A STUDY ON MUZZLE VELOCITY ESTIMATION FOR NAVAL GUN PAC (PRE-ACTION CALIBRATIONS) FIRINGS USING NONLINEAR EQUATIONS OF MOTION

Pre-Action Calibrations (PAC) are critical for ensuring the accuracy and reliability of naval gun systems. PAC involves firing rounds at a safe bearing and range to analyze muzzle velocity (MV) and Mean Point of Impact (MPI) for correcting bias errors. Radar tracking identifies impact spots and measures projectile velocity at corresponding positions on an imaginary target. This data is used to estimate MV and adjust the Fire Control System (FCS) for improved precision. Factors such as propellant temperature, barrel wear, mass variation, and platform motion significantly affect MV, while meteorological conditions influence measured velocities. These non-linear factors make linearized methods inadequate for accurate MV estimation. To address this, a new method leveraging non-linear equations is proposed, enhancing MV estimation under non-standard conditions. This approach is particularly beneficial for systems like Gatling gun-based CIWS (Close-In Weapon System), where MVRS installation is not feasible, improving firing precision and operational readiness in challenging environments.