Body armors must protect the human body from the ballistic penetration of small arms projectiles and to reduce the blunt trauma or the back face signature caused. Blunt trauma can cause severe injuries to vital organs of the body such as heart, liver, lungs kidneys, etc. The design of ballistic-resistant armor requires identification of the threat, selecting a
material or combination of materials that resist such a threat, and determining the number of layers of material necessary to prevent both penetration and blunt trauma injury. The final weights of such armors represent an important factor when selecting the materials used for constructing them. Therefore, the main goal is concerned with the design of lightest possible unit that achieves the desired protection and provides comfort and not restricting movement. In this paper, the ballistic resistances as well as Back Face Signature (BFS) of two ballistic panels have been examined, one was normal panel, and the other was treated by applying thin layer of a flexible polymeric material on its back face. An experimental program has been conducted to study the normal penetration of a 9×19 mm projectile into each of the two body
armor panels. The program is concerned with the determination of the back face signature depth and its maximum diameter. Autodyn-3D hydro-code was used for simulating the projectile penetration process into the prepared ballistic panels [1]. The input data of projectile and body armors used in experimental program were fed into the code. The numerical simulation results were compared with the corresponding experimental measurements.