Abstract: Snapshot data from a projectile traversing a resisting medium are analyzed o determine a lower critical value within the resisting medium where rapid yaw growth begins and a yaw-growth constant governing yaw growth from the lower critical value to an upper critical value. Snapshot data from additional projectiles are similarly analyzed. Curves produced by the solution of a differential equation, including the lower critical value and the yaw-growth constant, are overlaid graphically or analytically to provide an increased data density sufficient to improve substantially the ability to predict the yaw performance of the projectile.