9 from the tip of the nose cone and a margin of 1.60
Keep in mind I haven't added the nose weight yet. I guess my question is if I'm off a little is it going to make much of a difference or do most of you just go by the 1.5 rule, meaning the CG needs to be ahead of the CP by 1.5 x the airframes diameter in this case 5.5 inches.
I remember when I built the 2.2 Batray I added nose weight based on the 1.5 method or thereabouts and when I check where the CG was from the tip in Rocksim I was right on my calculations (17" from the tip and Madcow suggested 17.75 per instructions). Unfortunately this was after the first flight that corkscrewed without any nose weight. Since then I learned to always double check my numbers. Although with OR the numbers probably vary.
So I'm just looking for some feed back
It states in the instructions that the CG should be 28" from the nose tip. Now in Rocksim when you add mass to the nose cone you have a few selection. I selected "From the Nose Tip" which should match the specifications in the instruction by MADCOW. I know I'm answering my own questions here.
With 14oz of nose weight the puts the CG 29.9 from the tip of the nose cone and a margin of 1.60
Keep in mind I haven't added the nose weight yet. I guess my question is if I'm off a little is it going to make much of a difference or do most of you just go by the 1.5 rule, meaning the CG needs to be ahead of the CP by 1.5 x the airframes diameter in this case 5.5 inches.
I remember when I built the 2.2 Batray I added nose weight based on the 1.5 method or thereabouts and when I check where the CG was from the tip in Rocksim I was right on my calculations (17" from the tip and Madcow suggested 17.75 per instructions). Unfortunately this was after the first flight that corkscrewed without any nose weight. Since then I learned to always double check my numbers. Although with OR the numbers probably vary.
So I'm just looking for some feed back
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