Using light gas guns to launch sub-orbital payloads

Two-stage light gas guns are powerful accelerators, which are mainly used for terminal ballistics research, for example to simulate space debris and micrometeoroid hypervelocity impacts on spacecraft components. Light gas guns, similar to those operated by the Fraunhofer Ernst-Mach-Institute (EMI), are capable to accelerate projectiles with masses in the kilogram range to velocities of several kilometers per second. Such exit velocities achieved are sufficient to cover the delta-v demand of sub-orbital missions. Thus, an application of light gas guns for upper atmospheric research or hypersonic flight and re-entry experiments is feasible with state-of-the-art technology. This paper presents the concept of using light gas guns as a launch system for sub-orbital payloads. The peculiarities of light gas guns are described and the system performance, which also considers the option of a projectile integrated rocket motor, is put into perspective to competing gun-launch syst ems. Implications on the payload design, which are driven by high short-term acceleration loads, are discussed against the background of EMI's experiences with ballistic telemetry and compact sensor systems.