Electromagnetic Launching for Affordable Agile Access to Space

The conceptual design of a novel, hypersonic electromagnetic launch system has been developed. Phase-1 assumed a 100-kg projectile leaving the launcher at 7,000 m/sec. The projectile is propelled and levitated by electromagnetic forces inside a tube filled with low pressure helium. A controlled acceleration profile, fully adjustable to the requirements of various missions, is used to reach 5000 gees in a 500-meter long launch tube. A constant-flux synchronous motor concept, developed during Phase-1, is a breakthrough technology that provides contact-free propulsion and self-centering suspension with sufficient stiffness and thrust. Rapid spin introduced into the projectile prior to acceleration enhances trajectory stabilization. The use of high-current, persistent-mode superconducting coils in the projectile generates high thrust force with near-zero heat dissipation. No brushes or projectile power supplies are needed. The low-pressure helium atmosphere in the launcher reduces aerodynamic disturbances and aerothermal heating during acceleration. The system is highly scalable to various payloads and launch speeds for a wide range of applications from kinetic kill weapons to direct LEO insertion of small payloads. The enabling technologies of the system, the constant-flux synchronous motor and the high-current superconducting projectile coils, will be qualified in the proposed Phase 2.