Grid Fin Reentry Steering (2D)

This 2D side-view companion isolates the rotational half of grid-fin reentry steering: a booster free to rotate about its own center of mass under torque produced by its grid fins. Dynamic pressure is computed the same way as the 3D version, from an exponential atmosphere and your altitude and airspeed sliders, but instead of only nudging cross-range position, the fin's lift force here acts at a real moment arm from the center of mass, generating a genuine torque that is integrated frame by frame into angular velocity and attitude — you can watch the vehicle visibly rotate in response to your deflection commands. A grid-fin lift-coefficient curve that stays effective out to roughly 50° angle of attack is compared, live, against a conventional planar fin that stalls near 14°, with both the torque-vs-deflection and lift-vs-angle-of-attack functions plotted as charts so the difference in control authority is not just described but shown.