Thunderbolt [railguns]

The Thunderbolt program facility will provide 60 MJ of energy at 21 kV from capacitor banks for powering breech-fed or distributed energy railgun electromagnetic launchers. After discharge from the capacitor banks, the energy pulse is shaped with room-temperature solenoidal inductors, with switching being provided by D and E-sized ignitrons. Fast recharging of the capacitor banks could permit repetitive operation. A screened room provides protection for the control and data acquisition equipment, while a single-point ground scheme protects against ground loops. A substantial foundation provides support for the catch tank, while high-vacuum equipment will permit operation at high velocities with the round-bore railgun. Preinjection of the test projectiles to velocities of about 1 km/s is provided by a helium gas gun to minimize damage to the breech section of the railgun. In addition to providing details on Thunderbolt, operating experience and results obtained with a subscale launcher are described