Dynamic ram accelerator system

Abstract

Dynamic ram accelerator operation permits operation with lower acceleration, permitting launch of acceleration sensitive payloads such as crewed vehicles. Operational cost is reduced, and reliability improved, by reducing or eliminating internal consumable parts. Relative motion between a projectile and propellant at entry to the ram accelerator enables initial ram combustion at relatively lower velocity. Valves may maintain separation between sections within the ram accelerator that contain different propellant compositions. Timing of valve opening and closing is coordinated to provide conditions suitable for ram combustion. Control over propagation speed of propellant within the system may be obtained using one or more of baffle shape, baffle spacing, propellant temperature, propellant pressure, propellant mixture, temperature of components such as baffles, and so forth. Before the projectile is launched, internal separators between sections are removed, providing an open path to the ram accelerator exit.