Optimization of a compact two-stage light-gas gun aiming at a velocity of 9 km/s

We developed a compact two-stage light-gas gun and optimized several operat ing parameters for aiming at velocities higher than 9 km/s. A firing test a chieved a velocity of 6.2 km/s using helium as driver gas with a projectile weighing 0.6 g and a piston weighing 430 g. In the case of firing tests us ing hydrogen, a velocity of 8.1 km/s was obtained under the same condition. Moreover, it was found that higher velocities could be achieved by using a lighter piston to increase piston velocities, and that the efficiency of a cceleration strongly depended on the initial gas pressure for each piston. Finally, a projectile velocity of 8.9 km/s was achieved using a piston weig hing 290 g. (C) 2001 American Institute of Physics.