Behind Armor Effects of Extending Rod Technology

Extending rod penetrator technology has been an area of study within the armor/anti-armor community for at least the last 30 years. Most of the reported work, both experimental and computational, has been in the hyper-velocity impact regime (<2000 m/s) and has focused on penetration studies, primarily into steel, to find a method to increase the performance of long rod kinetic energy penetrators. From a system's perspective, launching a short rod and having it extend prior to impact is attractive if penetration can be increased with a lesser logistics burden. But penetration is not the only factor to consider. If the extending rod designed partitions penetrator cross-sectional area into nearly equal parts, the effective crater area at target break through will be less. This paper presents a study examining the effects extending rod penetrators may have on behind target debris at both ordnance and hyper-velocity impacts.