NRL materials testing facility

The Naval Research Laboratory performs basic research on high power railgun electric launchers. The program uses a 1.5-MJ, 2.5 km/s launch velocity railgun located in NRL's Materials Testing Facility. The railgun consists of an 11-MJ capacitive energy store configured as 22, 0.5-MJ modules. Each bank module has an independently triggered thyristor switch, series inductor, and crowbar diode and is joined to the railgun breech with coaxial cables. Individual bank timing and charge levels can be set to produce up to 1.5 MA peak current and 4-5 ms long current pulses. The 6-m long railgun used a nominally 5 cm bore diameter with steel or copper rails and epoxy laminate insulators. The muzzle contains a Tungsten-Copper arc horn to minimize damage from residual drive current upon launch. Aluminum armatures with acrylic bore riders are used for the launch package. Launch data is recorded digitally and analyzed using in-house computer codes. The system design and operation will be discussed.