An aerodynamic fairing whose floor has absolutely no contact with respect to the lateral panels over the entire length of the fairing along the longitudinal axis. A free space e is provided between the floor and the lower edge of each panel. There is a longitudinal mechanical gap between the floor and each of the lateral panels. The absence of any rigid mechanical connection between the floor and the lateral panels allows the transfer of the thermomechanical stresses from the floor to the lateral panels and therefore preventing the deformation of the fairing.