This study investigates the impact of drag coefficient intermittency near the drag crisis on the vertical motion of a smooth sphere falling freely through quiescent air. Using a stochastic two-state model for the drag coefficient, we show that the temporal evolution of the sphere's velocity becomes intrinsically unpredictable, requiring a statistical description of the coupled friction and gravity forces. Numerical simulations as well as a stochastic model reveal broad distributions, with relative dispersions reaching up to 50% of the mean velocity under certain conditions. These findings suggest that drag crisis intermittency can significantly affect the predictability of falling-body trajectories, with implications for both fundamental fluid dynamics and applied contexts such as ballistics or sports aerodynamics.

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• Aerodynamics
• Fluid-particle interactions