This paper deals with the comparison of experimental measurements and numerical simulation of the natural frequency and natural shape of a carbon fibre monocoque. This comparison is used to validate the numerical analysis with a real monocoque. Usually, monocoques consist of orthotropic materials like carbon fibre sandwich with a honeycomb core. The monocoque is manufactured by hand from several layers of different materials, which are connected by glued joints. This does not guarantee the material properties or the same mass the idealized numerical simulation.