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Walldiver7

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This afternoon while playing around with various sims, I noticed something weird about OR. In my sims, when I set an overriding mass for the NC the stability cal figure of the rocket changes when I vary the thickness of the NC, or the shoulder of the NC. The CG is moving on my sim when I enter different values for thickness, but the overall mass of the rocket doesn't change.

So, what am I missing here?
 
Uncheck override mass. If the mass is overridden on an object and you then change the properties of said object, the overall vehicle mass isn't changing because the mass of the object isn't changing due to the override.
 
Walldiver7 said:
This afternoon while playing around with various sims, I noticed something weird about OR. In my sims, when I set an overriding mass for the NC the stability cal figure of the rocket changes when I vary the thickness of the NC, or the shoulder of the NC. The CG is moving on my sim when I enter different values for thickness, but the overall mass of the rocket doesn't change.

So, what am I missing here?
Click to expand...

Even though the mass of the NC is staying constant, its center of mass changes depending on where that mass is distributed on the NC - i.e the shoulder or the NC itself. If the NC's C.O.M. is moved forward by these changes (thicker NC wall, so more volume, with constant density more weight here vs. thinner shoulder) , the overall stability will increase. If its moved back, the stability decreases.
 
You should override the CG of the component if you are going to be changing thickness in one area of the component. This behavior sounds logical to me. OR is recalculating where the weight is concentrated(nose cone shoulder for example).

Manually figure where the nose cone CG is and enter that as the CG overridden value, along with the new override weight.
 

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