A dart's remarkable self-correcting flight attitude, essential for accurate dartboard penetration, is attributed to its aerodynamic design, featuring a heavy barrel and large cruciform flights. We comprehensively characterize dart aerodynamics at low Reynolds numbers (14500-20500) through a multi-faceted approach. Wind tunnel experiments yielded lift, drag, and pitching moment coefficients, which were quantitatively corroborated by numerical simulations. Further numerical analysis, supported by smoke flow visualization, revealed that the dart's aerodynamics are governed by a complex interaction between the Barrel vortex (BV) shed from the body and the Wing Leading Edge Vortex (WLV) over the flights. This intricate interplay, which varies with the angle of attack, involves WLV elliptic instability and a partial merger with the BV, leading to the rapid weakening of the WLV. High-speed imaging of the dart's trajectory, coupled with a three-degree-of-freedom (3-DOF) mathematical framework, further elucidated its flight dynamics. Experimental observations confirmed that the flights are critical for successful penetration by generating aerodynamic moments that stabilize the dart's attitude and effectively suppress pitch oscillations. While translational motion is primarily governed by gravitational forces, these aerodynamic moments, though comparatively weaker, play a crucial role in maintaining flight stability. Ultimately, the dart's aerodynamics are primarily responsible for the aerodynamic force generation that induces pitch stabilization, leading to a proposed scaling law for dart flights that provides insight into the geometrical shapes of darts available in the market.
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