This property scales a mesh along each axis by the scale values given, e.g. 2.5/2.5/2.5 makes the object 2.5 times larger along each axis. Normally you should simply set objects to their proper scale when modelled. Scale is used in the Wasserfall rocket to fool the physics engine.
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This property defines the visual X/Y/Z scale of a geometry object. It does not alter the physics or collision box size of the object.