First experimental results with the ISL 10 MJ DES railgun PEGASUS

A 10 MJ DES railgun with 12 current inputs distributed along the 50-mm roun d bore launcher has been built at ISL, The power supply consists of 200 LCR Pulse Forming Units of 50 kJ each, The 6-m-long launcher tube containing t he Cu-Cr rails is made of both wound glass fiber and wound carbon fiber rei nforced plastic. This paper presents the facility and the first experimental results obtaine d by using projectiles made of Ti or equipped with metallic fiber-brush arm atures. The triggering of the 12 DES stages is synchronized with the positi on of the projectile detected by B-dot probes located along the launcher tu be. The currents delivered by the stages are measured by means of Rogowski coils surrounding the injection slots, The maximum total current reaches 2 RIA resulting from the addition of the 12 current profiles of 800 kA delive red by each stage of the DFS energy supply, The launcher has proved to have an overall efficiency of about 30%. Projectiles with masses ranging from 3 00 g to 650 g have been accelerated up to velocities of 2300 m/s, The quali ty of the electrical contact between rails and armature has been analyzed b y electrical measurements and flash radiographs.