US Patent 7526988 Electromagnetic railgun projectile

An electromagnetic railgun projectile is disclosed which includes an aeroshell having a substantially flat surface extending along the length thereof. The substantially flat surface is configured to increase the lift-to-drag ratio of the projectile during reentry. The projectile also includes an armature integrated into the aeroshell substantially near the center-of-gravity of the projectile, and a plurality of extendable flaps attached to the aeroshell. The flaps are capable of stabilizing the projectile during an unguided portion of its flight and maneuvering the projectile during a guided portion of its flight.