Interlayer defects in structural components made of composite materials are caused by the imperfection of the manufacturing process, complex interactions of the constituents, and the effect of impact loads. The presence of these defects decreases the strength of such components and severely affects residual strength. The paper presents a numerical and experimental study of the behavior of a composite material plate with a variable layup angle under impact loading. Impactor velocities before and after multilayer plate perforation, as well as the dimensions of delamination-type defects, are determined experimentally. The Ansys LS-DYNA software in double precision mode is used to simulate the failure of composite plates under impact loading. It has been found that a significant contribution to the decrease in the impact energy is made by the delamination dimensions depending on the layup angle in the stack. The delamination area is related to the residual velocity of the impactor; namely, the larger the delamination area, the greater the decrease in the impactor velocity.