Hypervelocity Railgun Experiments With Thunderbolt

Westinghouse Marine Systems developed and tested the Thunderbolt electromagnetic launcher from 1988 to 1992 as part of the Strategic Defense Initiative program. The Thunderbolt launcher used a capacitor-based 32-MJ pulsed power system to accelerate a 77-g projectile to 5.23 km/s with a kinetic energy of 1.05 MJ. Details of the design, components, and test program are provided here. The velocity was found to be limited by secondary arcs. However, the impact of the secondary arcs on the acceleration was mitigated by tailoring the armature current to maximize as the projectile reached the launcher muzzle.