The ongoing trend towards improved aircraft efficiency in-volves the usage of higher-strength materials. In this context, carbon fiber reinforced polymers (CFRP), and more generally composite assemblies, have increasingly been used for the fuselage and nacelle’s fairing. They have gradually replaced heavier metallic alloys, thus improving the overall performance. Yet, a critical part of the design phase remains the fire certification of all components. Current international standards, such as the FAR25.856(b):2003 and ISO2685:1998(e), ensure the thermal resistance of these lighter materials when submitted to high-heat loads. Still, certification test campaigns are costly and often require a long time for their set-up. The introduction of numerical tools for the prediction of the degraded material properties could provide supplementary inputs and thus improve the design process. For the past decades, Large-Eddy Simulation (LES) has become a valuable tool for the simulation of unsteady reactive flows [1, 5, 11]. Several Conjugate Heat-Transfer (CHT) approaches have been performed to address the unsteady interactions between a fluid and a solid solver [5, 6]. These efforts have allowed to estimate the impact of the flame on the temperature distribution of solid geometries. However, the number of studies addressing the interaction of a flame leading to a composite plate degradation is limited [4]. In the present paper, a methodology for the coupling between a fluid, radiation and a solid solver, capable of respectively solving for the reactive, radiative heat losses and the thermal degradation of composite material, is presented. The procedure is first validated under simplified test-bed conditions on a so-called BLADE test [7]. In this context, a high-intensity laser beam replaces the external heat source from a flame.