AbstractA study of the influence of the reinforced fiber orientation and the propellant aluminum content on the ablation and erosion performance of Ethylene Propylene Diene Monomer type insulation is presented. A subscale solid rocket motor has been used, with ammonium perchlorate and hydroxyl‐terminated polybutadiene propellant composition. Seven static firing tests were conducted: six with low Al and one with high Al content. The EPDM articles had four different Kevlar fiber orientations: circumferential, longitudinal, diagonal (45°), and random. Numerical simulations were supplemented to decipher the experimental outcome. The numerical results exhibit an over‐prediction tendency, yet they show that the examination of post‐fire charring of the insulation is insignificant. The test results indicate that the longitudinal fiber orientation has the least ablative resistance.