Abstract: The warship continues to move after the trajectory correction projectile is fired from shipborne gun, and the shipborne radar for trajectory measurement also continue to move and sway, and so the rela- tive trajectory measured by radar need to be transformed into the ballistic reference frame which takes the gun muzzle as an origin during firing. The precision of transformed ballistic coordinates is influenced by the warship fluctuation and the errors of radar measuring, warship sway angles, velocity and course bear- ing. In order to quantify the influence of every error on the precision of ballistic coordinates, a model of precision of ballistic coordinates was set up and simulated, and some data about the influence of warship fluctuation and the errors of radar measuring, warship sway angles, velocity and course bearing on the precision of ballistic coordinates were got.

Key words: ordnance science and technology, trajectory correction, coordinate transformation, precision