Technology of thermal hypervelocity launchers

A new type of hypervelocity launcher is described, the Thermal Hypervelocity Launcher (THL). The THL uses stored thermal energy in a compact, lightweight particle bed heater to rapidly (milliseconds) heat a high pressure low molecular weight propellant (hydrogen or helium). The hot propellant then expands in a conventional barrel accelerating the projectile. The THL can achieve velocities up to -12 km/sec. The technology of the THL is described, including experiments on thermal-hydraulics of particle bed heaters. An experiment that will demonstrate THL operation with 100 gram projectiles at 3 km/sec is being attempted.