On the ballistic resistance of multi-layered targets with air gaps

High velocity penetration of a 3-D rigid sharp impactor into a ductile layered target with air gaps between the plates is studied using the assumption about the localized projectile--target interaction. The special property of the penetration phenomenon for conical-nosed impactors is established, namely, that the ballistic performance of the target is independent on the air gap widths and on the sequence of the plates in the target. Similar results arc also obtained for 3-D non-conical impactors on the basis of some class of models. These findings are in good agreement with available experimental results. © 1998 Elsevier Science Ltd. All rights reserved