Ballistic protection plates for military helicopters structures: Experimental and numerical research

• Published in: Materials today : proceedings 2023, Vol.93, p.618-624
• Main Authors: Adetu, Catalin, Hadar, Anton, Nastasescu, Vasile, Adetu, Alina Elena, Voicu, Andrei Daniel, Pastrama, Stefan-Dan
• Format: Article
• Language: English
• Subjects: Ballistic protection systems; Finite element analysis; Honeycomb core; Kinetic energy; Sandwich plate
• ISSN: 2214-7853; 2214-7853
• DOI: 10.1016/j.matpr.2023.03.774

•The ballistic capabilities of three different types of protection plates having aluminum and/or steel skins and aluminum honeycomb core were studied.•For each plate, the velocity before and after penetration was measured following shootings with two types of bullets from a distance of 10 m.•Numerical models obtained using the finite element model were validated by comparison between numerical and experimental results, where a and a very good accuracy was noticed with differences less than 5%.•Conclusions were drawn regarding the ballistic efficiency of each of the three considered sandwich plates.•The validation of the numerical models opens the path for the future assessment of other types of protection systems, made of lighter materials for the skins of the sandwich plates, namely fiber reinforced composites. The paper presents a combined experimental - numerical research that tries to evaluate the ballistic capabilities of three different types of protection plates having aluminum and/or steel skins and aluminum honeycomb core. Shootings with two types of bullets from a distance of 10 m were performed for each plate in an approved military training ground, which ensured the necessary safety and performance conditions. For each plate, the velocity before and after penetration was measured using an ultrafast camera, and a freeware code. The diameter of the hole made by the bullets was also measured. The experimental results were compared with the numerical ones obtained using the finite element method and a very good accuracy was noticed with differences less than 5%, validating thus the numerical models. The assessment of the degree of protection for each plate was made by evaluation of the energy absorbed by the plate from the kinetic energy of the bullet and by the reduction of the bullet velocity after penetration. The mass of each protection plate was also analyzed since it is a critical factor in the design of the ballistic protection systems. Conclusions were drawn regarding the efficiency of each of the three considered sandwich plates. The validation of the numerical models opens the path for the future assessment of other types of protection systems, made of lighter materials for the skins of the sandwich plates, namely fiber reinforced composites.