To ensure the structural integrity of airplanes in flight conditions, aeronautical composite structures need to be able to withstand extreme load such as lightning strikes [1]. These intense loadings cause delamination in the core of the laminate. As soon as they appear, from the beginning of the charge deposition, delamination act as an obstacle for the propagation of the shock and rarefaction waves produced by the strike. The induced modification of the load path is detectable in experiments via the recording of the velocity at the rear face. The numerical simulation is used to better understand the influence of the anisotropic layering on the wave propagation up to the rear face. Most of the existing work focuses on the challenges of the composite plies’ damage modelling and represent interlaminar interfaces using cohesive elements or constraints in numerical models. Recent work [2] has shown that the behaviour and fracture of thick interlaminar adhesive joints play an important role in the velocity of the rear side. This paper presents the methodology and results of research aimed at modelling sudden or progressive damage in interlaminar interfaces and its induced effects on the wave propagation and rear velocity. Starting from a classical 2D representation of a single interlaminar interface on the finite element software LS-Dyna [3], the analysis aims to evaluate the interest of 3D representation of the interface to ensure the reproduction of the rear face velocity. The numerical results are compared to laser shock experiments and relevant results from the literature [4]. It is shown that a modelling of the thickness of the interfaces is necessary to explain some events in the rear face velocity signal.