Electromagnetic gun/projectile interface considerations

Projectile/electromagnetic-gun interface design considerations for electromagnetic gun weapon system (EMGWS) area D1 projectiles, area B-guns, and area C-guns are presented. Projectile/EM gun interfaces are primary considerations in the projectile structural design and the design of the sabot obturator/bore rider, pusher plate, and armature. Acceleration profile, armature type and mass, preinjector characteristics, bore pressure, magnetic fields, and plasma temperature are all key issues in the ultimate projectile performance. Armature design is a critical technical issue for both the projectile and EM gun design because of the high masses involved. Solid armatures are heavier than plasma armatures, but operate at higher electrical efficiencies. Plasma armatures are both being considered for the B-guns and C-guns. Performance tradeoffs are presented for penetration versus peak acceleration and armature mass. Contributors to projectile dispersion such as in-bore balloting, projectile spin, and EM launcher muzzle arc effects are assessed