Demonstration of a hypervelocity mass-efficient integrated launch package

Tests were conducted whereby a kinetic energy penetrator was launched from an electromagnetic launcher. The penetrator was fabricated from a tungsten alloy. An armature, which supported the penetrator during acceleration and conducted the rail current, was fabricated from 7075-T6 aluminum. The transition of the armature contacts from a low voltage to a high voltage was identified as the mechanism that caused the aft section of the subprojectile to fail. Transition occurred fairly consistently at an average velocity of 2050 m/s. Removal of armature material at the rod-armature interface increased the survivability of the subprojectile and was demonstrated with a launch package mass of 308.5 gm, yielding a useful mass fraction of 49%. Structural integrity of the subprojectile at a launch velocity of 2350 m/s was verified with an orthogonal flash X-ray image at the muzzle.