Bird impact studies on glass fiber–pmi foam sandwich panel with different skin and core thickness combinations

To endure the bird strike damage on airborne radomes, the radome material must possess both bird-impact resistance and electromagnetic transparency. Glass fiber reinforced polymer (GFRP) with polymethacrylimide (PMI) foam core provides an optimal equilibrium of these characteristics. This study seeks to ascertain the critical bird impact velocity that causes the bird to penetrate the radome structure, which safeguards the antenna and electronics it houses. Experimental and numerical simulation studies indicated that an A-type GFRP-PMI foam composite sandwich panel of 1[Formula: see text]sq. m with a thickness of 39[Formula: see text]mm under an edge-fixed boundary condition can withstand the impact of a 4-pound bird with velocities up to 143[Formula: see text]m/s without penetration. The numerical simulation is extended to examine the panels with varying core and skin thickness. The simulation results show that a composite sandwich panel with a skin thickness of 1[Formula: see text]mm and a core thickness of 9[Formula: see text]mm may withstand a bird impact velocity of up to 87[Formula: see text]m/s, and this resistance can be enhanced to 156[Formula: see text]m/s by raising the skin thickness to 2[Formula: see text]mm and the core thickness to 36[Formula: see text]mm. Augmenting the core’s thickness is more effective in enhancing avian impact resistance and achieving electromagnetic transparency than augmenting the skin’s thickness. The graph depicting threshold bird impact velocity versus core thickness for different skin thicknesses can be utilized for the preliminary design of a composite radome’s skin-core thickness capable of withstanding a certain bird impact velocity.