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Falcon 9's stability

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Lukasino42

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If you look at the Falcon 9 rocket, it is basically a straight pipe with an enlarged nose. I've been told that the center of gravity of a rocket must be above the center of aerodynamic pressure, so how come the Falcon 9 (or really any other rocket that seems to be breaking this rule) is a stable rocket? The center of aerodynamic pressure must be quite high due to the shape of the rocket's nose, so what's going on here?
 

Lukasino42

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Oh... I may have underestimated the steering. Thanks for the answer.
 

heada

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Compare balancing a broom on your finger tip to a tight-rope walker. For the broom, you must constantly adjust your finger so that the broom is above it. For the tight-rope walker, they have a long balance bar that keeps the center of gravity below the "center of pressure" (not really, but simple example) The broom is like the Falcon-9 which uses active guidance by gimballed motors. The tight-rope walker is like our model rockets that must keep the CP and CG relationships in order to be stable.
 

OverTheTop

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Also, aerodynamically cylinders generally don't produce lift. The nosecone and transition will contribute to the lift, but the tubes not much at all, if I am remembering an aerodynamic text I read a while back.
 
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