Superconducting projectile for a rail gun and the combination of a rail gun with a superconducting projectile

A projectile for launching from a rail gun including first and second parallel, elongated electrically conducting metal rails insulated from each other and connected to opposite terminals of a DC power supply, the projectile comprising a forward portion, a rear portion, and an armature between the forward and rear portions, the rails and projectile armature being arranged so that current flows from one terminal of the power supply longitudinally of one of the rails thence through the projectile to the other rail thence longitudinally of the other rail back to the other terminal of the supply, the armature including multiple spaced mutually insulated longitudinally extending regions of superconducting material arranged so that current flowing longitudinally in the rails from the power supply flows between the rails longitudinally through the multiple spaced regions of the superconductors material with a component at right angles to the elongated direction of the rails, the multiple spaced regions of the superconducting material being arranged, positioned and of a type that the current flowing longitudinally through them produces a force for driving the projectile longitudinally along the rails, a metal region between each of multiple pairs of adjacent spaced regions of superconducting material for coupling current between the rails to the superconducting material regions while the superconducting material in the vicinity of the rails is normal, and a dielectric region extending in the same direction as the regions of superconducting material between each of multiple pairs of adjacent spaced regions of superconducting material for causing said current to be distributed amongst the multiple spaced superconducting material regions.

In combination, first and second parallel, elongated electrically conducting metal rails insulated from each other and connected to opposite terminals of a DC power supply, a projectile initially located at a position so it can traverse a gap between the rails and be accelerated longitudinally of the rails, the projectile including an armature, the rails and projectile armature being arranged so that current flows from one terminal of the power supply longitudinally of one of the rails thence through the projectile to the other rail thence longitudinally of the other rail back to the other terminal of the supply, the armature having multiple longitudinally extending mutually insulated superconductors arranged so that current flowing longitudinally in the rails from the power supply flows between the rails longitudinally through the superconductors with a component at right angles to the elongated direction of the rails, the superconductors being positioned, arranged and of a type that the current flowing longitudinally through them produces a force for driving the projectile longitudinally along the rails, the superconductors having a tendency to go normal in the vicinity of the rails in response to heating of the superconductors in the vicinity of the rails while the projectile is travelling along the rails, and means on the projectile for shunting current from the power supply around the portion of the superconductors having a tendency to go normal to the remainder of the superconductors in the superconducting state.

In combination, first and second parallel, elongated electrically conducting metal rails insulated from each other and connected to opposite terminals of a DC power supply, a projectile initially located at a position so it can traverse a gap between the rails and be accelerated longitudinally of the rails, the projectile including an armature, the rails and projectile armature being arranged so that current flows from one terminal of the power supply longitudinally of one of the rails thence through the projectile to the other rail thence longitudinally of the other rail back to the other terminal of the supply, the armature having multiple mutually insulated longitudinally extending superconductors arranged so that current flowing longitudinally in the rails from the power supply flows between the rails longitudinally through the superconductors with a component at right angles to the elongated direction of the rails, the superconductors being arranged, positioned and of a type such that said current flows longitudinally through the superconductors at right angles to and between the rails to produce a force for driving the projectile longitudinally along the rails, the armature having a length between the rails that is slightly less than the distance between the rails, the projectile including means for maintaining a gap between the armature and the rails where the armature length is slightly less than the distance between the rails, the gap being such that frictional heating of gas between the rails and the armature causes a plasma to be established in the gap, the plasma coupling current from the rails to the armature.