Operating experience with the 90 mm railgun at CEM-UT

A 90 mm×10 m-long railgun has been operated at the Center for Electromechanics at the University of Texas at Austin (CEM-UT) with great success, and several improvements were recently added. The testing has involved various types of projectile packages, including split armature designs for midbody drive projectiles as well as base-push packages. An 8.1 MJ experiment was performed, as well as many lower energy tests, as part of an ongoing armature/projectile development program. One of the most important features added to the system was the development of thermal opening switches for smoother commutation into the gun and reduced acceleration loads on delicate projectile packages. Other new features include a copper-vapor laser for enhanced high-speed film data and a target X-ray system for capturing projectile data just before and after impacting the target. Both the copper-vapor laser and the target rays add to the excellent data collection and shot evaluation system