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Sorry folks - another thread asking questions on a mach breaking min diameter rocket...
I recall seeing various threads (although I couldn't locate any right now) that A rocket that is going to break mach needs a higher level of stability because the CP will move forward
I've modeled my rocket in Rocksim, OR, and RasAero (although the RasAero was a rougher model with some numbers from memory - it needs to be cleaned up)
I grabbed a plot from OR. It shows the CP moves back, then it moves forward again to its original position, then back again, then slowly forward again.
Meanwhile, the CG moves forward as the motor burns.
Note - I also looked at a similar plot from RasAero which showed similar changes
So am I missing something? I can get more performance if I tighten up the CP/CG closer to 1 caliber
I recall seeing various threads (although I couldn't locate any right now) that A rocket that is going to break mach needs a higher level of stability because the CP will move forward
I've modeled my rocket in Rocksim, OR, and RasAero (although the RasAero was a rougher model with some numbers from memory - it needs to be cleaned up)
I grabbed a plot from OR. It shows the CP moves back, then it moves forward again to its original position, then back again, then slowly forward again.
Meanwhile, the CG moves forward as the motor burns.
Note - I also looked at a similar plot from RasAero which showed similar changes
So am I missing something? I can get more performance if I tighten up the CP/CG closer to 1 caliber